WO2019171989A1

WO2019171989A1 - Hard coat film, and hard coat film having scratch-resistant layer attached thereto

Info

Publication number: WO2019171989A1
Application number: PCT/JP2019/006866
Authority: WO
Inventors: 千裕増田; 悠太福島; 彩子松本
Original assignee: 富士フイルム株式会社
Priority date: 2018-03-09
Filing date: 2019-02-22
Publication date: 2019-09-12
Also published as: JPWO2019171989A1; JP2022115882A; JP7064573B2

Abstract

The present invention provides: a hard coat film provided with a hard coat layer formed on at least one surface of a substrate, wherein the hard coat layer contains a matrix component and inorganic microparticles having an average primary particle diameter of 3 to 100 nm, the content of the inorganic microparticles in the hard coat layer is 50 to 90 vol% inclusive, and specific relation formulae are satisfied in such an indentation test that a load is applied in the vertical direction against a surface of the hard coat layer which is opposed to the substrate side of the hard coat layer using a diamond-made knoop indenter, wherein E₁₀ represents the indentation elastic modulus obtained when the indenter is indented by 10% relative to the thickness of the hard coat layer and E₂ represents the indentation elastic modulus obtained when the indenter is indented by 2% relative to the thickness of the hard coat layer; and a hard coat film having a scratch-resistant layer attached thereto. (1) E₁₀ − E₂ ≥ 2 GPa; (2) E₁₀ ≥ 8 GPa; and (3) E₂ ≤ 8 GPa

Description

Hard coat film and hard coat film with scratch-resistant layer

The present invention relates to a hard coat film and a hard coat film with a scratch-resistant layer.

Thin and hard glass such as chemically tempered glass is often used on the surface of mobile displays such as smartphones and tablets for the necessity of withstanding touch panel operations and pen input and for protecting the display portion. On the other hand, glass basically has a hard property, but has a problem that it is heavy and easily broken.
Various proposals have been made because it is considered that there is a merit that it is light and not broken if there is a plastic film that is hard and transparent like glass. For example, a film having excellent transparency, surface hardness, and scratch resistance has been proposed by applying a hard coat layer composed of an organic resin and metal oxide particles on the surface of a transparent resin film (Patent Document 1).

However, in recent years, there has been an increasing need for flexible displays, and existing techniques are not flexible and are not suitable for surface protection of flexible displays.
For example, Patent Document 2 includes a first hard coat layer containing a polyfunctional (meth) acrylate cured product and silica fine particles and a polyfunctional (meth) acrylate monomer cured product on a base film. By providing the second hard coat layer, a hard coat film for a touch panel, which has some excellent hardness, scratch resistance, and durable folding performance, has been proposed.

Japanese Unexamined Patent Publication No. 2016-01217 Japanese Unexamined Patent Publication No. 2017-33032

However, in Patent Document 2, it is difficult to say that the bending radius in the durability folding test is large and the repeated bending resistance is sufficient.
An object of the present invention is to provide a hard coat film having high hardness and excellent repeated bending resistance, and a hard coat film with a scratch-resistant layer having excellent scratch resistance.

The present inventors diligently studied and found that the above problems can be solved by the following means.
[1]
A hard coat film having a hard coat layer on at least one surface of a support,
The hard coat layer includes a matrix component and inorganic fine particles having an average primary particle size of 3 to 100 nm,
The content of the inorganic fine particles in the hard coat layer is 50% by volume or more and 90% by volume or less,
Indentation when the hard coat layer is indented by 10% with respect to the thickness of the hard coat layer in an indentation test in which a load is applied perpendicularly from the surface opposite to the support side using a diamond knoop indenter. When the elastic modulus is E ₁₀ and the indentation elastic modulus when indented by 2% with respect to the thickness of the hard coat layer is E ₂ , the following formulas (1), (2), and (3) are satisfied. A hard coat film.
E ₁₀ −E ₂ ≧ 2 GPa (1)
E ₁₀ ≧ 8 GPa (2)
E ₂ ≦ 8 GPa (3)
[2]
The hard coat film according to [1], wherein E _M ≦ 1.5 GPa when the indentation elastic modulus of the matrix component is E _M.
[3]
The matrix component is a cured product of the matrix forming composition,
The hard coat film of [1] or [2], wherein the polymerizable functional group equivalent in the matrix-forming composition is 250 or more.
[4]
The hard coat film according to any one of [1] to [3], wherein the inorganic fine particles are particles modified with a silane coupling agent having two or more polymerizable functional groups in one molecule.
[5]
From [1], the support is selected from a triacetyl cellulose film, a polymethyl methacrylate film, a polyamide film, an aramid film, a polyimide film, a polyamideimide film, a polyetherimide film, a polyesterimide film, and a polyethylene terephthalate film. [4] The hard coat film.
[6]
A hard coat film with a scratch-resistant layer having a scratch-resistant layer on the surface of the hard coat film of [1] to [5] opposite to the support side of the hard coat layer.

According to the present invention, it is possible to provide a hard coat film having high hardness and excellent repeated bending resistance, and a hard coat film with a scratch-resistant layer having excellent scratch resistance.

Hereinafter, although the form for implementing this invention is demonstrated in detail, this invention is not limited to these. In this specification, when a numerical value represents a physical property value, a characteristic value, or the like, the description “(numerical value 1) to (numerical value 2)” means “(numerical value 1) or more (numerical value 2) or less” . In the present specification, the description “(meth) acrylate” means “at least one of acrylate and methacrylate”. The same applies to “(meth) acrylic acid”, “(meth) acryloyl” and the like.

[Hard coat film]
The hard coat film of the present invention is
A hard coat film having a hard coat layer on at least one surface of a support,
The hard coat layer includes a matrix component and inorganic fine particles having an average primary particle size of 3 to 100 nm,
The content of the inorganic fine particles in the hard coat layer is 50% by volume or more and 90% by volume or less,
Indentation when the hard coat layer is indented by 10% with respect to the thickness of the hard coat layer in an indentation test in which a load is applied perpendicularly from the surface opposite to the support side using a diamond knoop indenter. A hard coat that satisfies the following formulas (1), (2), and (3) when the elastic modulus is E ₁₀ and the indentation elastic modulus when indented by 2% with respect to the thickness of the hard coat layer is E ₂ It is a film.
E ₁₀ −E ₂ ≧ 2 GPa (1)
E ₁₀ ≧ 8 GPa (2)
E ₂ ≦ 8 GPa (3)

Variations in the thickness direction by stress at the time of the pencil hardness test (approximately 10% of the thickness), but, better higher elastic modulus E ₁₀ during its deformation. More E ₁₀ higher more deformation hardly occur, because it does not reach the deformation of the brittle fracture region, it is possible to increase the pencil hardness. On the other hand, folding the repeated bending is to give repeated small strain amount of about 2%, the better low modulus of elasticity E ₂ when pushed two percent. Repeat fine cracks in the film inside folding occurred, it is considered to lead to the spread rupture, by reducing the elastic modulus E ₂ in the bending deformation area, it is possible to stress cracks do not occur, repeat Bending resistance can be imparted. Generally, the hardness and the repeated bending resistance are not compatible, but the present inventors pay attention to the difference in deformation amount in these tests and set E ₁₀ and E ₂ in the range satisfying the formulas (1) to (3). I found out that it is compatible.

(Indentation modulus)
The hard coat film of the present invention has an indentation elastic modulus shown below in an indentation test in which a load is applied vertically from the surface of the hard coat layer opposite to the support side using a diamond knoop indenter. A detailed method for measuring the indentation elastic modulus will be described later.
Indentation modulus _{E 2} 2% pushing do it when the thickness of the hard coat layer is less 8 GPa, preferably not more than 7.5 GPa, more preferably at most 7 GPa. The E ₂ With this range, the hard coat film is obtained having excellent bending resistance of repetition.
The lower limit of E ₂ is not particularly limited, but may be, for example, 1 MPa (0.001 GPa) or more.
Also, indentation modulus _{E 10} 10% indentation do it when the thickness of the hard coat layer is not less than 8 GPa, is preferably not less than 9 GPa. The E ₁₀ With this range, high hardness hard coat film is obtained.
No particular limitation is imposed on the upper limit of the E _10, for example, it may be less 80 GPa.
Further, E ₁₀ -E ₂ is 2 GPa or more, preferably 2.5 GPa or more.

(Repeated bending resistance)
The repeated bending resistance of the hard coat film is preferably 500,000 times or more until the hard coat film is cracked or broken when the hard coat layer is inside and the hard coat film is bent with a bending radius of 1.0 mm. , More preferably 800,000 times or more, and even more preferably 1,000,000 times or more. A detailed measurement method of the bending test will be described later.

(Pencil hardness)
The hardness of the hard coat film is preferably 5H or higher, more preferably 6H or higher, and more preferably 8H or higher, as measured in accordance with Japanese Industrial Standard (JIS) K5600-5-4 (1999). Is more preferable.

<Support>
The support of the hard coat film of the present invention will be described.

The support preferably has a visible light region transmittance of 70% or more, more preferably 80% or more, and still more preferably 90% or more. The support preferably includes a polymer resin.

(Polymer resin)
As the polymer resin, a polymer excellent in optical transparency, mechanical strength, thermal stability and the like is preferable.

Examples include polycarbonate polymers, polyester polymers such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and styrene polymers such as polystyrene and acrylonitrile / styrene copolymer (AS resin). Polyolefins such as polyethylene and polypropylene, polyolefin polymers such as norbornene resins, ethylene / propylene copolymers, (meth) acrylic polymers such as polymethyl methacrylate, vinyl chloride polymers, amides such as nylon and aromatic polyamides Polymer, imide polymer, sulfone polymer, polyether sulfone polymer, polyether ketone polymer, polyphenylene sulfide polymer, vinylidene chloride polymer, vinyl alcohol polymer, vinyl butyral polymer, arylate polymer, polyoxymethylene Polymers, epoxy polymers, cellulose polymers represented by triacetyl cellulose, copolymers of the above polymers, Ma may also be mentioned as an example.

The support may be any one selected from a triacetyl cellulose film, a polymethyl methacrylate film, a polyamide film, an aramid film, a polyimide film, a polyamideimide film, a polyetherimide film, a polyesterimide film, and a polyethylene terephthalate film. preferable.

In particular, amide-based polymers and imide-based polymers such as aromatic polyamides can be preferably used as a support because they have a large number of times of bending at break measured by an MIT tester in accordance with JIS P8115 (2001) and a relatively high hardness. . For example, aromatic polyamides as described in Example 1 of Japanese Patent No. 5699454, polyimides described in Japanese Patent Publication Nos. 2015-508345 and 2016-521216 can be preferably used as the support.

The support can also be formed as a cured layer of an ultraviolet-curing or thermosetting resin such as acrylic, urethane, acrylic urethane, epoxy, or silicone.

(Flexible material)
The support may contain a material that further softens the polymer resin. The softening material refers to a compound that improves the number of breaks and folds. As the softening material, a rubber elastic body, a brittleness improving agent, a plasticizer, a slide ring polymer, or the like can be used.
Specifically, as the softening material, the softening materials described in paragraph numbers [0051] to [0114] in JP-A No. 2016-170443 can be suitably used.

The softening material may be mixed with the polymer resin alone, or a plurality of softening materials may be used in combination as appropriate, or only the softening material may be used alone or in combination without mixing with the resin. It may be used as a support.

The amount of these softening materials to be mixed is not particularly limited, and a polymer resin having a sufficient number of times of bending and bending alone may be used alone as a film support, or a softening material may be mixed. All may be made flexible enough (100%) to have a sufficient number of breaks and folds.

(Other additives)
Various additives (for example, an ultraviolet absorber, a matting agent, an antioxidant, a peeling accelerator, a retardation (optical anisotropy) adjusting agent, etc.) can be added to the support. They may be solid or oily. That is, the melting point or boiling point is not particularly limited. The additive may be added at any time in the step of producing the support, or may be added to the material preparation step by adding the preparation step. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested.
As other additives, the additives described in paragraph numbers [0117] to [0122] in JP-A No. 2016-167043 can be suitably used.

The above additives may be used alone or in combination of two or more.

(UV absorber)
Examples of the ultraviolet absorber include benzotriazole compounds, triazine compounds, and benzoxazine compounds. Here, the benzotriazole compound is a compound having a benzotriazole ring, and specific examples include various benzotriazole ultraviolet absorbers described in paragraph 0033 of JP2013-111835A. The triazine compound is a compound having a triazine ring, and specific examples thereof include various triazine-based UV absorbers described in paragraph 0033 of JP2013-111835A. As the benzoxazine compound, for example, those described in paragraph 0031 of JP 2014-209162 A can be used. The content of the ultraviolet absorber in the support is, for example, about 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin contained in the support, but is not particularly limited. Regarding the UV absorber, reference can also be made to paragraph 0032 of JP2013-111835A. In the present invention, an ultraviolet absorber having high heat resistance and low volatility is preferable. Examples of such UV absorbers include UVSORB 101 (manufactured by Fujifilm Fine Chemicals Co., Ltd.), TINUVIN 360, TINUVIN 460, TINUVIN 1577 (manufactured by BASF), LA-F70, LA-31, LA-46 (manufactured by ADEKA). Etc.

From the viewpoint of transparency, the support preferably has a small difference in refractive index between the flexible material and various additives used for the support and the polymer resin.

(Thickness of the support)
The thickness of the support is more preferably 100 μm or less, further preferably 80 μm or less, and most preferably 50 μm or less. If the thickness of the support is reduced, the difference in curvature between the front and back surfaces at the time of bending is reduced, cracks and the like are less likely to occur, and the support is not broken even when bent multiple times. On the other hand, from the viewpoint of ease of handling the support, the thickness of the support is preferably 3 μm or more, more preferably 5 μm or more, and most preferably 15 μm or more.

(Method for producing support)
The support may be formed by thermally melting a thermoplastic polymer resin, or may be formed by solution film formation (solvent casting method) from a solution in which the polymer is uniformly dissolved. In the case of hot melt film formation, the above-mentioned softening material and various additives can be added at the time of hot melting. On the other hand, when the support is produced by a solution casting method, the above-described softening material and various additives can be added to a polymer solution (hereinafter also referred to as a dope) in each preparation step. Further, the addition may be performed at any time in the dope preparation process, but may be performed by adding an additive to the final preparation process of the dope preparation process.

<Hard coat layer>
The hard coat layer of the hard coat film of the present invention will be described. The hard coat layer contains a matrix component and inorganic fine particles.

(Matrix component)
Matrix components, from the viewpoint of bending resistance of the repetition, it is preferred that the indentation modulus _{E M} or less 1.5GPa than 0.001 GPa, more preferably less than 0.01 GPa 1.0 GPa, 0.1 GPa More preferably, it is 0.5 GPa or less. Here, the indentation elastic modulus E _M of the matrix component is 2 with respect to the thickness of the matrix layer in the indentation test in which a load is applied perpendicularly to the layer composed of the matrix component (matrix layer) using a diamond knoop indenter. % Is the indentation elastic modulus when indented. As will be described later, when the matrix component is a cured product of the matrix forming composition, in the indentation test in which a load is applied vertically to the layer formed by curing the matrix forming composition using a diamond knoop indenter. The indentation elastic modulus when indented 2% with respect to the thickness of the matrix layer.

The matrix component is preferably a polymer (cured product) obtained by polymerizing a composition for forming a matrix containing a compound having a polymerizable functional group by irradiation with ionizing radiation or heating. Furthermore, in order to range the indentation modulus E _M described above, it is preferable that the polymerizable functional group equivalent in the matrix forming composition is 250 or more, and more preferably 250 to 1,000. In addition, when the polymerizable functional group equivalent in the composition for forming a matrix is too large, chemical bonds with functional groups modified on the surface of the inorganic fine particles described later are reduced, and the hardness and repeated bending resistance are deteriorated. However, the bonding can be compensated by making the average primary particle size of the inorganic fine particles and the surface modifier appropriate.

The polymerizable functional group equivalent e in the composition for forming a matrix is obtained from the following formula (4).
In the formula, for component 1, component 2,..., Component n contained in the matrix-forming composition, the mass ratio of each component is R ₁ , R ₂ ,... R _n , and the weight average molecular weight (low molecular weight of each component). _M 1 for compounds of molecular weight), _{_{respectively, M 2, ..., M n}} , C 1 polymerizable functional groups in one molecule of each component, _{respectively,} C _{2, ...,} expressed as _{C n.}
In the present specification, the weight average molecular weight (Mw) can be measured as a molecular weight in terms of polystyrene by gel permeation chromatography (GPC) unless otherwise specified. At this time, HLC-8220 (manufactured by Tosoh Corporation) is used as the GPC apparatus, G3000HXL + G2000HXL is used as the column, the flow rate is 1 mL / min at 23 ° C., and the refractive index (RI) is detected. The eluent can be selected from THF (tetrahydrofuran), chloroform, NMP (N-methyl-2-pyrrolidone), m-cresol / chloroform (manufactured by Shonan Wako Pure Chemical Industries, Ltd.) and can be dissolved. In this case, THF is used.

(Compound having a polymerizable functional group)
The composition for forming a matrix contains at least a compound having a polymerizable functional group. As the compound having a polymerizable functional group, various monomers, oligomers and polymers can be used, and the polymerizable functional group (polymerizable group) is preferably a light, electron beam or radiation-polymerizable one. A functional group is preferred.

Examples of photopolymerizable functional groups include polymerizable unsaturated groups (carbon-carbon unsaturated double bond groups) such as (meth) acryloyl groups, vinyl groups, styryl groups, and allyl groups, epoxy groups, oxetanyl groups, and the like. Examples thereof include a ring polymerizable group, and among them, a (meth) acryloyl group is preferable.

Specific examples of the compound having a (meth) acryloyl group include (meth) acrylic acid diesters of alkylene glycol such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, propylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyoxyalkylene glycols such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate;
(Meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate;
(Meth) acrylic acid diesters of ethylene oxide or propylene oxide adducts such as 2,2-bis {4- (acryloxy-diethoxy) phenyl} propane and 2-2bis {4- (acryloxy-polypropoxy) phenyl} propane And the like.
Furthermore, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates are also preferably used as the photopolymerizable monomer.

In order to set the polymerizable functional group equivalent in the composition for forming a matrix to 250 or more and 1000 or less, the compound having a polymerizable functional group is preferably a compound having a polymerizable functional group equivalent of 250 or more and 1000 or less. Further, two or more kinds of compounds having a polymerizable functional group may be used in combination, and at this time, the combination of a compound having a polymerizable functional group equivalent of 250 or more and a compound of 250 or less in the composition for forming a matrix. The polymerizable functional group equivalent may be adjusted to be 250 or more and 1000 or less.
The polymerizable functional group equivalent for the compound having a polymerizable functional group is the number C of the polymerizable functional groups in one molecule of the compound having a polymerizable functional group, the molecular weight or the weight average molecular weight M of the compound having a polymerizable functional group. The value divided by (M / C).

When the compound having a polymerizable functional group is a monomer, a compound having 1 or more and 6 or less polymerizable functional groups in one molecule is preferable, a compound having 1 or more and 3 or less is more preferable, and 2 Certain compounds are particularly preferred. When the compound having a polymerizable functional group is an oligomer or polymer, the polymerizable functional group may be present at the end of the main chain or may be present in the side chain.

Specific examples of the compound having a polymerizable functional group equivalent of 250 or more include DPCA-120 (molecular weight 1947, polymerizable functional group number 6, polymerizable functional group equivalent 325) manufactured by Nippon Kayaku Co., Ltd., Nippon Synthetic Chemical Co., Ltd. Violet UV-3000B (molecular weight 18000, functional group number 2, functional group equivalent 9000), UV-3200B (molecular weight 10,000, functional group number 2, functional group equivalent 5000), UV-3210EA (molecular weight 9000, functional group number 2, functional group) Group equivalent 4500), UV-3310B (molecular weight 5000, functional group number 2, functional group equivalent 2500), UV-3700B (molecular weight 38000, functional group number 2, functional group equivalent 19000), UV-6640B (molecular weight 5000, functional group) 2 groups, functional group equivalent 2500), UV-2000B (molecular weight 13000, functional group number 2, functional group equivalent 65) 0), the same UV-2750B (molecular weight 3000, functional group number 2, functional group equivalent 1500), Shin-Nakamura Chemical Co., Ltd. ATM-35E (molecular weight 1892, functional group number 4, functional group equivalent 473) A-GLY-9E (Molecular weight 811, functional group number 3, functional group equivalent 270), A-GLY-20E (molecular weight 1295, functional group number 3, functional group equivalent 432), A-400 (molecular weight 508, functional group number 2, functional group equivalent 254) ), A-600 (molecular weight 708, functional group number 2, functional group equivalent 354), A-1000 (molecular weight 1108, functional group number 2, functional group equivalent 554), UA-160TM (molecular weight 2700, functional group number 2, Functional group equivalent 1350), UA-290TM (molecular weight 2900, functional group number 2, functional group equivalent 1450), UA-4200 (molecular weight 1000, functional group number 2, Functional group equivalent 500), the UA-4400 (molecular weight 1400, functionality 2, functional group equivalent 700), and the like.

The content of the matrix component in the hard coat layer is preferably 10 to 50% by volume, and more preferably 25 to 45% by volume.

(Polymerization initiator)
The composition for forming a matrix may contain a polymerization initiator.

When the compound having a polymerizable functional group is a photopolymerizable compound, it preferably contains a photopolymerization initiator.
As photopolymerization initiators, acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds, Examples include fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, and coumarins. Specific examples, preferred embodiments, commercially available products, and the like of the photopolymerization initiator are described in paragraphs [0133] to [0151] of JP-A-2009-098658, and can be suitably used in the present invention as well. it can.
“Latest UV Curing Technology” {Technical Information Association, Inc.} (1991), p. 159, and “UV Curing System” written by Kiyomi Kato (published by the General Technology Center in 1989), p. Various examples are also described in 65 to 148 and are useful in the present invention.
The content of the polymerization initiator in the matrix forming composition is preferably 0.5 to 8% by mass, more preferably 1 to 5% by mass, based on the total solid content in the matrix forming composition.

(Other additives)
The composition for forming a matrix may contain components other than those described above, and may contain, for example, a dispersant, a leveling agent, an antifouling agent, an antistatic agent, an ultraviolet absorber, and the like.

(Inorganic fine particles)
The hard coat layer of the hard coat film of the present invention contains inorganic fine particles.
The hardness can be increased by adding inorganic fine particles to the hard coat layer. Examples of the inorganic fine particles include silica particles, titanium dioxide particles, zirconia particles, aluminum oxide particles, diamond powder, sapphire particles, boron carbide particles, silicon carbide particles, and antimony pentoxide particles. Of these, silica particles and zirconia particles are preferable from the viewpoint of ease of modification.

The surface of the inorganic fine particles is preferably treated with a surface modifier containing an organic segment. The surface modifier preferably has a functional group capable of forming a bond with inorganic fine particles or adsorbing to the inorganic particle and a functional group having high affinity with the organic component in the same molecule. Examples of the surface modifier having a functional group capable of binding or adsorbing to inorganic fine particles include metal alkoxide surface modifiers such as silane, aluminum, titanium, and zirconium, phosphate groups, sulfate groups, sulfonate groups, carboxylic acid groups, and the like. A surface modifier having an anionic group is preferred, and among these, a silane alkoxide surface modifier (silane coupling agent) is preferred from the viewpoint of ease of modification. Furthermore, the functional group having a high affinity with the organic component may be simply a combination of the matrix component and the hydrophilicity / hydrophobicity, but a functional group that can be chemically bonded to the matrix component is preferable, particularly an ethylenically unsaturated double bond. A linking group or a ring-opening polymerizable group is preferred. A preferred inorganic fine particle surface modifier in the present invention is a curable resin having a metal alkoxide or an anionic group and an ethylenically unsaturated double bond group or a ring-opening polymerizable group in the same molecule. The number of ethylenically unsaturated double bond groups or ring-opening polymerizable groups in the same molecule is preferably 1.0 or more and 5.0 or less, and more preferably 1.1 or more and 3.0 or less. By setting the number of ethylenically unsaturated double bond groups or ring-opening polymerizable groups in the same molecule within the above range, the bond between the matrix component and the inorganic fine particles can be strengthened.

Specific examples of the silane coupling agent include, for example, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropyldimethylmethoxysilane, 3- (Meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 2- (meth) acryloxyethyltrimethoxysilane, 2- (meth) acryloxyethyltriethoxysilane, 4- ( Silane coupling agents having an ethylenically unsaturated double bond group such as (meth) acryloxybutyltrimethoxysilane, 4- (meth) acryloxybutyltriethoxysilane, and 2- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, 3-glycidoxypropi Silane coupling agent having a ring-opening polymerizable group such as trimethoxysilane. More specifically, KBM-303, KBM-403, KBM-503, KBM-5103 (all manufactured by Shin-Etsu Chemical Co., Ltd.) and silane coupling agents C-1, C represented by the following structural formula -2 etc.

The inorganic fine particles are more preferably particles modified with a silane coupling agent having two or more polymerizable functional groups in one molecule.

The inorganic fine particles preferably have 0.2 to 4.0 surface modifiers bonded or adsorbed per 1 nm ² of the surface area of the inorganic fine particles, more preferably 0.5 to 3.0 particles per 1 nm ² , and 1 nm. More preferably, 0.8 to 2.0 per ^two . If the number is less than 0.2 per 1 nm ² , sufficient surface modification effects may not be obtained. On the other hand, when the number is more than 4.0 per 1 nm ² , a modifying agent released from the surface of the inorganic fine particles tends to be generated.

The surface modification of these inorganic fine particles is preferably performed in a solution. After synthesizing the inorganic fine particles in the solution, the surface modifier is added and stirred, or when the inorganic fine particles are mechanically finely dispersed, the surface modifier is present together or after the fine inorganic particles are finely dispersed. Add the surface modifier to the mixture and stir, or further modify the surface before finely dispersing the inorganic fine particles (if necessary, heat, dry, or change pH), then fine A method of performing dispersion may be used. As the solution for dissolving the surface modifier, an organic solvent having a large polarity is preferable. Specific examples include known solvents such as alcohols, ketones and esters.

The average primary particle size of the inorganic fine particles is 3 to 100 nm, preferably 4 to 50 nm, and more preferably 5 to 20 nm. By setting the average primary particle size within the above range, the bond between the matrix component and the inorganic fine particles can be strengthened.
The average primary particle size of the inorganic fine particles in the hard coat film is obtained by observing the cross section of the thin sample obtained by slicing the hard coat film at an appropriate magnification (about 400,000 times) using a transmission electron microscope (TEM). Observe, measure the diameter of each of the 100 primary particles, calculate the volume, and determine the cumulative 50% particle size as the average primary particle size. When the particles are not spherical, the average value of the major and minor diameters is regarded as the diameter of the primary particles. The flake sample can be prepared by a microtome method using a cross-section cutting apparatus ultramicrotome, a flake processing method using a focused ion beam (FIB) apparatus, or the like. When measuring the particles in the powder particles or the particle dispersion, the average primary particle size is calculated by observing the powder particles or the particle dispersion with a TEM as described above.

Inorganic fine particles may be used alone or in combination of two or more. When using 2 or more types together, it is preferable to use those having different particle diameters from the viewpoint of increasing the volume filling rate of the particles in the hard coat layer.

The volume ratio of the inorganic fine particles in the hard coat layer is 50% by volume or more and 90% by volume or less. By setting it to 50% by volume or more, E ₁₀ -E ₂ of the hard coat film can be made 2 GPa or more. Moreover, it becomes easy to form a film | membrane by setting it as 90 volume% or less.

The inorganic fine particles are preferably solid particles from the viewpoint of particle strength. The shape of the inorganic fine particles is most preferably spherical, but may be other than spherical such as indefinite.

(Film thickness)
The thickness of the hard coat layer is not particularly limited, but is preferably 1 to 50 μm, more preferably 5 to 30 μm, and still more preferably 10 to 20 μm.
The thickness of the hard coat layer is calculated by observing the cross section of the hard coat film with an optical microscope. The cross-section sample can be created by a microtome method using a cross-section cutting apparatus ultramicrotome, a cross-section processing method using a focused ion beam (FIB) apparatus, or the like.

<Other layers>
The hard coat film of the present invention may have a layer other than the hard coat layer. For example, an aspect having an easy-adhesion layer for improving adhesion between the substrate and the hard coat layer, an aspect having an antistatic layer for imparting antistatic properties, An embodiment having an antifouling layer for imparting dirtiness and an abrasion resistant layer for imparting scratch resistance is preferably exemplified, and a plurality of these may be provided.
For example, it is also preferable to further provide a scratch-resistant layer on the outermost surface of the hard coat film opposite to the support of the hard coat layer, whereby the scratch resistance can be improved.
A hard coat film having a hard coat layer satisfying the formulas (1) to (3) in the present invention is prepared as a hard coat layer forming composition (coating liquid) containing the matrix forming composition and inorganic fine particles described above. The composition for forming a hard coat layer is preferably applied to a support and cured by light or heat to form a hard coat layer. The hard coat film with a scratch-resistant layer of the present invention is formed on the hard coat layer of the hard coat film of the present invention by forming a scratch-resistant layer containing a compound having 3 or more polymerizable functional groups in one molecule described later. It is preferable to manufacture by applying a composition for coating (coating liquid) and curing it by light or heat to form a scratch-resistant layer.

The composition for forming a hard coat layer preferably contains an organic solvent. As an organic solvent, it is preferable from the viewpoint of improving dispersibility to select an organic solvent having a polarity close to that of inorganic fine particles. The organic solvent is not particularly limited, and examples thereof include organic solvents such as alcohol solvents, ketone solvents, ester solvents, carbonate solvents, and aromatic solvents. These organic solvents may be used in a mixture of a plurality of types as long as the dispersibility is not significantly deteriorated.

(Abrasion resistant layer)
The scratch-resistant layer is preferably a layer containing 80% by mass or more of a cured product of a compound having 3 or more polymerizable functional groups in one molecule with respect to the total mass of the scratch-resistant layer.

The compound having three or more polymerizable functional groups in one molecule may be a monomer, an oligomer, or a polymer. When the number of polymerizable functional groups in one molecule of the compound is 3 or more, a dense three-dimensional cross-linked structure is easily formed, and the polymerizable functional group equivalent (in the case of having a (meth) acryloyl group as the polymerizable functional group) The indentation hardness of the scratch-resistant layer can be increased even when a small compound (called an acrylic equivalent) is used. The indentation hardness of the scratch-resistant layer is preferably 300 MPa or more.
The content of the cured product of the compound having three or more polymerizable functional groups in one molecule is more preferably 85% by mass or more, and still more preferably 90% by mass or more with respect to the total mass of the scratch-resistant layer.

The polymerizable functional group is preferably a (meth) acryloyl group, an epoxy group, or an oxetanyl group, more preferably a (meth) acryloyl group or an epoxy group, and most preferably a (meth) acryloyl group.

Examples of the monomer having three or more polymerizable functional groups in one molecule include esters of polyhydric alcohol and (meth) acrylic acid. Specifically, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipenta Examples include erythritol tetra (meth) acrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, pentaerythritol hexa (meth) acrylate, etc., but in terms of high crosslinking, pentaerythritol triacrylate, pentaerythritol tetraacrylate, or dipentaerythritol. Pentaacrylate, dipentaerythritol hexaacrylate, or mixtures thereof are preferred. .

The film thickness of the scratch-resistant layer is preferably from 0.1 μm to 1.5 μm.

(Other additives)
The scratch-resistant layer may contain components other than those described above, and may contain, for example, inorganic particles, a leveling agent, an antifouling agent, an antistatic agent, a surface modifier, a polymerization initiator, and the like.

(Abrasion resistance)
In the scratch resistance test in which the surface is scratched with steel wool applied with a load of 1000 g / cm ² , the scratch resistance layer is preferably 100 or more reciprocations until the scratches that can be visually observed are generated. More preferably, it is more preferably 10,000 reciprocations or more.

Hereinafter, the present invention will be described more specifically by way of examples. However, the scope of the present invention should not be construed as being limited thereto.

[Production of substrate]
(Manufacture of polyimide powder)
Under a nitrogen stream, 832 g of N, N-dimethylacetamide (DMAc) was added to a 1 L reactor equipped with a stirrer, a nitrogen injection device, a dropping funnel, a temperature controller and a condenser, and then the temperature of the reactor was adjusted to 25. C. To this, 64.046 g (0.2 mol) of bistrifluoromethylbenzidine (TFDB) was added and dissolved. While maintaining the resulting solution at 25 ° C., 31.09 g (0.07 mol) of 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and biphenyltetracarboxylic dianhydride The product (BPDA) 8.83 g (0.03 mol) was added, and the mixture was stirred for a certain time to be reacted. Thereafter, 20.302 g (0.1 mol) of terephthaloyl chloride (TPC) was added to obtain a polyamic acid solution having a solid concentration of 13% by mass. Next, 25.6 g of pyridine and 33.1 g of acetic anhydride were added to this polyamic acid solution, stirred for 30 minutes, further stirred at 70 ° C. for 1 hour, and then cooled to room temperature. 20 L of methanol was added thereto, and the precipitated solid was filtered and pulverized. Then, it was made to dry in vacuum at 100 degreeC for 6 hours, and 111 g of polyimide powder was obtained.

[Production of Substrate S-1]
100 g of polyimide powder was dissolved in 670 g of N, N-dimethylacetamide (DMAc) to obtain a 13% by mass solution. The obtained solution was cast on a stainless steel plate and dried with hot air at 130 ° C. for 30 minutes. After that, the film is peeled off from the stainless steel plate and fixed to the frame with a pin. The frame on which the film is fixed is put into a vacuum oven and heated for 2 hours while gradually increasing the heating temperature from 100 ° C to 300 ° C. Cooled to. After the cooled film was separated from the frame, as a final heat treatment step, it was further heat treated at 300 ° C. for 30 minutes to obtain a substrate S-1 made of polyimide film and having a thickness of 30 μm.

[Synthesis of silane coupling agent]
(Synthesis of silane coupling agent C-1)
To a flask equipped with a reflux condenser and a thermometer, 13.6 g of Shin-Etsu Chemical KBE-9007, 16.4 g of pentaerythritol triacrylate, 0.1 g of dibutyltin dilaurate and 70.0 g of toluene were added, and 12 hours at room temperature. Stir. After stirring, 500 ppm of methylhydroquinone (parts per million) was added and distilled off under reduced pressure to obtain a silane coupling agent C-1 represented by the structural formula (1).

[Synthesis of Silane Coupling Agent C-2]
To a flask equipped with a reflux condenser and a thermometer, 9.1 g of Shin-Etsu Chemical KBE-9007, 20.9 g of dipentaerythritol pentaacrylate, 0.1 g of dibutyltin dilaurate and 70.0 g of toluene were added, and 12 hours at room temperature. Stir. After stirring, the mixture was distilled off under reduced pressure to obtain a silane coupling agent C-2 represented by the structural formula (2).

[Preparation of silica particles]
(Preparation of silica particles P-1)
A reactor having a capacity of 200 L equipped with a stirrer, a dropping device and a thermometer was charged with 89.46 kg of pure water and 0.10 kg of 28% by mass ammonia water, and the liquid temperature was adjusted to 90 ° C. while stirring. While maintaining the liquid temperature in the reactor at 90 ° C., 10.44 kg of tetramethoxysilane was dropped from the dropping device over 102 minutes, and after completion of the dropping, the liquid temperature was further stirred for 120 minutes while maintaining the above temperature. As a result, hydrolysis and condensation of tetramethoxysilane were carried out. The obtained colloid solution was concentrated to 38.8 kg under a reduced pressure of 13.3 kPa using a rotary evaporator to obtain silica particles P-1 having a SiO ₂ concentration of 10.0% by mass. The average primary particle size of silica particles P-1 was 5 nm.

(Preparation of silica particles P-2)
Silica particles P-2 were obtained in the same manner as silica particles P-1, except that tetramethoxysilane was added dropwise over 114 minutes. The average primary particle size of the silica particles P-2 was 15 nm.

(Preparation of silica particles P-3)
Silica particles P-3 were obtained in the same manner as silica particles P-1, except that tetramethoxysilane was added dropwise over 156 minutes. The average primary particle size of the silica particles P-3 was 50 nm.

(Preparation of silica particles P-4)
Silica particles P-4 were obtained in the same manner as silica particles P-1, except that tetramethoxysilane was added dropwise over 240 minutes. The average primary particle size of silica particles P-4 was 120 nm.

(Preparation of silica particles P-13)
Silica particles P-13 were obtained in the same manner as silica particles P-1, except that tetramethoxysilane was added dropwise over 216 minutes. The average primary particle size of silica particles P-13 was 100 nm.

(Preparation of silica particles P-5)
300 g of silica particles P-1 were charged into a 1 L glass reactor equipped with a stirrer. A solution prepared by dissolving 6.75 g of 3-methacryloxypropyltrimethoxysilane (KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.) in 20 g of methyl alcohol was added dropwise thereto and mixed. Thereafter, heat treatment was performed at 95 ° C. for about 2 hours with mixing and stirring. After cooling, 100 g of 1-methoxy-2-propanol was added, and by-product methanol was distilled off under reduced pressure. Further, 300 g of 1-methoxy-2-propanol was added in several portions, and water was distilled off under reduced pressure by azeotropic distillation so that the solid content was 60% by mass to obtain silica particles P-5. In addition, solid content heated for 30 minutes at 150 degreeC, and computed from the weight change before and behind.

(Preparation of silica particles P-6)
Silica particle P-6 was obtained in the same manner as silica particle P-5, except that silica particle P-1 was changed to silica particle P-2 and 3-methacryloxypropyltrimethoxysilane was changed to 2.25 g.

(Preparation of silica particles P-7)
Silica particles P-7 were obtained in the same manner as silica particles P-5 except that silica particles P-1 were changed to silica particles P-3 and 3-methacryloxypropyltrimethoxysilane was changed to 0.68 g.

(Preparation of silica particles P-8)
Silica particle P-8 was obtained in the same manner as silica particle P-5, except that silica particle P-1 was changed to silica particle P-4 and 3-methacryloxypropyltrimethoxysilane was changed to 0.28 g.

(Preparation of silica particles P-14)
Silica particles P-14 were obtained in the same manner as silica particles P-5 except that silica particles P-1 were changed to silica particles P-13 and 3-methacryloxypropyltrimethoxysilane was changed to 0.34 g.

(Preparation of silica particles P-9)
Silica particle P-9 was obtained in the same manner as silica particle P-5, except that 3-methacryloxypropyltrimethoxysilane (6.75 g) was changed to silane coupling agent C-1 (13.7 g). .

(Preparation of silica particles P-10)
Silica particles P-5 were changed to silica particles P-2, and 3-methacryloxypropyltrimethoxysilane (6.75 g) was changed to silane coupling agent C-1 (4.6 g). Silica particles P-10 were obtained in the same manner.

(Preparation of silica particles P-11)
The silica particles P-5 and silica particles P-5 were used except that the silica particles P-1 were changed to silica particles P-2 and 3-methacryloxypropyltrimethoxysilane (6.75 g) was changed to silane coupling agent C-2 (6.6 g). Silica particles P-11 were obtained in the same manner.

(Preparation of silica particles P-12)
1-Methoxy-2-propanol (100 g) was added to silica particle P-2 (300 g), and by-product methanol was distilled off under reduced pressure. Further, 1-methoxy-2-propanol (300 g) was added in several portions, and water was distilled off under reduced pressure by azeotropic distillation so that the solid content was 60% by mass to obtain silica particles P-12.

[Preparation of hard coat film]
(Preparation of hard coat layer forming coating solution)
Coating components HC-1 to HC-20 for forming a hard coat layer were prepared by mixing each component with the composition (mass%) shown in Table 1 and Table 2 below. The composition of the silica particles is a value as a dispersion having a solid content of 60% by mass.

A-400: Polyethylene glycol # 400 diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
A-200: Polyethylene glycol # 200 diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
A-1000: Polyethylene glycol # 1000 diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
DPCA-120: caprolactone-modified dipentaerythritol hexaacrylate, trade name KAYARAD DPCA-120 (manufactured by Nippon Kayaku Co., Ltd.)
DPCA-60: caprolactone-modified dipentaerythritol hexaacrylate, trade name KAYARAD DPCA-60 (manufactured by Nippon Kayaku Co., Ltd.)
DPCA-20: Caprolactone-modified dipentaerythritol hexaacrylate, trade name KAYARAD DPCA-20 (manufactured by Nippon Kayaku Co., Ltd.)
DPHA: Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)
DCP-A: dimethylol-tricyclodecane diacrylate, trade name light acrylate DCP-A (manufactured by Kyoei Chemical Co., Ltd.)
UA-33H: Urethane acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
A-DPH-6E: ethylene oxide adduct of dipentaerythritol hexaacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)
Irgacure 184: Photopolymerization initiator (manufactured by BASF)

(Preparation of hard coat film A)
The coating liquid HC-1 for forming a hard coat layer was applied onto the substrate S-1 using a gravure coater so that the thickness after curing was 17 μm. After drying at 100 ° C., an ultraviolet ray with an irradiation amount of 300 mJ / cm ² using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 100 ppm or less. Was applied to cure the coating layer, a hard coat layer was formed, and a hard coat film A was produced.

(Preparation of hard coat films BT)
Hard coat films BT were produced in the same manner as hard coat film A, except that coating liquids HC-2 to 20 were used instead of coating liquid HC-1.

[Evaluation of hard coat film]
The produced hard coat film was evaluated by the following methods.

(Indentation modulus)
HM2000 hardness tester (Fischer Instruments, Knoop indenter made of diamond) is used for the hard coat layer surface of each hard coat film, and the maximum indentation depth is 0.34 μm (2% with respect to the thickness of the hard coat layer). The maximum load was adjusted so as to be 1.7 μm (10%), and an indentation test was performed under the conditions of an indentation speed of 10 seconds and a creep of 5 seconds, and the indentation elastic modulus at each indentation depth was obtained.

(Inorganic fine particle volume ratio of hard coat layer)
The surface of the hard coat film was scraped off with a scraper, 10 g or more of the hard coat layer was recovered, and the mass was measured. The recovered hard coat layer was heated at 600 ° C. for 3 hours in an air atmosphere, the matrix components were burned to recover inorganic fine particles, and the mass was measured. The specific gravity of the matrix component was 1.2, the specific gravity of the silica particles was 2.2, and the inorganic fine particle volume ratio in the hard coat layer was determined.

(Pencil hardness)
It was measured according to JIS K 5600-5-4 (1999).

(Bend resistance (repeated bending resistance) evaluation)
A sample film having a width of 15 mm and a length of 150 mm was cut out from the hard coat film and allowed to stand for 1 hour or longer in a state of a temperature of 25 ° C. and a relative humidity of 65%. After that, using a bending resistance tester (Imoto Seisakusho Co., Ltd., model IMC-0755, bending radius 1.0 mm), repeated bending resistance tests were performed with the hard coat layer side facing the bending inner side. It was. The number of times until the sample film was cracked or broken was evaluated according to the following criteria.
A: 1 million times or more B: 800,000 times or more, less than 1 million times C: 500,000 times or more, less than 800,000 times D: 100,000 times or more, less than 500,000 times E: Less than 100,000 times

(Indentation modulus of matrix component)
For each hard coat layer forming coating solution, a matrix layer forming composition prepared without adding silica particles was prepared, and the matrix layer was formed on the substrate S-1 by the same method as the hard coat layer. Formed. The coating amount was adjusted so that the thickness of the matrix layer was 17 μm. Except that the maximum load was adjusted so that the maximum indentation depth was 0.34 μm (2% with respect to the thickness of the matrix layer) on the surface of the matrix layer, the same indentation test as the hard coat films A to T was performed. the indentation modulus E _M of matrix components was determined. The evaluation results are shown in Tables 3 and 4 below.

[Preparation of scratch-resistant hard coat film]
(Preparation of hard coat film A-2)
A coating liquid HC-1 for forming a hard coat layer was applied on the substrate S-1 using a gravure coater so that the thickness after curing was 17 μm. After drying at 100 ° C., using a 20 W / cm air-cooled metal halide lamp (made by Eye Graphics Co., Ltd.) while purging with nitrogen so that the atmosphere has an oxygen concentration of 1.5% or less, the irradiation dose is 20 mJ / cm. ^The coating layer was cured by irradiating the ultraviolet ray ² to form a hard coat layer, and a hard coat film A-2 was produced.

(Preparation of scratch-resistant coating solution)
Each component was mixed in the composition (mass%) shown in Table 5 below to prepare scratch-resistant layer forming coating solutions SC-1 and SC-2.

Irgacure 127: Polymerization initiator (BASF)
RS-90: Surface modifier, trade name MegaFac RS-90 (manufactured by DIC Corporation)

(Preparation of hard coat film U with scratch-resistant layer)
On the hard coat layer of the hard coat film A-2, the scratch-resistant layer forming coating solution SC-1 was applied using a gravure coater so that the thickness after curing was 0.1 μm and dried at 100 ° C. . Thereafter, using an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) of 160 mW / cm ² while purging with nitrogen so that the oxygen concentration becomes 100 ppm or less on an 80 ° C. hot plate, the irradiation amount is 1200 mJ / cm. A hard coat film U with a scratch-resistant layer was prepared by irradiating and curing the ultraviolet ray ² from the coating film side.

(Preparation of hard coat film V with scratch-resistant layer)
A hard coat film V with a scratch-resistant layer was prepared in the same manner as the hard coat film U with a scratch-resistant layer except that the coating solution for forming the scratch-resistant layer was changed to SC-2 and the thickness after curing was changed to 1.0 μm. did.

[Evaluation of Hard Coat Film with Scratch Resistant Layer]
The produced hard coat film with a scratch-resistant layer was evaluated by the following methods.

(Abrasion resistance)
The surface of the scratch-resistant layer of the hard coat film with the scratch-resistant layer was subjected to a rubbing test using a rubbing tester under the following conditions, and used as an index of scratch resistance.
Evaluation environmental conditions: 25 ° C., relative humidity 60%
Rubbing material: Steel wool (manufactured by Nippon Steel Wool Co., Ltd., Grade No. 0000)
Wrap around the tip (1 cm x 1 cm) of the tester that comes into contact with the sample. Band fixing Movement distance (one way): 13 cm,
Rubbing speed: 13 cm / second,
Load: 1000 g / cm ²
Tip contact area: 1 cm × 1 cm,
The number of rubs: 100 reciprocations, 10000 reciprocations The oily black ink was applied to the back of the rubbed sample, and the scratches on the rubbed portions were evaluated by visual observation with reflected light.
A: Even if you look very carefully, no scratches are visible.
B: If you look carefully, you can see weak scratches, but it doesn't matter. C: There are scratches that can be seen at first glance, and are very conspicuous.

Evaluation results are shown in Table 6 below.

As shown in Tables 3 and 4, the hard coat films of the examples were excellent in both hardness and repeated bending resistance. On the other hand, the hard coat films of Comparative Examples 1 to 6 and 9 have an E ₂ greater than 8 GPa and poor repeated bending resistance, and the hard coat films of Comparative Examples 7, 8, and ₁₁ have an E ₁₀ of less than 8 GPa. Pencil hardness was inferior. Moreover, since the average primary particle diameter of the hard coat film of Comparative Example 10 was larger than 100 nm, both the pencil hardness and the repeated bending resistance were inferior. Further, as shown in Table 6, Examples 10 and 11 provided with the scratch-resistant layer were excellent in hardness, repeated bendability, and scratch resistance.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application filed on March 9, 2018 (Japanese Patent Application No. 2018-43373) and a Japanese patent application filed on September 28, 2018 (Japanese Patent Application No. 2018-185805). Is incorporated herein by reference.

Claims

A hard coat film having a hard coat layer on at least one surface of a support,
The hard coat layer includes a matrix component and inorganic fine particles having an average primary particle size of 3 to 100 nm;
The content of the inorganic fine particles in the hard coat layer is 50% by volume or more and 90% by volume or less,
Indentation when the hard coat layer is indented 10% with respect to the thickness of the hard coat layer in an indentation test in which a load is applied vertically from the surface opposite to the support side using a diamond knoop indenter. When the elastic modulus is E 10 and the indentation elastic modulus when indented by 2% with respect to the thickness of the hard coat layer is E 2 , the following formulas (1), (2), and (3) are satisfied. A hard coat film.
E 10 −E 2 ≧ 2 GPa (1)
E 10 ≧ 8 GPa (2)
E 2 ≦ 8 GPa (3)
The hard coat film according to claim 1, wherein E M ≦ 1.5 GPa when the indentation elastic modulus of the matrix component is E M.
The matrix component is a cured product of the matrix-forming composition;
The hard coat film according to claim 1 or 2, wherein the polymerizable functional group equivalent in the matrix-forming composition is 250 or more.
The hard coat film according to any one of claims 1 to 3, wherein the inorganic fine particles are particles modified with a silane coupling agent having two or more polymerizable functional groups in one molecule.
The support is selected from triacetylcellulose film, polymethylmethacrylate film, polyamide film, aramid film, polyimide film, polyamideimide film, polyetherimide film, polyesterimide film, and polyethylene terephthalate film. 5. The hard coat film according to any one of 4 above.
A hard coat film with a scratch-resistant layer having a scratch-resistant layer on a surface of the hard coat film according to any one of claims 1 to 5 opposite to the support side of the hard coat layer.