Hard coat film and resin molding using the same

Abstract

To provide a hard coat film excellent in high surface hardness, scratch resistance, leveling (smoothness) and recoatability (recoatability).SOLUTION: A hard coat film includes: a base material layer including a thermoplastic resin; and a hard coat layer served as a cured coating layer on at least one surface of the base material layer. The hard coat layer including a fluoride containing leveling agent has a surface roughness of 10 nm or less; a fluorine atomic concentration F (80°) at an angle of 80°measured by angle-resolved XPS is 10 atomic% or less; and a fluorine atomic concentration F (30°) at an angle of 30 is 10 atomic% or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a hard-coated film including a substrate layer and a hard-coating layer, and a resin molded product using the hard-coated film. In particular, the present invention relates to a hard-coated film having high surface hardness, excellent scratch resistance, leveling property (smoothness), and recoatability (reapplicability). [Background technology]

[0002] In recent years, substrate films, particularly biaxially oriented polyester films, have been applied to various fields such as magnetic recording materials, packaging materials, electrical insulating materials, and optical display materials (e.g., anti-reflection films and films for touch panels) because of their excellent properties such as mechanical properties, dimensional stability, heat resistance, transparency, and electrical insulation.

[0003] The above-mentioned substrate films have come to be used as substitutes for glass products from the viewpoints of weight reduction, processability, etc., but since the surface of these substrate films has a drawback in that they are easily scratched, they have generally been used by providing a hard coat layer for the purpose of imparting scratch resistance, or by laminating a film provided with a hard coat layer. Furthermore, even in conventional glass products, plastic films are often laminated to prevent glass from scattering when the glass is broken, and it is widely and generally practiced to form a hard coat layer on the surface of the film.

[0004] However, in order to improve the smoothness of the coating film after curing, the conventional hard coat layer contains a leveling agent such as silicone oil or fluorinated polyolefin (see Patent Document 1) that significantly reduces the surface tension, so that although the leveling property (smoothness) is sufficient, the recoatability (reapplicability) is insufficient. That is, when such a leveling agent that reduces the surface tension is contained in the hard coat layer, the surface energy of the hard coat layer is reduced, so that when other composition layers according to the application, such as an antistatic layer, a high refractive index layer, or a low refractive index layer, are applied on the hard coat layer, coating defects such as coating repellency, coating unevenness, and coating streaks are often generated, and the recoatability is not fully satisfactory. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-267804 A DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0006] The present invention aims to solve at least one of the above-mentioned problems in the prior art, and in particular to provide a hard coat film having high surface hardness, excellent scratch resistance, leveling property (smoothness), and recoatability (reapplicability). [Means for solving the problem]

[0007] As a result of intensive research aimed at solving the above-mentioned problems, the present inventors have found that by incorporating a specific fluorine-containing leveling agent in the hard coat layer, it is possible to provide a hard coat film having excellent leveling properties (smoothness) and recoatability (reapplicability), and have thus completed the present invention.

[0008] That is, the present invention is as follows. <1> A hard coat film having a substrate layer containing a thermoplastic resin and a hard coat layer which is a cured coating layer on at least one surface of the substrate layer, The hard coat film is characterized in that the hard coat layer contains a fluorine-containing leveling agent, the surface roughness of the hard coat layer is 10 nm or less, the fluorine atomic concentration F(80°) at an angle of 80° is 10 atomic% or less, and the fluorine atomic concentration F(30°) at an angle of 30° is 10 atomic% or less, as measured by angle-resolved XPS. <2> The contact angle of propylene glycol monomethyl ether on the surface of the hard coat layer is 10° or less. <1> 2. The hard coat film according to claim 1, <3> The hard coat layer further contains a photopolymerization initiator, a urethane (meth)acrylate, and solid inorganic particles. <1> or <2> 2. The hard coat film according to claim 1, <4> The pencil hardness of the surface of the hard coat layer is H or more. <1> from <3> 1. The hard coat film according to claim 1, <5> The above-mentioned has a low refractive index layer on the surface of the hard coat layer, the low refractive index layer having a refractive index lower than the refractive index of the hard coat layer by 0.05 or more. <1> from <4> 1. The hard coat film according to claim 1, <6> The low refractive index layer contains a fluorine-containing leveling agent and a silicon-containing slip agent. <5> 2. The hard coat film according to claim 1, <7> The above-mentioned are used for insert molding applications. <1> from <6> 1. The hard coat film according to claim 1, <8> the above <1> from <7> 2. A resin molded article having a surface coated with the hard coat film according to claim 1. Effect of the Invention

[0009] According to the present invention, it is possible to provide a hard coat film having high surface hardness, excellent scratch resistance, and excellent leveling (smoothness) and recoatability. According to the present invention, the coatability of a functional material provided on the hard coat layer is improved, so that the hard coat film can be suitably used in applications having a hard coat function such as an anti-reflection film for a display and in which multiple layers are laminated. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will be described in detail below. Note that the present invention is not limited to the following embodiments, and can be modified and carried out as desired within the scope of the effects of the invention.

[0011] [Hard coat film] One embodiment of the present invention is a hard coat film having a substrate layer containing a thermoplastic resin and a hard coat layer, which is a cured coating layer, on at least one surface of the substrate layer. By providing the hard coat layer, the surface hardness and scratch resistance of the hard coat film are improved. Hereinafter, each layer member contained in the hard coat film, which is such a laminate, will be described.

[0012] [Hard coat layer] The hard coat layer in the present invention contains a fluorine-containing leveling agent, and the surface roughness of the hard coat layer is 10 nm or less, preferably 9.6 nm or less, and more preferably 8.0 nm or less. In the present invention, the surface roughness is a value measured by the method described in the examples below. In the hard coat layer of the present invention, the fluorine atomic concentration F(80°) at an angle of 80° measured by angle-resolved XPS is 10 atomic% or less, preferably 8 atomic% or less, and more preferably 5 atomic% or less. Meanwhile, the fluorine atomic concentration F(30°) at an angle of 30° measured by angle-resolved XPS is 10 atomic% or less, preferably 9 atomic% or less, and more preferably 7 atomic% or less. In the present invention, the fluorine atomic concentration F is a value measured by the method described in the examples below.

[0013] The present invention is characterized in that a fluorine-containing leveling agent is used in the hard coat layer for the purpose of lowering the surface tension of the coating film in order to reduce coating unevenness. "Leveling" refers to the property of paint flowing after application to form a flat, smooth coating. Good leveling is determined when there are few microscopic bumps on the surface of the coating, such as brush marks, yuzu skin (the texture of the surface of an orange), or ripples. In a hard coat film using a general fluorine-containing leveling agent, since the surface of the hard coat layer has high smoothness, fluorine atoms are segregated, making it difficult to achieve both high appearance and recoatability. Therefore, the present inventors have realized the provision of a hard coat film with high appearance and excellent recoatability (with less coating repelling) by using a fluorine-containing leveling agent that is not easily segregated on the surface of the hard coat layer, thereby eliminating the segregation of fluorine atoms on the surface.

[0014] The fluorine-containing leveling agent used in the hard coat layer in the present invention is not particularly limited as long as it can achieve the leveling property (smoothness) and recoatability (reapplicability) as described above. Preferred examples include Ftergent 602A (manufactured by Neos Corporation: a surfactant having a perfluoroalkenyl group, a UV-reactive group, and a lipophilic group (organic component)), Ftergent 218 (manufactured by Neos Corporation), Ftergent 683 (manufactured by Neos Corporation), and Megafac R-40 (manufactured by DIC Corporation). In the present invention, the content of the fluorine-containing leveling agent is preferably 0.01% by mass or more and 1% by mass or less, and more preferably 0.05% by mass or more and 0.5% by mass or less, when the content of the urethane (meth)acrylate that is preferably used as a coating material for forming a hard coat layer is taken as 100% by mass.

[0015] In one embodiment of the present invention, it is preferable to have a low refractive index layer and / or a high refractive index layer on the hard coat layer, as described below, but in a hard coat film having a laminate structure including a low refractive index layer, a high refractive index layer, and a hard coat layer, it is preferable that the hard coat layer is laminated between the substrate layer and the high refractive index layer. That is, it is preferable that these layers are laminated in the order of the substrate layer, the hard coat layer, the high refractive index layer, and the low refractive index layer. In a hard coat film having such a laminate structure, a high antireflection effect is achieved and the surface hardness, that is, the hardness of the surface opposite to the substrate layer, is improved.

[0016] The hard coat layer is preferably formed by a hard coat treatment performed on the surface of the base layer, etc. That is, it is preferable to laminate the hard coat layer by applying a hard coat material that can be cured by heat or active energy rays, and then curing the applied material. An example of a coating material that is cured using active energy rays is a resin composition consisting of a single or multiple monofunctional or polyfunctional acrylate monomers or oligomers, more preferably a resin composition containing a urethane (meth)acrylate oligomer, etc. In this specification, "(meth)acrylate" means acrylate and methacrylate. These resin compositions contain the above-mentioned fluorine-containing leveling agent as an essential component, and preferably further contain a photopolymerization initiator as a curing catalyst and solid inorganic particles. Examples of thermosetting resin coatings include polyorganosiloxane-based and crosslinked acrylic-based coatings. Some of these resin compositions, excluding fluorine-containing leveling agents, are commercially available as hard coat agents for acrylic resins or polycarbonate resins, and can be selected appropriately taking into account suitability for the coating line. In addition to organic solvents, these coating materials may contain various stabilizers such as ultraviolet absorbers, light stabilizers, and antioxidants, as well as defoamers, thickeners, antistatic agents, anti-fogging agents, and surfactants, if necessary.

[0017] An example of a hard coat coating material that is cured using active energy rays is one in which 1 to 10 parts by mass of a photopolymerization initiator is added to 100 parts by mass of a photopolymerizable resin composition obtained by mixing 40 to 95% by mass of a hexafunctional urethane acrylate oligomer and about 5 to 60% by mass of a (meth)acrylate such as 2-(2-vinyloxyethoxy)ethyl (meth)acrylate [2-(2-vinyloxyethoxy)ethyl acrylate: VEEA].

[0018] As the photopolymerization initiator, generally known ones can be used, specifically, benzoin, benzophenone, benzoin ethyl ether, benzoin isopropyl ether, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, azobisisobutyronitrile, benzoyl peroxide, etc.

[0019] The solid inorganic particles are not particularly limited as long as they can improve the scratch resistance of the hard coat layer, but nanosilica particles, nanoalumina particles, nanozirconia particles, glass particles, etc. can be preferably used, and nanosilica particles can be more preferably used. In the present invention, the content of the solid inorganic particles is preferably 0.5% by mass or more and 3% by mass or less, and more preferably 1.0% by mass or more and 2.0% by mass or less, when the content of the urethane (meth)acrylate that is preferably used as a coating material for forming a hard coat layer is taken as 100% by mass.

[0020] The refractive index of the hard coat layer is preferably approximately the same as that of the substrate layer. Specifically, the hard coat layer preferably has a refractive index in the range of 1.43 to 1.65. The refractive index of the hard coat layer is more preferably 1.47 to 1.60, and further preferably 1.49 to 1.57. The difference between the refractive index of the substrate layer and the refractive index of the hard coat layer is preferably 0.04 or less, more preferably 0.03 or less, and further preferably 0.02 or less. In order to make the refractive index of the hard coat layer closer to that of the substrate layer, a high refractive index member described later may be appropriately added to the hard coat coating material.

[0021] The thickness of the hard coat layer is not particularly limited, but is preferably 1 to 10 μm, more preferably 2 to 8 μm, and further preferably 2 to 6 μm.

[0022] When a second cured layer is formed on the first cured layer containing the above-mentioned fluorine-containing leveling agent for improving the surface condition, the leveling agent present on the surface of the first cured layer blocks the interface between the first cured layer and the second cured layer, and the bond connecting the first cured layer and the second cured layer is not formed, which may cause a problem of poor adhesion. In addition, if the wettability of the first cured layer is low, repelling may occur when the second cured layer is applied, and the second cured layer may not be formed. Therefore, it is necessary to select an appropriate leveling agent to solve these problems.

[0023] Furthermore, if the first cured layer is not completely cured, when the second cured layer is formed, the leveling agent may be extracted by the second cured layer forming liquid and bleed out onto the second cured layer, which may affect the performance of the surface of the second cured layer.

[0024] [Base material layer] The substrate layer included in the hard coat film contains a thermoplastic resin. The type of thermoplastic resin is not particularly limited, but various resins such as polycarbonate (PC) resin, acrylic resin such as polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), triacetyl cellulose (TAC), polyethylene naphthalate (PEN), polyimide (PI), cycloolefin copolymer (COC), norbornene-containing resin, polyethersulfone, cellophane, and aromatic polyamide are used. Of these options, the thermoplastic resin of the substrate layer preferably contains at least a polycarbonate resin.

[0025] The type of polycarbonate resin contained in the base layer is not particularly limited as long as it contains a -[OR-OCO]- unit (wherein R contains an aliphatic group, an aromatic group, or both an aliphatic group and an aromatic group, and further has a straight-chain structure or a branched structure) containing a carbonate bond in the molecular main chain, but polycarbonates having a bisphenol skeleton are preferred, and polycarbonates having a bisphenol A skeleton or a bisphenol C skeleton are particularly preferred. As the polycarbonate resin, a mixture or copolymer of bisphenol A and bisphenol C may be used. By using a bisphenol C-based polycarbonate resin, for example, a polycarbonate resin containing only bisphenol C, or a mixture or copolymer of bisphenol C and bisphenol A, the hardness of the base layer can be improved. The viscosity average molecular weight of the polycarbonate resin is preferably from 15,000 to 40,000, more preferably from 20,000 to 35,000, and further preferably from 22,500 to 25,000.

[0026] The acrylic resin contained in the base layer is not particularly limited, but may be, for example, a homopolymer of various (meth)acrylic acid esters such as polymethyl methacrylate (PMMA) or methyl methacrylate (MMA), or a copolymer of PMMA or MMA with one or more other monomers, or a mixture of a plurality of these resins. Examples of monomers include cyclic acid anhydride units, N-substituted maleimide units, aromatic vinyl compound units, and aliphatic vinyl compound units. Among these, (meth)acrylates containing a cyclic alkyl structure, which have low birefringence, low moisture absorption, and excellent heat resistance, are preferred. Examples of such (meth)acrylic resins include, but are not limited to, Acrypet (manufactured by Mitsubishi Rayon), Delpet (manufactured by Asahi Kasei Chemicals), and Parapet (manufactured by Kuraray). It is preferable to use a mixture containing a polycarbonate resin and the above-mentioned acrylic resin, since the hardness of the substrate layer, particularly the surface layer (layer on the hard coat layer side) of the substrate layer as a laminate, can be improved.

[0027] The substrate layer may also contain additives as components other than the thermoplastic resin. For example, at least one additive selected from the group consisting of a heat stabilizer, an antioxidant, a flame retardant, a flame retardant assistant, an ultraviolet absorber, a release agent, and a colorant. In addition, an antistatic agent, a fluorescent brightener, an antifogging agent, a flow improver, a plasticizer, a dispersant, an antibacterial agent, etc. may be added to the substrate layer.

[0028] The base layer preferably contains 80% by mass or more of thermoplastic resin, more preferably 90% by mass or more, and particularly preferably 95% by mass or more of thermoplastic resin, and the base layer preferably contains 50% by mass or more of polycarbonate resin, more preferably 70% by mass or more, and particularly preferably 75% by mass or more of polycarbonate resin, of the thermoplastic resin.

[0029] The substrate layer preferably has a refractive index in the range of 1.49 to 1.65, and more preferably has a refractive index of about 1.49 to 1.60.

[0030] The thickness of the substrate layer is not particularly limited, but is preferably 30 to 1000 μm (1 mm), more preferably 50 to 700 μm, and particularly preferably 100 to 500 μm. In addition, the hard coat film may have two or more substrate layers, and when a plurality of substrate layers are provided, the total thickness of the substrate layers is, for example, 100 to 1000 μm, and preferably about 200 to 500 μm.

[0031] Examples of the substrate layer including the above-mentioned multiple layers, that is, the substrate layer as a multi-layer laminate, include the following: A layer of the above-mentioned polycarbonate resin (PC), such as bisphenol A, is laminated with an acrylic resin layer such as the above-mentioned acrylic resin, such as poly(methyl meth)acrylate resin (PMMA: polymethyl acrylate and / or polymethyl methacrylate), as a surface layer (layer on the hard coat layer side); a layer of a resin made of a copolymer of the above-mentioned PMMA and one or more other monomers is laminated; a layer of a polycarbonate resin (PC) such as bisphenol A is laminated with a polycarbonate resin (PC) such as bisphenol C, etc. In a laminate in which a layer of a polycarbonate resin (PC) containing bisphenol A and a layer of a polycarbonate resin (PC) containing bisphenol C are laminated, for example, a layer of a polycarbonate resin containing bisphenol C is used as a surface layer. It is also preferable to use a surface layer having a high hardness, particularly a hardness higher than that of the other substrate layers.

[0032] The polycarbonate resin, which is a thermoplastic resin used in the laminate, is preferably the above-mentioned one, as well as the polycarbonate resin forming the single-layer substrate layer. For example, a mixture or copolymer of bisphenol A and bisphenol C may be used. By using a bisphenol C-based polycarbonate resin, for example, a polycarbonate resin containing only bisphenol C, or a mixture or copolymer of bisphenol C and bisphenol A, it is possible to improve the hardness of the surface layer (layer on the hard coat layer side) of the substrate layer, which is a laminate. In order to further improve the hardness, a mixture of the above-mentioned acrylic resin and a polycarbonate resin, for example, a bisphenol C-based polycarbonate resin, may be used.

[0033] [Low refractive index layer (anti-reflection layer)] As described above, in the present invention, it is preferable to have a low refractive index layer on the hard coat layer. The low refractive index layer preferably has a refractive index lower than the refractive index of the hard coat layer by 0.05 or more, more preferably has a refractive index lower by 0.07 or more, and particularly preferably has a refractive index lower by 0.08 to 0.12. If the low refractive index layer has a refractive index lower than the refractive index of the hard coat layer by 0.05 or more, sufficient anti-reflection performance can be obtained, which is preferable. The refractive index of the low refractive index layer is preferably in the range of 1.35 to 1.44, more preferably in the range of 1.38 to 1.42, and particularly preferably in the range of 1.39 to 1.41. If the refractive index is less than 1.35, it may be difficult to obtain sufficient hardness, while if the refractive index exceeds 1.44, it may be difficult to obtain sufficient antireflection performance.

[0034] The low refractive index layer has a thickness of preferably 70 to 130 nm, more preferably 80 to 120 nm, and particularly preferably 90 to 110 nm. If the low refractive index layer has a thickness of less than 70 nm, the wavelength region of light that can be prevented from being reflected may significantly shift to the low wavelength side, resulting in a deterioration in luminous reflectance, whereas if the thickness exceeds 130 nm, the wavelength region of light that can be prevented from being reflected may significantly shift to the high wavelength side, resulting in a deterioration in luminous reflectance. The low refractive index layer is preferably disposed on the outermost side of the hard coat film in order to suppress reflection from the hard coat film.

[0035] The low refractive index layer is formed by applying a coating liquid made of a composition for forming a low refractive index layer onto a hard coat layer, and then curing the coating liquid by irradiating ultraviolet light. The coating method, curing conditions, and dilution solvent for adjusting viscosity are not particularly limited and can be appropriately selected. The composition for forming a low refractive index layer can contain, for example, an ultraviolet curable resin, a fluorine-containing leveling agent, a silicon-containing slip agent, hollow silica fine particles, and a photopolymerization initiator.

[0036] <Ultraviolet curable resin> The type of ultraviolet curing resin forming the low refractive index layer is not particularly limited as long as it is a multifunctional (meth)acrylate.In this type of film, the resin forming the low refractive index layer is generally made of a reactive silicon compound such as γ-acryloxypropyltrimethoxysilane as a starting material in addition to the multifunctional (meth)acrylate, but from the viewpoint of achieving both productivity and hardness, a composition containing ultraviolet curing multifunctional (meth)acrylate as a main component is preferred.

[0037] The polyfunctional (meth)acrylate is not particularly limited, and examples thereof include (meth)acrylic derivatives of polyfunctional alcohols such as dipentaerythritol hexa(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,6-bis(3-(meth)acryloyloxy-2-hydroxypropyloxy)hexane, polyethylene glycol di(meth)acrylate, and polyurethane (meth)acrylate. In the present invention, polyurethane (meth)acrylate is particularly preferably used.

[0038] The polyfunctional (meth)acrylate may be a fluorine-containing monomer. The fluorine-containing monomer having a structure in which fluorine atoms are introduced into the molecule as a fluorinated methylene group or a fluorinated methine group is a monomer in which almost all of the fluorine atoms are introduced into the molecule as a fluorinated methylene group or a fluorinated methine group, and all known monomers can be used as long as the monomer is a polyfunctional monomer. That is, the monomer may be any monomer having two or more (polyfunctional) groups, or a mixture thereof. These fluorine-containing compounds can increase the strength and hardness of the cured film, and can improve the scratch resistance and wear resistance of the cured film surface. Among the fluorine-containing compounds, fluorine-containing polyfunctional (meth)acrylates are preferred because they can form a crosslinked structure and have high strength and hardness of the cured film.

[0039] <Fluorine-containing leveling agent> The fluorine-containing leveling agent contained in the low refractive index layer can smooth the layer and impart fingerprint wiping properties, thereby reducing the adhesion of fingerprints, which are lipids that adhere to the surface of the low refractive index layer when touched, and improving the ease with which fingerprints can be wiped off. Preferred examples of the fluorine-containing leveling agent contained in the low refractive index layer include (meth)acrylates containing a C2 to C7 perfluoroalkyl chain. Specific preferred examples include OPTOOL DAC-HP manufactured by Daikin Industries, Ltd. and MEGAFAC RS-75 and RS-78 manufactured by DIC Corporation.

[0040] The fluorine-containing leveling agent is preferably contained in the composition for forming the low refractive index layer in an amount of 1 to 20% by mass, more preferably 2.5 to 10% by mass. If the content is less than 1% by mass, it may not be possible to reduce the adhesion of fingerprints that are left when the surface of the low refractive index layer is touched. On the other hand, if the content exceeds 20% by mass, it may be difficult to obtain sufficient hardness and anti-reflection performance.

[0041] <Silicon-containing slip agent> The silicon-containing slip agent contained in the low refractive index layer can impart scratch resistance to fabric. A slip agent is an additive that maintains the physical stability of a material when the thermoplastic resin is heated and molded, preventing adhesion to metal surfaces, preventing adhesion between materials, improving the fluidity of the material, and reducing friction inside the material or with metal surfaces. The silicon-containing slip agent used in the present invention is preferably polydimethylsiloxane, more preferably polyether-modified polydimethylsiloxane having an acrylic group or polyester-modified polydimethylsiloxane having an acrylic group.Specifically, BYK-UV3500, BYK-UV3530, BYK-UV3570, etc. manufactured by BYK-Chemie Japan Co., Ltd. are preferably mentioned.

[0042] The silicon-containing slip agent is preferably contained in the composition for forming the low refractive index layer in an amount of 5 to 20% by mass, more preferably 10 to 17.5% by mass. If the content is less than 5% by mass, the fabric scratch resistance may be insufficient, whereas if it exceeds 20% by mass, it may be difficult to obtain sufficient hardness and anti-reflection performance.

[0043] In the present invention, the mass ratio of the silicon-containing slip agent and the fluorine-containing leveling agent contained in the low refractive index layer is preferably 9:1 to 5:5, and more preferably 7:1 to 5:5. If the mass ratio of the silicon-containing slip agent is more than 9:1, it may be difficult to obtain sufficient fingerprint wiping removability, while if the mass ratio of the fluorine-containing leveling agent is more than 5:5, it may be difficult to obtain sufficient cloth scratch resistance.

[0044] <Hollow Silica> The low refractive index layer in the present invention preferably contains hollow silica fine particles in order to reduce the refractive index of the low refractive index layer. The hollow silica fine particles are fine particles in which silica (silicon dioxide, SiO2) is formed into a nearly spherical shape and has a hollow part in its outer shell. The average particle diameter is 10 to 100 nm, the thickness of the outer shell is about 1 to 60 nm, the porosity of the hollow part is 40 to 45%, and the refractive index is a low refractive index of 1.20 to 1.29. Since the hollow part contains air with a refractive index of 1.0, it is possible to achieve a low refractive index and low reflectance for the cured film formed by curing the polyfunctional (meth)acrylate, and the scratch resistance and abrasion resistance of the cured film can be improved by the inorganic fine particles called silica fine particles. If the porosity of the hollow portion is less than 40%, the amount of air in the hollow portion will be so small that it may not be possible to achieve a low refractive index and low reflectance for the cured coating.On the other hand, if the porosity of the hollow portion exceeds 45%, the outer shell must be made thin to increase the porosity, which makes production difficult.

[0045] In addition, the hollow silica fine particles are preferably modified with a silane coupling agent as necessary. This allows the development of an excellent effect not found in conventional (non-modified) silica fine particles or hollow silica fine particles, namely, excellent compatibility with polyfunctional (meth)acrylate. Therefore, when the modified hollow silica fine particles are mixed with the polyfunctional (meth)acrylate, the aggregation of the modified hollow silica fine particles can be suppressed, and a cured film with no whitening and excellent transparency can be obtained. Furthermore, in the cured film, the polymerizable double bond of the silane coupling agent and the polymerizable double bond of the polyfunctional (meth)acrylate are copolymerized (chemically bonded) to form a strong cured film, so that the scratch resistance and wear resistance of the cured film can be dramatically improved.

[0046] The mass ratio of hollow silica particles and resin material (low refractive index coating material in Example 5 described later) contained in the low refractive index layer is preferably 20:80 to 60:40, more preferably 30:70 to 50:50. When the amount of hollow silica particles added is increased, the surface irregularities increase, and it may become difficult to achieve both fingerprint wiping ability and cloth scratch resistance. This is because fingerprints are easily embedded and particles are easily dropped off.

[0047] <Other ingredients> The low refractive index layer may contain metal fluoride fine particles or the like in order to reduce the refractive index of the low refractive index layer. When metal fluoride fine particles are used, examples of the metal fluoride contained in the particles include magnesium fluoride, aluminum fluoride, calcium fluoride, and lithium fluoride. The metal fluoride fine particles are preferably particulate, and the particle size (diameter) is not particularly limited, but is, for example, 10 to 200 nm, preferably 30 to 100 nm, more preferably 35 to 80 nm, and particularly preferably 45 to 65 nm. Moreover, in order to improve scratch resistance, metal oxide fine particles (such as silica) may be contained.

[0048] The composition for forming the low refractive index layer preferably contains a photoinitiator (photopolymerization initiator). The composition for forming the low refractive index layer may also contain a solvent.

[0049] [High refractive index layer (anti-reflection layer)] In the hard coat film of the present invention, in order to further reduce the reflectance, it is preferable to further have a high refractive index layer between the low refractive index layer and the hard coat layer. The high refractive index layer has a refractive index higher than that of the base layer, and has an anti-reflection function similar to the low refractive index layer. The high refractive index layer preferably contains a polymer of a resin material containing a fluorene-based diol, an isocyanate, and a urethane (meth)acrylate derived from a (meth)acrylate, and a (meth)acrylate. That is, the high refractive index layer is preferably a mixture of a urethane (meth)acrylate obtained by a dehydration condensation reaction of at least the three components of a fluorene-based diol, an isocyanate, and a (meth)acrylate, and a (meth)acrylate.

[0050] In the above resin material, the ratio of urethane (meth)acrylate to (meth)acrylate is preferably 99:1 to 50:50 (weight ratio), more preferably 95:5 to 70:30, further preferably 93:7 to 80:20, and particularly preferably 90:10 to 85:15.

[0051] The refractive index of the high refractive index layer is higher than that of the base layer, and the refractive index of the high refractive index layer is preferably 1.68 to 1.75, more preferably 1.69 to 1.74, and further preferably about 1.70 to 1.73. The difference between the refractive index of the high refractive index layer and the refractive index of the substrate layer is preferably at least 0.09, more preferably at least 0.12, even more preferably at least 0.15, and particularly preferably at least 0.17. The difference between the refractive index of the high refractive index layer and the refractive index of the substrate layer is, for example, in the range of 0.03 to 0.70, preferably 0.10 to 0.50, and even more preferably 0.15 to 0.26. In this way, by increasing the difference between the refractive index of the high refractive index layer and the refractive index of the substrate layer, the reflectance of the surface of the hard coat film on the high refractive index layer side can be increased.

[0052] <High refractive index materials> The high refractive index layer preferably contains a high refractive index member. The high refractive index member is added to increase the refractive index of the high refractive index layer. That is, by forming the high refractive index layer using the high refractive index member, the difference in refractive index between the high refractive index layer and the base layer can be increased, and the reflectance of the hard coat film can be further reduced. Examples of high refractive index members include titanium oxide, zirconium oxide (ZrO2), zinc oxide, alumina, colloidal alumina, lead titanate, red lead, yellow lead, zinc yellow, chromium oxide, ferric oxide, iron oxide black, copper oxide, magnesium oxide, magnesium hydroxide, strontium titanate, yttrium oxide, hafnium oxide, niobium oxide, tantalum oxide (Ta2O5), barium oxide, indium oxide, europium oxide, lanthanum oxide, zircon, tin oxide, and lead oxide, as well as composite oxides thereof such as lithium niobate, potassium niobate, lithium tantalate, and aluminum magnesium oxide (MgAl2O4). In addition, rare earth oxides can be used as high refractive index components, such as scandium oxide, yttrium oxide, lanthanum oxide, cerium oxide, praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, terbium oxide, dysprosium oxide, holmium oxide, erbium oxide, thulium oxide, ytterbium oxide, and lutetium oxide. Of the many options mentioned above, zirconia (zirconium oxide) is preferred for the high refractive index member.

[0053] The high refractive index member is preferably a particulate member. The particle size (diameter) of the particulate high refractive index member is not particularly limited, but is, for example, 1 to 100 nm, preferably 5 to 50 nm, more preferably 7.5 to 30 nm, and particularly preferably 10 to 25 nm. In addition, the high refractive index member, which is, for example, particulate, preferably includes a coating of an organic layer as a surface treatment layer that covers the outer surface of a metal oxide, etc. The coating of the organic layer improves the compatibility of the high refractive index member with the resin material that forms the high refractive index layer, and allows the high refractive index member to be firmly bonded to the resin material. The surface treatment layer is preferably a coating of an organic layer having an ultraviolet-reactive (curing) functional group introduced onto the surface.

[0054] The high refractive index layer preferably contains the above resin material and the high refractive index member in a weight ratio of 10:90 to 40:60, and the ratio of the above resin material and the high refractive index member is more preferably 15:85 to 35:65, and even more preferably 20:80 to 30:70.

[0055] The thickness of the high refractive index layer is not particularly limited, but is preferably 10 to 300 nm, more preferably 30 to 250 nm, further preferably 80 to 200 nm, and particularly preferably 130 to 170 nm.

[0056] <Other ingredients> The high refractive index layer or the above resin material forming the high refractive index layer preferably contains at least one of a photoinitiator and a leveling agent, and particularly preferably contains a photoinitiator. In addition, the above resin material may contain a solvent. Examples of the leveling agent include a fluorine-based leveling agent, an acrylic-based leveling agent, and a silicone-based leveling agent.

[0057] [Other layers] In the present invention, in addition to providing a low refractive index layer or a high refractive index layer by wet coating on the hard coat layer, the following functional layers may be provided: Examples include a metal layer or metal oxide layer by vapor deposition or sputtering, an adhesive layer or pressure-sensitive adhesive layer, a water- and oil-repellent layer, an antistatic layer, a visibility improving layer such as an AG pattern, and a decorative layer.

[0058] [Other properties of hard coat film] <Reflectance (luminous reflectance)> The luminous reflectance of the surface on the low refractive index layer side of the hard coat film, which is a preferred embodiment of the present invention, is preferably 3.0% or less, more preferably 1.6 to 2.8%, and particularly preferably 1.6 to 2.5%, as measured in accordance with JIS Z 8701. In the present invention, the luminous reflectance can be measured by the method described in the Examples below.

[0059] <Fabric abrasion resistance> The surface of the low refractive index layer side of the hard coat film, which is a preferred embodiment of the present invention, is preferably excellent in fabric abrasion resistance. 2 When the tape is run back and forth 100 times on the surface of the low refractive index layer side of the hard coat film, which is a preferred embodiment of the present invention, while applying a load of 100 times, it is preferable that no visible scratches are produced.

[0060] <Fingerprint wipe-off ability> The surface of the low refractive index layer of the hard coat film according to a preferred embodiment of the present invention preferably has excellent removability of fingerprints. Specifically, when the test described in the Examples below is carried out, it is preferable that fingerprints can be completely wiped off within 5 times.

[0061] [Method of manufacturing hard coat film] In the manufacture of the hard coat film, it is preferable that the substrate layer is formed first. In the manufacture of the substrate layer, a material such as a resin composition is processed into a layer (sheet) by a conventional method. For example, it is a method by extrusion molding or cast molding. An example of extrusion molding is a method in which pellets, flakes or powder of a resin composition is melted and kneaded in an extruder, then extruded from a T-die or the like, and the resulting semi-molten sheet is cooled and solidified while being pressed between rolls to form a sheet.

[0062] A resin material is applied to the outer surface of one or more substrate layers and cured to form a hard coat layer or a low refractive index layer. The resin material can be cured by photocuring, heat curing, or the like.

[0063] [Resin molded products] Another embodiment of the present invention is a resin molded product having the above-mentioned hard coat film on its surface. The resin molded product of the present invention can be obtained, for example, by molding a resin and integrating a hard coat film on the surface of the resin molded product using an insert molding fusion method. For example, a hard coat film can be held in a cavity in an injection mold and molten resin can be injected into the mold to obtain a resin molded product having a hard coat film integrated on its surface. Examples of resin molded articles include films attached to the surfaces of computer screens, television screens, plasma display panels, etc., and films used on the surfaces of polarizing plates used in liquid crystal display devices, sunglasses lenses, prescription eyeglass lenses, camera viewfinder lenses, various instrument covers, automobile glass, train glass, in-vehicle display panels, electronic device housings, etc. EXAMPLES

[0064] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and can be modified as desired without departing from the gist of the present invention.

[0065] [Example 1] The substrate used was a transparent substrate layer (DF02U manufactured by MGC Filsheet Co., Ltd.; total thickness 254 μm) in which a methacrylic resin layer was laminated on a polycarbonate resin layer made of 2,2-bis(4-hydroxyphenyl)propane (bisphenol A). The refractive index of this transparent substrate layer was measured by the method described below, and was found to be 1.498.

[0066] To 100% by mass of urethane acrylate UN-954 (manufactured by Negami Chemical Industries Co., Ltd.), 5% by mass of 1-hydroxy-cyclohexyl-phenyl-ketone (Omnirad-184 manufactured by IGM Resin) as a photopolymerization initiator, 2% by mass of nanosilica particles NanoBYK-3650 (manufactured by BYK Japan Co., Ltd.), and 0.1% by mass of Ftergent 602A (manufactured by Neos Co., Ltd.: a surfactant having a perfluoroalkenyl group, a UV-reactive group, and a lipophilic group (organic component)) as a fluorine-containing leveling agent were added, and then a solvent (propylene glycol monomethyl ether) was added to adjust the concentration so that the solid content was 25% by mass, to prepare hard coat paint A-1.

[0067] To form a hard coat layer, the above-mentioned hard coat paint A-1 was applied onto the transparent substrate layer using a bar coater so that the dry film thickness was 3 μm, and the coating was dried for 2 minutes in a drying oven at 80° C. Furthermore, the coating was irradiated with an ultraviolet ray with an integrated light dose of 200 mJ / cm 2 2 A hard coat film B-1 was obtained by irradiating with ultraviolet light so that the refractive index of the hard coat layer of the obtained hard coat film B-1 was measured by the method described below, and the refractive index was found to be 1.501.

[0068] [Example 2] A hard coat film B-2 was obtained in the same manner as in Example 1, except that a hard coat coating material A-2 was used in which the fluorine-containing leveling agent in the hard coat coating material A-1 was changed to Futergent 218 (manufactured by Neos Corporation).

[0069] [Example 3] A hard coat film B-3 was obtained in the same manner as in Example 1, except that the urethane acrylate in the hard coat paint A-1 was changed to KRM8296 (manufactured by Daicel-Allnex Corporation) and a hard coat paint A-3 was used without adding the nanosilica particles NanoBYK-3650.

[0070] [Example 4] A hard coat film B-4 was obtained in the same manner as in Example 1, except that the urethane acrylate in the hard coat paint A-1 was changed to EBECRYL8402 (manufactured by Daicel-Allnex Corporation) and a hard coat paint A-4 was used that did not contain the nanosilica particles NanoBYK-3650.

[0071] [Comparative Example 1] A hard coat film B-5 was obtained in the same manner as in Example 1, except that a hard coat coating material A-5 was used in which the fluorine-containing leveling agent in the hard coat coating material A-1 was changed to Futergent 681 (manufactured by Neos Corporation).

[0072] [Comparative Example 2] A hard coat film B-6 was obtained in the same manner as in Example 1, except that a hard coat coating material A-6 was used in which the fluorine-containing leveling agent in the hard coat coating material A-1 was replaced with Megafac RS-75 (manufactured by DIC Corporation: having a perfluoroalkyl group, a UV-reactive group, and a lipophilic group (organic component)).

[0073] [Comparative Example 3] A hard coat film B-7 was obtained in the same manner as in Example 1, except that a hard coat coating material A-7 was used in which the fluorine-containing leveling agent in the hard coat coating material A-1 was changed to Megafac RS-56 (manufactured by DIC Corporation).

[0074] [Comparative Example 4] A hard coat film B-8 was obtained in the same manner as in Example 1, except that a hard coat paint A-8 was used in which the urethane acrylate in the hard coat paint A-1 was changed to KRM8296 (manufactured by Daicel-Allnex Corporation), the nanosilica particles NanoBYK-3650 were not added, and the fluorine-containing leveling agent was changed to Megafac RS-75 (manufactured by DIC Corporation).

[0075] [Comparative Example 5] A hard coat film B-9 was obtained in the same manner as in Example 1, except that a hard coat paint A-9 was used in which the urethane acrylate in the hard coat paint A-1 was changed to EBECRYL8402 (manufactured by Daicel-Allnex Co., Ltd.), the nanosilica particles NanoBYK-3650 were not added, and the fluorine-containing leveling agent was changed to Megafac RS-75 (manufactured by DIC Corporation).

[0076] The hard coat films thus produced in Examples 1 to 4 and Comparative Examples 1 to 5 were measured as follows. <Refractive index> The refractive index (nD) was measured at 20° C. using an Abbe refractometer (model: NAR-3T) manufactured by Atago Co., Ltd., with the D line at a wavelength of 589 nm. For solutions containing a solvent, the refractive index was measured while the solvent was still present, and the refractive index of the solution without the solvent was calculated from the measured value and the dilution rate of the solvent.

[0077] <Surface roughness> The surface roughness of the hard coat film was measured under the following conditions using a scanning white light interference microscope VS1330 manufactured by Hitachi High-Tech Corporation in the multiple field of view mode. [Optical conditions] Camera: Sony XCL-C30 1 / 3" Lens: Dual-beam interference objective lens (5x) [Measurement conditions] Mode: Wave Measurement range (1 field of view): 935μm x 701μm Field of view: 5×5 ·Overlap rate: 20% Measurement range (full field of view): 3928μm x 2946μm

[0078] <Angle-resolved XPS (X-ray photoelectron spectroscopy)> Measurements were performed under the following conditions using a scanning X-ray photoelectron spectrometer PHI5000 manufactured by ULVAC-PHI, Inc. X-ray source: Al Kα, monochrome 1486.6eV, 50W ·Analysis area 1.0×0.2mm 2 Measurement angle: 30°, 80° Pass energy 23eV (C1s, O1s, F1s) 187eV (N1s, Si2p) Photoelectron capture angle Narrow mode (±5°) The surface atomic concentration was calculated from the peak area obtained using the relative sensitivity factor provided by Phi Corp. Note that, since the concentrations of N1s and Si2p were low, high-sensitivity measurements were performed by lowering the pass energy.

[0079] <Contact angle (propylene glycol monomethyl ether)> Using an automatic contact angle meter DMo-601 (manufactured by Kyowa Interface Science Co., Ltd.), contact angles were measured using a test liquid of propylene glycol monomethyl ether under the following conditions. Volume: 2.0μL ·Analysis method: Θ / 2 method

[0080] <Recoatability (suitability for topcoating)> A paint prepared by diluting urethane acrylate UN-954 (manufactured by Negami Chemical Industries, Ltd.) with propylene glycol monomethyl ether (PGME) to a solid content concentration of 25% by mass was applied onto the hard coat layer of each hard coat film using a bar coater so that the dry film thickness was 1 μm, and the film was dried for 2 minutes in a drying oven at 80°C. The recoatability was evaluated in three stages according to the number of repellings that occurred. The evaluation criteria are as follows, and products rated ◯ were judged to have passed the recoatability. 〇:0, 1 piece △:2~5 pieces ×:6 or more

[0081] <Smoothness> In order to eliminate the influence of backside reflection, the surface of the hard-coated film on the substrate layer side (either surface in the case of a double-sided hard-coated film) was colored with black magic marker. The hard-coated film was placed with the uncolored side facing up and visually observed from above under a three-wavelength fluorescent lamp to evaluate the smoothness. ◯ (Good smoothness): Almost no distortion or unevenness is visible on the surface. △ (slightly good smoothness): There is some distortion or unevenness on the surface. × (poor smoothness): Distortion or unevenness is observed on the surface.

[0082] <Pencil hardness> The pencil hardness of the surface of the hard coat layer of the hard coat film was evaluated in accordance with JIS K5600-5-4, using a load of 500 g. [Table 1]

[0083] [Example 5] A curable low refractive index coating material was prepared as follows. First, dry air was introduced into a five-neck flask equipped with a stirrer, a thermometer, a cooler, a monomer dropping funnel, and a dry air inlet tube to dry the inside of the system. Then, 58.9 parts by mass of 2,2,3,3-tetrafluoro-1,4 butanediol (C4DIOL manufactured by Exfluor Research Corporation), 279.8 parts by mass of pentaerythritol triacrylate, 0.5 parts by mass of dibutyltin laurate as a polymerization catalyst, and 500 parts by mass of methyl ethyl ketone as a solvent were added to the five-neck flask and heated to 60°C. After that, 161.3 parts by mass of isophorone diisocyanate were added and reacted at 60 to 70°C. It was confirmed by infrared absorption spectroscopy that the isocyanate residue in the reactant had been consumed, and the reaction was terminated to obtain a hexafunctional urethane acrylate oligomer. Furthermore, 2-(2-vinyloxyethoxy)ethyl acrylate (VEEA) was mixed with the urethane acrylate oligomer (urethane acrylate liquid) at a ratio of urethane acrylate liquid / VEEA=90 / 10 (mass %).

[0084] Hollow silica (JGC Catalysts and Chemicals Sururia 4320) was added to the low refractive index paint thus obtained (liquid component of the resin material) and mixed at a ratio of hollow silica / resin material = 50 / 50 (mass%). Furthermore, 4 mass% of 1-hydroxy-cyclohexyl-phenyl-ketone (IGM Resin's Omnirad-184) was added as a photoinitiator, 10 mass% of BYK-UV3500 (BYK Chemie) as a silicon-containing slip agent, and 10 mass% of RS-78 (DIC) as a fluorine-containing leveling agent were added and dissolved, and a solvent (propylene glycol monomethyl ether) was added to adjust the concentration so that the solid concentration was 3 mass%. The obtained low refractive index paint was named low refractive index paint C-1.

[0085] The low refractive index paint C-1 was applied onto the hard coat layer of the hard coat film B-1 described in Example 1 so that the dry coating film had a thickness of 100 nm, and dried at 80° C. for 2 minutes. Further, the coating was cured with an ultraviolet curing device with an integrated ultraviolet light amount of 400 mJ / cm 2 . 2 Thus, a low refractive index layer having a thickness of 100 nm was formed on the outer surface of the hard coat film B-1, and an antireflection film D-1 was produced.

[0086] [Example 6] An antireflection film D-2 was produced in the same manner as in Example 5, except that the hard coat film B-2 described in Example 2 was used.

[0087] The thus-prepared anti-reflection films of Examples 5 and 6 were measured as follows. <Refractive index> The refractive index (nD) was measured at 20°C using an Abbe refractometer (model: NAR-3T) manufactured by Atago Co., Ltd., using the D line with a wavelength of 589 nm. For the solution containing the solvent, the refractive index was measured while the solvent was still present, and the refractive index of the solution without the solvent was calculated from the measured value and the dilution rate of the solvent. As a result, the refractive index of the low refractive index layer in the anti-reflection films D-1 and D-2 was 1.390 and 1.390, respectively.

[0088] <Reflectance (luminous reflectance)> The anti-reflection film was measured according to JIS Z 8701 using SD7000 manufactured by Nippon Denshoku Industries Co., Ltd. In order to prevent reflection from the back surface (substrate layer side) of the film of each example, the surface opposite the low refractive index layer was sprayed with black paint and dried before measurement. As a result, both of the anti-reflection films D-1 and D-2 had a reflection ratio of 1.7%, and it was confirmed that they exhibited sufficient anti-reflection performance.

[0089] <Fabric abrasion resistance> Medical gauze Medigauze 4 folds (manufactured by Osaki Medical Co., Ltd.) 100g / cm 2 The film was run back and forth 100 times on the surface of the low refractive index layer of each example film under a load of 10 ... 〇: No scratches ×: One or more scratches As a result, it was confirmed that neither of the antireflection films D-1 and D-2 had any scratches.

[0090] <Fingerprint wipe-off ability> After dropping artificial fingerprint liquid (oleic acid) onto the surface of the sample, the artificial fingerprint liquid was thinly spread to a diameter of approximately 11 mm using a silicon pad. The artificial fingerprint liquid was passed over the sample with a 3M Japan Scotch-Brite No. 5000 cloth under a load of 500 g. The above test was repeated until the liquid was wiped off. If the liquid was completely wiped off after five tries, the sample was rated as having good fingerprint wiping properties, and if it was wiped off six or more times, the sample was rated as having poor fingerprint wiping properties. As a result, it was confirmed that the antireflection films D-1 and D-2 could both be wiped off with three tries, and thus had good fingerprint wiping properties.

Claims

1. A hard coat film having a substrate layer containing a thermoplastic resin and a hard coat layer which is a cured coating layer on at least one surface of the substrate layer, the hard coat film, wherein the hard coat layer contains a fluorine-containing leveling agent, the surface roughness of the hard coat layer is 10 nm or less, and the fluorine atomic concentration F(80°) at an angle of 80° is 10 atomic% or less, and the fluorine atomic concentration F(30°) at an angle of 30° is 10 atomic% or less, as measured by angle-resolved XPS.

2. 2. The hard coat film according to claim 1, wherein the contact angle of propylene glycol monomethyl ether on the surface of the hard coat layer is 10[deg.] or less.

3. 10. The hardcoat film of claim 1, wherein the hardcoat layer further comprises a photoinitiator, a urethane (meth)acrylate, and solid inorganic particles.

4. 2. The hard coat film according to claim 1, wherein the pencil hardness of the surface of the hard coat layer is H or more.

5. 2. The hard coat film according to claim 1, further comprising a low refractive index layer on a surface of the hard coat layer, the low refractive index layer having a refractive index lower than the refractive index of the hard coat layer by 0.05 or more.

6. 6. The hard coat film of claim 5, wherein the low refractive index layer contains a fluorine-containing leveling agent and a silicon-containing slip agent.

7. The hard coat film according to claim 1 , which is used for insert molding applications.

8. A resin molded product having a surface thereof coated with the hard coat film according to claim 1 .