JP6048419B2 - Method for producing hard coat film and method for producing polarizing plate - Google Patents

Description

The present invention relates to a manufacturing method and a manufacturing method of the polarizing plate of the hard coat film. More particularly, it relates to a flatness method for producing a hard coat film which suppresses the occurrence of deterioration or unevenness, and excellent polarizing plate production method of visibility using the hard coat film when wound into a roll.

  In recent years, liquid crystal display devices have attracted attention as image display elements. Liquid crystal display devices are widely used in monitors for personal computers and portable devices, and for television applications because of their various advantages, such as low voltage and low power consumption, enabling miniaturization and thinning. In order to prevent physical damage, a film having a hard coat layer on a cellulose ester film such as a triacetate film (hereinafter referred to as a hard coat film) is used on the surface of the liquid crystal display device.

  In general, a panel of a liquid crystal display device has a structure in which a liquid crystal cell is sandwiched between two polarizing plates. The polarizing plate used on the front side is a polyvinyl alcohol (hereinafter abbreviated as PVA) film in which iodine or a dichroic dye is adsorbed and dyed between a hard coat film and a cellulose ester film in a certain direction. It has a three-layer structure with a polarizing element (polarizing film) stretched and oriented in between. When laminating a hard coat film or a cellulose ester film on the polarizing film, these films are laminated after alkali treatment in order to improve the adhesion between the PVA and the hard coat film and between the PVA and the cellulose ester film.

  Recently, with the advent of smartphones and the like, further downsizing and thinning of liquid crystal display devices are required, and thinning of members such as polarizing plates used in liquid crystal display devices is also desired. Therefore, thinning of hard coat films and cellulose ester films used for polarizing plates has been strongly demanded.

  Moreover, the thin hard coat film needs to have a certain degree of slipperiness in order to prevent generation of scratches and wrinkles during roll conveyance during production. Therefore, it is considered desirable to make the surface contact angle with water relatively high.

  On the other hand, the polarizing plate is produced by a roll-to-roll method from the viewpoint of production, and is produced in a roll state. In addition, by making the protective film of the polarizing plate into a thin film, the polarizing plate itself can be wound up and transported in a roll state, or rolled out from the roll-shaped polarizing plate when being attached to a liquid crystal panel.・ Manufacturing of liquid crystal display devices using the two-panel method is also under consideration.

  However, when the polarizing plate is wound in a roll state, the stress due to the weight of the winding is large due to the three-layer structure, and the polarizing plates overlapped in a roll shape are more easily stuck together. I can not cope. In order to suppress sticking between polarizing plates, it is necessary to provide an air layer between the polarizing plate wound in a roll shape and the polarizing plate. When used, the air layer is compressed by the dead weight of the winding, and it becomes clear that the problem of winding deviation when the compressed air layer escapes to the outside of the winding becomes large, leading to a decrease in productivity. It was.

  In particular, in the polarizing plate in which the hard coat film or the cellulose ester film is formed of a thin film, the compressed air layer is easily pulled out of the winding, and the problem of winding deviation is likely to occur.

  Moreover, the polarizing plate comprised with the thin film was easy to buckle-deform with the stress when wound by roll shape, and the nonuniformity by deterioration of a planarity or distortion was easy to generate | occur | produce. In particular, unevenness due to deterioration of flatness and distortion was remarkable after a durability test assuming long-term transportation.

  When the polarizing plate is in the roll state, the hard coat layer of the hard coat film and the film of the cellulose ester film are wound in a state where the films face each other. It is disclosed.

  The technique disclosed in Patent Document 1 includes one or two or more strip-shaped end hard coat layers at both ends in the width direction of the hard coat layer, and the film thickness of the end hard coat layer is set to the thickness of the hard coat layer. This is a technique for preventing winding slippage by causing blocking at the end by reducing the slipperiness of the film by making it thicker than the thickness.

  Although the above-described technique can achieve a certain degree of effect in preventing winding deviation in a single film, the effect is insufficient in preventing winding deviation particularly in a polarizing plate in which the hard coat film or cellulose ester film is thinned. It was. Moreover, it is difficult to control only the edge film thickness, and there is a problem in productivity.

JP2011-218618A

The present invention has been made in view of the above-described problems and situations, and its solution is to suppress slippage between films and to prevent winding misalignment when wound into a roll shape, or to be wound into a roll shape. It is to provide a method for producing a hard coat film in which buckling deformation and distortion are suppressed, and flatness and unevenness are suppressed. Moreover, it is providing the manufacturing method of the polarizing plate excellent in visibility using this hard coat film.

In order to solve the above problems, the present inventor is a method for producing a hard coat film having a hard coat layer on a substrate film that has been thinned in the process of studying the cause of the above problem, etc. By adjusting the difference (θ _Δ ) in water contact angle before and after alkali treatment within a specific range and having an air layer of a specific thickness between roll-shaped layers, the hard coat film and the hard coat film When a polarizing plate using a roll is wound into a roll, the slipping property between the films is suppressed, so even if the air layer between the roll layers is compressed by its own weight, the air layer does not escape to the outside. Therefore, the inventors have found that a method for producing a hard coat film free from winding deviation and a method for producing a polarizing plate can be obtained, and the present invention has been achieved. Moreover, since an air layer was hold | maintained between roll-shaped interlayers, the stress load to a film was suppressed, and it discovered that a buckling deformation and distortion were hard to produce also in a thin film film, and planarity and nonuniformity could be suppressed. That is, the surface state of the hard coat layer of the hard coat film is changed before and after the alkali saponification treatment performed when a hard coat film serving as a protective film is attached to the polarizer in the production of the polarizing plate. It has been found that, by having an air layer having a specific thickness between the roll-shaped layers, both the problems at the time of manufacturing the hard coat film and the problems at the time of manufacturing the roll-shaped polarizing plate can be solved.

  In addition, the hard coat film of the present invention maintains an air layer between roll-shaped layers in addition to winding misalignment, and therefore has excellent blocking properties (sticking between films), and is excellent in flatness and unevenness. Provided excellent visibility when used in a glass scattering prevention film for a display device, a touch panel and a liquid crystal display device.

  That is, the said subject which concerns on this invention is solved by the following means.

1. A method for producing a hard coat film, comprising producing a hard coat film having a hard coat layer on at least one surface of a cellulose ester film having a thickness in the range of 5 to 34 μm, and winding the roll into a roll. When the layer is alkali-treated under the conditions shown below, the water contact angle (θ) before the alkali treatment is in the range of 50 to 120 °, and the difference between the water contact angles before and after the alkali treatment (θ _Δ ) is adjusted to be within a range of 5 to 55 ° ,
The manufacturing method of the hard coat film characterized by making the thickness of the air layer hold | maintained between layers when winding in roll shape in the range of 0.5-10 micrometers .

Here, the difference (θ _Δ ) between the water contact angle before and after the alkali treatment was alkali-treated under the conditions shown below from the water contact angle (θ) of the hard coat layer before the alkali treatment of the hard coat film. This is a value obtained by subtracting the water contact angle (θa) of the subsequent hard coat layer to obtain the difference (θΔ) in water contact angle before and after the alkali treatment.
The alkali treatment condition is a condition in which the hard coat film is immersed in a 2.5 mol / L potassium hydroxide solution at a temperature of 50 ° C. for 120 seconds.
The contact angle with water is that the sample is left for 24 hours in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%, and then 1 μL of pure water is dropped using a contact angle meter in an atmosphere of a temperature of 23 ° C. and a relative humidity of 55%. The contact angle of pure water after 1 minute is measured. In addition, it is the value which measured 7 times and averaged five measured values except the maximum value and minimum value of the measured value.
2. 2. The method for producing a hard coat film according to claim 1, wherein the arithmetic average roughness Ra (JIS B0601: 2001) of the hard coat layer is adjusted to be in the range of 2 to 100 nm .

3. The method for producing a hard coat film according to item 1 or 2 , wherein the hard coat layer contains an active energy ray-curable isocyanurate derivative.

4). When the retardation value of the cellulose ester film was measured at an optical wavelength of 590 nm under an environment of a temperature of 23 ° C. and a relative humidity of 55%, the in-plane retardation value Ro was in the range of 0 to 10 nm, and the thickness direction The method for producing a hard coat film according to any one of items 1 to 3, wherein the retardation value Rth is adjusted so as to fall within a range of −10 to 10 nm.

5. Polarization using a hard coat film produced by the method for producing a hard coat film according to any one of items 1 to 4 and a cellulose ester film having a thickness in the range of 5 to 34 μm. Sandwich the element , and
The thickness of the air layer held between the layers when winding in a roll shape is within the range of 0.5 to 10 μm.
Method for producing a polarizing plate, characterized in that a.

By the above means of the present invention, it is possible to provide a method for producing a hard coat film that suppresses slipperiness between films and has a high anti-winding effect when wound into a roll in a thin film. Moreover, since the hard coat film is excellent in flatness and unevenness, a method for producing a polarizing plate having excellent visibility can be provided by using the hard coat film.

  The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

  The hard coat layer of the hard coat film is wound into a roll shape by bringing the wettability (contact angle with water) of the hard coat film close to the wettability of the cellulose ester film used as a substrate and making them hydrophilic to each other. It is presumed that slipping when the films come into contact with each other is suppressed, and an effect of preventing winding deviation is obtained. In addition, the air layer between the roll layers is also retained, and the stress load on the film is suppressed, so buckling deformation and distortion are unlikely to occur, and it is estimated that a hard coat film excellent in flatness and unevenness can be obtained. Yes.

An example of a touch panel display device using the hard coat film according to the present invention. An example of an image display device with a touch panel An example of a schematic sectional view using a glass scattering prevention film for an image display device in the image display device Cross section of polarizing plate 101

The method for producing a hard coat film of the present invention is a hard coat film in which a hard coat film having a hard coat layer is prepared on at least one surface of a cellulose ester film having a thickness in the range of 5 to 34 μm and wound into a roll shape. A method for producing a film , wherein when the hard coat layer is alkali-treated under the following conditions, the water contact angle (θ) before the alkali treatment is in the range of 50 to 120 °, and the alkali The water contact angle difference (θ _Δ ) before and after the treatment is adjusted to be within the range of 5 to 55 °, and the thickness of the air layer held between the layers when winding in the roll shape is set to 0. It is characterized by being in the range of 5 to 10 μm .

Here, the difference (θ _Δ ) between the water contact angle before and after the alkali treatment was alkali-treated under the conditions shown below from the water contact angle (θ) of the hard coat layer before the alkali treatment of the hard coat film. This is a value obtained by subtracting the water contact angle (θa) of the subsequent hard coat layer to obtain the difference (θΔ) in water contact angle before and after the alkali treatment.
The alkali treatment condition is a condition in which the hard coat film is immersed in a 2.5 mol / L potassium hydroxide solution at a temperature of 50 ° C. for 120 seconds.
The contact angle with water is that the sample is left for 24 hours in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%, and then 1 μL of pure water is dropped using a contact angle meter in an atmosphere of a temperature of 23 ° C. and a relative humidity of 55%. The contact angle of pure water after 1 minute is measured. In addition, it is the value which measured 7 times and averaged five measured values except the maximum value and minimum value of the measured value.
This feature is technical feature common to the invention according to each請 Motomeko.

In addition, as an embodiment of the present invention, the arithmetic average roughness Ra (JIS B0601: 2001) of the hard coat layer is adjusted so as to be in the range of 2 to 100 nm from the viewpoint of manifesting the effects of the present invention. It is preferable because the slipperiness between the films is suppressed and the effect of preventing the winding deviation is enhanced.

  Moreover, it is preferable that the hard coat layer contains an active energy ray-curable isocyanurate derivative because the effect of suppressing the slipperiness between films is enhanced.

Furthermore, in the present invention, when the cellulose ester film has a retardation value measured at a light wavelength of 590 nm in an environment of a temperature of 23 ° C. and a relative humidity of 55% RH, the in-plane retardation value Ro is in the range of 0 to 10 nm. The retardation value Rth in the thickness direction is preferably adjusted to be within a range of −10 to 10 nm. Thereby, there exists an effect that a hard coat film with favorable visibility is obtained.

Further, the air that is held between the layers when the polarizing element is sandwiched between the hard coat film according to the present invention and the cellulose ester film having a film thickness in the range of 5 to 34 μm and wound into a roll shape. It is preferable that the manufacturing method of the polarizing plate has a layer thickness in the range of 0.5 to 10 μm, even if it is a thin-film polarizing plate, winding deviation can be prevented.

  Since the hard coat film of the present invention has good visibility, it can be suitably provided for a glass scattering prevention film for an image display device, a touch panel and a liquid crystal display device.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

<Difference in contact angle with water before and after alkali treatment (θ _Δ )>
First, the difference (θ _Δ ) in water contact angle before and after the alkali treatment according to the present invention will be described.

In the hard coat film of the present invention, the difference (θ _Δ ) in water contact angle before and after the alkali treatment of the hard coat layer is in the range of 5 to 55 °. More preferably, the difference (θ _Δ ) in water contact angle is in the range of 15 to 50 °.

Here, the difference (θ _Δ ) between the water contact angle before and after the alkali treatment was alkali-treated under the conditions shown below from the water contact angle (θ) of the hard coat layer before the alkali treatment of the hard coat film. This is a value obtained by subtracting the water contact angle (θa) of the subsequent hard coat layer to obtain the difference (θΔ) in water contact angle before and after the alkali treatment.

  The conditions for the alkali treatment are conditions for immersing the hard coat film in a 2.5 mol / L potassium hydroxide solution at a temperature of 50 ° C. for 120 seconds.

  In addition, the contact angle with water is measured by a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.) in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55% after leaving the sample for 24 hours in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%. The contact angle of pure water is measured 1 minute after dropping 1 μL of pure water using a trade name DropMaster DM100). It is a value obtained by measuring seven times and averaging five measured values excluding the maximum value and the minimum value.

In the present invention, when the difference (θ _Δ ) in water contact angle before and after alkali treatment of the hard coat layer satisfies the above range, the hard coat layer exhibits hydrophilicity, and when the hard coat layer is wound into a roll, Slip property between films is suppressed, and an effect of preventing winding deviation is obtained.

Water contact angle of the hard coat layer before the alkali treatment (theta) is in the range of 50 to 120 °, good Mashiku is in the range of 60 to 110 °. Further, the water contact angle (θa) of the hard coat layer after the alkali treatment is not particularly limited as long as the difference from the hard coat layer before the alkali treatment is within a range of 5 to 55 °, and the roll shape It can select suitably in the range which suppresses the winding shift | offset | difference in a polarizing plate, Specifically, the inside of the range of 40-110 degrees is preferable, Most preferably, it exists in the range of 40-80 degrees.

Further, in the present invention, it is preferable in the present invention that the contact angle with water decreases after the alkali treatment, and the difference (θ _Δ ) in the contact angle with water satisfies the above range.

  The alkali treatment of the present invention includes a step of immersing at least a hard coat film in an alkali solution (hereinafter also referred to as a saponification step), followed by washing with water and drying, and the conditions for the alkali treatment are the conditions described above.

  Further, after the alkali treatment, neutralization in an acidic water step may be performed, followed by washing with water and drying.

By adjusting the types and amounts of additives such as surfactants and fluorine-based compounds described later, and the curing conditions (such as oxygen concentration adjustment) of the hard coat layer forming method, the difference in contact angle with water before and after alkali treatment (θ _Δ ) can be adjusted to satisfy the above range.

<Hard coat film>
(Hard coat layer)
The hard coat layer according to the present invention preferably contains an actinic radiation curable resin from the viewpoint of excellent mechanical film strength (abrasion resistance, pencil hardness). That is, it is a layer mainly composed of a resin that is cured through a crosslinking reaction upon irradiation with active rays (also called active energy rays) such as ultraviolet rays and electron beams. As the actinic radiation curable resin, a component containing a monomer having an ethylenically unsaturated double bond is preferably used, and an actinic radiation curable resin layer is formed by curing by irradiation with actinic radiation such as ultraviolet rays or electron beams. The Typical examples of the actinic radiation curable resin include an ultraviolet curable resin and an electron beam curable resin, but a resin curable by ultraviolet irradiation is particularly excellent in mechanical film strength (abrasion resistance, pencil hardness). It is preferable from the point. Examples of the ultraviolet curable resin include an ultraviolet curable acrylate resin, an ultraviolet curable urethane acrylate resin, an ultraviolet curable polyester acrylate resin, an ultraviolet curable epoxy acrylate resin, an ultraviolet curable polyol acrylate resin, and an ultraviolet curable resin. A curable epoxy resin or the like is preferably used, and among them, an ultraviolet curable acrylate resin or an ultraviolet curable urethane acrylate resin is preferable.

  As the ultraviolet curable acrylate resin, a polyfunctional acrylate is preferable. The polyfunctional acrylate is preferably selected from the group consisting of pentaerythritol polyfunctional acrylate, dipentaerythritol polyfunctional acrylate, pentaerythritol polyfunctional methacrylate, and dipentaerythritol polyfunctional methacrylate. Here, the polyfunctional acrylate is a compound having two or more acryloyloxy groups or methacryloyloxy groups in the molecule. Examples of the polyfunctional acrylate monomer include ethylene glycol diacrylate, diethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, and tetramethylolmethane triacrylate. , Tetramethylolmethane tetraacrylate, pentaglycerol triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tri / tetraacrylate, ditrimethylolpropane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol tetraacrylate, glycerol triacrylate relay , Dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tris (acryloyloxyethyl) isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, 1,6-hexanediol di Methacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, tetramethylolmethane trimethacrylate, tetramethylolmethane tetramethacrylate, pentaglycerol trimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pen Pentaerythritol tetramethacrylate, glycerol trimethacrylate, dipentaerythritol trimethacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol penta methacrylate, dipentaerythritol hexa methacrylate, etc. isocyanurate derivatives of the active energy ray-curable are preferably exemplified. From the object effect of the present invention, the hard coat layer according to the present invention preferably contains an active energy ray-curable isocyanurate derivative.

  The active energy ray-curable isocyanurate derivative is not particularly limited as long as it is a compound having a structure in which one or more ethylenically unsaturated groups are bonded to an isocyanuric acid skeleton. A compound having three or more ethylenically unsaturated groups and one or more isocyanurate rings in the same molecule shown is preferable from the viewpoint of the object effect of the present invention. The kind of ethylenically unsaturated group is an acryloyl group, a methacryloyl group, a styryl group, and a vinyl ether group, more preferably a methacryloyl group or an acryloyl group, and particularly preferably an acryloyl group.

In the formula, L ² is a divalent linking group, preferably a substituted or unsubstituted alkyleneoxy group or polyalkyleneoxy group having 4 or less carbon atoms in which a carbon atom is bonded to the isocyanurate ring, Particularly preferred are alkyleneoxy groups, which may be the same or different. R ² represents a hydrogen atom or a methyl group, and may be the same or different. Although the specific compound shown by General formula (1) is shown below, it is not restricted to these.

  Examples of the other compounds include isocyanuric acid diacrylate compounds, and isocyanuric acid ethoxy-modified diacrylates represented by the following general formula (2) are preferable.

  Other examples include ε-caprolactone-modified active energy ray-curable isocyanurate derivatives, specifically, compounds represented by the following general formula (3).

The functional groups represented by the following a, b, and c are attached to the positions of R _{1 to} R _{3 in} the above chemical structural formula, and at least one of R _{1 to} R ₃ is a functional group of b.

a: —H or — (CH ₂ ) _n —OH (n = 1 to 10, preferably n = 2 to 6)
b: — (CH ₂ ) _n —O— (COC ₅ H ₁₀ ) _m —COCH═CH ₂ (n = 1 to 10, preferably n = 2 to 6, m = 2 to 8)
c: — (CH ₂ ) _n —O—R (R is a (meth) acryloyl group, n = 1 to 10, preferably n = 2 to 6)
Although the specific compound shown by General formula (3) is shown below, it is not restricted to these.

  As a commercial item of an isocyanuric acid triacrylate compound, Shin-Nakamura Chemical Co., Ltd. A-9300 etc. are mentioned, for example. As a commercial item of an isocyanuric acid diacrylate compound, Toagosei Co., Ltd. Aronix M-215 etc. are mentioned, for example. Examples of the mixture of the isocyanuric acid triacrylate compound and the isocyanuric acid diacrylate compound include Aronix M-315 and Aronix M-313 manufactured by Toagosei Co., Ltd. As the ε-caprolactone-modified active energy ray-curable isocyanurate derivative, A-9300-1CL manufactured by Shin-Nakamura Chemical Co., Ltd., which is ε-caprolactone-modified tris- (acryloxyethyl) isocyanurate, manufactured by Toagosei Co., Ltd. Examples include, but are not limited to, Aronix M-327.

  As these commercial products, Adekaoptomer N series, Sun Rad H-601, RC-750, RC-700, RC-600, RC-500, RC-611, RC-612 (manufactured by Sanyo Chemical Industries, Ltd.) , Aronix M-6100, M-8030, M-8060, Aronix M-215, Aronix M-315, Aronix M-313, Aronix M-327 (manufactured by Toagosei Co., Ltd.), NK-ester A-TMM-3L , NK-ester AD-TMP, NK-ester ATM-35E, NK ester A-DOG, NK ester A-IBD-2E, A-9300, A-9300-1CL (Shin Nakamura Chemical Co., Ltd.), PE- 3A (Kyoeisha Chemical) etc. are mentioned.

  Examples of the ultraviolet curable urethane acrylate resin include, for example, a polyurethane obtained by reacting an alcohol, a polyol, and / or a hydroxyl group-containing compound such as a hydroxyl group-containing acrylate and an isocyanate or, if necessary, these reactions. It is obtained by esterifying a compound with (meth) acrylic acid. More specifically, it is an addition reaction product of polyisocyanate and an acrylate having one hydroxy group and one or more (meth) acryloyl groups in one molecule. Examples of the polyisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 4,4 ' A compound having two isocyanate groups bonded to an alicyclic hydrocarbon such as aromatic isocyanate such as diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, norbornane diisocyanate, 1,4-cyclohexane diisocyanate (hereinafter referred to as alicyclic diisocyanate and A compound having two isocyanate groups bonded to an aliphatic hydrocarbon such as trimethylene diisocyanate and hexamethylene diisocyanate (hereinafter referred to as aliphatic diisocyanate). Abbreviated as sulphonate.) Phenylene diisocyanate, aromatic diisocyanates such as toluene diisocyanate, and aromatic aliphatic diisocyanates such as xylylene diisocyanate. These polyisocyanates can be used alone or in combination of two or more, and are preferably aliphatic diisocyanates and alicyclic diisocyanates. Of these, isophorone diisocyanate, norbornane diisocyanate, toluene diisocyanate and hexamethylene diisocyanate are preferred. Examples of the acrylate having one hydroxy group and one or more (meth) acryloyl groups in one molecule include trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth). Examples include polyacrylates of polyvalent hydroxy group-containing compounds such as acrylates, addition products of these polyacrylates and ε-caprolactone, addition products of these polyacrylates and alkylene oxides, and epoxy acrylates. It is done. The acrylate having one hydroxy group and one or more (meth) acryloyl groups in one molecule can be used alone or in combination of two or more.

  Of the acrylates having one hydroxy group and one or more (meth) acryloyl groups in one molecule, acrylates having one hydroxy group and three to five (meth) acryloyl groups in one molecule are preferred. Examples of such acrylates include pentaerythritol triacrylate and dipentaerythritol pentaacrylate.

  Specific products of the ultraviolet curable urethane acrylate resin include: Nippon Synthetic Chemical Industry Co., Ltd., Shikou UV-1700B, UV-6300B, UV-7600B, UV-7630B, UV-7630B, UV-7640B, Kyoeisha Chemical Co., Ltd. Company-made, UA-306H, UA-306T, UA-306I, UA-510H, Shin-Nakamura Chemical Co., Ltd., NK Oligo UA-1100H, NK Oligo UA-53H, NK Oligo UA-33H, NK Oligo UA-15HA Etc.

  The viscosity of the actinic radiation curable resin can be measured using a B-type viscometer under the condition of 25 ° C. while the resin is stirred and mixed with a disper. A monofunctional acrylate may also be used.

  Monofunctional acrylates include isobornyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, isostearyl acrylate, benzyl acrylate, ethyl carbitol acrylate, phenoxyethyl acrylate, lauryl acrylate, isooctyl acrylate, tetrahydrofurfuryl acrylate, behenyl Examples include acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and cyclohexyl acrylate. Such monofunctional acrylates can be obtained from Nippon Kasei Kogyo Co., Ltd., Shin-Nakamura Chemical Co., Ltd., Osaka Organic Chemical Co., Ltd., etc.

  When using a monofunctional acrylate, it is preferable to contain in the range of polyfunctional acrylate: monofunctional acrylate = 80: 20-98: 2 by the mass ratio of polyfunctional acrylate and monofunctional acrylate.

(Photopolymerization initiator)
The hard coat layer preferably contains a photopolymerization initiator to accelerate the curing of the actinic radiation curable resin. The amount of the photopolymerization initiator is preferably contained in a mass ratio in the range of photopolymerization initiator: active ray curable resin = 20: 100 to 0.01: 100. Specific examples of the photopolymerization initiator include alkylphenone series, acetophenone, benzophenone, hydroxybenzophenone, Michler ketone, α-amyloxime ester, thioxanthone and the like, and derivatives thereof. In particular, it is not limited to these.

  A commercial item may be used for such a photoinitiator, for example, Irgacure 184, Irgacure 907, Irgacure 651, etc. by BASF Japan Ltd. are mentioned as a preferable example.

(Conductive agent)
The hard coat layer may contain a conductive agent in order to impart antistatic properties. Preferred conductive agents include metal oxide particles or π-conjugated conductive polymers. An ionic liquid is also preferably used as the conductive compound.

(Additive)
For the hard coat layer, from the viewpoint of controlling the difference (θ _Δ ) in water contact angle before and after the alkali treatment within the above range, a silicone surfactant, a fluorine surfactant, an anionic surfactant, and fluorine-siloxane are used. You may contain additives, such as a graft compound, a fluorine-type compound, and an acrylic copolymer. Moreover, you may contain the compound in the range whose HLB value is 3-18. By adjusting the type and amount of these additives, water repellency can be controlled, and θ _Δ can be easily controlled within the above range.

  The HLB value is Hydrophile-Lipophile-Balance, hydrophilic-lipophilic-balance, and is a value indicating the hydrophilicity or lipophilicity of a compound. The smaller the HLB value, the higher the lipophilicity, and the higher the value, the higher the hydrophilicity. Further, the HLB value in the present invention can be obtained by the following calculation formula.

HLB = 7 + 11.7Log (Mw / Mo)
In the formula, Mw represents the molecular weight of the hydrophilic group, Mo represents the molecular weight of the lipophilic group, and Mw + Mo = M (molecular weight of the compound). Specific examples of the compound having an HLB value in the range of 3 to 18 are listed below, but the present invention is not limited thereto. Figures in parentheses indicate HLB values.

  Made by Kao Corporation: Emulgen 102KG (6.3), Emulgen 103 (8.1), Emulgen 104P (9.6), Emulgen 105 (9.7), Emulgen 106 (10.5), Emulgen 108 (12. 1), Emulgen 109P (13.6), Emulgen 120 (15.3), Emulgen 123P (16.9), Emulgen 147 (16.3), Emulgen 210P (10.7), Emulgen 220 (14.2) , Emulgen 306P (9.4), Emulgen 320P (13.9), Emulgen 404 (8.8), Emulgen 408 (10.0), Emulgen 409PV (12.0), Emulgen 420 (13.6), Emulgen 430 (16.2), Emulgen 705 (10.5), Emulgen 707 (12.1), Emulgen 7 9 (13.3), Emulgen 1108 (13.5), Emulgen 1118S-70 (16.4), Emulgen 1135S-70 (17.9), Emulgen 2020G-HA (13.0), Emulgen 2025G (15. 7), Emulgen LS-106 (12.5), Emulgen LS-110 (13.4), Emulgen LS-114 (14.0), manufactured by Nissin Chemical Industry Co., Ltd .: Surfynol 104E (4), Surfynol 104H (4), Surfinol 104A (4), Surfinol 104BC (4), Surfinol 104DPM (4), Surfinol 104PA (4), Surfinol 104PG-50 (4), Surfinol 104S (4), Surfi Knoll 420 (4), Surfynol 440 (8), Surfynol 46 (13), Surfinol 485 (17), Surfinol SE (6), manufactured by Shin-Etsu Chemical Co., Ltd .: X-22-4272 (7), X-22-6266 (8), KF-351 (12) , KF-352 (7), KF-353 (10), KF-354L (16), KF-355A (12), KF-615A (10), KF-945 (4), KF-618 (11), KF-6011 (12), KF-6015 (4), and KF-6004 (5). Examples of the silicone surfactant include polyether-modified silicone, and the KF series manufactured by Shin-Etsu Chemical Co., Ltd. can be used. Examples of the acrylic copolymer include commercially available compounds such as BYK-350 and BYK-352 manufactured by BYK Japan. Examples of the fluorosurfactant include Megafac RS series manufactured by DIC Corporation, Megafac F-444 Megafac F-556, and the like. The fluorine-siloxane graft compound refers to a compound of a copolymer obtained by grafting polysiloxane and / or organopolysiloxane containing siloxane and / or organosiloxane alone on at least a fluorine-based resin. Such a fluorine-siloxane graft compound can be prepared by a method as described in Examples described later. Or as a commercial item, Fuji Chemical Industries Ltd. ZX-022H, ZX-007C, ZX-049, ZX-047-D etc. can be mentioned. Moreover, as a fluorine-type compound, Daikin Industries Ltd. OPTOOL DSX, OPTOOL DAC, etc. can be mentioned. These components are preferably added in the range of 0.005 parts by mass or more and 5 parts by mass or less with respect to the solid component in the hard coat composition.

(UV absorber)
A hard-coat layer may further contain the ultraviolet absorber demonstrated by the cellulose-ester film mentioned later. As a structure of the film in the case of containing the ultraviolet absorber, when it is constituted by two or more layers, it is preferable to contain the ultraviolet absorber in the hard coat layer in contact with the cellulose ester film.

  The content of the ultraviolet absorber is preferably in the range of mass ratio and ultraviolet absorber: hard coat layer constituting resin = 0.01: 100 to 10: 100. When two or more layers are provided, the thickness of the hard coat layer in contact with the cellulose ester film is preferably in the range of 0.05 to 2 μm. Two or more layers may be formed as a simultaneous multilayer. The simultaneous multi-layer is to form a hard coat layer by applying two or more hard coat layers on a base material without going through a drying step. In order to laminate the second hard coat layer on the first hard coat layer without a drying process, the layers are stacked one after another by an extrusion coater or simultaneously by a slot die having a plurality of slits. Can be done.

(solvent)
The hard coat layer is formed by diluting the above-described components forming the hard coat layer with a solvent that swells or partially dissolves the cellulose ester film, and is applied onto the cellulose film by the following method and dried. It is preferable to provide a hard coat layer by curing.

  As the solvent, ketone (methyl ethyl ketone, acetone, etc.) and / or acetate ester (methyl acetate, ethyl acetate, butyl acetate, etc.), alcohol (ethanol, methanol), propylene glycol monomethyl ether, cyclohexanone, methyl isobutyl ketone, etc. are preferable. The coating amount of the hard coat layer is suitably in the range of 0.1 to 40 μm, preferably in the range of 0.5 to 30 μm, as the wet film thickness. The dry film thickness is in the range of 0.01 to 20 μm, preferably in the range of 0.5 to 10 μm. More preferably, it is the range of 0.5-5 micrometers.

  As a method for applying the hard coat layer, known methods such as a gravure coater, a dip coater, a reverse coater, a wire bar coater, a die coater, and an ink jet method can be used.

(Hard coat layer forming method)
After applying the hard coat layer composition, it may be dried and cured by irradiation with active rays (also referred to as UV curing treatment), and if necessary, heat treatment may be performed after the UV curing treatment. The heat treatment temperature after the UV curing treatment is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and particularly preferably 120 ° C. or higher. By performing the heat treatment after the UV curing treatment at such a high temperature, a hard coat layer having excellent film strength can be obtained.

  Drying is preferably performed by a high-temperature treatment in which the temperature in the decreasing rate drying section is 90 ° C. or higher. More preferably, the temperature in the decreasing rate drying section is 90 ° C. or higher and 125 ° C. or lower. By setting the temperature of the rate-decreasing drying section to a high temperature treatment, convection occurs in the coating resin during the formation of the hard coat layer, and as a result, irregular surface roughness tends to appear on the hard coat layer surface, which will be described later. It is easy to control the arithmetic average roughness Ra.

  In general, it is known that the drying process changes from a constant state to a gradually decreasing state when drying starts. The decreasing section is called the decreasing rate drying section. In the constant rate drying section, the amount of heat flowing in is all consumed for solvent evaporation on the coating film surface, and when the solvent on the coating film surface decreases, the evaporation surface moves from the surface to the inside and enters the decreasing rate drying section. Thereafter, the temperature of the coating film surface rises and approaches the hot air temperature, so that the temperature of the actinic radiation curable resin composition rises, the resin viscosity decreases, and the fluidity increases.

  As a light source for UV curing treatment, any light source that generates ultraviolet rays can be used without limitation. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used.

The irradiation conditions vary depending on individual lamps, irradiation of actinic rays is generally within the range of 50~1000mJ / cm ^2, preferably in the range of 50 to 300 mJ / cm ^2. In the UV curing treatment, oxygen removal (for example, replacement with an inert gas such as nitrogen purge) can be performed to prevent reaction inhibition by oxygen. The cured state of the surface can be controlled by adjusting the removal amount of the oxygen concentration. This makes it possible to control the presence state of the additive on the hard coat layer surface, and as a result, it is easy to control _θΔ within the above range. When irradiating actinic radiation, it is preferably performed while applying tension in the film transport direction, and more preferably while applying tension in the width direction. The tension to be applied is preferably 30 to 300 N / m. The method for applying the tension is not particularly limited, and the tension may be applied in the conveying direction on the back roller, or the tension may be applied in the width direction or biaxial direction by a tenter. Thereby, a film having further excellent flatness can be obtained.

(Surface shape)
The arithmetic average roughness Ra (JIS B0601: 2001) of the hard coat layer is preferably in the range of 2 to 100 nm, particularly preferably in the range of 5 to 80 nm. By setting the arithmetic average roughness Ra within the above range, the effects of the present invention can be suitably obtained even after a more severe vibration test.

  The height of the protrusion shape for obtaining the arithmetic average roughness Ra is preferably in the range of 2 nm to 4 μm. The width of the protrusion shape is in the range of 50 nm to 300 μm, and preferably in the range of 50 nm to 100 μm.

  The 10-point average roughness Rz of the hard coat layer is 10 times or less of the centerline average roughness Ra, and the average mountain valley distance Sm is preferably 5 to 150 μm, more preferably 20 to 100 μm, and the height of the protrusion from the deepest part of the unevenness. Preferably, the standard deviation of the mean valley distance Sm with respect to the center line is 20 μm or less, and the surface with the inclination angle of 0 to 5 degrees is preferably 10% or more. The arithmetic average roughness Ra, Sm, Rz described above is a value measured with an optical interference surface roughness meter (manufactured by ZYGO, NewView) in accordance with JIS B0601: 2001.

(Haze)
The haze of the hard coat film is preferably in the range of 0.2 to 10% from the visibility when used in an image display device. Haze can be measured according to JIS-K7105 and JIS K7136.

(hardness)
The hard coat film of the present invention has a pencil hardness, which is an index of hardness, of HB or more, more preferably H or more. If it is more than HB, it is hard to be damaged in the polarizing plate forming step. The pencil hardness is determined by conditioning the prepared optical film at a temperature of 23 ° C. and a relative humidity of 55% for 2 hours or more, and then using a test pencil specified by JIS S6006 under a load of 500 g, It is the value which measured the functional layer in accordance with the pencil hardness evaluation method prescribed | regulated by JISK5400.

  Next, the cellulose ester film according to the present invention will be described.

<Cellulose ester film>
The cellulose ester film which is the base material of the hard coat film according to the present invention and the cellulose ester film bonded to the back side of the polarizing plate will be described.

  Examples of the cellulose ester film (hereinafter also referred to as cellulose acetate film) include a triacetyl cellulose film, a cellulose acetate propionate film, a cellulose diacetate film, and a cellulose acetate butyrate film. The cellulose ester film may be used in combination with polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate resins, polyethylene resins, polypropylene resins, norbornene resins, fluororesins, and cycloolefin polymers. Examples of the commercially available cellulose ester film include Konica Minoltak KC8UX, KC4UX, KC8UY, KC4UY, KC6UA, KC4UA, KC4UE and KC4UZ (manufactured by Konica Minolta Advanced Layer Co., Ltd.). The refractive index of the cellulose ester film is preferably 1.45 to 1.55. The refractive index can be measured according to JIS K7142-2008.

(Cellulose ester resin)
The cellulose ester resin (hereinafter also referred to as cellulose ester) is preferably a lower fatty acid ester of cellulose. The lower fatty acid in the lower fatty acid ester of cellulose means a fatty acid having 6 or less carbon atoms. For example, cellulose acetate, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, etc. Further, mixed fatty acid esters such as cellulose acetate butyrate can be used.

  Among these, cellulose fatty acid esters particularly preferably used are cellulose diacetate, cellulose triacetate, and cellulose acetate propionate. These cellulose esters can be used alone or in combination.

  Cellulose diacetate preferably has an average degree of acetylation (amount of bound acetic acid) in the range of 51.0 to 56.0%. Examples of commercially available products include L20, L30, L40, and L50 manufactured by Daicel Corporation, and Ca398-3, Ca398-6, Ca398-10, Ca398-30, and Ca394-60S manufactured by Eastman Chemical Japan Co., Ltd. .

  The cellulose triacetate preferably has an average degree of acetylation (bound acetic acid amount) of 54.0 to 62.5%, and more preferably cellulose triacetate having an average degree of acetylation of 58.0 to 62.5%. is there.

  As the cellulose triacetate, a cellulose triacetate A having a number average molecular weight (Mn) of 125,000 or more and less than 155000, a weight average molecular weight (Mw) of 265,000 or more and less than 310,000, and Mw / Mn of 1.9 to 2.1. The degree of acetyl group substitution is in the range of 2.75 to 2.90, the number average molecular weight (Mn) is 155000 or more and less than 180000, Mw is 290000 or more and less than 360,000, and Mw / Mn is 1.8 to 2.0. It is preferable to contain cellulose triacetate B in the range.

  Cellulose acetate propionate has an acyl group having 2 to 4 carbon atoms as a substituent, and when the substitution degree of the acetyl group is X and the substitution degree of the propionyl group is Y, the following formulas (I) and ( Those satisfying II) are preferred.

Formula (I) 2.6 ≦ X + Y ≦ 3.0
Formula (II) 0 ≦ X ≦ 2.5
Among them, it is preferable that 1.9 ≦ X ≦ 2.5 and 0.1 ≦ Y ≦ 0.9.

  The method for measuring the substitution degree of the acyl group can be measured according to ASTM-D817-96.

  The number average molecular weight (Mn) and molecular weight distribution (Mw) of the cellulose ester can be measured using high performance liquid chromatography. The measurement conditions are as follows.

Solvent: Methylene chloride Column: Shodex K806, K805, K803G
(Used by connecting three Showa Denko Co., Ltd.)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (GL Science Co., Ltd.)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0 ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corp.) Mw = 100000 to 500 samples were used. The 13 samples are preferably used at approximately equal intervals.

(Thermoplastic acrylic resin)
The cellulose ester film may be used in combination with a thermoplastic acrylic resin. When using together, the mass ratio of the thermoplastic acrylic resin and the cellulose ester resin is preferably in the range of thermoplastic acrylic resin: cellulose ester resin = 95: 5 to 50:50.

  Acrylic resin also includes methacrylic resin. Although it does not restrict | limit especially as an acrylic resin, What consists of the range of 50-99 mass% of methyl methacrylate units, and the range of 1-50 mass% of other monomer units copolymerizable with this is preferable. . Other monomers that can be copolymerized include alkyl methacrylates having 2 to 18 carbon atoms, alkyl acrylates having 1 to 18 carbon atoms, acrylic acid, methacrylic acid, and the like. Saturated acids, maleic acid, fumaric acid, unsaturated group-containing divalent carboxylic acids such as itaconic acid, aromatic vinyl compounds such as styrene and α-methylstyrene, α, β-unsaturated nitriles such as acrylonitrile and methacrylonitrile, Maleic anhydride, maleimide, N-substituted maleimide, glutaric anhydride and the like may be mentioned, and these may be used alone or in combination of two or more.

  Among these, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like are preferable from the viewpoint of thermal decomposition resistance and fluidity of the copolymer, and methyl acrylate and n -Butyl acrylate is particularly preferably used. Moreover, it is preferable that a weight average molecular weight (Mw) is 80000-500000, More preferably, it exists in the range of 110000-500000.

  The weight average molecular weight of the acrylic resin can be measured by gel permeation chromatography. Commercially available acrylic resins include, for example, Delpet 60N, 80N (Asahi Kasei Chemicals Corporation), Dialnal BR52, BR80, BR83, BR85, BR88 (Mitsubishi Rayon Co., Ltd.), KT75 (Electrochemical Industry Co., Ltd.) )) And the like. Two or more acrylic resins can be used in combination.

(Fine particles)
The cellulose ester film according to the present invention has, for example, acrylic particles, silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, kaolin, talc, calcined calcium silicate, and hydrated calcium silicate in order to improve handleability. It is preferable to contain a matting agent such as inorganic fine particles such as aluminum silicate, magnesium silicate and calcium phosphate and a crosslinked polymer. The acrylic particles are not particularly limited, but are preferably multi-layered acrylic granular composites. Among these, silicon dioxide is preferable in that the haze of the cellulose ester film can be reduced. The primary average particle diameter of the fine particles is preferably 20 nm or less, more preferably in the range of 5 to 16 nm, and particularly preferably in the range of 5 to 12 nm.

  The cellulose acetate film according to the present invention preferably contains an ester or sugar ester represented by the following general formula (X) from the viewpoint of improving the dimensional stability performance under environmental changes. First, the ester represented by the general formula (X) will be described.

Formula (X) B- (GA) _n -GB
(Wherein B is a hydroxy group or carboxylic acid residue, G is an alkylene glycol residue having 2 to 12 carbon atoms, an aryl glycol residue having 6 to 12 carbon atoms, or an oxyalkylene glycol residue having 4 to 12 carbon atoms) , A represents an alkylene dicarboxylic acid residue having 4 to 12 carbon atoms or an aryl dicarboxylic acid residue having 6 to 12 carbon atoms, and n represents an integer of 1 or more.)
In the general formula (X), as the alkylene glycol component having 2 to 12 carbon atoms, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2,2-diethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3-methyl -1,5-pentanediol 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl There are 1,3-hexanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol, and the like. Used as a mixture of seeds and more. In particular, an alkylene glycol having 2 to 12 carbon atoms is particularly preferable because of excellent compatibility with cellulose acetate. Examples of the aryl glycol component having 6 to 12 carbon atoms include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol, and the like, and these glycols can be used as one kind or a mixture of two or more kinds.

  Examples of the oxyalkylene glycol component having 4 to 12 carbon atoms include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. These glycols may be used alone or as a mixture of two or more. Can be used as Examples of the alkylene dicarboxylic acid component having 4 to 12 carbon atoms include succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, and the like. Used as a mixture of seeds and more. Examples of the arylene dicarboxylic acid component having 6 to 12 carbon atoms include phthalic acid, terephthalic acid, isophthalic acid, 1,5-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, and the like. Although the specific example (compound X-1-compound X-17) of a compound represented by general formula (X) below is shown, it is not limited to this.

  Next, the sugar ester will be described. The sugar ester is an ester other than cellulose ester, and is a compound obtained by esterifying all or part of the OH group of a sugar such as the following monosaccharide, disaccharide, trisaccharide or oligosaccharide. Examples of the sugar include glucose, galactose, mannose, fructose, xylose, arabinose, lactose, sucrose, nystose, 1F-fructosyl nystose, stachyose, maltitol, lactitol, lactulose, cellobiose, maltose, cellotriose, maltotriose, raffinose And kestose. In addition, gentiobiose, gentiotriose, gentiotetraose, xylotriose, galactosyl sucrose, and the like are also included. Among these compounds, compounds having a furanose structure and / or a pyranose structure are particularly preferable. Among these, sucrose, kestose, nystose, 1F-fructosyl nystose, stachyose and the like are preferable, and sucrose is more preferable. As oligosaccharides, maltooligosaccharides, isomaltooligosaccharides, fructooligosaccharides, galactooligosaccharides, and xylo-oligosaccharides can also be preferably used.

  The monocarboxylic acid used for esterifying the sugar is not particularly limited, and known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid and the like can be used. The carboxylic acid to be used may be one kind or a mixture of two or more kinds. Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, undecylic acid, lauric acid , Saturated fatty acids such as tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melicic acid, and laccelic acid, Examples include unsaturated fatty acids such as undecylenic acid, oleic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid and octenoic acid. Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, or derivatives thereof. Examples of preferred aromatic monocarboxylic acids include benzoic acid, aromatic monocarboxylic acids having an alkyl group or alkoxy group introduced into the benzene ring of benzoic acid, cinnamic acid, benzylic acid, biphenylcarboxylic acid, naphthalenecarboxylic acid, tetralin An aromatic monocarboxylic acid having two or more benzene rings such as carboxylic acid, or a derivative thereof can be mentioned, and more specifically, xylic acid, hemelic acid, mesitylene acid, planicylic acid, γ-isojurylic acid, Julylic acid, mesitic acid, α-isoduric acid, cumic acid, α-toluic acid, hydroatropic acid, atropic acid, hydrocinnamic acid, salicylic acid, o-, m, p-anisic acid, creosote acid, o- p-homosalicylic acid, o-pyrocatechuic acid, β-resorcylic acid, vanillic acid, isovanillic acid, veratrum acid o- veratric acid, gallic acid, asarone acid, mandelic acid, homoanisic acid, homovanillic acid, homoveratric acid, o- homoveratric acid, Futaron acid, can be mentioned p- coumaric acid, especially benzoic acid. Among the esters, acetyl compounds having an acetyl group introduced by esterification are preferred. Although the specific example of the sugar ester which can be used for this invention below is shown, it is not limited to these.

  The sugar ester is preferably a compound represented by the general formula (Y). Below, the compound shown by general formula (Y) is demonstrated.

（式中、Ｒ_１〜Ｒ_８は、水素原子、置換若しくは無置換の炭素数２〜２２のアルキルカルボニル基、あるいは、置換又は無置換の炭素数２〜２２のアリールカルボニル基を表し、Ｒ_１〜Ｒ_８は、同じであっても、異なっていてもよい。）
以下に一般式（Ｙ）で示される化合物をより具体的（化合物Ｙ−１〜化合物Ｙ−２３）に示すが、これらに限定はされない。なお、下表において平均置換度が８．０未満の場合、Ｒ_１〜Ｒ_８のうちのいずれかは水素原子を表す。

(Wherein R _{1 to} R ₈ represent a hydrogen atom, a substituted or unsubstituted alkylcarbonyl group having 2 to 22 carbon atoms, or a substituted or unsubstituted arylcarbonyl group having 2 to 22 carbon atoms; R ₁ to R ₈ may be the same or different.)
Although the compound shown with general formula (Y) below is shown more concretely (compound Y-1-compound Y-23), it is not limited to these. In the following table, when the average degree of substitution is less than 8.0, any one of R _{1 to} R ₈ represents a hydrogen atom.

  The substitution degree distribution can be adjusted to the desired substitution degree by adjusting the esterification reaction time or mixing compounds having different substitution degrees.

  The ester or sugar ester represented by the general formula (X) is preferably contained in the cellulose acetate film in the range of 1 to 30% by mass, more preferably in the range of 5 to 25% by mass. It is especially preferable to make it contain in the range of -20 mass%.

(Other additives)
[Plasticizer]
The cellulose acetate film according to the present invention may contain a plasticizer as necessary.

  The plasticizer is not particularly limited, but is a polyvalent carboxylic ester plasticizer, glycolate plasticizer, phthalate ester plasticizer, phosphate ester plasticizer, and polyhydric alcohol ester plasticizer, acrylic. A plasticizer etc. are mentioned. In these, an acrylic plasticizer is preferable from the point which can control a cellulose-ester film to the retardation value mentioned later.

  The polyhydric alcohol ester plasticizer is a plasticizer comprising an ester of a divalent or higher aliphatic polyhydric alcohol and a monocarboxylic acid, and preferably has an aromatic ring or a cycloalkyl ring in the molecule. Preferably it is a 2-20 valent aliphatic polyhydric alcohol ester. Preferable specific examples of the polyhydric alcohol ester plasticizer include compounds described in paragraphs [0058] to [0061] of JP-A-2006-113239.

  The glycolate plasticizer is not particularly limited, but alkylphthalylalkyl glycolates can be preferably used. Examples of alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl Glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycol Butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl methyl glycolate, octyl phthalate Ethyl glycolate, and the like.

  Examples of the phthalate ester plasticizer include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.

  Examples of the phosphate ester plasticizer include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate and the like.

  The polyvalent carboxylic acid ester plasticizer is a compound composed of an ester of a divalent or higher, preferably divalent to -20 valent polyvalent carboxylic acid and an alcohol. Specific examples include triethyl citrate, tributyl citrate, acetyl triethyl citrate (ATEC), acetyl tributyl citrate (ATBC), benzoyl tributyl citrate, acetyl triphenyl citrate, acetyl tribenzyl citrate, dibutyl tartrate, tartaric acid Examples include, but are not limited to, diacetyldibutyl, tributyl trimellitic acid, tetrabutyl pyromellitic acid, and the like.

  The acrylic plasticizer is preferably an acrylic polymer, and the acrylic polymer is preferably a homopolymer or copolymer of acrylic acid or alkyl methacrylate. Examples of the acrylate monomer include methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), butyl acrylate (n-, i-, s-, t-), pentyl acrylate ( n-, i-, s-), hexyl acrylate (n-, i-), heptyl acrylate (n-, i-), octyl acrylate (n-, i-), nonyl acrylate (n-, i-), myristyl acrylate (n-, i-), acrylic acid (2-ethylhexyl), acrylic acid (ε-caprolactone), acrylic acid (2-hydroxyethyl), acrylic acid (2-hydroxypropyl), acrylic Acid (3-hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), acrylic acid (2-methoxyethyl), acrylic acid 2-ethoxyethyl), etc., or the acrylic acid ester may include those obtained by changing the methacrylic acid ester. The acrylic polymer is a homopolymer or copolymer of the above-mentioned monomers, but the acrylic acid methyl ester monomer unit preferably has 30% by mass or more, and the methacrylic acid methyl ester monomer unit has 40% by mass or more. preferable. In particular, a homopolymer of methyl acrylate or methyl methacrylate is preferred.

  In addition, when making the cellulose acetate film which concerns on this invention contain the plasticizer mentioned above, it is preferable to make the usage-amount contain in the range of 1-50 mass% with respect to a cellulose acetate, The range of 5-35 mass% It is more preferable to make it contain, and it is especially preferable to make it contain in the range of 5-25 mass%.

(UV absorber)
The cellulose acetate film according to the present invention may contain an ultraviolet absorber. Since the ultraviolet absorber absorbs ultraviolet rays of 400 nm or less, durability can be improved. In particular, the ultraviolet absorber preferably has a transmittance of 10% or less at a wavelength of 370 nm, more preferably 5% or less, and still more preferably 2% or less. Specific examples of the ultraviolet absorber are not particularly limited. For example, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex salts, inorganic powders. Examples include the body.

  More specifically, for example, 5-chloro-2- (3,5-di-sec-butyl-2-hydroxylphenyl) -2H-benzotriazole, (2-2H-benzotriazol-2-yl) -6 -(Linear and side chain dodecyl) -4-methylphenol, 2-hydroxy-4-benzyloxybenzophenone, 2,4-benzyloxybenzophenone, etc. can be used. Commercially available products may be used. For example, TINUVIN such as TINUVIN 109, TINUVIN 171, TINUVIN 234, TINUVIN 326, TINUVIN 327, and TINUVIN 328 manufactured by BASF Japan Ltd. can be preferably used.

  Preferred ultraviolet absorbers are benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, and triazine ultraviolet absorbers, and particularly preferred are benzotriazole ultraviolet absorbers and benzophenone ultraviolet absorbers.

  In addition, a discotic compound such as a compound having a 1,3,5 triazine ring is also preferably used as the ultraviolet absorber. As the UV absorber, a polymer UV absorber can be preferably used, and a polymer type UV absorber is particularly preferably used.

  As a benzotriazole ultraviolet absorber, TINUVIN 109 (octyl-3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazole-2-) manufactured by BASF Japan Ltd., which is a commercial product, is available. Yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl] propionate), TINUVIN 928 (2 -(2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3,3-tetramethylbutyl) phenol) and the like can be used. As the triazine-based ultraviolet absorber, TINUVIN 400 (2- (4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl) -manufactured by BASF Japan Ltd., which is a commercial product, is available. Reaction product of 5-hydroxyphenyl and oxirane), TINUVIN 460 (2,4-bis [2-hydroxy-4-butoxyphenyl] -6- (2,4-dibutoxyphenyl) -1,3-5 Triazine), TINUVIN 405 (2- (2,4-dihydroxyphenyl) -4,6-bis- (2,4-dimethylphenyl) -1,3,5-triazine and (2-ethylhexyl) -glycidic acid ester Reaction products) and the like.

  The ultraviolet absorber is added by dissolving the ultraviolet absorber in an alcohol, such as methanol, ethanol, butanol or the like, an organic solvent such as methylene chloride, methyl acetate, acetone, dioxolane, or a mixed solvent thereof, and then becomes a film substrate. It may be added to the resin solution (dope) or directly during the dope composition. For an inorganic powder that does not dissolve in an organic solvent, a dissolver or a sand mill is used in the organic solvent and cellulose acetate to disperse and then added to the dope.

  The amount of the ultraviolet absorber used is preferably in the range of 0.5 to 10% by mass, more preferably in the range of 0.6 to 4% by mass with respect to the cellulose acetate film.

(Antioxidant)
The cellulose acetate film according to the present invention may further contain an antioxidant (deterioration inhibitor). The antioxidant has a role of delaying or preventing the cellulose acetate film from being decomposed by a residual solvent amount of halogen in the cellulose acetate film, phosphoric acid of a phosphoric acid plasticizer, or the like. As the antioxidant, hindered phenol compounds are preferably used. For example, 2,6-di-tert-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl). -4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3 5-triazine, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- 3,5-di-tert-butyl-4-hydroxyphenyl) propionate, N, N'-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3 5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate Etc. The addition amount of these compounds is preferably in the range of 1 to 10000 ppm, more preferably in the range of 10 to 1000 ppm by mass ratio with respect to the cellulose acetate film.

(Disadvantage)
The cellulose ester film preferably has a defect of 5 μm or more in diameter of 1 piece / 10 cm square or less. More preferably, it is 0.5 piece / 10 cm square or less, more preferably 0.1 piece / 10 cm square or less. Here, the diameter of the defect indicates the diameter when the defect is circular, and when the defect is not circular, the range of the defect is determined by observing with a microscope by the following method, and the maximum diameter (diameter of circumscribed circle) is determined.

  The range of the defect is the size of the shadow when the defect is observed with the transmitted light of the differential interference microscope when the defect is a bubble or a foreign object. When the defect is a change in the surface shape such as transfer of a roller scratch or an abrasion, the size can be confirmed by observing the defect with reflected light of a differential interference microscope.

  When the number of defects is greater than 1/10 cm square, for example, when the film is tensioned during processing in a later process, the film may break with the defects as a starting point, and productivity may decrease. Moreover, when the diameter of a defect becomes 5 micrometers or more, it can confirm visually by polarizing plate observation etc., and when used as an optical member, a bright spot may arise.

  Moreover, even when it cannot confirm visually, when a hard-coat layer is formed, a coating film cannot be formed uniformly and it may become a fault (coating omission). Here, the defect is a void in the film (foaming defect) generated due to the rapid evaporation of the solvent in the drying process of the solution casting, a foreign matter in the film forming stock solution, or a foreign matter mixed in the film forming. This refers to foreign matter (foreign matter defect) in the film. In addition, the base film preferably has a breaking elongation of at least one direction of 10% or more, more preferably 20% or more, in the measurement based on JIS-K7127-1999. The upper limit of the elongation at break is not particularly limited, but is practically about 250%. In order to increase the elongation at break, it is effective to suppress defects in the film caused by foreign matter and foaming.

(optical properties)
The cellulose ester film preferably has a total light transmittance of 90% or more, more preferably 93% or more. Moreover, as a realistic upper limit, it is about 99%. The haze value is preferably 2% or less, more preferably 1.5% or less. The total light transmittance and haze value can be measured according to JIS K7361 and JIS K7136.

  The in-plane retardation value Ro of the cellulose ester film is preferably in the range of 0 to 5 nm, and the retardation value Rth in the thickness direction is preferably in the range of −10 to 10 nm. Further, Rth is more preferably within a range of −5 to 5 nm.

  Ro and Rth are values defined by the following formulas (i) and (ii).

Formula _{(i) Ro = (n x} -n y) × d
Formula (ii) Rth = {(n _x + _ny ) / 2−n _z } × d
(Wherein, n _x is a refractive index in a slow axis direction of the cellulose ester film plane, n _y is the refractive index in the direction perpendicular to the slow axis in a cellulose ester film surface, the thickness of the n _z cellulose ester film (The refractive index in the direction, d represents the thickness (nm) of the cellulose ester film, respectively.)
The retardation can be determined at a wavelength of 590 nm under an environment of 23 ° C. and a relative humidity of 55% using, for example, KOBRA-21ADH (manufactured by Oji Scientific Instruments). By using the cellulose ester film controlled to the above retardation value, it is preferable from the viewpoint of excellent visibility when used in an image display device such as a touch panel or a liquid crystal display device. Retardation can be adjusted by the kind and addition amount of a plasticizer mentioned above, the film thickness of a cellulose ester film, stretching conditions, and the like.

(Film formation of cellulose ester film)
Next, although the example of the film forming method of a cellulose-ester film is demonstrated, it is not limited to this. As a method for producing a cellulose ester film, production methods such as an inflation method, a T-die method, a calendar method, a cutting method, a casting method, an emulsion method, a hot press method and the like can be used.

(Organic solvent)
The organic solvent useful for forming a resin solution (dope composition) when a cellulose ester film is produced by a solution casting method is limited as long as it dissolves a cellulose ester resin and other additives at the same time. Can be used. For example, as the chlorinated organic solvent, methylene chloride, as the non-chlorinated organic solvent, methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro- 2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol, etc. Can, methylene chloride, methyl acetate, ethyl acetate, may be used preferably acetone. The solvent is preferably a dope composition in which a cellulose ester resin and other additives are dissolved within a total range of 15 to 45% by mass.

[Solution casting film forming method]
In the solution casting film forming method, a step of preparing a dope by dissolving a resin and an additive in a solvent, a step of casting the dope on a belt-shaped or drum-shaped metal support, and drying the cast dope as a web It is carried out by a step of peeling off from the metal support, a step of stretching or maintaining the width, a step of further drying, and a step of winding up the finished cellulose ester film.

  As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used.

  The width of the cast can be in the range of 1-4 m. The surface temperature of the metal support in the casting step is set to −50 ° C. to a temperature at which the solvent boils and does not foam. A higher temperature is preferred because the web can be dried faster, but if it is too high, the web may foam or the flatness may deteriorate.

  A preferable support temperature is appropriately determined in the range of 0 to 100 ° C, and more preferably in the range of 5 to 30 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and peeled from the drum in a state containing a large amount of residual solvent. The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing warm air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use warm water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short.

  When using warm air, considering the temperature drop of the web due to the latent heat of vaporization of the solvent, while using warm air above the boiling point of the solvent, there may be cases where wind at a temperature higher than the target temperature is used while preventing foaming. .

  In particular, it is preferable to perform drying efficiently by changing the temperature of the support and the temperature of the drying air during the period from casting to peeling.

  In order for the cellulose ester film to obtain good planarity, the amount of residual solvent when peeling the web from the metal support is preferably in the range of 10 to 150% by mass, more preferably 20 to 40% by mass. The range or the range of 60 to 130% by mass, particularly preferably the range of 20 to 30% by mass or the range of 70 to 120% by mass. The amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Note that M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

  In the drying step of the cellulose ester film, the web is peeled off from the metal support and dried, and the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less, particularly preferably. It is the range of 0-0.01 mass%.

  In the film drying process, a roller drying method (a method in which webs are alternately passed through a plurality of rollers arranged above and below) and a method of drying while transporting the web by a tenter method are adopted.

  In the stretching step, the film can be sequentially or simultaneously stretched in the longitudinal direction (MD direction) and the width direction (TD direction) of the film. The draw ratios in the biaxial directions perpendicular to each other are preferably in the range of 1.0 to 2.0 times in the MD direction and 1.05 to 2.0 times in the TD direction, respectively. It is preferable to carry out in the range of 1.0 to 1.5 times in the direction and 1.05 to 2.0 times in the TD direction. For example, a method in which a circumferential speed difference is applied to a plurality of rollers, and the roller circumferential speed difference is used to stretch in the MD direction. Both ends of the web are fixed with clips and pins, and the interval between the clips and pins is widened in the traveling direction. And a method of stretching in the MD direction, a method of stretching in the transverse direction and stretching in the TD direction, a method of stretching the MD direction and the TD direction at the same time, and stretching in both directions.

  These width maintenance or width direction stretching in the film forming process is preferably performed by a tenter, and may be a pin tenter or a clip tenter.

  The film transport tension in the film forming process such as a tenter depends on the temperature, but is preferably in the range of 120 to 200 N / m, and more preferably in the range of 140 to 200 N / m. A range of 140 to 160 N / m is most preferred.

  When the glass transition temperature of the cellulose ester film is Tg, the stretching temperature is preferably in the range of (Tg-30) to (Tg + 100) ° C, more preferably in the range of (Tg-20) to (Tg + 80) ° C, and still more preferably ( The range is from Tg-5) to (Tg + 20) ° C.

  The Tg of the cellulose ester film can be controlled by the material type constituting the film and the ratio of the constituting materials. The Tg when the cellulose ester film is dried is preferably 110 ° C. or higher, more preferably 120 ° C. or higher. Especially preferably, it is 150 degreeC or more. The glass transition temperature is preferably 190 ° C. or lower, more preferably 170 ° C. or lower. The Tg of the cellulose ester film can be determined by the method described in JIS K7121. The stretching temperature is preferably 150 ° C. or more and the stretching ratio is 1.15 times or more because the surface is appropriately roughened. Roughening the surface of the cellulose ester film is preferable because it improves slipperiness and improves surface processability.

[Melt casting method]
The cellulose ester film may be formed by a melt casting film forming method. In the melt casting film forming method, a composition containing other additives such as a cellulose ester resin and a plasticizer is heated and melted to a temperature showing fluidity, and then a melt containing the fluid cellulose ester is cast. To do.

  In the melt casting film forming method, the melt extrusion method is preferable from the viewpoint of mechanical strength and surface accuracy. A plurality of raw materials used for melt extrusion are usually preferably kneaded and pelletized in advance.

  Pelletization may be performed by a known method. For example, dry cellulose ester, plasticizer, and other additives are fed to an extruder using a feeder, kneaded using a single or twin screw extruder, and extruded from a die into a strand. It can be done by water cooling or air cooling and cutting.

  The additives may be mixed before being supplied to the extruder, or may be supplied by individual feeders.

  A small amount of additives such as particles and antioxidants are preferably mixed in advance in order to mix uniformly.

  The extruder is preferably processed at a temperature as low as possible so that it can be pelletized so that the shearing force is suppressed and the resin does not deteriorate (molecular weight reduction, coloring, gel formation, etc.). For example, in the case of a twin screw extruder, it is preferable to rotate in the same direction using a deep groove type screw. From the uniformity of kneading, the meshing type is preferable.

  A film is formed using the pellets obtained as described above. Of course, the raw material powder can be directly fed to the extruder by a feeder without being pelletized to form a film as it is.

  Using a uniaxial or biaxial extruder, the pellets are melted at a temperature of about 200 to 300 ° C., filtered through a leaf disk type filter or the like to remove foreign matter, and then formed into a film from a T die. The cellulose ester film is formed by casting, nipping the film with a cooling roller and an elastic touch roller, and solidifying the film on the cooling roller.

  When introducing into the extruder from the supply hopper, it is preferable to prevent oxidative decomposition or the like under vacuum, reduced pressure, or inert gas atmosphere.

  The extrusion flow rate is preferably adjusted stably by introducing a gear pump or the like. Further, a stainless fiber sintered filter is preferably used as a filter used for removing foreign substances. The stainless steel fiber sintered filter is a united stainless steel fiber body that is intricately intertwined and compressed, and the contact points are sintered and integrated. The density of the fiber is changed depending on the thickness of the fiber and the amount of compression, and the filtration accuracy is improved. Can be adjusted.

  Additives such as plasticizers and particles may be mixed with the resin in advance, or may be kneaded in the middle of the extruder. In order to add uniformly, it is preferable to use a mixing apparatus such as a static mixer.

  The cellulose ester film temperature on the touch roller side when the cellulose ester film is nipped between the cooling roller and the elastic touch roller is preferably set to Tg or more (Tg + 110 ° C.) or less of the film. A known roller can be used as the roller having an elastic surface used for such purposes.

  The elastic touch roller is also called a pinching rotary body. A commercially available one can be used as the elastic touch roller.

  When peeling the cellulose ester film from the cooling roller, it is preferable to control the tension to prevent deformation of the film.

  Moreover, it is preferable to stretch | stretch the cellulose-ester film obtained by making it above by the said extending | stretching operation after passing the process which contact | connects a cooling roller.

  As a stretching method, a known roller stretching machine, a tenter or the like can be preferably used. The stretching temperature is preferably carried out in the temperature range of Tg to (Tg + 60) ° C. of the resin that usually constitutes the film.

  Before winding, the end may be slit and cut to the width to be the product, and knurling (embossing) may be applied to both ends to prevent sticking and scratching during winding. The knurling method can be performed by heating or pressurizing using a metal ring having an uneven pattern on the side surface. Since the cellulose ester film is deformed and cannot be used as a product, the clip holding portions at both ends of the film are usually cut out and reused.

(Physical properties of cellulose ester film)
The film thickness of the cellulose ester film in the present invention is in the range of 5 to 34 μm. The effect expression of the present invention can be obtained in a cellulose ester film having a film thickness in this range. Preferably, it exists in the range of 10-30 micrometers. The width of the cellulose ester film is preferably 1 to 4 m. If it exceeds 4 m, conveyance becomes difficult.

  Moreover, the length of a cellulose-ester film has the preferable range of 500-10000m, More preferably, it is the range of 1000-8000m. By setting it as the range of the said length, it is excellent in the processability in application | coating, such as a hard-coat layer, and the handleability of the cellulose-ester film itself.

  Moreover, arithmetic mean roughness Ra of a cellulose-ester film becomes like this. Preferably it is the range of 2-10 nm, More preferably, it is the range of 2-5 nm. The arithmetic average roughness Ra can be measured according to JIS B0601: 1994.

  The water contact angle before the alkali treatment of the cellulose ester film is generally in the range of 40 to 80 °, and preferably in the range of 50 to 70 °. Moreover, although the water contact angle after an alkali treatment is based also on the alkali processing conditions, the range of 10-60 degrees is common, Preferably it is the range of 20-60 degrees. The water contact angle is a value measured according to the method described in the method for measuring the water contact angle of the hard coat layer.

  It is presumed that the hard coat layer has a reduced contact angle with water due to the alkali treatment, and the contact angle with water with the cellulose ester film approaches, resulting in a laminated state of the hydrophilic layers and the expression effect of the present invention is obtained. ing.

  As an alkali treatment method, the cellulose ester film is immersed in an alkali solution, then washed with water and dried. Further, after the alkali treatment, neutralization in an acidic water step may be performed, followed by washing with water and drying.

  Examples of the alkaline solution include a potassium hydroxide solution and a sodium hydroxide solution, and the concentration of hydroxide ions is preferably in the range of 0.1 to 5 mol / L, and preferably 0.5 mol / L to 3 mol / L. More preferably, it is in the range. Furthermore, the temperature of the alkaline solution is preferably in the range of 25 to 90 ° C, more preferably in the range of 40 to 70 ° C. The alkali treatment time is in the range of 5 seconds to 5 minutes, preferably in the range of 30 seconds to 3 minutes.

<Other layers>
The hard coat film of the present invention can be provided with other layers such as an antireflection layer and a conductive layer.

<Antireflection layer>
The hard coat film according to the present invention can be used as an antireflection film having an external light antireflection function by coating an antireflection layer on the hard coat layer.

The antireflection layer is preferably laminated in consideration of the refractive index, the film thickness, the number of layers, the layer order, and the like so that the reflectance is reduced by optical interference. The antireflection layer is composed of a low refractive index layer having a lower refractive index than the protective film as the support, or a combination of a high refractive index layer and a low refractive index layer having a higher refractive index than the protective film as the support. Preferably it is. Particularly preferably, it is an antireflection layer composed of three or more refractive index layers. Three layers having different refractive indexes from the support side are divided into medium refractive index layers (high refractive index layers having a higher refractive index than the support). Are preferably laminated in the order of a layer having a lower refractive index) / a high refractive index layer / a low refractive index layer. Alternatively, an antireflection layer having a layer structure of four or more layers in which two or more high refractive index layers and two or more low refractive index layers are alternately laminated is also preferably used. As the layer structure, the following structure is conceivable, but is not limited thereto.
Cellulose ester film / hard coat layer / low refractive index layer cellulose ester film / hard coat layer / high refractive index layer / low refractive index layer cellulose ester film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index Layer hard coat layer / cellulose ester film / hard coat layer / low refractive index layer hard coat layer / cellulose ester film / hard coat layer / high refractive index layer / low refractive index layer hard coat layer / cellulose ester film / hard coat layer / Medium refractive index layer / High refractive index layer / Low refractive index layer Low refractive index layer / Hard coat layer / Cellulose ester film / Hard coat layer / Low refractive index layer (Low refractive index layer)
The low refractive index layer preferably contains silica-based fine particles, and the refractive index is preferably in the range of 1.30 to 1.45 when measured at 23 ° C. and a wavelength of 550 nm.

  The film thickness of the low refractive index layer is preferably in the range of 5 nm to 0.5 μm, more preferably in the range of 10 nm to 0.3 μm, and in the range of 30 nm to 0.2 μm. Most preferred.

  The composition for forming a low refractive index layer preferably contains at least one kind of particles having an outer shell layer and porous or hollow inside as silica-based fine particles. In particular, the particles having the outer shell layer and porous or hollow inside are preferably hollow silica-based fine particles.

  The composition for forming a low refractive index layer may contain an organosilicon compound represented by the following general formula (OSi-1), a hydrolyzate thereof, or a polycondensate thereof.

General formula (OSi-1): Si (OR) ₄
In the organic silicon compound represented by the general formula, R represents an alkyl group having 1 to 4 carbon atoms. Specifically, tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane and the like are preferably used.

  In addition, a silane coupling agent, a curing agent, a surfactant and the like may be added as necessary. Moreover, you may contain the compound which has a thermosetting and / or photocuring property which mainly contains the fluorine atom which contains a fluorine atom in 35-80 mass%, and contains a crosslinkable or polymeric functional group. Specifically, a fluorine-containing polymer or a fluorine-containing sol-gel compound is used. As the fluorine-containing polymer, for example, a hydrofluorinated monomer in addition to a hydrolyzate or dehydration condensate of a perfluoroalkyl group-containing silane compound [for example, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane] Examples thereof include fluorine-containing copolymers having units and cross-linking reactive units as constituent units. In addition, you may add a solvent, a silane coupling agent, a hardening | curing agent, surfactant, etc. as needed.

(High refractive index layer)
The refractive index of the high refractive index layer is preferably adjusted to a refractive index in the range of 1.4 to 2.2 by measuring at 23 ° C. and a wavelength of 550 nm. The thickness of the high refractive index layer is preferably 5 nm to 1 μm, more preferably 10 nm to 0.2 μm, and most preferably 30 nm to 0.1 μm. The means for adjusting the refractive index can be achieved by adding metal oxide fine particles and the like. The metal oxide fine particles used preferably have a refractive index of 1.80 to 2.60, more preferably 1.85 to 2.50.

  The kind of metal oxide fine particles is not particularly limited, and Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P and S A metal oxide having at least one element selected from can be used.

(Conductive layer)
In the hard coat film, a conductive layer may be formed on the hard coat layer. As the conductive layer provided, a generally well-known conductive material can be used. For example, metal oxides such as indium oxide, tin oxide, indium tin oxide, gold, silver, and palladium can be used. These can be formed as a thin film on the hard coat film by vacuum deposition, sputtering, ion plating, solution coating, or the like. Moreover, it is also possible to form a conductive layer using the organic conductive material which is the above-described π-conjugated conductive polymer.

  In particular, a conductive material that is excellent in transparency and conductivity, and that has a main component of any of indium oxide, tin oxide, and indium tin oxide, which can be obtained at a relatively low cost, can be suitably used. Although the thickness of the conductive layer varies depending on the material to be applied, it cannot be said unconditionally. However, the surface resistivity is 1000Ω or less, preferably 500Ω or less, and considering the economy, A range of 10 nm or more, preferably 20 nm or more and 80 nm or less, preferably 70 nm or less is suitable. In such a thin film, visible light interference fringes due to uneven thickness of the conductive layer are unlikely to occur.

<Polarizing plate>
A polarizing plate using the hard coat film of the present invention will be described. The polarizing plate can be produced by a general method.

  For example, the hard coat film of the present invention is subjected to alkali saponification treatment, and the treated hard coat film is attached to at least one surface of a polarizing film prepared by immersing and stretching in an iodine solution using a completely saponified polyvinyl alcohol aqueous solution. It is preferable to match.

  The other surface may be the hard coat film or the cellulose ester film described above. The film thickness of the cellulose ester film used for the other surface is preferably in the range of 5 to 34 μm from the viewpoint of adjusting smoothness and curl balance and further enhancing the effect of preventing winding deviation.

  In addition, commercially available products such as KC8UX, KC4UX, KC4UY, KC8UY, KC6UA, KC4UA, KC4UE, KC4CZ, KC8UCR, KC4FR (manufactured by Konica Minolta Advanced Layer Co., Ltd.), Arton Film (manufactured by JSR Corporation), Zeor Film Nippon Zeon Co., Ltd.) can be used.

  The polarizing film, which is the main component of the polarizing plate, is an element that transmits only light having a polarization plane in a certain direction. A typical polarizing film known at present is a polyvinyl alcohol polarizing film, which is a polyvinyl alcohol film. There are those in which iodine is dyed on a system film and those in which dichroic dye is dyed, but it is not limited to this.

  As the polarizing film, a polyvinyl alcohol aqueous solution is formed and dyed by uniaxial stretching or dyed, or uniaxially stretched after dyeing, and then preferably subjected to a durability treatment with a boron compound. The thickness of the polarizing film is in the range of 5 to 30 μm, preferably in the range of 8 to 15 μm.

  On the surface of the polarizing film, one side of the hard coat film according to the present invention is bonded to form a polarizing plate. It is preferably bonded with an aqueous adhesive mainly composed of completely saponified polyvinyl alcohol or the like.

(Adhesive layer)
The pressure-sensitive adhesive layer used on one side of the film to be bonded to the substrate of the liquid crystal cell is preferably optically transparent and exhibits moderate viscoelasticity and adhesive properties.

  Specific examples of the adhesive layer include adhesives or adhesives such as acrylic copolymers, epoxy resins, polyurethanes, silicone polymers, polyethers, butyral resins, polyamide resins, polyvinyl alcohol resins, and synthetic rubbers. A film such as a drying method, a chemical curing method, a thermal curing method, a thermal melting method, a photocuring method, or the like can be formed and cured using a polymer such as the above. Among them, the acrylic copolymer can be preferably used because it is most easy to control the physical properties of the adhesive and is excellent in transparency, weather resistance, durability and the like.

<Winding>
The air layer thickness held between the layers when the polarizing plate using the hard coat film of the present invention, the cellulose ester film according to the present invention or the hard coat film of the present invention is wound in a roll shape is 0.5 to in the range of 10 [mu] m, good Mashiku is in the range of 1 to 5 [mu] m. The air layer thickness (t ′) is a value obtained from an equation of t ′ = [{π (D ² −d ² ) / 4L} −t].

  In the above formula, D represents the winding diameter, d represents the winding core diameter, L represents the winding length, and t represents the thickness of the film.

  In addition, a method for winding a hard coat film, etc., provides a roller that the film touches in front of the winding shaft, and the film touches when winding the film or winding the film on the winding shaft. A method in which the film is wound while the roller is gradually separated at a constant distance (gap winding), a film winding part that winds the film around the core by rotating the core, and the film width on the core For example, an oscillating winding method in which winding is performed while periodically deviating in a certain range in a direction can be used.

  The thickness of the air layer can be controlled by adjusting the above-described winding conditions such as a tension condition during winding.

<Image display device>
The hard coat film of this invention is preferable at the point by which the performance excellent in visibility (clearness) is exhibited by using it for an image display apparatus. As an image display device, a reflection type, a transmission type, a transflective type liquid crystal display device, a liquid crystal display device of various driving methods such as a TN type, STN type, OCB type, VA type, IPS type, ECB type, and a touch panel display device And organic EL display devices and plasma displays. Among these image display devices, when the hard coat film of the present invention is used for a liquid crystal display device or a touch panel display device, it is preferable in terms of excellent visibility.

<Touch panel>
An example in the case of using the hard coat film of the present invention for a touch panel display device is shown in FIG.

  A conductive film 12 is formed on a hard coat film 11 (hereinafter referred to as double-sided hard coat film) 11 provided with a hard coat layer on both sides according to the present invention, and this is a glass substrate 13 on which a conductive film 15 is formed, By making the conductive layers face each other with a certain interval so that the conductive layers face each other, the resistive film type touch panel 10 can be configured. Electrodes (not shown) are arranged at the ends of the double-sided hard coat film 11 and the glass substrate 13 according to the present invention. The conductive film 12 comes into contact with the conductive film 15 on the glass substrate 13 by pressing the double-sided hard coat film 11 with a finger or a pen. The pressed position is detected by electrically detecting this contact through the electrode at the end. A dot-like spacer 14 is disposed on the conductive film 15 of the glass substrate 13 as necessary. Further, as shown in FIG. 2, the image display device 20 with an inner touch panel can be configured by mounting the touch panel 10 of FIG. 1 in the liquid crystal display panel.

  The hard coat film of the present invention is, for example, an inner touch panel as shown in FIG. 2 using a touch panel member under the upper surface side polarizing plate of a liquid crystal display device (upper surface side polarizing plate / liquid crystal cell / lower surface side polarizing plate configuration). It can also be used for a capacitive touch panel. In the capacitive touch panel, the conductive film 12 preferably has an electrode pattern such as a lattice shape arranged at a predetermined pitch. The electrode pattern of the conductive film is such that after the conductive film is formed, the conductive film is masked with the electrode pattern, the electrode pattern is formed by alkali etching, or laser irradiation is performed to continuously pattern the conductive film. Can be provided.

<Glass scattering prevention film for image display device>
Next, a glass scattering prevention film for an image display device using the hard coat film of the present invention will be described. FIG. 3 shows an example of a schematic cross-sectional view in which the glass scattering prevention film for an image display device using the hard coat film of the present invention is used in the image display device.

  The image display device 30 includes an image display panel 31, a conductive glass substrate 33 disposed on the display unit (display surface) of the image display panel 31 via an adhesive layer 32, and a conductive glass substrate 33. It is comprised roughly from the glass scattering prevention film 41 for image display apparatuses stuck.

  The conductive glass substrate 33 includes a glass substrate 34 and a conductive film 35. The glass scattering prevention film 41 for an image display device is adhered to the glass substrate 34 with an adhesive layer 43.

  The glass scattering prevention film 41 for an image display device comprising the hard coat film 42 of the present invention has high adhesiveness with an adhesive or the like, and does not require easy adhesion treatment. Moreover, sufficient scattering prevention property can be obtained for the glass scattering prevention film. In addition, deformation and the like hardly occur after the durability test, and the flatness (visibility) is excellent.

  The hard coat film 42 preferably has a refractive index in the range of 1.45 to 1.55 at a wavelength of 589 nm measured in accordance with JIS K7142-2008. The pressure-sensitive adhesive layer 43 also preferably has a refractive index of 1.40 to 1.55 at a wavelength of 589 nm measured in accordance with JIS K7142-2008, more preferably 1.45 to 1.52.

  The refractive index of the pressure-sensitive adhesive layer 43 can be adjusted by, for example, a method of increasing the refractive index by including an aromatic ring or a method of decreasing the refractive index by including a fluorine atom.

  By setting the refractive index of the pressure-sensitive adhesive layer 43 and the glass scattering prevention film 41 for an image display device within the above range, the refractive index when bonded to a glass substrate or the like is small, and the interference fringes are excellent.

  The thickness of the pressure-sensitive adhesive layer is preferably in the range of 5 to 30 μm, and more preferably in the range of 10 to 25 μm. As an adhesive which comprises an adhesive layer, an acrylic adhesive, a silicone adhesive, a urethane adhesive, a rubber adhesive, a polyester adhesive, etc. are mentioned. These pressure-sensitive adhesives may be emulsion type, solvent type, or solventless type. Among these pressure-sensitive adhesives, acrylic pressure-sensitive adhesives are preferable from the viewpoints of easy adhesion control and weather resistance. The acrylic pressure-sensitive adhesive is preferably a cross-linked acrylic resin having a weight average molecular weight in the range of 500 to 2,000,000, preferably in the range of 7,000 to 1,700,000. When the weight average molecular weight is in the above range, a film for preventing scattering can be obtained in which the adhesive force and the holding force are balanced. The aforementioned weight average molecular weight is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

  As the acrylic resin contained in the acrylic pressure-sensitive adhesive, a (meth) acrylic ester copolymer is used. As this (meth) acrylic acid ester copolymer, the (meth) acrylic acid ester having 1 to 20 carbon atoms in the alkyl group of the ester portion, a monomer having a functional group having active hydrogen, and, if desired, Copolymers with other monomers used are preferred. Examples of the (meth) acrylic acid ester having 1 to 20 carbon atoms in the alkyl group of the ester moiety include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, Examples include isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isooctyl (meth) acrylate. These may be used alone or in combination of two or more. Examples of the monomer having a functional group having active hydrogen include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth). (Meth) acrylic acid hydroxyalkyl esters such as acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, acrylamide, methacrylamide, N-methylacrylamide, N-methylmethacrylamide, N-methylol Acrylamides such as acrylamide and N-methylolmethacrylamide, monoalkylaminoalkyl (meth) acrylates such as methylaminoethyl (meth) acrylate and monoethylaminoethyl (meth) acrylate, Le acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, ethylenically unsaturated carboxylic acids such as citraconic acid. These may be used alone or in combination of two or more.

  In the acrylic pressure-sensitive adhesive, the (meth) acrylic acid ester copolymer used as a resin component may be any of random, block, and graft copolymers with respect to the copolymerization form. As the crosslinking agent used for the crosslinking treatment, a polyisocyanate compound or an epoxy compound is preferably used. A crosslinking agent may be used individually by 1 type, and may be used in combination of 2 or more type. Moreover, although the usage-amount is based also on the kind of crosslinking agent, it is the range of 0.01-20 mass parts normally with respect to 100 mass parts of said (meth) acrylic acid ester-type copolymer solid content, Preferably, 0.1 It is the range of -10 mass parts. A tackifier, antioxidant, ultraviolet absorber, light stabilizer, softener, silane coupling agent, filler and the like can be added to the acrylic pressure-sensitive adhesive. Furthermore, a protective film and a release sheet may be attached to the adhesive layer 43. Examples of the base material of the release sheet include polyethylene terephthalate, polyethylene, and polypropylene film. In order to make the surface of the release sheet substrate have release properties, a release agent such as a fluorine resin, a silicone resin, or a long-chain alkyl group-containing carbamate is attached to the surface by coating. The thickness of the release sheet substrate is preferably in the range of 5 to 300 μm, more preferably in the range of 10 to 200 μm.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
(Preparation of cellulose ester film 1)
-Preparation of silicon dioxide dispersion Aerosil R812
(Nippon Aerosil Co., Ltd., average diameter of primary particles: 7 nm) 10 parts by mass Ethanol 90 parts by mass The above was stirred and mixed with a dissolver for 30 minutes, and then dispersed with Manton Gorin. 88 parts by mass of methylene chloride was added to the silicon dioxide dispersion with stirring, and the mixture was stirred and mixed with a dissolver for 30 minutes to prepare a silicon dioxide dispersion dilution. It filtered with the fine particle dispersion | distribution dilution liquid filter (Advantech Toyo Co., Ltd .: Polypropylene wind cartridge filter TCW-PPS-1N).

<Preparation of Dope Composition 1>
(Cellulose ester resin)
Cellulose triacetate A (cellulose triacetate synthesized from linter cotton, acetyl group substitution degree 2.88, Mn = 14000) 90 parts by mass (additive)
Ester Represented by General Formula (X) (Exemplary Compound X-1) 5 parts by mass Ester Represented by General Formula (X) (Exemplary Compound X-12) 4 parts by mass (UV absorber)
TINUVIN 928 (manufactured by BASF Japan Ltd.) 3 parts by mass (fine particles)
Silicon dioxide dispersion dilution 4 parts by mass (solvent)
Methylene chloride 432 parts by mass Ethanol 38 parts by mass The above was put into a sealed container, heated and stirred, and dissolved completely. Azumi filter paper No. Azumi filter paper No. 24 was used to prepare a dope (dope composition 1).

  Next, the belt casting apparatus was used to uniformly cast on a stainless steel band support. With the stainless steel band support, the solvent was evaporated until the residual solvent amount reached 100%, and the stainless steel band support was peeled off. The cellulose ester film web was evaporated at 35 ° C., slit to 1.15 m width, and dried at a drying temperature of 140 ° C. while being stretched 1.15 times in the TD direction (film width direction) with a tenter. I let you. Then, it was dried for 15 minutes while being transported in a drying device at 120 ° C. with many rollers, slitted to a width of 1.3 m, knurled with a width of 10 mm and a height of 5 μm at both ends of the film, and wound on a core. The cellulose ester film 1 was obtained. The film thickness of the cellulose ester film 1 was 25 μm, and the winding length was 5000 m.

  In addition, the draw ratio of MD direction computed from the rotational speed of a stainless steel band support body and the driving speed of a tenter was 1.01 times.

(Production of cellulose ester films 2 to 5)
In producing the cellulose ester film 1, cellulose ester films 2 to 5 were produced in the same manner except that the film thickness was changed as described in Table 1.

[Preparation of Hard Coat Film 1]
On the surface A (the surface not in contact with the casting belt) of the cellulose ester film 1 produced as described above, a hard coat layer composition 1 described below was filtered with a polypropylene filter having a pore size of 0.4 μm, and an extrusion coater was used. After applying at a constant rate drying zone temperature of 50 ° C. and a reduced rate drying zone temperature of 50 ° C., the irradiation part is irradiated with an ultraviolet lamp while purging with nitrogen so that the oxygen concentration becomes 1.0% by volume or less. The coating layer is cured with an illuminance of 100 mW / cm ² and an irradiation amount of 0.2 J / cm ² to form a hard coat layer 1 having a dry film thickness of 2.5 μm, and the thickness of the air layer becomes 4 μm. In this manner, a roll-shaped hard coat film 1 was produced.

<< Hard Coat Layer Composition 1 >>
<Preparation of fluorine-siloxane graft compound>
The commercial name of the raw material used for the preparation of the fluorine-siloxane graft compound is shown.

Radical polymerizable fluororesin (A): Cefal coat CF-803 (hydroxy group number 60, number average molecular weight 15000; manufactured by Central Glass Co., Ltd.)
Single-end radical polymerizable polysiloxane (B): Silaplane FM-0721 (number average molecular weight 5000; manufactured by Chisso Corporation)
Radical polymerization initiator: Perbutyl O (t-butylperoxy-2-ethylhexanoate; manufactured by NOF Corporation)
Curing agent: Sumidur N3200 (biuret type prepolymer of hexamethylene diisocyanate; manufactured by Sumika Bayer Urethane Co., Ltd.)
(Synthesis of radical polymerizable fluororesin)
In a glass reactor equipped with a mechanical stirrer, thermometer, condenser and dry nitrogen gas inlet, cefal coat CF-803 (1554 parts by mass), xylene (233 parts by mass), and 2-isocyanatoethyl methacrylate (6 3 parts by mass) and heated to 80 ° C. in a dry nitrogen atmosphere. After reacting at 80 ° C. for 2 hours and confirming that the absorption of isocyanate disappeared by the infrared absorption spectrum of the sampled material, the reaction mixture was taken out to obtain 50% by mass of a radically polymerizable fluororesin via a urethane bond. .

(Preparation of fluorine-siloxane graft compound)
In a glass reactor equipped with a mechanical stirrer, thermometer, condenser and dry nitrogen gas inlet, the above synthesized radical polymerizable fluororesin (26.1 parts by mass), xylene (19.5 parts by mass), acetic acid n-butyl (16.3 parts by mass), methyl methacrylate (2.4 parts by mass), n-butyl methacrylate (1.8 parts by mass), lauryl methacrylate (1.8 parts by mass), 2-hydroxyethyl methacrylate (1 .8 parts by mass), FM-0721 (5.2 parts by mass), and perbutyl O (0.1 parts by mass) were heated to 90 ° C. in a nitrogen atmosphere, and held at 90 ° C. for 2 hours. Perbutyl O (0.1 part) was added, and the solution was further maintained at 90 ° C. for 5 hours to obtain a 35 mass% fluorine-siloxane graft compound solution having a weight average molecular weight of 171,000. The weight average molecular weight was determined by GPC. Moreover, the mass% of the fluorine-siloxane graft compound was calculated | required by HPLC (liquid chromatography).

(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass ( Photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
Fluorine-siloxane graft compound (35% by mass) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 2]
A hard coat film 2 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 2 described below.

<< Hard Coat Layer Composition 2 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass ( Photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
Optool DAC (fluorine compound, manufactured by Daikin Industries, Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 3]
A hard coat film 3 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 3 described below.

<< Hard Coat Layer Composition 3 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass Irgacure 184 (BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 4]
A hard coat film 4 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 4 described below.

<< Hard Coat Layer Composition 4 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass ( Photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
BYK-UV3510 (polyether-modified polydimethylsiloxane, manufactured by Big Chemie Japan Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 5]
A hard coat film 5 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 5 described below.

<< Hard Coat Layer Composition 5 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass ( Photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 6]
A hard coat film 6 was produced in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 6 described below.

<< Hard Coat Layer Composition 6 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 70 parts by mass Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin-Nakamura Chemical Co., Ltd.) 30 parts by mass ( Photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (UV absorber)
TINUVIN 928 (manufactured by BASF Japan Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 7]
In the production of the hard coat film 1, a roll-like hard coat film 7 was produced in the same manner except that irradiation with an ultraviolet lamp was performed without purging with nitrogen.

[Preparation of Hard Coat Film 8]
In the production of the hard coat film 2, a roll-like hard coat film 8 was produced in the same manner except that irradiation with a UV lamp was performed without purging with nitrogen.

[Preparation of hard coat films 9-12]
In the production of the hard coat film 7, roll-shaped hard coat films 9 to 12 were produced in the same manner except that the cellulose ester film 1 was changed to the cellulose ester films 2 to 5 shown in Table 1, respectively.

[Preparation of Hard Coat Film 13]
A hard coat film 13 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 7 described below.

<< Hard Coat Layer Composition 7 >>
(Actinic radiation curable resin)
Pentaerythritol tri / tetraacrylate (NK ester A-TMM-3L, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (NK Oligo UA-1100H, manufactured by Shin-Nakamura Chemical Co., Ltd.) 65 parts by mass (light Polymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 14]
A hard coat film 14 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 8 described below.

<< Hard Coat Layer Composition 8 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (NK Oligo UA-1100H, manufactured by Shin-Nakamura Chemical Co., Ltd.) 65 parts by mass (photopolymerization initiator) )
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 15]
A hard coat film 15 was produced in the same manner as in the production of the hard coat film 1 produced above except that the hard coat layer composition 9 was changed to the following.

<< Hard Coat Layer Composition 9 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (NK Oligo UA-15HA, manufactured by Shin-Nakamura Chemical Co., Ltd.) 65 parts by mass (photopolymerization initiator) )
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 16]
A hard coat film 16 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 10 described below.

<< Hard Coat Layer Composition 10 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (UA-306I, manufactured by Kyoeisha Chemical Co., Ltd.)
65 parts by mass (photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 17]
A hard coat film 17 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 11 described below.

<< Hard Coat Layer Composition 11 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (UA-306T, manufactured by Kyoeisha Chemical Co., Ltd.)
65 parts by mass (photopolymerization initiator)
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-354L
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 18]
A hard coat film 18 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 12 described below.

<< Hard Coat Layer Composition 12 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (NK Oligo UA-1100H, manufactured by Shin-Nakamura Chemical Co., Ltd.) 65 parts by mass (photopolymerization initiator) )
Irgacure 184 (manufactured by BASF Japan) 6 parts by mass (additive)
KF-351A
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of hard coat film 19]
A hard coat film 19 was prepared in the same manner except that the hard coat film composition 1 was changed to the hard coat layer composition 13 described below.

<< Hard Coat Layer Composition 13 >>
(Actinic radiation curable resin)
Dipentaerythritol pentaacrylate (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd.) 35 parts by mass Urethane acrylate (NK Oligo UA-1100H, manufactured by Shin-Nakamura Chemical Co., Ltd.) 65 parts by mass (photopolymerization initiator) )
Irgacure 184 (manufactured by BASF Japan) 3 parts by mass Irgacure 907 (manufactured by BASF Japan) 3 parts by mass (additive)
KF-351A
(Polyether-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by mass (solvent)
Propylene glycol monomethyl ether 20 parts by mass Methyl acetate 30 parts by mass Methyl ethyl ketone 70 parts by mass [Preparation of Polarizing Plate 101]
A polarizing plate 101 was prepared using a hard coat film 1 (described as HF1 in FIG. 4) and a cellulose ester film 1 (described as CE1 in FIG. 4).

(A) Production of Polarizing Film What was impregnated with 10 parts by mass of glycerin and 170 parts by mass of water in 100 parts by mass of polyvinyl alcohol (hereinafter abbreviated as PVA) having a saponification degree of 99.95 mol% and a polymerization degree of 2400 After melt-kneading and defoaming, it was melt extruded from a T die onto a metal roller to form a film. Then, it dried and heat-processed and obtained the PVA film.

  The obtained PVA film had an average thickness of 25 μm, a moisture content of 4.4%, and a film width of 3 m. Next, the obtained PVA film was continuously processed in the order of preliminary swelling, dyeing, uniaxial stretching by a wet method, fixing treatment, drying, and heat treatment to prepare a polarizing film. That is, the PVA film was preliminarily swollen in water at a temperature of 30 ° C. for 30 seconds, and immersed in an aqueous solution having an iodine concentration of 0.4 g / liter and a potassium iodide concentration of 40 g / liter at a temperature of 35 ° C. for 3 minutes. Subsequently, the film was uniaxially stretched 6 times in a 50% aqueous solution with a boric acid concentration of 4% under the condition that the tension applied to the film was 700 N / m, and the potassium iodide concentration was 40 g / liter and the boric acid concentration was 40 g / liter. Then, it was immersed in an aqueous solution having a zinc chloride concentration of 10 g / liter and a temperature of 30 ° C. for 5 minutes for fixing. Thereafter, the PVA film was taken out, dried with hot air at a temperature of 40 ° C., and further heat-treated at a temperature of 100 ° C. for 5 minutes. The obtained polarizing film had an average thickness of 13 μm, a polarizing performance of a transmittance of 43.0%, a polarization degree of 99.5%, and a dichroic ratio of 40.1.

(B) Production of Polarizing Plate A polarizing plate 101 was produced by bonding the polarizing film, the cellulose ester film 1 and the hard coat film 1 in accordance with the following steps 1 to 4.

  Process 1: The above-mentioned polarizing film was immersed in the storage tank of the polyvinyl alcohol adhesive agent solution of 2 mass% of solid content for 1-2 seconds.

  Step 2: The cellulose ester film 1 and the hard coat film 1 were subjected to alkali treatment under the following conditions. Next, in Step 1, a polarizing film (described as PV1 in FIG. 4) was immersed in the polyvinyl alcohol adhesive solution. The excess adhesive adhered to the immersed polarizing film is lightly removed, and the cellulose ester film film 1 and the hard coat film 1 are sandwiched between the polarizing films as shown in FIG. Was wound so that the thickness became 5 μm, and a roll-shaped polarizing plate 101 was produced.

(Alkali treatment)
Saponification step 2.5 mol / L-KOH 50 ° C. 120 seconds Water washing step Water 30 ° C. 60 seconds Neutralization step 10 mass% HCl aqueous solution 30 ° C. 45 seconds Water washing step Water 30 ° C. 60 seconds After saponification treatment, water washing, neutralization, water washing Perform in order and then dry at 100 ° C.

Process 3: The laminate was bonded at a speed of about 2 m / min at a pressure of ^{20 to} 30 N / cm ² with two rotating rollers. At this time, care was taken to prevent bubbles from entering.

  Step 4: The sample produced in Step 3 was dried in a dryer at a temperature of 100 ° C. for 5 minutes to produce a roll-shaped polarizing plate.

<Production of Polarizing Plates 102 to 119>
In the production of the polarizing plate 101, roll-shaped polarizing plates 102 to 119 were produced in the same manner except that the hard coat film 1 was changed to the hard coat films 2 to 19, respectively. None of the roll-shaped polarizing plates had any winding deviation.

<Production of Liquid Crystal Display Device 201>
(Durability test evaluation)
The produced roll-shaped polarizing plate 101 was wrapped in an aluminum moisture-proof sheet and stored for 25 days in a thermostatic bath at 50 ° C. and 80% relative humidity assuming long-term transportation. After storage for 25 days, an adhesive layer (referred to as NS1 in FIG. 4) was provided as follows, and then incorporated into a liquid crystal display device to produce a liquid crystal display device 201.

(Adhesive layer)
A commercially available acrylic adhesive is applied to the cellulose ester film 1 of the polarizing plate so that the thickness after drying is 25 μm, dried in an oven at 110 ° C. for 5 minutes to form an adhesive layer, and then peelable to the adhesive layer. A protective film was attached.

(Liquid crystal display device 201)
Of two pairs of polarizing plates installed with a liquid crystal layer sandwiched between 21.5 inch liquid crystal display devices (IPS226V-PN, LG Electronics Japan Co., Ltd.), the polarizing plate on one side on the viewer side is peeled off, The pressure-sensitive adhesive layer and the liquid crystal cell glass were bonded so that the produced polarizing plate 101 had the hard coat layer on the viewing side. The liquid crystal display device 201 was manufactured by arranging the transmission axis of the polarizing plate on the viewer side and the transmission axis of the polarizing plate on the backlight side to be orthogonal to each other.

<Production of Liquid Crystal Display Devices 202 to 219>
In the production of the liquid crystal display device 201, except that the polarizing plate 101 was changed to the polarizing plates 102 to 119, respectively, after the endurance test of the polarizing plate, it was incorporated into the liquid crystal display device to produce the liquid crystal display devices 202 to 219. .

<Evaluation>
The following contents were evaluated about the produced hard coat film, polarizing plate, and liquid crystal display device.

1. Difference in contact angle between water and hard coat film before and after alkali treatment (θ _Δ )
From the water contact angle (θ) of each hard coat layer before the alkali treatment of the hard coat films 1 to 19, the water contact angle (θa) of each hard coat layer after the alkali treatment at the time of preparing the polarizing plate is subtracted, The difference (θ _Δ ) in water contact angle before and after alkali treatment was used.

  Here, the contact angle with water is measured by a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.) in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55% after leaving the sample for 24 hours in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%. The contact angle of pure water was measured 1 minute after dropping 1 μL of pure water using a product name DropMaster DM100). In addition, the measurement was performed seven times, and the average value of the five measurement values excluding the maximum value and the minimum value of the measurement values was defined as the contact angle of the sample.

2. Polarizing plate / winding deviation evaluation The above-prepared roll-shaped polarizing plates 101 to 119 are placed on a gantry, and a vibration test is performed for 1 hour in accordance with JIS Z0232 using a general-purpose vibration test apparatus J series (manufactured by IMV Corporation). The difference between the winding misalignment position after the vibration test and the non-winding misalignment position was measured with a curved scale and evaluated according to the following criteria.

A: 0 mm (no winding deviation)
○: Less than 5 mm Δ: 5 mm or more, 10 mm or less ×: More than 10 mm (practical problem)
3. Liquid crystal display device Visibility was evaluated by evaluating unevenness and flatness of the liquid crystal display devices 201 to 219.
a. Unevenness Evaluation Each of the liquid crystal display devices produced above was observed from the front with a black display, and unevenness was evaluated according to the following criteria.

A: Unevenness due to deformation is not observed at all. ○: Unevenness due to deformation is slightly observed. Δ: Unevenness due to fine deformation is observed. X: Unevenness due to deformation is observed.
b. Flatness Evaluation Each liquid crystal display device manufactured above is placed on a desk 80 cm high from the floor, and a daylight direct fluorescent lamp (FLR40S • D / MX Panasonic is placed on the ceiling 3 m high from the floor. 10 sets of 40W × 2 pieces were arranged as a set at intervals of 1.5 m. In this case, when the evaluator is in front of the display surface of the liquid crystal display panel, the fluorescent lamp is arranged so that the fluorescent lamp comes to the back from above the evaluator's head, and the flatness is evaluated according to the following criteria.

◎: Fluorescent lamp looks straight ○: Fluorescent lamp appears to be bent slightly △: Fluorescent lamp appears to be bent ×: Fluorescent lamp appears to be greatly bent Table 1 shows the above evaluation results.

As can be seen from the results in Table 1, the difference (θ _Δ ) in water contact angle before and after the alkali treatment of the hard coat layer is in the range of 5 to 55 °, and the film thickness of the cellulose ester film is 5 to 5 It can be seen that the use of a hard coat film within the range of 34 μm exhibits an excellent effect on winding deviation. Moreover, it turns out that the polarizing plate comprised from the hard coat film of this invention exhibits the effect excellent in the nonuniformity after a durability test, and planarity. Thereby, it turns out that the liquid crystal display device incorporating the polarizing plate comprised from the hard coat film of this invention is excellent in visibility.

  About the hard coat films 1-19 before an alkali treatment, the hardness was confirmed by the pencil hardness test. Using the test pencil specified by JIS-S6006, according to the pencil hardness evaluation method specified by JIS-K5400, the hard coat layer surfaces of the hard coat films 1 to 19 are repeated 5 times with a pencil of each hardness using a weight of 500 g. As a result of measuring the hardness of scratches and scratches, the pencil hardness of the hard coat film of the present invention was all H or higher.

Example 2
In the production of the hard coat film 3 of Example 1, hard coat films 20 to 24 were produced in the same manner except that the decreasing rate drying zone temperature of the hard coat layer was changed as described in Table 2. Furthermore, it carried out similarly to the polarizing plate 103 of Example 1, and produced the roll-shaped polarizing plates 120-124 using the hard coat films 20-24, respectively. In all cases, there was no winding deviation.

Subsequently, the water contact angle before the alkali treatment of the prepared hard coat films 20 to 24 and the water contact angle after the alkali treatment after the production of the polarizing plate were measured, and the difference between the water contact angles before and after the alkali treatment was measured. (Θ _Δ ) was determined.

  Further, the winding deviation of the polarizing plate 103 and the polarizing plates 120 to 124 was evaluated in the same manner except that the vibration test time for evaluating the winding deviation in Example 1 was changed to 3 hours. Furthermore, about each hard-coat layer of the hard-coat film 3 and 20-24, it measures 10 times using the optical interference type surface roughness meter (the ZYGO company make, NewView5030), From the average of a measurement result, each hard-coat layer of Arithmetic mean roughness Ra was determined.

  Moreover, the durability test of the polarizing plate 103 and the polarizing plates 120 to 124 after the durability test was performed in the same manner as in Example 1 except that the durability test was changed to 65 ° C. and a relative humidity of 80%. 103 and polarizing plates 120 to 124 were provided with an adhesive layer as described in FIG. 4 and incorporated in a liquid crystal display device to evaluate the visibility. The obtained results are shown in Table 2.

  As can be seen from the results of Table 2, by using the hard coat film of the present invention in which the arithmetic average roughness Ra of the hard coat layer is controlled to 2 to 100 nm, excellent winding displacement resistance can be obtained in a more severe vibration test. Therefore, it turns out that it is preferable. Moreover, it turns out that the effect excellent in the nonuniformity and flatness after a more severe durability test is exhibited by using the polarizing plate comprised from the hard coat film of this invention which controlled Ra to 2-100 nm. More preferably, the arithmetic average roughness Ra of the hard coat layer is in the range of 5 to 80 nm.

Example 3
In the production of the hard coat film 3 of Example 1, hard coat films 25 and 26 were produced in the same manner except that the active ray curable resin of the hard coat layer composition was changed as described in Table 3. Further, in the same manner as the polarizing plate 103 of Example 1, polarizing plates 125 and 126 were produced using the hard coat films 25 and 26. In all cases, there was no winding deviation.

The water contact angle before the alkali treatment of these produced hard coat films 25 and 26 and the water contact angle after the alkali treatment of the polarizing plate production were measured, and the difference between the water contact angles before and after the alkali treatment (θ _Δ ) Further, the winding deviation of the polarizing plate 103 and the polarizing plates 125 and 126 was evaluated in the same manner except that the vibration test time for evaluation of the winding deviation in Example 1 was changed to 2 hours.

  An adhesive layer is provided on the polarizing plate 103 and the polarizing plates 125 and 126 after the endurance test in the same manner as in Example 1 except that the durability test condition assuming long-term transportation is changed to 65 ° C. and a relative humidity of 80%. The visibility was incorporated into the display device. The obtained results are shown in Table 3.

  Pentaerythritol tri / tetraacrylate is PETA, trimethylolpropane triacrylate is TMPTA, tris (2-acryloyloxyethyl) isocyanurate (NK ester A-9300, manufactured by Shin-Nakamura Chemical Co., Ltd.) is ICTA, isocyanuric acid Table 3 shows ethoxy-modified diacrylate (Aronix M-215, manufactured by Toagosei Co., Ltd.).

  As can be seen from the results in Table 3, the hard coat film of the present invention using an active energy ray-curable isocyanurate derivative for the hard coat layer is preferable because excellent winding displacement resistance is obtained in a more severe vibration test. I understand that. In addition, by using a polarizing plate composed of the hard coat film of the present invention using an active energy ray-curable isocyanurate derivative, it exhibits excellent effects in unevenness and flatness after a more severe durability test. I understand.

Example 4
In the preparation of the dope composition 1 of the cellulose ester film 1 of Example 1, the dope composition was similarly changed except that 8 parts by mass of the acrylic polymer synthesized below was added instead of 4 parts by mass of the additive X-12. Product 2 was prepared. Subsequently, in producing the cellulose ester film 1, cellulose ester films 6 to 9 were similarly produced except that the stretching conditions in the TD direction by the tenter were changed as described in Table 4. In all cases, there was no winding deviation.

(Synthesis of acrylic polymer)
Methyl acrylate 10 parts by weight 2-hydroxyethyl acrylate 1 part by weight Azobisisobutyronitrile (AIBN) 1 part by weight Toluene 30 parts by weight Four-necked flask (input, thermometer, reflux condenser, nitrogen introduction) And the temperature is gradually raised to 80 ° C., and the polymerization is carried out for 5 hours while stirring. After the polymerization is completed, the polymer solution is poured into a large amount of methanol to precipitate, and further washed with methanol. The polymer was purified and dried to obtain an acrylic polymer having a weight average molecular weight of 5,000 (measured by GPC).

  Next, double-sided hard coat films 26 to 29 were prepared in the same manner as the hard coat film 3 except that the hard coat layer composition 3 of Example 1 was provided on both sides of the produced cellulose ester films 6 to 9. did. Furthermore, in the hard coat film 3, the hard coat layer composition 3 was provided on both surfaces, and the double-sided hard coat film 30 was produced.

About these produced double-sided hard coat films 26-30, the alkali treatment was implemented on the same conditions as the alkali treatment in the polarizing plate preparation of Example 1, and the difference ((theta) ( _DELTA )) of the water contact angle before and behind an alkali treatment was measured.

  Moreover, it carried out similarly to the vibration test of the polarizing plate of Example 1, and performed the vibration test of the double-sided hard coat films 26-30, and evaluated winding shift | offset | difference.

  Next, the in-plane retardation value Ro and the thickness direction retardation value Rth of the cellulose ester film 1 and 6 to 9 were measured by the following methods.

Using an automatic birefringence meter KOBRA-21ADH (manufactured by Oji Scientific Instruments), a three-dimensional refractive index measurement is performed at an optical wavelength of 590 nm under an environment of a temperature of 23 ° C. and a relative humidity of 55%, and the vertical and horizontal each direction of the refractive indices _n x _thickness, n y, seek _{n z,} were determined Ro and Rth of the cellulose ester film by the following equation.

_{Ro = (n x -n y)} × d
Rth = ((n _x + _ny ) / 2−n _z ) × d.
(Wherein, n _x is a refractive index in a slow axis direction in the substrate film surface, n _y is the refractive index in the direction perpendicular to the slow axis in the base film surface, the thickness of the n _z is a substrate film (The refractive index in the direction, d represents the thickness (nm) of the base film)
The results obtained are shown in Table 4.

(Preparation of conductive hard coat films 1 to 5)
Next, about the double-sided hard coat films 26-30, the electroconductive film was formed with the following method and the electroconductive hard coat films 1-5 were produced.

  Conductive hard coat films 1 to 5 were produced by providing a conductive film of indium tin oxide (ITO) having a surface resistivity of about 400Ω on both sides of the double-sided hard coat films 26 to 30 by a sputtering method.

  Next, an inner touch panel was produced using each of the two produced conductive hard coat films 1 to 5 (FIG. 2). A dot spacer was formed in advance on the conductive film (21D) of one of the two conductive hard coat films, and then the two conductive films were opposed to produce an inner touch panel. The obtained touch panel is assembled under the upper surface side polarizing plate (21F1) of the liquid crystal display device having the configuration of the upper surface side polarizing plate (21F1) / liquid crystal cell / lower surface side polarizing plate (21F2), and an inner touch panel is manufactured. The black display screen was observed by changing the front direction and the visual field direction, and the visibility (color change) was evaluated according to the following criteria. The results obtained are shown in Table 4.

<Evaluation>
Visibility (color change) evaluation ○: No color change of touch panel Δ: Color change of touch panel is observed to some extent ×: Color change of touch panel is large. Practical problem level

  As can be seen from the results in Table 4, using a conductive hard coat film composed of the double-sided hard coat film according to the present invention for a touch panel is preferable because excellent visibility (inhibition of color change) can be obtained. I understand. Among them, the conductive hard coat composed of the double-sided hard coat film according to the present invention using the cellulose ester film in which the in-plane retardation Ro is adjusted to 0 to 5 nm and the retardation in the thickness direction is adjusted to the range of -10 to 10 nm. It can be seen that using a film for a touch panel is particularly preferable because excellent visibility (inhibition of color change) is obtained. Moreover, the double-sided hard coat film of the present invention has excellent resistance to winding deviation.

Example 5
In the production of the hard coat film 3 of Example 1, the hard coat film 31 was produced in the same manner except that the cellulose ester film 1 was changed to the cellulose ester film 6. In addition, in the production of the polarizing plate of Example 1 using the hard coat film 31, a roll-shaped polarization was similarly performed except that the cellulose ester film 1 to be bonded to the surface opposite to the hard coat film was changed to the cellulose ester film 6. A plate 127 was produced. Further, using the hard coat film 25, a roll-shaped polarizing plate 128 was produced in the same manner as in Example 1. In all cases, there was no winding deviation.

The water contact angle before the alkali treatment of the prepared hard coat film 31 and the water contact angle after the alkali treatment after the production of the polarizing plate were measured, and the difference in the water contact angle before and after the alkali treatment (θ _Δ ). Asked.

  In addition, the winding deviation of the polarizing plate 103, the polarizing plate 127, and the polarizing plate 128 was evaluated in the same manner as in Example 1. Further, in the same manner as in Example 1, an adhesive layer as shown in FIG. 4 is provided on the polarizing plate 103, the polarizing plate 127, and the polarizing plate 128 after the durability test, and the liquid crystal display device 227 and the liquid crystal are incorporated into the liquid crystal display device. A display device 228 was produced and evaluated in the same manner as in Example 1. Furthermore, the color change of the visibility evaluation was evaluated according to the following criteria. The obtained results are shown in Table 5.

<Evaluation>
-Color change The liquid crystal display device was viewed on a black display screen while changing the front direction and the viewing direction, and the visibility was evaluated according to the following criteria.

○: No change in color of liquid crystal display device Δ: Some change in color of liquid crystal display device is observed ×: Large change in color of liquid crystal display device

  As can be seen from the results in Table 5, a book using a cellulose ester film in which an acrylic polymer was added and the in-plane retardation Ro was adjusted to 0 to 5 nm and the retardation in the thickness direction was adjusted to a range of -10 to 10 nm. It can be seen that the hard coat film according to the invention is excellent because it has excellent resistance to winding misalignment and is particularly excellent in visibility when used in a liquid crystal display device.

Example 6
(Production of substrate-less adhesive sheet)
On the release surface of the release sheet (trade name: SP-PET 381031, thickness 38 μm, manufactured by Lintec Corporation), using a die coater, the pressure-sensitive adhesive-containing composition 1 was applied so that the thickness after drying was 15 μm. It dried at 120 degreeC for 2 minute (s), the adhesive layer was formed, and the base material-less adhesive sheet which consists of a peeling sheet and the adhesive layer formed in the peeling surface was obtained.

<< Adhesive-containing composition 1 >>
The following composition was stirred to prepare an adhesive-containing composition 1.
-79% by mass of n-butyl acrylate, 20% by mass of methyl acrylate,
Acrylate ester copolymer obtained by copolymerizing 1% by mass of 2-hydroxyethyl acrylate (molecular weight 800,000, concentration 35% by mass) 100 parts by mass. Toluene and xylylene diisocyanate trifunctional adduct (trade name) : TD-75, concentration 75% by mass, manufactured by Soken Chemical Co., Ltd.) 0.1 part by mass [Preparation of glass scattering prevention film for image display device and image display device]
The roll-shaped hard coat films 1 to 19 produced in Example 1 were wrapped in an aluminum moisture-proof sheet, stored for 25 days in a thermostatic bath at a temperature of 50 ° C. and a relative humidity of 80% assuming long-term transportation, and a durability test was performed. . After the durability test, the adhesive layer of the substrate-less pressure-sensitive adhesive sheet was bonded to both surfaces of the hard coat films 1 to 19 to obtain glass scattering prevention films 1 to 19 for an image display device.

  Next, after bonding the glass plate having a thickness of 1 mm and the side opposite to the surface on which the hard coat layer is provided, the adhesive layer of the base material-less pressure-sensitive adhesive sheet of each hard coat layer is attached to a liquid crystal display device with a touch panel ( Image display devices 1 to 19 were prepared by bonding to a model name: LCD-USB10XB-T (manufactured by I / O Data Equipment Co., Ltd.), and the visibility was evaluated according to the following criteria.

<Evaluation>
・ Visibility evaluation In the room where 10 sets are arranged at 1.5m intervals with 2 sets of 40W x 2 daylight straight tube fluorescent lamps (FLR40S, D / MX manufactured by Panasonic Corporation) on the ceiling. The display device was observed from various angles in a black display state, and the state of reflected light reflected on the image display device was evaluated according to the following criteria.

Evaluation criteria ○: Level at which no interference fringes of reflected light reflected on the image display device can be seen at all ×: Level at which interference fringes of reflected light reflected on the image display device are slightly visible, which is a problem in practice XX: Image display device The level at which interference fringes of reflected light reflected in the can be clearly seen.

-Evaluation of anti-scattering properties of glass anti-scattering film for image display device Substrate only on the non-coated surface (surface opposite to the surface on which the hard-coating layer is provided) of hard-coated films 1 to 19 after the durability test The glass scattering prevention films 1-19 for image display apparatuses which bonded the adhesive layer of the less adhesive sheet were bonded together with the glass plate of thickness 1mm.

  Then, the laminated body which consists of a glass plate and a scattering prevention film was arrange | positioned so that a scattering prevention film might face upwards on a stand with a height of 10 mm.

  Next, an iron ball was dropped from a height of 30 cm onto the anti-scattering film of the laminate, and the glass scattering state was visually observed and evaluated according to the following criteria.

<Evaluation>
・ Glass scattering prevention evaluation criteria ○: The scattering prevention film was not torn Δ: The scattering prevention film was slightly torn ×: The scattering prevention film was torn

  As can be seen from the results in Table 6, the glass scattering prevention film for an image display device composed of the hard coat film of the present invention has excellent visibility when used in an image display device, and also has excellent glass scattering prevention properties. I understand that.

  The hard coat film of the present invention suppresses slipperiness between films, provides an effect of preventing winding deviation, suppresses buckling deformation and distortion of the film when wound in a roll shape, and improves flatness and unevenness. It is an excellent hard coat film. The hard coat film is suitable for a glass scattering prevention film for an image display device having good visibility, a touch panel, a polarizing plate and a liquid crystal display device.

DESCRIPTION OF SYMBOLS 10 Touch panel 11 Double-sided hard coat film 12 Conductive film 13 Glass substrate 14 Spacer 15 Conductive film 20 Image display device 21A with inner touch panel Hard coat layer 21B Hard coat layer 21C Cellulose ester film 21D Conductive film (ITO layer)
21E Liquid crystal cell 21F1 Upper surface side polarizing plate 21F2 Lower surface side polarizing plate 21G Reflector DS Dot / spacer 30 Image display device 31 Image display panel 32 Adhesive layer 33 Conductive glass substrate 34 Glass substrate 35 Conductive film 41 Glass for image display device Anti-scattering film 42 Hard coat film 43 Adhesive layer CE1 Cellulose ester film HC1 Hard coat layer KF1 Hard coat film PV1 Polarizing film NS1 Adhesive layer

Claims (5)

A method for producing a hard coat film, comprising producing a hard coat film having a hard coat layer on at least one surface of a cellulose ester film having a thickness in the range of 5 to 34 μm, and winding the roll into a roll. When the layer is alkali-treated under the conditions shown below, the water contact angle (θ) before the alkali treatment is in the range of 50 to 120 °, and the difference between the water contact angles before and after the alkali treatment (θ _Δ ) is adjusted to be within a range of 5 to 55 ° ,
The method for producing a hard coat film , wherein the thickness of the air layer held between the layers when winding in the roll shape is within a range of 0.5 to 10 μm .
Here, the difference (θ _Δ ) between the water contact angle before and after the alkali treatment was alkali-treated under the conditions shown below from the water contact angle (θ) of the hard coat layer before the alkali treatment of the hard coat film. This is a value obtained by subtracting the water contact angle (θa) of the subsequent hard coat layer to obtain the difference (θΔ) in water contact angle before and after the alkali treatment.
The alkali treatment condition is a condition in which the hard coat film is immersed in a 2.5 mol / L potassium hydroxide solution at a temperature of 50 ° C. for 120 seconds.
The contact angle with water is that the sample is left for 24 hours in an atmosphere at a temperature of 23 ° C. and a relative humidity of 55%, and then 1 μL of pure water is dropped using a contact angle meter in an atmosphere of a temperature of 23 ° C. and a relative humidity of 55%. The contact angle of pure water after 1 minute is measured. In addition, it is the value which measured 7 times and averaged five measured values except the maximum value and minimum value of the measured value. 2. The method for producing a hard coat film according to claim 1, wherein an arithmetic average roughness Ra (JIS B0601: 2001) of the hard coat layer is adjusted to be in a range of 2 to 100 nm . The method for producing a hard coat film according to claim 1 , wherein the hard coat layer contains an active energy ray-curable isocyanurate derivative . When the retardation value of the cellulose ester film was measured at an optical wavelength of 590 nm under an environment of a temperature of 23 ° C. and a relative humidity of 55%, the in-plane retardation value Ro was in the range of 0 to 10 nm, and the thickness direction The method for producing a hard coat film according to any one of claims 1 to 3, wherein the retardation value Rth is adjusted so as to fall within a range of -10 to 10 nm . Polarization using a hard coat film produced by the method for producing a hard coat film according to any one of claims 1 to 4 and a cellulose ester film having a thickness in the range of 5 to 34 µm. Sandwich the element, and
The manufacturing method of the polarizing plate characterized by making the thickness of the air layer hold | maintained between layers when winding in roll shape in the range of 0.5-10 micrometers .

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