KR20180104012A - A polyester film and a method for producing the same, a hard coat film and a manufacturing method thereof, - Google Patents

Abstract

A polyester film having a thickness of 40 to 500 占 퐉 and having an average vertical stress A in the slow axis direction in the surface layer of 1 占 퐉 and an average vertical stress B in the direction orthogonal to the slow axis direction in the film plane of 30 to 100 MPa .

Description

A polyester film and a method for producing the same, a hard coat film and a manufacturing method thereof,

The present disclosure relates to a polyester film, a method of manufacturing the same, a hard-coated film, a method of manufacturing the same, an image display device, and a touch panel.

In applications where chemically tempered glass has been used, the substitution of glass as a hard coat film in which a hard coat layer is laminated on a substrate film has been attracting attention as the hardening technique of the hard coat material progresses. An example of the hard coat film is a protective film on the outermost surface of an image display apparatus such as a touch panel.

For example, Patent Document 1 discloses "a laminated base material in which a functional layer is formed on one side to form a laminate, a light-transmissive base material having birefringence in a plane,

And a refractive index adjusting layer which is laminated on the light transmitting substrate and has a birefringence in the plane, the refractive index adjusting layer being located between the light transmitting substrate and the functional layer,

The refractive index n _{1x in the} direction of the slow axis which is the direction with the greatest refractive index in the plane of the light-transmitting substrate, the refractive index n _2x of the refractive index adjusting layer in the direction parallel to the slow axis direction of the light- And the refractive index n _3x of the functional layer in the direction parallel to the slow axis direction of the light-transmitting substrate,

n _1x <n _2x <n _3x , or n _1x > n _2x > n _3x

, &Lt; / RTI &gt;

A refractive index n _{1y in the} direction of the fast axis perpendicular to the slow axis direction of the light transmitting substrate, a refractive index n _2y of the refractive index adjusting layer in the direction parallel to the fast axis direction of the light transmitting substrate, The refractive index _n3y of the functional layer in the direction parallel to the fast axis direction of the substrate is _smaller than the refractive index _n3y of the functional layer,

n _1y <n _2y <n _3y , or n _1y > n _2y > n _3y

Quot; laminated substrate "is satisfied.

Patent Document 2 discloses that "a coating layer is formed on both surfaces of a multilayer polyester film having a laminated structure of at least three or more layers and the polyester layer of the substrate surface layer has a higher softening point than the middle layer, and an adhesive layer , Wherein the coating layer is formed of a coating liquid containing a crosslinking agent in an amount of 70% by weight or more based on the nonvolatile component.

Patent Document 3 discloses a monoaxially oriented polyester film having the following characteristics:

(1) the surface of the film has scratches of 1 μm or more in height difference of 1 or less per 1 m ² , and scratches of 0.3 μm or more and less than 1 μm in height difference of 20 or less per 1 m ² ,

(2) the number of foreign matter having a diameter of not less than 100 mu m per 1 m &lt; ² &gt;

(3) the three-dimensional average surface roughness (SRa) of the film surface is in the range of 0.020 to 0.060 mu m, and

(4) The maximum distortion of the main axis of alignment of the film measured by a microwave transmission type molecular alignment meter is within 7 degrees. "

Patent Document 4 discloses a uniaxially oriented coextruded laminated film comprising a polyester layer of at least three layers of an A layer, a B layer, and a C layer, wherein the outermost layer A and the layer C have an average particle diameter of 0.1 to 5.0 μm Wherein the B layer as the intermediate layer is composed of a dicarboxylic acid component, an aliphatic or alicyclic diol component, and a polyalkyl having a number average molecular weight of 300 to 4000 And a ratio of the thickness occupied by the total film thickness of the B layer to the total film thickness of the polyester is 65 to 95% Quot; uniaxially oriented laminated polyester film "

Patent Document 5 discloses that "a polyester film satisfying the following formula:

0m? C _S <0.003L ² / 8W

0m? C _CT < 0.003L ² / 4W

0.8m? W? 6.0m

20m? L? 30m

Where C _S [unit: m] represents the value of the full width arc of the film, C _CT [unit: m] represents the value of the half circular arc of the center position in the film width direction, W [unit: m ] Represents the film width, and L [unit: m] represents the film length at the time of measuring the full-width arc and the semi-circular arc ".

Patent Document 1: JP-A-2013-257550 Patent Document 2: JP-A-2015-128897 Patent Document 3: JP-A-2005-2220 Patent Document 4: JP-A-2004-351788 Patent Document 5: International Publication No. 2015/46122

In the films disclosed in Patent Documents 1 to 5, the vertical stress at the front surface is insufficient, and when the load is locally applied in the thickness direction of the film, the concave portion is apt to occur. It is considered that cracking or peeling of the hard coat layer tends to occur when a hard coat film obtained by laminating a hard coat layer on these films is produced and subjected to punching processing.

The present disclosure aims to provide a polyester film in which a concave portion is less likely to be generated even when a load is locally applied in the thickness direction of the film, and a method for producing the same.

It is another object of the present invention to provide a hard coat film which hardly causes cracking and peeling of a hard coat layer when a hard coat film obtained by laminating a hard coat layer on a polyester film is produced and punched, .

It is another object of the present disclosure to provide an image display apparatus and a touch panel in which deterioration of visibility due to irregularity in irregularity is suppressed even if a locally applied load is applied to a display screen.

In order to achieve the above object, the following means are provided.

&Lt; 1 > The steel sheet according to any one of &lt; 1 &gt; to &lt; 1 &gt;, wherein the thickness is 40 to 500 [mu] m, the vertical stress A in the longitudinal direction of the surface layer at 1 mu m and the average vertical stress B in the direction orthogonal to the longitudinal axis direction, Ester film.

&Lt; 2 > A polyester film according to < 1 >, which is a substrate film of a hard coat film.

<3> The polyester film according to <1> or <2>, which is a uniaxially oriented polyester film.

&Lt; 4 > The polyester film according to any one of < 1 > to < 3 >, wherein the retardation Re in the film plane at a measurement wavelength of 589 nm is 4000 to 50000 nm.

&Lt; 5 > The polyester film according to < 1 > to < 4 >, wherein the average value of the shear yield stress in the slow axis direction in the surface layer of 1 μm and the shear yield stress in the direction perpendicular to the slow axis direction in the film plane is 20 to 60 MPa &Lt; / RTI &gt;

<6> The polyester film according to any one of <1> to <5>, wherein the ratio of the normal shear stress to the shear vertical stress B is 1.1 to 2.0.

<7> The polyester film according to any one of <1> to <6>, wherein the ratio of the retardation Re in the film plane to the retardation Rth in the film thickness direction at a measurement wavelength of 589 nm of the polyester film is 0.6 to 1.2.

&Lt; 8 > A hard coat film having a base film comprising the polyester film according to any one of < 1 > to < 7 >, and a hard coat layer laminated on at least one surface of the base film.

<9> The hard coat film according to <8>, wherein the hard coat layer has a thickness of 5 μm or more.

&Lt; 10 >

At least the structure derived from a), the structure derived from b), the structure derived from c) and d)

The hard coat layer contains 15 to 70 mass% of the structure derived from the following a), 25 to 80 mass% of the structure derived from the following b), and 0.1 to 0.1 mass% of the following composition (c) in the case where the total solid content of the hard coat layer is 100 mass% To 10% by mass, and d) from 0.1% by mass to 10% by mass, based on the total mass of the hard coat film.

a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and having a molecular weight of 300 or less

b) a compound having a group containing three or more ethylenically unsaturated double bonds in the molecule

c) a radical polymerization initiator

d) cationic polymerization initiator

<11> An image display device comprising an image display element and a hard coat film described in any one of <8> to <10>, wherein the hard coat film is disposed on the outermost surface.

<12> A touch panel comprising the hard coat film according to any one of <8> to <10>, wherein the hard coat film is disposed on the outermost surface.

<13> A transverse stretching apparatus having a plurality of clips running along a pair of rails provided on both sides of a film conveying path,

A preheating step of preheating an unoriented or vertically stretched polyester film at a heating rate of 600 DEG C / min or less,

Transversely stretching was performed in such a manner that both ends of the preheated polyester film were gripped by a plurality of clips and stretched in a direction orthogonal to the film transport path to gradually increase the surface temperature of the polyester film from the start of transverse stretching to the end of transverse stretching , The surface temperature at the start of transverse stretching is controlled to be not lower than 80 ° C. and not higher than 95 ° C. and the surface temperature at the time of transverse stretching is controlled to be not lower than 90 ° C. and not higher than 105 ° C. to set the transverse stretching magnification within the range of 3.3 times to 4.8 times A transverse stretching process for controlling the transverse stretching process,

And a heat fixation step of thermally fixing the polyester film after the transverse stretching step by heating to the maximum temperature in the transverse stretching apparatus,

A method for producing a polyester film having a thickness of 40 to 500 占 퐉.

<14> In the transverse stretching step, the surface temperature is gradually raised at a temperature raising rate of 60 ° C./min or less to set the surface temperature at 80 ° C. or higher and 92 ° C. or lower when the transverse stretching magnification is in the range of 1 × to 2 × , The surface temperature when the transverse stretching magnification is in the range of 2 times or more and 3 times or less is controlled to be 85 占 폚 or more and 97 占 폚 or less and the surface temperature when the transverse stretching magnification is 3 times or more is controlled to be 90 占 폚 or more and 102 占 폚 or less &Lt; 13 >.

<15> A process for producing a polyester film according to <15>, wherein the rate of temperature rise of the surface temperature of the polyester film from the end of the transverse stretching process to the maximum temperature in the heat setting process is controlled to 1000 ° C./min or less, The polyester film according to any one of < 13 > or &lt; 14 &gt;, wherein the maximum arrival surface temperature of the film is controlled to 130 deg. C or higher and 230 deg. C or lower so that the surface temperature of the polyester film exceeds 130 deg. Way.

<16> A process for producing a polyester film according to any one of <13> to <15>, further comprising a heat relaxation step of heating the polyester film after the heat fixation step and reducing the length of the polyester film at least in the transverse direction Way.

<17> A process for producing a polyester film according to any one of <13> to <16>

And a step of laminating a hard coat layer on at least one side of the polyester film.

According to the present disclosure, there is provided a polyester film in which a concave portion is less likely to be generated even when a load is locally applied in the thickness direction of the film, and a method of manufacturing the same.

Further, according to the present disclosure, there is provided a hard-coated film and a method for producing the hard-coated film, in which cracking and peeling of the hard-coat layer are less likely to occur when a hard-coated film obtained by laminating a hard- .

Further, according to the present disclosure, an image display apparatus and a touch panel in which a decrease in visibility due to irregularity in iridescence is suppressed even if a locally applied load is applied to a display screen is provided.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing an example of a cutting blade used in a method of measuring the normal stress on the front face and the yield stress on the front face of the film surface layer. Fig.
Fig. 2 is a schematic view for explaining a method of measuring the normal stress on the front surface and the yield stress on the front surface of the film surface layer.
3 is a schematic view showing an example of the configuration of the transverse drawing apparatus.

Hereinafter, the present disclosure will be described in detail. Descriptions of the constituent elements described below may be made based on representative embodiments or specific examples, but the present disclosure is not limited to such embodiments. In the present specification, the numerical range indicated by using "~" means a range including numerical values written before and after the "~ " as a lower limit value and an upper limit value. In the case where a unit is attached to one of the numerical values described before and after "~", it means that the whole numerical range is the same unit.

[Polyester film]

The polyester film (hereinafter also simply referred to as "film") according to the present embodiment has a thickness of 40 to 500 mu m, and has a vertical front stress A in the slow axis direction in the surface layer of 1 mu m, And the average value of the vertical cross-sectional normal stress B in the orthogonal direction is 30 to 100 MPa.

Here, the "slow axis direction" of the film is a direction in which the refractive index becomes maximum in the film plane, and the direction orthogonal to the slow axis direction in the film plane is also referred to as "fast axis direction ".

The method for producing the polyester film according to the present embodiment will be described in detail later. For example, the polyester resin composition is melt-extruded in the form of a film and then transported using a roll or the like, (Also referred to as the width direction or the transverse direction of the film) perpendicular to the longitudinal direction of the film (also referred to as the longitudinal direction or the longitudinal direction of the film), the width direction of the film is generally the slow axis direction. In the case of producing a polyester film as described above, the transport direction of the film is referred to as MD (Machine Direction), and the direction orthogonal to the transport direction of the film is referred to as TD (Transverse Direction).

&Lt; Characteristic of polyester film >

(thickness)

The thickness of the polyester film according to the present embodiment is 40 to 500 占 퐉.

When the thickness of the polyester film is 40 탆 or more, it has sufficient rigidity and is easy to use as a substitute material for glass. When the thickness is 500 탆 or less, rigidity is not excessively strong, and the punching property and handling property of the film are good.

From this viewpoint, the thickness of the polyester film according to the present embodiment is more preferably 60 to 400 占 퐉, and more preferably 80 to 300 占 퐉.

The thickness of the polyester film according to the present embodiment is measured by, for example, a contact type film thickness meter at 50 points in the direction of the slow axis of the film and in the direction perpendicular to the slow axis direction within the film plane, The average thickness of the measured values of the thickness at these points is determined to be the thickness of the polyester film.

(Shear vertical stress)

The polyester film according to the present embodiment is characterized in that the average vertical stress A in the slow axis direction in the surface layer of 1 mu m and the shear normal stress B in the direction orthogonal to the slow axis direction in the film surface Quot; vertical cross-sectional normal stress ") is 30 to 100 MPa. Here, "surface layer 1 m" means a region from the surface of the polyester film to a depth of 1 m.

When the surface layer average normal shear vertical stress at a surface layer of 1 m is 30 MPa or more, when a hard coat layer is laminated on a polyester film to form a hard coat film, when the film is pressed with a strong force, recesses are hardly generated in the film, , It is difficult for the hard coat layer to crack or peel off when it is formed into a hard coat film.

From this point of view, the polyester film according to the present embodiment has a surface layer average shear vertical stress of preferably 40 to 90 MPa, more preferably 50 to 80 MPa.

In the polyester film according to the present embodiment, it is preferable that the ratio (A / B) of the shear vertical stress A to the shear vertical stress B is 1.1 to 2.0.

If the ratio A / B of the vertical cross-section vertical stress of the polyester film according to the present embodiment is 1.1 or more, the uniaxially oriented polyester film in which rainbow unevenness is suppressed can be easily produced easily. If the polyester film is 2.0 or less, When the coat layer is laminated to form a hard coat film, cracking or peeling hardly occurs in the hard coat layer.

From this point of view, the ratio A / B of the normal shear vertical stress of the polyester film according to the present embodiment is more preferably 1.2 to 1.9, and further preferably 1.3 to 1.8.

(Shear yield stress)

The polyester film according to the present embodiment is characterized in that the average value of the yield stress of the front end face in the slow axis direction in the surface layer of 1 mu m and the shear yield stress in the direction perpendicular to the direction of the slow axis in the film plane Yield stress ") is preferably 20 to 60 MPa. When the surface layer average shear yield stress of the polyester film according to the present embodiment is 20 MPa or more, when the hard coat layer is laminated on the polyester film to form a hard coat film, it is difficult to generate concave portions in the film even when the film is pressed with a strong force If it is 60 MPa or less, it is difficult for the hard coat layer to be cracked or peeled off when the hard coat film is formed.

From this point of view, the surface layer average shear yield stress of the polyester film according to the present embodiment is more preferably 25 to 55 MPa, and still more preferably 30 to 50 MPa.

Here, measurement of the normal stress on the front surface of the film and the shear yield stress of the film in the present embodiment will be described. Figs. 1 and 2 are schematic views for explaining a method of measuring the normal stress on the front surface and the yield stress of the front surface of the film surface layer. Fig. The measuring device, the measurement conditions, the calculation method of the normal shear stress and shear yield stress are as follows.

(1) Measuring devices

In the present embodiment, surface normal and front end yield stresses of the surface layer of the film are measured using SAICAS (Surface Interfacial Cutting Analysis System) -N type (manufactured by Dai-ichi PureTins Co., Ltd.). SAICAS can control the cutting blade speed to monitor the vertical force (F _v ) and horizontal force (F _H ) applied to the cutting blade (10) and the vertical displacement (d) of the cutting blade.

(2) Measurement conditions

First, the inclination angle? And the clearance angle (cutting angle)? Of the cutting blade 10 with respect to the surface of the film 12 are set at predetermined angles, and the cutting blade is inserted into the film 12 from the film surface into the inside thereof 1 (A)).

Shear fracture occurs due to cutting by the cutting blade 10, and the cutting force is monitored (Fig. 1 (B)).

The film 12 was cut to a depth of 1 mu m in the surface layer to evaluate the stress (film strength) acting on the front end face (Fig. 1 (C)).

Here, the measurement conditions are as follows.

· Cutting speed: horizontal speed 100 nm / s, vertical speed 10 nm / s

· Blade width: 0.1mm

· Incline angle (α): 20 °

· Cutting angle (γ): 10 °

· Blade type: Diamond cutting blade

· Direction: measured in the direction of the ground axis and the direction of the leading axis (TD, MD), respectively.

· Measure 3 points at intervals of 10 mm along each direction, and use the mean value as the value in each direction

(3) Calculation of normal shear stress and shear yield stress

2 shows the direction of a force acting when a sample (polyester film) 12 is cut at a cutting angle? In the order of FIGS. 1A to 1C using a cutting blade having an inclination angle? . The force F _S acting parallel to the sample front face AB and the force F _N acting perpendicularly are measured using the horizontal force F _H , the normal force F _V and the shear angle? (1).

Equation (1)

[Equation 1]

Shear surface stresses acting parallel to (in FIG. 2, if indicated by the broken line AB) (τ _s; front end surface yield stress), a stress acting in the vertical (σ _s; front end surface normal stress) is, F _S and F _N is divided by the area A _s of the front cross section and is obtained by the following equation (2), respectively. B is the blade width, and d is the cutting depth (vertical displacement).

Equation (2)

&Quot; (2) &quot;

Further, the shear angle [phi] is obtained by the following equation (3) using the inclination angle [alpha] and the friction angle [beta].

Equation (3)

&Quot; (3) &quot;

That is, by calculating the shear angle α from the horizontal force F _H and the vertical force F _{V at} each depth, the depth direction distribution of the shear yield stress τ _s or the shear vertical stress σ _s is calculated can do.

The polyester film according to the present embodiment is preferably a uniaxially oriented polyester film. It is easy to obtain a polyester film having the above-mentioned thickness and vertical normal stress on the cross section by transversely stretching and thermally fixing the unstretched polyester film obtained by melt film formation or solution film formation by the below-mentioned method.

-Re (retardation in the film plane) -

The polyester film according to the present embodiment preferably has retardation Re in the film plane at a measurement wavelength of 589 nm of 4000 to 50,000 nm.

If the Re of the polyester film according to this embodiment is 4000 nm or more, irregularity of iridescence is hardly visible. If it is 50000 nm or less, necessary film thickness is not excessively thickened, and excessively strong stiffness is suppressed and handling is facilitated.

From this viewpoint, the Re of the polyester film according to the present embodiment at a measurement wavelength of 589 nm is more preferably 5000 to 40000 nm, and more preferably 7000 to 33000 nm.

-Re / Rth-

In the polyester film according to the present embodiment, it is preferable that the ratio (Re / Rth) of the retardation Re in the film plane to the retardation Rth in the film thickness direction at the measurement wavelength of 589 nm is 0.6 to 1.2.

When the Re / Rth of the polyester film according to the present embodiment at a measurement wavelength of 589 nm is 0.6 or more, unevenness in iridescence is hardly visible. When the Re / Rth is 1.2 or less, the film is unlikely to be broken.

From this point of view, the Re / Rth of the polyester film according to the present embodiment is more preferably 0.7 to 1.15, and more preferably 0.8 to 1.1.

The retardation Rth in the thickness direction of the polyester film according to the present embodiment at a measurement wavelength of 589 nm is preferably from 3,000 to 80,000 nm, more preferably from 4,000 to 60,000 nm, and still more preferably from 6,000 to 40,000 nm. When the Rth is 3000 nm or more, it is easy to form a film, and when it is 80000 nm or less, irregularity of iridescence is hardly generated on the screen when the hard coat film using the polyester film according to the present embodiment is applied to, for example, .

The irregularity of iridescence can reduce the Nz value indicating the relationship between Re and Rth to an appropriate value. From the effect of reduction of irregularity of irregularity and the suitability for production, the Nz value is preferably not more than 2.0, preferably 0.5 to 2.0 More preferably 0.5 to 1.5.

Since iridescence occurs due to incident light, it is usually observed at the time of white display.

The retardation Re in the film plane of the polyester film according to the present embodiment is represented by the following formula (4).

Equation (4): Re = (nx -ny) × y 1

Here, nx is the refractive index in the in-plane slow axis direction of the polyester film, ny is the refractive index in the in-plane fast axis direction (direction perpendicular to the in-plane slow axis direction) of the polyester film, and y ₁ is the thickness of the polyester film .

The retardation Rth in the thickness direction of the polyester film according to the present embodiment is represented by the following formula (5).

Equation (5): Rth = {( nx + ny) / 2-nz} × y 1

Here, nz is the refractive index in the thickness direction of the polyester film.

The Nz value of the polyester film is represented by the following formula.

Nz = (nx-nz) / (nx-ny)

In the present specification, Re, Rth and Nz at the wavelength? Nm can be measured as follows.

Using two polarizing plates, the orientation axis direction (the slow axis direction and the fast axis direction) of the polyester film is determined, and a rectangle of 4 cm x 2 cm is cut so that the alignment axis direction is orthogonal to obtain a sample for measurement. The refractive index (Nx, Ny) and the refractive index (Nz) in the thickness direction of the sample were measured by Abbe's refractometer (manufactured by Atago Co., Ltd., NAR-4T, measurement wavelength: 589 nm) (| Nx-Ny |) is defined as anisotropy (? Nxy) of the refractive index. The thickness y ₁ (nm) of the polyester film was measured using an electric micrometer (Millitron 1245D, manufactured by Feinpruf GmbH), and the unit was converted to nm. From the measured Nx, Ny, Nz value of a, y ₁ was calculated Re, Rth, Nz, respectively.

The above Re and Rth can be adjusted by the kind of the polyester resin used in the film, the amount of the polyester resin and the additive, the addition of the retardation agent, the film thickness of the film, the stretching direction of the film and the elongation.

The method of controlling the Re and Re / Rth of the polyester film according to the present embodiment within respective ranges is not particularly limited, but can be achieved by, for example, a stretching method.

&Lt; Constituent material, layer composition, and surface treatment of polyester film >

The polyester film according to the present embodiment includes a polyester resin. The mass ratio of the polyester resin in the entire film is generally 50 mass% or more, preferably 70 mass% or more, and more preferably 90 mass% or more.

The polyester film according to the present embodiment may be a single layer film of a layer mainly composed of a polyester resin, or may be a multilayer film having at least one layer mainly composed of a polyester resin.

The polyester film according to the present embodiment may be subjected to surface treatment on both sides or one side of the film. The surface treatment may be a surface modification by a corona treatment, a saponification treatment, a heat treatment, an ultraviolet ray irradiation, an electron beam irradiation or the like, or may be a thin film formation by coating or vapor deposition of a polymer or metal.

The polyester film of this embodiment may have this adhesive layer (easy adhesion layer) on at least one side.

The thickness of the adhesive layer included in the polyester film according to the present embodiment is preferably 30 to 300 nm, more preferably 40 to 200 nm, and still more preferably 50 to 150 nm.

If the thickness of the adhesive layer is 30 nm or more, the cushioning effect by the adhesive layer is easily obtained, and the excessive vertical stress on the front face and the yield stress on the front face are suppressed from rising excessively. When the thickness of the adhesive layer is 300 nm or less, the cushioning effect of the adhesive layer is not excessively strong, so that the vertical stress at the front end face and the yield stress at the front end are prevented from being excessively low.

It is more preferable that the adhesive layer contains particles and the height at which the particles protrude from the surface of the adhesive layer is not less than the thickness of the adhesive layer.

The height at which the particles protrude from the surface of the adhesive layer is an average value at five points in the adhesive layer having a square of 1 mm.

When the height of the particles contained in the adhesive layer protruding from the surface of the adhesive layer is lower than the thickness of the adhesive layer (preferably, the coating layer), the sliding property is lowered and wrinkles tend to be easily generated .

The kind of the particles is not particularly limited and specific examples include particles of silica, calcium carbonate, magnesium carbonate, valium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, titanium oxide, zirconium oxide, And is preferably silica, aluminum oxide, titanium oxide, or zirconium oxide. Heat resistant organic particles described in JP-A-59-5216 and JP-A-59-217755 may also be used. Examples of the other heat-resistant organic particles include a thermosetting urea resin, a thermosetting phenol resin, a thermosetting epoxy resin, and a benzoguanamine resin.

Regarding the particle size, it is preferable that the height at which the particles protrude from the surface of the adhesive layer is larger than the thickness of the adhesive layer. It is preferable to use particles adjusted to the primary average particle diameter. However, the resultant particles may be aggregated so that the height at which the particles protrude from the surface of the adhesive layer is not less than the thickness of the adhesive layer. In the case of aggregated particles, the height at which the particles protrude from the surface of the adhesive layer can be determined by measuring the secondary average particle diameter.

(1-1) Polyester resin

As the polyester resin included in the polyester film according to the present embodiment, for example, a polyester resin having a composition of WO2012 / 157662 is preferably used.

As the specific polyester resin, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polystyrene terephthalate (PBT), polycyclohexanedimethylene terephthalate (PCT) and the like can be used. PET and PEN are more preferable, and PET is more preferable. In addition, PEN is apt to have a small Re / Rth.

As the polyester resin, polyethylene terephthalate is most preferable, but polyethylene naphthalate is also preferably used. For example, polyethylene naphthalate described in JP-A-2008-39803 can be preferably used.

Polyethylene terephthalate is a polyester having a constituent unit derived from terephthalic acid as a dicarboxylic acid component and a constituent unit derived from ethylene glycol as a diol component, and 80 mol% or more of all the repeating units are ethylene terephthalate And may contain a constituent unit derived from another copolymerizable component. Examples of other copolymerization components include isophthalic acid, p- beta -oxyethoxybenzoic acid, 4,4'-dicarboxy diphenyl, 4,4'-dicarboxybenzophenone, bis (4-carboxyphenyl) Dicarboxylic acid components such as sebacic acid, 5-sodium sulfoisophthalic acid, and 1,4-dicarboxycyclohexane, propylene glycol, butanediol, neopentylglycol, diethylene glycol, cyclohexane Diol, an ethylene oxide adduct of bisphenol A, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. These dicarboxylic acid components and diol components may be used in combination of two or more kinds, if necessary. It is also possible to use an oxycarboxylic acid such as p-oxybenzoic acid together with the carboxylic acid component or the diol component. As the other copolymerization component, a dicarboxylic acid component and / or a diol component containing a small amount of an amide bond, a urethane bond, an ether bond, a carbonate bond or the like may be used.

Examples of the method for producing polyethylene terephthalate include so-called direct polymerization methods in which terephthalic acid and ethylene glycol are reacted directly with other dicarboxylic acids and / or other diols as needed, dimethylester of terephthalic acid and ethylene glycol, An ester exchange reaction method in which a dimethyl ester of a dicarboxylic acid and / or another diol is subjected to an ester exchange reaction can be applied.

(1-2) Properties of polyester resin

(1-2-1) Intrinsic viscosity

The intrinsic viscosity (IV) of the polyester resin is preferably 0.5 or more and 0.9 or less, more preferably 0.52 or more and 0.8 or less, and still more preferably 0.54 or more and 0.7 or less. In order to achieve such IV, solid phase polymerization may be used in combination with the melt polymerization to be described later in the synthesis of the polyester resin.

(1-2-2) Content of acetaldehyde

The acetaldehyde content of the polyester resin is preferably 50 ppm or less. More preferably 40 ppm or less, particularly preferably 30 ppm or less. Acetaldehyde easily causes a condensation reaction between acetaldehyde and water as an adduct, and the water sometimes causes hydrolysis of the polyester. The lower limit of the acetaldehyde content is practically 1 ppm. In order to keep the acetaldehyde content within the above-mentioned range, it is necessary to keep the oxygen concentration in each step such as melt polymerization and solid phase polymerization at the time of production of the resin low, to keep the oxygen concentration at the time of drying, A method may be employed in which strong thermal shearing is not applied locally by, for example, lowering the thermal history applied to the resin by an extruder, melt pipe, die or the like, or screwing the extruder at the time of melting.

(1-3) Catalyst

Sb, Ge, Ti, and / or Al-based catalysts are used for polymerization of the polyester resin, preferably Sb, Ti, and / or Al-based catalysts, and more preferably Al-based catalysts.

That is, the polyester resin used as the raw material resin is preferably a resin obtained by polymerization using an aluminum catalyst.

By using the Al-based catalyst, Re is more likely to be expressed than in the case of using another catalyst (for example, Sb or Ti), and the thickness of the PET can be reduced. That is, the use of an Al-based catalyst means that the orientation is easy. This is presumed to be due to the following reasons.

Al-based catalysts have lower reactivity (polymerization activity) as compared with Sb-based catalysts or Ti-based catalysts, so that the reaction is mild and a by-product (diethylene glycol unit: DEG) is hardly produced.

As a result, the regularity of the PET is enhanced, and Re is easy to be easily oriented.

(1-3-1) Al-based catalyst

As the Al-based catalyst, Al-based catalysts described in [0013] to [0148] (WO2012 / 0183761 [0021] to [0123]) of WO2011 / 040161 can be used and the contents described in these publications are incorporated herein by reference .

The method for producing a polyester resin by polymerization using an Al-based catalyst is not particularly limited, but specific examples thereof include a method of producing a polyester resin by polymerization of [0091] to [0094] ([0144] to [0153] of US2013 / 0112271 in WO2012 / 008488) , And the contents described in these publications are incorporated herein by reference.

Examples of the Al-based catalysts include, for example, those of [0052] to [0054], [0099] to [0104] of WO01212 / 021251 ([0045] to [0047] [0096]), and the contents described in these publications are incorporated herein by reference.

The amount of the Al-based catalyst is preferably from 3 to 80 ppm, more preferably from 5 to 60 ppm, and even more preferably from 5 to 40 ppm, as the amount of the Al element to the mass of the polyester resin.

(1-3-2) Sb catalyst:

As the Sb-based catalyst, Sb-based catalysts described in [0050], [0052] - [0054] of JP-A No. 2012-41519 can be used.

The method of polymerizing the polyester resin using the Sb-based catalyst is not particularly limited, but specifically, polymerization can be carried out according to WO 00/121257662 [0086] to [0087].

(1-4) Additive:

It is also preferable to add a known additive to the polyester film of the present embodiment. Examples thereof include an ultraviolet absorber, a particle, a lubricant, an antiblocking agent, a heat stabilizer, an antioxidant, an antistatic agent, an antioxidant, an impact resistance improver, a lubricant, a dye and a pigment. However, since the polyester film generally requires transparency, the addition amount of the additive is preferably minimized.

(1-4-1) Ultraviolet (UV) absorbing agent:

The polyester film according to this embodiment may contain an ultraviolet absorber to prevent the liquid crystal of the liquid crystal display from being deteriorated by ultraviolet rays. The ultraviolet absorber is not particularly limited as long as it is a compound capable of absorbing ultraviolet light and is capable of withstanding the heat added in the process for producing a polyester film.

As the ultraviolet absorber, there are an organic ultraviolet absorber and an inorganic ultraviolet absorber, and from the viewpoint of transparency, an organic ultraviolet absorber is preferable. An ultraviolet absorber described in WO2012 / 157662 or a cyclic iminoester ultraviolet absorber described below may be used.

Examples of the cyclic iminoester ultraviolet absorber include, but are not limited to, 2-methyl-3,1-benzoxazine-4-one, 2-butyl-3,1-benzoxazine- , 2- phenyl-3,1-benzoxazine-4-one, 2- (1- or 2-naphthyl) -3,1- 2-m-nitrophenyl-3,1-benzoxazine-4-one, 2-p-nitrophenyl- 2-p-benzoylphenyl-3,1-benzoxazine-4-one, 2-p-methoxyphenyl- , 2-cyclohexyl-3,1-benzoxazine-4-one, 2-p- (or m-) phthalimidophenyl-3,1-benzoxazine- Benzoyl-4- (3,1-benzoxazin-4-one-2-yl) 2-yl) aniline, 2- (p- (N-methylcarbonyl) phenyl) -3-benzyloxycarbonylamino- , 2,2'-bis (3,1-benzoxazine-4-one), 2,2'-ethylenebis (3,1- ), 2,2'-tetramethylenebis (3,1-benzoxazine-4-one), 2,2'-ethylenebis Phenol) bis (4H-3,1-benzoxazine-4-one) (also referred to as 2,2'-p-phenylenebis (3,1-benzoxazine- , 2,2'-m-phenylenebis (3,1-benzoxazine-4-one), 2,2 '- (4,4'- (2,2 '- (2-methyl-thiazol-2-yl) benzooxazin-4-one), 2,2'- (2-nitro-p-phenylene) bis (3,1- , 2,2 '- (1,4-cyclohexylene) bis (3,1-benzoxazin-4-one) Benzooxazin-4-one), 1,3,5-tri (3,1-benzoxazine-4-one-2-yl) benzene, 1,3,5- 2-yl) naphthalene, 2,4,6-tri (3,1-benzoxazine-4-on-2-yl) naphthalene, 2,8- (1,2-d; 5,4-d ') bis (1,3) -oxazine-4,6-dione, 2,7-dimethyl-4H, 9H- 4,5-d ') ratio (1,3) -oxazine-4,9-dione, 2,8-diphenyl-4H, 8H-benzo (1,2- Photo-4,6-dione, 2,7-diphenyl-4H, 9H-benzo (1,2-d; 4,5-d ') bis Ion, 6,6'-bis (2-methyl-4H, 3,1-benzoxazine-4-one), 6,6'- (2-phenyl-4H, 3,1-benzoxazine-4-one), 6,6'-methylenebis (2-methyl-4H, 3-benzothiophene-4-one), 6,6'-methylenebis Benzooxazin-4-one), 6,6'-ethylene bis (2-phenyl-4H, 3,1- 4H, 3,1-benzoxazine-4-one), 6,6'-butylene bis (2-phenyl- (2-methyl-4H, 3,1-benzoxazine-4-one), 6,6'-oxybis (2-methyl-4H, 3,1-benzoxazine-4-one), 6,6'-sulfonylbis -One), 6,6'-carbonylbis (2-methyl-4H, 3,1-benzoox 4-one), 6,6'-carbonylbis (2-phenyl-4H, 3,1-benzoxazine- Benzooxazin-4-one), 7,7'-methylenebis (2-phenyl-4H, 4H, 3,1-benzoxazine-4-one), 7,7'-ethylene bis (2-methyl- 2-methyl-4H, 3,1-benzoxazine-4-one), 7,7'-sulfonylbis (2-methyl-4H, 3,1-benzoxazine-4-one), 6,7'-bis , 6,7'-bis (2-phenyl-4H, 3,1-benzoxazine-4-one, 6,7'- methylenebis On), 6,7'-methylenebis (2-phenyl-4H, 3,1-benzoxazine-4-one) and the like.

Among the above compounds, benzooxanthone compounds which are difficult to exhibit yellow color are suitably used in consideration of the color tone, and for example, compounds represented by the following formula (6) are more suitably used.

Equation (6)

[Chemical Formula 1]

In the formula (6), R represents a divalent aromatic hydrocarbon group, and X ¹ and X ² are each independently selected from the group consisting of a hydrogen atom or the following functional groups, but are not limited thereto.

Functional group group: an alkyl group, an aryl group, a heteroaryl group, a halogen, an alkoxyl group, an aryloxyl group, a hydroxyl group, a carboxyl group, an ester group, and a nitro group.

Among the compounds represented by the above formula (6), 2,2 '- (1,4-phenylene) bis (4H-3,1-benzoxazine-4-one) is particularly preferable.

The amount of the ultraviolet absorber contained in the polyester film according to the present embodiment is usually 10.0 mass% or less, preferably 0.3 to 3.0 mass%, based on the entire film. When an ultraviolet absorbent in an amount exceeding 10.0% by mass is contained, the ultraviolet absorber may bleed out on the surface, resulting in a decrease in the functionality of the surface, such as deterioration in adhesiveness.

When the polyester film according to the present embodiment has a laminated structure, it is preferable that the polyester film has at least a three-layer structure, and the ultraviolet absorber is preferably blended in an intermediate layer (a layer other than the outermost layer). By blending an ultraviolet absorber in the intermediate layer, it is possible to prevent the ultraviolet absorber from bleeding out on the surface of the film, and as a result, properties such as adhesiveness of the film can be maintained.

For the blending of the ultraviolet absorber, for example, a master batch method described in WO 00/1995 to WO 01/162198 can be used.

(1-4-2) Other additives

Other additives may be used for the polyester film according to this embodiment. For example, the additives described in WO 02012/157662 can be used, and the contents described in this publication are incorporated herein by reference.

[Production method of polyester film]

By using a transverse stretching apparatus having a plurality of clips which run along a pair of rails provided on both sides of the film carrying path,

A preheating step of preheating an unoriented or vertically stretched polyester film at a heating rate of 600 DEG C / min or less,

Transversely stretching is performed in such a manner that the both edges of the preheated polyester film are held in a plurality of clips and stretched in a direction orthogonal to the film transport path, and the surface temperature of the polyester film (hereinafter referred to as " The surface temperature at the start of transverse stretching is controlled to be not less than 80 ° C and not more than 95 ° C and the surface temperature at the time of transverse stretching is controlled to be not less than 90 ° C and not more than 105 ° C A transverse stretching step of controlling the transverse stretching magnification within a range from 3.3 times to 4.8 times,

And a heat fixing step of heating and fixing the polyester film after the transverse stretching process to the maximum temperature in the transverse stretching apparatus,

Thereby producing a polyester film having a thickness of 40 to 500 占 퐉.

Here, the term "unstretched polyester film" means a polyester film in which the refractive indexes of both MD and TD are 1.590 or less. For example, even if the MD and TD have a refractive index of MD and TD of 1.590 or less Film and the like are also included in the substantially unstretched polyester film.

Hereinafter, as a preferred embodiment of the method for producing a polyester film according to the present embodiment, there will be described a case where uniaxially oriented polyester film is formed by melt extrusion and then stretched in the transverse direction to produce a uniaxially oriented polyester film do.

<Melt kneading>

It is preferable that an unstretched polyester film is formed into a film by melt extrusion of a polyester resin.

It is preferable that the master batch of the polyester resin or the polyester resin produced by the master batch method described above and the additive is dried at a water content of 200 ppm or less and then introduced into a single screw or biaxial extruder for melting. At this time, in order to suppress the decomposition of the polyester resin, it is also preferable to melt in nitrogen or in vacuum. The detailed conditions can be implemented in accordance with these publications by adopting, for example, [0051] - [0052] of US Patent No. 4962661 ([0085] - [0086] of US2013 / 0100378) Which is incorporated herein by reference. It is also preferable to use a gear pump in order to increase the feeding accuracy of the molten resin (melt). It is also preferable to use a filter having a pore diameter of 3 占 퐉 to 20 占 퐉 for removal of impurities.

<Extrusion or coextrusion>

Although it is preferable to extrude the melt containing the melt-kneaded polyester resin from the die, it may be extruded as a single layer or may be extruded (co-extruded) into multiple layers. In the case of multilayer extrusion, for example, a layer containing a UV absorber (UV agent) and a layer not containing an ultraviolet absorber (UV agent) may be laminated. More preferably, a three- It is preferable to suppress the deterioration of the polarizer by the UV rays and to suppress the bleed out of the UV rays.

The UV agent that bleeds out is not preferable because the UV agent is transferred to a roll on which the film is in contact during the production process of the film, and the coefficient of friction between the film and the roll is increased to cause scratches.

In the case where the polyester film is produced by extruding into a multilayer, the thickness (ratio to the total layer) of the preferable inner layer (the layer other than the outermost layer) of the obtained polyester film is preferably 50% or more and 95% or less, Is not less than 60% and not more than 90%, and more preferably not less than 70% and not more than 85%. Such lamination can be performed by using a feed block die or a multi-manifold die.

<Cast>

For example, in accordance with [0059] of JP-A-2009-269301, it is preferable to extrude the melt extruded from a die onto a casting drum and cool and solidify to obtain an unstretched polyester film (master).

In the method for producing a polyester film according to the present embodiment, the refractive index in the longitudinal direction (MD) of the unstretched polyester film is preferably 1.590 or less, more preferably 1.585 or less, still more preferably 1.580 or less.

In the method for producing a polyester film according to the present embodiment, the crystallinity of the unstretched polyester film is preferably 5% or less, more preferably 3% or less, and further preferably 1% or less. The term "degree of crystallization of an unoriented polyester film" as used herein means the degree of crystallization in the central portion of the film width direction (TD).

When the crystallinity is adjusted, the temperature of the end of the casting drum may be lowered or the casting drum may be blown on the casting drum.

The crystallinity can be calculated from the density of the film. That is, the density of the film X (g / cm ^3), crystallinity (%) from density Y = 1.335g / cm ^3, to calculation using a density Z = 1.501g / cm ³ at 100% crystallinity in the degree of crystallinity 0% Can be derived.

Crystallinity = {Z x (X-Y)} / {X x (Z-Y)} x 100

The density is measured in accordance with JIS K7112.

&Lt; Formation of polymer layer >

The polyester film to be subjected to melt extrusion may be formed by applying a polymer layer according to the purpose before or after the stretching described later.

As the polymer layer, a functional layer which may be generally contained in a polarizing plate may be mentioned, and it is preferable to form the adhesive layer. This adhesive layer can be applied (coated) by the method described in, for example, [0062] to [0070] of WO2012 / 157662.

<Preheating>

Fig. 3 schematically shows an example of the configuration of the transverse stretching device used in the transverse stretching step.

As the preheating step up to the start of the stretching in the transverse stretching step, it is preferable to preheat the non-stretched polyester film at a heating rate of 600 DEG C / min or less. When the rate of temperature rise of the film up to the start of the stretching in the transverse stretching process is 600 ° C / min or less, the stretching takes place in a state in which the molecular chain starts to move sufficiently, and the normal shear stress and shear yield stress are excessively increased .

From this viewpoint, the heating rate in the preheating step is more preferably 500 ° C / min or less, and more preferably 400 ° C / min or less.

The rate of temperature rise in the preheating step may be 40 ° C / min or more and 600 ° C / min or less, 40 ° C / min or more and 500 ° C / min or less, or 40 ° C / min or more and 400 ° C / min or less.

<Transverse stretching>

In the transverse stretching process, as shown in Fig. 3, a transverse stretching device (also referred to as a "tenter stretching device" or "tenter") having a plurality of clips 20 running along a pair of rails provided on both sides of the film- ), Transversely stretching is performed in a state in which both edges of the unstretched polyester film are gripped by the clip 20, respectively. Further, the unstretched polyester film may be gripped with a clip at the stage of the preheating process.

The transverse stretching device having the clip 20 running along a pair of rails provided on both sides of the film carrying path is not particularly limited. A pair of rails is usually a pair of endless rails. Further, the clip is in agreement with the holding member.

The non-stretched polyester film is stretched transversely. The transverse stretching is performed in a direction (TD) orthogonal to the film transport direction (MD) while the unstretched polyester film is transported along the film transport path. In other words, transverse stretching can be achieved by gripping both ends of the film with clips and enlarging the width between the clips while heating.

By transversely stretching, the retardation Re in the in-plane direction can be largely expressed. In particular, in order to achieve a polyester film satisfying a preferable range of Re and Re / Rth, it is preferable to perform transverse stretching at least. The longitudinal stretching may be performed before the preheating process or before the transverse stretching process.

The surface temperature at the start of the stretching in the transverse stretching step is preferably 80 占 폚 or higher and 95 占 폚 or lower, more preferably 82 占 폚 or higher and 93 占 폚 or lower, and still more preferably 84 占 폚 or higher and 92 占 폚 or lower.

If the surface temperature at the start of stretching in the transverse stretching process is 80 占 폚 or more, orientation and orientation crystallization do not progress excessively in the stretching step, and excessive increase in the normal shear vertical stress and shear yield stress is suppressed. Further, the rise of Rth is suppressed, and the Re / Rth ratio becomes 0.6 or more, so that the visibility of iridescence is suppressed.

If the surface temperature at the start of stretching in the transverse stretching process is 95 캜 or less, the growth of spherical crystals due to the lack of orientation is suppressed, the vertical stress at the front end and the shear yield stress at the front end excessively fall, Cloudiness is suppressed, and Re is liable to rise sufficiently.

In the method for producing a polyester film according to the present embodiment, the surface temperature at the end of the stretching in the transverse stretching step is preferably 90 占 폚 or more and 105 占 폚 or less, more preferably 92 占 폚 or more and 102 占 폚 or less, Or more and 100 DEG C or less is more preferable.

If the surface temperature at the end of the stretching in the transverse stretching step is 90 DEG C or more, orientation and orientation crystallization do not proceed excessively in the stretching step, and excessive increase in the normal shear vertical stress and shear yield stress is suppressed. Further, the rise of Rth is suppressed, and the Re / Rth ratio becomes 0.6 or more, so that the visibility of iridescence is suppressed.

If the surface temperature at the end of the stretching in the transverse stretching step is 105 DEG C or lower, the growth of the Chinese New Year due to the lack of orientation is suppressed, the vertical stress at the front surface and the shear yield stress at the front end excessively fall, And the Re which influences the suppression of the irregularity of the irregularity is likely to rise sufficiently.

The surface temperature is gradually increased from the start of drawing to the end of drawing in the transverse drawing step. Here, "gradually increase" may be continuously raised or may be increased stepwise.

The difference in surface temperature between the end of drawing and the start of drawing is preferably 1 占 폚 or higher, more preferably 3 占 폚 or higher, and most preferably 5 占 폚 or higher.

If the surface temperature is gradually increased from the start of the stretching to the end of the stretching, it is more difficult to form the glass and the orientation is prevented from being excessively advanced, and both Re and Re / Rth are easily compatible with each other in a preferable range. .

The transverse stretching magnification in the transverse stretching step is preferably controlled within the range of 3.3 times to 4.8 times, more preferably 3.5 times to 4.5 times, and more preferably 3.7 times to 4.3 times.

If the transverse stretching magnification is 3.3 times or more, excessive vertical stress and shear yield stress of the film are suppressed from being excessively lowered, and reduction of Re, which is effective in suppressing irregularity of iridescence, is suppressed. When the transverse stretching magnification is 4.8 times or less, the vertical stress of the front surface of the film and the shear yield stress of the film excessively increase, and the breaking is suppressed.

In the transverse stretching step, when the transverse stretching magnification is in the range of 1 to 2 times, the surface temperature is preferably 80 to 92 deg. C, more preferably 82 to 91 deg. C, and more preferably 84 to 91 deg. Or less.

When the transverse stretching magnification is in the range of 1 to 2 times the surface temperature, if the surface temperature is 80 DEG C or more, the orientation and orientation crystallization do not proceed excessively in the stretching step, and the vertical cross- Is prevented from rising excessively. Further, the rise of Rth is suppressed, and the Re / Rth ratio becomes 0.6 or more, and the visibility of the irregularity of the irregularity is suppressed.

If the surface temperature when the transverse stretching magnification in the transverse stretching process is in the range of 1 times to 2 times or less is 92 占 폚 or less, the growth of the glass due to the lack of orientation is suppressed and the normal vertical stress and shear yield stress And the Re is not sufficiently raised, thereby suppressing the irregularity of the irregularity.

In the transverse stretching step, the surface temperature when the transverse stretching magnification is in the range of 2 times or more and 3 times or less is preferably from 85 占 폚 to 97 占 폚, more preferably from 86 占 폚 to 97 占 폚, and from 87 占 폚 to 96 占 폚 Or less.

In the transverse stretching step, when the surface temperature is 85 ° C or more when the transverse stretching magnification is in the range of 2 times or more and less than 3 times, the orientation and orientation crystallization do not proceed excessively in the stretching step, Is prevented from rising excessively. Also, the rise of Rth is suppressed, and the Re / Rth ratio becomes 0.6 or less, and the visibility of the irregularity of the irregularity is suppressed.

In the transverse stretching process, when the surface temperature is 97 占 폚 or less when the transverse stretching magnification is in the range of 2 to 3 times, the growth of the reclamation due to the lack of orientation is suppressed and the normal shear stress and shear yield stress The overdrive is suppressed. In addition, Re which is effective in suppressing irregularity of iridescence is sufficiently raised, and irregularity of iridescence is suppressed.

In the transverse stretching step, the surface temperature when the transverse stretching magnification is in the range of 3 times or more is preferably 90 占 폚 or more and 102 占 폚 or less, more preferably 92 占 폚 or more and 101 占 폚 or less, more preferably 93 占 폚 or more and 100 占 폚 or less Do.

If the surface temperature when the transverse stretching magnification is in the range of 3 times or more in the transverse stretching step is 90 占 폚 or more, the orientation and orientation crystallization are not excessively advanced in the stretching step, and the vertical cross- . In addition, the rise of Rth is suppressed, and the Re / Rth ratio becomes 0.6 or more, whereby the irregularity of the iridescence is suppressed.

In the transverse stretching step, when the surface temperature when the transverse stretching magnification is in the range of 3 times or more is 102 占 폚 or less, the growth of the Chinese New Year due to the lack of orientation is suppressed and the vertical stress at the front face and the front end yield stress are excessively lowered . Also, Re is sufficiently raised to suppress the visibility of iridescence.

In addition, in the transverse stretching step, the surface temperature and the transverse stretching magnification are preferably not less than two times or more when the transverse stretching magnification is in the range of not less than 1 times and not more than 2 times, The surface temperature when the range is less than 3 times and the surface temperature when the transverse stretching magnification is in the range of 3 times or more are not less than the surface temperature of the stretching range in which the transverse stretch magnification is small. That is, the surface temperature when the transverse stretching magnification is in the range of not less than 2 times but not more than 3 times is not less than the surface temperature when the transverse stretching magnification is in the range of not less than 1 times but not more than 2 times, , The surface temperature is not lower than the surface temperature when the transverse stretching magnification is in the range of 2 times or more and less than 3 times.

In the transverse stretching step, the rate of temperature rise of the surface temperature at the time of stretching is preferably 60 ° C / min or less, more preferably 50 ° C / min or less, and further preferably 40 ° C / min or less.

In the transverse stretching step, when the rate of temperature rise of the surface temperature at the time of stretching is 60 DEG C / min or less, the molecular chain is prevented from moving abruptly during stretching, and the vertical cross-section normal stress and cross- . In addition, Re which is effective in suppressing irregularity of iridescence increases sufficiently, and it becomes difficult for irregularity of iridescence to be visually recognized.

In the transverse stretching step, the rate of temperature rise of the surface temperature at the time of stretching is not less than 5 占 폚 / min and not more than 60 占 폚 / min, not less than 5 占 폚 / min and not more than 50 占 폚 / min, do.

<Heat fixation>

And a heat fixation step of thermally fixing the transversely stretched polyester film by heating to the maximum temperature in the transverse stretching apparatus.

After stretching, heat treatment called "heat fixation" is performed to promote crystallization. When the temperature is higher than the stretching temperature, crystallization is promoted, and the strength of the film can be increased.

In heat setting, the volume shrinks for crystallization.

The open and defined method can be achieved by providing a plurality of slits for feeding hot air to the stretching unit in parallel in the width direction and raising the temperature of the gas ejected from the slit above the stretching unit.

Alternatively, a heat source (IR heater, halogen heater, or the like) may be provided near the stretching (sub) outlet to raise the temperature.

The maximum surface temperature of the polyester film in the heat fixation step is preferably 130 ° C to 230 ° C, more preferably 150 ° C to 210 ° C, and more preferably 160 to 200 ° C.

If the maximum surface temperature reached 130 ° C or higher in the heat setting process, excessively lowering of the normal stress on the cross section and the yield stress of the cross section is suppressed, and if the temperature is less than 230 ° C, .

The rate of temperature rise of the surface temperature of the film from the end of the transverse stretching process until reaching the maximum temperature in the heat setting process is preferably 1000 ° C / min or less, more preferably 800 ° C / min or less, Or less.

Here, the "maximum temperature in the heat fixing step" refers to the highest point of the surface temperature reached by the film in the heat fixing zone, and the surface temperature (film surface temperature) of the film in the heat fixing zone is measured by a radiation thermometer Can be obtained.

When the rate of temperature rise of the film in the heat setting step from the end of the transverse stretching process is 1000 캜 / min or less, the relaxation of the molecules is inhibited from proceeding abruptly before crystallization, and the normal shear stress and shear- Re is not sufficiently raised, and rainbow unevenness is suppressed from being recognized.

The rate of temperature rise of the surface temperature of the film from the end of the transverse stretching process to the maximum temperature in the heat setting process is not less than 50 占 폚 / min and not more than 1000 占 폚 / min, not less than 50 占 폚 / min and not more than 800 占 폚 / min, Or 50 ° C / min or more and 700 ° C / min or less.

The time at which the surface temperature exceeds 130 캜 is preferably 180 seconds or less, more preferably 120 seconds or less, and even more preferably 60 seconds or less.

When the surface temperature exceeds 130 占 폚 for 180 seconds or less, the crystallization does not proceed excessively, the vertical cross-section normal stress and the cross-sectional yield stress excessively increase, or Rth excessively increases and rainbow unevenness is suppressed.

The time at which the surface temperature exceeds 130 占 폚 may be 10 seconds or more and 180 seconds or less, 10 seconds or more and 120 seconds or less, or 10 seconds or more and 60 seconds or less.

<Thermal relaxation>

And a heat relaxation step of heating the polyester film after the heat fixing step and reducing the length of the polyester film at least in the transverse direction (TD). In other words, it is preferable that the polyester film after the transverse stretching is heated to the maximum temperature in the transverse stretching apparatus before the transversely stretched polyester film is opened from the clip, and the heat- It is preferable to include a thermal relaxation process for narrowing the distance between rails.

In addition, the heat relaxation process is not limited to the mode in which the heat relaxation process is strictly performed after the heat fixation process, and the heat fixation process and the heat relaxation process may be performed at the same time. In the case where the heat fixing step and the heat relaxation step are performed at the same time, the heat fixing step from the point of time of heating up to the maximum temperature in the transverse drawing apparatus is continued, and the heat relaxation is continued at a temperature not exceeding the maximum temperature in the transverse drawing apparatus desirable.

It is preferable to perform relaxation (shrink the film) simultaneously with the heat treatment after the heat fixation step, and it is preferable to perform at least one of TD (transverse direction) and MD (longitudinal direction).

The lateral relaxation can be achieved by reducing the width of the clip in which the width is enlarged.

Such relaxation can be achieved by, for example, reducing the interval of the pantograph by using a pantograph-shaped chuck in the tenter, or by driving the clip on the electromagnet to lower the speed.

In the thermal relaxation step, it is preferable that the relaxation rate of MD, which is the rate of reducing the MD length of the heat-set polyester film, is 1 to 7% from the viewpoint of suppressing the occurrence of scratches on the polyester film, %, More preferably 3 to 5%. If the relaxation rate of the MD is 1% or more, the heat shrinkage ratio of the MD can be reduced, and wrinkles are less likely to occur. If the relaxation rate of the MD is 7% or less, it is difficult for the MD to be sagged during the relaxation treatment, and it is difficult for the surface to be broken.

It is preferable that the relaxation rate of TD, which is the rate of decreasing the TD length of the heat-set polyester film, is 0 to 6% from the viewpoint of suppressing the occurrence of scratches on the polyester film, more preferably 1 to 4% More preferably 1 to 3%. If the relaxation rate of TD is 6% or less, sagging in TD is less likely to occur during the relaxation treatment, and it is difficult for the surface to be broken.

The relaxation temperature in TD (transverse direction) is preferably within the range of the above-mentioned heat fixation temperature, and as long as the heat fixation for heating the transversely stretched polyester film to the maximum temperature in the transverse stretching apparatus can be performed, That is, the maximum temperature in the transverse drawing apparatus).

Re, Rth, and Re / Rth of the polyester film according to the present embodiment can be easily achieved by performing the preheating process, the transverse stretching process, the heat setting process, and the thermal relaxation process as required, It is easy to produce a polyester film according to the present embodiment which exhibits the effect of the present invention.

<Cooling>

It is preferable to include a step of cooling the polyester film before opening the polyester film after heat fixing or after heat relaxation from the clip. The polyester film after heat fixation or after thermal relaxation is preferably cooled before being opened from the clip from the viewpoint of easily lowering the temperature of the clip when the polyester film is opened from the clip.

The cooling temperature of the polyester film after heat fixing or after heat relaxation is preferably 80 占 폚 or lower, more preferably 70 占 폚 or lower, and particularly preferably 60 占 폚 or lower.

As a method of cooling the polyester film after the heat fixation, specifically, a method of adding cold air to the polyester film can be mentioned.

As the temperature control means for heating or cooling the polyester film in the preheating, stretching, heat fixing, thermal relaxation, and cooling in the present embodiment, hot air or cold air may be added to the polyester film, And the ester film is brought into contact with the surface of a metal plate capable of temperature control or passed near the metal plate.

&Lt; Opening of film from clip >

After this process, the polyester film is opened from the clip.

It is preferable to control the surface temperature of the polyester film when the polyester film is detached from the clip in a range of 40 to 140 캜. The surface temperature of the polyester film when the polyester film is detached from the clip is more preferably 50 ° C or more and 120 ° C or less, and more preferably 60 ° C or more and 100 ° C or less.

In the method for producing a polyester film according to the present embodiment, the thickness of the polyester film after completion of film formation (after the opening process from the clip) is 40 μm or more and 500 μm or less, more preferably 60 μm or more and 400 μm or less, Is more preferable. The reason why the thickness of the polyester film is preferably in the above range is the same as that of the polyester film according to the present embodiment.

&Lt; Film recovery, slit, and winding >

After the film is opened from the clip, the film is subjected to trimming, slitting, and knurling as required, and wound for recovery.

In the method for producing a polyester film according to the present embodiment, it is preferable that the film width after opening from the clip is 0.8 to 6 m from the viewpoint of effectively ensuring the width of the film product and from not oversizing the apparatus, , More preferably from 1 to 4 m. An optical film requiring precision is generally formed to have a thickness of less than 3 m, but in this embodiment, it is preferable to form the film with the same width.

In addition, the film having a wide width may preferably be slit after being slit to not less than 2 but not more than 6, more preferably not less than 2 but not more than 5, more preferably not more than 3 but not more than 4.

After the slit, both ends are knurled (knurled).

It is preferable that the winding is performed in a winding core of 70 mm or more and 600 mm or less in diameter of 1000 m or more and 10000 m or less. The winding tension per unit area of the film is preferably 3 to 30 kgf / cm ² , more preferably 5 to 25 kgf / cm ² , and still more preferably 7 to 20 kgf / cm ² . It is also preferable to bond the masking film before winding.

[Hard Coat Film]

The polyester film according to the present embodiment can be suitably used for a base coat film of a hard coat film.

That is, the hard coat film according to the present embodiment has the base film including the polyester film according to the above-described embodiment and the hard coat layer laminated on at least one side of the polyester film.

<Hard coat layer>

Hereinafter, the hard coat layer of the hard coat film according to the present embodiment will be described.

The hard coat layer may be formed by any one of a wet coating method and a dry coating method (vacuum film formation), but it is preferable that the hard coating layer is formed by a wet coating method having excellent productivity.

As the hard coat layer, for example, JP-A-2013-45045, JP-A-2013-43352, JP-A-2012-232459, JP-A-2012-128157, JP- 131409, JP-A-2011-131404, JP-A-2011-126162, JP-A-2011-75705, JP-A-2009-286981, JP-A-2009-263567, Japanese Patent Application Laid-Open Nos. 2009-75248, 2007-164206, 2006-96811, 2004-75970, 2002-156505, 2001-272503 A hard coat layer described in WO12 / 018087, WO12 / 098967, WO12 / 086659 and WO11 / 105594 may be used.

(Thickness of the hard coat layer)

The thickness of the hard coat layer of the hard coat film according to the present embodiment is preferably 5 占 퐉 or more. When the thickness of the hard coat layer is 5 탆 or more, a hard coat film having high scratch resistance can be obtained.

From this point of view, the thickness of the hard coat layer of the hard coat film according to the present embodiment is more preferably 10 占 퐉 or more, and more preferably 15 占 퐉 or more.

If the thickness of the hard coat layer is excessively large, the punching process tends to be difficult. Therefore, the thickness of the hard coat layer is preferably 40 占 퐉 or less, more preferably 35 占 퐉 or less.

(Constituent material of the hard coat layer)

The hard coat layer of the hard coat film according to the present embodiment,

At least the structure derived from a), the structure derived from b), the structure derived from c) and d)

The hard coat layer contains 15 to 70 mass% of the structure derived from the following a), 25 to 80 mass% of the structure derived from the following b), and 0.1 to 0.1 mass% of the following composition (c) in the case where the total solid content of the hard coat layer is 100 mass% By mass to 10% by mass, and d) from 0.1% by mass to 10% by mass.

a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and having a molecular weight of 300 or less

b) a compound having a group containing three or more ethylenically unsaturated double bonds in the molecule

c) a radical polymerization initiator

d) cationic polymerization initiator

By providing the hard coat layer having such a constitution, the hard coat film according to the present embodiment has a high pencil hardness and excellent smoothness, so that the change in the appearance of the film after the wet heat aging is suppressed.

In the present embodiment, it is preferable that the hard coat layer has a hard coat property. In the present specification, the hard coat property means a pencil hardness of 7H or more from the viewpoint of being used as a top surface protective film of an image display device as a glass substitute hard coat film. The hard coat layer preferably has a pencil hardness of 8H or more.

The hard coat film of this embodiment having such a structure is preferably manufactured by a hard coat film manufacturing method according to this embodiment described later.

<Configuration>

The hard coat film according to the present embodiment is preferably a structure in which a hard coat layer is provided on at least one surface of the polyester film according to the above embodiment. The hard coat film according to the present embodiment is formed by curing a composition for forming a hard coat layer comprising a), b), c) and d), wherein the composition for forming a hard coat layer It is preferable that the composition contains 15 to 70 mass% of a), 25 to 80 mass% of b), 0.1 to 10 mass% of c) and 0.1 to 10 mass% of d) when the total solids content of the composition is 100 mass% More preferable.

<Composition for forming hard coat layer and hard coat layer>

Hereinafter, details of each component included in the hard coat layer and the composition for forming a hard coat layer will be described.

[a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in a molecule and having a molecular weight of 300 or less]

The hard coat film according to the present embodiment contains 15 to 70% by mass of the structure derived from the following a) when the total solid content of the hard coat layer is 100% by mass.

a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in a molecule and having a molecular weight of 300 or less.

Also, the hard coat layer is formed by curing a composition for forming a hard coat layer containing at least a), b), c) and d), and the composition for forming a hard coat layer is formed as a whole When the solid content is 100% by mass, the content of a) is preferably 15 to 70% by mass.

A) a compound having a molecular weight of not more than 300 and having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and contained in the composition for forming a hard coat layer will be described. a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and having a molecular weight of 300 or less is also referred to as "a) component ".

Examples of the group containing an ethylenically unsaturated double bond include polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group and an allyl group, and among these, a (meth) acryloyl group and -C ) OCH = CH ₂ is preferable, and (meth) acryloyl group is particularly preferable. By having a group containing an ethylenically unsaturated double bond, high hardness can be maintained, and heat and humidity resistance can also be imparted.

The term "(meth) acryloyl group" as used in the present specification includes "acryloyl group" and "methacryloyl group", and "(meth) acrylate" Methacrylate ", and "(meth) acrylic" means " acrylic "and" methacrylic ".

In the present embodiment, the number of groups containing an epoxy group and an ethylenically unsaturated double bond in the molecule is one. When the number of each functional group is one, the number of functional groups (groups containing an epoxy group and an ethylenically unsaturated double bond) is decreased as compared with the case where two or more functional groups are present, thereby decreasing the molecular weight and increasing the pencil hardness.

The molecular weight of component (a) is 300 or less, preferably 210 or less, more preferably 200 or less.

When the molecular weight of the component (a) is 300 or less, the number of sites other than the group containing the epoxy group and the ethylenically unsaturated double bond is reduced, and the pencil hardness can be increased.

From the viewpoint of suppressing volatilization at the time of forming the hard coat layer, the molecular weight of the component (a) is preferably 100 or more, and more preferably 150 or more.

As the component (a), a compound having one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and having a molecular weight of 300 or less is not limited, but is preferably a compound represented by the following formula (7).

Equation (7)

(2)

In formula (7), R represents monocyclic hydrocarbon or bridged hydrocarbon, L represents a single bond or a divalent linking group, and Q represents a group containing an ethylenically unsaturated double bond.

When R in the formula (7) is a monocyclic hydrocarbon, it is preferably an alicyclic hydrocarbon, more preferably an alicyclic group having 4 to 10 carbon atoms, more preferably an alicyclic group having 5 to 7 carbon atoms, Alicyclic groups are particularly preferred. Specifically, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group and a cycloheptyl group are preferable, and a cyclohexyl group is particularly preferable.

When R in the formula (7) is a bridged hydrocarbon, bicyclic bridges (bicyclo rings) and tricyclic bridges (tricyclo rings) are preferable, and bridged hydrocarbons having 5 to 20 carbon atoms are exemplified, and a novolinyl group, , An isobornyl group, a tricyclodecenyl group, a dicyclopentenyl group, a dicyclopentanyl group, a tricyclopentenyl group, and a tricyclopentanyl group, an adamantyl group, and a lower alkyl group-substituted adamantyl group.

When L represents a divalent linking group, a divalent aliphatic hydrocarbon group is preferable. The divalent aliphatic hydrocarbon group preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 carbon atom. The bivalent aliphatic hydrocarbon group is preferably a straight chain, branched or cyclic alkylene group, more preferably a linear or branched alkylene group, and more preferably a straight chain alkylene group.

Examples of Q, (meth) there may be mentioned a polymerizable functional group such as acryloyl group, vinyl group, styrene group, an allyl group, among others, (meth) acrylic group and a -C (O) OCH = CH ₂ Preferably , And particularly preferably a (meth) acryloyl group.

The specific compound of the component (a) is not particularly limited as long as it has a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and has a molecular weight of 300 or less, and examples thereof include those described in JP-A 10-17614 A compound represented by the following formula (1A) or (1B), 1,2-epoxy-4-vinylcyclohexane, and the like can be used.

Among them, a compound represented by the following formula (1A) or (1B) is more preferable, and a compound represented by the following formula (1A) having a lower molecular weight is more preferable. The compound represented by the following formula (1A) and its isomer are also preferable. In formula (1A), L ₂ represents a divalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and the component having a carbon number of 1 (a) is epoxycyclohexylmethyl (meth) acrylate ) Is more preferable from the viewpoint of improving smoothness.

By using these compounds, high pencil hardness and excellent smoothness can be made compatible at a higher level.

(3)

In formula (1A), R ₁ represents a hydrogen atom or a methyl group, and L ₂ represents a divalent aliphatic hydrocarbon group having 1 to 6 carbon atoms.

[Chemical Formula 4]

In formula (1B), R ₁ represents a hydrogen atom or a methyl group, and L ₂ represents a divalent aliphatic hydrocarbon group having 1 to 6 carbon atoms.

The divalent aliphatic hydrocarbon group of L _{2 in} the formulas (1A) and (1B) preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and more preferably 1 carbon atom. The bivalent aliphatic hydrocarbon group is preferably a straight chain, branched or cyclic alkylene group, more preferably a linear or branched alkylene group, and more preferably a straight chain alkylene group.

The structure derived from a) is contained in an amount of 15 to 70 mass% when the total solid content of the hard coat layer is 100 mass%. The component a) is contained in an amount of 15 to 70 mass% when the total solid content of the composition for forming a hard coat layer in the present embodiment is 100 mass%. When the content of the structure derived from a) or the content of the component (a) in the composition for forming the hard coat layer or the hard coat layer is 15 mass% or more, the surface smoothness is sufficiently improved. On the other hand, when the content of the composition derived from a) or the content of the component (a) in a composition for forming a hard coat layer or a hard coat layer is 70% by mass or less, the surface hardness can be sufficiently increased.

The structure derived from a) is preferably contained in an amount of 18 to 50 mass%, more preferably 22 to 40 mass%, when the total solid content of the hard coat layer is 100 mass%. The component (a) is contained preferably in an amount of 18 to 50 mass%, more preferably in an amount of 22 to 40 mass%, more preferably in a range of 20 to 40 mass%, when the total solid content of the composition for forming a hard coat layer in the present embodiment is 100 mass% Do.

[b) a compound having a group containing at least three ethylenically unsaturated double bonds in the molecule]

The hard coat film according to the present embodiment contains 25 to 80% by mass of the structure derived from the following b) when the hard coat layer has a total solid content of 100% by mass of the hard coat layer.

b) a compound having a group containing at least three ethylenically unsaturated double bonds in the molecule.

Also, the hard coat layer is formed by curing a composition for forming a hard coat layer containing at least a), b), c) and d), and the composition for forming a hard coat layer is formed as a whole When the solid content is 100% by mass, it is preferable that b) is contained in an amount of 25 to 80% by mass.

A compound having a group containing three or more ethylenically unsaturated double bonds in a molecule contained in the composition for forming a hard coat layer in the present embodiment will be described. b) a compound having a group containing at least three ethylenically unsaturated double bonds in the molecule is also referred to as "b) component ".

The component (b) can exhibit high hardness by having a group containing three or more ethylenically unsaturated double bonds in the molecule.

The component (b) may have a group containing 3 or more and 20 or less ethylenically unsaturated double bonds in the molecule.

Examples of the component (b) include polyhydric alcohols and esters of (meth) acrylic acid, vinylbenzene and its derivatives, vinylsulfone, and (meth) acrylamide. Of these, compounds having three or more (meth) acryloyl groups are preferable from the viewpoint of hardness, and acrylate compounds that form cured products having a high hardness widely used in the industry can be mentioned. Such compounds include esters of polyhydric alcohols and (meth) acrylic acid, and compounds having groups containing three or more ethylenically unsaturated double bonds in the molecule. (Meth) acrylate, trimethylolpropane tri (meth) acrylate, EO-modified trimethylol propane lye (meth) acrylate, (di) pentaerythritol tetra (Meth) acrylate, trimethylolpropane tri (meth) acrylate, PO-modified trimethylol propane tri (meth) acrylate, EO modified phosphoric tri (meth) acrylate, trimethylol ethane tri (Meth) acrylate, pentaerythritol hexa (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta , 2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, polyester polyacrylate, caprolactone modified tris (acryloxyethyl ) Isocyanurate, tripentaerythritol triacrylate, tripentaerythritol hexatriacrylate, 1,2,4-cyclohexanetetra (meth) acrylate, and pentaglycerol triacrylate.

Further, a resin (oligomer or prepolymer) having three or more (meth) acryloyl groups, a polyfunctional (meth) acrylate having three or more (meth) acryloyl groups, and a urethane (meth) acrylate are also preferable .

Examples of the resin (oligomer or prepolymer) having three or more (meth) acryloyl groups include polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiro acetal resins, Oligomers or prepolymers of polyfunctional compounds such as polybutadiene resins, polythiadiene resins, polythiol polyene resins and polyhydric alcohols.

As specific examples of polyfunctional (meth) acrylates having three or more (meth) acryloyl groups, mention may be made of the exemplified compounds shown in Japanese Patent Laid-Open No. 2007-256844, paragraph 0096, and the like.

Specific examples of polyfunctional acrylate compounds having three or more (meth) acryloyl groups include KAYARAD DPHA, DPHA-2C, PET-30, TMPTA, TPA-320 and TPA-330 manufactured by Nippon Kayaku Co., , V # 400 and V # 36095D manufactured by Osaka Kiso Kagaku Kogyo Co., Ltd., and polyol such as DIPA-20, DPCA-30, DPCA-60, GPO- Methacrylic acid esters. UV-7000B, UV-7600B, UV-7600B, UV-7600B, UV-7630B, UV-7640B, UV-7600B, UV- UV-7510B, UV-7461TE, UV-3000B, UV-3200B, UV-3210EA, UV-3310EA, UV-3310B, UV-3500BA, UV- UV-2250EA, UV-2750B (manufactured by Nippon Gosei Kagaku), UL-503LN (manufactured by Kyoeisha Chemical Co., Ltd.), Unidick 17-806, 17-813, V AU-2010, AU-4, and EB-4000BA (manufactured by DIC Corporation), EB-1290K, EB-220, EB-5129, EB- 3-functionalities such as Aronix M-1960 (manufactured by Toagosei Co., Ltd.), ARTREX UN-3320HA, UN-3320HC, UN-3320HS, UN-904 and HDP- Or more of trifunctional or higher functional compounds such as Aronix M-8100, M-8030, M-9050 (manufactured by Doa Kosei KK) and KBM-8307 (manufactured by Daicel-Cotech) It can be suitably used.

The component (b) may be composed of a single compound or a combination of a plurality of compounds.

The structure derived from b) is contained in an amount of 25 to 80 mass% when the total solid content of the hard coat layer is 100 mass%.

Component (b) is contained in an amount of 25 to 80 mass% when the total solid content of the composition for forming a hard coat layer in the present embodiment is 100 mass%. When the content of the structure derived from b) or the content of the component b) is 25% by mass or more with respect to the composition for forming the hard coat layer or the hard coat layer, sufficient hardness can be obtained. On the other hand, when the content of the structure derived from b) or the content of the component b) in the composition for forming a hard coat layer or the hard coat layer is 80% by mass or less, the content of the a) Smoothness is sufficient.

The structure derived from b) is preferably contained in an amount of 40 to 75 mass%, and more preferably 60 to 75 mass%, when the total solid content of the hard coat layer is 100 mass%. The component b) is preferably contained in an amount of 40 to 75% by mass, more preferably 60 to 75% by mass, in the case where the total solid content of the composition for forming a hard coat layer in the present embodiment is 100% Do.

[Other curable compounds]

The composition for forming the hard coat layer may contain a curing compound other than the component (a) and the component (b) (hereinafter also referred to as "another curing compound"). As other curable compounds, various compounds having a polymerizable group that can be cured (polymerized) by a curing treatment can be used. Examples of the polymerizable group include a polymerizable group capable of undergoing a polymerization reaction by irradiation with light, an electron beam, or a radiation, and a polymerizable group capable of undergoing a polymerization reaction by heating, and a photopolymerizable group is preferred. Other curable compounds may be monomers, oligomers, prepolymers, and the like.

Specific examples of the polymerizable group include ring-opening polymerization type polymerizable groups such as epoxy groups such as polymerizable unsaturated groups such as (meth) acryloyl group, vinyl group, styryl group and allyl group. Among them, a (meth) acryloyl group is preferable from the viewpoint of curability and the like.

Specific examples of other curing compounds that may be contained in the composition for forming a hard coat layer include the following compounds.

(Meth) acrylic acid diesters of alkylene glycol such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate and propylene glycol di (meth) acrylate; (Meth) acrylate such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and polypropylene glycol di (Meth) acrylic acid diesters of alkylene glycol; (Meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate; Ethylene oxide or propylene oxide adducts such as 2,2-bis {4- (acryloxy diethoxy) phenyl} propane and 2,2-bis {4- (acryloxypolypropoxy) (Meth) acrylic acid diesters; Urethane (meth) acrylates; Polyester (meth) acrylates; Isocyanuric acid acrylates; Epoxy (meth) acrylates.

As the urethane (meth) acrylate, for example, an isocyanate is reacted with a hydroxyl group-containing compound such as an alcohol, a polyol, and / or a hydroxyl group-containing acrylate, (Meth) acrylate obtained by esterifying a polyurethane compound obtained by (meth) acrylic acid. As specific examples, various commercial products mentioned in paragraph 0017 of Japanese Patent Laid-Open No. 2007-256844 can be exemplified.

The composition for forming a hard coat layer may contain an epoxy compound having an epoxy group as a polymerizable group as another curable compound from the viewpoint of reduction in curing shrinkage. As the epoxy compound, a polyfunctional epoxy compound containing two or more epoxy groups in one molecule is preferable. Specific examples thereof include those disclosed in Japanese Patent Application Laid-Open Nos. 2004-264563, 2004-264564, 2005-37737, 2005-37738, 2005-140862, Epoxy compounds described in JP-A-2005-140862, JP-A-2005-140863, and JP-A-2002-322430. It is also preferable to use a compound having both an epoxy group such as glycidyl (meth) acrylate and an acrylic polymerizable group.

The content of the other curing compound relative to the total solid content of the composition for forming a hard coat layer is preferably not more than 15% by mass from the viewpoint of the hardness of the hard coat layer when the total solid content of the composition for forming a hard coat layer is 100% , More preferably not more than 10 mass%, more preferably not more than 1 mass%, even more preferably not more than 0.01 mass%, particularly preferably not substantially.

[c] Radical polymerization initiator]

The hard coat film according to the present embodiment contains 0.1 to 10% by mass of the radical polymerization initiator c) when the hard coat layer contains 100% by mass of the total solid content of the hard coat layer.

The radical polymerization initiator c) contained in the composition for forming a hard coat layer or a hard coat layer in the present embodiment will be described. Hereinafter, c) the radical polymerization initiator is also referred to as "c) component ".

The polymerization of the compound having an ethylenically unsaturated group can be carried out by irradiation with ionizing radiation or heating in the presence of a photo radical polymerization initiator or a thermal radical polymerization initiator.

As the photo- and thermal polymerization initiator, commercially available compounds can be used, and they can be used in combination with a commercially available compound such as those described in "Latest UV curing technology" (p. 159, published by Daikaus Gazihiro Publishing Co., It is listed in the catalog of Chiba Specialty Chemicals Co., Ltd.

Specific examples of the c) component include an alkylphenon-based photopolymerization initiator (Irgacure 651, Irgacure 184, DAROCURE 1173, Irgacure 2959, Irgacure 127, DAROCURE MBF, Irgacure 907, Irgacure 369, Irgacure 379EG), an acylphosphine oxide photopolymerization initiator (Irgacure 819, LUCIRIN TPO) (Irgacure784, Irgacure OXE01, Irgacure OXE02, and Irgacure754).

The amount of component (c) added is in the range of 0.1 to 10% by mass, preferably 1 to 5% by mass, based on 100% by mass of the total solid content of the composition for forming a hard coat layer or hard coat layer in this embodiment And more preferably 2 to 4% by mass. When the addition amount of the component (c) is 0.1% by mass or more when the total solid content of the composition for forming a hard coat layer or the hard coat layer is 100% by mass, the polymerization proceeds sufficiently and the pencil hardness of the hard coat layer can be increased . On the other hand, when the addition amount of the component (c) is 10% by mass or less when the total solid content of the composition for forming a hard coat layer or the hard coat layer is 100% by mass, the UV light reaches the inside of the film, . These c) radical initiators may be used alone, or a plurality of species may be used in combination.

[d) Cationic polymerization initiator]

The hard coat film according to the present embodiment contains 0.1 to 10% by mass of the cationic polymerization initiator when the hard coat layer contains 100% by mass of the total solid content of the hard coat layer.

The d) cationic polymerization initiator contained in the composition for forming a hard coat layer or a hard coat layer in the present embodiment will be described. Hereinafter, the d) cationic polymerization initiator is also referred to as "d) component ".

Examples of the component (d) include known compounds such as photoinitiators for photocationic polymerization, photo-coloring agents for colorants, photo-discoloring agents, and known acid generators used in micro-resists, and mixtures thereof.

Examples thereof include an onium compound, an organic halogen compound, and a disulfone compound. These specific examples of the organohalogen compounds and the disulfone compounds include the same compounds as those of the compounds generating the radicals.

Examples of the onium compound include a diazonium salt, an ammonium salt, an iminium salt, a phosphonium salt, an iodonium salt, a sulfonium salt, an onium salt and a selenonium salt, and examples thereof include those described in Japanese Patent Application Laid-Open No. 2002-29162 0058] to [0059], and the like.

Examples of the cationic polymerization initiator particularly suitably used in the present embodiment include an onium salt, and a diazonium salt, an iodonium salt, a sulfonium salt, and an iminium salt may be used in combination with the photopolymerization initiator . Of these, the iodonium salt is most preferable from the viewpoint of light resistance.

Specific examples of onium salts which can be suitably used in the present embodiment include, for example, amylated sulfonium salts described in paragraph [0035] of Japanese Patent Application Laid-Open No. 9-268205, short-circuiting of Japanese Unexamined Patent Application Publication No. 2000-71366 Diaryliodonium salts or triarylsulfonium salts described in Nos. [0010] to [0011], sulfonium salts of thiobenzoic acid S-phenyl ester described in paragraph [0017] of Japanese Patent Application Laid-Open No. 2001-288205, And the onium salts described in paragraphs [0030] to [0033] of JP-A No. 2001-133696.

Other examples include organometallic / organic halides described in paragraphs [0059] to [0062] of JP-A No. 2002-29162, photoacid generators having o-nitrobenzyl type protecting groups, photodegradation to generate sulfonic acid (Iminosulfonate etc.) and the like.

Specific examples of the cationic polymerization initiator of the iodonium salt base include B2380 (Tokyo Kasei Kogyo), BBI-102 (Midori Kagaku), WPI-113 (Wako Pure Chemical Industries), WPI-124 (Wako Pure Chemical Industries) , WPI-169 (manufactured by Wako Pure Chemical Industries, Ltd.), WPI-170 (manufactured by Wako Pure Chemical Industries, Ltd.) and DTBPI-PFBS (manufactured by Toyo Gosei Chemical Co., Ltd.).

Furthermore, preferred examples of the cationic polymerization initiator based on iodonium salt include the following compounds FK-1 and FK-2.

Gwangyang ion polymerization initiator (Iodonium salt compound) FK-1

[Chemical Formula 5]

Gwangyang ion polymerization initiator (Iodonium salt compound) FK-2

[Chemical Formula 6]

As the d) component, only one kind may be used, or two or more kinds may be used in combination.

The component d) is added in the range of 0.1 to 10 mass%, preferably 0.5 to 3.0 mass%, when the total solid content of the composition for forming a hard coat layer or the hard coat layer in the present embodiment is 100 mass% By mass%. The addition amount is preferably in the above range because of stability of the coating liquid and polymerization reactivity.

[e) an inorganic particle having reactivity with a group containing an epoxy group or an ethylenically unsaturated double bond]

The composition for forming the hard coat layer or the hard coat layer in the present embodiment preferably contains e) inorganic particles having reactivity with a group containing an epoxy group or an ethylenically unsaturated double bond. Hereinafter, e) the inorganic particles having the reactivity of the group containing an epoxy group or an ethylenically unsaturated double bond is also referred to as "e) component ".

By adding the inorganic particles, the amount of curing shrinkage of the hard coat layer (cured layer) can be reduced, so that the smoothness can be improved. Further, it is possible to improve the pencil hardness by using inorganic particles having reactivity with groups containing an epoxy group or an ethylenically unsaturated double bond.

Examples of the inorganic particles include silica particles, titanium dioxide particles, zirconium oxide particles, aluminum oxide particles and the like. Among them, it is preferable that the inorganic particles having the reactivity of e) groups having an epoxy group or an ethylenically unsaturated double bond are silica particles.

In general, since the affinity of an inorganic particle with an organic component such as a polyfunctional vinyl monomer is low, an agglomerate is formed only by mixing only, or the hard coat layer after curing tends to be easily cracked. Therefore, in the component (e), it is preferable to treat the surface of the inorganic particle with a surface modifier containing an organic segment in order to increase the affinity between the inorganic particle and the organic component.

The surface modifier is preferably a surface modifier having a functional group capable of forming a bond with the inorganic particle or adsorbing to the inorganic particle and a functional group having high affinity with the organic component in the same molecule. As the surface modifier having a functional group capable of binding or adsorbing to the inorganic particles, a surface modifier such as a metal alkoxide surface modifier such as silane, aluminum, titanium or zirconium or a surface modifier such as a surface having an anionic group such as a phosphoric acid group, Modifiers are preferred. The functional group having a high affinity with an organic component may be a functional group that is only a combination of an organic component and a hydrophilic group, but is preferably a functional group capable of chemically bonding with an organic component. Particularly, a group containing an ethylenically unsaturated double bond , Or a ring-opening polymerizable group is preferable.

The surface modifier of the inorganic particles preferred in the present embodiment is a curable resin having a group containing a metal alkoxide or an anionic group and an ethylenically unsaturated double bond or a ring-opening polymerizable group in the same molecule. By chemically bonding to the organic component, the crosslinking density of the hard coat layer increases, and the pencil hardness can be increased.

Representative examples of these surface modifiers include the following unsaturated double bond-containing coupling agents, phosphoric acid group-containing organic curing resins, organic curing resins containing a sulfuric group, and organic curing resins containing carboxylic acid groups.

_{S-1 H 2 C = C} (X) COOC 3 H 6 Si (OCH 3) 3

S-2 H ₂ C = C (X) COOC ₂ H ₄ OTi (OC ₂ H ₅ ) ₃

S-3 H ₂ C = C (X) COOC ₂ H ₄ OCOC ₅ H ₁₀ OPO (OH) ₂

_{S-4 (H 2 C =} C (X) COOC 2 H 4 OCOC 5 H 10 O) 2 POOH

S-5 H ₂ C = C (X) COOC ₂ H ₄ OSO ₃ H

S-6 H ₂ C = C (X) COO (C ₅ H ₁₀ COO) ₂ H

S-7 H ₂ C = C (X) COOC ₅ H ₁₀ COOH

S-8 CH ₂ CH (O) CH ₂ OC ₃ H ₆ Si (OCH ₃ ) ₃

(X represents a hydrogen atom or CH ₃ )

The surface modification of these inorganic particles is preferably carried out in a solution. When the inorganic particles are mechanically and finely dispersed, a surface modifier is present together, or after the inorganic particles are finely dispersed, a surface modifier is added and stirred, or further surface modification is carried out before the inorganic particles are finely dispersed If necessary, heating, drying, heating, or pH change), followed by finely dispersing. As the solution for dissolving the surface modifier, an organic solvent having a high polarity is preferable. Specific examples thereof include known solvents such as alcohols, ketones and esters.

When the total solid content of the composition for forming a hard coat layer or the hard coat layer in the present embodiment is 100 mass%, the addition amount of the component (e) is preferably 5 to 40 mass% %, More preferably from 10 to 30 mass%.

The size (average primary particle size) of the inorganic particles is preferably from 10 nm to 100 nm, more preferably from 10 to 60 nm. The average particle diameter of the particles can be obtained from an electron microscope photograph. When the particle diameter of the inorganic particles is not less than the lower limit value, the effect of improving the hardness is obtained, and when it is not more than the upper limit value, the rise in haze can be suppressed.

The shape of the inorganic particles is not limited to spherical and non-spherical shapes, but is preferably an irregular shape in which 2 to 10 inorganic particles are connected, from the viewpoint of imparting hardness. It is presumed that a hardened particle network structure is formed by using inorganic particles in which several chains are connected in the form of chains to improve the hardness.

Specific examples of the inorganic particles include ELECOM V-8802 (spherical silica particles having an average primary particle diameter of 12 nm, manufactured by Nikkiso Co., Ltd.), ELECOM V-8803 (modified silica particles made by NIKKI Corporation), MiBK-SD MEK-AC-2140Z (spherical silica particles having an average primary particle diameter of 10 to 20 nm, manufactured by Nissan Kagaku Kogyo Co., Ltd.), MEK- (Spherical silica particles having an average primary particle size of 40 to 50 nm, manufactured by Nissan Kagaku Kogyo Co., Ltd.) and MiBK-SD-L (spherical silica particles having an average primary particle size of 40 to 50 nm, manufactured by Nissan Kagaku Kogyo Co., Silica particles) and MEK-AC-5140Z (spherical silica particles having an average primary particle diameter of 70 to 100 nm, manufactured by Nissan Chemical Industries, Ltd.). Among them, the release type ELECOM V-8803 is preferable from the viewpoint of imparting surface hardness.

[f) Polyester Yuretain]

The composition for forming a hard coat layer or a hard coat layer in the present embodiment is preferably f) containing a polyester urethane in view of increasing the embrittlement. Hereinafter, f) polyester ester is also referred to as "f) component ".

The polyester ester is a polymer containing an ester bond and a urethane bond (-O-CO-NH-) in a molecule.

f) The polyester urethane is preferably a polyester urethane having a tensile strength of 25 MPa or more and a tensile elongation of 200% or more. It is considered that the polyester urethane having a tensile strength of 25 MPa or more and a tensile elongation of 200% or more can contribute to the hardening of the hard coat layer and the imparting of appropriate flexibility. This is presumed to contribute to hardening of the hard coat layer and improvement of the brittleness.

When the content of polyester ester is 1 part by mass or more based on 100 parts by mass of the total solid content of the composition for forming a hard coat layer or hard coat layer, it is possible to sufficiently obtain the above effect by the addition of polyester urethane, If it is 10 parts by mass or less, the hardness of the cured layer can be maintained. Therefore, the content of polyester ester relative to 100 parts by mass of the total solid content of the composition for forming a hard coat layer or a hard coat layer is in the range of 1 to 10 parts by mass. More preferably 2 parts by mass or more from the viewpoints of improvement in brittleness and suppression of transparency, and more preferably 8 parts by mass or less from the viewpoint of maintaining the hardness of the hard coat layer.

Use of a polyester urethane showing the above tensile strength and tensile elongation as a polyester urethane contributes to achieving both hardening and improvement in brittleness by imparting appropriate flexibility to the hard coat layer. More preferably, the tensile strength is 40 MPa or more, and more preferably 50 MPa or more. The tensile strength is preferably 70 MPa or less from the viewpoint of the compatibility stability in the composition for forming a hard coat layer. On the other hand, the tensile elongation is preferably 450% or more, and more preferably 600% or more. From the viewpoint of securing the pencil hardness, which is one of the indexes of film hardness, the tensile elongation is preferably 1000% or less. The method of measuring pencil hardness will be described later in detail. The tensile strength and tensile elongation of the polyester urethane are determined to values measured using a tensile strength tester in accordance with JIS K 6251.

The polyester urethane may be obtained by polymerization of a monomer component comprising at least a diol, a dicarboxylic acid, and a diisocyanate. As these three types of monomers, a polyester having a hydroxyl group (-OH), a carboxyl group (-COOH), and an isocyanate group (-NCO) at both terminals of a hydrocarbon group having a non- branched structure Yuretene is preferred.

The hydrocarbon group having a non-branched structure is preferably an alkylene group, an alkenylene group, an alkenylene group, an arylene group or a combination thereof.

The alkylene group, alkenylene group and alkenylene group are preferably linear.

When the hydrocarbon group is an alkylene group, an alkenylene group or an alkynylene group, the number of carbon atoms is preferably 1 to 8, more preferably 2 to 6, and even more preferably 2 to 4.

The arylene group may have an alkyl group having 1 to 8 carbon atoms as a substituent.

The arylene group is preferably a phenylene group or a naphthylene group, more preferably a phenylene group, and more preferably a p-phenylene group.

The hydrocarbon group is preferably an alkylene group, an arylene group, or a combination thereof.

Examples of the diol used as the monomer of the polyester urethane include ethylene glycol, 1,3-propanediol, 1,4-butanediol, neopentylglycol, 1,6-hexanediol , 1,4-cyclohexane dimethanol and 1,5-pentanediol are preferred.

As the dicarboxylic acid, terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, succinic acid, glutaric acid, adipic acid, oxalic acid and malonic acid are preferable.

Examples of the diisocyanate include ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, m-xylylene diisocyanate, p- Phenylene diisocyanate, tolylene diisocyanate, p, p'-diphenylmethane diisocyanate and 1,5-naphthylene diisocyanate are preferable.

The number average molecular weight (Mn) of the polyester urethane is preferably 5000 or more, more preferably 10,000 or more from the viewpoint of affinity with the inorganic particles, and is preferably 50,000 or less from the viewpoint of compatibility with the curing compound.

Further, in one embodiment, the polyester urethane may have a reactive group. The reactive group is preferably a polymerizable unsaturated group. As specific examples, the functional groups that the inorganic particles may have are described first.

As the polyester ester described above, a polyester ester synthesized by a known method may be used, or a commercially available product may be used. Examples of commercially available products include Vylon (registered trademark) series (trade name) manufactured by Toyobo Co., Ltd. and Vylon UR-2300, Vylon UR-3200, Vylon UR-3210, Vylon UR- VYLON UR-8300, VYLON UR-8700, and the like can be preferably used.

[g) Antifouling agent]

The composition for forming a hard coat layer or a hard coat layer in the present embodiment is preferably such that g) an antifouling agent is contained because adhesion of fingerprints and fouling is reduced and the adhered fouling can be easily wiped off. It is also preferable from the viewpoint of improving the scratch resistance by improving the slidability of the surface. Hereinafter, g) the antifouling agent is also referred to as "g) component ".

The hard coat film according to the present embodiment comprises: (g) an antifouling agent-containing fluorine compound, wherein the fluorine-containing compound has a perfluoropolyether group and a polymerizable unsaturated group, and further contains a polymerizable unsaturated group in a molecule .

G) antifouling agent usable in the present embodiment will be described.

[Fluorocarbon compound having a polymerizable unsaturated group]

g) a compound having a perfluoropolyether group and a polymerizable unsaturated group and having a plurality of polymerizable unsaturated groups in one molecule (hereinafter referred to as "fluorinated antifouling agent ") containing an antifouling agent and a fluorinated compound, ") Is described.

The fluorinated antifouling agent is preferably a fluorinated compound having a structure represented by the following formula (F).

(F): (Rf) - [(W) - (R _A ) _n ] _m

In the formulas, Rf represents a (per) fluoroalkyl group or a (per) fluoropolyether group, W represents a linking group, and R _A represents a polymerizable unsaturated group. and n represents an integer of 1 to 3. m represents an integer of 1 to 3;

It is considered that the fluorine antifouling agent has the following effects (1) to (3) by having a polymerizable unsaturated group.

(1) compatibility with a compound having solubility to an organic solvent or an unsaturated double bond is enhanced, it is considered that the antifouling agent can be uniformly localized on the surface without forming an aggregate. In addition, it is possible to prevent the occurrence of defects due to aggregates.

(2) Even when the fluorine-containing antifouling agent is localized on the surface, the fluorine-containing antifouling agent or the compound having an unsaturated double bond can form a covalent bond by the photopolymerization reaction, so that the antifouling agent is peeled off due to abrasion, Deterioration of the antifouling property can be prevented.

(3) It is possible to prevent the loss of antifouling property and deterioration of the appearance caused by the precipitation of the antifouling agent by bleeding out.

In formula (F), R _A represents a polymerizable unsaturated group. The polymerizable unsaturated group is not particularly limited as long as it is a group capable of causing a radical polymerization reaction by irradiating active energy rays such as ultraviolet rays or electron rays and includes a (meth) acryloyl group, a (meth) acryloyloxy group, a vinyl group, (Meth) acryloyl group, a (meth) acryloyloxy group, and a group in which any hydrogen atom in these groups is substituted with a fluorine atom is preferably used.

As specific examples of the polymerizable unsaturated group, a group having a structure shown below is preferable.

(7)

In the formula (F), Rf represents a (per) fluoroalkyl group or a (per) fluoropolyether group.

Here, the (per) fluoroalkyl group represents at least one of a fluoroalkyl group and a perfluoroalkyl group, and the (per) fluoropolyether group is at least one of a fluoropolyether group and a perfluoropolyether group . From the viewpoint of antifouling property, the fluorine content in Rf is preferably high.

The (per) fluoroalkyl group is preferably a group of 1 to 20 carbon atoms, more preferably a group of 1 to 10 carbon atoms.

(Per) fluoroalkyl group is, for a straight-chain (for example, _{-CF 2 CF 3, -CH 2 (} CF 2) 4 H, -CH 2 (CF 2) 8 CF 3, -CH 2 CH 2 (CF 2) 4 H is even, and so on), a branch structure (e. g. _{CH (CF 3) 2, CH} 2 CF (CF 3) 2, CH (CH 3) CF 2 CF 3, CH (CH 3) (CF 2) 5 CF 2 H Etc.), and may be an alicyclic structure (preferably, a 5-membered ring or a 6-membered ring, for example, a perfluorocyclohexyl group, a perfluorocyclopentyl group, or an alkyl group substituted with them).

The (per) fluoropolyether group indicates the case where the (per) fluoroalkyl group has an ether bond, and may be monovalent or a divalent or higher. Examples of the fluoropolyether group include -CH ₂ OCH ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, -CH ₂ CH ₂ OCH ₂ CH ₂ C ₈ F ₁₇ , -CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H, fluorocycloalkyl groups having 4 to 20 carbon atoms and 4 to 20 carbon atoms, and the like. In addition, examples of a perfluoroalkyl polyether ether group, such as _{- (CF 2 O) p -} (CF 2 CF 2 O) q -, - [CF (CF 3) CF 2 O] p - [CF 2 (CF 3 -] -, - (CF ₂ CF ₂ CF ₂ O) _p -, - (CF ₂ CF ₂ O) _p -.

The total sum of p and q is preferably 1 to 83, more preferably 1 to 43, and most preferably 5 to 23.

It is particularly preferable that the fluorinated antifouling agent has a perfluoropolyether group represented by - (CF ₂ O) _p - (CF ₂ CF ₂ O) _q - from the viewpoint of excellent antifouling property.

P and q each independently represent an integer of 0 to 20; However, p + q is an integer of 1 or more.

From the viewpoint that the effects shown in the above-mentioned (1) to (3) are more remarkably obtained, it is preferable that the fluororesin stainproofing agent has a perfluoropolyether group and a plurality of polymerizable unsaturated groups in one molecule.

In the formula (F), W represents a linking group. W is, for example, an alkylene group, an arylene group, a heteroalkylene group, or a linking group combining these groups. These linking groups may further have an oxy group, a carbonyl group, a carbonyloxy group, a carbonylimino group, a sulfonamido group, or the like, or a functional group combining these.

W is preferably an ethylene group, more preferably an ethylene group bonded to a carbonyl imino group.

From the viewpoint that the effects shown in the above-mentioned (1) to (3) are more remarkably obtained, in the formula (F), the product (n x m) of n and m is preferably 2 or more, Do.

Examples of the preferred embodiments below include the following formulas (F-1) to (F-3), when n and m are both 1 in the formula (F).

Formula (F-1):

Rf ² (CF ₂ CF ₂ ) _p R ' ² CH ₂ CH ₂ R ² OCOCR ¹ = CH ₂

In formula (F-1), Rf ² represents any one of a fluorine atom or a fluoroalkyl group having 1 to 10 carbon atoms, R ¹ represents a hydrogen atom or a methyl group, R ² represents a single bond or an alkylene group , R ' ² represents a single bond or a divalent linking group, p is an integer representing the degree of polymerization, and the degree of polymerization p is not less than k (k is an integer not less than 3).

When R ' ² represents a divalent linking group, the divalent linking group may be the same linking group as W.

Examples of the fluoromonomer-containing telomeric acrylate in the formula (F-1) include a (meth) acrylic acid moiety or a completely fluorinated alkyl ester derivative.

Specific examples of the compound represented by the formula (F-1) are shown below, but the present invention is not limited to these compounds.

[Chemical Formula 8]

The compound represented by the above formula (F-1) can be obtained by subjecting the compound represented by the formula (F-1) to a group Rf ² (CF _{2 ^{CF 2) p R '2 CH}} 2 CH there is a case where a plurality of the fluorinated (meth) acrylic acid ester such as ₂ R ² p O-, each k, k + 1, k + 2, ··· in.

Formula (F-2):

F (CF ₂ ) _q -CH ₂ -CHX-CH ₂ Y

In Formula (F-2), q is an integer of 1 to 20, and X and Y are each independently any one of a (meth) acryloyloxy group and a hydroxyl group, and at least one of them is a (meth) acryloyloxy group.

The fluorine (meth) acrylic acid ester represented by the formula (F-2) has a fluoroalkyl group having 1 to 20 carbon atoms and having a trifluoromethyl group (CF ₃ -) at the terminal, and the fluorine (meth) Lt; RTI ID = 0.0 &gt; trifluoromethyl &lt; / RTI &gt; group is effectively oriented on the surface.

In terms of antifouling property and ease of production, q is preferably from 6 to 20, more preferably from 8 to 10. The fluorinated (meth) acrylic acid ester having a fluoroalkyl group having 8 to 10 carbon atoms is excellent in water repellency and oil repellency even when compared with a fluorinated (meth) acrylic acid ester having fluoroalkyl groups having other chains, So that the antifouling property is excellent.

Specific examples of the fluorine (meth) acrylate esters represented by the formula (F-2) include 1- (meth) acryloyloxy-2-hydroxy-4,4,5,5,6,6,7,7 , 8,8,9,9,10,10,11,11,12,12,13,13,13-henecosafluorotridecane, 2- (meth) acryloyloxy-1-hydroxy 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,13-Hexecosulfurotridide Cyan and 1,2-bis (meth) acryloyloxy-4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12 , 13,13,13-hexenecafluorotridecane, and the like. In the present embodiment, it is preferable that 1-acryloyloxy-2-hydroxy-4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11, 12,12,13,13,13-heneicosafluorotridecane is preferred.

Formula (F-3):

F (CF ₂ ) _r O (CF ₂ CF ₂ O) _s CF ₂ CH ₂ OCOCR ³ = CH ₂

In the formula (F-3), R ³ is a hydrogen atom or a methyl group, s is an integer of 1 to 20, and r is an integer of 1 to 4.

The fluorine atom-containing monofunctional (meth) acrylate represented by the above formula (F-3) can be obtained by reacting a fluorine atom-containing alcohol compound represented by the following formula (FG-3) with a (meth) acrylic acid halide.

Formula (FG-3):

_{F (CF 2) r O (} CF 2 CF 2 O) s CF 2 CH 2 OH

In the formula (FG-3), s represents an integer of 1 to 20, and r represents an integer of 1 to 4.

Specific examples of the fluorine atom-containing alcohol compound represented by the formula (FG-3) include 1H, 1H-perfluoro-3,6-dioxaheptan-1-ol, 1H, 1H-perfluoro-3,6-dioxadecan-1-ol, 1H, 1H-perfluoro-3,6,9-trioxadecane- 1H, 1H, 1H-perfluoro-3,6,9-trioxandecan-1-ol, 1H, 1H- perfluoro-3,6,9-trioxatridecan- Perfluoro-3,6,9,12-tetraoxatetradecan-1-ol, 1H, 1H-perfluoro-3,6,9,12-tetraoxatetradecan- Perfluoro-3,6,9,12-tetraoxahexadecan-1-ol, 1H, 1H-perfluoro-3,6,9,12,15-pentaoxahexadecan- 1H, 1H-perfluoro-3,6,9,12,15-pentaoxaheptadecan-1-ol, 1H, 1H- perfluoro-3,6,9,12,15-pentaoxanonadecane- 1-ol, 1H, 1H-perfluoro-3,6,9,12,15,18-hexaoxiacoate-1-ol, 1H, 1H-perfluoro-3,6,9,12,15 , 18-hexaoxodoic acid-1-ol, 1H, 1H-perfluoro Heptaoxatricoan-1-ol, 1H, 1H-perfluoro-3,6,9,12,15,18,21-heptaoxapenta Kosan-1-ol and the like.

Specific examples thereof include 1H, 1H-perfluoro-3,6-dioxaheptan-1-ol (trade name: C5GOL, manufactured by EXFOUR), 1H, 1H-purple Perfluoro-3,6-dioxadecan-1-ol (trade name "C8GOL" Perfluoro-3,6,9-trioxatridecan-1-ol (trade name "C10GOL ", manufactured by EXFOUR), 1H, 6,9,12-tetraoxahexadecan-1-ol (trade name "C12GOL ", manufactured by EXFOUR).

In the present embodiment, 1H, 1H-perfluoro-3,6,9,12-tetraoxatridecan-1-ol is preferably used.

Examples of the (meth) acrylic acid halide to be reacted with the fluorine atom-containing alcohol compound represented by the formula (FG-3) include (meth) acrylic acid fluoride, (meth) acrylic acid chloride, (meth) acrylic acid bromide, Id can be said. From the viewpoint of availability and the like, (meth) acrylic acid chloride is preferable.

Specific preferred examples of the compound represented by the formula (F-3) are shown below, but are not limited thereto. A preferable specific example represented by the formula (F-3) is described in Japanese Patent Application Laid-Open No. 2007-264221.

(b-1): F ₉ C ₄ OC ₂ F ₄ OC ₂ F ₄ OCF ₂ CH ₂ OCOCH = CH ₂

(b-2): F ₉ C ₄ OC ₂ F ₄ OC ₂ F ₄ OCF ₂ CH ₂ OCOC (CH ₃ ) = CH ₂

Further, in addition to the compound represented by the formula (F-3), a compound represented by the following formula (F-3A) can be preferably used.

Formula (F-3A):

Rf ³ - [(O) _c (O = C) _b (CX ⁴ X ⁵ ) _a -CX ³ = CX ¹ X ² ]

Wherein X ¹ and X ² each independently represent H or F, X ³ represents H, F, CH ₃ or CF ₃ , X ⁴ and X ⁵ each independently represent H, F, or a represents a CF _3, a, b, and c are each independently 0 or 1, Rf ³ represents a fluorine-containing alkyl group containing an ether bond with a carbon number of 18 ~ 200), the Rf group ^3,

Formula (FG-3A):

^{_{- (CX 6 2 CF 2 CF}} 2 O) -

(Wherein X &lt; ⁶ &gt; is F or H).

Examples of the fluorinated polyether compound represented by the formula (F-3A)

(O) (C-1) Rf ³ - [(O) (O = C) _b -CX ³ = CX ¹ X ² ]

^{(c-2) Rf 3 -} [(O) (O = C) -CX 3 = CX 1 X 2]

^{(c-3) Rf 3 -} [(O) c (O = C) -CF = CH 2]

, And the polymerizable unsaturated group of the fluorinated polyether compound is preferably a group having the following structure. The definition of each symbol in (c-1) to (c-3) agrees with the formula (F-3A).

[Chemical Formula 9]

The fluorinated polyether compound represented by the formula (F-3A) may have a plurality of polymerizable unsaturated groups,

[Chemical formula 10]

And the like. In the present embodiment, a compound having a structure of -O (C = O) CF = CH ₂ is preferable because a polymerization (curing) reactivity is particularly high and a cured product can be efficiently obtained.

Formula Rf ³ groups according also to the emitter compound in fluoride poly represented by (F-3A) formula (FG-3A) also important to include the six or more Rf ³ to teoswae the fluorine polyester repeat units and, accordingly, the Antifouling properties can be imparted.

More specifically, it may be a mixture containing a compound having 6 or more repeating units of a fluorinated polyether chain. When used in the form of a mixture, a fluorinated unsaturated compound having less than 6 repeating units and 6 or more fluorinated In the distribution of the unsaturated compound, it is preferable that the mixture contains the fluorinated unsaturated compound having the highest proportion of the polyfunctional unsaturated compound having 6 or more repeating units of the polyether chain.

The repeating unit of the fluorinated polyether chain of the formula (FG-3A) is preferably at least 6, more preferably at least 10, more preferably at least 18, and particularly preferably at least 20 repeating units. As a result, not only water repellency but also removability against contamination including antifouling, especially oil component, can be improved. In addition, gas permeability can be more effectively imparted. The fluorinated polyether chain may be present at the terminal of the Rf ³ group or may be present in the middle of the chain.

Specifically, the Rf ³ group is, for example,

Formula (c-4):

R ⁴ - (CX ⁶ ₂ CF ₂ CF ₂ O) _t - (R ⁵ ) _e -

Wherein X ⁶ is the same as in formula (FG-3A), R ⁴ is selected from a hydrogen atom, a halogen atom or an alkyl group, a fluorine alkyl group, an alkyl group containing an ether bond and a fluorine alkyl group containing an ether bond , R ⁵ is a divalent or higher-valent organic group, t is an integer of 6 to 66, and e is 0 or 1).

That is, it is a fluorinated organic compound having a reactive carbon-carbon double bond and further having R ⁴ at the terminal through a divalent or higher-valent organic group R ⁵ .

R ⁵ may be any organic group as long as it is an organic group capable of bonding a fluorinated polyether chain of formula (FG-3A) to a reactive carbon-carbon double bond. For example, an alkylene group, a fluorinated alkylene group, an alkylene group containing an ether bond, and a fluorinated alkylene group containing an ether bond. Among them, a fluorinated alkylene group containing a fluorinated alkylene group or an ether bond is preferable in terms of transparency and low refractive index.

As a specific example of the fluorinated polyether compound represented by the formula (F-3A), a compound exemplified in WO2003 / 022906 pamphlet is preferably used. In the present embodiment, CH ₂ ═CF-COO-CH ₂ CF ₂ CF ₂ - (OCF ₂ CF ₂ CF ₂ ) ₇ -OC ₃ F ₇ can be particularly preferably used.

When n and m are not 1 at the same time in the formula (F), the following formulas (F-4) and (F-5) are preferred.

(F-4): (Rf ¹ ) - [(W) - (R _A ) _n ] _m

(Formula (F-4) of, Rf ¹ is a (per) ether group in poly alkyl group or a (per) fluoro-fluorophenyl, W is a linkage group, R _A represents a functional group having an unsaturated double bond. N is 1-3, m represents an integer of 1 to 3, and n and m are not simultaneously 1.)

It is preferable that n is 2 to 3 and m is 1 to 3, n is 2 to 3 and m is 2 to 3 from the viewpoint of excellent water repellency and oil repellency as well as excellent water and oil repellency (antifouling durability) And most preferably n is 3 and m is 2 to 3.

Rf ¹ may be a monovalent to trivalent group. Rf when ¹ is 1 Cain, as the terminal group _{(C n F 2n + 1)} -, (C n F 2n + 1 O) -, (XC n F 2n O) -, (XC n F 2n + 1) - ( X is hydrogen, chlorine, or bromine, and n is an integer of 1 to 10). Specific examples thereof include CF ₃ O (C ₂ F ₄ O) _p CF ₂ -, C ₃ F ₇ O (CF ₂ CF ₂ CF ₂ O) _p CF ₂ CF ₂ -, C ₃ F ₇ O (CF (CF ₃ ) CF ₂ O) _p CF (CF ₃ ) -, and F (CF (CF ₃ ) CF ₂ O) _p CF (CF ₃ ) -.

Here, the average value of p is 0 to 50. Preferably 3 to 30, more preferably 3 to 20, and most preferably 4 to 15.

If Rf ¹ is divalent _{is, - (CF 2 O) q} (C 2 F 4 O) r CF 2 -, - (CF 2) 3 O (C 4 F 8 O) r (CF 2) 3 -, - CF ₂ O (C ₂ F ₄ O) _r CF ₂ -, -C ₂ F ₄ O (C ₃ F ₆ O) _r C ₂ F ₄ -, -CF (CF ₃ ) (OCF ₂ CF (CF ₃ ) _{s OC t F 2t O (CF} (CF 3) CF 2 O) r CF (CF 3) - and the like can be preferably used.

Here, the average value of q, r, s in the equation is 0 to 50. Preferably 3 to 30, more preferably 3 to 20, and most preferably 4 to 15. t is an integer of 2 to 6;

Preferred embodiments of the compounds represented by formula (F-4) or methods for their synthesis are described in International Publication No. 2005/113690.

_{Hereinafter, F (CF (CF 3)} CF 2 O) p CF (CF 3) - to the average value of p 6 ~ 7 The compound described as "HFPO-", and in _{- (CF (CF 3) CF} 2 O-) _p CF (CF ₃ ) -, the compound in which the average value of p is 6 to 7 is referred to as "-HFPO-", and the specific compound of formula (F-4) is shown.

(d-1): HFPO-CONH-C- (CH ₂ OCOCH = CH ₂ ) ₂ CH ₂ CH ₃

(d-2): HFPO- CONH-C- (CH 2 OCOCH = CH 2) 2 H

(d-3): HFPO- CONH-C 3 H ₆ NHCH _3, and 1: 1 Michael addition polymer of trimethylolpropane triacrylate

(d-4): ???????? (CH ₂ ═CHCOOCH ₂ ) ₂ HC-CONH-HFPO-CONH-C- (CH ₂ OCOOCH═CH ₂ ) ₂ H

(d-5): ???????? (CH ₂ ═CHCOOCH ₂ ) ₃ -C-CONH-HFPO-CONH-C- (CH ₂ OCOCH═CH ₂ ) ₃

Further, a compound represented by the following formula (F-5) may be used as the compound represented by the formula (F-4).

Formula (F-5):

CH ₂ = CX ₁ -COO-CHY-CH ₂ -OCO-CX ₂ = CH ₂

(Wherein X ₁ and X ₂ are each independently a hydrogen atom or a methyl group, Y is a fluoroalkyl group having 2 to 20 carbon atoms having at least 3 fluorine atoms, or a fluoroalkyl group having 4 to 20 fluoro atoms and having 4 to 20 carbon atoms Represents a cycloalkyl group.

In the present embodiment, the compound in which the polymerizable unsaturated group is a (meth) acryloyloxy group may have a plurality of (meth) acryloyloxy groups. When the fluorinated antifouling agent has a plurality of (meth) acryloyloxy groups, it exhibits a three-dimensional network structure when cured, has a high glass transition temperature, low transferability of the antifouling agent, The durability can be improved. Further, a cured coating excellent in heat resistance, weather resistance, and the like can be obtained.

Specific examples of the compound represented by the formula (F-5) include di (meth) acrylate-2,2,2-trifluoroethyl ethylene glycol, di (meth) , 3-pentafluoropropylethylene glycol, di (meth) acrylate-2,2,3,3,4,4,4-heptafluorobutylethylene glycol, di (meth) , 3,3,4,4,5,5,5-nonafluoropentyl ethylene glycol, di (meth) acrylic acid-2,2,3,3,4,4,5,5,6,6, 6-undecafluorohexyl ethylene glycol, di (meth) acrylate-2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptylethylene Glycols, di (meth) acrylate-2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctylethylene glycol, Di (meth) acrylate-3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctylethylene glycol, di (meth) (Meth) acrylic acid-2, 2,3,3,4 , 4,5,5,6,6,7,7,8,8,9,9,9,10,10,10-nonadecafluorodecyl ethylene glycol, di (meth) acrylic acid-3, 3,4 , 4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl ethylene glycol, di (meth) acrylic acid-2-trifluoro Methyl (meth) acrylate-3-trifluoromethyl-4,4,4-trifluorobutylethylene glycol, di (meth) acrylic acid Methyl-2,2,3,3,3-pentafluoropropylethylene glycol, di (meth) acrylate-1-methyl-2,2,3,3,4,4,4-heptafluoro Butyl ethylene glycol, and the like, and they can be used singly or as a mixture when used. Such a di (meth) acrylic acid ester can be produced by a known method such as that disclosed in JP-A-6-306326. In the present embodiment, the diacrylic acid-2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluorononyl ethylene glycol A lycor is preferably used.

In the present embodiment, a compound in which the polymerizable unsaturated group is a (meth) acryloyloxy group may be a compound having a plurality of (per) fluoroalkyl groups or (per) fluoropolyether groups in one molecule.

The fluorine-containing antifouling agent in the present embodiment may be any of monomers, oligomers, and polymers. The fluorine antifouling agent preferably has a substituent which contributes to the formation of a bond or compatibility in the hard coat layer coating. These substituents may be the same or different and are preferably plural. Preferred examples of the substituent include an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, a cinnamoyl group, an epoxy group, an oxetanyl group, a hydroxyl group, a polyoxyalkylene group, a carboxyl group and an amino group.

The fluorine antifouling agent may be a polymer with a compound containing no fluorine atom, or it may be an oligomer.

The fluorine-containing compound may contain a silicon atom in the molecule, may contain a siloxane structure, or may have a structure other than a siloxane structure. However, when the fluorinated compound having a polymerizable unsaturated group contains a siloxane structure, the weight average molecular weight is less than 15,000.

When the fluorinated compound contains a siloxane structure, the fluorinated compound is preferably represented by the following formula (F-6).

Formula (F-6):

^{_{R a R f b R A c}} SiO (4-abc) / 2

(Wherein R is a hydrogen atom, a methyl group, an ethyl group, a propyl group or a phenyl group, R ^f is an organic group containing a fluorine atom, R ^A is an organic group containing a polymerizable unsaturated group, b, 0 < c, a + b + c <

a is preferably from 1 to 1.75, more preferably from 1 to 1.5, and if it is more than 1, the synthesis of the compound becomes industrially easy, and when it is 1.75 or less, both the curing property and the antifouling property become easy.

As the polymerizable unsaturated group in R ^A, there can be an identical polymerizable unsaturated group and R _A in the formula (F), preferably in time-yloxy a group, (meth) acrylic (meth) acrylate, and mixtures thereof Group is a group in which any hydrogen atom is substituted with a fluorine atom.

When the fluorine compound contains a siloxane structure, preferred examples of the siloxane structure include a structure having a substituent at the terminal and / or side chain of a compound chain containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different and are preferably plural. Examples of preferred substituents include (meth) acryloyl groups, (meth) acryloyloxy groups, vinyl groups, allyl groups, cinnamoyl groups, epoxy groups, oxetanyl groups, hydroxyl groups, fluoroalkyl groups, polyoxyalkylene groups, (Meth) acryloyloxy group is preferable from the viewpoint of suppressing the bleed-out of the antifouling agent. As the number of substituents, 1,500 to 20,000 g.mol.sup.- ¹ in terms of the functional group equivalent is preferable in view of improvement of ellipticity of the antifouling agent and suppression of bleed-out.

R ^f is an organic group containing a fluorine atom and is a group represented by C _x F _{2x + 1} (CH ₂ ) _p - (wherein x is an integer of 1 to 8 and p is an integer of 2 to 10) Is preferably a polyether-substituted alkyl group. b is preferably from 0.2 to 0.4, more preferably from 0.2 to 0.25, and if it is 0.2 or more, the antifouling property is improved. If it is 0.4 or less, the curing property is improved. R ^f is preferably a perfluoroalkyl group having 8 carbon atoms.

R ^A is an organic group containing a (meth) acryl group, and it is more preferable that the bond to the Si atom is Si-OC bond because of easiness in industrial synthesis. c is preferably 0.4 to 0.8, and more preferably 0.6 to 0.8. When the ratio is 0.4 or more, the curing property is improved. When the ratio is 0.8 or less, the antifouling property is improved.

The value of a + b + c is preferably 2 to 2.7, more preferably 2 to 2.5. If it is smaller than 2, it is difficult for the surface to be unevenly distributed. On the other hand, if it is larger than 2.7, .

When the fluorine compound contains a siloxane structure, the fluorine compound preferably has 3 or more F atoms and 3 or more Si atoms, preferably 3 to 17 F atoms and 3 to 17 Si atoms in one molecule, It is preferable to contain 8 units. When the number of F atoms is 3 or more, the antifouling property becomes sufficient. When the number of Si atoms is 3 or more, the surface is uniformly flattened and the antifouling property becomes sufficient.

When the fluorine-containing compound contains a siloxane structure, the fluorine-containing compound can be produced by a known method such as that disclosed in JP-A-2007-145884.

When the fluorine-containing compound contains a siloxane structure, the siloxane structure may be any of linear, branched, and cyclic. Of these, the compound having a branched or cyclic structure is preferably a siloxane structure having an unsaturated double bond Is preferable because it has good compatibility with a compound having a covalent bond, has no cissing, and is easily prone to surface unevenness.

Here, as the compound having a siloxane structure and a branched structure, a compound represented by the following formula (F-7) is preferable.

Formula (F-7):

R ^f SiR _k [OSiR _m (OR ^A ) _3-m ] _3-k

(Wherein R, R ^f and R ^A are as defined above, m = 0, 1 or 2, in particular m = 2, and k = 0 or 1.)

As the compound having a siloxane structure having a cyclic structure, a compound represented by the following formula (F-8) is preferable.

Formula (F-8):

(R ^f RSiO) (R ^A RSiO) _{n wherein} R, R ^f and R ^A are the same as above and n = 2, in particular 3? N? 5.

Specific examples of such fluorine-containing polysiloxane compounds include the following compounds.

(11)

The weight average molecular weight (Mw) of the fluorine antifouling agent can be measured by molecular reversion chromatography, for example, gel permeation chromatography (GPC). The Mw of the fluororesin antifouling agent used in the present embodiment is preferably 400 or more and less than 5,000, more preferably 1,000 or more and less than 5,000, and still more preferably 1,000 or more and 3,500 or less. When the Mw is 400 or more, the antifouling agent is preferable because surface migration is increased. When the Mw is less than 5,000, the surface smoothness of the fluorine-containing antifouling agent can not be interrupted between the coating and curing steps, and the antifouling property and the film hardness are improved because the fluororesin is easily aligned uniformly on the surface of the hard coat layer desirable.

However, when the fluorinated compound contains a siloxane structure, Mw is less than 15,000, preferably 1000 or more and less than 5000, and more preferably 1000 or more and less than 3,500.

The amount of the fluorine antifouling agent to be added is preferably 1 to 20 mass%, more preferably 1 to 15 mass%, and more preferably 1 to 10 mass%, based on the total solid content in the composition for forming a hard coat layer or hard coat layer desirable. When the addition amount of the fluorine-containing antifouling agent is 1% by mass or more based on the total solid content in the composition for forming the hard coat layer or the hard coat layer, the proportion of the antifouling agent having water-repellent and oil-repellent property becomes adequate and sufficient antifouling property can be obtained. When the addition amount of the fluorine-containing antifouling agent is 20% by mass or less based on the total solid content in the composition for forming a hard coat layer or hard coat layer, the antifouling agent which can not be mixed with the resin component is not precipitated on the surface, It is preferable since it does not generate a white powder.

The fluorine atom content of the fluorine antifouling agent is not particularly limited, but is preferably 20% by mass or more, more preferably 30 to 70% by mass, most preferably 40 to 70% by mass.

Examples of preferred fluorinated antifouling agents include: R-2020, M-2020, R-3833, M-3833 and Optul DAC (trade name) manufactured by Daikin Kagaku Kogyo K.K., Megafac F- -172, F-179A, Defensor MCF-300, MCF-323 (trade name), and the like.

[Polysiloxane compound having a polymerizable unsaturated group and having a weight average molecular weight of 15000 or more]

Next, the polysiloxane compound having a polymerizable unsaturated group and having a weight average molecular weight of 15000 or more, which can be used as the component g) will be described. Hereinafter, the polysiloxane compound having a molecular weight of 15000 or more is referred to as "polysiloxane antifouling agent ".

One preferred example of the polysiloxane antifouling agent is a compound represented by the above formula (F-6).

Preferable examples of the polysiloxane antifouling agent include compounds having a substituent at the terminal and / or side chain of a compound chain containing a plurality of dimethylsilyloxy units as repeating units. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy. The substituents may be the same or different and are preferably plural. Examples of preferred substituents include (meth) acryloyl groups, (meth) acryloyloxy groups, vinyl groups, allyl groups, cinnamoyl groups, epoxy groups, oxetanyl groups, hydroxyl groups, fluoroalkyl groups, polyoxyalkylene groups, (Meth) acryloyloxy group is preferable from the viewpoint of suppressing the bleed-out of the antifouling agent. As the number of substituents, 1,500 to 20,000 g.mol.sup.- ¹ as the functional group equivalent is preferable in view of the improvement of the ubiquity of the antifouling agent and the suppression of bleed-out.

The polysiloxane antifouling agent is preferably a compound containing 3 or more F atoms and 3 or more Si atoms, preferably 3 to 17 F atoms and 3 to 8 Si atoms in one molecule. When the number of F atoms is 3 or more, the antifouling property becomes sufficient. When the number of Si atoms is 3 or more, the surface is uniformly flattened and the antifouling property becomes sufficient.

Polysiloxane antifouling agents can be produced by using known methods such as those disclosed in Japanese Patent Application Laid-Open No. 2007-145884.

X-22-169AS "," KF-102 "," X-22-3701IE ", and" X-22- X-22-173AS "," X-22-162AS "," X-22-173B "," X-22-174D " Manufactured by Kagaku Kogyo Co., Ltd.; Quot; AK-5 ", "AK-30 "," AK- 32 "(trade name) manufactured by Soko Dojo Kosei Co., &Quot; Sililla Plain FM0725 ", "Sililla Plain FM0721" (trade name) manufactured by JNC Corporation; It is also preferable to add "DMS-U22", "RMS-033", "UMS-182" (trade name) Silicone-based compounds can also be preferably used.

As the siloxane structure contained in the polysiloxane antifouling agent, any of linear, branched and cyclic structures may be used. Among these compounds, a compound having a branched or cyclic structure is particularly preferable because of its compatibility with a compound having an unsaturated double bond Is preferable because there is no sissing, and the surface is liable to be unevenly distributed.

The weight average molecular weight of the polysiloxane antifouling agent is 15,000 or more, preferably 15,000 or more and 50,000 or less, and more preferably 18,000 or more and 30,000 or less. When the weight average molecular weight of the polysiloxane antifouling agent is less than 15,000, the surface unevenness of the polysiloxane is reduced, which is not preferable from the viewpoint of deteriorating antifouling property and lowering hardness. However, when the fluorine-containing compound having a polymerizable unsaturated group has a polysiloxane structure, the above problem does not occur.

The weight average molecular weight of the polysiloxane antifouling agent can be measured by molecular reversion chromatography, for example, gel permeation chromatography (GPC).

The amount of the polysiloxane antifouling agent to be added is preferably 1% by mass or more and less than 25% by mass, more preferably 1% by mass or more and less than 20% by mass based on the total solid content in the composition for forming a hard coat layer or hard coat layer, More preferably not less than 15% by mass, and most preferably not less than 1% by mass and less than 10% by mass. If the addition amount of the polysiloxane antifouling agent is 1% by mass or more based on the total solid content in the composition for forming the hard coat layer or the hard coat layer, the proportion of the antifouling agent having water repellent or oil repellent property becomes adequate and sufficient antifouling property can be obtained. If the addition amount of the polysiloxane antifouling agent is less than 25 mass% with respect to the total solid content in the composition for forming a hard coat layer or hard coat layer, the antifouling agent which can not be mixed with the resin component is not precipitated on the surface, It is preferable because it does not generate a white powder.

The distribution of the antifouling agent in the film thickness direction in the hard coat layer can be obtained when X is the amount of fluorine or silicon near the surface of the hard coat layer and Y is the amount of fluorine or silicon in the entire hard coat layer , And 51% < X / Y < 100%. When X / Y is larger than 51%, the antifouling agent is not distributed to the inside of the film of the hard coat layer, and is preferable from the standpoint of antifouling property and film hardness. Further, the vicinity of the surface refers to a region of a depth of less than 1 mu m from the surface of the hard coat layer and refers to an area of the F-fragment or Si ₂ C ₅ H ₁₅ O ⁺ fragment measured by flight time secondary ion mass spectrometry (TOF-SIMS) The ratio can be measured.

g) The antifouling agent is preferably an antifouling agent dissolving in a liquid or a solvent at 20 占 폚. The solvent may be appropriately selected according to the polarity of the compound, but an organic solvent which is miscible with dimethyl carbonate is preferable, and aliphatic or aromatic alcohols, ketones, esters and ether solvents can be exemplified. It is particularly preferable to dissolve in dimethyl carbonate.

g) The surface tension of the antifouling agent is preferably 25.0 mN / m or less, more preferably 23.0 mN / m or less, and most preferably 16.0 mN / m or less in view of antifouling property.

The surface tension of the antifouling agent is the surface tension in the monolayer, which can be measured in the following manner.

(Method of measuring the surface tension of the antifouling agent)

The antifouling agent was spin-coated on the quartz substrate, and when the solvent was contained, the antifouling agent was dried to produce a film. Subsequently, using pure water as a liquid at a dry state (20 DEG C / 65% RH) using a contact angle meter ("CA-X" type contact angle meter, manufactured by Kyowa Chemical & Was made at the tip of the needle, and this was brought into contact with the surface of the spin-coated film to form droplets on the film. The angle between the tangent to the liquid surface and the film surface at the point of contact between the film and the liquid was measured with the angle of the side containing the liquid as the contact angle. Further, the contact angle was measured using methylidene iodide instead of water, and the surface free energy was determined from the following equation.

The surface free energy (? S ^v : unit, mN / m) is DK Owens: J. Appl. Polym. From the contact angles θ _H2O and θ _CH2I2 of pure H ₂ O and iodinated methylene CH ₂ I ₂ experimentally obtained on the antireflection film with reference to the reference _numerals a and b value represented by the sum of the calculated γs ^d and γs ^h from ^{γs v (= γs d + γs} h) was defined as.

a. ^{_{1 + cosθ H2O = 2√γs d (}} √γ H2O d / γ H2O v) + 2√γs h (√γ H2O h / γ H2O v)

b. ^{_{1 + cosθ CH2I2 = 2√γs d (}} √γ CH2I2 d / γ CH2I2 v) + 2√γs h (√γ CH2I2 h / γ CH2I2 v) γ H2O d = 21.8, γ H2O h = 51.0, γ H2O v = 72.8 _{,? CH2I2} ^d = 49.5 _{,? CH2I2} ^h = 1.3 _{,? CH2I2} ^v = 50.8

As the g) antifouling agent described above, a compound synthesized by a known method may be used, or a commercially available product may be used. As a commercially available product, RS-90 and RS-78 manufactured by DIC Corporation can be preferably used.

(menstruum)

The composition for forming a hard coat layer in this embodiment may contain a solvent. The solvent is not particularly limited as long as it can dissolve or disperse the respective components, can be easily formed into a uniform surface shape in the coating step and the drying step, can maintain liquid storage stability, has a suitable saturated vapor pressure, A solvent may be used.

The solvent can be used by mixing two or more kinds of solvents. Particularly, from the viewpoint of the drying load, it is preferable that a main component is a solvent having a boiling point of 100 占 폚 or less at normal pressure room temperature, and a small amount of a solvent having a boiling point of 100 占 폚 or more is contained for adjusting the drying rate.

In the composition for forming a hard coat layer in the present embodiment, it is preferable that a solvent having a boiling point of 80 캜 or lower is contained in the total solvent of the coating composition in an amount of 30 to 80 mass%, preferably 50 to 70 More preferably, it contains a mass. By setting the ratio of the molar ratio at the boiling point of 80 DEG C or less to the above ratio, the absorption of the resin component into the polyester film is suitably suppressed, and the sedimentation of particles can be suppressed by increasing the rate of viscosity increase due to drying.

Examples of the solvent having a boiling point of 100 ° C or less include hydrocarbons such as hexane (boiling point 68.7 ° C), heptane (98.4 ° C), cyclohexane (80.7 ° C) and benzene (80.1 ° C) Halogenated hydrocarbons such as chloroform (39.8 占 폚), chloroform (61.2 占 폚), carbon tetrachloride (76.8 占 폚), 1,2-dichloroethane (83.5 占 폚), and trichlorethylene Ethyl formate (54.2 占 폚), methyl acetate (57.8 占 폚), tetrahydrofuran (70 占 폚), and the like, such as diethyl ether (34.6 占 폚), diisopropyl ether Esters such as ethyl acetate (77.1 C) and isopropyl acetate (89 C), ketones such as acetone (56.1 C) and 2-butanone (methyl ethyl ketone, same as MEK, 79.6 C) 2-propanol (82.4 占 폚) and 1-propanol (97.2 占 폚), cyano compounds such as acetonitrile (81.6 占 폚) and propionitrile (97.4 占 폚), 2 Carbon sulphide (46.2 ) And the like. Of these, ketones and esters are preferable, and ketones are particularly preferable. Of the ketones, 2-butanone is particularly preferred.

Examples of the solvent having a boiling point exceeding 100 캜 include octane (125.7 캜), toluene (110.6 캜), xylene (138 캜), tetrachlorethylene (121.2 캜), chlorobenzene 101.3 C), dibutyl ether (142.4 C), isobutyl acetate (118 C), cyclohexanone (155.7 C), 2-methyl-4-pentanone (same as MIBK, 115.9 C) (117.7 占 폚), N, N-dimethylformamide (153 占 폚), N, N-dimethylacetamide (166 占 폚) and dimethylsulfoxide (189 占 폚). Preferably, it is cyclohexanone, 2-methyl-4-pentanone.

(Surfactants)

It is also preferable to use various surfactants and / or an anti-wind non-uniformity agent (hereinafter also referred to as &quot; whole-body surface-active agent &quot;) for the hard coat layer or hard coat layer composition in the present embodiment. Generally, the surfactant and / or the anti-wind non-uniforming agent can suppress the unevenness of the film thickness due to the drying imbalance due to the local distribution of the dry wind.

As the surfactant, specifically, it is preferable to contain a fluorine-based surfactant, a silicon-based surfactant, or both. It is preferable that the surfactant is an oligomer or polymer rather than a low-molecular compound.

Preferable examples of the fluorine-based surfactant include a fluoroaliphatic group-containing copolymer (hereinafter also abbreviated as "fluorine-based polymer"), and the fluorine-based polymer includes repeating units corresponding to monomers of the following (i) , Or an acrylic resin, a methacrylic resin, and a copolymer of vinyl-based monomers copolymerizable therewith, which comprises a repeating unit corresponding to the monomer of (i) and a repeating unit corresponding to the monomer of (ii) Coalescing is useful.

(i) a fluoroaliphatic group-containing monomer represented by the following formula (i)

(I)

[Chemical Formula 12]

In formula (i), R ¹¹ represents a hydrogen atom or a methyl group, X represents an oxygen atom, a sulfur atom or -N (R ¹² ) -, m is an integer of 1 to 6, n is an integer of 2 to 4 . R ¹² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, specifically, a methyl group, an ethyl group, a propyl group or a butyl group, preferably a hydrogen atom or a methyl group. X is preferably an oxygen atom.

(ii) a monomer represented by the following formula (ii) copolymerizable with the above (i)

(Ii)

[Chemical Formula 13]

In formula (ii), R ¹³ represents a hydrogen atom or a methyl group, Y represents an oxygen atom, a sulfur atom or -N (R ¹⁵ ) -, R ¹⁵ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Is a methyl group, an ethyl group, a propyl group or a butyl group, preferably a hydrogen atom or a methyl group. Y is an oxygen atom, -N (H) -, and -N (CH ₃₎ - is the preferred.

R ¹⁴ represents a linear, branched or cyclic alkyl group having 4 to 20 carbon atoms which may have a substituent. Examples of the substituent of the alkyl group for R ¹⁴ include a halogen atom such as a hydroxyl group, an alkylcarbonyl group, an arylcarbonyl group, a carboxyl group, an alkylether group, an arylether group, a fluorine atom, a chlorine atom and a bromine atom, An amino group, and the like, but are not limited thereto. Examples of the straight, branched or cyclic alkyl group having 4 to 20 carbon atoms include linear or branched alkyl groups such as butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, , A tetradecyl group, a pentadecyl group, an octadecyl group and an eicosanyl group, and monocyclic cycloalkyl groups such as a cyclohexyl group and a cycloheptyl group, and bicycloheptyl groups such as a bicyclohexyl group, a bicyclodecyl group, a tricyclododecyl group, A polycyclic cycloalkyl group such as an acyl group, an adamantyl group, a norbornyl group and a tetracyclodecyl group is suitably used.

The amount of the fluoroaliphatic group-containing monomer represented by the formula (i) used in the fluoropolymer is 10 mol% or more, preferably 15 to 70 mol%, based on each monomer of the fluoropolymer, 20 to 60 mol%.

The weight average molecular weight of the fluorine-based polymer is preferably from 3,000 to 100,000, more preferably from 5,000 to 80,000. The amount of the fluorine-based polymer to be added is preferably 0.001 to 5 parts by mass, more preferably 0.005 to 3 parts by mass, and more preferably 0.01 to 1 part by mass based on 100 parts by mass of the coating liquid. If the addition amount of the fluorine-based polymer is 0.001 parts by mass or more, the effect of adding the fluorine-based polymer is sufficiently obtained. If the amount is less than 5 parts by mass, the coating film can not be dried sufficiently or adversely affects the performance as a coating film Do not.

Examples of preferable silicone compounds include X-22-174DX, X-22-2426, X22-164C and X-22-176D (trade names, available from Shin-Etsu Chemical Co., Ltd.); FM-7725, FM-5521 and FM-6621 (trade names, available from JNC); DMS-U22 of Gelest, RMS-033 (trade name); SH200, DC11PA, ST80PA, L7604, FZ-2105, L-7604, Y-7006 and SS-2801 (trade names) available from Toray Dow Corning Incorporated; And TSF400 (trade name) made by Momentive Performance Materials, Japan. However, the present invention is not limited to these.

When the total solid content of the composition for forming a hard coat layer in the present embodiment is 100 mass%, the silicone surfactant is preferably contained in an amount of 0.01 to 0.5 mass%, more preferably 0.01 to 0.3 mass%.

(Mat particles)

The composition for forming a hard coat layer or a hard coat layer may contain mat particles having an average particle diameter of 1.0 to 15.0 占 퐉, preferably 1.5 to 10.0 占 퐉, for the purpose of imparting an internal scattering property or imparting surface unevenness. In order to adjust the viscosity of the coating liquid, a polymer compound or an inorganic layer compound may be contained. e) may be used as the matte particles.

The hard coat film according to an embodiment of the present disclosure may include another layer (arbitrary layer) in addition to the polyester film and the hard coat layer according to the above-described embodiment. Examples of such an optional layer include an adhesive layer, an antireflection layer (a laminated film of one or more high refractive index layers and one or more low refractive index layers), an antiglare layer, and an antistatic layer, but are not limited thereto Do not. For these arbitrary layers, reference can be made, for example, to paragraphs 0069 to 0091 of Japanese Patent Publication No. 5048304 and the like. The hard coat film according to the present embodiment may be provided with a decorative layer.

Examples of the preferable layer structure of the hard coat film according to the present embodiment are shown below, but the present invention is not limited thereto.

· Polyester film / hard coat layer

Polyester film / hard coat layer / low refractive index layer

Polyester film / hard coat layer / antiglare layer (antistatic layer) / low refractive index layer,

Polyester film / hard coat layer / antiglare layer / antistatic layer / low refractive index layer,

Polyester film / hard coat layer / antistatic layer / antiglare layer / low refractive index layer,

Polyester film / hard coat layer (antistatic layer) / antiglare layer / low refractive index layer,

Polyester film / hard coat layer / high refractive index layer / antistatic layer / low refractive index layer,

Polyester film / hard coat layer / high refractive index layer (antistatic layer) / low refractive index layer,

Polyester film / hard coat layer / antistatic layer / high refractive index layer / low refractive index layer,

Polyester film / hard coat layer / medium refractive index layer / high refractive index layer (antistatic layer) / low refractive index layer,

Polyester film / hard coat layer / medium refractive index layer (antistatic layer) / high refractive index layer / low refractive index layer,

Polyester film / hard coat layer (antistatic layer) / medium refractive index layer / high refractive index layer / low refractive index layer,

Polyester film / antistatic layer / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,

Antistatic layer / polyester film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,

Here, the antistatic layer and the antiglare layer may have hard coat properties.

(Low refractive index layer)

The hard coat film according to the present embodiment may form a low refractive index layer on the hard coat layer for the purpose of imparting the effect of reducing the reflectance. The low refractive index layer has a refractive index lower than that of the hard coat layer and preferably has a thickness of 50 to 200 nm, more preferably 70 to 150 nm, most preferably 80 to 120 nm.

The refractive index of the low refractive index layer is lower than the refractive index of the layer immediately below and is preferably 1.20 to 1.55, more preferably 1.25 to 1.46, and particularly preferably 1.30 to 1.40.

The thickness of the low refractive index layer is preferably 50 to 200 nm, more preferably 70 to 100 nm.

The low refractive index layer is preferably obtained by curing the curable composition for forming the low refractive index layer.

As a preferable embodiment of the curable composition of the low refractive index layer,

(1) a composition containing a fluorine compound having a crosslinkable or polymerizable functional group,

(2) a composition comprising, as a main component, a hydrolyzed condensate of an organosilane material of fluorine,

(3) a composition containing a monomer having two or more ethylenic unsaturated groups and an inorganic particle (preferably an inorganic particle having a hollow structure in particular), and the like.

It is preferable that each of the compositions (1) and (2) contain inorganic particles. When inorganic particles having a hollow structure with a low refractive index are used, the refractive index can be reduced or the amount of inorganic particles added and the refractive index can be adjusted .

(1) a composition containing a fluorine compound having a crosslinkable or polymerizable functional group

Examples of the fluorine-containing compound having a crosslinkable or polymerizable functional group include a fluorine-containing polymer that is a copolymer of a fluorine-containing monomer and a monomer having a crosslinkable or polymerizable functional group. Specific examples of these fluorine-containing polymers are described in JP-A-2003-222702 and JP-A-2003-183322.

The fluorine-containing polymer may be used in combination with a curing agent having a polymerizable unsaturated group suitably as described in JP-A-2000-17028. Also, as described in Japanese Patent Laid-Open No. 2002-145952, it is also preferable to use it in combination with a compound having fluorinated polyfunctional polymerizable unsaturated group. Examples of the compound having a polyfunctional polymerizable unsaturated group include monomers having two or more ethylenically unsaturated groups described above as the curable resin compound of the low refractive index layer. The hydrolyzed condensate of the organosilane described in JP 2004-170901 A is also preferable, and the hydrolyzed condensate of the organosilane containing the (meth) acryloyl group is particularly preferable. These compounds are particularly preferable in the case of using a compound having a polymerizable unsaturated group in the polymer main body, because of the combined effect of improvement in scratch resistance.

When the polymer itself does not have sufficient curability, it is possible to impart necessary curability by blending a crosslinkable compound. For example, when the polymer main body contains a hydroxyl group, it is preferable to use various amino compounds as a curing agent. The amino compound used as the crosslinking compound is, for example, a compound containing at least two or more of a hydroxyalkylamino group and an alkoxyalkylamino group in total, and specifically includes, for example, a melamine compound, a urea Based compounds, benzoguanamine-based compounds, glycoluril-based compounds, and the like. For the curing of these compounds, it is preferable to use an organic acid or a salt thereof.

(2) Composition comprising a hydrolyzed condensate of a fluorine-containing organosilane material as a main component

A composition comprising a hydrolyzed condensate of an organosilane compound having fluorine as a main component is also preferable because it has a low refractive index and a high surface hardness of the coating film. A condensation product of a compound containing hydrolyzable silanol at one terminal or both terminals with a fluorinated alkyl group and a condensate of tetraalkoxysilane are preferable. Specific compositions are described in JP-A-2002-265866 and JP-A-317152.

(3) a composition containing a monomer having two or more ethylenically unsaturated groups and an inorganic particle having a hollow structure

As another preferred embodiment, a low refractive index layer made of particles having a low refractive index and a resin can be given. The low refractive index particles may be organic or inorganic, but particles having voids therein are preferable. Specific examples of hollow particles include silica-based particles described in JP-A-2002-79616. The particle refractive index is preferably 1.15 to 1.40, more preferably 1.20 to 1.30. As the resin, there may be mentioned monomers having two or more ethylenic unsaturated groups described in the page of the antiglare layer.

It is preferable to add a photo radical polymerization initiator or a thermal radical polymerization initiator to the composition for forming the low refractive index layer used in the present embodiment. When a radical polymerizing compound is contained, a polymerization initiator of 1 to 10 parts by mass, preferably 1 to 5 parts by mass, based on the above compound can be used.

In the low refractive index layer used in the present embodiment, inorganic particles can be used in combination. Particles having a particle diameter of 15% to 150%, preferably 30% to 100%, and more preferably 45% to 60% of the thickness of the low refractive index layer can be used to impart scratch resistance.

A known polysiloxane-based or fluorine-based antifouling agent, a sliding agent and the like can be suitably added to the low refractive index layer used in the present embodiment for the purpose of imparting properties such as antifouling property, water resistance, chemical resistance and sliding property.

Examples of the additive having a polysiloxane structure include a reactive group-containing polysiloxane {e.g., KF-100T, X-22-169AS, KF-102, X-22-37-01IE, X-22-164B, X-22-5002 , X-22-173B, X-22-174D, X-22-167B, X-22-161AS (trade name), manufactured by Shin-Etsu Chemical Co., AK-5, AK-30, AK-32 (trade name) manufactured by Soko Dojo Kosei; , &Quot; SILLA PLAIN FM0725 ", "SILLA PLAIN FM0721" (trade name) manufactured by JNC Corporation). The silicone compounds described in Tables 2 and 3 of Japanese Patent Laid-Open No. 2003-112383 are also preferably used.

As the fluorine-based compound, a compound having a fluoroalkyl group is preferable. In the fluoroalkyl group is preferably from 1 to 20 carbon atoms, and more preferably from 1 to 10, straight chain (e.g., _{-CF 2 CF 3, -CH 2 (} CF 2) 4 H, -CH 2 (CF 2 _{) 8 CF 3, -CH 2 CH} 2 (CF 2) 4 H being even, and so on), for the branched structure (for example, _{CH (CF 3) 2, CH} 2 CF (CF 3) 2, CH (CH 3) CF 2 CF ₃ , CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.), and an alicyclic structure (preferably a 5-membered ring or 6-membered ring such as a perfluorocyclohexyl group, a perfluorocyclopentyl group Or an alkyl group substituted with them), or may have an ether bond (for example, CH ₂ OCH ₂ CF ₂ CF ₃ , CH ₂ CH ₂ OCH ₂ C ₄ F ₈ H, CH ₂ CH ₂ OCH ₂ CH ₂ C ₈ F ₁₇ , CH ₂ CH ₂ OCF ₂ CF ₂ OCF ₂ CF ₂ H, etc.). A plurality of the fluoroalkyl groups may be contained in the same molecule.

It is preferable that the fluorine-based compound further has a substituent which contributes to bond formation or compatibility with the low-refractive-index layer coating. The substituents may be the same or different, and it is preferable that the substituents are plural. Preferred examples of the substituent include an acryloyl group, a methacryloyl group, a vinyl group, an aryl group, a cinnamoyl group, an epoxy group, an oxetanyl group, a hydroxyl group, a polyoxyalkylene group, a carboxyl group and an amino group. The fluorine-based compound may be a polymer with a compound containing no fluorine atom, or may be an oligomer, and the molecular weight is not particularly limited. The fluorine atom content of the fluorine-based compound is not particularly limited, but is preferably 20 mass% or more, more preferably 30 to 70 mass%, and most preferably 40 to 70 mass%. Examples of preferred fluorine-based compounds include: R-2020, M-2020, R-3833, M-3833 and Optul DAC (trade name) manufactured by Daikin Chemical Industries, Ltd., Megafac F- , F-179A, Dispenser MCF-300, MCF-323 (trade name), and the like.

These polysiloxane fluorine-based compounds or compounds having a polysiloxane structure are preferably added in a range of 0.1 to 10 mass%, particularly preferably 1 to 5 mass%, based on the total solid content of the low refractive index layer.

[Method of applying hard coat layer]

The hard coat layer relating to the hard coat film of the present disclosure can be formed by the following method.

First, a composition for forming a hard coat layer is prepared. Next, the composition is coated on a polyester film (base film) by a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method or a die coating method, · Dry. A micro-gravure coating method, a wire bar coating method and a die coating method (see U.S. Patent No. 2681294 and Japanese Unexamined Patent Application Publication No. 2006-122889) are more preferable, and a die coating method is particularly preferable.

The hard coat layer is applied to the substrate film and then conveyed to the web in a heated zone for drying the solvent. The temperature of the drying zone at that time is preferably 25 ° C to 140 ° C, the first half of the drying zone is relatively low temperature, and the second half is preferably relatively high temperature. However, it is preferable that the temperature is not higher than the temperature at which volatilization of components other than the solvent contained in the coating composition of each layer starts. For example, some commercially available photo-radical generating agents used in combination with ultraviolet curing resins are volatilized about 10% within several minutes in hot air at 120 ° C. In addition, monofunctional, bifunctional acrylate monomers, etc., And volatilization proceeds in the warm air of. In such a case, it is preferable that the temperature of the hard coat layer is not more than the temperature at which volatilization of components other than the solvent contained in the coating composition starts.

It is preferable that the drying air after the application of the coating composition of the hard coat layer on the base film has an air velocity of the coating film surface of 0.1 to 2 m / sec when the solid content concentration of the coating composition is 1 to 50% It is preferable to prevent drying unevenness.

When the coating composition of the hard coat layer is coated on the base film and the temperature difference between the carrier roll and the base film which come into contact with the surface opposite to the coating surface of the base film in the drying zone is within 0 ° C to 20 ° C, Drying unevenness due to non-uniform heat transfer on the conveying roll can be prevented.

After the drying zone of the solvent, the coating film is cured by passing the zone through which the hard coat layer is cured by ionizing radiation on the web. For example, if the coating is UV-curing, it is preferred that the irradiation dose of ultraviolet ray of ^{10mJ / cm 2 ~ 1000mJ / cm} 2 to cure the coating film by the ultraviolet lamp. At this time, the distribution of the dose in the width direction of the web is preferably 50 to 100%, more preferably 80 to 100%, including both ends to the maximum central dose. When it is necessary to lower the oxygen concentration by purging the nitrogen gas or the like to promote the surface hardening, the oxygen concentration is preferably 0.01% to 5%, and the distribution in the width direction is preferably 2% or less in oxygen concentration. In case of ultraviolet irradiation, ultraviolet rays emitted from light such as ultrahigh pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halide lamp and the like can be used. In order to accelerate the curing reaction, the temperature may be increased during curing. The temperature is preferably 25 to 100 占 폚, more preferably 30 to 80 占 폚, and most preferably 40 to 70 占 폚.

It is also possible to provide other functional layers as required. In the case of laminating other functional layers in addition to the hard coat layer, a plurality of layers may be coated simultaneously or sequentially. The method for producing these layers can be performed in accordance with the method for producing the hard coat layer.

The use of the polyester film according to the present embodiment is not particularly limited and can be suitably used for applications requiring suppression of the occurrence of concave portions when a load is applied.

The polyester film according to the present embodiment can be suitably used as a substrate film of various functional films such as a sensor film for a touch panel, a scattering prevention film, and an anti-reflection film in addition to a base film of a hard coat film.

[Shatterproof film]

The anti-scattering film according to the present embodiment is a anti-scattering film in which an adhesive layer is laminated on at least one surface of the polyester film according to the present embodiment. The polyester film according to the present embodiment can be used for a scattering prevention film. The anti-scattering film is preferably a polyester film laminated with a hard coat layer and an adhesive layer.

The adhesive layer may be formed by any one of a wet coating method and a dry coating method. To form the pressure-sensitive adhesive layer, an acrylic pressure-sensitive adhesive composition such as a solvent-based acrylic polymer or a solvent-based acrylic syrup, a solventless acrylic syrup, or a solventless urethane acrylate may be used.

[Antireflection Film]

The antireflection film according to the present embodiment is an antireflection film in which an antiglare layer is laminated on at least one surface of a polyester film according to the present embodiment. The polyester film according to the present embodiment can be used for an antireflection film.

The antiglare layer may be formed by any one of a wet coating method and a dry coating method. In the antiglare layer, there are disclosed in Japanese Laid-Open Patent Publication Nos. 2014-059334, 2014-026122, 2014-016602, 2014-016476, 2014-041206, 2014- 032317, JP-A-2014-026123 and JP-A-2014-010316 can be used.

[Sensor Film for Touch Panel]

The sensor film for a touch panel according to the present embodiment is a sensor film for a touch panel including the polyester film according to the present embodiment. The polyester film according to the present embodiment can be used for a sensor film for a touch panel. The sensor film for a touch panel preferably has a hard coat layer and a transparent conductive layer laminated on a polyester film.

As a general method of forming the transparent conductive layer, there are a PVD (physical vapor deposition) method such as a sputtering method, a vacuum deposition method and an ion plating method, a CVD (Chemical Vapor Deposition) method, a coating method and a printing method. The material for forming the transparent conductive layer is not particularly limited and examples thereof include indium tin oxide (ITO), tin oxide, copper, silver, aluminum, nickel, chromium and the like. .

Before forming the transparent conductive layer, an undercoat layer for improving transparency or optical characteristics may be provided. Further, in order to improve the adhesion, a metal layer composed of a single metal element or an alloy of two or more metal elements may be provided between the undercoat layer and the polyester film. The metal layer is preferably a metal selected from the group consisting of silicon, titanium, tin and zinc.

[Image display device]

The image display apparatus according to the present embodiment includes an image display element and a hard coat film according to the present embodiment, and a hard coat film is disposed on the outermost surface.

Examples of the image display device according to the present embodiment include an image display device such as a liquid crystal display (LCD), a plasma display panel, an electroluminescence display, and a cathode-ray tube display device.

Examples of the liquid crystal display device include liquid crystal display devices such as TN (Twisted Nematic) type, STN (Super-Twisted Nematic) type, TSTN (Triple Super Twisted Nematic) (Optically Compensated Bend) type, and the like.

The image display apparatus is preferably a liquid crystal display device including a liquid crystal cell and a polarizing plate according to the present embodiment disposed on at least one surface of the liquid crystal cell and the hard coat film according to the present embodiment is disposed on the outermost surface Do. In this case, the image display element is a liquid crystal display element.

In the image display apparatus according to the present embodiment, it is also preferable that the image display element is an organic electroluminescence display element.

[Touch Panel]

The touch panel according to the present embodiment includes the hard coat film according to the present embodiment, and the hard coat film is disposed on the outermost surface.

The touch panel to which the hard coat film according to the present embodiment can be applied is not particularly limited and can be appropriately selected according to the purpose. For example, a surface-type capacitive touch panel, a projection-type capacitive touch panel, and a resistive-film-type touch panel. The details will be described later as the resistive film touch panel according to the present embodiment and the capacitive touch panel according to the present embodiment.

The touch panel includes a so-called touch sensor and a touch pad. The layer configuration of the touch panel sensor electrode portion in the touch panel is a combination of two bonding methods of bonding transparent electrodes, a method of providing transparent electrodes on both surfaces of one substrate, a one-side jumper or a through hole method, . In addition, the projection type capacitive touch panel is preferably driven by AC (alternating current) rather than DC (direct current) driving, and more preferably, a driving method in which a voltage application time for an electrode is small.

(Resistive touch panel)

The resistive film type touch panel according to the present embodiment is a resistive film type touch panel including the hard coat film according to the present embodiment.

The resistive film touch panel has a basic structure in which conductive films of a pair of upper and lower substrates having conductive films are arranged to face each other through spacers. Furthermore, the structure of the resistive touch panel is known, and in the present embodiment, the known technology can be applied without limitation.

(Capacitive touch panel)

The capacitive touch panel according to the present embodiment is a capacitive touch panel including the hard coat film according to the present embodiment.

Examples of capacitive touch panel systems include surface-type capacitive capacitors, projection capacitive capacitors, and the like. The projection type capacitive touch panel has a basic configuration in which an X-axis electrode and a Y-axis electrode orthogonal to the X-axis electrode are arranged through an insulator. As a specific embodiment, an embodiment in which the X electrode and the Y electrode are formed on different surfaces on one substrate, the mode in which the X electrode, the insulator layer and the Y electrode are formed in this order on one substrate, And the Y electrode is formed on another substrate (in this embodiment, the two substrates are combined with each other in the basic configuration described above). Further, the configuration of the capacitive touch panel is known, and in the present embodiment, the known technology can be applied without limitation.

Example

Hereinafter, the present disclosure will be described in more detail by way of examples and comparative examples. The materials, the amounts used, the ratios, the processing contents, the processing procedures, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present disclosure. Therefore, the scope of the present disclosure is not to be construed as limited by the specific examples described below.

In addition, "parts" and "ppm" are on a mass basis unless otherwise specified.

[Example 1]

<Synthesis of raw material polyester>

(Raw polyester 1)

As shown in the following, terephthalic acid and ethylene glycol were directly reacted to distill off the water, followed by esterification, and polycondensation was carried out under reduced pressure to obtain a raw polyester 1 ( Sb catalyst system PET).

(1) Esterification reaction

4.7 tons of high purity terephthalic acid and 1.8 tons of ethylene glycol were mixed for 90 minutes to form a slurry and continuously fed to the first esterification reactor at a flow rate of 3800 kg / h. Further, an ethylene glycol solution of antimony trioxide was continuously supplied, and the reaction was carried out at a temperature of 250 DEG C in the reactor with stirring for an average residence time of about 4.3 hours. At this time, antimony trioxide was continuously added so that the amount of Sb added was 150 ppm in terms of element.

The reaction product was transferred to a second esterification reaction tank and reacted with stirring at an average residence time of 1.2 hours at a temperature of 250 캜 in the reaction tank. In the second esterification reaction tank, an ethylene glycol solution of magnesium acetate and an ethylene glycol solution of trimethyl phosphate were continuously supplied so that the Mg addition amount and the P addition amount were 65 ppm and 35 ppm, respectively, in terms of element.

(2) Polycondensation reaction

The esterification reaction product obtained above was continuously supplied to the first polycondensation reaction tank and subjected to polycondensation at an average residence time of about 1.8 hours at a reaction temperature of 270 ° C and a pressure of 20 torr (2.67 × 10 ^-3 MPa) .

The reaction was carried out in the second polycondensation reaction tank under the conditions of a temperature of 276 DEG C in the reaction tank and a residence time of about 1.2 hours at a pressure of 5 torr (6.67 x 10 &lt; ^-4 &gt; .

(Polycondensation) was carried out in the reaction tank at a temperature of 278 DEG C in the reaction vessel at a pressure of 1.5 torr (2.0 x 10 &lt; ^-4 &gt; MPa) and a residence time of 1.5 hours, To obtain a reaction product (polyethylene terephthalate; PET).

Next, the obtained reaction product was discharged into cold water in a strand shape, and immediately cut to produce a polyester pellet "cross-section: about 4 mm long diameter, about 2 mm long, about 3 mm long.

The obtained polyester had IV = 0.63. This polyester was used as raw polyester 1.

&Lt; Production of polyester film >

- Film forming process -

The raw polyester 1 was dried to a moisture content of 20 ppm or less and then charged into a hopper 1 of a single screw extruder 1 having a diameter of 50 mm. The raw material polyester 1 was melted at 300 캜 and extruded from a die through a gear pump and a filter (hole diameter 20 탆) according to the following extrusion conditions.

The molten resin was extruded from the die at a pressure fluctuation of 1% and a molten resin temperature distribution of 2%. Specifically, the back pressure was 1% of the average pressure in the barrel of the extruder, and the pipe temperature of the extruder was set at 2% higher than the average temperature in the barrel of the extruder.

The molten resin extruded from the die was extruded on a cooled cast drum set at a temperature of 25 占 폚 and was brought into close contact with the cooled cast drum using an electrostatic application method. And peeled off using a peeling roll opposed to the cooling cast drum to obtain an unstretched polyester film 1.

- Formation of this adhesive layer -

The following compounds were mixed in the proportions shown below to prepare a coating liquid H1 for forming the adhesive layer.

(Coating liquid H1 for forming this adhesive layer)

Polyester Resin: (IC) 60 parts by mass

Acrylic resin: (II) 25 parts by mass

Melamine compound: (VIB) 10 parts by mass

Particles: (VII) 5 parts by mass

Details of the compound used for forming this adhesive layer are shown below.

Polyester Resin: (IC)

A sulfonic acid-based water dispersion product of a polyester resin copolymerized with a monomer having the following composition

Monomer Composition: (Acid component) Terephthalic acid / isophthalic acid / 5-sodium sulfoisophthalic acid // (diol component) Ethylene glycol / 1,4-butanediol / diethylene glycol = 56/40/4 // 70/20/10 (mol%)

Acrylic resin: (II)

A water dispersion of an acrylic resin polymerized with a monomer having the following composition

(Emulsifier: anionic surfactant) of ethyl acrylate / n-butyl acrylate / methyl methacrylate / N-methylol acrylamide / acrylic acid = 65/21/10/2/2 (mass%

Melamine compound: (VIB) Hexamethoxymethyl melamine

Particles: (VII) silica sol having an average particle size of 150 nm (average particle diameter means the average primary particle size, that is, the average value of the primary particle size)

- Application of this adhesive layer to one side of the polyester film -

The coating liquid H1 for forming the adhesive layer was coated on one side of the unstretched polyester film 1 by using a wire bar while adjusting the coating film thickness after stretching to 65 nm by a bar coating method using a wire bar.

- transverse stretching process -

The unstretched polyester film 1 was led to a tenter (transverse stretching machine) and transversely stretched under the following method while grasping the end portion of the film with a clip.

(Preheating section)

And heated by hot air so that the surface temperature at the time of stretching became 89 占 폚.

The surface temperature at the time of stretching was measured by a radiation thermometer (Hayashi Denken Co., Ltd., product number: RT61-2, emissivity 0.95) at the point of starting the stretching at the central portion in the film width direction did.

(Extension section)

The pre-heated unstretched polyester film 1 was transversely stretched in the transverse direction (TD) using a tenter under the following conditions while heating with hot air.

Further, the surface temperature at each stretching magnification time point is measured by a radiation thermometer (Hayashi Denken Co., Ltd., product number: RT61-2, emissivity 0.95) at the central portion in the film width direction at each stretch magnification did.

<Condition>

· Horizontal stretching ratio: 4.1 times

· Surface temperature at 2 times stretching: 90 ° C

Surface temperature at 3 times stretching: 94 ° C

Surface temperature at the end of stretching: 95 占 폚

(Open-top and thermal relaxation department)

Next, hot air from the upper and lower directions was applied to the film from the hot air jetting nozzle to the film, and heat setting and heat relaxation treatment were carried out while controlling the surface temperature of the polyester film to the following range.

<Condition>

· Maximum reaching surface temperature (heat setting temperature): 185 ℃

· Thermal relaxation rate: MD 4%, TD 1.5%

(Cooling section)

Next, the film was cooled by applying cold air from the upper and lower directions to the film from the cold air jetting nozzle. The film was cooled so that the surface temperature when the film was released from the clips of the tenter was 40 占 폚.

The surface temperature was measured by a radiation thermometer (Hayashi Denken Co., Ltd., product number: RT61-2, emissivity 0.95) at the central portion in the film width direction.

(Number of times of film)

After cooling and opening of the film from the clip, both ends of the polyester film were trimmed by 20 cm. The film width after trimming was 2 m. Thereafter, extrusion processing (knurling) was performed at both ends at a width of 10 mm, and a film having a tension of 18 kg / m and a length of 10,000 m was wound in a roll form.

Thus, a polyester film of Example 1 having a thickness of 200 mu m wound in a roll form was produced.

[Examples 2 to 11, 13 and 14, Comparative Examples 1 to 3 and 5]

The polyester film of each of Examples and Comparative Examples was produced in the same manner as in Example 1 except that the conditions of the transverse stretching step, the adhesive layer and the hard coat layer were changed as shown in Table 1, respectively, .

[Example 12, Comparative Example 4]

A polyester film of Example 12 was produced in the same manner as in Example 1 except that this adhesive layer was not provided.

The polyester film of Comparative Example 4 was produced in the same manner as in Example 1 except that the condition of the transverse stretching process and the film thickness were changed as shown in the following Table 1 and the adhesive layer was not further provided. In Comparative Example 4, a polyester film was produced by a similar method based on the description of Example 2 of Japanese Laid-Open Patent Publication No. 2012-230390.

[Film measurement result]

The following properties of the films obtained in the respective Examples were measured. The measurement results are shown in Table 1 below.

<Thickness>

The thicknesses of the polyester films obtained in the respective Examples and Comparative Examples were determined as follows.

The polyester film of each of the Examples and Comparative Examples was sampled at regular intervals of 50 m in 0.5 m lengthwise direction (longitudinal direction) using a contact type film thickness meter (manufactured by Anritsu Corporation) 50 points were sampled at uniform intervals (50 equal parts in the width direction) across the entire width of the film in the width direction (direction orthogonal to the longitudinal direction), and then the thicknesses of these 100 points were measured. The average thickness of these 100 points was determined to be the thickness of the polyester film.

&Lt; Re, Rth, Re / Rth Ratio >

Re and Rth were determined for the films obtained in the respective examples by the above-described method. Re / Rth ratio was calculated from Re and Rth obtained.

<Shear vertical stress and shear yield stress>

Using the SAICAS-NN type (manufactured by Dai-ichi K.K.), the polyester film of each of the examples and comparative examples thus obtained was subjected to the above-mentioned method Lt; / RTI &gt;

From the obtained measured values, the average value of the normal vertical stress A in the slow axis direction in the surface layer of 1 mu m and the normal vertical stress B in the direction perpendicular to the slow axis direction in the film plane was calculated. TD is the slow axis direction of the film, and MD is the fast axis direction of the film.

[Production of hard coat film]

A coating liquid for forming a hard coat layer having the following composition was prepared.

Cyclomer M100: 3,4-epoxycyclohexylmethyl methacrylate (Daicel Co., Ltd.) 40 parts by mass

DPHA: KAYARD DPHA (manufactured by Nippon Kayaku Co., Ltd.) 55.4 parts by mass

Irgacure 127: alkylphenon-based photopolymerization initiator (BASF) 2.5 parts by mass

Irgacure290: a sulfonium salt cationic polymerization initiator (BASF) 2.0 parts by mass

· Wind irregularity inhibitor FP-1: Fluorine compound of the following structure 0.1 parts by mass

Solvent 1 MEK 100 parts by mass

Solvent 2 MIBK 50 parts by mass

[Chemical Formula 14]

The uniaxially stretched polyester film of each of the examples and comparative examples wound in roll form was unwound and, as a post-process, the coating liquid for forming the hard coat layer was applied by the following method.

The coating liquid for forming the hard coat layer was applied on one side of the film (when the adhesive layer was provided, on the side of the adhesive layer) by a die coating method using a slot die described in Example 1 of Japanese Patent Laid-Open Publication No. 2006-122889 at a conveying speed of 30 m / min . After drying at 60 占 폚 for 150 seconds, an illuminance of 400 mW / cm &lt; ² &gt; and an irradiation dose of 500 mJ / cm &lt; ² &gt; (Hard coat layer) was cured and wound up.

<Thickness of Hard Coat Layer>

In the case of using the polyester film obtained in Examples or Comparative Examples other than Example 9, when the thickness of the hard coat layer was 22 占 퐉 and the polyester film obtained in Example 9 was used, the thickness of the hard coat layer was 5 占 퐉 .

The film thickness of the hard coat layer was calculated by measuring the film thickness of the hard coat film produced by the contact type film thickness regulator and subtracting the thickness of the polyester film measured in the same manner.

[evaluation]

The hard coat films obtained in the respective Examples and Comparative Examples were subjected to the following evaluations. The evaluation results are shown in Table 1 below.

&Lt; Evaluation of punching &

The hard coat film was subjected to punching 10 times, and the cracking / peeling state of the hard coat of the punching section was evaluated according to the following criteria.

A: No cracking / peeling at all

B: Cracking / peeling only occurs once

C: Cracking / peeling occurs only 2 or 3 times

D: Cracking / peeling occurs more than 4 times

&Lt; Evaluation of surface deformation &

The surface of the hard coat film (on the side of the hard coat layer) was depressed with a stylus at a force of 10 N / mm &lt; ^{2 &gt;} . The recesses were observed and evaluated according to the following criteria.

A: No recesses at all

B: The recess is not visible to the naked eye, but can be recognized by observation under a microscope

C: The recess is slightly visible to the naked eye

D: The concave part can be clearly seen with the naked eye

<Evaluation of visibility>

The hard coat film was placed between the polarizing plates provided in Cross Nicol so that the orientation angle thereof was inclined at an angle of 45 占 with respect to the absorption axis of the polarizing plate and the visibility of the LED backlight was evaluated by the following criteria.

A: I can not see rainbow irregularities at all

B: Rainbow irregularities are hardly visible

C: Rainbow unevenness is slightly visible, but acceptable

D: Rainbow unevenness is strong

[Table 1]

The meanings of symbols in Table 1 are as follows.

DPHA: KAYARD DPHA (manufactured by Nippon Kayaku Co., Ltd.)

3,4-epoxy CHMA: 3,4-epoxycyclohexylmethyl acrylate

3,4-Epoxy CHMM: 3,4-epoxycyclohexylmethyl methacrylate

IRG127: Irgacure127 (alkylphenon-based photopolymerization initiator, BASF)

IRG290: Irgacure290 (a sulfonium salt-based cationic polymerization initiator, manufactured by BASF)

RS-90: (antifouling agent, manufactured by DIC Corporation)

As is clear from Table 1, the hard coat films of the Examples were suppressed from cracking, peeling and occurrence of recesses in the hard coat layer, as compared with the hard coat films of the Comparative Examples.

The disclosure of Japanese Patent Application No. 2016-026351 filed on February 15, 2016 is incorporated herein by reference in its entirety.

All publications, patent applications, and technical specifications described in this specification are herein incorporated by reference to the same extent as if each individual document, patent application, do.

10 cutting blades
12 Polyester film
20 clip (holding member)

Claims (17)

A thickness of 40 to 500 占 퐉, a normal frontal section stress A in the longitudinal direction of the surface layer of 1 占 퐉 and an average value of the longitudinal section normal stress B in the direction orthogonal to the longitudinal axis direction in the film surface of 30 to 100 MPa . The method according to claim 1,
A polyester film for a substrate film of a hard coat film. The method according to claim 1 or 2,
Polyester film which is uniaxially oriented polyester film. The method according to any one of claims 1 to 3,
Wherein the retardation Re in the film plane at a measurement wavelength of 589 nm of the polyester film is 4000 to 50000 nm. The method according to any one of claims 1 to 4,
Wherein the average value of the shear yield stress in the slow axis direction at the surface layer of 1 占 퐉 of the polyester film and the shear yield stress in the direction perpendicular to the slow axis direction in the film plane is 20 to 60 MPa. The method according to any one of claims 1 to 5,
And a ratio of the shear vertical stress A to the shear vertical stress B is 1.1 to 2.0. The method according to any one of claims 1 to 6,
Wherein the ratio of the retardation Re in the film plane to the retardation Rth in the film thickness direction at a measurement wavelength of 589 nm of the polyester film is 0.6 to 1.2. A base film comprising the polyester film according to any one of claims 1 to 7,
And a hard coat layer laminated on at least one side of the base film. The method of claim 8,
Wherein the hard coat layer has a thickness of 5 m or more. The method according to claim 8 or 9,
Wherein the hard coat layer comprises:
At least the structure derived from a), the structure derived from b), the structure derived from c) and d)
Wherein the hard coat layer comprises 15 to 70 mass% of the structure derived from the following a), 25 to 80 mass% of the structure derived from the following (b), and c) 0.1 to 10 mass%, and d) 0.1 to 10 mass%.
a) a compound having a group containing one alicyclic epoxy group and one ethylenically unsaturated double bond in the molecule and having a molecular weight of 300 or less
b) a compound having a group containing three or more ethylenically unsaturated double bonds in the molecule
c) a radical polymerization initiator
d) cationic polymerization initiator An image display device comprising an image display element and the hard coat film according to any one of claims 8 to 10, wherein the hard coat film is disposed on the outermost surface. A touch panel comprising the hard coat film according to any one of claims 8 to 10, wherein the hard coat film is disposed on the outermost surface. By using a transverse stretching apparatus having a plurality of clips which run along a pair of rails provided on both sides of the film carrying path,
A preheating step of preheating an unoriented or vertically stretched polyester film at a heating rate of 600 DEG C / min or less,
Transversely stretching the film in a direction orthogonal to the film transport path in a state that both edges of the preheated polyester film are held by the plurality of clips; The surface temperature at the start of the transverse stretching is controlled to be not less than 80 ° C and not more than 95 ° C and the surface temperature at the end of the transverse stretching is controlled to be not less than 90 ° C and not more than 105 ° C, Is controlled to be in the range of 3.3 times or more and 4.8 times or less,
And a heat fixation step of thermally fixing the polyester film after the transverse stretching step by heating to a maximum temperature in the transverse stretching apparatus,
A method for producing a polyester film having a thickness of 40 to 500 占 퐉. 14. The method of claim 13,
In the transverse stretching step, the surface temperature is gradually raised at a heating rate of 60 DEG C / min or less to adjust the surface temperature to 80 DEG C or more and 92 DEG C or less when the transverse stretching magnification is in the range of 1 to 2 times in,
The surface temperature when the transverse stretch magnification is in the range of 2 times or more and less than 3 times is set to 85 deg. C or more and 97 deg. C or less, and
Wherein the surface temperature when the transverse stretching magnification is in the range of 3 times or more is controlled to 90 占 폚 or more and 102 占 폚 or less. The method according to claim 13 or 14,
The rate of temperature rise of the surface temperature of the polyester film from the end of the transverse drawing step until reaching the maximum temperature in the heat setting step is controlled to be not more than 1000 ° C / min,
Wherein the polyester film has a maximum surface temperature of 130 占 폚 or higher and 230 占 폚 or lower in the heat fixation step to control the time when the surface temperature of the polyester film exceeds 130 占 폚 to 180 seconds or less &Lt; / RTI &gt; The method according to any one of claims 13 to 15,
Further comprising a thermal relaxation step of heating the polyester film after the heat setting step and reducing the length of the polyester film at least in the transverse direction. A process for producing a polyester film according to any one of claims 13 to 16,
And a step of laminating a hard coat layer on at least one side of the polyester film.

Images