Laminate for cover window

Abstract

Provided is a laminate for a cover window, comprising: a hard coating layer including a cured product of a composition for forming a hard coating layer comprising polysilsesquioxane, an aliphatic urethane (meth)acrylate oligomer, and a heterocyclic compound containing oxygen; and an acrylic coating layer including a cured product of a composition for forming an acrylic coating layer comprising a silane coupling agent in the form of an oligomer, wherein the weight ratio of the aliphatic urethane (meth)acrylate oligomer and the heterocyclic compound containing oxygen in the composition for forming a hard coating layer is 1:1.5 to 7.

Description

Laminate for cover window The present invention relates to a laminate for a cover window. Tempered glass and plastic are used as cover materials to protect the display panel screen. Recently, flexible display panels that can be flexibly bent or curved have attracted significant industry attention. Following this trend, ultra-thin tempered glass (UTG) or colorless polyimide (CPI) films with flexible properties are being used as cover window materials. However, these materials are weaker than conventional glass, making them prone to breakage and physical deformation. To overcome these shortcomings, efforts are being made to add another film material as a protective layer on the top and bottom surfaces or to apply coating materials to maintain flexibility while improving strength. An object of the present invention is to provide a laminate for a cover window having excellent hardness, surface properties, bending properties, and viscoelastic properties. An object of the present invention is to provide a laminate for a cover window including a hard coating layer and an acrylic coating layer, and having excellent hardness, surface properties, bending properties, and viscoelastic properties. An object of the present invention is to provide a composition for forming a hard coating layer for manufacturing a hard coating layer of a laminate for the cover window. The purpose of the present invention is to provide a composition for forming an acrylic coating layer for manufacturing an acrylic coating layer of a laminate for the cover window. The objectives of the present invention are not limited to those mentioned above. Other objectives and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the objectives and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims. In one embodiment of the present invention, A hard coating layer comprising a cured product of a composition for forming a hard coating layer, the composition comprising polysilsesquioxane; an aliphatic urethane (meth)acrylate oligomer; and a heterocyclic compound containing oxygen; and An acrylic coating layer comprising a cured product of a composition for forming an acrylic coating layer comprising a silane coupling agent in the form of an oligomer; In the composition for forming the hard coating layer, the weight ratio of the aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound is 1:1.5 to 7. Provides a laminate for a cover window. The above polysilsesquioxane may include a structural unit represented by chemical formula 1-1 and a structural unit represented by chemical formula 1-2. <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms. The above polysilsesquioxane may contain 0.1 to 10 wt% of an alkoxy group represented by -OR2 in the above chemical formula 1-2. The above polysilsesquioxane can be represented by chemical formula 1. <Chemical Formula 1> In the above chemical formula 1, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms, n and m are each independently an integer between 1 and 100,000, and, however, n and m only mean the number contained in one molecule of polysilsesquioxane represented by the above chemical formula 1, and the structural unit of the above chemical formula 1-1, which exists in n numbers, and the structural unit of the above chemical formula 1-2, which exists in m numbers, are not limited in their connection order and can be connected in a random order. The composition for forming the hard coating layer may include (a) 100 parts by weight of polysilsesquioxane; (b) 7 to 350 parts by weight of an aliphatic urethane (meth)acrylate oligomer; (c) 25 to 750 parts by weight of a heterocyclic compound containing oxygen; (d) 0.1 to 5 parts by weight of a cationic photopolymerization initiator and a radical initiator; and (e) the remainder of an additive. The composition for forming the above hard coating layer may be solvent-free. The above aliphatic urethane (meth)acrylate oligomer can be represented by the following chemical formula 3. <Chemical Formula 3> In the above chemical formula 3, A is a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent aromatic hydrocarbon group having 5 to 60 carbon atoms, or a divalent siloxane group, B is hydrogen or a methyl group, n and m are integers from 1 to 20. In the above chemical formula 3, A may be a group represented by at least one of the following chemical formula 3-1, the following chemical formula 3-2, and the following chemical formula 3-3. <Chemical Formula 3-1> <Chemical Formula 3-2> <Chemical Formula 3-3> In the above chemical formulas 3-1 to 3-3, R1 and R2 are each independently an alkyl group having 1 to 12 carbon atoms, n is an integer from 1 to 30, and * represents a connecting portion. The compound represented by the above chemical formula 3 may be a compound represented by the following chemical formula 31 or the following chemical formula 32. <Chemical Formula 31> <Chemical Formula 32> In the above chemical formulas 31 and 32, B is hydrogen or a methyl group, PDMS is represented by the following structural formula: n is an integer from 1 to 30, and * indicates a connection point. The heterocyclic compound containing the oxygen may be a compound having an oxetane ring having a hydroxyl group. The composition for forming the above acrylic coating layer is: (a) 100 parts by weight of a monofunctional component including a monofunctional (meth)acrylate monomer or oligomer; (b) 50 to 250 parts by weight of a polyfunctional (meth)acrylate monomer or oligomer; (c) 10 to 50 parts by weight of a polyfunctional thiol compound; (d) 0.1 to 50 parts by weight of one or more photopolymerization initiators; and (e) 0.1 to 50 parts by weight of a silane coupling agent. The above silane coupling agent may be in the form of an oligomer containing 2 to 20 structural units represented by the following chemical formula 2. <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5. The weight average molecular weight of the above silane coupling agent may be 1,000 to 2,000. In the above chemical formula 2, -OR3 can be selected from the group consisting of a hydroxyl group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a pentyloxy group, a hexyloxy group, and combinations thereof. The above silane coupling agent can be represented by the following chemical formula 21. <Chemical Formula 21> In the above chemical formula 21, R3 is an alkyl group having 1 to 20 carbon atoms, L3 is an alkylene group having 1 to 10 carbon atoms, m2 and n2 are each independently an integer from 1 to 10, and provided that n2 and m2 only mean the number contained in one molecule of the compound represented by the chemical formula 21, and the connection order of the n2 structural units and the m2 structural units is not limited and can be connected in a random order. The modulus of the above acrylic coating layer may be 10 MPa to 5000 MPa. The hardness of the above hard coating layer may be 3H or higher. The thickness of the acrylic coating layer may be 10 µm to 600 µm, and the thickness of the hard coating layer may be 10 µm to 200 µm. The thickness ratio of the acrylic coating layer and the hard coating layer may be 20:1 to 1:4. In one embodiment of the present invention, Polysilsesquioxane; aliphatic urethane (meth)acrylate oligomer; and a heterocyclic compound containing oxygen; The weight ratio of the above aliphatic urethane (meth)acrylate oligomer and the above oxygen-containing heterocyclic compound and the above aliphatic urethane (meth)acrylate oligomer is 1:1.5 to 7. A composition for forming a hard coating layer for a cover window is provided. The above polysilsesquioxane may include a structural unit represented by chemical formula 1-1 and a structural unit represented by chemical formula 1-2. <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms. In one embodiment of the present invention, a composition for forming an acrylic coating layer for a cover window is provided, which comprises a silane coupling agent in the form of an oligomer represented by the following chemical formula 2. <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5. The laminate for the cover window of the present invention has excellent hardness, surface properties, bending properties, and viscoelastic properties. In addition to the effects described above, specific effects of the present invention are described below while explaining specific details for carrying out the invention. Figure 1 schematically shows a cross-section of a laminate for a cover window according to one embodiment of the present invention. Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and are not intended to limit the present invention. The present invention is defined solely by the scope of the claims set forth below. In this specification, unless otherwise defined, the term “substituted” includes a case where the term is substituted with a substituent selected from the group consisting of hydrogen, deuterium, a halogen atom, a C1~C30 alkyl group, a C3~C50 cycloalkyl group, a C2~C30 alkenyl group, a C3~C50 cycloalkenyl group, a C2~C30 alkynyl group, a C5~C50 cycloalkynyl group, a cyano group, a silyl group, a C1~C20 alkoxy group, a C5~C60 aryl group, a C1~C60 heteroaryl group, and a C6~C60 arylalkyl group, and combinations thereof. In one embodiment of the present invention, A hard coating layer comprising a cured product of a composition for forming a hard coating layer, the composition comprising polysilsesquioxane; an aliphatic urethane (meth)acrylate oligomer; and a heterocyclic compound containing oxygen; and An acrylic coating layer comprising a cured product of a composition for forming an acrylic coating layer comprising a silane coupling agent in the form of an oligomer; In the composition for forming the hard coating layer, the weight ratio of the aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound is 1:1.5 to 7. Provides a laminate for a cover window. In one embodiment, the polysilsesquioxane may include a structural unit represented by Chemical Formula 1-1 and a structural unit represented by Chemical Formula 1-2. <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms. The laminate for the above cover window includes an acrylic coating layer that implements the bending control properties and viscoelastic properties of the coating film by the acrylic coating layer, and a hard coating layer for implementing hardness and surface properties. The laminate for the cover window can be used as a cover material, such as a cover window that protects the screen of a display panel. In one embodiment, the laminate for the cover window can be applied as a cover window of a flexible display panel. The laminate for the cover window can replace existing glass, UTG, or CPI film. Fig. 1 schematically illustrates a cross-section of a laminate for a cover window according to one embodiment of the present invention. In Fig. 1, the laminate (110) for a cover window may be laminated such that the acrylic coating layer (102) faces toward the substrate (103) and the hard coating layer (101) faces outward. In one embodiment, the hard coating layer (101) may be the outermost layer. In one embodiment, the laminate for a cover window may be applied to a display panel or the like. The laminate for the above cover window can be coated on a substrate (103) or glass including a touch optical film (PET film, PC film, PMMA film, PI film, polarizing film or other auxiliary film, etc.), and can also be directly coated on a display panel to implement a cover window. For example, the above-described substrate (103) may be a film of an optical film such as a polarizing film, an auxiliary film, or the like, or may be in the form of a panel. The laminate (110) for the cover window can be formed by sequentially laminating and coating a composition for forming an acrylic coating layer and a composition for forming a hard coating layer on the substrate (103), or by sequentially laminating a composition for forming a hard coating layer and a composition for forming an acrylic coating layer on the substrate (103). Specifically, the polysilsesquioxane may include a structural unit represented by Chemical Formula 1-1 and a structural unit represented by Chemical Formula 1-2, which are connected in a random order. In one embodiment, the polysilsesquioxane may include 1 to 100,000 structural units represented by Chemical Formula 1-1 and structural units represented by Chemical Formula 1-2, respectively. The content of the alkoxy group of -OR2 included in the structural unit represented by Chemical Formula 1-2 may be controlled by the content of the structural unit represented by Chemical Formula 1-2. In one embodiment, among the structural units represented by the chemical formula 1-1 and the structural units represented by the chemical formula 1-2, R1 is or It could be. In one embodiment, R2 among the structural units represented by the above chemical formula 1-2 is a methyl group or an ethyl group. In one embodiment, the polysilsesquioxane may contain 0.1 to 10 wt% of an alkoxy group represented by -OR2 in the above chemical formula 1-2. The hard coating layer may improve compatibility with the aliphatic urethane (meth)acrylate oligomer by using a polysilsesquioxane containing an alkoxy group in the above content range. In one embodiment, the polysilsesquioxane may be represented by chemical formula 1. <Chemical Formula 1> In the above chemical formula 1, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms, n and m are each independently an integer between 1 and 100,000, and, however, n and m only mean the number contained in one molecule of polysilsesquioxane represented by the above chemical formula 1, and the structural unit of the above chemical formula 1-1, which exists in n numbers, and the structural unit of the above chemical formula 1-2, which exists in m numbers, are not limited in their connection order and can be connected in a random order. In the present invention, n and m can be defined differently depending on the chemical formula. In one embodiment, the polysilsesquioxane represented by the above chemical formula 1 may be a random copolymer, block copolymer, etc. of the structural unit of the above chemical formula 1-1 and the structural unit of the above chemical formula 1-2, but is not limited thereto. In one embodiment, in the above chemical formula 1, n / m may be 1 to 50. Depending on the ratio of n / m, the ratio of ladder-type silsesquioxane units and open cage-type silsesquioxane units in the polysilsesquioxane may be adjusted, and by adjusting the n / m ratio within the above range, physical properties such as film strength after coating may be improved, while at the same time improving adhesion to the substrate (103) or the acrylic coating layer (102) and compatibility with the aliphatic urethane (meth)acrylate oligomer. In the above chemical formula 1, as defined, the structural unit of the above chemical formula 1-1 and the structural unit of the above chemical formula 1-2 may be arranged randomly or regularly. According to one embodiment, the polysilsesquioxane may include ladder-type silsesquioxane. According to another embodiment, the polysilsesquioxane may include ladder-type silsesquioxane structural units and open cage-type silsesquioxane structural units, and may not include random-type silsesquioxane structural units and cage-type silsesquioxane structural units. According to one embodiment, the proportion of ladder-type silsesquioxane in the polysilsesquioxane may be 15 mol% or more, for example, 19 mol% or more, in the total silsesquioxane. The more ladder-type silsesquioxane structures there are, the better the physical properties (e.g., film strength) of the coating film formed after coating. However, if the ladder-type silsesquioxane structures are too numerous, the coating film may become brittle or break easily. In addition, the more open-cage silsesquioxane structures there are, the higher the adhesion and the greater the compatibility with aliphatic urethane acrylate oligomers, but the strength may be weakened. In one embodiment, R1 in the above formula 1 is or It could be. In one embodiment, R2 in the above formula 1 is a methyl group or an ethyl group. In one embodiment, the composition for forming the hard coating layer may include (a) 100 parts by weight of the polysilsesquioxane; (b) 7 to 350 parts by weight of the aliphatic urethane (meth)acrylate oligomer; (c) 25 to 750 parts by weight of the oxygen-containing heterocyclic compound; (d) 0.1 to 5 parts by weight of a cationic photopolymerization initiator and a radical initiator; and (e) the remainder of an additive. The composition for forming the above hard coating layer may be solvent-free. The composition for forming the above hard coating layer can implement low curing of the hard coating layer and improve adhesion with the lower acrylic coating layer by including the above aliphatic urethane (meth)acrylate oligomer. The composition for forming the hard coating layer may contain 7 to 350 parts by weight, specifically, 9 to 100 parts by weight, and more specifically, 9.5 to 50 parts by weight, of the aliphatic urethane (meth)acrylate oligomer. By containing the aliphatic urethane (meth)acrylate oligomer in the above range, the composition for forming the hard coating layer may have a texture and surface strength similar to glass while exhibiting the effect of no warping or cracking under high temperature and high humidity reliability. In one embodiment, the aliphatic urethane (meth)acrylate oligomer may include at least one selected from the group consisting of aliphatic difunctional urethane acrylate, aliphatic trifunctional urethane acrylate, aliphatic hexafunctional urethane acrylate, silicone urethane acrylate, silicone urethane methacrylate, and combinations thereof. In one embodiment, the aliphatic urethane (meth)acrylate oligomer may be represented by the following chemical formula 3. <Chemical Formula 3> In the above chemical formula 3, A is a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent aromatic hydrocarbon group having 5 to 60 carbon atoms, or a divalent siloxane group, B is hydrogen or a methyl group, n and m are, each independently, integers from 1 to 20. Specifically, A in the above chemical formula 3 may be a group represented by at least one of the following chemical formula 3-1, the following chemical formula 3-2, and the following chemical formula 3-3. <Chemical Formula 3-1> <Chemical Formula 3-2> <Chemical Formula 3-3> In the above chemical formulas 3-1 to 3-3, R1 and R2 are each independently an alkyl group having 1 to 12 carbon atoms, n is an integer from 1 to 30, and * represents a connecting portion. In one embodiment, the compound represented by the above chemical formula 3 may be a compound represented by the following chemical formula 31 or the following chemical formula 32. <Chemical Formula 31> <Chemical Formula 32> In the above chemical formulas 31 and 32, B is hydrogen or a methyl group, PDMS is represented by the following structural formula: n is an integer from 1 to 30, and * indicates a connection point. The heterocyclic compound containing oxygen may be a compound having an oxetane ring having a hydroxyl group. For example, the heterocyclic compound containing oxygen may include at least one selected from the group consisting of 3-hydroxy methyloxetane, 3-methyl-3-hydroxy methyloxetane, 3-ethyl-3-hydroxy methyloxetane, and combinations thereof. The composition for forming the hard coating layer includes the heterocyclic compound containing oxygen, thereby alleviating curling and improving curing density. In one embodiment, the composition for forming the hard coating layer may contain 25 to 750 parts by weight, specifically, 25 to 200 parts by weight, and more specifically, 30 to 150 parts by weight, of a heterocyclic compound containing oxygen. By containing the heterocyclic compound containing oxygen in the above range, the composition for forming the hard coating layer can maintain an appropriate level of film strength to be suitable for the role of a cover window, while also alleviating curling and appropriately controlling viscosity. In one embodiment, when the weight ratio of the aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound in the composition for forming the hard coating layer is 1:1.5 to 7, the compatibility between the oxygen-containing heterocyclic compound and the aliphatic urethane (meth)acrylate oligomer is excellent, thereby improving the haze characteristics and, at the same time, enabling the crosslinking density to be appropriately controlled, thereby preventing deterioration of the physical properties of the coating film. The composition for forming the above hard coating layer may further include a cationic photopolymerization initiator, a radical initiator, or both. The cationic photopolymerization initiator is, for example, a sulfonium type such as triphenylsulfonium, diphenyl-4-(phenylthio)phenylsulfonium, iodonium such as diphenyliodonium or bis(dodecylphenyl)iodonium, diazonium such as phenyldiazonium, ammonium such as 1-benzyl-2-cyanopyrrinium or 1-(naphthylmethyl)-2-cyanopyrrinium, (4-methylphenyl)[4-(2-methylpropyl)phenyl]-hexafluorophosphate iodonium, bis(4-t-butylphenyl)hexafluorophosphate iodonium, diphenylhexafluorophosphate iodonium, diphenyltrifluoromethanesulfonate iodonium, triphenylsulfonium tetrafluoroborate, tri-p-toylsulfoniumhexafluorophosphate, tri-p-toylsulfonium trifluoromethanesulfonate and Fe cations such as (2,4-cyclopentadien-1-yl)[(1-methylethyl)benzene]-Fe and BF 4- , PF 6- , SbF 6- [BQ4] of the back - Examples include onium salts (wherein Q is a phenyl group substituted with at least two fluorine or trifluoromethyl groups), and at least one or more of these can be used, but are not limited thereto, and known compounds known as cationic photopolymerization initiators can be used. The radical initiator, for example, hydroxyketone series such as 1-hydroxy cyclohexylphenyl ketone (Irgacure 184), aminoketone series such as 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl) phenyl]-1-butanone (Irgacure 369), α-aminoacetophenone (Irgacure 907), benzyldimethyl ketal series such as benzyldimethyl ketal (Irgacure-651), phenyl bis(2,4,6-trimethyl benzoyl), Examples include bis-acyl phosphine series such as Irgacure 819, and mono-acyl phosphine series such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO), and at least one of these can be used, but is not limited thereto, and known compounds known as radical initiators can be used. The composition for forming the hard coating layer may further include at least one additive selected from the group consisting of an antioxidant, a leveling agent, a coating agent, and a combination thereof. In one embodiment, the thickness of the hard coating layer may be 10 μm to 200 μm, specifically, 30 μm to 200 μm, and more specifically, 50 μm to 100 μm. In one embodiment, the hardness of the hard coating layer may be 3H or greater while preventing warping and surface defects within the thickness range. In one embodiment, the composition for forming the acrylic coating layer may include (a) 100 parts by weight of a monofunctional component including a monofunctional (meth)acrylate monomer or oligomer; (b) 50 to 250 parts by weight of a polyfunctional (meth)acrylate monomer or oligomer; (c) 10 to 50 parts by weight of a polyfunctional thiol compound; (d) 0.1 to 50 parts by weight of one or more photopolymerization initiators; and (e) 0.1 to 50 parts by weight of a silane coupling agent. The composition for forming the above acrylic coating layer may further include (f) an additive including at least one antioxidant, UV stabilizer, etc. The composition for forming the above acrylic coating layer may be solvent-free. The composition for forming the above acrylic coating layer can reduce shrinkage during photocuring, prevent deformation due to shrinkage, and achieve excellent dimensional stability. The above monofunctional (meth)acrylate-based oligomer may be a monofunctional urethane (meth)acrylate-based oligomer, and specifically, may include at least one selected from the group consisting of polybutadiene urethane (meth)acrylate oligomer, epoxy urethane (meth)acrylate oligomer, polyester urethane (meth)acrylate oligomer, polyether urethane (meth)acrylate oligomer, and combinations thereof. The above monofunctional acrylate monomer may specifically include at least one selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, hydroxyethyl (meth)acrylate, and combinations thereof. The composition for forming the acrylic coating layer may contain 50 to 250 parts by weight, specifically, 70 to 200 parts by weight, of the multifunctional (meth)acrylate monomer or oligomer. By containing the multifunctional (meth)acrylate monomer or oligomer in the above range, the composition for forming the acrylic coating layer may improve the hardness and durability of the coating layer. The above multifunctional (meth)acrylate oligomer may be a multifunctional urethane (meth)acrylate oligomer, and specifically, may include at least one selected from the group consisting of polybutadiene urethane (meth)acrylate oligomer, epoxy urethane (meth)acrylate oligomer, polyester urethane (meth)acrylate oligomer, polyether urethane (meth)acrylate oligomer, and combinations thereof. The above multifunctional (meth)acrylate monomer may specifically be a trifunctional or higher (meth)acrylate, and may include at least one selected from the group consisting of, for example, pentaerythritone dedrakis(3mercaptobutyrate), trishydroxyethylisocyanurate tri(meth)acrylate, trimethylpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and combinations thereof. The composition for forming the above acrylic coating layer can prevent crosslinking density and surface curing degradation due to oxygen interference by including the above multifunctional thiol compound. The composition for forming the acrylic coating layer may contain 10 to 50 parts by weight of the multifunctional thiol compound, specifically, 15 to 40 parts by weight. The composition for forming the acrylic coating layer may increase adhesive strength by containing the multifunctional thiol compound in the above range. Examples of the above multifunctional thiol compound may include at least one selected from the group consisting of 1,4-bis(3-mercaptobutyryloxy)butane), 1,3,5-tris(3-mercaptobutyryloxetyl)-1,3,5triazine-2,4,6(1H,3H,5H)-trione, pentaerythritone tetrakis(3-mercaptobutyrate), and combinations thereof. The composition for forming the above acrylic coating layer may contain 0.1 to 50 parts by weight, specifically, 1 to 20 parts by weight, of one or more photopolymerization initiators. By further containing the photopolymerization initiator within the above range, the composition for forming the above acrylic coating layer may have excellent efficiency of the photoinitiation reaction. Examples of the photopolymerization initiator include hydroxyketone series such as 1-hydroxy cyclohexylphenyl ketone (Irgacure 184), aminoketone series such as 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl) phenyl]-1-butanone (Irgacure 369) and α-aminoacetophenone (Irgacure 907), benzyldimethyl ketal series such as benzyldimethyl ketal (Irgacure-651), phenyl bis(2,4,6-trimethyl benzoyl), It may include at least one selected from the group consisting of bis-acyl phosphine series such as Irgacure 819, mono-acyl phosphine series such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO), and combinations thereof. The above acrylic coating layer can improve interfacial adhesion with the hard coating layer by the above silane coupling agent. The composition for forming the acrylic coating layer may contain 0.1 to 50 parts by weight of the silane coupling agent, specifically, 0.5 to 30 parts by weight. By containing the silane coupling agent in the above range, the composition for forming the acrylic coating layer can improve interfacial adhesion with the hard coating layer. The above silane coupling agent may be in the form of an oligomer containing 2 to 20 structural units represented by the following chemical formula 2. <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5. The above heteroalkylene group is a structure including at least one heteroatom replacing a carbon atom in alkylene, and the heteroatom includes at least one selected from the group consisting of -O-, -S-, and combinations thereof. In one embodiment, X in the above chemical formula 2 may be a methyl group or a phenyl group. The weight average molecular weight of the above silane coupling agent may be 1,000 to 2,000. When the silane coupling agent has a weight average molecular weight within the above numerical range, it has low volatility and many reaction sites with the resin, thereby achieving improved adhesion between the upper hard coating layer and the lower substrate. In one embodiment, -OR3 in the above chemical formula 2 may be selected from the group consisting of a hydroxyl group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a pentyloxy group, a hexyloxy group, and combinations thereof. In one embodiment, the silane coupling agent may be a compound represented by the following chemical formula 21. <Chemical Formula 21> In the above chemical formula 21, R3 is an alkyl group having 1 to 20 carbon atoms, L3 is an alkylene group having 1 to 10 carbon atoms, m2 and n2 are each independently an integer from 1 to 10, and provided that n2 and m2 only mean the number contained in one molecule of the compound represented by the chemical formula 21, and the connection order of the n2 structural units and the m2 structural units is not limited and can be connected in a random order. The composition for forming the above acrylic coating layer may further include a silicone-based additive or an acrylic-based additive, as needed or depending on the properties required for the intended use. Examples of silicone-based additives include BYK-300, BYK-301, BYK-302, BYK-331, BYK-335, BYK-306, BYK-330, BYK-341, BYK-344, BYK-307, BYK-333, BYK-310, etc., and examples of acrylic-based additives include BYK-340, BYK-350, BYK-352, BYK-354, BYK-355, BYK-356, BYK-358N, BYK-359, BYK-361N, BYK-380N, BYK-381, BYK-388, BYK-390, BYK-392, BYK-394, etc. The composition for forming the above acrylic coating layer can further improve the flatness of the surface of the coating film by further including the silicone-based additive and / or the acrylic additive. In one embodiment, the composition for forming the acrylic coating layer for implementing the acrylic coating layer may include methacrylate to control the mixing ratio of the monofunctional and polyfunctional urethane (meth)acrylate oligomer and the monofunctional and polyfunctional (meth)acrylate, and to slow down the reaction rate. In one embodiment, the acrylic coating layer formed by coating the composition for forming the acrylic coating layer and then photocuring may have a shrinkage rate of 3% or less before and after photocuring. The laminate for the above cover window may have a Young's modulus of 0.1 GPa to 15 GPa. In one embodiment, the modulus of the acrylic coating layer may be from 10 MPa to 5000 MPa, specifically from 20 MPa to 2000 MPa. By ensuring that the acrylic coating layer has a modulus within the above range, it is possible to facilitate shock absorption from external impact while ensuring sufficient film strength in the final coating film. In one embodiment, the thickness of the acrylic coating layer may be 10 µm to 600 µm, specifically, 50 µm to 600 µm, and more specifically, 100 µm to 300 µm. The laminate for the above cover window can replace existing glass, UTG (ultra-thin glass) or CPI (colorless polyimide) film by forming a thick coating film through photo-curing of the acrylic coating layer. The laminate for the above cover window can absorb external impact by laminating the hard coating layer on one side of the acrylic coating layer having a predetermined modulus, and can overcome the thickness limitation of the existing hard coating layer. In addition, since the composition of each layer contains an oligomer binder capable of improving adhesion, excellent adhesion can be achieved even when the composition of each layer is used without an additional process such as primer coating or the addition of an additional layer, and a free-standing specimen without warping or cracking can be produced even in a high-temperature, high-humidity environment. By coating the hard coating layer on the acrylate layer having a predetermined modulus, the physical properties of the hard coating layer applicable to next-generation displays can be maintained while ensuring flexibility. The polysilsesquioxane-based hard coating layer-forming composition defined above has a texture and surface strength similar to glass, and thus can be used as the outermost coating layer. By laminating such a hard coating layer with the acrylic coating layer and using it, resistance to external impact can be enhanced. In addition, when simply producing a single layer of the hard coating layer having a thickness usable as a cover window and photocuring it, a problem may arise in that curing is not performed well at a distance from a light source. However, the laminate for the cover window can prevent damage to the hard coating layer by disposing the acrylic coating layer having viscoelasticity under the hard coating layer, thereby absorbing external stress, thereby maintaining mechanical properties without cracking even under harsh deformation such as folding, and is therefore very useful for application as a cover window. The composition for forming the hard coating layer can be rapidly cured through a cationic polymerization reaction or a radical polymerization reaction with irradiated light energy. The Lewis acid generated from the cationic photopolymerization initiator attacks and rings open the oxygen atoms of the oxygen-containing heterocyclic compound and the oxirane ring in the polysilsesquioxane, and by these continuously progressing, a cured product having a three-dimensional network structure can be formed. When the polysilsesquioxane contains an oxirane ring, it can exhibit the effect of alleviating curling. The oxygen-containing heterocyclic compound acts as a reaction diluent to lower the overall viscosity of the composition for forming the hard coating layer, thereby facilitating coating, and also improves the compatibility between the aliphatic urethane (meth)acrylate and the polysilsesquioxane, thereby forming a transparent coating film. The above aliphatic urethane (meth)acrylate forms a network structure through a radical reaction by a radical initiator, and is inserted into the polysilsesquioxane to lower the crosslinking density, thereby controlling the curl of the hard coating layer. For this reason, the adhesion between the polymer substrate and the hard coating layer, which was difficult to achieve with the conventional polysilsesquioxane polymer binder during curing, can be improved by mixing the aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound at an appropriate ratio. Accordingly, the adhesion to the underlying acrylic coating layer can be improved, the flexibility can be improved while maintaining the surface strength of the polysilsesquioxane, and the production of a coating film without optical properties and appearance deformation such as warping or cracking even after high temperature and high humidity reliability can be made possible. For example, by adding the heterocyclic compound containing oxygen in an amount of 25 to 750 parts by weight relative to 100 parts by weight of the polysilsesquioxane, the compatibility with the aliphatic urethane (meth)acrylate oligomer can be improved, thereby preventing the haze characteristics from being improved and, at the same time, the crosslinking density can be appropriately controlled to prevent the deterioration of the physical properties of the coating film. In addition, if the aliphatic urethane (meth)acrylate oligomer is not included in the composition for forming the hard coating layer, high film strength can be achieved, but surface defects such as low impact resistance and easy breakage from external impact may occur. On the other hand, if the aliphatic urethane (meth)acrylate oligomer is included in an excessive amount exceeding the aforementioned content range, compatibility can be reduced, which can cause haze damage or reduce the film strength of the coating film. In addition, the acrylic-forming composition constituting the acrylic coating layer can improve adhesion with the hard coating layer by using the silicone coupling agent capable of maintaining a bond with the hard coating layer-forming composition including the polysilsesquioxane. The oligomer-type silane coupling agent has more reactive sites than low-molecular-weight silane coupling agents, and thus can induce more chemical bonds between the acrylic coating layer and the hard coating layer, and has a large molecular weight, so that a film having high film strength can be formed. Therefore, even under high-temperature and high-humidity environmental conditions, delamination between layers does not occur, and deterioration of physical properties such as warping, cracking, and deterioration of adhesive strength caused by interfacial delamination can be prevented. The laminate for the above cover window can have excellent adhesion and excellent hardness, surface properties, bending properties, and viscoelastic properties, all with only the laminated structure of the acrylic coating layer and the hard coating layer, without adding additional layers, auxiliary layers, or adhesive layers. In one embodiment, the thickness ratio of the acrylic coating layer and the hard coating layer in the laminate for the cover window may be 20:1 to 1:4. The hardness, surface properties, bending properties, and viscoelastic properties of the laminate for the cover window including the acrylic coating layer and the hard coating layer within the thickness ratio range are excellent. In one embodiment of the present invention, Polysilsesquioxane; aliphatic urethane (meth)acrylate oligomer; and a heterocyclic compound containing oxygen; The weight ratio of the above aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound and the above aliphatic urethane (meth)acrylate oligomer is 1:1.5 to 7. A composition for forming a hard coating layer for a cover window is provided. In one embodiment, the polysilsesquioxane may include a structural unit represented by Chemical Formula 1-1 and a structural unit represented by Chemical Formula 1-2. <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms. A detailed description of the composition for forming the above hard coating layer is as described in the laminate for the above cover window. In one embodiment of the present invention, A composition for forming an acrylic coating layer for a cover window is provided, which comprises a silane coupling agent in the form of an oligomer represented by the following chemical formula 2. <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5. A detailed description of the composition for forming the above acrylic coating layer is as described in the laminate for the above cover window. Hereinafter, examples and comparative examples of the present invention are described. The following examples are merely examples of the present invention, and the present invention is not limited to the examples described below. (ingredient) Reactive oxetane compound: SYNASIA S-101 Cationic photopolymerization initiator: PI-CAT-6974 from SYNASIA Radical initiator: Yuwon Intec TPO Mine generator: HERAEUS NIN Leveling agent: BYK Instruments BYK-333, BYK-UV3505 Multifunctional (meth)acrylate: DKS NEWFRONTIER MF-001 Multifunctional urethane acrylate oligomer: Kempton CHTF-5601A Monofunctional (meth)acrylate monomer: SARTOMER SR506 Monofunctional (meth)acrylate (-OH): ALDRICH HEA Radical photoinitiator 1: BASF IRGACURE 184 Radical photoinitiator 2: Yuwon Intec TPO Thiol compounds: SHOWA DENKO KARENZ MT PE1 (Example) Manufacturing Example 1: Synthesis of polysilsesquioxane In a flask equipped with a condenser and a stirrer, 32 g of distilled water and 100 g of methanol were added, and while maintaining the temperature at -4 ℃, 261.61 g of 3-(trichlorosilyl)propylmethacrylate was slowly added dropwise over 10 minutes. The mixture was stirred for an additional 20 minutes, 500 g of toluene was added dropwise, the temperature was raised to room temperature, and the mixture was stirred for an additional 10 minutes (simultaneous acquisition of Si-OH and Si-alkoxy (OR2)). Thereafter, 24.64 g of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane was added dropwise and stirred for 10 minutes. To the above reaction solution, 10 g of a 20 wt% aqueous solution of Na2CO3 was added dropwise at a time, the temperature was raised to 100°C, and a condensation reaction was performed for 1 day. The reaction solution was purified by separating it into an aqueous layer and a toluene layer, and after confirming that the pH was neutral, the toluene layer was decompressed under vacuum to remove all toluene, thereby obtaining polysilsesquioxane. The obtained polysilsesquioxane had a linear structure, a weight-average molecular weight of 10,000, and no unreacted monomers. The weight-average molecular weight is the polystyrene-converted average molecular weight measured using gel permeation chromatography. The obtained silsesquioxane polymer was analyzed by a decomposition temperature measurement method using a TGA (Thermo Gravimetric Analyzer) and the residual ratio of alkoxy (methoxy) was 3 wt%, and the ratio of n:m was approximately 2:1 as analyzed by 1H-NMR. The residual ratio of alkoxy was measured by confirming the decomposition amount of the alkoxy group that was offset by condensation in the range of 150°C to 250°C using TGA, and the ratio of n:m was measured by calculating the area integral of Si-C derived from the functional groups of repeating units n and m and the C partial integral of Si-OCH3 appearing only in repeating unit m. Manufacturing Example 2: Synthesis of aliphatic urethane acrylate oligomer In a four-hole beaker-type reactor, hydroxypropyl polydimethylsiloxane (HPPDMS, 215 g) represented by the following chemical formula 4, a diluent (isobornyl acrylate (IBOA), 258 g), a catalyst (dibutyl tin dilaurate (DBTDL), 0.05 g), and a heat stabilizer (dibutyl hydroxytoluene (butylated hydroxytoluene, BHT), 0.54 g) were added, and then uniformly mixed for 1 hour while raising the temperature to 60°C. After that, the internal temperature of the reactor was raised to 85 ℃, and when the temperature stabilized, isophorone diisocyanate (IPDI) was slowly dropped for 20 minutes to synthesize a silicone-modified urethane prepolymer represented by the following chemical formula 41. After that, while maintaining the temperature of the reactor at 85 ㅤ℃, 10.3 g of hydroxyethyl acrylate (HEA) was added to introduce an acrylate reactor at the end of the urethane prepolymer. After confirming that the -NCO characteristic peak completely disappeared through Fourier transform infrared spectroscope (FTIR, Agilent, Cary 660) analysis during the reaction, the reaction was terminated, and a polydimethylsiloxane-modified urethane acrylate having an acrylate group represented by the following chemical formula 42 was synthesized as an aliphatic urethane acrylate oligomer. <Chemical Formula 4> In the above chemical formula 4, n is an integer from 1 to 10 (hydroxypropylpolydimethylsiloxane is n=2). <Chemical Formula 41> In the above chemical formula 41, PDMS is represented by the following structural formula. n is 15, and * indicates the connection point. <Chemical Formula 42> In the above chemical formula 42, Y is hydrogen, PDMS is represented by the following structural formula. n is 15, and * indicates the connection point. Example 1-9 and Comparative Example 1-9: Preparation of a composition for forming a hard coating layer A composition for forming a hard coating layer was prepared by mixing the polysilsesquioxane prepared in Manufacturing Example 1, the polydimethylsiloxane-modified urethane acrylate prepared in Manufacturing Example 2 as an aliphatic urethane acrylate oligomer, the reactive oxetane compound as a heterocyclic compound containing oxygen, and a cationic photopolymerization initiator and a radical initiator in the contents shown in Tables 1 to 2 and 4 to 5 below (Examples 1-9 and Comparative Examples 1-9). Example 10-13: Preparation of a composition for forming a hard coating layer A composition for forming a hard coating layer was prepared by mixing polysilsesquioxane represented by the structural formula below, a polydimethylsiloxane modified urethane acrylate prepared in Manufacturing Example 2 as an aliphatic urethane acrylate oligomer, a reactive oxetane compound as a heterocyclic compound containing oxygen, a cationic photopolymerization initiator, and a radical initiator in the contents described in Table 3 below (Examples 10-13). Polysilsesquioxane: MA 0735: methacryl POSS cage mixture (manufacturer: Hybridplastics) Evaluation Example 1 The compositions for forming a hard coating layer prepared in the above Examples 1-13 and Comparative Examples 1-9 were photocured at 2,000 mJ / cm2 using a 300 mW / cm2 metal-halide lamp to form a hard coating layer film. The physical properties were evaluated as follows and are listed in Tables 1 to 5. (Young's modulus measurement) 1) Method of making a specimen: Laser cut the coating film coated with a thickness of 100㎛ into a size of 1 cm (width) X 10 cm (height). 2) Pull the above-mentioned specimen through the Universal Testing Machine (UTM) at a speed of 50 mm / min. 3) At this time, the measured Young's modulus value is obtained. (Transmittance measurement) Measurements were made using a colorimeter (Minolta CM-3700A) in transmission mode. Measurements were made five times per sample, and the average value was reported. (measuring the membrane strength) The strength was measured under a load of 1 kg according to ASTM D3363 using the following method. 1. Polish the core so that the tip is flat and the angle is sharp, leaving the core exposed about 3 to 4 mm in a cylindrical shape. 2. Place the pencil lead on the surface of the film at an angle of about 45 degrees and move it 15 mm at a speed of 100 mm / min. 3. After performing this 5 times, erase the middle of the line with an eraser and if there are no abnormalities more than 3 times out of 5, mark it as the corresponding hardness. ※ The pencil is re-sharpened after one test. ※ Pencil hardness: 9B~3B → 2B → 1B → HB → F → H → 2H → 3H~9H. (Interfacial adhesion) The interfacial adhesion to the acrylic coating layer was evaluated. According to ASTM-D3359, 25 scratches were made in a grid pattern at 2 mm intervals with a cutter blade, and adhesive tape was applied on top of them. o The coating layer surface was visually inspected to see if it adhered to the adhesive tape and came off by peeling it off in the direction of the peel. (0 indicates the lowest adhesiveness, and 5B indicates the best adhesiveness.) 5B: The cut surface is clean and the grid squares are not separated. 4B: Coating fragments separated at intersections (less than 5% of grid area) 3B: Small pieces of coating are separated at the intersection of the cut sections along the edges (5-15% of the grid area). 2B: The edges of the coated cut surface and some of the square are separated (15-35% of the grid area). 1B: The coating is peeled off significantly along the cut edge and the squares are separated (35-65% of the grid area). 0: More delaminated and separated than 1B (more than 65% of the grid area) (Initial curl) Place a specimen manufactured with a width of 73 mm, a height of 150 mm, and a thickness of 50 μm on a flat surface (on a table), and measure the maximum height of the point rising from the flat surface. Example 1 Example 2 Example 3 Example 4 Example 5 Polysilsesquioxane (SSQ) 63.35 8.44 8.76 8.24 8.7 Aliphatic urethane acrylate oligomer 4.99 9.819.59.89.8 Reactive oxetane compound 29.329.329.219.539 Sub total 97.597.597.497.597.5 Cation photoinitiator 0.50.40.40.40.4 Radical photoinitiator 0.00.10.20.10.1 Photo acid Generator 0.9 0.9 0.8 0.9 0.9 Leveling agent 1.11 11 21.11 1 BYK-360 5 00000 Total 100 100 100 100 Young's modulus (Gpa) 5.3 2.8 1.9 4.5 2.4 Permeability 91.2 9 1.7 9 1.3 3 9 1.4 9 1.6 Membrane strength (1 kg) 4 H 3 H 3 H 4 H 3 H Interfacial adhesion (acrylic coating layer) 1~2 B 5 B 5 B 3 B 4 B Initial curl (mm) 10 6 4 10 or less 10 or less 85℃ 85% / 240hr-3 or less 10 or less 10 or less 3 or less Example 6 Example 7 Example 8 Example 9 Polysilsesquioxane (SSQ) 39 29.39.7 9.7 Aliphatic urethane acrylate oligomer 9.8 9.8 19.5 29.2 Reactive oxetane compound 48.7 58.4 68.2 58.5 Sub total 97.5 97.5 97.4 97.4 Cation photoinitiator 0.4 0.4 0.4 0.3 Radical photoinitiator 0.10.10.2 0.3 Photoacid generator 0.9 0.9 0.8 0.7 Leveling agent 1.11.11.2 1.3 BYK-36 0 5 0000 Total 100 100 100 100 Young's modulus (Gpa) 1.5 1.5 0.8 0.7 Permeability 91.6 9 2 9 0.2 9 0.7 Membrane strength (1 kg) 2 HHB 7 B or less 7 B Below the interface adhesion (acrylic coating layer) 4B 4B 4B 4B Initial curl (mm) 10 or less 3 or less 00 85℃ 85% / 240hr 3 or less 3 or less 3 or less 3 or less Example 10 Example 11 Example 12 Example 13 Polysilsesquioxane (SSQ) 58.4 48.7 48.7 39 Aliphatic urethane acrylate oligomer 9.8 19.5 9.8 9.8 Reactive oxetane compound 29.3 29.2 39 48.7 Sub total 97.5 97.4 97.5 97.5 Cation photoinitiator 0.4 0.4 0.4 0.4 Radical photoinitiator 0.10 20.10.1 Photoacid generator 0.9 0.8 0.9 0.9 Leveling agent 1.11 21.11 BYK-360 50000 Total 100 100 100 100 Young's modulus (Gpa) 3.2 2.12.4 1.9 Permeability 90.1 91.1 90.0 390.1 1 Membrane strength (1kg)4H2H3H2HInterfacial adhesion (acrylic coating layer)01~2B1~2B0Initial curl (mm)2010101085℃ 85% / 240hrCrack occurrenceCrack occurrenceCrack occurrenceCrack occurrence Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Polysilsesquioxane (SSQ) 63.3 58.4 48.7 68.2 48.7 Aliphatic urethane acrylate oligomer 65 39 87.89 778 Reactive oxetane compound 32.5 29.29 787.89 7 Sub total 97.5 97.2 97.5 97.5 97.5 Cation photoinitiator 0.5 0.4 0.5 0.5 0.4 Radical photoinitiator 0.0 0.3 00 0.1 Photoacid generator 10.8 1 10.9 Leveling agent 11.3 1 1 1 BYK-360 5 00000 Total 100 100 100 100 Young's modulus (Gpa) Not measurable 1.4 Not measurable 0.2 Not measurable Transmittance 90.4 291.2 90.05 9190.11 Membrane strength (1kg) 4H3B 5H6B 5H Interfacial adhesion (acrylic coating layer) 05B 0 04B Initial curl (mm) 300 20 1016 85℃ 85% / 240hr Crack occurrence (reverse curl) 10 Crack occurrence (reverse curl) 5 or less Twist Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Polysilsesquioxane (SSQ) 9.7 3 2.5 6 8.2 5 8.5 Aliphatic urethane acrylate oligomer 9.8 0 1 9.5 2 9.2 Reactive oxetane compound 7 8 6 5 9.7 9.7 Sub total 9 7.5 9 7.5 9 7.4 9 7.4 Cation photoinitiator 0.4 0.5 0.4 0.3 Radical photoinitiator 0.1 0 0.2 0.3 Photoacid generator 0.9 1 0.8 0.7 Leveling agent 1.1 1 1.2 1.3 BYK-360 5 0000 Total 1 0 1 0 1 0 1 0 Young's modulus (Gpa) 0.2 0.5 21.6 Permeability 9 1.3 9 1.8 2 9 0.0 2 8 9.97 Membrane strength (1 kg) 6 B Below F3H2H interface adhesion (acrylic coating layer) 4B04B4B initial curl (mm) 0510685℃ 85% / 240hr 5 or less 5 or less Twist Twist From the results in Tables 1 to 5, the hard coating layer of Example 1-13 has higher surface strength and modulus than the hard coating layer of Comparative Example 1-9, and can maintain low curl without appearance deformation even after high temperature and high humidity reliability. Examples 14-19 and Comparative Examples 10-14: Preparation of composition for forming an acrylic coating layer A composition for forming an acrylic coating layer was prepared according to the contents described in Tables 7 and 8 for the following compounds. Silane coupling agent: A silane coupling agent was used in which each substituent of the following chemical formula 2 was defined as described in Table 6 below. <Chemical Formula 2> Silane coupling agent type L1 L2 b R3 X g / mol KR-513 Direct bond Direct bond 0 Methyl acrylate / methyl 1,484 KR-517 Direct bond Direct bond 0 Methyl / ethyl epoxy 1,984 KR-516 Direct bond Direct bond 0 Methyl epoxy / methyl 1,618 KBM-303 Direct bond Direct bond 2 Methyl epoxy 246.4 KBM-403 Direct bond Direct bond 3 Methyl epoxy 236.3 KBM-503 Direct bond Direct bond 3 Methyl meth(acrylate) 248.4 The compositions for forming an acrylic coating layer prepared in the above Examples 14-19 and Comparative Examples 10-14 were photocured at 2,000 mJ / cm2 using a 300 mW / cm2 metal-halide lamp to form an acrylic coating layer film. The physical properties were evaluated as follows and are listed in Tables 7 and 8. Evaluation Example 2 The evaluations for Young's modulus, permeability, membrane strength, initial curl, and curl after 85℃ 85% / 240hr are the same as in Evaluation Example 1. (UV curing shrinkage) Using the DHR-3 equipment from TA instruments, UV curing shrinkage was measured by examining gap size changes before and after UV curing. Shrinkage was measured using the fast oscillation step method under the following conditions. Geometry: 8mm parallel plate Strain: 1% Frequency: 1Hz Photocuring energy: 2,000mJ / ㎠ @ (365nm LED lamp 200mW / ㎠) (Hayes) Measurements were made using a colorimeter (Minolta CM-3700A) in transmission mode. Measurements were made five times per sample, and the average value was reported. (Yellowness: YI) Measurements were made using a colorimeter (Minolta CM-3700A) in transmission mode. Measurements were made five times per sample, and the average value was reported. Example 14 Example 15 Example 16 Example 17 Example 18 Example 19 Multifunctional (meth)acrylate monomer 23.3 23.1 22.9 22.5 23.1 23.1 Multifunctional urethane acrylate oligomer 26.2 26 25.8 25.3 26 26 Monofunctional (meth)acrylate monomer 32.9 32.6 32.3 1.8 32.6 32.6 Monofunctional (meth)acrylate (-OH) 4.9 4.9 4.9 4.9 4.9 4.8 4.9 4.9 Sub total 87.3 86.6 85.9 84.4 86.6 86.6 Radical photoinitiator 11.7 1.7 1.7 1.7 1.7 1.7 Radical photoinitiator 20.40.40.40.40.40.4 Thiol compound 8.88.78.58.58.78.7 Leveling agent 0.90.90.90.80.90.9KR-513 (Formula 2, x: acrylic group) 0.91.72.64.200KR-517 (Formula 2, x: epoxy group) 00001.70KR-516 (Formula 2, x: epoxy / methyl) 000001.7Total 100100100100100100UV curing shrinkage (%) 2.82.72.62.62.32.2Young's modulus (Gpa) 2.82.72.82.72.02.0Transmittance92.2492.2192.1892.4291.8391.51HAZE0.270.260.250.220.290.24YI1.231.061.091.121.51.48Membrane strength (1kg)HHHHB2BInterfacial adhesion (acrylic coating layer)5B5B5B5B3~4B3~4BInitial curl (mm)11111185℃ 85% / 240hr after curl (mm)3 or less3 or less3 or less3 or less10 or less10 or less Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Comparative Example 14 Multifunctional (meth)acrylate monomer 23.5 22.9 22.9 22.9 22.9 Multifunctional urethane acrylate oligomer 26.4 25.8 25.8 25.8 25.8 Monofunctional (meth)acrylate monomer 33.2 32.3 332.3 332.3 Monofunctional (meth)acrylate (-OH) 5 4.9 4.9 4.9 4.9 Sub total 88.1 85.9 85.9 85.9 85.9 Radical photoinitiator 11.8 1.7 1.7 1.7 Radical photoinitiator 20.4 0.4 0.4 0.4 0.4 Thiol type Compound 8.88.58.58.58.5Leveling agent 0.90.90.90.90.9KR-513 (silane coupling agent) 00000KBM-303 (low molecular weight silane coupling agent) 02.6000KBM-403 (low molecular weight silane coupling agent) 002.600KBM-503 (low molecular weight silane coupling agent) 0002.60BYK-UV357 000002.6Total 100100100100100UV curing Shrinkage (%) 2.8 2.8 2.8 2.8 2.8 3.1 Young's modulus (Gpa) 2.7 2.3 2.2 2.2 2.2 Permeability 9 2.1 3 9 1.9 9 1.9 5 9 1.8 7 9 2.1 HAZE 0.3 0.4 0.4 0.3 0.3 YI 1.1 1.3 1.4 1.3 8 1.1 Membrane strength (1kg) HB~HBB~HB HBB~HB Interfacial adhesion (acrylic coating layer) 0~1B 0~1B 0~1B 0~1B 0~1B Initial curl (mm) 11111 Curl after 85℃ 85% / 240hr (mm) 3 or less 3 or less 3 or less 3 or less 3 or less From the results in Tables 7 and 8, the acrylic coating layer of Examples 14-19 has superior interfacial adhesion with the hard coating layer of the topcoat and high surface strength and modulus compared to the acrylic coating layer of Comparative Examples 10-14. Example 20: Laminate for cover window A laminate for a cover window having a structure as shown in Fig. 1 was manufactured by sequentially coating the composition for forming an acrylic coating layer of Example 15 and the composition for forming a hard coating layer of Example 2 on a substrate. Comparative Example 15: Laminate for cover window A laminate for a cover window having a structure as shown in Fig. 1 was manufactured by sequentially coating the composition for forming an acrylic coating layer of Example 15 and the composition for forming a hard coating layer of Comparative Example 10 on a substrate. Comparative Example 16: Laminate for cover window A laminate for a cover window having a structure as shown in Fig. 1 was manufactured by sequentially coating the composition for forming an acrylic coating layer of Example 15 and the composition for forming a hard coating layer of Comparative Example 1 on a substrate. Comparative Example 17: Laminate for cover window A laminate for a cover window having a structure as shown in Fig. 1 was manufactured by sequentially coating the composition for forming an acrylic coating layer of Comparative Example 10 and the composition for forming a hard coating layer from Comparative Example 1 on a substrate. Evaluation Example 3 The laminates for cover windows manufactured in Example 20 and Comparative Examples 15-17 were evaluated as follows, and the results are shown in Table 9 below. The measurement methods for the evaluated physical properties are the same as in Evaluation Example 1 and Evaluation Example 2. Example 20 Comparative Example 15 Comparative Example 16 Comparative Example 17 Young's modulus (Gpa) 3.23 3.4 3.3 Permeability 92.74 91.92 92.39 2.7 HAZE 0.20.30.20.33 YI 1.48 1.45 1.3 1.28 Membrane strength 3 H 3 H 4 H 4 H Interfacial adhesion 5 B 000 Initial curl (mm) 11 Twist (10 or more) Twist (10 or more) 85℃ 85% / 240hr 3 or less 3 or less Interlayer peeling Interlayer peeling From the results in Table 9, it was confirmed that Example 20 had superior interfacial adhesion compared to Comparative Examples 15-17, and as a result, it was confirmed that the initial curl characteristics and curl characteristics after 240 hours of curing under high temperature and high humidity conditions were superior. While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the exemplary embodiments disclosed herein, and that various modifications may be made by those skilled in the art within the scope of the technical spirit of the invention. Furthermore, even if the operational effects of the configurations of the invention have not been explicitly described and explained while describing the exemplary embodiments of the invention, it is also to be understood that the effects predictable by the configurations should be acknowledged.

Claims

1. A hard coating layer comprising a cured product of a composition for forming a hard coating layer comprising polysilsesquioxane; an aliphatic urethane (meth)acrylate oligomer; and a heterocyclic compound containing oxygen; and An acrylic coating layer comprising a cured product of a composition for forming an acrylic coating layer comprising a silane coupling agent in the form of an oligomer; In the composition for forming the hard coating layer, the weight ratio of the aliphatic urethane acrylate oligomer and the oxygen-containing heterocyclic compound is 1:1.5 to 7. Laminate for cover window.

2. In paragraph 1, The above polysilsesquioxane comprises a structural unit represented by Chemical Formula 1-1 and a structural unit represented by Chemical Formula 1-2. Laminate for cover window: <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms.

3. In paragraph 1, The above polysilsesquioxane contains 0.1 to 10 wt% of an alkoxy group represented by -OR2 in the above chemical formula 1-2. Laminate for cover window.

4. In paragraph 1, The above polysilsesquioxane is represented by chemical formula 1. Laminate for cover window: <Chemical Formula 1> In the above chemical formula 1, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms, n and m are each independently an integer between 1 and 100,000, and, however, n and m only mean the number contained in one molecule of polysilsesquioxane represented by the above chemical formula 1, and the structural unit of the above chemical formula 1-1, which exists in n numbers, and the structural unit of the above chemical formula 1-2, which exists in m numbers, are not limited in their connection order and can be connected in a random order.

5. In paragraph 1, The composition for forming the hard coating layer comprises (a) 100 parts by weight of polysilsesquioxane; (b) 7 to 350 parts by weight of aliphatic urethane (meth)acrylate oligomer; (c) 25 to 750 parts by weight of a heterocyclic compound containing oxygen; (d) 0.1 to 5 parts by weight of a cationic photopolymerization initiator and a radical initiator; and (e) the remainder of an additive. Laminate for cover window.

6. In paragraph 1, The composition for forming the above hard coating layer is a solvent-free type. Laminate for cover window.

7. In paragraph 1, The above aliphatic urethane (meth)acrylate oligomer is represented by the following chemical formula 3: Laminate for cover window: <Chemical Formula 3> In the above chemical formula 3, A is a divalent aliphatic hydrocarbon group having 1 to 12 carbon atoms, a divalent aromatic hydrocarbon group having 5 to 60 carbon atoms, or a divalent siloxane group, B is hydrogen or a methyl group, n and m are integers from 1 to 20.

8. In paragraph 7, In the above chemical formula 3, A is a group represented by at least one of the following chemical formulas 3-1, 3-2 and 3-3. Laminate for cover window: <Chemical Formula 3-1> <Chemical Formula 3-2> <Chemical Formula 3-3> In the above chemical formulas 3-1 to 3-3, R1 and R2 are each independently an alkyl group having 1 to 12 carbon atoms, n is an integer from 1 to 30, and * represents a connecting portion.

9. In paragraph 7, The compound represented by the above chemical formula 3 is a compound represented by the following chemical formula 31 or the following chemical formula 32. Laminate for cover window: <Chemical Formula 31> <Chemical Formula 32> In the above chemical formulas 31 and 32, B is hydrogen or a methyl group, PDMS is represented by the following structural formula: n is an integer from 1 to 30, and * indicates a connection point.

10. In paragraph 1, The above oxygen-containing heterocyclic compound is a compound having an oxetane ring with a hydroxyl group. Laminate for cover window.

11. In paragraph 1, The composition for forming the above acrylic coating layer is: (a) 100 parts by weight of a monofunctional component including a monofunctional (meth)acrylate monomer or oligomer; (b) 50 to 250 parts by weight of a polyfunctional (meth)acrylate monomer or oligomer; (c) 10 to 50 parts by weight of a polyfunctional thiol compound; (d) 0.1 to 50 parts by weight of one or more photopolymerization initiators; and (e) 0.1 to 50 parts by weight of a silane coupling agent. Laminate for cover window.

12. In paragraph 1, The above silane coupling agent is in the form of an oligomer containing 2 to 20 structural units represented by the following chemical formula 2. Laminate for cover window: <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5.

13. In paragraph 1, The weight average molecular weight of the above silane coupling agent is 1,000 to 2,000. Laminate for cover window.

14. In paragraph 12, In the above chemical formula 2, -OR3 is selected from the group consisting of a hydroxyl group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a pentyloxy group, a hexyloxy group, and combinations thereof. Laminate for cover window.

15. In paragraph 1, The above silane coupling agent is represented by the following chemical formula 21. Laminate for cover window: <Chemical Formula 21> In the above chemical formula 21, R3 is an alkyl group having 1 to 20 carbon atoms, L3 is an alkylene group having 1 to 10 carbon atoms, m2 and n2 are each independently an integer from 1 to 10, and provided that n2 and m2 only mean the number contained in one molecule of the compound represented by the chemical formula 21, and the connection order of the n2 structural units and the m2 structural units is not limited and can be connected in a random order.

16. In paragraph 1, The modulus of the above acrylic coating layer is 10 MPa to 5000 MPa. Laminate for cover window.

17. In paragraph 1, The hardness of the above hard coating layer is 3H or higher. Laminate for cover window.

18. In paragraph 1, The thickness of the acrylic coating layer is 10 ㎛ to 600 ㎛, and the thickness of the hard coating layer is 10 ㎛ to 200 ㎛. Laminate for cover window.

19. In paragraph 1, The thickness ratio of the acrylic coating layer and the hard coating layer is 20:1 to 1:

4. Laminate for cover window.

20. Polysilsesquioxane; aliphatic urethane (meth)acrylate oligomer; and heterocyclic compound containing oxygen; The weight ratio of the aliphatic urethane (meth)acrylate oligomer and the oxygen-containing heterocyclic compound and the aliphatic urethane (meth)acrylate oligomer is 1:1.5 to 7. Composition for forming a hard coating layer for a cover window.

21. In paragraph 20, The above polysilsesquioxane comprises a structural unit represented by Chemical Formula 1-1 and a structural unit represented by Chemical Formula 1-2. Composition for forming a hard coating layer for a cover window: <Chemical Formula 1-1> <Chemical Formula 1-2> In the above chemical formulas 1-1 and 1-2, R1 is, each independently, a halogen group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an amino group, a (meth)acrylic group, a vinyl group, an epoxy group, a thiol group, a glycidyl ether-substituted alkyl group having 1 to 10 carbon atoms, or an alicyclic epoxy-substituted alkyl group having 1 to 10 carbon atoms, R2 is, each independently, hydrogen or a straight-chain or branched alkyl group having 1 to 10 carbon atoms.

22. A composition for forming an acrylic coating layer for a cover window, comprising a silane coupling agent in the form of an oligomer represented by the following chemical formula 2: <Chemical Formula 2> In the above chemical formula 2, R3 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, X is an alkyl group having 1 to 20 carbon atoms, an epoxy group, a mercapto group, an acrylate group, or an aryl group having 5 to 20 carbon atoms, L1 and L2 are each independently a single bond, an alkylene group having 1 to 30 carbon atoms, or a heteroalkylene group having 1 to 20 carbon atoms, b is an integer from 0 to 5.

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