KR102088823B1 - 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 formula (1) and polymethyl methacrylate {PMMA; Poly (methyl methacrylate)} is formed by a solvent casting method from a resin composition containing particles of a material, and an acrylic film characterized by having a dynamic friction coefficient of 0.7 or less is provided on one side of the polarizer, and contains a cyclic olefin resin. The protective film is a polarizing plate provided on the other side of the polarizer, the roll roll quality of the film is improved, and quality can be maintained over time. great.
[Formula 1]

a and b are 1 or more as an integer.
MMA-BMA
Here, MMA is a methyl methacrylate unit, and BMA is a butyl methacrylate unit.

Description

Polarizing plate

According to the present invention, an acrylic film having excellent winding quality is provided on one side of the polarizer, and a protective film containing a cyclic olefin resin is provided on the other side of the polarizer when the solvent is cast and the blocking property is secured. It relates to a polarizing plate having excellent quality.

In recent years, small power consumption, low voltage operation, and a lightweight and thin liquid crystal display device are widely used in information display devices such as mobile phones, portable information terminal computer monitors, and televisions. Reliability of such information display devices in harsh environments is required 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 car in which it is placed, and the required temperature and humidity conditions are stricter than that of a conventional television or personal computer monitor. In addition, a polarizing plate is used in the liquid crystal display device to enable the display. In the liquid crystal display device in which such strict temperature and / or humidity conditions are required, it is required that the polarizing plate constituting it has high durability.

The polarizing plate usually has a structure in which a transparent protective film is laminated on both sides 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, and the protective film is adhered to the polarizing film through an adhesive made of an aqueous solution of a polyvinyl alcohol-based resin. By the way, the polarizing plate on which the protective film made of triacetyl cellulose is laminated has high moisture permeability of triacetyl cellulose, and therefore, when used for a long time in a high-humidity heat environment, the polarization performance may deteriorate or the protective film and the polarizing film may peel off. have. In order to solve this problem, it has been attempted to use a (meth) acrylic resin film having a low moisture permeability as compared to a triacetyl cellulose film as a protective film for a polarizing plate.

Existing acrylic-based protective films have been manufactured by a melt casting method, but have many advantages in terms of eco-friendliness such as thinning, mass production, and recycling of resins when manufacturing by the solvent casting method. Solvent casting method is to dissolve the acrylic film in a solvent and extrude it with T-Die, then dry the solvent in the belt to make a film. It is necessary to increase the impact strength by adding optimized particles and secure slip properties for film transfer. The process is possible. Also, the particles added at this time should not be dissolved or deformed in the solvent.

Korean Registered Patent No. 12,5007 discloses an adhesive polarizing plate in which light leakage of an image display device does not easily occur even due to a change in the use environment, wherein the acrylic polymer constituting the adhesive layer has a predetermined amount of (meth) ) Containing an acrylate monomer unit, its content is determined according to the value of the photoelastic coefficient X of the transparent protective film, and when the phase difference value of the transparent protective film is changed by environmental changes such as heating, the pressure-sensitive adhesive layer is a transparent protective film It has been proposed to adjust to generate a phase difference change of the opposite sign.

Korean Registered Patent No. 1114354 is a protective film for an optical member having an adhesive layer containing a cured product of a photopolymerizable acrylic polymer, an antistatic agent and a polymerization initiator composition, and causes crosslinking reaction by radicals generated in the initiator by light irradiation. A composition containing a photopolymerizable acrylic polymer and a polymerization initiator in which a photoactive group can be introduced is added to the composition in a predetermined ratio, and an appropriate amount of an antistatic agent can be added, so that the aging process during curing can be omitted, simplifying the manufacturing process, A protective film having excellent antistatic properties when peeling or using is disclosed.

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

Japanese Unexamined Patent Publication No. 2014-240905 has a film thickness and an elastic modulus within a specific range, and a protective film A composed mainly of an acrylic resin in order to produce a polarizing plate excellent in adhesiveness, reworkability, planarity and visibility with a polarizer, The polarizer, the glucose skeleton is laminated at least in the order of the retardation film B mainly composed of a cellulose derivative having an ether bond and a substituent, and a technical configuration is proposed in which both the film A and the film B are bonded through an ultraviolet curable adhesive.

On the other hand, the acrylic protective film has a problem in transportability such as rupture when transporting the film due to the stacky properties, and there is a problem in that the blocking property is poor when it is stored for a long time in a roll state and sticks to each other, causing defects, thereby maintaining the film quality. For this, it is necessary to secure sufficient slip and blocking properties.

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

The present invention has been devised to solve the above problems, and an acrylic film produced by a solvent casting method, having excellent slip and blocking properties, has improved winding quality, and is provided on one side of the polarizer, and a cyclic olefin resin. It is intended to provide a polarizing plate having a protective film on the other side of the polarizer.

The present invention is represented by the following formula (1), with respect to 100 parts by weight of acrylic resin, methyl methacrylate (Methyl Methacrylate) units 70 to 98 parts by weight, butyl methacrylate (Butyl Methacrylate) units 2 to 30 parts by weight of acrylic resin And polymethyl methacrylate {PMMA; An acrylic film formed by a solvent casting method from an acrylic resin composition containing particles of poly (methyl methacrylate), core-shell rubber particles (CSR), and silica particles is provided on one side of the polarizer, and the cyclic olefin resin The protective film contained is a polarizing plate provided on the other side of the polarizer.

[Formula 1]

a and b are 1 or more as an integer.

MMA-BMA

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

Polymethyl methacrylate of this invention {PMMA; The particles of the poly (methyl methacrylate)} material have a diameter of 1 to 2.0 μm, and the content of the particles is preferably 100 to 1000 ppm for the acrylic resin composition.

In the present invention, it is preferable that the acrylic resin composition includes an acrylic film having a molecular weight of 50,000 g / mol to 2,500,000 g / mol.

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

In the polarizing plate of the present invention, an acrylic film characterized in that a dynamic friction coefficient of the acrylic film is 0.7 or less is provided on one side of the polarizer, and a protective film containing a cyclic olefin resin is provided on the other side of the polarizer. It is equipped with features.

In the present invention, the slip and blocking properties are secured, so that an acrylic film excellent in winding quality is provided on one side of the polarizer, and a protective film containing a cyclic olefin resin is provided on the other side of the polarizer, so that the appearance quality is excellent. Provided is a polarizing plate.

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

Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited to these.

The present inventors have repeatedly researched to develop an acrylic film having excellent peel strength when film is manufactured by using a solvent casting method to form a thin film of an acrylic film, and the average molecular weight of the resin composition is in the range of 50,000 to 2,500,000 g / mol. It has been discovered that an acrylic protective film having improved slipperiness and improved winding quality is obtained by a resin composition comprising a, and the present invention has been completed.

The polarizing plate of the present invention is an acrylic resin represented by the following formula (1) and polymethyl methacrylate {PMMA; Poly (methyl methacrylate)} protective film A formed from a resin composition containing particles of material 20 to 60 μm and protective film B having a film thickness of 20 to 100 μm containing cyclic olefin resin B are polarizers (PVA) A polarizing plate having a total thickness of 60 to 180 μm sandwiched by both surfaces of the polarizing plate, wherein the protective film A has a dynamic friction coefficient of 0.7 or less.

[Formula 1]

a and b are 1 or more as an integer.

MMA-BMA

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

First, the acrylic resin of the present invention will be described. The acrylic resin of the present invention is a copolymer resin composed of methyl methacrylate units and butyl methacrylate units, and the monomer units are included in the form of repeat units.

In consideration of optical properties, transparency, compatibility, processability and productivity, with respect to 100 parts by weight of acrylic resin, methyl methacrylate (Methyl Methacrylate) units 70 to 98 parts by weight, butyl methacrylate (Butyl Methacrylate) units 2 to 30 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. When the methyl methacrylate unit content is less than 70 parts by weight, the optical performance of the protective film deteriorates, and when it exceeds 98 parts by weight, the thickness uniformity of the protective film decreases.

Further, 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 the butyl methacrylate unit is in the above range.

In the present invention, slip and blocking properties are secured by adding PMMA material particles in addition to the silica particles (R812 from EVOKIN) as slip materials. At this time, the diameter of the PMMA particles is preferably 1 ~ 2.0㎛. When the diameter of the particles is less than 1 μm, the effect of the desired invention does not sufficiently appear, and when it exceeds 2 μm, the quality of the protective film becomes poor. The content of the particles is preferably 100 to 1000 ppm with respect to the solid content of the acrylic resin composition. If the content of the particles of the PMMA material of the present invention is 100 ppm or less, the blocking properties between the films are insufficient, and the stacked acrylic films are pressed against each other, and if it is 1000 ppm or more, the surface is too rough, which may cause scratching.

In the present invention, the impact strength of the film is improved by adding nanoparticles that are not soluble in the solvent and are not deformed to the acrylic resin, thereby facilitating film forming and film transfer. As the impact strength improver of the present invention, it is preferable to use core-shell rubber particles (CSR; Core Shell Rubber) or silica particles. The diameter of the CSR is preferably 100 to 300nm. When the diameter of the CSR is less than 100 nm, the effect of the desired invention does not sufficiently appear, and when it exceeds 300 nm, the quality of the protective film becomes poor.

The content of the silica particles is preferably 0.005 parts by weight to 0.1 parts by weight based on 100 parts by weight of the acrylic resin composition, and the content of core-shell rubber particles (CSR) is 2 parts by weight or more and less than 10 parts by weight based on 100 parts by weight of the acrylic resin composition 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 cores selected from the group consisting of styrene butadiene rubber, polybutadiene (PBD), and acrylic ester, It is preferable to include a graft copolymer as having one or two or more core-shell structures selected from the group consisting of methyl methacryl (MMA), styrene, and acrylic ester.

The resin composition of the present invention preferably has a molecular weight of 50,000-2,500,000 g / mol. At this time, if the molecular weight is less than 50,000 g / mol, the production efficiency of the film decreases, and if it exceeds 2,500,000, molding processing is not easy. In addition, the glass transition temperature (Tg) of the resin composition of the present invention is preferably 120 ° C or higher. Even if the glass transition temperature is less than the above range, the handleability is poor and it is not preferable.

The acrylic film of the present invention preferably has a film thickness of 20 or more and 60 µm or less. When the thickness of the protective film is less than 20 μm, sufficient retardation characteristics are not exhibited, and when the thickness of the protective film exceeds 60 μm, it is unsuitable for use in a thin polarizing plate.

It is preferable that the acrylic film of the present invention has an in-plane retardation Ro and a thickness direction retardation Rth defined by the following Equation 1 below 10 nm under conditions of 23 ° C and 55% RH.

[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 maximum refractive index in the horizontal direction in the plane of the film, ny is the maximum refractive index in the vertical direction in the film plane, and nz is the maximum refractive index in the thickness direction of the film.

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

The acrylic film of the present invention preferably has a coefficient of dynamic friction of 0.7 or less. When the coefficient of friction is more than 0.7, the slip property of the film is poor.

Hereinafter, a preferred manufacturing method of the present invention will be described in detail.

Preparation of acrylic resin

To prepare the protective film of the present invention, first, a copolymer resin solution of methyl methacrylate monomer and butyl methacrylate monomer is prepared. There is no particular limitation on the method for producing a copolymer of these monomers, and it may be prepared according to a method for preparing a copolymer resin well known in the art, such as suspension polymerization, emulsion polymerization, bulk polymerization, or solution polymerization.

Preparation of acrylic resin composition comprising acrylic resin and nanoparticles

In the present invention, a film is produced by a solvent casting method (solution film forming method). The solvent casting method is a method of casting a solution (acrylic resin composition) obtained by dissolving an acrylic copolymer in a casting solvent on a support, and evaporating the solvent to form a film. Preparation of the acrylic resin composition is by a method of mixing the above-mentioned acrylic copolymer resin solution and a co-additive in a casting solvent.

When a film is produced by a solvent casting method, an organic solvent is preferably used as a solvent for preparing the acrylic resin composition. It is preferable to use halogenated hydrocarbons as the organic solvent, and chlorinated hydrocarbons, methylene chloride and chloroform are used as the halogenated hydrocarbons, and methylene chloride is most preferred.

Further, if necessary, an organic solvent other than halogenated hydrocarbons may be mixed and used. Organic solvents other than halogenated hydrocarbons include esters, ketones, ethers, alcohols and hydrocarbons. As the ester, methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acylate, ethyl acylate, pentyl acylate, etc. can be used, and acetone, methyl ethyl ketone, diethyl ketone, di as ketone Isobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc. can be used, and diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxane can be used as ether. Solan, tetrahydrofuran, anisole, phenitol, etc. can be used, and alcohols include 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, -triflooroethanol, 2,2,3,3-tetrafluoro-1-propanol, etc. Use

More preferably, methylene chloride may be used as the main solvent, and alcohol may be used as the sub-solvent. Specifically, the mixing ratio of methylene chloride and alcohol is preferably a mixed solvent mixed in a weight ratio within the range of 80:20 to 95: 5. Methylene chloride and methanol are more preferably mixed in a ratio of 85:15 by weight.

In the production of the acrylic protective film, auxiliary additives may be further used. To the acrylic resin composition, various auxiliary additives according to the use in each manufacturing process, for example, ultraviolet additives, particulates, infrared absorbers, and auxiliary additives such as a release agent may be added. Specific types of these additives can be used without limitation as long as they are commonly used in the field, and the content is preferably used in a range that does not degrade the physical properties of the film. The timing of adding the additive depends on the type of additive. A process of adding an additive at the end of preparing the acrylic resin composition can also be carried out.

PMMA material particles were used as the additive of the present invention.

The acrylic resin composition obtained as described above may be prepared according to a normal temperature, high temperature or low temperature melting method.

Production process

In the solvent casting method of the present invention, the acrylic resin composition solution is flexible on a metal support from a nozzle of a press die and left for a predetermined time to form a semi-dried film. Thereafter, the film in the semi-dried state is peeled from the metal support, transferred to a drying system, and dried to remove the solvent. Then, a uniaxial stretching step or a biaxial stretching step is performed on the dried film. This drawing process

It is possible to improve the film uniformity and retardation value of the protective film by the 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 serves to evaporate the solvent present in the casting stock solution while transferring the casting stock solution on the sheet extruded from the die to form a film with an acrylic film. The support or its surface is made of metal, and the surface is preferably 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, but if it is too high, the casting stock solution foams or the flatness suffers, and depending on the solvent used, Although it may vary, 0 to 75 ° C is preferable, and 5 to 45 ° C is more preferable. As the support, a metal support in the form of a flat conveyor belt may be used.

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

When using a tender stretching apparatus, it is preferable to use the apparatus which can control the gripping length of a film from left and right by means of the left and right holding means of a tender. The stretching operation may be performed in multiple stages, or biaxial stretching in the flexible direction and the width direction is also preferable. In addition, when biaxial stretching is performed, simultaneous biaxial stretching may be performed or may be carried out stepwise. In this case, stepwise, it is also possible to sequentially perform stretching in different stretching directions, dividing stretching in the same direction into multiple stages, and adding stretching in the other direction to any one of them. In addition, simultaneous biaxial stretching also includes stretching in one direction and contracting the other by reducing tension. The preferred stretching ratio of simultaneous biaxial stretching can be taken in a range of 1.01 to 2.0 times in both the width direction and the length direction.

As the drying means, it is common to blow 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 flatness of the finished film.

The acrylic film of the present invention manufactured according to the above method is characterized in that the friction coefficient is 0.7 or less, and the present invention is provided with the acrylic film on one side of the polarizer, and the other side of the polarizer is cyclic olefin-based. It provides a polarizing plate having a protective film containing a resin.

Hereinafter, the present invention will be described in more detail based on examples. However, the present invention is not limited by the following examples.

Example  One

<Step 1> Acrylic polymer resin

Acrylic shown in Chemical 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 an integer.

<Step 2> Preparation of dilute acrylic resin composition solution containing nanoparticles

16.47 parts by weight of the acrylic polymer solution, 3.69 parts by weight of CSR, 0.01 parts by weight of silica, and 65.18 parts by weight of methylene chloride and 14.31 parts by weight of methanol were mixed to prepare a dilute acrylic polymer solution containing nanoparticles. . Here, as a slip material, in addition to silica (EVOKIN R812), particles of PMMA material were added in an amount of 0.01% by weight relative to the total acrylic resin composition. The particles of the PMMA material are SOKEN MX150, and the size of the particles is 1 to 2 μm.

<Step 3> Preparation of protective film A

The acrylic resin composition solution was thoroughly mixed with an in-line mixer. At this time, the composition of the acrylic resin composition solution 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), 0.01 parts by weight of Silica, and It is 0.01 parts by weight of particles of PMMA material.

Thereafter, the solution was uniformly flexible to a stainless band support having a width of 2000 mm using a belt casting device. The solvent was evaporated on the stainless band support and peeled from the stainless band support. Subsequently, both ends of the web were gripped with a tender, and stretched so that the draw ratio in the TD direction was 1.5 times in a 130 ° C temperature environment. After stretching, the width is maintained for a few seconds, the tension in the width direction is relaxed, the width direction is relaxed, and then conveyed for 35 minutes in a drying section set at 90 ° C. to dry for drying to produce a width of 1900 mm and further ends An acrylic film having a thickness of 10 mm and a thickness of 8 μm and a thickness of 40 μm was prepared.

<Step 4> Preparation of protective film B

The dope was made under the same conditions as in Example 1, and a cyclic olefin resin was used, and the stretching was performed at 130% under a temperature of 180 ° C. The composition of the dope was composed of 23% by weight of COP resin, 4.07% by weight of Plasticizer, and 0.04% by weight of silica based on 100% by weight of the main dope solution.

<Step 5> Preparation of polarizing plate

A polarizing plate was made by laminating PVA using the protective films A and B.

Comparative example  One

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

Comparative example  2

An acrylic resin composition was prepared under the same conditions as in Example 1, but only R812 of EVOKIN, a silica particle, was added as a slip material, and particles of PMMA were excluded.

Comparative example  3

An acrylic resin composition was prepared under the same conditions as in Example 1, but the content of BMA in the acrylic resin was 0% by weight.

One. Haze  Measure

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

2. Dynamic friction coefficient  Measure

The dynamic friction coefficients of the films of Example 1 and Comparative Examples 1 to 3 thus obtained were measured, and the results are shown in Table 1.

3. Blocking evaluation

For the films of Example 1 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 methods and conditions

-Acryl Air / Belt-side lamination (10ea) meter (Heat Gradient Tester) Place on the sample base and press the bar (about 20X1cm) at a constant pressure (6kg / ㎠) to determine the degree of film pressing (press for 10 minutes at room temperature) )

-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 appearances of the polarizing plates of Examples and Comparative Examples 1 to 3 were 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 company R812
500ppm EVONIK company R812
500ppm EVONIK company R812
500ppm
+
SOKEN Company MX150
500ppm EVONIK company R812
500ppm
+
SOKEN Company MX150
500ppm 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 evaluation
(6kg / ㎠ * 10min)
24 ℃ / 30% Air
/ Belt Press Press Press Good without sticking Polarizer characteristics Protective film B Consists of cyclic olefin resin (film thickness 50㎛) Appearance quality Scratch, stamped, pressed Scratch, stamped, pressed Scratch, stamped, pressed Good

As shown in Table 1 above, it can be seen that when the film is made by solvent casting using the acrylic resin and PMMA particles according to the present invention, haze, dynamic friction coefficient, and blocking evaluation are excellent.

Among the slip materials, EVONIK's R812, which is a silica material and has a small particle size, is responsible for the slip properties, and MX150, a PMMA material and a large particle size, is responsible for blocking properties. The acrylic film is very stacky, but some of the long molecular chain BMA is included to reduce the stacky properties.

Therefore, as these components are combined together, the acrylic film according to the present invention has excellent slip and blocking properties, so that the winding quality is good, the quality can be maintained over time, and the film produced using the acrylic film according to the present invention The polarizing plate of the invention can also be confirmed that the appearance quality is good.

Claims (5)

With respect to 100 parts by weight of the acrylic resin represented by the following formula (1), methyl methacrylate (Methyl Methacrylate) units 70 to 98 parts by weight, butyl methacrylate (Butyl Methacrylate) units consisting of 2 to 30 parts by weight of acrylic resin and polymethylmeth Acrylate {PMMA; Poly (methyl methacrylate)} is formed by a solvent casting method from an acrylic resin composition comprising particles of material, core-shell rubber particles (CSR) and silica particles,
The polymethyl methacrylate {PMMA; The particle diameter of the poly (methyl methacrylate)} material is 1 to 2.0 μm, and the content of the particle of the PMMA material for the acrylic resin composition is 100 to 1000 ppm,
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 acrylic resin composition, and the content of the silica particles is 0.005 parts by weight to 0.1 parts by weight with respect to 100 parts by weight of the acrylic resin composition Wealth,
An acrylic film characterized in that the coefficient of dynamic friction is 0.7 or less is provided on one side of the polarizer, and a protective film containing a cyclic olefin resin is provided on the other side of the polarizer.
[Formula 1]

a and b are 1 or more as an integer.
MMA-BMA
Here, MMA is a methyl methacrylate unit, and BMA is a butyl methacrylate unit.
delete delete According to claim 1,
An acrylic film characterized in that the solvent of the solvent casting is mixed with a halogenated hydrocarbon and alcohol is provided on one side of the polarizer, and a protective film containing a cyclic olefin resin is provided on the other side of the polarizer. Polarizer.


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