Hard coat film

Abstract

To provide a hard coat film having excellent adhesion to the other hard coat layer even when another hard coat layer is laminated.SOLUTION: There is provided a hard coat film 1 comprising a base material film 11 and a hard coat layer 12 provided on at least one surface of the base material film 11, wherein the silicon atom ratio measured by X-ray photoelectron spectroscopy on the surface opposite to the base material film 11 of the hard coat layer 12 is 1 atomic % or more and 14 atomic % or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a hard coat film. [Background technology]

[0002] In recent years, touch panels that serve as both a display device and an input means have become increasingly popular in various electronic devices. To prevent scratches, the surface of these touch panels is often provided with a hard coat film, which is a base film having a hard coat layer formed thereon.

[0003] In the hard coat film as described above, a plurality of hard coat layers may be provided depending on a predetermined purpose. For example, Patent Document 1 discloses an antistatic hard coat film in which an antistatic hard coat layer is laminated on at least one surface of a plastic film substrate, the antistatic hard coat layer being composed of metal oxide particles (A) having an average primary particle size of 1 to 10 nm and metal oxide particles (B) having an average primary particle size of 20 to 50 nm, with the ratio A / B being 10 / 90 to 30 / 70, and the antistatic hard coat layer is the outermost layer, and another hard coat layer is provided as an underlying layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-130667 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when a plurality of hard coat layers are provided, the adhesion between the hard coat layers is low, and the upper hard coat layer may peel off.

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a hard coat film that has excellent adhesion to another hard coat layer even when another hard coat layer is further laminated thereon. [Means for solving the problem]

[0007] In order to achieve the above object, first, the present invention provides a hard coat film comprising a substrate film and a hard coat layer provided on at least one surface of the substrate film, wherein the silicon atomic ratio of the hard coat layer on the surface opposite to the substrate film, as measured by X-ray photoelectron spectroscopy, is 1 atomic % or more and 14 atomic % or less (Invention 1).

[0008] In the above invention (Invention 1), although the hard coat layer (first hard coat layer) contains a component derived from silicon atoms, the silicon atom ratio on the surface of the first hard coat layer is in the relatively low range as described above, so that even when another hard coat layer (second hard coat layer) is laminated on the first hard coat layer, the adhesion between the first hard coat layer and the second hard coat layer is excellent.

[0009] In the above invention (Invention 1), it is preferable that the hard coat layer contains a dispersant (Invention 2).

[0010] In the above invention (Invention 2), the content of the dispersant in the hard coat layer is preferably 0.5% by mass or more and 35% by mass or less (Invention 3).

[0011] In the above inventions (Inventions 2 and 3), the dispersant is preferably an acrylic resin having a reactive group (Invention 4).

[0012] In the above inventions (Inventions 1 to 4), it is preferable that the hard coat layer is formed by curing a composition for hard coat layer containing an organic-inorganic hybrid resin (Invention 5).

[0013] In the above inventions (Inventions 1 to 5), it is preferable that the hard coat layer contains a silicone filler (Invention 6).

[0014] In the above inventions (Inventions 1 to 6), it is preferable that the hard coat layer contains a leveling agent (Invention 7).

[0015] In the above inventions (Inventions 1 to 7), the base film is preferably a polyethylene terephthalate film, a polycarbonate film, a triacetyl cellulose film, or a norbornene-based polymer film (Invention 8).

[0016] In the above inventions (Inventions 1 to 8), the thickness of the hard coat layer is preferably 0.1 μm or more and 20 μm or less (Invention 9).

[0017] In the above inventions (inventions 1 to 9), it is preferable that the optical element is for optical use (invention 10). [Effects of the Invention]

[0018] The hard coat film according to the present invention has excellent adhesion to another hard coat layer even when the hard coat film is further laminated with another hard coat layer. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a cross-sectional view of a hard coat film according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described. 1 is a cross-sectional view of a hard coat film according to one embodiment of the present invention. The hard coat film 1 according to this embodiment includes a substrate film 11 and a hard coat layer 12 provided on one surface of the substrate film 11.

[0021] In the hard coat film 1 according to the embodiment, the silicon atomic ratio (hereinafter sometimes referred to as the "surface silicon atomic ratio") of the surface of the hard coat layer 12 opposite the substrate film 11, as measured by X-ray photoelectron spectroscopy, is 1 atomic % or more and 14 atomic % or less. Even though the hard coat layer 12 contains components derived from silicon atoms, the silicon atomic ratio of the surface of the hard coat layer 12 is in the relatively low range described above. Therefore, even when another hard coat layer is laminated on the hard coat layer 12, the adhesion between the hard coat layer 12 and the other hard coat layer is excellent. Substances containing silicon atoms, such as silica and silicone, have the effect of lowering surface free energy. By satisfying the above physical properties, the proportion of silicon-containing substances on the surface of the hard coat layer 12 is reduced, resulting in improved adhesion between the hard coat layer 12 and the other hard coat layer, as described above. The specific method of X-ray photoelectron spectroscopy described herein is as shown in the test examples described below.

[0022] From the viewpoint of adhesion between the hard coat layer 12 and another hard coat layer, the surface silicon atomic ratio is preferably 13.6 atomic % or less, more preferably 13.2 atomic % or less, particularly preferably 13 atomic % or less, and even more preferably 12.8 atomic % or less. On the other hand, from the viewpoint of obtaining the effects of components derived from silicon atoms (particularly silica fine particles) (for example, improvements in weather resistance, hardness, solvent resistance, clarity, etc.), the surface silicon atomic ratio is preferably 3 atomic % or more, more preferably 5 atomic % or more, particularly preferably 7 atomic % or more, and even more preferably 9 atomic % or more.

[0023] 1. Each element 1-1.Hard coat layer The hard coat layer 12 of the hard coat film 1 according to this embodiment imparts high surface hardness and excellent scratch resistance to the hard coat film 1. This hard coat layer 12 is not particularly limited as long as the surface silicon atomic ratio is within the above-mentioned range.

[0024] The hard coat layer 12 in this embodiment is preferably obtained by curing a composition for hard coat layer containing a curable component (hereinafter, sometimes referred to as "composition C for hard coat layer").

[0025] (1) Each ingredient (1-1) Curable component (A) The curable component (A) is a component that is cured by a trigger such as active energy rays or heat, and examples thereof include an active energy ray-curable component and a thermosetting component. In the hard coat layer 12 of this embodiment, it is preferable to use an active energy ray-curable component from the viewpoint of adhesion to another hard coat layer. The active energy ray-curable component is one that is cured by irradiation with active energy rays, which will be described later.

[0026] Preferred examples of the active energy ray-curable component include multifunctional (meth)acrylate monomers, (meth)acrylate prepolymers, and active energy ray-curable polymers. Among these, multifunctional (meth)acrylate monomers or (meth)acrylate prepolymers are more preferred. The multifunctional (meth)acrylate monomers and (meth)acrylate prepolymers may be used alone or in combination. In this specification, the term "(meth)acrylate" refers to both acrylate and methacrylate. The same applies to other similar terms.

[0027] Examples of polyfunctional (meth)acrylate monomers include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphate di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, Examples of suitable (meth)acrylates include polyfunctional (meth)acrylates such as acrylate, dipentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, propionic acid-modified dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene oxide-modified dipentaerythritol hexa(meth)acrylate, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. These may be used alone or in combination of two or more.

[0028] Examples of the (meth)acrylate prepolymer include polyester acrylate, epoxy acrylate, urethane acrylate, and polyol acrylate prepolymers.

[0029] The polyester acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends, obtained by condensation of a polycarboxylic acid and a polyhydric alcohol, with (meth)acrylic acid, or by esterifying the terminal hydroxyl groups of an oligomer obtained by adding an alkylene oxide to a polycarboxylic acid, with (meth)acrylic acid.

[0030] Epoxy acrylate prepolymers can be obtained, for example, by reacting (meth)acrylic acid with the oxirane ring of a relatively low molecular weight bisphenol epoxy resin or novolac epoxy resin to esterify it.

[0031] The urethane acrylate prepolymer can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or polyester polyol with a polyisocyanate with (meth)acrylic acid.

[0032] The polyol acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl groups of a polyether polyol with (meth)acrylic acid.

[0033] The above prepolymers may be used singly or in combination of two or more.

[0034] It is also preferable to use an organic-inorganic hybrid resin as the active energy ray-curable component. A preferred example of the organic-inorganic hybrid resin is a substance obtained by bonding an organic compound having a polymerizable unsaturated group to inorganic fine particles via a silane coupling agent or the like. This organic-inorganic hybrid resin is also preferably in the form of an organosol (colloid) (e.g., silica sol), and may be used by mixing with an active energy ray-curable component such as the above-mentioned polyfunctional (meth)acrylate monomer. The inorganic fine particles contained in the organic-inorganic hybrid resin do not correspond to a filler, which will be described later, but function as a binder, and can improve the hardness of the hard coat layer 12 to be formed.

[0035] The organic-inorganic hybrid resin is preferably one in which (meth)acryloyl groups or silanol groups are bonded to inorganic fine particles to further strengthen the hard coat layer 12 after curing. Examples of the inorganic fine particles include silica fine particles, titanium oxide fine particles, and zirconia (zirconium dioxide) fine particles, with silica fine particles being particularly preferred.

[0036] The inorganic fine particles, particularly silica fine particles, preferably have an average particle size of 1 to 1,000 nm, more preferably 5 to 700 nm, particularly preferably 10 to 400 nm, even more preferably 20 to 200 nm, and most preferably 30 to 100 nm. This ensures good strength of the hard coat layer 12 after curing. The average particle size of the inorganic fine particles is measured by a centrifugal sedimentation light transmission method.

[0037] (1-2) Dispersant (B) The composition C for hard coat layer preferably contains a dispersant (B). By selecting the type and amount of the dispersant (B), the dispersibility of the silica fine particles can be suitably controlled, which makes it easier to satisfy the above-mentioned surface silicon atom ratio.

[0038] As the dispersant (B), for example, a compound having one or more polar groups selected from the group consisting of a carboxyl group, a hydroxyl group, a sulfo group, a primary amino group, a secondary amino group, a tertiary amino group, an amide group, a quaternary ammonium base, a pyridium base, a sulfonium base, and a phosphonium base in the molecule is preferred, and a compound having one or more polar groups selected from the group consisting of a carboxyl group and a hydroxyl group is particularly preferred. One or more of the above polar groups may be introduced into the molecule. When the compound serving as the dispersant (B) has multiple polar groups, the basic skeleton of the compound is preferably composed of an ester chain, a vinyl chain, an acrylic chain, an ether chain, a urethane chain, or the like. Specifically, acrylic resins, urethane resins, polyester resins, and alkyd resins are preferred, with acrylic resins, urethane resins, and polyester resins being particularly preferred, and acrylic resins being even more preferred. The polar groups may be arranged randomly in the molecule, but are preferably arranged in the side chain. The dispersants (B) may be used singly or in combination of two or more.

[0039] Among the above, as the dispersant (B), an acrylic resin having at least a carboxy group is preferred, and an acrylic resin having a carboxy group on the side chain is particularly preferred, and an acrylic resin having a carboxy group and a hydroxyl group on the side chain is even more preferred. A preferred commercially available dispersant (B) is, for example, "FLOWLEN G700" manufactured by Kyoeisha Chemical Co., Ltd. The above dispersant (B) makes it easier to satisfy the above-mentioned surface silicon atom ratio.

[0040] The content of the dispersant (B) in the composition C for hard coat layer is preferably 0.5 to 35 parts by mass, more preferably 1 to 30 parts by mass, particularly preferably 2 to 25 parts by mass, even more preferably 3 to 20 parts by mass, and especially preferably 4 to 15 parts by mass, relative to 100 parts by mass of the curable component (A). This makes it easier to satisfy the above-mentioned surface silicon atom ratio.

[0041] (1-3) Filler (C) The composition C for a hard coat layer also preferably contains a filler (C), which can impart various properties to the hard coat layer 12. For example, the hardness of the hard coat layer 12 can be increased, or the hard coat layer 12 can be provided with low reflectivity, antiglare properties, glare suppression properties, etc., or the refractive index can be adjusted, or the haze can be adjusted, or the hard coat layer 12 can be colored.

[0042] The filler (C) may be an organic filler, an inorganic filler, or a resin filler having both inorganic and organic properties. From the viewpoint of easily achieving good dispersibility, coating stability, desired optical properties, good appearance, etc., the filler (C) is preferably an organic filler or a resin filler having both inorganic and organic properties, and from the viewpoint of low reflectivity, antiglare properties, or glare suppression properties, a resin filler having both inorganic and organic properties is preferred.

[0043] Examples of organic fillers include acrylic resin fillers (e.g., polymethyl methacrylate fillers), silicone fillers, melamine resin fillers, acrylic-styrene copolymer fillers, polycarbonate fillers, polyethylene fillers, polystyrene fillers, and benzoguanamine resin fillers. These resins may be crosslinked. Among the above, acrylic resin fillers and silicone fillers are preferred. In particular, polymethyl methacrylate fillers are preferred as acrylic resin fillers, and crosslinked polymethyl methacrylate fillers are more preferred.

[0044] Examples of inorganic fillers include fillers made of silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide, and the like.

[0045] As a resin filler having both inorganic and organic properties, a silicone filler (for example, the Tospearl series manufactured by Momentive Performance Materials Japan) is particularly preferred.

[0046] The filler (C) may be used singly or in combination of two or more kinds.

[0047] The filler (C) may be surface-modified as desired. The shape of the filler may be regular, such as spherical, or irregular, but from the viewpoint of low reflectivity, antiglare properties, and glare suppression, regular shapes are preferred, and spherical shapes are particularly preferred.

[0048] The average particle size of the filler (C) is preferably 0.5 to 20 μm, more preferably 1 to 10 μm, particularly preferably 2 to 8 μm, even more preferably 3 to 6 μm, and most preferably 4 to 5 μm. When the filler (C) is a silicone filler, having the above average particle size makes it easier to satisfy the above-mentioned surface silicon atom ratio. Furthermore, having the average particle size within the above range makes it easier to obtain optical properties such as low reflectivity, anti-glare properties, and glare suppression. The average particle size of the filler (C) is determined by measuring the primary particle size using laser diffraction measurement.

[0049] The refractive index of the filler (C) is preferably 1.2 to 1.6, more preferably 1.3 to 1.55, particularly preferably 1.4 to 1.5, and even more preferably 1.42 to 1.45, which makes it easier to obtain optical properties such as low reflectivity, antiglare properties, and glare suppression properties.

[0050] When the composition for hard coat layer C contains a filler (C), the content of the filler (C) is preferably 0.1 to 30 parts by mass, more preferably 0.3 to 20 parts by mass, particularly preferably 0.6 to 10 parts by mass, even more preferably 0.8 to 6 parts by mass, and even more preferably 0.9 to 2 parts by mass, per 100 parts by mass of the curable component (A). When the filler (C) is a silicone filler, the above content makes it easier to satisfy the above-mentioned surface silicon atom ratio. Furthermore, when the content of the filler (C) is within the above range, optical properties such as low reflectivity, antiglare properties, and glare suppression are easily obtained.

[0051] (1-4) Leveling agent (D) The composition C for hard coat layer preferably contains a leveling agent (D), which makes it easier to satisfy the above-mentioned surface silicon atomic ratio and improves the uniformity of the film thickness of the hard coat layer 12.

[0052] Examples of the leveling agent (D) are not particularly limited, and include, for example, fluorine-based leveling agents, silicone-based leveling agents, acrylic-based leveling agents, vinyl-based leveling agents, etc. Among these, fluorine-based leveling agents are preferred from the viewpoint of ease of satisfying the above-mentioned surface silicon atom ratio. The leveling agents may be used alone or in combination of two or more.

[0053] The fluorine-based leveling agent is preferably a compound having a perfluoroalkyl group or a fluorinated alkenyl group in the main chain or side chain. Examples of commercially available fluorine-based leveling agents include "Ftergent 602A" and "Ftergent 650A" manufactured by Neos Corporation, "BYK-340" manufactured by BYK Japan, "Megafac RS-75" manufactured by DIC Corporation, and "V-8FM" manufactured by Osaka Organic Chemical Industry Co., Ltd.

[0054] When the hard coat layer composition C contains a leveling agent (D), the content of the leveling agent (D) is preferably 0.001 to 1 part by mass, more preferably 0.01 to 0.7 parts by mass, particularly preferably 0.02 to 0.4 parts by mass, even more preferably 0.05 to 0.2 parts by mass, and of these, preferably 0.07 to 0.1 parts by mass, relative to 100 parts by mass of the curable component (A). This makes it easier to satisfy the above-mentioned surface silicon atom ratio, and the hard coat layer 12 is free of streak-like defects and unevenness, thereby improving the uniformity of the film thickness.

[0055] (1-5) Other ingredients The composition C for a hard coat layer in this embodiment may contain various additives in addition to the above components, such as a photopolymerization initiator, an ultraviolet absorber, a light stabilizer, an antifouling agent, an antioxidant, an antistatic agent, a silane coupling agent, an antiaging agent, a thermal polymerization inhibitor, a colorant, a surfactant, a storage stabilizer, a plasticizer, a lubricant, and an antifoaming agent.

[0056] (1-5-1) Photopolymerization initiator When the curable component (A) is an active energy ray-curable component and ultraviolet light is used for curing, the composition for hard coat layer C preferably contains a photopolymerization initiator, which allows the active energy ray-curable component to be polymerized efficiently and reduces the polymerization and curing time and the ultraviolet light exposure.

[0057] Examples of such photopolymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl)ketone, benzophenone, Examples of suitable benzoxanthone include benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylaminobenzoic acid ester, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]propanone], 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, etc. These may be used alone or in combination of two or more.

[0058] The content of the photopolymerization initiator in the composition C for hard coat layer is preferably 0.01 to 20 parts by mass, particularly preferably 0.1 to 10 parts by mass, and even more preferably 1 to 5 parts by mass, relative to 100 parts by mass of the curable component (A) (active energy ray-curable component). The photopolymerization initiator may be used in a form contained in a solution of the curable component (A).

[0059] (1-5-2) UV absorbers In order to improve the light resistance and weather resistance of the hard coat film 1, the composition C for hard coat layer preferably contains an ultraviolet absorber.

[0060] Examples of ultraviolet absorbers are not particularly limited, and include, for example, triazine compounds, benzophenone compounds, benzotriazole compounds, benzoate compounds, benzoxazinone compounds, phenyl salicylate compounds, cyanoacrylate compounds, and nickel complex compounds. These may be used alone or in combination of two or more. Among the above, triazine compounds, benzophenone compounds, and benzotriazole compounds are preferred, and triazine compounds are particularly preferred.

[0061] Examples of triazine compounds include 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3-5-triazine, 2-[4,6-di(2,4-xylyl)-1,3,5-triazin-2-yl]-5-octyloxyphenol, and the like.

[0062] Examples of benzophenone compounds include 2,2-dihydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid hydrate, and 2-hydroxy-4-n-octyloxybenzophenone.

[0063] Examples of benzotriazole compounds include 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, octyl-3-[3-t-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, and 2-ethylhexyl-3-[3-t-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate.

[0064] When the composition C for hard coat layer contains an ultraviolet absorber, the content of the ultraviolet absorber is preferably 0.1 to 10 parts by mass, more preferably 1 to 8 parts by mass, particularly preferably 2 to 6 parts by mass, and even more preferably 3 to 4 parts by mass, relative to 100 parts by mass of the curable component (A), thereby favorably improving the light resistance and weather resistance of the hard coat film 1.

[0065] (1-5-3) Light stabilizers In order to improve the light resistance and weather resistance of the hard coat film 1, the composition C for hard coat layer preferably contains a light stabilizer.

[0066] Examples of the light stabilizer are not particularly limited and include, for example, hindered amine light stabilizers, benzophenone light stabilizers, benzotriazole light stabilizers, etc. These light stabilizers may be used alone or in combination of two or more.

[0067] Among the above examples of light stabilizers, it is preferable to use a hindered amine light stabilizer, from the viewpoint of easily realizing excellent light resistance. Here, the hindered amine refers to an amine having substituents on both sides of an amino group. The hindered amine light stabilizer in this embodiment is represented by the following general formula (I): [ka] (In the formula, R 1 represents a hydrogen atom or an alkyl group. It is preferable that the compound contains at least one skeleton consisting of:

[0068] The hindered amine light stabilizer is represented by R 1However, it is preferably an alkyl group, particularly preferably an alkyl group having 1 to 4 carbon atoms, and further preferably a methyl group. That is, the hindered amine compound preferably has an N-alkyl group skeleton, particularly preferably an N-C1 to C4 alkyl group skeleton, and further preferably an N-CH3 skeleton.

[0069] The hindered amine light stabilizer preferably has one or more skeletons of the above general formula (I), more preferably 1 to 10, particularly preferably 1 to 7, further preferably 1 to 4, and most preferably 1 to 2. The skeleton of the above general formula (I) may be present at the terminal of the hindered amine light stabilizer, or in a side chain, or may be present at the terminal and in a side chain. When the hindered amine light stabilizer has one or two skeletons of the above general formula (I), it is preferable that they be present in the side chain.

[0070] When the hindered amine light stabilizer has two or more skeletons of the general formula (I), each R 1 may be the same or different.

[0071] The hindered amine light stabilizer is preferably a compound in which an oxygen atom of a —COO— skeleton is bonded to the carbon atom at the 4-position in the skeleton of the general formula (I) above.

[0072] The hindered amine light stabilizer may be a compound represented by the following structural formula (a): [ka] (wherein n is an integer of 1 or more). or a compound represented by the following structural formula (b): [ka] (In the formula, m is an integer of 1 or more.) It is particularly preferred that the compound is represented by the following formula:

[0073] In the compound represented by the structural formula (a), n is preferably 1-20, more preferably 3-15, and even more preferably 5-10.

[0074] In the compound represented by the structural formula (b), m is preferably 1 to 20, more preferably 3 to 15, and even more preferably 5 to 10. In the formula, R 2 is preferably an alkyl group, particularly preferably an alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group.

[0075] The compound represented by the structural formula (a) and the compound represented by the structural formula (b) can be used alone, but it is preferable to use them in combination.

[0076] When the composition C for hard coat layer contains a light stabilizer, the content of the light stabilizer is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, particularly preferably 1 to 5 parts by mass, and even more preferably 1.5 to 3 parts by mass, relative to 100 parts by mass of the curable component (A), thereby favorably improving the light resistance and weather resistance of the hard coat film 1.

[0077] (2) Thickness The thickness of the hard coat layer 12 is preferably 0.1 to 30 μm, more preferably 1 to 20 μm, particularly preferably 2 to 12 μm, further preferably 3 to 8 μm, and most preferably 4 to 6 μm, which further improves the adhesion of the hard coat layer 12 to another hard coat layer and allows the hard coat layer 12 to fully exhibit its functions.

[0078] 1-2.Base film The substrate film 11 is not particularly limited as long as it can form the above-mentioned hard coat layer 12. When the hard coat film 1 is used for optical purposes, it is preferable to use a resin film having a predetermined transparency.

[0079] Examples of such resin films include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin films such as polyethylene and polypropylene; cellophane; diacetyl cellulose films; triacetyl cellulose films; acetyl cellulose butyrate films; polyvinyl chloride films; polyvinylidene chloride films; polyvinyl alcohol films; ethylene-vinyl acetate copolymer films; polystyrene films; polycarbonate films; polymethylpentene films; polysulfone films; polyether ether ketone films; polyether sulfone films; polyetherimide films; fluororesin films; polyamide films; acrylic resin films; polyurethane resin films; norbornene polymer films; cyclic olefin polymer films; cyclic conjugated diene polymer films; and vinyl alicyclic hydrocarbon polymer films, or laminate films thereof. Among these, polyethylene terephthalate films, polycarbonate films, triacetyl cellulose films, and norbornene polymer films are preferred in terms of adhesion to the hard coat layer 12 and mechanical strength. In particular, a triacetyl cellulose film is preferred from the viewpoint of achieving excellent adhesion to the hard coat layer 12 by satisfying the above-mentioned surface silicon atomic ratio.

[0080] Furthermore, in order to improve adhesion to the hard coat layer 12, one or both surfaces of the base film 11 may be subjected to a surface treatment such as a primer treatment, an oxidation method, or a roughening method, as desired. Examples of oxidation methods include corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment, while examples of roughening methods include sandblasting and solvent treatment. These surface treatment methods are appropriately selected depending on the type of base material, but corona discharge treatment is generally preferred in terms of its effectiveness in improving adhesion and ease of use. The base film 11 may have an easy-adhesion layer on one or both surfaces of the resin film.

[0081] The thickness of the substrate film 11 is not particularly limited, but considering applications such as displays and touch panels, it is preferably 10 to 300 μm, more preferably 30 to 240 μm, particularly preferably 50 to 200 μm, and even more preferably 70 to 140 μm, which provides favorable handling properties and strength, and also makes it easier to achieve desired optical properties.

[0082] 1-3.Other elements The hard coat film 1 according to this embodiment may have a pressure-sensitive adhesive layer on the surface of the base film 11 opposite to the hard coat layer 12. The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is not particularly limited, and known pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, rubber pressure-sensitive adhesives, and silicone pressure-sensitive adhesives can be used, and it is preferable to use a pressure-sensitive adhesive having a predetermined transparency.

[0083] Furthermore, when the hard coat film 1 according to this embodiment includes the above-described pressure-sensitive adhesive layer, the hard coat film 1 according to this embodiment may have a release film laminated on the surface of the pressure-sensitive adhesive layer opposite to the base film 11. The release film is not particularly limited as long as it has the desired releasability on its release surface (the surface in contact with the pressure-sensitive adhesive layer), and any known release film, such as one in which one surface of a resin film has been subjected to a release treatment with a release agent, can be used.

[0084] 2. Manufacturing method of hard coat film The hard coat film 1 according to this embodiment can be produced by applying a coating liquid containing a composition C for a hard coat layer and, if desired, a solvent to a substrate film 11 and curing it to form a hard coat layer 12.

[0085] The solvent can be used to improve coating properties, adjust viscosity, adjust solid content concentration, etc., and any solvent can be used without particular limitation as long as it dissolves or disperses each component. Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, and γ-butyrolactone; ethers such as ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), diethylene glycol monobutyl ether (butyl cellosolve), and propylene glycol monomethyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; and amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone.

[0086] The coating solution of the composition C for hard coat layer may be applied by a conventional method, such as bar coating, knife coating, roll coating, blade coating, die coating, or gravure coating. After the coating solution of the composition for hard coat layer is applied, it is preferable to heat-dry the coating film at 40 to 120°C for about 30 seconds to 5 minutes.

[0087] When the composition C for hard coat layer contains an active energy ray-curable component as the curable component (A), the composition C for hard coat layer is cured by irradiating the coating film of the composition C for hard coat layer with active energy rays such as ultraviolet rays or electron beams. The ultraviolet irradiation can be carried out using a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, or the like, and the irradiation dose of the ultraviolet rays has an illuminance of 50 to 1000 mW / cm. 2, light intensity 50~1000mJ / cm 2 On the other hand, electron beam irradiation can be carried out using an electron beam accelerator or the like, and the irradiation dose of the electron beam is preferably about 10 to 1000 krad.

[0088] The coating film of the composition C for hard coat layer can be irradiated with active energy rays in an air atmosphere or an inert gas atmosphere. Depending on the type of active energy ray-curable component, the composition C for hard coat layer can be cured well without being inhibited by oxygen by irradiating with active energy rays in an inert gas atmosphere. This results in the hard coat layer 12 having better scratch resistance.

[0089] Examples of inert gases include nitrogen, argon, and helium, with nitrogen and argon being preferred, and nitrogen being particularly preferred. The oxygen concentration in the inert gas atmosphere is preferably 5% or less, more preferably 3% or less, and particularly preferably 2% or less.

[0090] 3. Physical properties of hard coat film (1) Total light transmittance The total light transmittance of the hard coat film 1 according to this embodiment is preferably 80% or more, more preferably 84% or more, particularly preferably 88% or more, and even more preferably 91% or more. This results in high transparency and makes the film particularly suitable for optical applications (displays). The method for measuring the total light transmittance in this specification is as shown in the test examples described below.

[0091] (2) Haze value The haze value of the hard coat film 1 according to this embodiment is preferably 30% or less, more preferably 22% or less, particularly preferably 14% or less, even more preferably 8% or less, and of these, preferably 6.5% or less. This provides high transparency and makes the film particularly suitable for optical applications (displays). The lower limit of the haze value is not particularly limited, but is preferably 0% or more, particularly more preferably 1% or more, even more preferably 3% or more, and of these, preferably 5% or more. The haze value is measured in this specification as shown in the test examples described below.

[0092] (3) 60° specular gloss The 60° specular gloss (gloss value) of the surface on the hard coat layer 12 side of the hard coat film 1 according to this embodiment is preferably 10 to 150%, more preferably 30 to 120%, particularly preferably 50 to 100%, even more preferably 60 to 90%, and most preferably 70 to 80%. This makes it easier to obtain optical properties such as low reflectivity, antiglare properties, and glare suppression. The 60° specular gloss in this specification is measured as shown in the test examples described below.

[0093] (4) Pencil hardness The pencil hardness of the surface of the hard coat layer 12 side of the hard coat film 1 according to this embodiment is preferably F or higher, more preferably H or higher, particularly preferably 2H or higher, and even more preferably 3H or higher. This gives the surface of the hard coat film 1 sufficient hardness and allows it to exhibit excellent scratch resistance. The upper limit of the pencil hardness is not particularly limited, but is preferably 6H or lower. The method for measuring the pencil hardness in this specification is as shown in the test examples described below.

[0094] (5) Scratch resistance The surface of the hard coat layer 12 side of the hard coat film 1 according to this embodiment was coated with #0000 steel wool at 250 g / cm2 The number of scratches generated when rubbed 10 times back and forth over a distance of 10 cm under a load of 10 ...

[0095] 4. Use of hard-coated film A desired hard coat layer can be laminated on the hard coat layer 12 of the hard coat film 1 according to this embodiment. The type of this hard coat layer is not particularly limited, and examples include an antistatic hard coat layer, an antiglare hard coat layer, an antireflection hard coat layer, a fingerprint-resistant hard coat layer, a refractive index adjusting hard coat layer, a writing feel improving hard coat layer, an infrared absorbing hard coat layer, an infrared reflecting hard coat layer, an anti-Newton ring hard coat layer, a light resistance improving hard coat layer, an antifogging hard coat layer, and a highly transparent hard coat layer.

[0096] The main component of the hard coat layer is preferably the active energy ray-curable component described in the hard coat layer 12. This improves the adhesion between the hard coat layer 12 and the hard coat layer.

[0097] The hard coat film 1 according to this embodiment can be preferably used for optical purposes, for example, and specifically can be used as a surface layer of various displays (display bodies) such as liquid crystal displays, organic EL displays, and even touch panels. More specifically, it is preferably used by being laminated on a cover material in a display having a display body module such as a liquid crystal (LCD) module, a light emitting diode (LED) module, or an organic electroluminescence (organic EL) module. The hard coat film 1 is preferably laminated on the cover material by being attached via the aforementioned pressure-sensitive adhesive layer.

[0098] 5. Display with hard-coated film A display with a hard coat film can be obtained by laminating the hard coat film 1 according to the embodiment described above onto a display main body. Specifically, the display with a hard coat film includes the hard coat film 1 and a display main body, and the substrate film 11 side of the hard coat film 1 is laminated onto the display surface side of the display main body. The hard coat film 1 may be laminated directly onto the display surface of the display main body, or may be laminated onto the display surface side of the display main body via another member or layer.

[0099] The above-described embodiments have been described to facilitate understanding of the present invention, and are not intended to limit the present invention. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0100] For example, another layer may be present on the surface of the hard coat layer 12 opposite to the substrate film 11, or another layer may be present on the surface of the substrate film 11 opposite to the hard coat layer 12. The hard coat layer 12 may be provided on both sides of the substrate film 11. Furthermore, when hard coat layers are provided on both sides of the substrate film 11, one hard coat layer may be the hard coat layer 12 of this embodiment, and the other hard coat layer may be a normal hard coat layer that does not satisfy the physical properties of this embodiment.

[0101] In this specification, when it is written "X to Y" (X and Y are any numbers), it means "X or more and Y or less" unless otherwise specified, and also includes the meaning "preferably greater than X" or "preferably smaller than Y." Furthermore, when it is written "X or more" (X is any number), it means "preferably greater than X" unless otherwise specified, and when it is written "Y or less" (Y is any number), it also means "preferably smaller than Y" unless otherwise specified. [Example]

[0102] The present invention will be explained in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0103] Example 1 (1) Preparation of hard coat layer composition 100 parts by mass (solid content equivalent; the same applies hereinafter) of an organic-inorganic hybrid resin (manufactured by Arakawa Chemical Industries, Ltd., product name "Opstar Z7530", containing a photopolymerization initiator) as the curable component (A) (active energy ray curable component), and an acrylic resin-based dispersant having a reactive group (manufactured by Kyoeisha Chemical Co., Ltd., product name "Florene" as the dispersant (B). A coating liquid of a composition for a hard coat layer was prepared by mixing 6.0 parts by mass of silicone filler (shape: spherical, average particle size: 4.5 μm, refractive index: 1.43) as the filler (C), 0.075 parts by mass of a fluorine-based leveling agent (manufactured by Neos Corporation, product name "Ftergent 602A") as the leveling agent (D), 3.0 parts by mass of a triazine-based ultraviolet absorber (manufactured by BASF Japan, product name "Tinuvin 400") as the ultraviolet absorber, and 2.0 parts by mass of a hindered amine-based light stabilizer (manufactured by BASF Japan, product name "Tinuvin 292") as the light stabilizer in propylene glycol monomethyl ether.

[0104] (2) Formation of hard coat layer The coating liquid of the composition for hard coat layer obtained in step (1) above was applied to one side of a triacetyl cellulose film (manufactured by Konica Minolta, Inc., product name "Konica Tack KC8UAW", thickness 80 μm) as a base film, and dried at 70°C for 1 minute.

[0105] Next, under a nitrogen atmosphere, the film was irradiated with ultraviolet light using an ultraviolet irradiation device (manufactured by Eye Graphics, product name "Eigrantage ECS-401GX type") under the following conditions to form a hard coat layer with a thickness of 5.0 μm, thereby obtaining a hard coat film consisting of a hard coat layer (5 μm) / triacetyl cellulose film.

[0106] [Ultraviolet irradiation conditions] Light source: High-pressure mercury lamp Lamp power: 2kW Conveyor speed: 4.23m / min ·Illuminance: 240mW / cm 2 ·Light amount: 307mJ / cm 2

[0107] [Example 2, Comparative Example 1] A hard coat film was produced in the same manner as in Example 1, except that the blending amounts of the dispersant (B) and the filler (C) were changed as shown in Table 1.

[0108] [Test Example 1] (X-ray photoelectron spectroscopy) The amounts (XPS counts) of carbon atoms (C), nitrogen atoms (N), oxygen atoms (O), silicon atoms (Si), and fluorine atoms (F) were measured (on the hard coat layer surface of the hard coat films produced in the Examples and Comparative Examples) by X-ray photoelectron spectroscopy (XPS) under the following conditions. The silicon atom ratio (atomic %) was then calculated according to the following formula. The results are shown in Table 2. Silicon atom ratio (atomic %) = {Si element amount / (C element amount + N element amount + O element amount + Si element amount + F element amount)} x 100

[0109] [XPS conditions] Measurement equipment: ULVAC, product name "PHI Quantera SXM" X-ray: AlKα (1486.6eV) Measurement elements: carbon (C), nitrogen (N), oxygen (O), silicon (Si), fluorine (F)

[0110] [Test Example 2] (Adhesion Evaluation) A coating liquid of a multifunctional acrylate resin (manufactured by Arakawa Chemical Industries, Ltd., product name "Opstar 575CB") was applied onto the hard coat layer (referred to as the "first hard coat layer") of the hard coat film produced in the Examples and Comparative Examples, and dried at 70°C for 1 minute.

[0111] Thereafter, ultraviolet light was irradiated under the same conditions as those for forming the first hard coat layer to form a hard coat layer (referred to as a "second hard coat layer") having a thickness of 1.0 μm, which was used as a sample.

[0112] One hundred 1mm squares were formed on the two hard coat layers of the sample using a cutter knife in accordance with JIS K5600-5-6. Next, adhesive tape (cellophane tape manufactured by Nichiban Co., Ltd.) was applied to the grid using a squeegee at 23°C and 50% RH. Thirty seconds after application, the adhesive tape was peeled off at a 90° angle. The number of grids from the second hard coat layer remaining on the first hard coat layer without detaching from the first hard coat layer was counted. Based on this number, the adhesion between the first and second hard coat layers was evaluated according to the following criteria. The results are shown in Table 2. ○: The number of remaining grids was 100. ×: The number of remaining grids was less than 100.

[0113] [Test Example 3] (Measurement of total light transmittance) The total light transmittance (%) of the hard coat films produced in the examples and comparative examples was measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "NDH5000") in accordance with JIS K7361-1:1997. The results are shown in Table 2.

[0114] [Test Example 4] (Haze Value Measurement) The haze values ​​(%) of the hard coat films produced in the examples and comparative examples were measured in accordance with JIS K7136:2000 using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "NDH5000") The results are shown in Table 2.

[0115] [Test Example 5] (Measurement of 60° specular gloss) The 60° specular gloss (gloss value, %) of the surface of the hard coat layer side of the hard coat films produced in the examples and comparative examples was measured using a gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS Z8741-1997. The results are shown in Table 2.

[0116] [Test Example 6] (Measurement of pencil hardness) The pencil hardness of the surface of the hard coat layer side of the hard coat films produced in the examples and comparative examples was measured in accordance with JIS K5600 using an electric pencil scratch hardness tester (manufactured by Yasuda Seiki Seisakusho, product name "No. 553-M1") The results are shown in Table 2.

[0117] [Test Example 7] (Scratch Resistance Evaluation) The surface of the hard coat layer of each of the hard coat films produced in the examples and comparative examples was wiped with #0000 steel wool at 250 g / cm 2 The film was rubbed 10 times back and forth over a distance of 10 cm with a load of 0.015. The surface of the hard coat film was visually inspected under a three-wavelength fluorescent lamp, and the number of scratches that had occurred was counted. The scratch resistance was then evaluated according to the following criteria. The results are shown in Table 2. A: The number of scratches was 0. B: The number of scratches was one or more but less than three. C: The number of scratches was 3 or more but less than 10. D: The number of scratches was 10 or more.

[0118] [Table 1]

[0119] [Table 2]

[0120] As is clear from Table 2, the hard-coated films produced in the examples had excellent adhesion to other hard-coat layers. Furthermore, the hard-coated films produced in the examples also had excellent optical properties and were suitable for optical applications. [Industrial Applicability]

[0121] The hard coat film according to the present invention is suitably used as a surface layer of a display or a touch panel. [Explanation of symbols]

[0122] 1...Hard coat film 11...Base film 12...Hard coat layer

Claims

1. A hard coat film comprising a substrate film and a hard coat layer provided on at least one surface of the substrate film, The silicon atomic ratio measured by X-ray photoelectron spectroscopy on the surface of the hard coat layer opposite to the substrate film is 1 atomic % or more and 14 atomic % or less. A hard coat film characterized by:

2. 2. The hard coat film according to claim 1, wherein the hard coat layer contains a dispersant.

3. 3. The hard coat film according to claim 2, wherein the content of the dispersant in the hard coat layer is 0.5% by mass or more and 35% by mass or less.

4. 3. The hard coat film according to claim 2, wherein the dispersant is an acrylic resin having a reactive group.

5. 2. The hard coat film according to claim 1, wherein the hard coat layer is formed by curing a composition for a hard coat layer containing an organic-inorganic hybrid resin.

6. 2. The hard coat film according to claim 1, wherein the hard coat layer contains a silicone filler.

7. 2. The hard coat film according to claim 1, wherein the hard coat layer contains a leveling agent.

8. 2. The hard coat film according to claim 1, wherein the substrate film is a polyethylene terephthalate film, a polycarbonate film, a triacetyl cellulose film, or a norbornene-based polymer film.

9. 2. The hard coat film according to claim 1, wherein the thickness of the hard coat layer is 0.1 μm or more and 30 μm or less.

10. 10. The hard coat film according to claim 1, which is for optical use.

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