KR102020478B1 - Polarizing plate - Google Patents

Abstract

a와 b는 정수로서 1 이상이다.
MMA-BMA
여기서, MMA는 메틸 메트아크릴레이트(Methyl Methacrylate) 단위, BMA는 부틸 메트아크릴레이트(Butyl Methacrylate) 단위를 나타낸다.The present invention is an acrylic resin represented by the following formula (1) and polymethyl methacrylate {PMMA; Poly (methyl methacrylate)} is formed from a resin composition comprising particles of a material by a solvent casting method, an acrylic film characterized in that the coefficient of kinetic friction is 0.7 or less is provided on one side of the polarizer, triacetyl cellulose or acetyl group and buty The protective film containing a mixed fatty acid cellulose ester having a reel group relates to a polarizing plate provided on the other side of the polarizer, and the roll winding quality of the film is improved, and the quality can be maintained over time. The polarizing plate produced using also has excellent appearance quality.
[Formula 1]

a and b are 1 or more as integers.
MMA-BMA
Here, MMA represents a methyl methacrylate unit, and BMA represents a butyl methacrylate unit.

Description

Polarizing plate

The present invention provides an acrylic film having excellent winding quality on one side of the polarizer is secured slip properties and blocking properties during solvent casting, the protective film containing triacetyl cellulose or mixed fatty acid cellulose ester having an acetyl group and a butyryl group is The present invention relates to a polarizing plate provided on the other side of the polarizer and excellent in appearance quality.

Background Art In recent years, low power consumption, low voltage operation, and lightweight and thin liquid crystal display devices have been widely used in information display devices such as mobile phones, monitors for portable information terminal computers, and televisions. Such information display devices are required to be reliable under severe environments depending on the application. For example, a liquid crystal display device for a car navigation system may have a very high temperature and humidity in a vehicle in which it is placed, and the required temperature and humidity conditions are severe when compared to a normal television or personal computer monitor. And although a polarizing plate is used for a liquid crystal display device in order to enable the display, in the liquid crystal display device which requires such severe temperature and / or humidity conditions, it is calculated | required to have high durability also in the polarizing plate which comprises it.

The polarizing plate usually has a structure in which a transparent protective film is laminated on both surfaces or one side of a polarizing film made of a polyvinyl alcohol-based resin in which a dichroic dye is adsorbed and oriented. And conventionally, triacetyl cellulose (TAC) is widely used for this protective film, This protective film is adhere | attached with a polarizing film through the adhesive which consists of aqueous solution of polyvinyl alcohol-type resin. By the way, since the polarizing plate in which the protective film which consists of triacetyl cellulose was laminated | stacked has high water vapor transmission rate of triacetyl cellulose, when it uses for a long time in a high humidity heat environment, polarization performance may fall, or a protective film and a polarizing film may peel off. have. In order to solve such a problem, it was tried to use the (meth) acrylic-type resin film with low moisture permeability compared with a triacetyl cellulose film as a protective film of a polarizing plate.

Conventional acrylic protective films have been manufactured by melt casting, but have many advantages in terms of eco-friendliness such as thinning, mass production, and recycling of resins when manufactured by the solvent casting method. In the solvent casting method, the acrylic film is dissolved in a solvent and extruded by T-Die, and then the solvent is dried on the belt to make a film. The optimized particle is added to increase the impact strength and to secure the slip property for film transfer. Process is possible. In addition, the added particles should not be dissolved or deformed in the solvent.

Korean Patent No. 1250057 discloses a self-adhesive polarizing plate in which light leakage of an image display device does not occur easily even when the use environment is changed. The acrylic polymer constituting the pressure-sensitive adhesive layer has a predetermined amount of aromatic ring structure (meth The adhesive layer contains a transparent protective film when the acrylate monomer unit is contained and its content is determined according to the value of the photoelastic coefficient X of the transparent protective film, and the phase difference value of the transparent protective film changes due to environmental changes such as heating. It is proposed to adjust to generate a phase difference change of the opposite sign.

Korean Patent No. 1114354 discloses a protective film for an optical member having a pressure-sensitive adhesive layer containing a cured product of a photopolymerizable acrylic polymer, an antistatic agent and a polymerization initiator composition, wherein a crosslinking reaction is caused by radicals generated from an initiator by light irradiation. An appropriate amount of an antistatic agent is further blended into the composition comprising a photopolymerizable acrylic polymer and a polymerization initiator into which a photoactive group which can be introduced is added in a predetermined ratio, so that the aging step during curing can be omitted, while simplifying the manufacturing process, A protective film excellent in antistatic properties at peeling or use is disclosed.

Korean Patent Publication No. 2015-0061591 discloses a first functional layer (low moisture vapor barrier) formed by using a compound having a cyclic aliphatic hydrocarbon group and an ethylenically unsaturated double bond group, and a composition containing a urethane acrylate thereon. A technique for obtaining a polarizing plate protective film excellent in interlayer adhesion and uneven resistance to wind by using a specific amount of a fluoro aliphatic group-containing copolymer having a second functional layer formed and having a specific structure in the first functional layer has been proposed. .

Japanese Patent Application Laid-Open No. 2014-240905 discloses a protective film A having a film thickness and elastic modulus within a specific range and containing acrylic resin as a main component in order to manufacture a polarizing plate having excellent adhesion, rework, planarity, and visibility with a polarizer. The technical structure which laminated | stacked in order of retardation film B which has a polarizer and a cellulose derivative which has an ether bond and a substituent at least in a glucose skeleton in order, and has film A and film B bonded together through an ultraviolet curable adhesive is shown.

On the other hand, acrylic protective film has a problem of transportability such as breakage during film transfer due to its stacky property, and there is a problem that defect occurs due to sticking between films due to poor blocking property during long-term storage in a roll state, and thus maintaining film quality. It is necessary to secure sufficient slip and blocking properties.

Korean Registered Patent No. 1265007 Korean Patent No. 1114354 Korean Laid-Open Patent No. 2015-0061591 Japanese Laid-Open Patent No. 2014-240905

The present invention has been made to solve the above problems, an acrylic film produced by the Solvent casting method, excellent in slipperiness and blocking property is provided on one side of the polarizer, triacetyl cellulose or acetyl A protective film containing a mixed fatty acid cellulose ester having a group and a butyryl group is to provide a polarizing plate provided on the other side of the polarizer.

The present invention is an acrylic resin consisting of 70 to 98 parts by weight of methyl methacrylate units, 2 to 30 parts by weight of butyl methacrylate units, based on 100 parts by weight of the acrylic resin represented by Formula 1 below: Polymethylmethacrylate {PMMA; Poly (methyl methacrylate)} an acrylic film formed by the solvent casting method from an acrylic resin composition consisting of particles of a protective film containing triacetyl cellulose or mixed fatty acid cellulose ester having acetyl and butyryl groups on one side of the polarizer It is a polarizing plate with which the other side of this polarizer was equipped.

[Formula 1]

a and b are 1 or more as integers.

MMA-BMA

Here, MMA represents a methyl methacrylate unit, and BMA represents a butyl methacrylate unit.

Polymethylmethacrylate of the present invention {PMMA; Poly (methyl methacrylate)} particles have a diameter of 1 to 2.0 μm, and the content of the particles is 100 to 1000 ppm with respect to the main dope solution.

In this invention, it is preferable that the acrylic resin composition contains the acrylic film whose molecular weight is 50,000 g / mol-2,500,000 g / mol.

In the present invention, it is preferable to use a solvent of the solvent casting by mixing a halogenated hydrocarbon and an alcohol.

In the polarizing plate of the present invention, the kinetic coefficient of friction of the acrylic film is 0.7 or less, wherein the acrylic film is provided on one side of the polarizer, and contains triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group. It is a feature that a film is provided on the other side of the said polarizer.

According to the present invention, an acrylic film having high slip quality and excellent winding quality is provided on one side of the polarizer, and a protective film containing triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group is different from the polarizer. It is provided on one side to provide a polarizing plate excellent in appearance quality.

1 is a photograph showing the evaluation of the blocking of the protective film A of Example 1 of the present invention.
Figure 2 is a photograph showing the evaluation of the blocking of the protective film A of Comparative Example 1 of the present invention.
Figure 3 is a photograph showing the evaluation of the blocking of the protective film A of Comparative Example 2 of the present invention.
Figure 4 is a photograph showing the evaluation of the blocking of the protective film A of Comparative Example 3 of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, although the best form for implementing this invention is demonstrated in detail, this invention is not limited to these.

The inventors of the present invention have been studied to develop an acrylic film having excellent peeling force of the film when manufacturing a thin acrylic film by the solvent casting method, the average molecular weight of the resin composition in the range of 50,000 ~ 2,500,000g / mol, specific components By discovering that the acrylic protective film which was excellent in slipping property and blocking property by the resin composition containing this, and the winding quality was improved, it came to complete this invention.

Polarizing plate of the present invention is an acrylic resin represented by the following formula (1) and polymethyl methacrylate {PMMA; Poly (methyl methacrylate)} film thickness 20 to 60 μm containing protective film A having a thickness of 20 to 60 μm and triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group. The protective film B is a polarizing plate having a total film thickness of 60 to 180 μm formed by sandwiching both surfaces of the polarizer PVA, and has a copper friction coefficient of 0.7 or less.

[Formula 1]

a and b are 1 or more as integers.

MMA-BMA

Here, MMA represents a methyl methacrylate unit, and BMA represents a butyl methacrylate unit.

First, the acrylic resin of this invention is demonstrated. The acrylic resin of the present invention is a copolymer resin consisting of methyl methacrylate units and butyl methacrylate units, wherein each of the monomer units is included in the form of a repeating unit.

In consideration of optical properties, transparency, compatibility, processability and productivity, 70 to 98 parts by weight of methyl methacrylate units, and 2 to 30 butyl methacrylate units, based on 100 parts by weight of acrylic resin It is preferably made of parts by weight. This is because when the content of the methyl methacrylate unit is in the above range, excellent retardation characteristics and optical characteristics can be obtained. If the methyl methacrylate unit content is less than 70 parts by weight, the optical performance of the protective film worsens, and if it exceeds 98 parts by weight, the thickness uniformity of the protective film is lowered.

In addition, with respect to 100 parts by weight of the acrylic resin, the content of the butyl methacrylate unit is preferably made of 2 to 30 parts by weight. This is because desirable optical properties can be obtained when the content of butyl methacrylate units is in the above range.

In the present invention, slip and blocking properties are secured by further adding PMMA particles in addition to silica particles (R812 by EVOKIN) as the slip material. At this time, the diameter of the PMMA particles is preferably 1 ~ 2.0㎛. When the particle diameter is less than 1 μm, the effect of the desired invention does not appear sufficiently, and when the diameter is more than 2 μm, the quality of the protective film is poor. The content of the particles is preferably 100 ~ 1000ppm with respect to the solid content of the main dope liquid. When the content of the particles of the PMMA material of the present invention is 100ppm or less, there is a lack of blocking properties between the film and the stacked acrylic films are pressed together, if the content is 1000ppm or more there is a fear that the surface is too rough.

In this invention, the impact strength of a film improves by adding nanoparticles which do not melt | dissolve in a solvent and do not produce deformation to the said acrylic resin, and film forming and film conveyance become easy. As the impact strength improving agent of the present invention, it is preferable to use core-shell rubber particles (CSR) or silica particles. It is preferable that the diameter of CSR is 100-300 nm. When the diameter of CSR is less than 100 nm, the effect of the objective invention does not appear sufficiently, and when it exceeds 300 nm, the quality of a protective film will become bad.

The content of the silica particles is preferably 0.005 parts by weight to 0.1 parts by weight with respect to 100 parts by weight of the main dope liquid, and the content of the core-shell rubber particles (CSR) is 2 parts by weight or more and less than 10 parts by weight with respect to 100 parts by weight of the main dope liquid. This is preferred. When the content of the nanoparticles of the present invention is in the above range, it is possible to provide a protective film excellent in both hardness and flexibility.

The core shell rubber (Core Shell Rubber) is made of one or two or more selected from the group consisting of styrene butadiene rubber (Styrene Butadiene Rubber), polybutadiene (Polybutadiene, PBD), acrylic ester (Acrylic Ester), It is preferable to include a graft copolymer having one or two or more core-shell structures selected from the group consisting of methyl methacryl (MMA), styrene (Styrene) and acrylic ester (Acrylic Ester).

It is preferable that the resin composition of this invention is 50,000-2,500,000 g / mol. In this case, if the molecular weight is less than 50,000g / mol, the production efficiency of the film is lowered, and if it exceeds 2,500,000 is because molding is not easy. Moreover, it is preferable that the glass transition temperature (Tg) of the resin composition of this invention is 120 degreeC or more. Even if the glass transition temperature is less than the above range, the handleability is poor, which is not preferable.

It is preferable that the acrylic film of this invention is 20 or more and 60 micrometers or less in film thickness. If the thickness of the protective film is less than 20㎛ does not express sufficient retardation characteristics, if the thickness of the protective film exceeds 60㎛ is not suitable for use in thin polarizing plate.

It is preferable that the acrylic film of this invention is 10 nm or less on condition of 23 degreeC and 55% RH of in-plane retardation Ro and thickness direction retardation Rth defined by following formula (1).

[Equation 1]

Ro = (nx-ny) * d

Rth = {(nx + ny) / 2-nz} * d

In Equation 1, d is the thickness (nm) of the film, nx is the horizontal maximum refractive index in the plane of the film, ny is the vertical maximum refractive index in the film plane, nz is the maximum thickness refractive index of the film.

When in-plane and thickness direction retardation exceeds 10 nm, the performance as an isotropic optical film falls.

It is preferable that the acrylic film of this invention has a coefficient of dynamic friction 0.7 or less. If the coefficient of dynamic friction is greater than 0.7, the slipperiness of the film is poor.

Hereinafter, the preferable manufacturing method of this invention is demonstrated in detail.

Preparation of Acrylic Polymer Resin

In order to manufacture the protective film of this invention, the copolymer resin solution of a methyl methacrylate monomer and a butyl methacrylate monomer is prepared first. There is no particular limitation on the copolymer production method of these monomers, and it can be prepared according to a copolymer resin production method well known in the art such as suspension polymerization, emulsion polymerization, bulk polymerization or solution polymerization.

Preparation of Dilute Solution Containing Acrylic Resin and Nano Particles

In this invention, a film is manufactured by the solvent casting method (solution film formation method). The solvent casting method is a method of casting a solution (dope) obtained by dissolving an acrylic copolymer in a casting solvent on a support, and evaporating the solvent to form a film. Preparation of dope is by the method of mixing the acrylic copolymer resin solution and coadditive prepared above with the casting solvent.

When the film is produced by the solvent casting method, the solvent for producing the acrylic resin composition (dope) is preferably an organic solvent. As the organic solvent, halogenated hydrocarbons are preferably used, and halogenated hydrocarbons include chlorinated hydrocarbons, methylene chloride and chloroform, and methylene chloride is most preferably used.

Moreover, you may mix and use organic solvents other than halogenated hydrocarbon as needed. Organic solvents other than halogenated hydrocarbons include esters, ketones, ethers, alcohols and hydrocarbons. As ester, methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acylate, ethyl acylate, pentyl acylate, etc. can be used. As ketone, acetone, methyl ethyl ketone, diethyl ketone, di Isobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc. can be used, and ether is diisopropyl ether, dimethoxymethane, dimethoxyethane, 1, 4- dioxane, 1, 3- dioxane Solan, tetrahydrofuran, anisole, phentol, etc. can be used, and alcohol, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2 -Pentanol, 2-methyl-2-butanol, cyclohexanol, 2-fluoroethanol, 2,2,2, -trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol Use

More preferably, methylene chloride may be used as the main solvent and alcohol may be used as the subsolvent. Specifically, the mixed solvent of methylene chloride and alcohol is preferably mixed in a weight ratio within the range of 80:20 to 95: 5. More preferred are solvents mixed in an 85:15 weight ratio of methylene chloride and methanol.

Supplementary additives may be further used in the production of the acrylic protective film. To the acrylic copolymer solution (dope), various auxiliary additives depending on the use in each manufacturing process, for example, an ultraviolet additive, fine particles, an infrared absorber, and an auxiliary additive such as a release agent can be added. Specific kinds of such additives may be used without limitation as long as it is conventionally used in the art, the content is preferably used in a range that does not lower the physical properties of the film. The timing of adding the additive is determined by the type of the additive. The process of adding an additive at the end of dope preparation can also be performed.

As the additive of the present invention, particles of PMMA material were used.

The acrylic resin composition obtained as mentioned above can be manufactured by normal temperature, high temperature, or low temperature dissolution method.

Production Process

In the solvent cast method of the present invention, the acrylic resin composition solution is cast on the metal support from the nozzle of the press die and left for a predetermined time to form a film in a semi-dry state. Then, the said semi-dry state film is peeled from a metal support body, it transfers to a drying system, and it removes the said solvent by drying. And a uniaxial stretching process or a biaxial stretching process is performed with respect to the dry film. This drawing process

It is possible to improve the film uniformity and retardation value of a protective film by implementation of.

Specifically, the acrylic resin composition solution obtained as described above is cast on a support through a casting die to form an acrylic sheet. Here, the support transfers the casting stock solution on the sheet extruded from the die, and evaporates the solvent present in the casting stock solution to form a film into an acrylic film. It is preferable that the support or the surface thereof is made of a metal, and the surface is mirror-finished, and a metal belt such as a stainless steel belt is preferably used as the support. The surface temperature of the metal support is advantageous because the higher the temperature, the faster the evaporation of the solvent present in the casting stock solution. However, if the temperature is too high, the casting stock solution may foam or the planarity may deteriorate. Although it can vary, 0-75 degreeC is preferable and 5-45 degreeC is more preferable. The support may be a metal support in the form of a planar conveyor belt.

The acrylic sheet thus formed is subjected to a drawing step in the tender, and the preheating process has a glass transition temperature (Tg) of acrylic flake (110 g) or more. After the acrylic film of the present invention is subjected to the stretching step in the tender under the above conditions, the film may be completed through the drying step in the dryer after removing the left and right ends of the film damaged by the clip or pin of the tender.

When using a tender stretching apparatus, it is preferable to use the apparatus which can control the grip length of a film from left to right by the right and left holding means of a tender. The stretching operation may be performed by dividing into multiple stages, and it is also preferable to perform biaxial stretching in the casting direction and the width direction. In addition, when performing biaxial stretching, simultaneous biaxial stretching may be performed and you may carry out in steps. In this case, with stage, it is also possible to perform extending | stretching different from a extending direction sequentially, it is also possible to divide extending | stretching of the same direction into multiple steps, and to add extending | stretching of another direction to any one of them. In addition, simultaneous biaxial stretching also includes the case where the stretching is performed in one direction and the other is relaxed by shrinking the tension. The preferable draw ratio of simultaneous biaxial stretching can be taken in the range of 1.01 time-2.0 time in both the width direction and the longitudinal direction.

The drying means generally blows hot air on both sides of the web, but there is also a means of heating the micro web instead of the wind. Too rapid drying tends to impair the planarity of the finished film.

The acrylic film of the present invention prepared according to the above method is characterized in that the coefficient of friction of 0.7 or less, the present invention is provided with the acrylic film on one side of the polarizer, the other side of the polarizer triacetyl cellulose or A polarizing plate provided with a protective film containing a mixed fatty acid cellulose ester having an acetyl group and a butyryl group.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not limited by the following examples.

Example  One

<Step 1> Acrylic Polymer Resin

Acrylic represented by the following formula (1) was used.

At this time, the MMA unit is 95 parts by weight, and the BMA unit is 5 parts by weight.

[Formula 1]

a and b are 1 or more as integers.

Step 2 Preparation of Dilute Acrylic Polymer Solution Containing Nanoparticles

16.47 parts by weight of the acrylic polymer solution, 3.69 parts by weight of CSR as nanoparticles, 0.01 parts by weight of silica, 65.18 parts by weight of methylene chloride and 14.31 parts by weight of a mixed solvent were mixed to prepare a dilute acrylic polymer solution containing nanoparticles. . In addition to silica (R812 by EVOKIN, Inc.) as a slip material, 0.01 wt% of PMMA particles were added to the total dope solution. The particles of PMMA material is SOKEN Corporation MX150, the size of the particles is 1 ~ 2㎛.

<Step 3> Preparation of the protective film A

The dope solution was sufficiently mixed with an in-line mixer. The composition of the dope is 65.18 parts by weight of methylene chloride, 14.31 parts by weight of methanol, 16.47 parts by weight of acrylic polymer, 3.69 parts by weight of CSR, 0.33 parts by weight of Tinvuin 928 (manufactured by BASF), an ultraviolet absorber, 0.01 parts by weight of Silica and PMMA 0.01 part by weight of particles.

Thereafter, the dope was uniformly cast on a stainless band support having a width of 2000 mm using a belt casting apparatus. The solvent was evaporated off the stainless band support and peeled off from the stainless band support. Subsequently, both ends of the web were gripped with a tender and stretched so that the stretching ratio in the TD direction was 1.5 times in a 130 ° C temperature environment. After extending | stretching, it hold | maintains for several seconds in the state which kept the width, relaxed the tension in the width direction, relaxed in the width direction, conveyed for 35 minutes in the drying section set to 90 degreeC, and performed drying, width 1900mm, and an edge part An acrylic film having a thickness of 40 µm having a width of 10 mm and a knurling having a height of 8 µm was prepared.

<Step 4> Preparation of the protective film B

The dope was made under the same conditions as in Example 1, but triacetyl cellulose (TAC) was used, and stretching was performed at 130 ° C. under a temperature of 180 ° C.

<Step 5> Preparation of the polarizing plate

PVA was laminated using the protective films A and B to form a polarizing plate.

Comparative example  One

The dope was prepared under the same conditions as in Example 1, but the content of BMA in the acrylic resin was 0% by weight, only R812 manufactured by EVOKIN, silica particles, was added as a slip material, and particles of PMMA material were excluded.

Comparative example  2

The dope was made under the same conditions as in Example 1, but only R812 manufactured by EVOKIN, which is a silica particle, was added as a slip material, and particles of PMMA material were excluded.

Comparative example  3

The dope is made under the same conditions as in Example 1, but the content of BMA in the acrylic resin is 0% by weight.

One. Haze  Measure

Haze was measured for the films of Examples and Comparative Examples 1 to 3 and the results are shown in Table 1.

2. Kinetic friction coefficient  Measure

The coefficient of kinetic friction was measured for the films of Examples and Comparative Examples 1 to 3 thus obtained, and the results are shown in Table 1.

3. Blocking evaluation

For the films of Examples and Comparative Examples 1 to 3 thus obtained, blocking was evaluated in the following manner and the results are shown in Table 1 and FIGS. 1 to 4.

end. Evaluation method and condition

-Put the Acryl Air Side / Belt Side Stacker (Heat Gradient Tester) on the sample holder and press the Bar (approx. 20X1cm) at a constant pressure (6kg / ㎠) to determine the degree of pressing of the film. )

-Measurement environment: temperature 24 ± 2 ℃, humidity 30 ± 2%

I. Measuring instrument

-Heat Gradient Tester (One bar type, Pressure 6kg / ㎠)

4. Polarizer appearance quality evaluation

The appearance of the polarizing plates of Examples and Comparative Examples 1 to 3 was visually evaluated.

division unit Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 1 Acryl resin - MMA MMA + BMA MMA MMA + BMA Slip material
Type / content ppm EVONIK R812
500 ppm EVONIK R812
500 ppm EVONIK R812
500 ppm
+
SOKEN Corporation MX150
500 ppm EVONIK R812
500 ppm
+
SOKEN Corporation MX150
500 ppm Surface properties Haze % 0.36 0.33 0.31 0.30 Dynamic friction coefficient
(Air / Belt) - 1.12 / 0.94 1.10 / 0.67 1.00 / 0.88 0.48 / 0.55 Roll winding quality Blocking rating
(6kg / ㎠ * 10min)
24 ℃ / 30% Air
/ Belt Press Press Press Good without sticking Polarizer properties Protective film B - Triacetyl cellulose (film thickness 60㎛) Appearance quality - Scratch, Stamped, Pressed Scratch, Stamped, Pressed Scratch, Stamped, Pressed Good

As shown in Table 1, when the acrylic resin and PMMA particles according to the present invention are used to make a film by solvent casting, haze, dynamic friction coefficient, and blocking evaluation can be confirmed to be excellent.

Among the slip materials, EVONIK R812, which is made of silica and has a small particle size, is responsible for slipping, while SOKEN MX150, which is PMMA and has a large particle size, is responsible for blocking. Acrylic films are very stacky, but some of the BMAs with long molecular chains are included to reduce the stacky properties.

Therefore, as these components are bonded together, the acrylic film according to the present invention is excellent in slipping and blocking properties, the winding quality is good, and the quality can be maintained over time.

It can be seen that the polarizing plate of the present invention produced using the acrylic film according to the present invention is also good in appearance quality.

Claims (5)

To 100 parts by weight of the acrylic resin represented by the formula (1), 70 to 98 parts by weight of methyl methacrylate (Methyl Methacrylate) unit, 2 to 30 parts by weight of butyl methacrylate (Butyl Methacrylate) unit and acrylic resin and polymethylmeth Acrylate {PMMA; Poly (methyl methacrylate)} an acrylic film formed by the solvent casting method from an acrylic resin composition consisting of particles is provided on one side of the polarizer,
The diameter of the particles of the polymethyl methacrylate material is 1 ~ 2.0 ㎛, the content of the particles of the polymethylmethacrylate material with respect to the main dope liquid is 100 ~ 1000ppm,
A polarizing plate provided with a protective film containing triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group on the other side of the polarizer.
[Formula 1]

a and b are 1 or more as integers.
MMA-BMA
Here, MMA represents a methyl methacrylate unit, and BMA represents a butyl methacrylate unit.
delete The method of claim 1,
An acrylic film having a molecular weight of 50,000 g / mol to 2,500,000 g / mol of the acrylic resin composition, which is provided on one side of the polarizer, and contains triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group. The polarizing plate with which a film was provided in the other side of the said polarizer.
The method of claim 1,
An acrylic film comprising a solvent of the solvent casting by mixing a halogenated hydrocarbon and an alcohol is provided on one side of the polarizer, the protective film containing triacetyl cellulose or mixed fatty acid cellulose ester having an acetyl group and a butyryl group The polarizing plate provided in the other side of the said polarizer.
The method of claim 1,
An acrylic film having a dynamic friction coefficient of the acrylic film of 0.7 or less is provided on one side of the polarizer, and a protective film containing triacetyl cellulose or a mixed fatty acid cellulose ester having an acetyl group and a butyryl group is the other side of the polarizer. Polarizing plate provided on the surface.

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