JP2000043142A - Base film for glare-protecting film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject base film based on polyethylene-2,-6-naphthalene dicarboxylate and excellent in transparency and deformation resistance. SOLUTION: A base film comprises a biaxially stretched film based on polyethylene-2,6-naphthalene dicarboxylate and the haze value thereof is 5% or less and the deformation resistance thereof satisfies P/h2>=0.536 (h<=0.1 t) wherein P is load (gf) applied to the surface of the film by using an indenter; h is the depth (μm) pushed in by the indenter and t is the thickness (μm) of the base film}.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base film for an antiglare film, and more particularly, to a polyethylene film.
The present invention relates to a base film for an antiglare film having excellent transparency and excellent deformation resistance, comprising 2,6-naphthalenedicarboxylate as a main component.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of preventing danger in the event of a disaster or accident, a flexible organic thin film is bonded to at least one surface of a glass such as a window glass, a show window, a glass case, or a glass of various physical and chemical instruments. Attempts have been made to prevent the scattering of water, which has already been put to practical use in some fields.

As such an organic thin film for preventing glass scattering, a biaxially stretched polyethylene terephthalate (hereinafter sometimes abbreviated as PET) film is used at present, and a typical use form thereof is as follows. .

That is, a pressure-sensitive adhesive layer is applied to a biaxially stretched polyethylene terephthalate film having a certain degree of strength, and a separator is laminated thereon. The separator is peeled off at the time of use to bring the pressure-sensitive adhesive layer into close contact with the glass surface. This prevents the glass from scattering at the time of breakage.

[0005] Further, a property that is more important than the glass scattering prevention effect recently is the antiglare effect, and the state of light reflection on the film surface is controlled by a method such as laminating a thin metal film such as aluminum. It has become commonplace.

[0006] A polyethylene terephthalate film used as a base film for effectively exhibiting such an antiglare effect and a glass scattering prevention effect requires some properties. For example, they are excellent in transparency and adhesiveness, high in mechanical strength and low in heat shrinkage, and are also indispensable items for practical handling.

The demand for biaxially oriented polyethylene terephthalate film has been steadily increasing since it can satisfy a considerable part of these required properties, but recently, in terms of strength, heat shrinkage, film scratch resistance and the like. Higher properties are required, and biaxially stretched polyethylene terephthalate film has insufficient performance especially as a film to be bonded to image display panels such as televisions and monitors, such as cathode ray tubes and plasma displays. Has become apparent.

[0008]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to solve the above-mentioned problems of the prior art, and as a result, have found that a biaxially stretched film containing polyethylene-2,6-naphthalenedicarboxylate as a main component. By having a haze value of the film of 5% or less and an index indicating the difficulty of deformation of the film being a certain value or more, the glass has the same glass scattering prevention effect as a PET film, and has excellent transparency.
The inventors have found that a base film for an antiglare film having excellent deformation resistance can be provided, and have reached the present invention.

[0009]

The object of the present invention is to provide:
An anti-glare film comprising a biaxially stretched film containing polyethylene-2,6-naphthalenedicarboxylate as a main component, wherein the film has a haze value of 5% or less and the film has a deformation resistance satisfying the following formula. The solution is achieved by a film base film.

[0010]

P / h ² ≧ 0.536 (h ≦ 0.1t) (where P is the load (gf) applied to the film surface using an indenter, and h is the depth pushed by the indenter. (Μ
m) and t represent the thickness (μm) of the base film)

[Polyethylene-2,6-naphthalenedicarboxylate] In the present invention, the base film for an anti-glare film comprises polyethylene-2,6-naphthalenedicarboxylate as a main component.

In this polyethylene-2,6-naphthalenedicarboxylate, the main dicarboxylic acid component is naphthalenedicarboxylic acid, and the main glycol component is
Ethylene glycol. Here, examples of the naphthalenedicarboxylic acid include 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, and the like. Acids are preferred. Mainly means that at least 80 mol% of all repeating units in the constituent components of the polymer which is a component of the film of the present invention.
Is ethylene-2,6-naphthalenedicarboxylate. More preferably, it is 90 mol%.

The polymer constituting the film of the present invention may be composed of a copolymer or a mixture containing polyethylene-2,6-naphthalenedicarboxylate as a main component. It is not less than 80 mol% of the repeating unit, and does not extremely lose the original properties of the polyethylene-2,6-naphthalenedicarboxylate film, and can be processed at a high temperature (for example, by sputtering at the time of applying an antiglare layer). It is sufficient that excellent heat resistance, that is, dimensional stability and flatness can be ensured.

In the case of a copolymer, as a copolymerization component constituting a copolymer other than the main component ethylene-2,6-naphthalenedicarboxylate, 2
Compounds having two ester-forming functional groups can be used, such as oxalic acid, adipic acid, phthalic acid, sebacic acid, dodecanedicarboxylic acid,
Such as isophthalic acid, terephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, phenylindanedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, tetralindicarboxylic acid, decalindicarboxylic acid, diphenyletherdicarboxylic acid, etc. Dicarboxylic acids; oxycarboxylic acids such as p-oxybenzoic acid and p-oxyethoxybenzoic acid; or ethylene of propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane methylene glycol, neopentyl glycol, bisphenolsulfone Preferred are oxide adducts, ethylene oxide adducts of bisphenol A, and dihydric alcohols such as diethylene glycol and polyethylene oxide glycol. Can be used.

These compounds can be used alone or in combination of two or more. Of these, isophthalic acid, terephthalic acid,
The ethylene oxide adduct of 4'-diphenyldicarboxylic acid, 2,7-naphthalenedicarboxylic acid, p-oxybenzoic acid, and the glycol component is trimethylene glycol, hexamethylene glycol, neopentyl glycol, and bisphenolsulfone.

The polyethylene-2,6-naphthalenedicarboxylate is obtained by blocking some or all of the terminal hydroxyl groups and / or carboxyl groups with a monofunctional compound such as benzoic acid or methoxypolyalkylene glycol. Alternatively, the copolymer may be a copolymer of a very small amount of an ester-forming compound having three or more functions such as glycerin and pentaerythritol within a range where a substantially linear polymer can be obtained.

Further, the base film for an antiglare film of the present invention may be composed of a mixture of an organic polymer in addition to the main component polyethylene-2,6-naphthalenedicarboxylate.

As such organic polymers, polyethylene terephthalate, polyethylene isophthalate, polytrimethylene terephthalate, polyethylene-4,4'-tetramethylenediphenyldicarboxylate, polyethylene-2,7-naphthalenedicarboxylate, polytrimethylene-2 , 6-naphthalenedicarboxylate, polyneopenthylene-2,6-naphthalenedicarboxylate, poly (bis (4-ethyleneoxyphenyl) sulfone) -2,6-naphthalenedicarboxylate, and the like. Among them, polyethylene isophthalate, polytrimethylene terephthalate, polytrimethylene-2,6-naphthalenedicarboxylate, poly (bis (4-ethyleneoxyphenyl) sulfone)-
2,6-Naphthalenedicarboxylate is preferred.

In the base film for an antiglare film of the present invention, not only one kind but also two or more kinds of these organic polymers may be used in an amount of 20 mol%, preferably 10 mol%, corresponding to the repeating unit of the polymer. , 6-naphthalenedicarboxylate. The production of such a mixture can be carried out by a generally known method for producing a polyester composition.

[Haze] The base film for an antiglare film of the present invention has a haze value of 5% or less. If the haze value of the film exceeds 5%, the film becomes cloudy and the transparency becomes insufficient, which is not preferable. The haze value of the film is preferably 3
% Or less. The lower limit of this value is 0.1%.

[Film Deformation Resistance] In the base film for an antiglare film of the present invention, the value (P / h ² ) which is an index of the difficulty of deformation of the film is represented by the following formula:

[0022]

P / h ² ≧ 0.536 (h ≦ 0.1t) (where P is the load (gf) applied to the film surface using an indenter, and h is the depth pushed by the indenter. (Μ
m) and t represent the thickness (μm) of the base film).

The above equation shows the relationship between the amount of load applied to the film surface using the indenter and the amount of buckling of the film. The value (P / h ² ) calculated from this relational expression is It indicates the deformability, that is, the resistance to deformation when an external force is applied to the film surface. Increasing this value improves the scratch resistance of the film. When this value is less than 0.536, when an impact is applied within a range in which the glass is not broken after bonding the glass, the deformation of the base film becomes large, and the antiglare layer or the hard film applied on the base film is hardened. It causes peeling at the interface with the coat layer or the like. A more preferred range of the P / h ² value is 0.550 or more. Also P /
The upper limit of the h ² value is about 0.85.

[Intrinsic Viscosity] The base film for an antiglare film of the present invention has an intrinsic viscosity of 0.40 dl / g or more and 0.90 or more.
dl / g or less, more preferably 0.43 dl / g or more and 0.80 dl / g or less.

When the intrinsic viscosity is less than 0.40 dl / g, the film becomes brittle, and when the film is cut into a predetermined size, burrs are generated on the end face, and sometimes cracks are generated from a part of the burrs, resulting in poor product yield. Become.

The intrinsic viscosity of the film is 0.90 dl.
If it exceeds / g, the intrinsic viscosity of the PEN polymer needs to be considerably increased, and it takes a long time for polymerization in a usual synthesis method, resulting in poor productivity. In addition, in order to perform a special polymerization method (such as solid-phase polymerization), dedicated equipment is required, so that the production cost increases.

[Young's modulus] The sum of the Young's modulus in the machine direction (MD) and the transverse direction (TD) of the base film for an antiglare film of the present invention is preferably at least 900 kg / mm ^2, The difference in the Young's modulus in the direction (TD) (| Young's modulus _MD -Young's modulus _TD |) is preferably 100 kg / mm ² or less.

The longitudinal direction (MD) and the lateral direction (T
If the sum of the Young's modulus of D) is less than 900 kg / mm ² , the glass scattering prevention performance of the film becomes insufficient. More preferably, the sum of Young's modulus is 1000 kg / mm ² or more and 1600.
kg / mm ² or less.

The difference between the Young's modulus in the longitudinal direction (MD) and the transverse direction (TD) (| Young's modulus _MD -Young's modulus _TD |) is 100.
If it exceeds kg / mm ² , the film tends to tear in one direction, and the glass scattering prevention performance (as a surface) deteriorates. A more preferable difference in Young's modulus (| Young's modulus _MD -Young's modulus _TD |) is 0 kg / mm ² or more and 50 kg / mm ² or less.

[Plane Orientation Coefficient (ns)] The base film for an antiglare film of the present invention has a plane orientation coefficient (ns) of 0.25.
It is preferably 0 or more, more preferably 0.2
55 or more. When the plane orientation coefficient (ns) is less than 0.250, unevenness in thickness of the film becomes worse, and when the film is bonded to glass such as an image display panel of an image display device, light transmission becomes uneven.

[Surface Roughness (Ra)] The base film for an antiglare film of the present invention has a surface roughness (Ra) of 10 n.
m, more preferably 7 nm or less.
It is as follows. If the surface roughness (Ra) exceeds 10 nm, surface reflection due to unevenness of the surface becomes strong, and the transparency of the film deteriorates.

[Thickness] The base film for an antiglare film of the present invention preferably has a thickness in the range of 50 to 350 μm, more preferably 75 to 250 μm.
Particularly preferably, it is 100 to 200 μm. Thickness 50
When it is less than μm, the bending rigidity of the film is insufficient and workability deteriorates when an adhesive layer or the like is provided on one side of the film and the film is bonded to glass such as an image display device. On the other hand, when the thickness exceeds 350 μm, it becomes difficult to bond the glass to the glass.

[Stiffness] The base film for an antiglare film of the present invention preferably has a stiffness of 2.0 g or more, more preferably 2.5 g or more.
When the stiffness of the film is less than 2.0 g, the bending stiffness is insufficient, so that the workability is deteriorated when the film is bonded to glass such as an image display device via an adhesive.

[Additives] The base film for an antiglare film of the present invention may contain additives such as stabilizers, lubricants and flame retardants.

In order to impart slipperiness to the film, it is preferable to contain a small proportion of inert fine particles.

Examples of such inert fine particles include spherical silica, porous silica, calcium carbonate, alumina,
Examples include inorganic particles such as titanium dioxide, kaolin clay, barium sulfate, and zeolite, or organic particles such as silicon resin particles and crosslinked polystyrene particles.

In the case of inorganic particles, it is preferable to use a synthetic product rather than a natural product because the particle size is uniform.
Inorganic particles of any crystal morphology, hardness, specific gravity, and color can be used.

The above-mentioned inert fine particles have an average particle size of 0.05.
Μ5.0 μm, preferably 0.1-5.0 μm.
More preferably, it is 3.0 μm.

The content of the inert fine particles is preferably from 0.001 to 0.3% by weight, more preferably from 0.003 to 0.2% by weight, based on the weight of the film. Particularly preferred is 0.1% by weight.

Further, the inert fine particles to be added to the film may be a single component selected from those exemplified above, or may be a multi-component containing two or more than three components.

The addition time of the inert fine particles is not particularly limited as long as it is a stage before the polyethylene-2,6-naphthalenedicarboxylate is formed. For example, the inert fine particles may be added at the polymerization stage. May be added at this time.

[Specific production conditions] The base film for an antiglare film of the present invention can be produced by biaxially stretching an unstretched film obtained by a usual method and heat-setting it in a specific temperature range. it can. For example, if the unstretched film is
g to (Tg + 60) (° C) or less [Tg is the glass transition temperature of the film polymer ° C].
As described above, a desired film can be obtained by heat setting at a temperature of (Tg + 135) ° C. or lower for 1 to 100 seconds.

The stretching can be performed by a generally used method, for example, a method using a roll or a method using a stenter.
Moreover, you may extend | stretch sequentially in a longitudinal direction and a horizontal direction.

Further, after the biaxial stretching, the film may be stretched again in the vertical or horizontal direction, or in the vertical or horizontal direction.

To obtain the film of the present invention,
For example, in particular, the ratio of the longitudinal stretching ratio to the transverse stretching ratio (longitudinal / lateral) is 0.85 to 1.15, and the heat setting temperature is (Tg +
60) C. or higher and (Tg + 110) C. or lower,
It can be manufactured more advantageously.

In particular, since the heat setting temperature affects the transparency, deformation resistance and workability of the film, it is preferable to satisfy the above temperature range. This heat setting temperature is observed as an endothermic peak other than the melting peak by analyzing the formed film using a differential scanning calorimeter (DSC). A film can be obtained.

The method for producing a film of the present invention is not limited to these as long as the film satisfies the above-mentioned characteristics.

In the present invention, it is preferable that an adhesive layer is provided on one surface of the biaxially stretched film and the film is bonded to glass for use.

The pressure-sensitive adhesive layer may be provided by using a conventionally used or known pressure-sensitive adhesive or adhesive. The layer is preferably provided by a coating method or the like. Further, a release film is preferably provided on the pressure-sensitive adhesive layer for the purpose of protecting the layer. The release film is peeled before use, and then the pressure-sensitive adhesive layer is brought into contact with the glass to be bonded, thereby improving workability.

[0050]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless the gist is changed. The measuring methods and definitions of various physical properties and characteristics in the examples and comparative examples are as follows.

(1) Calculation of Component Amounts of Ethylene-2,6-Naphthalenedicarboxylate (Mole Ratio of Main Component, Copolymer Component) A film sample was measured with a solvent (CDCl ₃ : CF ₃ COO).
(D = 1: 1), and ¹ H-NMR measurement is carried out, and it is calculated by the integration ratio of each obtained signal.

(2) Deformation resistance of film Micro compression tester (MCTM-20 manufactured by Shimadzu Corporation)
1), a triangular pyramid-shaped indenter (indenter shape: triangular pyramid (α
= Β = γ = 115 °)) and the depth of penetration of the indenter into the film at this time (this depth is set to 10% or less of the thickness of the measured film).
｛Is determined, and the (P / h ² ) value indicating the deformation resistance obtained from the relationship between the applied load and the penetration depth is calculated by the following equation.

[0053]

P / h ² ≧ 0.536 (h ≦ 0.1t) (where P is the load (gf) applied to the film surface using an indenter, and h is the depth pushed by the indenter. (Μ
m) and t represent the thickness (μm) of the base film).

(3) Plane orientation coefficient (ns) Using an Abbe refractometer (manufactured by Atago Co., Ltd.), 2
Using a Na-D line at 5 ° C, the longitudinal direction (M
D), transverse direction (TD) and film thickness direction (Z)
(N _MD , n _TD , n _z ) are determined, and the film sample is measured on both front and back sides, and ns for each of the front and back sides is calculated by the following equation. Ns calculated for each side
Is defined as the plane orientation coefficient (ns).

[0055]

Equation 5] _{ns = {(n MD + n} TD) / 2} -n z

(4) Young's modulus The sample was cut into a width of 10 mm and a length of 150 mm.
Set to 00 mm, pulling speed 10 mm / min, chart speed 5
It is pulled with an Instron type universal tensile tester at 00 mm / min. Load obtained by measuring MD and TD respectively-
The Young's modulus is calculated from the tangent line at the top of the elongation curve.

(5) Intrinsic viscosity This is a value (unit: dl / g) measured at 25 ° C. using o-chlorophenol as a solvent.

(6) Surface Roughness (Ra) Both the front and back surfaces of the film are measured by a surface roughness meter (Surfcom 111A, manufactured by Tokyo Seimitsu Co., Ltd.), and the average value is calculated and expressed in nm to obtain the surface roughness.

(7) Haze value According to the method of JIS K-6714, the total haze value per film is measured by a commercially available haze meter.

(8) Stiffness Samples (width 3 mm, loop length 100 mm) were cut out in each of the main orientation direction and the direction perpendicular to the main orientation direction, and a loop stiffness tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.) was cut out from these samples. Then, the buckling strength of the loop is measured by n = 5 each, and an average value is calculated as stiffness in each direction. The average value of the calculated stiffness in the main orientation direction and the direction perpendicular to the main orientation direction is defined as stiffness.

[Example 1] 100 parts of dimethyl 2,6-naphthalenedicarboxylate and 60 parts of ethylene glycol were used as transesterification catalysts using 0.03 part of manganese acetate tetrahydrate, and a lubricant having an average particle diameter of 0.3 µm was used. After adding 0.002 parts of silica particles and performing a transesterification reaction according to a conventional method, 0.023 parts of trimethyl phosphate was added to substantially terminate the transesterification reaction.

Then, 0.024 part of antimony trioxide was added, and a polymerization reaction was carried out by a conventional method at a high temperature and a high vacuum to obtain polyethylene-2, having an intrinsic viscosity of 0.60 dl / g.
6-naphthalenedicarboxylate (PEN Tg = 1
21 ° C.). This PEN containing silica particles was melt-extruded from a die slit, and then cooled and solidified on a casting drum to prepare an unstretched film.

The unstretched film was successively biaxially stretched 3.8 times in the machine direction (machine direction) and 4.0 times in the transverse direction (width direction) and heat-set at a temperature of (Tg + 95) ° C. Thickness 1
A 50 μm biaxially oriented film was obtained. The biaxially-stretched film was treated at both ends so that the height of the embossment was 25 μm, and then the biaxially-stretched film was wound around a roll. Table 1 shows the physical properties and evaluation results of the obtained biaxially stretched film.

Example 2 A film was formed in the same manner as in Example 1 except that the heat setting temperature was (Tg + 110) ° C. Table 1 shows the results.

[Embodiment 3] The vertical direction (M
A film was formed in the same manner except that the stretching ratio in D) was 4.2 times and the stretching ratio in the transverse direction (TD) was 4.3 times. Table 1 shows the results.

[Example 4] In Example 1, the amount of silica particles having an average particle diameter of 0.3 µm added as a lubricant was 0.003.
The polymerization was carried out in the same manner as in Example 1 except that the polyethylene-2,6-naphthalenedicarboxylate having an intrinsic viscosity of 0.60 dl / g was obtained. Table 1 shows the film forming conditions and results.

Example 5 A film was formed using polyethylene-2,6-naphthalenedicarboxylate having an intrinsic viscosity of 0.52 dl / g in Example 1. Table 1 shows the film forming conditions and results.

[Embodiment 6] In Embodiment 1, the vertical direction (M
A film was formed in the same manner except that the stretching ratio in D) was 3.0 times and the stretching ratio in the transverse direction (TD) was 3.1 times. Table 1 shows the results.

[Embodiment 7] In Embodiment 1, the vertical direction (M
A film was formed in the same manner except that the stretching ratio in D) was 3.6 times and the stretching ratio in the transverse direction (TD) was 4.2 times. Table 1 shows the results.

Example 8 Manganese acetate tetrahydrate 0.03 was prepared using 89 parts of dimethyl 2,6-naphthalenedicarboxylate, 11 parts of isophthalic acid (may be abbreviated as IA) and 60 parts of ethylene glycol as a transesterification catalyst. Of silica particles having an average particle diameter of 0.3 μm as a lubricant.
After adding 002 parts, and performing a transesterification reaction according to a conventional method, 0.023 parts of trimethyl phosphate was added to substantially terminate the transesterification reaction.

Then, 0.024 parts of antimony trioxide was added, and a polymerization reaction was carried out by a conventional method at a high temperature and a high vacuum to obtain a polyethylene-based polymer having an intrinsic viscosity of 0.60 dl / g.
2,6-Naphthalate copolymer (IA copolymer PENTT)
g = 115 ° C.).

The copolymer polyester was used as a raw material, melt-extruded from a die slit, cooled and solidified on a casting drum to form an unstretched film, and then successively formed in the same manner as in Example 1 under the film forming conditions shown in Table 1. The film was axially stretched to obtain a biaxially oriented film. Table 1 shows the results.

Example 9 Polymerization was carried out in the same manner as in Example 1 except that no lubricant was added, and the obtained polyethylene-2,6-naphthalenedicarboxylate having an intrinsic viscosity of 0.60 dl / g was used. To form a film. Table 1 shows the film forming conditions and results.

Comparative Example 1 A PEN containing silica particles having an intrinsic viscosity of 0.60 dl / g in Example 1 (Tg = 12
1 ° C.) instead of silica particles-containing polyethylene terephthalate (PET, Tg = 7) having an intrinsic viscosity of 0.60 dl / g.
(8 ° C.). Table 2 shows the film forming conditions and results. The transparency of the film was good, but the deformation resistance was poor.

[Comparative Example 2] The vertical direction (M
A film was formed in the same manner except that the stretching ratio in D) was 4.2 times, the stretching ratio in the transverse direction (TD) was 4.3 times, and the heat setting temperature was (Tg + 140) ° C. Table 2 shows the results. The haze value was high, the film was very cloudy, and the transparency was poor.

[Comparative Example 3] The vertical direction (M
A film was formed in the same manner except that the stretching ratio in D) was 3.0 times, the stretching ratio in the transverse direction (TD) was 3.1 times, and the heat setting temperature was (Tg + 140) ° C. Table 2 shows the results. The film was very cloudy and poor in transparency. Also, the deformation resistance was poor.

Comparative Example 4 Polymerization was carried out in the same manner as in Example 1 except that the amount of silica particles having an average particle diameter of 0.3 μm was changed to 0.4 part as a lubricant.
A film was formed using polyethylene-2,6-naphthalenedicarboxylate of 0 dl / g. Table 2 shows the film forming conditions and results. The film was very cloudy and poor in transparency. Also, the surface roughness was poor.

Comparative Example 5 A polymerization reaction was carried out in the same manner as in Example 5 except that 69 parts of dimethyl 2,6-naphthalenedicarboxylate, 31 parts of isophthalic acid and 60 parts of ethylene glycol were used, and the intrinsic viscosity was 0.59 dl / g. , Polyethylene-
2,6-Naphthalate copolymer (IA copolymer PENTT)
g = 108 ° C.).

Using this copolymer polyester as a raw material, it was melt-extruded from a die slit, cooled and solidified on a casting drum to form an unstretched film, and then successively formed in the same manner as in Example 1 under the film forming conditions shown in Table 1. The film was axially stretched to obtain a biaxially oriented film. Table 2 shows the results.

[0080]

[Table 1]

[0081]

[Table 2]

[0082]

According to the present invention, it is possible to provide a base film for an antiglare film having excellent transparency, glass scattering prevention effect and excellent deformation resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) B29L 7:00 11:00 F term (Reference) 4F071 AA45 AA45X AA88 AF14Y AF20Y AF30Y AH12 BA01 BB06 BB08 BC01 BC10 BC12 BC16 4F210 AA26C AA26E AB07 AB17 AE01 AG01 QC06 QG01 QG18 QW07 QW50 4J029 AA03 AB01 AB07 AC01 AC02 AD01 AD10 AE03 BA02 BA03 BA04 BA05 BA08 BA10 BD03A BF09 BF26 BH02 CA01 CA02 CA06 CB05 CC03A05

Claims (7)

[Claims] 1. A biaxially stretched film containing polyethylene-2,6-naphthalenedicarboxylate as a main component, wherein the film has a haze value of 5% or less and has a deformation resistance satisfying the following formula. Base film for anti-glare film. P / h ² ≧ 0.536 (h ≦ 0.1t) (where P is the load (gf) applied to the base film surface using an indenter, and h is the depth pushed by the indenter. (Μm), t represents the thickness (μm) of the base film) 2. The film according to claim 1, wherein the film comprises a copolymer or a mixture containing at least 80 mol% of polyethylene-2,6-naphthalenedicarboxylate.
The base film for an antiglare film according to 1. 3. The film has an intrinsic viscosity of 0.40 dl / g.
0.90 dl / g or less, and the sum of the Young's modulus in the machine direction (MD) and the transverse direction (TD) of the film is 900 kg.
/ Mm ² or more, and the difference between the Young's modulus in the machine direction (MD) and the transverse direction (TD) (| Young's modulus _MD -Young's modulus _TD |) is 100 kg.
/ Mm ² or less.
The base film for an antiglare film according to 1. 4. The film has a plane orientation coefficient (ns) of 0.2.
The base film for an anti-glare film according to any one of claims 1 to 3, wherein the base film has a surface roughness of not less than 50, a surface roughness of not more than 10 nm, and a thickness of not less than 50 µm and not more than 350 µm. 5. The base film for an antiglare film according to claim 1, wherein the stiffness of the film is 2.0 g or more. 6. An anti-glare film, characterized in that an adhesive layer is provided on one surface of the biaxially stretched film according to any one of claims 1 to 5, and the film is used by being attached to an image display device. . 7. The base film for an antiglare film according to claim 1, wherein the image display device is a cathode ray tube or a plasma display.