JP2014040037A - Hard coat film, transparent conductive film, and touch panel - Google Patents

Abstract

【Task】
Provided is a hard coat film having good wet-heat adhesion of a hard coat layer, high transmittance, and good slipperiness and blocking resistance. Moreover, the transparent conductive film which used this hard coat film as a base film, and the touch panel using this transparent conductive film are provided.
[Solution]
At least one surface of the polyester film has a first resin layer composed of two or more resin layers and a first hard coat layer in this order, and the first resin layer has a polyester resin in order from the polyester film side. A hard coat film comprising at least a resin layer 1A having a main component and a resin layer 1B having an acrylic resin as a main component, wherein the first hard coat layer contains organic particles having an average particle diameter of 500 nm or less. .
[Selection figure] None

Description

  The present invention relates to a hard coat film, and more particularly to a hard coat film suitable as a base film of a transparent conductive film. Specifically, the hard coat layer has excellent wet heat adhesion, good slipperiness and blocking resistance, high transmittance hard coat film, and transparent conductive layer having a transparent conductive layer laminated on at least one surface of the hard coat film. The present invention relates to a conductive film and a touch panel using the transparent conductive film.

  It is known that the hard coat film is used for screen protection of a display device and used as a base film of a transparent conductive film for electrode formation of a touch panel (Patent Documents 1 to 6). That is, these patent documents disclose a transparent conductive film for a touch panel in which a transparent conductive layer is laminated on at least one surface of a hard coat film.

In addition, it is known that organic particles (resin particles) are contained in the hard coat layer in order to improve the slipping property and blocking resistance of the hard coat film and prevent New Ring (Patent Documents 7 to 11). )
On the other hand, it is known to provide an easy-adhesion layer (primer layer) between the base film and the hard coat layer in order to improve the adhesion between the base film and the hard coat layer (Patent Documents 12 to 12). 15).

JP 2005-209431 A JP 2010-188540 A JP 2011-39978 A JP2011-65937A JP 2011-145593 A JP 2011-175040 A JP 2007-238732 A JP 2010-231540 A JP 2011-68064 A JP 2011-201087 A JP 2011-202072 A Japanese Patent Laid-Open No. 08-244186 JP 2000-246856 A JP 2004-299101 A JP 2012-51242 A

  As described above, in order to improve the slipperiness and blocking resistance of the hard coat film, it is known to contain particles in the hard coat layer. Inorganic particles generally have a large refractive index difference from the resin constituting the hard coat layer, so that light scattering inside the hard coat layer increases and the transmittance may decrease. On the other hand, the organic particles generally have a small difference in refractive index from the resin constituting the hard coat layer, so that light scattering inside the hard coat layer is small, and a decrease in transmittance is suppressed.

  On the other hand, in recent years, high performance is required for a display device equipped with a touch panel, and accordingly, high performance is also required for a transparent conductive film for a touch panel and a hard coat film used as a base film thereof. For example, high transmittance, neutral and colorless reflection color, good slipping property, blocking resistance, adhesion and the like are required.

  In particular, the adhesiveness is required to have good adhesiveness (wet heat adhesiveness) when stored for a long time under high temperature and high humidity conditions.

  The hard coat layer containing organic particles is advantageous from the viewpoint of realizing high transmittance as described above, but wet heat adhesion tends to decrease.

  Moreover, the hard coat film used as the base film of the transparent conductive film for touch panel is required to have high transmittance, good slipping property and blocking resistance as described above. When the blocking resistance is improved, the transmittance tends to decrease.

  Accordingly, an object of the present invention is to provide a hard coat film in which the wet heat adhesion of the hard coat layer is good, the transmittance is high, and the slipperiness and blocking resistance are good. Furthermore, an object of the present invention is to provide a transparent conductive film using the hard coat film of the present invention as a base film, and a touch panel using the transparent conductive film.

The above object of the present invention has been basically achieved by the following invention.
(1) At least one surface of the polyester film has a first resin layer composed of two or more resin layers and a first hard coat layer in this order, and the first resin layer is in order from the polyester film side. Including at least a resin layer 1A having a polyester resin as a main component and a resin layer 1B having an acrylic resin as a main component, wherein the first hard coat layer contains organic particles having an average particle diameter of 500 nm or less, Hard coat film.
(2) The refractive index (nf) of the polyester film is 1.62-1.70, the refractive index (n1a) of the resin layer 1A is 1.55 to 1.61, and the refractive index (n1b) of the resin layer 1B. The hard coat film according to (1), wherein 1.48 to 1.54 and the refractive index (n1h) of the first hard coat layer is 1.48 to 1.54.
(3) The hard coat film according to (1) or (2), wherein the organic particles are acrylic resin particles.
(4) The hard coat film according to any one of (1) to (3), wherein a center line average roughness Ra (Ra1) of the surface of the first hard coat layer is 5 to 30 nm.
(5) The second resin layer and the second hard coat layer constituted by two or more resin layers are provided on the opposite surface of the polyester film from the surface on which the first resin layer and the first hard coat layer are provided. In order, the second resin layer includes at least a resin layer 2A mainly composed of a polyester resin and a resin layer 2B mainly composed of an acrylic resin in order from the polyester film side (1) to (4) The hard coat film according to any one of the above.
(6) The refractive index (nf) of the polyester film is 1.62-1.70, the refractive index (n2a) of the resin layer 2A of the second resin layer is 1.55 to 1.61, and the resin layer 2B is The hard coat film according to (5), wherein the refractive index (n2b) is 1.48 to 1.54, and the refractive index (n2h) of the second hard coat layer is 1.48 to 1.54.
(7) The center line average roughness Ra (Ra2) of the surface of the second hard coat layer is 25 nm or less, and the center line average roughness Ra (Ra1) of the surface of the first hard coat layer and the second hard The hard coat film according to (5) or (6), wherein the difference (Ra1-Ra2) from the center line average roughness Ra (Ra2) of the surface of the coat layer is 3 nm or more.
(8) A transparent conductive film having a transparent conductive layer on at least one surface of the hard coat film according to any one of (1) to (7).
(9) Between the hard coat film and the transparent conductive layer, a high refractive index layer having a refractive index (n1) in the range of 1.60 to 1.80 as a refractive index adjusting layer and a refractive index (n2). The total of the optical thickness (nm) of the high refractive index layer and the low refractive index layer is (1/4). The transparent conductive film according to (8), which satisfies λ (nm). However, (lambda) is 380-780 (nm).
(10) A touch panel comprising the transparent conductive film according to (8) or (9) as a constituent member of the touch panel.

  According to the present invention, it is possible to provide a hard coat film having good wet heat adhesion, high transmittance, and good slipperiness and blocking resistance. The hard coat film of the present invention having such characteristics is suitable for a transparent conductive film. In particular, the hard coat film of the present invention is suitable for a transparent conductive film for a touch panel.

  According to a preferred embodiment of the present invention, it is possible to provide a hard coat film having a neutral and colorless reflection color. Such a hard coat film having a neutral and colorless reflection color is suitable for a transparent conductive film, and particularly suitable for a transparent conductive film for a touch panel.

  The hard coat film of the present invention has a first resin layer composed of two or more resin layers and a first hard coat layer in this order on at least one surface of the polyester film.

  The first resin layer includes at least a resin layer 1A mainly containing a polyester resin and a resin layer 1B mainly containing an acrylic resin from the polyester film side.

  And it has the 1st hard-coat layer containing an organic particle with an average particle diameter of 500 nm or less on a 1st resin layer.

  When the first hard coat layer contains organic particles having an average particle diameter of 500 nm or less, the slipperiness and blocking resistance are improved without decreasing the transparency. When the first hard coat layer contains organic particles, wet heat adhesion tends to decrease. Between the polyester film and the first hard coat layer, a resin layer 1A containing a polyester resin as a main component in this order from the polyester film side. By interposing the first resin layer including the resin layer 1B containing acrylic resin as a main component, the wet heat adhesion of the first hard coat layer is improved.

  The resin layer 1A constituting the first resin layer is preferably provided so as to be in direct contact with the polyester film, and further, the first hard coat layer is provided so as to be in direct contact with the resin layer 1B constituting the first resin layer. It is preferable to provide it.

  The resin layer 1A constituting the first resin layer improves the wet heat adhesion between the polyester film and the first resin layer, and the resin layer 1B improves the wet heat adhesion between the first resin layer and the first hard coat layer. It has a function.

  In the present invention, the refractive index (nf) of the polyester film is in the range of 1.62 to 1.70, the refractive index (n1a) of the resin layer 1A is in the range of 1.55 to 1.61, and the refractive index of the resin layer 1B ( It is preferable that n1b) is in the range of 1.48 to 1.54, and the refractive index (n1h) of the first hard coat layer is in the range of 1.48 to 1.54. Thereby, the transmittance can be further increased, and the reflection color of the first hard coat layer can be made close to neutral colorlessness.

[Polyester film]
The polyester film according to the present invention is a general term for a film made of a polymer compound having an ester bond as a main bond chain, and examples thereof include ethylene terephthalate, propylene terephthalate, and ethylene-2,6-naphthalate. , A film having at least one selected from butylene terephthalate, ethylene-α, β-bis (2-chlorophenoxy) ethane-4,4′-dicarboxylate as a main constituent. Among these films, a polyethylene terephthalate film is particularly preferable from a comprehensive viewpoint such as quality and economy.

  The refractive index (nf) of the polyester film used in the present invention is preferably in the range of 1.62 to 1.70, more preferably in the range of 1.63 to 1.69, and particularly preferably in the range of 1.63 to 1.68. preferable. In particular, a polyethylene terephthalate film having a refractive index (nf) in the range of 1.63 to 1.68 is preferable. In order to set the refractive index (nf) of the polyester film within the above numerical range, a method of biaxially stretching a polyester sheet as described in detail below can be given. When the biaxial stretching method is adopted, generally, the refractive index of the polyester film can be increased by increasing the stretching ratio or lowering the stretching temperature.

  The thickness of the polyester film is preferably in the range of 20 to 300 μm, more preferably in the range of 30 to 250 μm, and particularly preferably in the range of 50 to 200 μm.

[First resin layer]
The first resin layer is provided on at least one surface of the polyester film. The first resin layer may be provided only on one side of the polyester film, or may be provided on both sides of the polyester film. The first resin layer is preferably provided so as to be in direct contact with the polyester film.

  The first resin layer is composed of two or more resin layers and includes, in order from the polyester film side, at least a resin layer 1A mainly composed of a polyester resin and a resin layer 1B mainly composed of an acrylic resin. The first resin layer can include another resin layer (intermediate resin layer) between the resin layer 1A and the resin layer 1B. For example, an intermediate resin layer containing a polyester resin and an acrylic resin may be present between the resin layer 1A and the resin layer 1B.

  The refractive index (n1a) of the resin layer 1A is preferably in the range of 1.55 to 1.61, more preferably in the range of 1.56 to 1.60, and particularly preferably in the range of 1.57 to 1.59. The refractive index (n1b) of the resin layer 1B is preferably in the range of 1.48 to 1.54, more preferably in the range of 1.50 to 1.54, and particularly preferably in the range of 1.51 to 1.54. By setting the refractive indexes of the resin layer 1A and the resin layer 1B in the above ranges, the transmittance of the hard coat film can be further increased, and the reflection color of the first hard coat layer can be neutral and colorless. You can get closer.

  The total thickness of the first resin layer is preferably 0.05 μm or more, more preferably 0.06 μm or more, and particularly preferably 0.07 μm or more from the viewpoint of improving wet heat adhesion between the polyester film and the first hard coat layer. The upper limit thickness is preferably less than 0.5 μm, more preferably 0.4 μm or less, and particularly preferably 0.3 μm or less. When the total thickness of the first resin layer is 0.5 μm or more, there may be a problem that the wet heat adhesion of the first hard coat layer is lowered or the hardness of the first hard coat layer is lowered.

  In addition, the ratio of the thickness of the resin layer 1A to the total thickness of the first resin layer is based on 100% of the total thickness of the first resin layer from the viewpoint of improving wet heat adhesion between the polyester film and the first hard coat layer. The range of 50 to 95% is preferable, and the range of 60 to 90% is more preferable. Similarly, the ratio of the thickness of the resin layer 1B to the total thickness of the first resin layer is preferably in the range of 5 to 50% and more preferably in the range of 10 to 40% with respect to 100% of the total thickness of the first resin layer.

[Resin layer 1A]
The resin layer 1A has a polyester resin as a main component. Here, having a polyester resin as a main component means that the polyester resin is contained in an amount of 50% by mass or more with respect to 100% by mass of the total solid content of the resin layer 1A. Furthermore, the resin layer 1A preferably contains 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more of the polyester resin with respect to 100% by mass of the total solid content of the resin layer 1A. preferable. The upper limit is preferably 99% by mass or less, more preferably 97% by mass or less, and particularly preferably 95% by mass or less.

  The polyester resin has an ester bond in the main chain or side chain, and is generally obtained by polycondensation of a polyvalent carboxylic acid component and a diol component.

  Examples of the polyvalent carboxylic acid component include terephthalic acid, isophthalic acid, orthophthalic acid, phthalic acid, 2,5-dimethylterephthalic acid, 5-sodium sulfoisophthalic acid, 1,4-naphthalenedicarboxylic acid, and 2,6-naphthalene. Dicarboxylic acid, biphenyldicarboxylic acid, 1,2-bisphenoxyethane-p, p'-dicarboxylic acid, phenylindanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, 1,3-cyclopentane Dicarboxylic acids (divalent carboxylic acids) such as dicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, 4- Methylcyclohexene-1,2,3-tricarboxylic acid, tri Sinic acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,3,4-pentanetetracarboxylic acid, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, 5- (2,5 -Dioxotetrahydrofurfuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid, 5- (2,5-dioxotetrahydrofurfuryl-3-cyclohexene-1,2-dicarboxylic acid, cyclopentanetetra Carboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, ethylene glycol bistrimellitate, 2,2 ′, 3,3′-diphenyltetracarboxylic acid, Examples thereof include trivalent or higher polyvalent carboxylic acids such as thiophene-2,3,4,5-tetracarboxylic acid and ethylenetetracarboxylic acid.

  Examples of the diol component include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1, 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 2,4-dimethyl-2-ethylhexane-1,3-diol, Neopentyl glycol, 2-ethyl-2-butyl-1,3-propanediol, 2-ethyl-2-isobutyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2,4 -Trimethyl-1,6-hexanediol, 1,2-cyclohexanedi Tanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 4,4′-thiodiphenol, bisphenol A, 4, 4'-methylenediphenol, 4,4 '-(2-norbornylidene) diphenol, 4,4'-dihydroxybiphenol, o-, m-, and p-dihydroxybenzene, 4,4'-isopropylidenephenol, 4 , 4′-isopropylidenevindiol, cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, and the like.

  Furthermore, in order to facilitate water-solubilization or water-dispersion of the polyester resin, the above-described trivalent or higher polyvalent carboxylic acids and dicarboxylic acids having a sulfo group (for example, sulfoterephthalic acid, sulfoisophthalic acid, 4-sulfonaphthalene- 2,7-dicarboxylic acid or the like) is preferably used, and a polyester resin having a hydrophilic group (carboxyl group or sulfo group) in the side chain is preferably used.

  As described above, the refractive index (n1a) of the resin layer 1A is preferably in the range of 1.55 to 1.61, more preferably in the range of 1.56 to 1.60, and in the range of 1.57 to 1.59. Particularly preferred. In order to relatively increase the refractive index (n1a) of the resin layer 1A as described above, it is preferable to use a polyester resin having a condensed aromatic ring in the molecule as the polyester resin. Examples of such condensed aromatic rings include naphthalene rings and fluorene rings.

  A polyester resin having a naphthalene ring in the molecule can be synthesized by using a dicarboxylic acid having a naphthalene ring such as 1,4-naphthalenedicarboxylic acid or 2,6-naphthalenedicarboxylic acid as a polyvalent carboxylic acid component. .

  The polyester resin having a fluorene ring in the molecule can be synthesized by using a compound having a fluorene ring as the polyvalent carboxylic acid component and / or the diol component. The polyester resin which has a fluorene ring in a molecule | numerator is described in detail in the international publication number WO2009 / 145075, for example, It can synthesize | combine with reference to it.

  The thickness of the resin layer 1A is preferably 0.01 μm or more, more preferably 0.02 μm or more, further preferably 0.03 μm or more from the viewpoint of improving wet heat adhesion between the polyester film and the first resin layer. 05 μm or more is preferable. The upper limit thickness is preferably 0.4 μm or less, more preferably 0.3 m or less, and particularly preferably 0.2 μm or less. If the thickness of the resin layer 1A is larger than 0.4 μm, the wet heat adhesion between the polyester film and the first hard coat layer may be lowered.

[Resin layer 1B]
The resin layer 1B has an acrylic resin as a main component. Here, having an acrylic resin as a main component means that the acrylic resin is contained in an amount of 50% by mass or more with respect to 100% by mass of the total solid content of the resin layer 1B. Furthermore, the resin layer 1B preferably contains 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more, with respect to 100% by mass of the total solid content of the resin layer 1B. preferable. The upper limit is preferably 99% by mass or less, more preferably 97% by mass or less, and particularly preferably 95% by mass or less.

  As an acrylic resin, the monomer illustrated below can be superposed | polymerized using 1 type, or 2 or more types, for example. In the following description, the expression “... (Meth) acrylate” includes two compounds “... acrylate” and “... methacrylate”. The expression “acrylamide” includes two compounds, “... acrylamide” and “... methacrylamide”.

  Examples of the monomer include alkyl (meth) acrylate (the alkyl group is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, 2-ethylhexyl, lauryl) Group, stearyl group, cyclohexyl group, phenyl group, benzyl group, phenylethyl group, etc.), hydroxy group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) acrylamide, N Amide group-containing monomers such as methyl (meth) acrylamide, N-methylol (meth) acrylamide, N, N-dimethylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-phenyl (meth) acrylamide, N-diethylaminoethyl Carboxyl groups such as amino group-containing monomers such as (meth) acrylate, epoxy group-containing monomers such as glycidyl (meth) acrylate, (meth) acrylic acid and salts thereof (lithium salts, sodium salts, potassium salts, etc.) or salts thereof And the like.

  Further, the acrylic resin can be contained as a copolymerization component with other monomers other than the above monomers.

  Other monomers include, for example, epoxy group-containing monomers such as allyl glycidyl ether, sulfonic acid groups such as styrene sulfonic acid, vinyl sulfonic acid and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.) or its Monomers containing a carboxyl group such as a salt-containing monomer, crotonic acid, itaconic acid, maleic acid, fumaric acid and salts thereof (lithium salt, sodium salt, potassium salt, ammonium salt, etc.) or a salt thereof, maleic anhydride , Monomers containing acid anhydrides such as itaconic anhydride, vinyl isocyanate, allyl isocyanate, styrene, vinyl methyl ether, vinyl ethyl ether, vinyl trisalkoxysilane, alkyl maleic acid monoester, alkyl fumaric acid monoester, acrylic Nitrile, methacrylonitrile, alkyl itaconic acid monoester, vinylidene chloride, vinyl acetate, vinyl chloride and the like.

  The acrylic resin is preferably water-soluble, water-dispersible, or emulsifiable. The water-soluble or water-dispersible acrylic resin is obtained by introducing a carboxylic acid group or a sulfonic acid group into the molecule. The emulsifying acrylic resin can be obtained by emulsion polymerization.

  As described above, the refractive index (n1b) of the resin layer 1B is preferably in the range of 1.48 to 1.54, more preferably in the range of 1.50 to 1.54, and in the range of 1.51 to 1.54. Particularly preferred. The resin layer 1B is a resin layer containing an acrylic resin as a main component, and the refractive index of the resin layer 1B can be within the above range by synthesizing this acrylic resin with the above-described monomer.

  The thickness of the resin layer 1B is preferably 0.005 μm or more, and more preferably 0.01 μm or more from the viewpoint of improving the adhesion between the first resin layer and the first hard coat layer. The upper limit thickness is preferably 0.2 μm or less, more preferably 0.1 μm or less, and particularly preferably 0.05 μm or less. When the thickness of the resin layer 1B is larger than 0.2 μm, the wet heat adhesion between the first resin layer and the first hard coat layer may be lowered.

[Other components of the first resin layer]
The first resin layer preferably contains a crosslinking agent. The first resin layer is preferably a thermosetting resin layer containing a crosslinking agent. When the first resin layer contains a crosslinking agent, wet heat adhesion between the polyester film and the first hard coat layer is improved.

  The crosslinking agent is preferably contained in at least one resin layer constituting the first resin layer, preferably contained in at least the resin layer 1A constituting the first resin layer, and at least the resin constituting the first resin layer. It is particularly preferable to contain it in the layer 1A and the resin layer 1B.

  At least one layer constituting the first resin layer is preferably a thermosetting resin layer containing a crosslinking agent, and at least the resin layer 1A constituting the first resin layer is a thermosetting resin layer containing a crosslinking agent. It is preferable that at least the resin layer 1A and the resin layer 1B constituting the first resin layer are thermosetting resin layers containing a crosslinking agent.

  As crosslinking agents, melamine crosslinking agents, oxazoline crosslinking agents, carbodiimide crosslinking agents, isocyanate crosslinking agents, aziridine crosslinking agents, epoxy crosslinking agents, methylolated or alkylolized urea crosslinking agents, acrylamide crosslinking agents Polyamide resins, amide epoxy compounds, various silane coupling agents, various titanate coupling agents, and the like can be used. Among these, melamine-based crosslinking agents, oxazoline-based crosslinking agents, and carbodiimide-based crosslinking agents are preferably used.

  The melamine-based crosslinking agent is not particularly limited, but melamine, a methylolated melamine derivative obtained by condensing melamine and formaldehyde, a compound partially or completely etherified by reacting a methylolated melamine with a lower alcohol, and these A mixture of the above can be used. The melamine-based crosslinking agent may be a monomer, a condensate composed of a dimer or higher polymer, or a mixture thereof. As the lower alcohol used for etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like can be used. The functional group has an imino group, a methylol group, or an alkoxymethyl group such as a methoxymethyl group or a butoxymethyl group in one molecule, and an imino group type methylated melamine resin, a methylol group type melamine resin, or a methylol group type. Examples include methylated melamine resins and fully alkyl type methylated melamine resins. Of these, methylolated melamine resins are most preferred. Further, an acidic catalyst such as p-toluenesulfonic acid may be used in order to accelerate the thermal curing of the melamine-based crosslinking agent.

  The oxazoline-based crosslinking agent is not particularly limited as long as it has an oxazoline group as a functional group in the compound, but includes at least one monomer containing an oxazoline group, and at least one kind of What consists of an oxazoline group containing copolymer obtained by copolymerizing another monomer is preferable.

  Monomers containing an oxazoline group include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-Isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, and the like can be used, and one or a mixture of two or more thereof can also be used. Of these, 2-isopropenyl-2-oxazoline is preferred because it is easily available industrially.

  In the oxazoline-based cross-linking agent, the at least one other monomer used for the monomer containing the oxazoline group is not particularly limited as long as it is a monomer copolymerizable with the monomer containing the oxazoline group. Acrylates or methacrylates such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, acrylate-2-ethylhexyl, methacrylate-2-ethylhexyl, etc. Unsaturated carboxylic acids such as acid, methacrylic acid, itaconic acid and maleic acid, unsaturated nitriles such as acrylonitrile and methacrylonitrile, acrylamide, methacrylamide, N-methylolacrylamide, N-methylol methacrylate Contains unsaturated amides such as amides, vinyl esters such as vinyl acetate and vinyl propionate, vinyl ethers such as methyl vinyl ether and ethyl vinyl ether, olefins such as ethylene and propylene, vinyl chloride, vinylidene chloride and vinyl fluoride. Halogen- [alpha], [beta] -unsaturated monomers, [alpha], [beta] -unsaturated aromatic monomers such as styrene and [alpha] -methylstyrene can be used, and these should be used alone or in a mixture of two or more. You can also.

  The carbodiimide-based crosslinking agent is not particularly limited as long as it is a compound having one or two or more cyanamide groups in the molecule as a functional group in the compound. . Specific examples of such carbodiimide compounds include dicyclohexylmethane carbodiimide, dicyclohexyl carbodiimide, tetramethylxylylene carbodiimide, urea-modified carbodiimide, and the like, and these may be used alone or as a mixture of two or more. .

  The content of the crosslinking agent is preferably in the range of 1 to 40% by mass, more preferably in the range of 3 to 35% by mass, particularly 5 to 30% with respect to 100% by mass of the total solid content of the resin layer containing the crosslinking agent. A range of mass% is preferred.

  The first resin layer preferably further contains particles. Since the 1st resin layer contains particle | grains, since the slidability of the laminated polyester film which laminated | stacked the 1st resin layer on the polyester film improves, it is preferable.

  The particles are preferably contained in at least the resin layer 1A constituting the first resin layer.

  Examples of such particles include inorganic particles (colloidal silica, titanium oxide, aluminum oxide, zirconium oxide, calcium carbonate, carbon black, zeolite particles, etc.) and organic particles (acrylic resin particles, styrene resin particles, polyester resin particles, polyurethane). Resin particles, polycarbonate resin particles, polyamide resin particles, silicone resin particles, fluorine resin particles, or copolymer resin particles of two or more monomers used for the synthesis of the above resin). Among these, colloidal silica is preferably used.

  The average particle diameter of the particles is preferably in the range of 30 to 500 nm, more preferably in the range of 50 to 400 nm, and particularly preferably in the range of 50 to 300 nm.

  The content of the particles is preferably in the range of 0.05 to 8% by mass, more preferably in the range of 0.1 to 5% by mass with respect to 100% by mass of the total solid content of the resin layer containing the particles.

[Method for Forming First Resin Layer]
The first resin layer includes at least a resin layer 1A and a resin layer 1B. Hereinafter, a method of laminating the resin layer 1A and the resin layer 1B will be described. Examples of such methods include the following methods (i) to (iii).
(I) A method of applying and drying a coating liquid for forming the resin layer 1A and a coating liquid for forming the resin layer 1B in this order on the polyester film.
(Ii) A method in which a coating liquid for forming the resin layer 1A and a coating liquid for forming the resin layer 1B are applied simultaneously on the polyester film and dried.
(Iii) On the polyester film, a mixture of the component that forms the resin layer 1A and the component that forms the resin layer 1B is applied, and the resin layer 1A and the resin layer 1B are formed using self-phase separation of each component. how to.

  The application of the above (i) to (iii) is performed in a polyester film manufacturing process, a so-called in-line coating method, a so-called off-line coating method performed in a process separate from the polyester film manufacturing process, and the above in-line coating method. And a method combining the off-line coating method. Among these, the in-line coating method is preferable.

  As a coating method, a wet coating method is preferable, and for example, a reverse coating method, a spray coating method, a bar coating method, a gravure coating method, a rod coating method, a die coating method, and the like can be used, but not limited thereto. Examples of the coating method (wet coating method) used in the simultaneous multilayer coating (ii) above include a multilayer slot die coater, a multilayer slide bead coater, and an extrusion type die coater.

  When forming a 1st resin layer on a polyester film, it is preferable to give a corona discharge process, a flame process, a plasma process etc. to the polyester film surface as a preliminary treatment for improving applicability | paintability and adhesiveness.

  The method (iii) for forming the resin layer 1A and the resin layer 1B using the self-phase separation is preferable in terms of productivity because the first resin layer can be formed by one application.

  When carrying out the method (iii), it is preferable to increase the surface energy difference between the main component (polyester resin) of the resin layer 1A and the main component (acrylic resin) of the resin layer 1B. That is, it is preferable to use a polyester resin having a high surface energy and an acrylic resin having a low surface energy. In particular, it is preferable to use a polyester resin having a sulfonic acid group in order to increase the surface energy of the polyester resin.

  When the method (iii) is performed, a region (mixed region) in which the main component (polyester resin) of the resin layer 1A and the main component (acrylic resin) of the resin layer 1B are mixed between the resin layer 1A and the resin layer 1B. May be formed. The mixed region works in a good direction with respect to the transmittance and reflected color of the hard coat film, but the effect is slight. Therefore, the thickness of the resin layer 1A and the resin layer 1B formed by carrying out the method (iii) is the polyester which is the main component of the resin layer 1A in the total thickness of the first resin layer regardless of the presence or absence of the mixed region. The content ratio (mass ratio) of the resin and the acrylic resin that is the main component of the resin layer 1B is multiplied.

  Regarding the production method for laminating the first resin layer on the polyester film by the in-line coating method, an embodiment using a polyethylene terephthalate (hereinafter abbreviated as PET) film as the polyester film will be described, but the present invention is not limited thereto. Absent.

  PET pellets with an intrinsic viscosity of 0.5 to 0.8 dl / g, which is a raw material for PET film, are vacuum-dried, then supplied to an extruder, melted at 260 to 300 ° C, extruded into a sheet form from a T-shaped die, An unstretched PET film is produced by winding it around a mirror-casting drum having a surface temperature of 10 to 60 ° C. by using an electric application casting method and cooling and solidifying the drum. This unstretched PET film is stretched 2.5 to 5 times in the longitudinal direction (referring to the traveling direction of the film and also referred to as “longitudinal direction”) between rolls heated to 70 to 100 ° C. At least one surface of the uniaxially stretched PET film obtained by this stretching is subjected to corona discharge treatment in the air, the wet tension of the surface is set to 47 mN / m or more, and the first resin layer is formed on the treated surface by the method described above. Apply an aqueous coating solution.

  Next, the uniaxially stretched PET film coated with the aqueous coating solution is gripped with a clip and guided to a drying zone, dried at a temperature lower than Tg of the uniaxially stretched PET film, then raised to a temperature equal to or higher than Tg, and again near Tg. Drying at a temperature, followed by continuous stretching in a heating zone at 70 to 150 ° C. in the transverse direction (referring to a direction perpendicular to the film traveling direction, also referred to as “width direction”) 2.5 to 5 times, followed by 180 Heat treatment is performed in a heating zone of ˜240 ° C. for 5 to 40 seconds to obtain a laminated polyester film in which the first resin layer is laminated on the PET film in which crystal orientation is completed.

  In addition, you may perform a 3-12% relaxation process as needed during the said heat processing. Biaxial stretching may be longitudinal, transverse sequential stretching, or simultaneous biaxial stretching, and may be re-stretched in either the longitudinal or transverse direction after longitudinal and transverse stretching.

[First hard coat layer]
The first hard coat layer is preferably laminated so as to be in direct contact with the first resin layer from the viewpoint of improving wet heat adhesion. Further, it is preferably laminated so as to be in direct contact with the resin layer 1B constituting the first resin layer.

  The first hard coat layer preferably has a high hardness in order to suppress the occurrence of scratches on the hard coat film surface, and the pencil hardness defined by JIS K5600-5-4 (1999) has a hardness of H or higher. Preferably, 2H or more is more preferable. The upper limit is about 9H.

  The first hard coat layer contains organic particles having an average particle size of 500 nm or less. The average particle size of the organic particles is preferably 400 nm or less, more preferably 300 nm or less, and particularly preferably 250 nm or less. The lower limit average particle size of the organic particles is preferably 50 nm or more, and more preferably 70 nm or more.

  When the first hard coat layer contains organic particles having an average particle diameter of 500 nm or less, the slipping property and the blocking resistance are improved without reducing the transmittance.

  When the average particle diameter of the organic particles contained in the first hard coat layer is larger than 500 nm, the transparency of the hard coat film is lowered. On the other hand, when the average particle diameter of the organic particles is smaller than 50 nm, good slipping property and blocking resistance may not be obtained.

As the resin constituting the organic particles, an acrylic resin, a styrene resin, a polyester resin, a polyurethane resin, a polycarbonate resin, a polyamide resin, a silicone resin, a fluorine resin, or 2 used for the synthesis of the above resin. Examples thereof include copolymer resins of more than one type of monomer. Among these, acrylic resin particles are preferably used. Here, acrylic resin particles are acrylic resin particles, methacrylic resin particles, acrylic monomers or methacrylic monomers and other monomers (for example, styrene, urethane acrylate, urethane methacrylate, polyester acrylate). , Polyester methacrylate, silicone acrylate, silicone methacrylate, etc.).

  Among the copolymer resin particles, styrene-acrylic copolymer resin particles such as styrene-acrylic copolymer resin particles and styrene-methacrylic copolymer resin particles are preferably used.

  These organic particles are preferably synthesized by an emulsion polymerization method, and organic particles having an average particle diameter of 500 nm or less can be obtained by synthesis by an emulsion polymerization method.

  The organic particles can be present in a monodispersed state without agglomerating in the first hard coat layer. In the present invention, the organic particles contained in the first hard coat layer can be present in a monodispersed state without agglomeration. Preferably it is present. Thereby, slipperiness and blocking resistance are further improved without lowering transparency.

  The content of the organic particles in the first hard coat layer is preferably 3% by mass or more with respect to 100% by mass of the total solid content of the first hard coat layer, from the viewpoint of improving slipperiness and blocking resistance. % Or more is more preferable, and 5 mass% or more is particularly preferable. The upper limit of the content of the organic particles is preferably 25% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less with respect to 100% by mass of the total solid content of the first hard coat layer.

  If the content of the organic particles in the first hard coat layer is less than 3% by mass, the slipping property and the blocking resistance may be lowered. On the other hand, when the content of the organic particles in the first hard coat layer exceeds 25% by mass, inconveniences such as a decrease in transparency, a decrease in pencil hardness, or a decrease in wet heat adhesion occur. There is.

  The center line average roughness Ra (Ra1) of the surface of the first hard coat layer is preferably 30 nm or less, more preferably 25 nm or less, and particularly preferably 20 nm or less. The lower limit is preferably 5 nm or more, and more preferably 10 nm or more.

  When the center line average roughness Ra (Ra1) of the surface of the first hard coat layer increases beyond 30 nm, the transmittance may decrease. On the other hand, the center line average roughness Ra ( When Ra1) is less than 5 nm, the slipperiness and blocking resistance may be lowered.

  In order to set the center line average roughness Ra (Ra1) of the surface of the first hard coat layer to 30 nm or less, the content of the organic particles is 25% by mass with respect to 100% by mass of the total solid content of the first hard coat layer. The following is preferable. Moreover, it is preferable that a 1st hard-coat layer does not contain a particle | grain with an average particle diameter of 1 micrometer or more substantially. Here, the fact that the first hard coat layer does not substantially contain particles having an average particle diameter of 1 μm or more means that particles having an average particle diameter of 1 μm or more are not intentionally added to the first hard coat layer.

  The first hard coat layer preferably contains a thermosetting resin or an active energy ray curable resin as a resin, and particularly preferably contains an active energy ray curable resin. Among the active energy ray curable resins, an active energy ray curable acrylic resin is preferable. Here, the active energy ray-curable resin means a resin that is polymerized and cured by active energy rays such as ultraviolet rays and electron beams.

  As a polymerizable compound for obtaining an active energy ray-curable resin, a compound (monomer or oligomer) having a polymerizable functional group such as acryloyl group, methacryloyl group, acryloyloxy group, methacryloyloxy group, vinyl group, and allyl group. Can be mentioned. As described above, an active energy ray-curable acrylic resin is preferable in the present invention, and the polymerizable compound for obtaining the active energy ray-curable acrylic resin is an acryloyl group, a methacryloyl group, an acryloyloxy group, or a methacryloyloxy group. A polymerizable compound (monomer or oligomer) having the following is preferably used.

  The first hard coat layer is formed by applying the active energy ray-curable composition containing the polymerizable compound by a wet coating method, drying it as necessary, and then irradiating the active energy ray to cure. It is preferable that

  Examples of the polymerizable compound (monomer or oligomer) having an acryloyl group, a methacryloyl group, an acryloyloxy group, or a methacryloyloxy group are shown below, but the present invention is not limited to these compounds.

  Examples of the monomer include methyl (meth) acrylate, lauryl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl ( Monofunctional acrylates such as (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxy (meth) acrylate, neopentyl glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol Tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol tri (meth) acrylate Polyfunctional acrylate such as tripentaerythritol hexa (meth) triacrylate, trimethylolpropane (meth) acrylic acid benzoate, trimethylolpropane benzoate, glycerin di (meth) acrylate hexamethylene diisocyanate, pentaerythritol tri (meth) ) Urethane acrylates such as acrylate hexamethylene diisocyanate.

  Examples of the oligomer include polyester (meth) acrylate, polyurethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, alkit (meth) acrylate, melamine (meth) acrylate, and silicone (meth) acrylate. be able to.

  The content of the polymerizable compound in the active energy ray-curable composition is preferably 50% by mass or more and 55% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. More preferably, it is more preferably 60% by mass or more, and particularly preferably 70% by mass or more. The upper limit is preferably 97% by mass or less, and more preferably 95% by mass or less.

  The active energy ray-curable composition preferably contains a photopolymerization initiator in order to initiate polymerization of the polymerizable compound. Specific examples of such photopolymerization initiators include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, 4,4′-dichlorobenzophenone, 4 , 4'-bisdiethylaminobenzophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, methyl benzoyl formate, p-isopropyl-α-hydroxyisobutylphenone, α-hydroxyisobutylphenone, 2,2 -Carbonyl compounds such as dimethoxy-2-phenylacetophenone and 1-hydroxycyclohexyl phenyl ketone, tetramethylthiuram monosulfide, tetramethyl Sulfur compounds such as ruthiuram disulfide, thioxanthone, 2-chlorothioxanthone, and 2-methylthioxanthone can be used. These photopolymerization initiators may be used alone or in combination of two or more.

  The content of the photopolymerization initiator is suitably in the range of 0.1 to 10% by mass and in the range of 0.5 to 8% by mass with respect to 100% by mass of the total solid content of the active energy ray-curable composition. Is preferred.

  The active energy ray curable composition contains organic particles having an average particle diameter of 500 nm or less. The content of the organic particles in the active energy ray curable composition is preferably 3% by mass or more, more preferably 4% by mass or more, more preferably 5% by mass with respect to 100% by mass of the total solid content of the active energy ray curable composition. The above is particularly preferable. The upper limit of the content of the organic particles is preferably 25% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less with respect to 100% by mass of the total solid content of the active energy ray-curable composition.

  The active energy ray-curable composition can further contain various additives such as an antioxidant, an ultraviolet absorber, a leveling agent, an organic antistatic agent, a lubricant, a colorant, and a pigment.

  The refractive index (n1h) of the first hard coat layer is preferably in the range of 1.48 to 1.54, and more preferably in the range of 1.50 to 1.54. The first hard coat layer is formed by applying the above-described active energy ray-curable composition by a wet coating method, drying it as necessary, and then irradiating and curing the active energy ray, thereby providing a refractive index. A first hard coat layer having (n1h) in the range of 1.48 to 1.54 can be obtained.

  The thickness of the first hard coat layer is preferably in the range of 0.5 to 5 μm, more preferably in the range of 0.8 to 4 μm, and particularly preferably in the range of 1 to 3 μm.

  When the thickness of the first hard coat layer is less than 0.5 μm, the hardness of the first hard coat layer is lowered and scratches are easily formed. Moreover, when the thickness of the first hard coat layer is less than 0.5 μm, wet heat adhesion tends to be lowered.

  When the thickness of the first hard coat layer is 5 μm or more, there are cases where inconveniences such as slipperiness and blocking resistance decrease and transmittance decrease.

[Hard coat film]
The hard coat film of the present invention has a first resin layer and a first hard coat layer in this order on at least one surface of the polyester film. The hard coat film of the present invention may have the first resin layer and the first hard coat layer in this order only on one side of the polyester film, or the first resin layer and the first hard coat on both sides of the polyester film, respectively. You may have a layer in this order.

  Further, as another preferred embodiment of the hard coat film of the present invention, the polyester film has a first resin layer and a first hard coat layer in this order on one surface, and the other surface of the polyester film (that is, polyester). Examples thereof include a hard coat film having a second resin layer and a second hard coat layer in this order (on the side opposite to the surface on which the first resin layer and the first hard coat layer are provided).

  When the 2nd resin layer laminated | stacked on the other surface of a polyester film takes the completely same structure as the 1st resin layer laminated | stacked on one surface of a polyester film (namely, 1st resin layer on both surfaces of a polyester film) Even in the case of laminating each of them, it may be referred to as a second resin layer in order to distinguish it from the first resin layer on one side.

  Similarly, when the second hard coat layer laminated on the other surface of the polyester film has the same configuration as the first hard coat layer laminated on the one surface of the polyester film (that is, both surfaces of the polyester film). Even when the first hard coat layer is laminated, the second hard coat layer is sometimes referred to as the first hard coat layer in order to distinguish it from the first hard coat layer on one side.

  Hereinafter, the second resin layer and the second hard coat layer provided on the other surface of the polyester film will be described.

[Second resin layer]
The second resin layer is interposed between the polyester film and the second hard coat layer, and has a function of improving wet heat adhesion between the polyester film and the second hard coat layer. The second resin layer is preferably in direct contact with the polyester film side and the second hard coat layer side, respectively. The second resin layer may be composed of a single resin layer, or may be composed of two or more resin layers. In the present invention, the second resin layer is preferably composed of two or more resin layers.

  The resin constituting the second resin layer preferably includes at least one resin selected from the group consisting of polyester resins, acrylic resins, and urethane resins.

  When the second resin layer is composed of a single resin layer, it is preferable to include at least a polyester resin. As a polyester resin, the thing similar to the polyester resin of the above-mentioned resin layer 1A can be used.

  When the second resin layer is composed of two or more resin layers, the second resin layer includes a resin layer 2A mainly composed of a polyester resin and a resin layer 2B mainly composed of an acrylic resin in order from the polyester film side. It is preferable to include at least.

  When the second resin layer is configured to include at least a resin layer 2A mainly composed of a polyester resin and a resin layer 2B mainly composed of an acrylic resin from the polyester film side, the polyester film and the second hard coat layer, This is preferable because the wet heat adhesion is improved.

  For the resin layer 2A constituting the second resin layer, the same polyester resin as the resin layer 1A constituting the first resin layer can be used. Moreover, the resin layer 2B which comprises a 2nd resin layer can use the acrylic resin similar to the resin layer 1B which comprises a 1st resin layer.

  In the configuration in which the second resin layer includes at least the resin layer 2A and the resin layer 2B, another resin layer (intermediate resin layer) can be included between the resin layer 2A and the resin layer 2B. For example, an intermediate resin layer containing a polyester resin and an acrylic resin may be present between the resin layer 2A and the resin layer 2B.

  The second resin layer preferably contains a crosslinking agent. The second resin layer is preferably a thermosetting resin layer containing a crosslinking agent. When the second resin layer contains a crosslinking agent, wet heat adhesion between the polyester film and the second hard coat layer is improved. The crosslinking agent contained in the second resin layer is the same as the crosslinking agent contained in the first resin layer. Moreover, the method (The resin layer and content which contain a crosslinking agent) to make a 2nd resin layer contain a crosslinking agent is the same as that of a 1st resin layer.

  The second resin layer preferably contains particles. As the particles to be contained in the second resin layer, the same particles as those to be contained in the first resin layer are used. Moreover, the method of making the second resin layer contain particles (the resin layer containing the particles and the content thereof) is the same as that of the first resin layer.

  The second resin in the case where the second resin layer includes at least a resin layer 2A mainly composed of a polyester resin and a resin layer 2B mainly composed of an acrylic resin, which are composed of two or more resin layers in order from the polyester film side. As a method for forming the layer, a method similar to the method for forming the first resin layer described above can be used.

  The total thickness of the second resin layer is preferably 0.01 μm or more, more preferably 0.02 μm or more, and particularly preferably 0.05 μm or more from the viewpoint of improving wet heat adhesion between the polyester film and the second hard coat layer. The upper limit thickness is preferably less than 0.5 μm, more preferably 0.4 μm or less, and particularly preferably 0.3 μm or less. When the total thickness of the second resin layer is 0.5 μm or more, there may be a problem that the wet heat adhesion of the second hard coat layer is lowered or the hardness of the second hard coat layer is lowered.

  In the case where the second resin layer is composed of two or more resin layers and includes at least the resin layer 2A and the resin layer 2B, the thickness of the resin layer 2A increases the wet heat adhesion between the polyester film and the second resin layer. To 0.01 μm or more, preferably 0.02 μm or more, more preferably 0.03 μm or more, and particularly preferably 0.05 μm or more. The upper limit thickness is preferably 0.4 μm or less, more preferably 0.3 m or less, and particularly preferably 0.2 μm or less. When the thickness of the resin layer 2A is larger than 0.4 μm, the wet heat adhesion between the polyester film and the second resin layer may be lowered.

  The thickness of the resin layer 2B is preferably 0.005 μm or more, and more preferably 0.01 μm or more from the viewpoint of improving wet heat adhesion between the second resin layer and the second hard coat layer. The upper limit thickness is preferably 0.2 μm or less, more preferably 0.1 μm or less, and particularly preferably 0.05 μm or less. When the thickness of the resin layer 2B is larger than 0.2 μm, the wet heat adhesion between the second resin layer and the second hard coat layer may be lowered.

  In addition, the ratio of the thickness of the resin layer 2A to the total thickness of the second resin layer is based on 100% of the total thickness of the second resin layer from the viewpoint of improving wet heat adhesion between the polyester film and the second hard coat layer. The range of 50 to 95% is preferable, and the range of 60 to 90% is more preferable. Similarly, the ratio of the thickness of the resin layer 2B to the total thickness of the second resin layer is preferably in the range of 5 to 50%, more preferably in the range of 10 to 40% with respect to 100% of the total thickness of the second resin layer.

  When the second resin layer is composed of two or more resin layers and includes at least the resin layer 2A and the resin layer 2B, the refractive index (n2a) of the resin layer 2A is preferably in the range of 1.55 to 1.61. A range of 56 to 1.60 is more preferable, and a range of 1.57 to 1.59 is particularly preferable. The refractive index (n2b) of the resin layer 2B is preferably in the range of 1.48 to 1.54, more preferably in the range of 1.50 to 1.54, and particularly preferably in the range of 1.51 to 1.54.

  The refractive index (n2h) of the second hard coat layer described later is preferably in the range of 1.48 to 1.54. When such a second hard coat layer is laminated on the second resin layer, the resin layer 2A and By setting the refractive index of the resin layer 2B within the above range, the transmittance can be improved, and the reflection color of the second hard coat layer can be made close to neutral colorless.

  When the second resin layer is composed of two or more resin layers and includes at least the resin layer 2A and the resin layer 2B, the resin layer 2A is preferably in direct contact with the polyester film, and the resin layer 2B is the second hard layer. It is preferable that the coating layer is in direct contact.

[Second hard coat layer]
The second hard coat layer is laminated on the second resin layer. The second hard coat layer is preferably laminated so as to be in direct contact with the second resin layer.

  The second hard coat layer preferably has a high hardness in order to suppress the occurrence of scratches on the hard coat film surface, and the pencil hardness defined by JIS K5600-5-4 (1999) has a hardness of H or higher. Preferably, 2H or more is more preferable. The upper limit is about 9H.

  The second hard coat layer can contain organic particles having an average particle diameter of 500 nm or less. The average particle size of the organic particles is preferably 400 nm or less, more preferably 300 nm or less, and particularly preferably 250 nm or less. The lower limit average particle size of the organic particles is preferably 50 nm or more, and more preferably 70 nm or more.

  The second hard coat layer can contain organic particles having an average particle diameter of 500 nm or less. As the organic particles, the same organic particles as those having an average particle diameter of 500 nm or less contained in the first hard coat layer can be used.

  The effect of improving the slipperiness and blocking resistance of the hard coat film is sufficiently manifested by providing the first hard coat layer containing organic particles having an average particle diameter of 500 nm or less on one surface of the polyester film. The organic particles having an average particle size of 500 nm or less are not necessarily contained in the 2 hard coat layer.

  From the viewpoint of further increasing the transmittance of the hard coat film, it is preferable that the second hard coat layer does not contain organic particles having a flatness of 500 nm or less.

  On the other hand, from the viewpoint of further improving the slipperiness and blocking resistance of the hard coat film, the second hard coat layer preferably contains organic particles having an average particle diameter of 500 nm or less. The content when the second hard coat layer contains organic particles having an average particle size of 500 nm or less is preferably 1% by mass or more, preferably 2% by mass or more with respect to 100% by mass of the total solid content of the second hard coat layer. Is more preferable, and 3% by mass or more is particularly preferable. The upper limit of the content of the organic particles is preferably 15% by mass or less and more preferably 10% by mass or less with respect to 100% by mass of the total solid content of the second hard coat layer.

  When the second hard coat layer contains organic particles having an average particle diameter of 500 nm or less, the second resin layer is composed of two or more resin layers, and a resin layer 2A mainly composed of a polyester resin from the polyester film side. And at least a resin layer 2B mainly composed of an acrylic resin. This improves the wet heat adhesion of the second hard coat layer.

  The center line average roughness Ra (Ra2) of the surface of the second hard coat layer is preferably 25 nm or less, more preferably 20 nm or less, and particularly preferably 15 nm or less. The lower limit is not particularly limited, but is practically about 1 nm.

  In order to set the center line average roughness Ra (Ra2) of the surface of the second hard coat layer to 25 nm or less, the content of the organic particles is 15% by mass with respect to 100% by mass of the total solid content of the second hard coat layer. The following is preferable. Moreover, it is preferable that a 2nd hard-coat layer does not contain a particle | grain with an average particle diameter of 1 micrometer or more substantially. Here, the fact that the second hard coat layer does not substantially contain particles having an average particle diameter of 1 μm or more means that particles having an average particle diameter of 1 μm or more are not intentionally added to the second hard coat layer.

  The center line average roughness Ra (Ra2) of the surface of the second hard coat layer is preferably smaller than the center line average roughness Ra (Ra1) of the surface of the first hard coat layer. The difference (Ra1-Ra2) between the center line average roughness Ra (Ra1) of the surface of the first hard coat layer and the center line average roughness Ra (Ra2) of the surface of the second hard coat layer is specifically 3 nm. The above is preferable, and 5 nm or more is more preferable. The upper limit of the difference (Ra1-Ra2) is preferably 20 nm or less, and more preferably 15 nm or less.

  By making the center line average roughness Ra (Ra2) of the surface of the second hard coat layer smaller than the center line average roughness Ra (Ra1) of the surface of the first hard coat layer, good slipperiness and blocking resistance can be obtained. The transmittance can be further improved while ensuring.

  The second hard coat layer preferably contains a thermosetting resin or an active energy ray curable resin as a resin, and particularly preferably contains an active energy ray curable resin. Among the active energy ray curable resins, an active energy ray curable acrylic resin is preferable. Here, the active energy ray-curable resin means a resin that is polymerized and cured by active energy rays such as ultraviolet rays and electron beams.

  As the polymerizable compound for obtaining the active energy ray-curable acrylic resin, the same compounds as those described in the first hard coat layer can be used.

  As with the first hard coat layer, the second hard coat layer is coated with the active energy ray-curable composition containing the polymerizable compound by a wet coating method, dried as necessary, and then irradiated with active energy rays. Then, it is preferably formed by curing.

  The refractive index (n2h) of the second hard coat layer is preferably in the range of 1.48 to 1.54, and more preferably in the range of 1.50 to 1.54. The first hard coat layer is formed by applying the above-described active energy ray-curable composition by a wet coating method, drying it as necessary, and then irradiating and curing the active energy ray, thereby providing a refractive index. A second hard coat layer having (n2h) in the range of 1.48 to 1.54 can be obtained.

  The thickness of the second hard coat layer is not particularly limited, but is preferably in the range of 0.5 to 10 μm, more preferably in the range of 0.8 to 8 μm, and particularly preferably in the range of 1 to 5 μm.

[Transparent conductive film]
The hard coat film of the present invention is suitable as a base film for a transparent conductive film. That is, the transparent conductive film using the hard coat film of the present invention as a base film is obtained by laminating a transparent conductive layer on at least one surface of the hard coat film of the present invention.

  The transparent conductive layer may be laminated on only one side of the hard coat film of the present invention, or may be laminated on both sides.

  Some examples of the configuration of the transparent conductive film using the hard coat film of the present invention as a base film are exemplified below, but the present invention is not limited thereto.

i) First hard coat layer / first resin layer / polyester film / first resin layer / first hard coat layer / transparent conductive layer
ii) Transparent conductive layer / first hard coat layer / first resin layer / polyester film / first resin layer / first hard coat layer / transparent conductive layer
iii) First hard coat layer / first resin layer / polyester film / second resin layer / second hard coat layer / transparent conductive layer
iv) / Transparent conductive layer / first hard coat layer / first resin layer / polyester film / second resin layer / second hard coat layer
v) Transparent conductive layer / first hard coat layer / first resin layer / polyester film / second resin layer / second hard coat layer / transparent conductive layer.

  Among the above configuration examples, i) or iii) is preferable. In other words, from the viewpoint of ensuring the slipperiness and blocking resistance of the hard coat film in the transparent conductive layer laminating step and processing step, the transparent conductive layer is left unexposed on the first hard coat layer. Is preferred.

  Furthermore, it is preferable that the hard coat layer on the surface on which the transparent conductive layer is laminated is relatively smooth and clear. Therefore, in the configuration example of iii), the center line average roughness Ra (Ra2) of the surface of the second hard coat layer is preferably 25 nm or less, more preferably 20 nm or less, and particularly preferably 15 nm or less.

[Transparent conductive layer]
Examples of the material for forming the transparent conductive layer include tin oxide, indium oxide, antimony oxide, zinc oxide, ITO (indium tin oxide), metal oxide such as ATO (antimony tin oxide), and metal nanowires (for example, silver Nanowire) and carbon naotube. Among these, ITO is preferably used.

The thickness of the transparent conductive layer is preferably 10 nm or more, more preferably 15 nm or more, and particularly preferably 20 nm or more, from the viewpoint of ensuring good conductivity with a surface resistance value of 10 ³ Ω / □ or less. Preferably there is. On the other hand, if the thickness of the transparent conductive layer becomes too large, the color (coloring) may become inconvenient or the transparency may be lowered. Therefore, the upper limit of the thickness of the transparent conductive layer is preferably 60 nm or less. 50 nm or less is more preferable, and 40 nm or less is particularly preferable.

  It does not specifically limit as a formation method of a transparent conductive layer, A conventionally well-known method can be used. Specifically, a dry film forming method (vapor phase film forming method) such as a vacuum vapor deposition method, a sputtering method, an ion plating method, or a wet coating method can be used.

  The transparent conductive layer formed as described above may be patterned. The patterning can form various patterns depending on the application to which the transparent conductive film is applied. In addition, although a pattern part and a non-pattern part are formed by patterning of a transparent conductive layer, as a shape of a pattern part, stripe shape, a lattice shape, etc. are mentioned, for example.

  The patterning of the transparent conductive layer is generally performed by etching. For example, after forming a patterned etching resist film on the transparent conductive layer by a photolithography method, a laser exposure method, or a printing method, the transparent conductive layer is patterned by etching. After the transparent conductive layer is patterned, the etching resist film is peeled off with an alkaline aqueous solution.

  A conventionally well-known thing is used as etching liquid. For example, inorganic acids such as hydrogen chloride, hydrogen bromide, sulfuric acid, nitric acid and phosphoric acid, organic acids such as acetic acid, and mixtures thereof, and aqueous solutions thereof are used.

  Examples of the alkaline aqueous solution used for stripping and removing the etching resist film include 1 to 5% by mass of a sodium hydroxide aqueous solution and a potassium hydroxide aqueous solution.

[Refractive index adjusting layer]
In the configuration example of the transparent conductive film, the transparent conductive layer may be directly laminated on the first hard coat layer or the second hard coat layer, but the transparent conductive layer and the first hard coat layer or the second hard coat layer may be laminated. It is preferable to interpose a refractive index adjusting layer between the coat layer. Hereinafter, the refractive index adjustment layer will be described.

  The refractive index adjusting layer may be composed of only one layer or may be a laminated structure of two or more layers. The refractive index adjustment layer has a function for adjusting the reflection color and transmission color of the transparent conductive layer laminated thereon, or a so-called “bone appearance” in which the patterned portion of the patterned transparent conductive layer is visually recognized. It is a layer having a function to suppress.

  As the configuration of the refractive index adjustment layer, for example, a single layer configuration of a high refractive index layer having a refractive index (n1) of 1.60 to 1.80, and a low refractive index having a refractive index (n2) of 1.30 to 1.50. One layer configuration of the refractive index layer, or a laminated configuration of the high refractive index layer and the low refractive index layer (the low refractive index layer is disposed on the transparent conductive layer side) and the like can be mentioned.

  The refractive index (n1) of the high refractive index layer is further preferably in the range of 1.63 to 1.78, and more preferably in the range of 1.65 to 1.75. The refractive index (n2) of the low refractive index layer is further preferably in the range of 1.30 to 1.48, more preferably in the range of 1.33 to 1.46.

  The thickness of the refractive index adjusting layer (referring to the total thickness in the case of a multilayer structure) is preferably 200 nm or less, more preferably 150 nm or less, particularly preferably 120 nm or less, and most preferably 100 nm or less. The lower limit thickness is preferably 30 nm or more, more preferably 40 nm or more, particularly preferably 50 nm or more, and most preferably 60 nm or more.

  When the transparent conductive layer is patterned, it is preferable that the refractive index adjustment layer has a laminated structure of a high refractive index layer and a low refractive index layer from the viewpoint of suppressing “bone appearance”. In this case, it is preferable that the sum (nm) of the optical thickness of the high refractive index layer and the optical thickness of the low refractive index layer satisfies (1/4) λ (nm). Here, the optical thickness (nm) is the product of the refractive index and the actual layer thickness (nm), and λ is 380 to 780 (nm) which is the wavelength range of the visible light region.

That is, in the present invention, that the total of the optical thickness (nm) of the high refractive index layer and the optical thickness (nm) of the low refractive index layer satisfies (1/4) λ (nm) satisfies the following formula 1. It is to be. In the formula, n1 represents the refractive index of the high refractive index layer, d1 represents the thickness (nm) of the high refractive index layer, n2 represents the refractive index of the low refractive index layer, and d2 represents the thickness (nm) of the low refractive index layer. .
(380 nm / 4) ≦ (n1 × d1) + (n2 × d2) ≦ (780 nm / 4)
95 nm ≦ (n1 × d1) + (n2 × d2) ≦ 195 nm (Formula 1).

  That is, the total of the optical thickness (n1 × d1) of the high refractive index layer and the optical thickness (n2 × d2) of the low refractive index layer is preferably 95 nm or more and 195 nm or less.

  Furthermore, the total of the optical thickness of the high refractive index layer and the optical thickness of the low refractive index layer is more preferably in the range of 95 to 163 nm, particularly preferably in the range of 95 to 150 nm, and most preferably in the range of 100 to 140 nm.

  For the high refractive index layer, for example, an active energy ray-curable composition containing metal oxide fine particles having a refractive index of 1.65 or more is applied by a wet coating method, dried as necessary, and then irradiated with active energy rays. Then, it can be formed by curing. Here, the active energy ray-curable composition is a composition containing the polymerizable compound and the photopolymerization initiator described in the first hard coat layer.

  Examples of the metal oxide fine particles include metal oxide particles such as titanium, zirconium, zinc, tin, antimony, cerium, iron, and indium. Specific examples of the metal oxide fine particles include, for example, titanium oxide, zirconium oxide, zinc oxide, tin oxide, antimony oxide, cerium oxide, iron oxide, zinc antimonate, tin oxide-doped indium oxide (ITO), and antimony-doped tin oxide. (ATO), phosphorus-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, fluorine-doped tin oxide, and the like. These metal oxide fine particles may be used alone or in combination. Among the metal oxide fine particles, titanium oxide and zirconium oxide are particularly preferable because they can increase the refractive index without reducing transparency.

  The content of the metal oxide fine particles in the active energy ray-curable composition is preferably 30% by mass or more, more preferably 40% by mass or more, with respect to 100% by mass of the total solid content of the active energy ray-curable composition. A mass% or more is particularly preferred. The upper limit is preferably 70% by mass or less, and preferably 60% by mass or less.

  The low refractive index layer is, for example, coated with an active energy ray-curable composition containing low refractive index inorganic particles and / or a fluorine-containing compound as a low refractive index material by a wet coating method and, if necessary, dried. It can be formed by irradiating with active energy rays and curing. Here, the active energy ray-curable composition is a composition containing the polymerizable compound and the photopolymerization initiator described in the first hard coat layer.

  As the low refractive index inorganic particles, inorganic particles such as silica and magnesium fluoride are preferable. Further, these inorganic particles are preferably hollow or porous. The content of such low refractive index inorganic particles is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 30% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. Is preferred. The upper limit is preferably 70% by mass or less, preferably 60% by mass or less, and particularly preferably 50% by mass or less.

  Examples of the fluorine-containing compound include fluorine-containing monomers, fluorine-containing oligomers, and fluorine-containing polymer compounds. Here, the fluorine-containing monomer or fluorine-containing oligomer is a monomer or oligomer having in the molecule thereof the above-mentioned polymerizable functional group (functional group containing a carbon-carbon double bond group) and a fluorine atom.

  Examples of the fluorine-containing monomer and fluorine-containing oligomer include 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, and 2- (perfluorobutyl). ) Ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, β- (per Fluoro-containing (meth) acrylic esters such as fluorooctyl) ethyl (meth) acrylate, di- (α-fluoroacrylic acid) -2,2,2-trifluoroethylethylene glycol, di- (α-fluoroacrylic acid) ) -2,2,3,3,3-pentafluoropropylethylene glycol, di (Α-fluoroacrylic acid) -2,2,3,3,4,4,4-heptafluorobutylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,4 5,5,5-nonafluoropentylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,6-undecafluorohexylethylene glycol , Di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptylethylene glycol, di- (α-fluoro Acrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctylethylene glycol, di- (α-fluoroacrylic acid) -3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8-tridecafluorooctylethylene glycol, di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9 , 9-heptadecafluorononylethylene glycol and the like di- (α-fluoroacrylic acid) fluoroalkyl esters.

  Examples of the fluorine-containing polymer compound include a fluorine-containing copolymer having a fluorine-containing monomer and a monomer for imparting a crosslinkable group as constituent units. Specific examples of the fluorine-containing monomer unit include, for example, fluoroolefins (for example, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoro-2,2-dimethyl-1,3-dioxole, etc. ), (Meth) acrylic acid partial or fully fluorinated alkyl ester derivatives (for example, Biscoat 6FM (manufactured by Osaka Organic Chemicals) and M-2020 (manufactured by Daikin)), fully or partially fluorinated vinyl ethers, and the like. As a monomer for imparting a crosslinkable group, in addition to a (meth) acrylate monomer having a crosslinkable functional group in the molecule like glycidyl methacrylate, it has a carboxyl group, a hydroxyl group, an amino group, a sulfonic acid group, etc. ) Acrylate monomers (for example, (meth) acrylic acid, methylol (meth) acrylate, hydroxyalkyl (meth) acrylate, allyl acrylate, etc.).

  The content of the fluorine-containing compound is preferably 30% by mass or more, more preferably 40% by mass or more, and particularly preferably 50% by mass or more with respect to 100% by mass of the total solid content of the active energy ray-curable composition. The upper limit is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 80% by mass or less.

  Of the fluorine-containing compounds, fluorine-containing monomers and fluorine-containing oligomers are preferably used. Since the fluorine-containing monomer and the fluorine-containing oligomer have a polymerizable functional group in the molecule, they contribute to the formation of a dense cross-linked structure of the low refractive index layer and can have a low refractive index.

[Touch panel]
The transparent conductive film having the hard coat film of the present invention as a base fill is preferably used as one of constituent members of the touch panel.

  A resistive touch panel usually has a configuration in which an upper electrode and a lower electrode are arranged via a spacer. However, a transparent conductive film using the hard coat film of the present invention as a base fill has an upper electrode and a lower electrode. Can be used for either or both.

  Capacitive touch panels are usually composed of patterned X and Y electrodes, but the transparent conductive film using the hard coat film of the present invention as a base fill is either an X electrode or a Y electrode. It can be used for either or both.

  The transparent conductive film used for the touch panel is required to have good transparency and workability (sliding property and blocking resistance), but the transparent conductive film using the hard coat film of the present invention as a base fill is The above characteristics can be sufficiently satisfied.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these Examples.

  In addition, the measuring method and evaluation method in a present Example are shown below.

(1) Measurement of thickness of first resin layer and second resin layer A cross section of a polyester film on which the first resin layer and the second resin layer are laminated is cut into ultrathin sections, and RuO ₄ dye, OsO ₄ dye, or both Were observed with a TEM (transmission electron microscope) and photographed by an ultrathin section method using double staining. The total thickness of the first resin layer and the second resin layer was measured from the cross-sectional photograph.

  Moreover, about the thickness of the resin layer 1A and the resin layer 1B which comprise the 1st resin layer, the difference in the resin kind was determined by the density | concentration difference of the dyeing | staining on the said cross-sectional photograph, and each thickness was measured. The thicknesses of the resin layer 2A and the resin layer 2B constituting the second resin layer were also measured in the same manner as described above.

  Moreover, the 1st resin layer applies the mixture of the component which forms the resin layer 1A, and the component which forms the resin layer 1B, and forms the resin layer 1A and the resin layer 1B using the self-phase separation of each component. Also when formed using the method (Production Examples 9 and 10), the total thickness of the first resin layer is measured by the above method. The thicknesses of the resin layer 1A and the resin layer 1B are the total thickness of the first resin layer described above, and the content ratio (mass ratio) of the polyester resin that is the main component of the resin layer 1A and the acrylic resin that is the main component of the resin layer 1B. ).

  Similarly, when the second resin layer was formed using self-phase separation (Production Examples 9 and 10), the thicknesses of the resin layer 2A and the resin layer 2B were measured in the same manner as described above.

  Whether or not the resin layer 1A (resin layer 2A) and the resin layer 1B (resin layer 2B) are formed by phase separation should be observed with a TEM (transmission electron microscope) by the above-described stained ultrathin section method. Can be confirmed.

<Observation method>
-Apparatus: Transmission electron microscope (H-7100FA type, manufactured by Hitachi, Ltd.)
・ Measurement conditions: Acceleration voltage 100kV
Sample preparation: frozen ultrathin section method.

(2) Measurement of the thickness of the first hard coat layer, the second hard coat layer, the high refractive index layer, the low refractive index layer, and the transparent conductive layer The cross section of the hard coat film or the transparent conductive film is cut into ultrathin sections and transmitted. A cross section of the sample was observed at a magnification of 50,000 to 300,000 times at an acceleration voltage of 100 kV with a scanning electron microscope (Hitachi H-7100FA type), and the thickness of each layer was measured. In addition, when the boundary of each layer was not clear, the dyeing | staining process was performed as needed.

(3) Measurement of refractive index Resin layer 1A and resin layer 1B constituting the first resin layer, resin layer 2A and resin layer 2B constituting the second resin layer, first hard coat layer, second hard coat layer, high With respect to a coating film (dry thickness of about 2 μm) formed by coating each coating solution (or composition) of the refractive index layer and the low refractive index layer on a silicon wafer with a spin coater, a temperature condition of 25 ° C. The refractive index at 633 nm was measured with a phase difference measuring device (Nikon Corporation: NPDM-1000).

  The refractive index of the polyester film was measured with an Abbe refractometer according to JIS K7105 (1981), and the average value of the refractive index in the longitudinal direction and the width direction was taken as the refractive index of the polyester film.

(4) Measurement of average particle diameter of organic particles contained in first hard coat layer and second hard coat layer Cross section of first hard coat layer and second hard coat layer is observed with an electron microscope (approximately 20,000 to 50,000 times) The maximum length of each of 30 randomly selected organic particles was measured from the cross-sectional photograph, and the average value of these was taken as the average particle size of the organic particles.

(5) Measurement of average particle diameter of particles contained in first resin layer and second resin layer Using SEM (scanning electron microscope), the surfaces of the first resin layer and the second resin layer laminated on the polyester film Observe the image at a magnification of 10,000 times, connect the image of the particles (light density produced by the particles) to an image analyzer (for example, QTM900 manufactured by Cambridge Instrument), change the observation location, capture the data, and the total number of particles is over 5000 Then, the following numerical processing was performed, and the number average diameter d obtained thereby was defined as the average particle diameter (diameter).
・ D = Σdi / N
Here, di is the equivalent circular diameter of the particle (the diameter of a circle having the same area as the cross-sectional area of the particle), and N is the number.

(6) Total light transmittance of hard coat film Measured using a turbidimeter NDH2000 (manufactured by Nippon Denshoku Industries Co., Ltd.) based on JIS-K7361 (1997).

(7) Measurement of center line average roughness Ra of the surface of the first hard coat layer and the second hard coat layer Based on JIS B0601 (1982), stylus type surface roughness measuring instrument SE-3400 (Kosaka Research Co., Ltd.) ).

<Measurement conditions>
Feeding speed: 0.5mm / S
Evaluation length: 8mm
Cut-off value λc; 0.08 mm.

(8) Wet heat adhesion After leaving the hard coat film in an atmosphere of 60 ° C.-90% RH for 1000 hours, 100 pieces of 1 mm ² crosscuts were put on the surface of the first hard coat layer of the hard coat film, A cellophane tape manufactured by Nichiban Co., Ltd. was affixed on it and pressed strongly with a finger, and then peeled rapidly in the direction of 90 degrees, and the adhesion was evaluated according to the following criteria based on the number remaining. Similarly, the adhesiveness of the surface of the second hard coat layer of the hard coat film was also evaluated.
○: 90/100 (remaining number / measured number) or more x: less than 90/100 (remaining number / measured number).

(9) Sliding property The hard coat film is cut to produce two sheet pieces (20 cm × 15 cm). The two sheet pieces are slightly shifted and overlapped so that the first hard coat layer and the second hard coat layer of the two sheet pieces face each other and placed on a smooth table, and the lower sheet piece is fingered. The quality of the slipperiness was determined by a method of fixing on the table and sliding the upper sheet piece by hand. The measurement environment is 23 ° C. and 55% RH.
○: The slipperiness of the upper sheet piece is good.
X: The upper sheet piece does not slip.

(10) Blocking resistance The hard coat film is cut to produce two sheet pieces (20 cm × 15 cm). These two sheets are superposed so that the first hard coat layer and the second hard coat layer on one side face each other. Next, a sample in which two sheet pieces are overlapped is sandwiched between glass plates, and a weight of about 3 kg is placed thereon and left in an atmosphere of 50 ° C. and 90% (RH) for 48 hours. Next, the overlapping surface was visually observed to confirm the occurrence of Newton rings, and then both were peeled off and evaluated according to the following criteria.
○: Newton ring is not generated before peeling, and light peeling is performed without making a peeling sound at the time of peeling.
X: Newton rings are generated on the entire surface before peeling, and peeling is made with peeling sound during peeling.

(11) Visual evaluation of reflection color of hard coat film A black adhesive tape (Nitto Denko “Vinyl Tape No. 21 Tokuhaba Black”) is pasted on the surface of the second hard coat layer of the hard coat film, and the first hard coat layer The reflection color of this surface was visually observed under a darkroom three-wavelength fluorescent lamp, and the following criteria were used.

Similarly, a black adhesive tape (Nitto Denko “Vinyl Tape No. 21 Tokuhaba Black”) is applied to the surface of the first hard coat layer of the hard coat film, and the reflection color of the second hard coat layer surface is set to three wavelengths in the dark room. It observed visually under the fluorescent lamp and performed on the following references | standards.
○: Reflection color is neutral and almost colorless.
X: The reflected color is slightly colored.

(12) Visibility of transparent conductive layer pattern of transparent conductive film (inhibition of “bone appearance”)
A transparent conductive film was placed on a black plate with the transparent conductive layer on top, and whether or not the pattern portion could be visually confirmed was evaluated according to the following criteria.
○: The pattern portion cannot be visually recognized.
X: A pattern part can be visually recognized.

[Polyester resin used for forming first resin layer and second resin layer]
<Polyester resin 1 (PE1)>
An aqueous dispersion in which a polyester resin having the following copolymer composition is dispersed in water in the form of particles.
・ Polycarboxylic acid component terephthalic acid 34mol%
2,6-Naphthalenedicarboxylic acid 10 mol%
5-Na sulfoisophthalic acid 6 mol%
・ Diol component ethylene glycol 49 mol%
Diethylene glycol 1 mol%.

<Polyester resin 2 (PE2)>
An aqueous dispersion in which a polyester resin having the following copolymer composition is dispersed in water in the form of particles, a polyvalent carboxylic acid component terephthalic acid 38 mol%
Trimellitic acid 12 mol%
・ Diol component ethylene glycol 15 mol%
Neopentyl glycol 18 mol%
1,4-butanediol 17 mol%.

[Acrylic resin used for forming first resin layer and second resin layer]
<Acrylic resin 1 (AC1)>
64% by weight of an aqueous dispersion / copolymerization component methyl methacrylate in which an acrylic resin having the following copolymer composition is dispersed in water in the form of particles
30% by weight ethyl acrylate
Acrylic acid 5% by weight
N-methylolacrylamide 1% by weight.

<Acrylic resin 2 (AC2)>
Aqueous dispersion obtained by dispersing an acrylic resin having the following copolymer composition in water in a particulate form / copolymerization component methyl methacrylate 63 wt%
Ethyl acrylate 35% by weight
Acrylic acid 1% by weight
N-methylolacrylamide 1% by weight.

[Coating liquid used for forming first resin layer and second resin layer]
<Coating liquid a1>
Polyester resin 1 (PE1) / melamine-based crosslinking agent / particles were mixed at a solid content mass ratio of 100/20/3 to prepare coating solution a1.

  As the melamine-based crosslinking agent, a methylol-type melamine-based crosslinking agent (“Nicarac MW12LF” manufactured by Sanwa Chemical Co., Ltd.) and colloidal silica having an average particle diameter of 100 nm (“Snowtex” manufactured by Nissan Chemical Industries, Ltd.) are used. )). In the following coating solutions, the melamine-based crosslinking agent and colloidal silica particles refer to the materials described above.

<Coating liquid a2>
Polyester resin 1 (PE1) / polyester resin 2 (PE2) / melamine-based crosslinking agent / particles were mixed at a solid mass ratio of 10/90/20/3 to prepare coating solution a2.

<Coating liquid b1>
Acrylic resin 1 (AC1) / melamine-based crosslinking agent / colloidal silica particles were mixed at a solid mass ratio of 100/20/3 to prepare coating solution b1.

<Coating liquid b2>
A coating liquid b2 was prepared by mixing acrylic resin 2 (AC2) / melamine-based crosslinking agent / colloidal silica particles at a solid mass ratio of 100/20/3.

<Phase separation coating solution c1>
The coating liquid a1 and the coating liquid b1 were prepared by mixing at a solid content mass ratio of 80:20.

<Phase separation coating solution c2>
The coating liquid a1 and the coating liquid b2 were prepared by mixing at a solid content mass ratio of 80:20.

[Production Example 1]
In the following manner, coating liquid 1 and coating liquid 2 are applied to one side of a polyester film (polyethylene terephthalate (PET) film), the first resin layer is laminated, and coating liquid 1 is similarly applied to the other side. The coating liquid 2 was applied repeatedly to laminate the second resin layer, and the laminated polyester film of Production Example 1 was obtained.

<Manufacture of laminated polyester film>
PET pellets (intrinsic viscosity 0.63 dl / g) substantially free of externally added particles are sufficiently vacuum-dried, then supplied to an extruder, melted at 285 ° C., extruded from a T-shaped die into a sheet shape, It was wound around a mirror-casting drum having a surface temperature of 25 ° C. using an electric application casting method and cooled and solidified. This unstretched film was heated to 90 ° C. and stretched 3.4 times in the longitudinal direction to obtain a uniaxially stretched film. After performing corona discharge treatment in air on both surfaces of the uniaxially stretched film, the coating liquid a1 and the coating liquid b1 were respectively coated on both surfaces of the uniaxially stretched film.

  Next, the uniaxially stretched film coated with the coating liquid a1 and the coating liquid b1 on both sides is gripped with a clip, guided to a preheating zone, dried at an ambient temperature of 75 ° C., raised to 110 ° C. using a radiation heater, and again 90 After drying at ℃, continuously stretched 3.5 times in the width direction in a heating zone at 120 ℃, followed by heat treatment for 20 seconds in a heating zone at 220 ℃ to produce a polyester film with completed crystal orientation did. At this time, the thickness of the polyester film was 100 μm, and the total thickness of the first resin layer and the second resin layer was 0.1 μm, respectively.

  The first resin layer has a resin layer 1A (refractive index 1.59, thickness 0.09 μm) mainly composed of a polyester resin and a resin layer 1B mainly composed of an acrylic resin (refractive index 1.54) in order from the polyester film side. And a thickness of 0.01 μm).

  Similarly to the first resin layer, the second resin layer also has a resin layer 2A (refractive index 1.59, thickness 0.09 μm) mainly composed of a polyester resin and a resin layer mainly composed of an acrylic resin from the polyester film side. 2B (refractive index 1.54, thickness 0.01 μm).

  In addition, the refractive index of the polyester film measured the refractive index of the polyester film manufactured on the conditions similar to the above except not laminating | stacking a 1st resin layer and a 2nd resin layer, and made the value the refractive index of a polyester film. . The refractive index of this polyester film was 1.65. The same applies to the following embodiments.

[Production Example 2]
A laminated polyester film of Production Example 2 was produced in the same manner except that the coating liquid a1 of Production Example 1 was changed to the coating liquid a2. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 3]
A laminated polyester film of Production Example 3 was produced in the same manner except that the coating liquid b1 of Production Example 1 was changed to the coating liquid b2. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 4]
A laminated polyester film of Production Example 4 was produced in the same manner as in Production Example 1 except that the coating liquid a1 was changed to the coating liquid a2 and the coating liquid b1 was changed to the coating liquid b2. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 5]
A laminated polyester film of Production Example 5 was produced in the same manner as in Production Example 1 except that only the coating solution a1 was applied to both surfaces of the uniaxially stretched film so that the dry thickness was 0.1 μm. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 6]
A laminated polyester film of Production Example 6 was produced in the same manner as in Production Example 1 except that only the coating solution a2 was applied to both surfaces of the uniaxially stretched film so that the dry thickness was 0.1 μm. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 7]
A laminated polyester film of Production Example 7 was produced in the same manner as in Production Example 1 except that only the coating solution b1 was applied to both surfaces of the uniaxially stretched film so that the dry thickness was 0.1 μm. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 8]
A laminated polyester film of Production Example 8 was produced in the same manner as in Production Example 1 except that only the coating liquid b2 was applied to both surfaces of the uniaxially stretched film so that the dry thickness was 0.1 μm. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

[Production Example 9]
A laminated polyester film of Production Example 9 was produced in the same manner as in Production Example 1, except that the phase separation coating solution c1 was applied to both surfaces of the uniaxially stretched film. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

  This laminated polyester film has, on one surface, in order from the polyester film side, a resin layer 1A (refractive index 1.59) containing a polyester resin as a main component and a resin layer 1B (refractive index 1. 54), the first resin layer (total thickness 0.1 μm) was confirmed to be formed. Similarly, on the other side, in order from the polyester film side, a resin layer 2A (refractive index 1.59) mainly composed of a polyester resin and a resin layer 2B (refractive index 1.54) mainly composed of an acrylic resin. It was confirmed that the configured second resin layer (total thickness 0.1 μm) was formed.

  The phase separation coating liquid c1 contains 80% by mass of the polyester resin, which is the main component of the resin layer 1A, and 20% by mass of the acrylic resin, which is the main component of the resin layer 1B, and the total thickness of the first resin layer is Since the thickness is 0.1 μm, the thickness of the resin layer 1A is 0.08 μm (0.1 μm × 0.8), and the thickness of the resin layer 1B is 0.02 μm (0.1 μm × 0.2). Similarly, the thickness of the resin layer 2A was 0.08 μm, and the thickness of the resin layer 2B was 0.02 μm.

[Production Example 10]
A laminated polyester film of Production Example 10 was produced in the same manner as in Production Example 1 except that the phase separation coating solution c2 was applied to both surfaces of the uniaxially stretched film. Table 1 shows the refractive indexes and thicknesses of the first resin layer and the second resin layer of the laminated polyester film.

  This laminated polyester film has, on one surface, in order from the polyester film side, a resin layer 1A (refractive index 1.59) containing a polyester resin as a main component and a resin layer 1B (refractive index 1. 52), the first resin layer (total thickness 0.1 μm) was confirmed to be formed. Similarly, on the other surface, in order from the polyester film side, a resin layer 2A (refractive index 1.59) mainly composed of a polyester resin and a resin layer 2B (refractive index 1.52) mainly composed of an acrylic resin. It was confirmed that the configured second resin layer (total thickness 0.1 μm) was formed.

  The phase separation coating liquid c2 contains 80% by mass of the polyester resin, which is the main component of the resin layer 1A, and 20% by mass of the acrylic resin, which is the main component of the resin layer 1B, and the total thickness of the first resin layer is Since the thickness is 0.1 μm, the thickness of the resin layer 1A is 0.08 μm (0.1 μm × 0.8), and the thickness of the resin layer 1B is 0.02 μm (0.1 μm × 0.2). Similarly, the thickness of the resin layer 2A was 0.08 μm, and the thickness of the resin layer 2B was 0.02 μm.

[Example 1]
A hard coat film was prepared in the following manner.

The surface of the laminated polyester film of Production Example 1 on which the first resin layer was laminated was coated with the following active energy ray-curable composition a with a gravure coater, dried at 80 ° C., and then irradiated with ultraviolet rays (integrated light amount 400 mJ / cm ² ) was applied to form a first hard coat layer having a thickness of 1.5 μm. The refractive index of the first hard coat layer was 1.52.

Next, in the same manner as described above, the active energy ray-curable composition a was applied to the surface of the laminated polyester film on which the second resin layer was laminated, and dried at 80 ° C. A second hard coat layer having a thickness of 1.5 μm was formed by irradiation with a light amount of 400 mJ / cm ² . The refractive index of this second hard coat layer was 1.52.

<Active energy ray-curable composition a>
92 parts by mass of dipentaerythritol hexaacrylate as a polymerizable compound, and solid styrene-acrylic copolymer resin particles (trade name “STAPHYLOID EA-1135” manufactured by Ganz Kasei Co., Ltd .; average particle diameter of 130 nm) as organic particles are solid. 8 parts by mass, 5 parts by mass of a photopolymerization initiator (“Irgacure (registered trademark) 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) in an organic solvent (ethyl acetate: toluene = 1: 1 (mass ratio)) It is a composition (solid content concentration 30% by mass) dissolved or dispersed in (mixed solvent).

[Examples 2-6, Comparative Examples 1-4]
In Example 1, hard coat films of Examples 2 to 6 and Comparative Examples 1 to 4 were produced in the same manner except that the laminated polyester film of Production Example 1 was changed to the laminated polyester film of Production Example 2 to Production Example 10. did. Details are shown in Table 2.

[Example 7]
A hard coat film was produced in the same manner as in Example 1 except that the active energy ray-curable composition for forming the second hard coat layer was changed to the following active energy ray-curable composition b. The refractive index of the second hard coat layer was 1.52.

<Active energy ray-curable composition b>
50 parts by mass of dipentaerythritol hexaacrylate as a polymerizable compound and 50 parts by mass of urethane acrylate oligomer (“Art Resin UN901T” manufactured by Negami Kogyo Co., Ltd.), a photopolymerization initiator (manufactured by Ciba Specialty Chemicals “ Irgacure (registered trademark) 184 ") is a composition (solid content concentration 30% by mass) in which 5 parts by mass is dissolved in an organic solvent (a mixed solvent of methyl ethyl ketone: cyclohexanone = 1: 1 (mass ratio)).

[Example 8]
In Example 1, the laminated polyester film is changed to the laminated polyester film of Production Example 9, and the active energy ray curable composition for forming the second hard coat layer is changed to the active energy ray curable composition b. A hard coat film was prepared in the same manner except that.

[Example 9]
In Example 1, the laminated polyester film is changed to the laminated polyester film of Production Example 10, and the active energy ray-curable composition for forming the second hard coat layer is changed to the active energy ray-curable composition b. A hard coat film was prepared in the same manner except that.

[Comparative Example 5]
In Example 1, the active energy ray-curable composition for forming the first hard coat layer is changed to the following active energy ray-curable composition c, and the active energy ray for forming the second hard coat layer. A hard coat film was produced in the same manner except that the curable composition was changed to the active energy ray-curable composition b. The refractive index of the first hard coat layer was 1.52.

<Active energy ray-curable composition c>
92 parts by mass of dipentaerythritol hexaacrylate as a polymerizable compound, 5 parts by mass of organic particles “KMP590” (average particle diameter 1500 nm) manufactured by Shin-Etsu Chemical Co., Ltd. as organic particles in terms of solid content, a photopolymerization initiator (Ciba A composition (solid content) obtained by dissolving or dispersing 5 parts by mass of “Irgacure (registered trademark) 184” manufactured by Specialty Chemicals Co., Ltd. in an organic solvent (a mixed solvent of ethyl acetate: toluene = 1: 1 (mass ratio)) The concentration is 30% by mass).

[Comparative Example 6]
In Example 1, a hard coat film was prepared in the same manner except that the active energy ray-curable composition for forming the first hard coat layer and the second hard coat layer was changed to the active energy ray-curable composition b. Produced.

[Comparative Example 7]
In Example 1, the active energy ray-curable composition for forming the first hard coat layer is changed to the following active energy ray-curable composition d, and the active energy for forming the second hard coat layer A hard coat film was produced in the same manner except that the linear curable composition was changed to the following active energy ray curable composition b. The refractive index of the first hard coat layer was 1.51.

<Active energy ray-curable composition d>
92 parts by mass of dipentaerythritol hexaacrylate as a polymerizable compound and 30 parts by mass of colloidal silica (“Snowtex” manufactured by Nissan Chemical Industries, Ltd .; average particle diameter 100 nm) as inorganic particles in terms of solid content, photopolymerization Composition in which 5 parts by mass of an initiator (“Irgacure (registered trademark) 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) is dissolved or dispersed in an organic solvent (a mixed solvent of ethyl acetate: toluene = 1: 1 (mass ratio)). Product (solid content concentration 30 mass%).

[Evaluation of hard coat film]
About the hard coat film produced by said Example and comparative example, total light transmittance, wet heat adhesiveness, slipperiness, blocking resistance, reflected color, and centerline average roughness Ra were evaluated. The results are shown in Table 2.

  From the results in Table 2, it can be seen that the hard coat films of the examples of the present invention have high total light transmittance and good wet heat adhesion, slipperiness, and blocking resistance. In the hard coat films of Examples 1, 3, and 5-9, the refractive index (n1a) of the resin layer 1A and the refractive index (n2a) of the resin layer 2A are in the range of 1.55 to 1.61, respectively. The refractive index (n1b) of the resin layer 1B and the refractive index (n2b) of the resin layer 2B were in the range of 1.48 to 1.54, and the reflected color was good.

  On the other hand, in the hard coat films of Comparative Example 1 and Comparative Example 2, the first resin layer is composed only of the resin layer 1A mainly composed of the polyester resin, and the second resin layer is the resin layer 2A mainly composed of the polyester resin. Since it is comprised only, wet heat adhesiveness is inferior.

  In the hard coat films of Comparative Example 3 and Comparative Example 4, the first resin layer is composed only of the resin layer 1B mainly composed of acrylic resin, and the second resin layer is composed only of the resin layer 2B mainly composed of acrylic resin. Since it is comprised, wet heat adhesiveness is inferior.

  In the hard coat film of Comparative Example 5, the first hard coat layer contained organic particles having an average particle diameter larger than 500 nm, and thus the total light transmittance was lowered.

  The hard coat film of Comparative Example 6 was poor in slipperiness and blocking resistance because the first hard coat layer did not contain organic particles having an average particle diameter of 500 nm or less.

  In the hard coat film of Comparative Example 7, the first hard coat layer contained inorganic particles having an average particle diameter of 100 nm, and the total light transmittance was lowered.

[Example 10]
A transparent conductive film was produced in the following manner.

  On the second hard coat layer of the hard coat film of Example 1, the following high refractive index layer and low refractive index layer are laminated in this order as a refractive index adjusting layer, and the following transparent conductive material is further formed on the low refractive index layer. The layers were laminated to produce a transparent conductive film.

<Lamination of high refractive index layer>
The following active energy ray-curable composition for forming a high refractive index layer was applied by a gravure coating method, dried at 90 ° C., and then cured by irradiation with ultraviolet rays of 400 mJ / cm ² to form a high refractive index layer. The high refractive index layer had a refractive index (n1) of 1.68 and a thickness (d1) of 50 nm.

(Active energy ray-curable composition for forming a high refractive index layer)
21 parts by mass of dipentaerythritol hexaacrylate, 21 parts by mass of urethane acrylate oligomer (“UN-901T” from Negami Kogyo Co., Ltd .; containing 9 polymerizable functional groups in the molecule), 55 parts by mass of zirconium oxide, and photopolymerization It was prepared by dispersing or dissolving 3 parts by weight of an initiator (“Irgacure (registered trademark) 184” manufactured by Ciba Specialty Chemicals) in an organic solvent.

<Lamination of low refractive index layer>
The following active energy ray-curable composition for forming a low refractive index layer was applied by a gravure coating method, dried at 90 ° C., and then cured by irradiation with ultraviolet rays of 400 mJ / cm ² to form a low refractive index layer. The low refractive index layer had a refractive index (n2) of 1.40 and a thickness (d2) of 40 nm.

(Active energy ray-curable composition for forming a low refractive index layer)
Di- (α-fluoroacrylic acid) -2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluorononylethylene glycol 87 parts by mass, 10 parts by mass of dipentaerythritol hexaacrylate, and 3 parts by mass of a photopolymerization initiator (“Irgacure (registered trademark) 184” manufactured by Ciba Specialty Chemicals Co., Ltd.) were prepared by dispersing or dissolving in an organic solvent. .

<Lamination of transparent conductive layer>
The ITO film was laminated by a sputtering method so as to have a thickness of 30 nm, and the ITO film was patterned (etching process) to form a transparent conductive layer patterned into a lattice pattern.

  For patterning of the ITO film, a patterned etching resist film is formed on the ITO film by photolithography, and then etched using a 5 mass% aqueous hydrogen chloride solution, and then the etching resist film is treated with 2 mass% of water. It was performed by peeling off using an aqueous sodium oxide solution.

[Examples 11 to 13]
In Example 10, the transparent conductive film of Examples 11-13 was produced similarly except having changed the hard coat film into the hard coat film of Examples 7-9. Here, Example 11 used the hard coat film of Example 7, Example 12 used the hard coat film of Example 8, and Example 13 used the hard coat film of Example 9.

[Evaluation of Transparent Conductive Films of Examples 10 to 13]
The hard coat films of Examples 1 and 7 to 9 used for the transparent conductive films of Examples 10 to 13 have high total light transmittance, good wet heat adhesion, slipperiness, blocking resistance, and reflection color. Yes, suitable for transparent conductive film.

  Moreover, all the transparent conductive films of Examples 10 to 13 satisfy the above-described formula (1) as a refractive index adjusting layer between the second hard coat layer of the hard coat film and the transparent conductive layer (ITO film). Since the high refractive index layer and the low refractive index layer were interposed, the “bone appearance” inhibitory property was “◯”.

That is, the optical thickness of the high refractive index layer (n1 × d1 = 1.68 × 50 nm) is 84 nm, and the optical thickness of the low refractive index layer (n2 × d2 = 1.40 × 40 nm) is 56 nm. And the low refractive index layer has a total optical thickness of 140 nm, which satisfies the above-described formula (1) shown below.
(380 nm / 4) ≦ (n1 × d1) + (n2 × d2) ≦ (780 nm / 4)
95 nm ≦ (n1 × d1) + (n2 × d2) ≦ 195 nm (Formula 1).

Claims (10)

  At least one surface of the polyester film has a first resin layer composed of two or more resin layers and a first hard coat layer in this order, and the first resin layer has a polyester resin in order from the polyester film side. A hard coat film comprising at least a resin layer 1A having a main component and a resin layer 1B having an acrylic resin as a main component, wherein the first hard coat layer contains organic particles having an average particle diameter of 500 nm or less. .   The refractive index (nf) of the polyester film is 1.62-1.70, the refractive index (n1a) of the resin layer 1A is 1.55-1.61, and the refractive index (n1b) of the resin layer 1B is 1. The hard coat film according to claim 1, wherein the first hard coat layer has a refractive index (n1h) of 1.48 to 1.54.   The hard coat film according to claim 1, wherein the organic particles are acrylic resin particles.   The hard coat film according to any one of claims 1 to 3, wherein a center line average roughness Ra (Ra1) of a surface of the first hard coat layer is 5 to 30 nm.   The polyester film has a second resin layer composed of two or more resin layers and a second hard coat layer in this order on the surface opposite to the surface on which the first resin layer and the first hard coat layer are provided. The second resin layer includes at least a resin layer 2A mainly composed of a polyester resin and a resin layer 2B mainly composed of an acrylic resin in order from the polyester film side. Hard coat film.   The refractive index (nf) of the polyester film is 1.62-1.70, the refractive index (n2a) of the resin layer 2A of the second resin layer is 1.55-1.61, and the refractive index of the resin layer 2B ( The hard coat film according to claim 5, wherein n2b) is from 1.48 to 1.54, and a refractive index (n2h) of the second hard coat layer is from 1.48 to 1.54.   The center line average roughness Ra (Ra2) of the surface of the second hard coat layer is 25 nm or less, and the center line average roughness Ra (Ra1) of the surface of the first hard coat layer and the second hard coat layer The hard coat film according to claim 5 or 6, wherein a difference (Ra1-Ra2) from the surface centerline average roughness Ra (Ra2) is 3 nm or more.   The transparent conductive film which has a transparent conductive layer in the at least one surface of the hard coat film in any one of Claims 1-7. A high refractive index layer having a refractive index (n1) in the range of 1.60 to 1.80 and a refractive index (n2) of 1.30 as a refractive index adjusting layer between the hard coat film and the transparent conductive layer. And the total thickness of the optical thickness (nm) of the high refractive index layer and the low refractive index layer is (1/4) λ (nm The transparent conductive film according to claim 8, wherein
However, (lambda) is 380-780 (nm).   A touch panel comprising the transparent conductive film according to claim 8 or 9 as a constituent member of the touch panel.