KR20140023825A - Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same - Google Patents
Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same Download PDFInfo
- Publication number
- KR20140023825A KR20140023825A KR20120090331A KR20120090331A KR20140023825A KR 20140023825 A KR20140023825 A KR 20140023825A KR 20120090331 A KR20120090331 A KR 20120090331A KR 20120090331 A KR20120090331 A KR 20120090331A KR 20140023825 A KR20140023825 A KR 20140023825A
- Authority
- KR
- South Korea
- Prior art keywords
- optical film
- acrylic
- meth
- polarizing plate
- film
- Prior art date
Links
Landscapes
- Polarising Elements (AREA)
Abstract
The present invention is an acrylic optical film formed of a resin composition comprising an alkyl (meth) acrylate unit, a benzyl (meth) acrylate unit, a (meth) acrylic acid unit, and a unit represented by the formula (I), wherein the thickness of the acrylic optical film d, when the impact energy value measured through the drop impact test of the acrylic optical film is IE, the expression (1) 0.03kg · m 2 / m 3 ≤ d × IE ≤ 0.18kg · m 2 / m 3 It relates to an acrylic optical film and a thin polarizing plate including the same.
Description
The present invention relates to an acrylic optical film and a polarizing plate including the same, and more particularly, to an acrylic optical film having excellent toughness and a polarizing plate including the same.
Recently, various display technologies such as a plasma display (PDP), a liquid crystal display (LCD), and an organic EL display (LED), which replace conventional CRTs, have been proposed and marketed according to the development of optical technology. On the other hand, various polymer films such as a polarizing film, a polarizer protective film, a retardation film, a light guide plate, and a plastic substrate are used for such display devices, and such a polymer material for displays has a tendency to be further improved.
Currently, the most widely used polymer film for displays is triacetyl cellulose (TAC), which is used as a protective film for polarizing plate. When the TAC film is used for a long time under a high temperature or high humidity atmosphere, the degree of polarization is lowered, There is a problem that the film is separated or the optical characteristic is deteriorated. In order to solve this problem, as an alternative to the TAC film, acrylic films such as polystyrene, methyl methacrylate, or polycarbonate-based polymer films have been proposed. These polymer films have an advantage in that they have excellent heat resistance. However, in the case of polystyrene or polycarbonate film, birefringence occurs at the orientation due to an aromatic ring in the polymer, which adversely affects the optical characteristics. Is not sufficient for application to optical materials such as liquid crystal devices in which the retardation value is relatively small compared to polystyrene or polycarbonate but high precision is required.
In order to solve this problem, acrylic films prepared by copolymerizing or blending monomers or polymers having positive birefringence and monomers or polymers having negative birefringence as materials for polymer films having excellent heat resistance and low retardation values are proposed. It became. Typical examples include an acrylic film made of a copolymer resin of benzyl methacrylate and methyl methacrylate.
However, the acrylic films proposed so far have advantages of excellent moisture resistance, durability, and low cost. However, since the toughness is lower than that of the TAC film, a polarizing plate using these acrylic films as a protective film is used for the liquid crystal panel. There is a problem that the polarizer is torn or broken in the process of attaching and detaching.
On the other hand, the conventional polarizing plate was composed of a structure for attaching a protective film on both sides of the polarizing element, but in recent years, a so-called thin polarizing plate for attaching a protective film only on one side of the polarizing element has been proposed. In the case of such a thin polarizing plate, the thickness of the thin polarizing plate is not only advantageous in that a slim image display device can be realized, but also an excellent optical characteristic can be realized by minimizing a phase difference inevitably caused by a protective film. . However, in the case of such a thin polarizing plate, since the protective film which becomes the support body of a polarizing element is attached only to one side, there exists a problem of being easy to be broken or broken compared with the polarizing plate with a protective film on both surfaces. In particular, this problem is more prominent when an acrylic film having a low toughness is used as a protective film.
The present invention is to solve the above problems, to provide an acrylic optical film excellent in optical properties, durability and toughness, which is not easily damaged even when used in a thin polarizing plate.
In addition, the present invention is to provide a thin polarizing plate comprising such an acrylic optical film.
To this end, the present invention is an acrylic optical film formed of a resin composition comprising an alkyl (meth) acrylate unit, a benzyl (meth) acrylate unit, a (meth) acrylic acid unit, and a unit represented by the following formula (I): When the thickness of the said acrylic optical film is d and the impact energy value measured through the drop impact test of the said acrylic optical film is IE, Equation (1) 0.03 kg * m <2> / m <3> d * IE <= 0.18 kg * The acrylic optical film which satisfy | fills m <2> / m <3> is provided.
(I)
In [Formula 1], X is NR 3 or O,
Wherein R 1 , R 2 And R 3 are each hydrogen, C 1 ~ 10 alkyl, C 3 ~ 20 cycloalkyl or C 3 ~ 20 aryl.
Meanwhile, the thickness d of the acrylic optical film is preferably about 20 μm to 80 μm, and the resin composition preferably has a weight average molecular weight of 100,000 to 200,000.
In another aspect, the present invention is a polarizer, the acrylic optical film of the present invention attached to one side of the polarizer; And it provides a thin polarizing plate comprising a pressure-sensitive adhesive layer formed on the other surface of the polarizer and an image display device comprising the same.
Since the acrylic optical film of the present invention is excellent in toughness, when the acrylic optical film of the present invention is applied to a thin polarizing plate, the effect of not being easily damaged in a step of attaching and detaching the polarizing plate to a liquid crystal panel, a so-called rework process. There is.
Hereinafter, the present invention will be described in more detail.
The inventors of the present invention have been studied to develop an acrylic optical film having excellent toughness properties, and formed with a resin composition containing a specific component, the thickness of the film d, measured by the drop impact test of the film When the impact energy value is IE, it was found that when the d × IE value satisfies a specific range, an acrylic optical film having excellent toughness can be produced, and thus the present invention was completed.
The acrylic optical film of the present invention is an acrylic optical film formed of a resin composition comprising an alkyl (meth) acrylate unit, a benzyl (meth) acrylate unit, a (meth) acrylic acid unit, and a unit represented by the following formula (I), wherein the acrylic When the thickness of the optical film is d and the impact energy value measured through the drop impact test of the acrylic optical film is IE, Equation (1) 0.03 kg · m 2 / m 3 ≤ d × IE ≤ 0.18 kg · m 2 It is characterized by satisfying / m 3 .
(I)
In this case, in [Formula 1], X is NR 3 or O, the R 1 , R 2 And R 3 are each hydrogen, C 1 ~ 10 alkyl, C 3 ~ 20 cycloalkyl or C 3 ~ 20 aryl group.
In this case, the resin composition forming the acrylic optical film of the present invention may be a copolymer resin in which each unit is included in the form of a repeating unit, or a blend resin in which monomers or homopolymers of the respective units are blended, Two or more copolymers of two or more units may be blended blend resins. Among them, it is particularly preferable that the quaternary copolymer resin contains the above-mentioned respective unit components in the form of a repeating unit.
In the resin composition, the alkyl (meth) acrylate unit means both alkyl acrylate and alkyl methacrylate, but is not limited thereto, in view of optical transparency, compatibility, processability and productivity, the alkyl It is preferable that carbon number of the alkyl group of (meth) acrylate is about 1-10, It is more preferable that it is about 1-4 carbon atoms, It is most preferable that it is a methyl group or an ethyl group. On the other hand, the content of the alkyl (meth) acrylate unit is preferably about 55 to 94 parts by weight, more preferably 60 to 90 parts by weight, most preferably 70 to 90 with respect to 100 parts by weight of the total resin composition. It may be part by weight. This is because excellent retardation characteristics and optical characteristics can be obtained when the content of the alkyl (meth) acrylate unit is in the above range.
In the above resin composition, the benzyl (meth) acrylate unit is for imparting a proper phase difference value to the optical film of the present invention and for providing compatibility between alkyl (meth) acrylate and (meth) acrylic acid, Benzyl methacrylate or benzyl acrylate, particularly benzyl methacrylate. On the other hand, the content of the benzyl (meth) acrylate unit is preferably about 2 to 20 parts by weight, more preferably about 2 to 18 parts by weight, based on 100 parts by weight of the total resin composition. This is because the desired retardation characteristics can be obtained when the content of benzyl (meth) acrylate is within the above range.
On the other hand, in the resin composition, the (meth) acrylic acid unit serves to improve the heat resistance and to introduce a polar group to lower the coefficient of thermal expansion, for example, acrylic acid, methacrylic acid, methylacrylic acid, methylmethacrylic acid , Ethylacrylic acid, ethyl methacrylic acid, butylacrylic acid or butyl methacrylic acid, particularly methacrylic acid. On the other hand, the content of the (meth) acrylic acid unit is preferably about 1 to 10 parts by weight, more preferably 1 to 5 parts by weight, most preferably 1 to 3 parts by weight based on 100 parts by weight of the total resin composition. Can be. When the content of the (meth) acrylic acid unit is within the above range, preferable heat resistance characteristics can be obtained. In particular, when the content of (meth) acrylic acid is 3 parts by weight or less, there is an additional advantage that the generation of bubbles in the film forming process can be significantly reduced.
On the other hand, in the resin composition, the unit represented by the formula (1) is for lowering the coefficient of thermal expansion of the resin composition. When a bulky functional group that inhibits polymer chain rotation is introduced into the polymer backbone, the coefficient of thermal expansion of the polymer can be lowered. However, for example, when using polymers containing bulky functional groups such as styrene or polycarbonate, the coefficient of thermal expansion may be lowered, but birefringence may be exhibited by stretching, which may cause problems in optical properties. However, when using the compound represented by the formula (1) as in the present invention, it is possible to effectively lower the coefficient of thermal expansion without adversely affecting the optical properties. Specific examples of the unit represented by the following formula (1) include glutaric acid anhydride and glutaric acid imide, and among them, glutaric anhydride is particularly preferable. On the other hand, the content of the unit represented by the formula (1) is preferably about 3 to 15 parts by weight based on 100 parts by weight of the total resin composition. When the content of the unit represented by the formula (1) is within the above range, it is possible to implement a low coefficient of thermal expansion without compromising the retardation characteristics.
In the resin composition for an optical film of the present invention comprising the above components, the glass transition temperature is preferably 100 ° C to 500 ° C, more preferably 110 ° C to 500 ° C, and most preferably 110 ° C to 200 ° C. desirable.
In addition, the weight average molecular weight of the resin composition is preferably 100,000 to 200,000. When the weight average molecular weight is less than 100,000, there is a problem that it is difficult to apply to the polarizing plate due to the lack of toughness of the optical film produced using the resin, and when the weight average molecular weight exceeds 200,000, the melt viscosity is high and the melt of the resin There is a problem that film appearance defects such as die line, gel, bubble, etc. are liable to occur during film production through extrusion.
Moreover, it is preferable that the transparency (haze) of the said resin composition is about 0.1 to 3%, and it is preferable that light transmittance is 90% or more. In addition, the yellow index value is preferably about 0.3 to 2.0. If the value is out of the above, the display color may change.
On the other hand, the resin composition may be prepared according to the copolymer resin production method or blend resin production method well known in the art. For example, the resin composition of the present invention may be formed by mixing monomers of respective components, followed by solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization, or a monomer or homopolymer resin of each component or a copolymer of two or more components May be prepared by blending the resin.
On the other hand, when the component of the formula (1) of the resin composition is glutaric anhydride, three components of alkyl (meth) acrylate, (meth) acrylic acid and benzyl (meth) acrylate without adding the component of the formula (1) The resin composition of this invention can also be manufactured by the method of block polymerization, or suspension polymerization, and heat processing. In this case, the alkyl (meth) acrylate and / or the benzyl (meth) acrylate and the (meth) acrylic acid undergo hydrolytic condensation reaction by heat to form a 4-membered copolymer while generating glutaric anhydride.
The acrylic optical film of the present invention may be prepared by stretching the resin composition in a film form according to a method well known in the art such as a solution caster method or an extrusion method. In view of economics, it is more preferable to use an extrusion method. In some cases, during the film production process, an additive such as a modifier may be further added within a range that does not impair the physical properties of the film.
In the meantime, the stretching is in the longitudinal direction (MD). It is preferably carried out by biaxial stretching of 1.4 to 3 times and 1.4 to 3.0 times in the transverse direction (TD). When the draw ratio is less than 1.4 times, the toughness of the film is lowered, so that it is difficult to apply to the polarizing plate. When the draw ratio exceeds 3 times, there is a problem that stable film production is impossible due to the breakage of the film in the stretching process.
On the other hand, the stretching step may be performed in the longitudinal direction (MD) stretching, transverse direction (TD) stretching, or both may be performed. In the case of performing both the longitudinal drawing and the transverse drawing, either one of them may be stretched in the other direction, or the two directions may be stretched at the same time. In addition, the stretching may be performed in one step or may be performed in multiple steps. In the case of longitudinal stretching, stretching by the speed difference between rolls can be performed, and in the case of transverse stretching, tenter can be used. The time of railing of the tenter is usually within 10 degrees, thereby suppressing the bowing phenomenon occurring in the transverse direction drawing and controlling the angle of the optical axis regularly. Even when the transverse stretching is performed in multiple stages, the effect of inhibiting the bowing can be obtained.
On the other hand, the stretching is preferably carried out at (Tg-20) ℃ ~ (Tg + 30) ℃ when the glass transition temperature of the resin composition for producing the optical film is Tg, more preferably Tg ~ It is carried out at a temperature of Tg + 20 ° C. Tg-20 ° C is a temperature at which the storage modulus of the resin composition begins to decrease, and thus the loss modulus becomes larger than the storage modulus, and from this temperature to Tg + 30 ° C, which is a temperature at which the orientation of the polymer chain is relaxed and lost. It is preferably carried out in the region. However, considering stable film production and film toughness, it is more preferably carried out at a temperature of Tg ~ Tg + 20 ℃. The glass transition temperature of the resin composition can be measured by a differential scanning calorimeter (DSC).
The stretching speed is preferably in the range of 1 to 100 mm / min in the case of a small stretching machine (lab. Simultaneous biaxial stretching machine) and in the range of 0.1 to 2 m / min in the case of pilot stretching equipment. .
In the acrylic optical film of the present invention manufactured by the above method, when the thickness of the acrylic optical film is d, and the impact energy value measured through the drop impact test of the acrylic optical film is IE, the expression (1) 0.03 kg M 2 / m 3 ≤ d x IE ≤ 0.18 kgm 2 / m 3 is satisfied. As a result of the experiment, when the acrylic optical film satisfies the above formula (1), the acrylic optical film was applied to the polarizing plate, and then the acrylic optical film had a property of not easily being broken or broken in the rework process of attaching and detaching the polarizing plate to the liquid crystal panel.
In the present invention, the drop impact test uses a drop impact tester to drop a metal ball having a diameter of 15.9 mm and a weight of 16.3 g to a test target film to increase the maximum drop height immediately before the film is broken. The impact energy value IE was calculated by converting the impact energy per unit volume of the film from the maximum drop height obtained by the method.
In addition, the acrylic optical film of the present invention has a thermal expansion coefficient of about 50 to 70 ppm / K, and has a lower thermal expansion coefficient than that of the conventional acrylic film. As described above, since the coefficient of thermal expansion is low, when the optical film of the present invention is applied to a polarizing plate, curling can be suppressed.
Moreover, it is preferable that the thickness of the acrylic optical film of this invention is 20-100 micrometers, More preferably, it is about 20-80 micrometers. When the thickness of the film is less than 20 μm, the handleability of the film and the polarizing plate is poor, causing problems such as bending and breaking during the manufacturing process and the handling of the product. There is.
In addition, the acrylic optical film of the present invention has a transparency of about 0.1 to 3%, it is preferable that the light transmittance is 90% or more. It is because it is suitable to be used as a polarizing plate protective film when the thickness, transparency, and transmittance of a film exist in the said range.
On the other hand, the present invention provides a polarizer and a polarizing plate comprising the acrylic optical film of the present invention on at least one surface of the polarizer. At this time, the acrylic optical film may be attached to both surfaces of the polarizer, or may be attached only to one surface. Especially, the thin polarizing plate which attaches the acryl-type optical film of this invention to the single side | surface of a polarizer, and provided the adhesion layer on the other side of a polarizer is preferable.
On the other hand, the attachment of the polarizer and the optical film and / or protective film of the present invention, after coating the adhesive on the surface of the film or polarizer using a roll coater, gravure coater, bar coater, knife coater or capillary coater, etc. , The protective film and the polarizer may be carried out by laminating by heating with a lamination roll, or laminating by pressing at room temperature. As the adhesive, adhesives used in the related art, for example, a polyvinyl alcohol adhesive, a polyurethane adhesive, an acrylic adhesive and the like may be used without limitation.
In another aspect, the present invention relates to an image display device including the polarizing plate of the present invention. In this case, the image display device may be, for example, a liquid crystal display (LCD), a plasma display (PDP), an electroluminescent device (LED), or the like.
Hereinafter, the present invention will be described more specifically by way of specific examples. The following examples are given for the purpose of helping to understand the present invention, but the scope of the present invention is not limited thereto.
In the present invention, the physical property evaluation method is as follows.
1. Resin composition: measured using C13-NMR
2. Weight average molecular weight (Mw): The prepared resin was dissolved in tetrahydrofuran and measured by gel osmosis chromatography (GPC).
3. Glass transition temperature (Tg): Measured using a differential scanning calorimeter (DSC) of TA Instrument.
4. Film Impact Energy (IE): Using Withlab's Drop impact tester, drop a 15.9mm diameter and 16.3g iron ball onto the film to increase the maximum drop height just before the film breaks. The impact energy per unit volume of the film was calculated.
5. Polarizer Rework: A 100 mm × 20 mm sized polarizing plate was attached to an alkali free glass having a thickness of 0.7 mm, and stored at room temperature for 24 hours to determine whether the polarizing plate was broken when the polarizing plate was peeled off the glass. For the polarizing plate specimens, a total of ten specimens each of five specimens cut in the direction of the absorption axis of the polarizer and five specimens cut in the direction perpendicular to the absorption axis were evaluated, and the reworkability evaluation results were described based on the following criteria.
OK: All 10 specimens are peeled clean without being destroyed
NG: At least one of ten specimens destroyed
6. Film Stretch Breakability: The presence or absence of breakage in the process of stretching the film using a biaxial stretching machine was confirmed. Ten fracture specimens were subjected to extension fracture evaluation, and the results of extension fracture evaluation were described according to the following criteria.
OK: All 10 specimens are drawn without breaking
NG: at least one of ten specimens is broken
7. Polarizing plate polarization: Using N & K Technology's N & K Spectrometer, transmittance (orthogonal transmittance) in which the absorption axes of two polarizers are parallel to each other (parallel transmittance, Tp) in parallel with each other. , Tc) was measured and the polarization degree P was calculated using the following formula.
Polarization degree (P) = ((Tp-Tc) / (Tp + Tc)) 1/2 × 100 (%)
8. Contrast Ratio of LCD Panel: LG Display's IPS Mode 32-inch LCD panel peels off the polarizer that is already bonded and attaches the polarizer of the present invention. Measured using 210. From this, the contrast ratio was calculated using the following equation.
Contrast Ratio (CR) = the amount of light in the white display state / the amount of light in the black display state
Manufacturing example 1: Resin (A)
82 weight part of methyl methacrylate monomers, 8 weight part of benzyl methacrylate monomers, and 10 weight part of methacrylic acid monomers are mixed with toluene which is a polymerization solvent, and 0.03 weight part of dicumyl peroxide which is an initiator with respect to 100 weight part of this mixed solution. , 0.5 part by weight of t-dodecylmercaptan as a molecular weight regulator, and 0.2 part by weight of Irganox 245 as an antioxidant were prepared to prepare a polymerization solution.
The polymerization solution was polymerized at 145 ° C. for 2 hours by continuous bulk polymerization, followed by devolatilization of unreacted monomers and solvents in a volatilization tank at 250 ° C. and a vacuum of 20 torr, followed by methyl methacrylate unit, benzyl methacrylate unit, and methacrylic acid. Resin (A) containing units and glutaric anhydride units was prepared in pellet form. The composition, weight average molecular weight, and glass transition temperature of the prepared resin (A) were measured, and the results are shown in [Table 1].
Manufacturing example 2: resin (B)
Resin (B) was prepared in the same manner as in Preparation Example 1, except that 0.8 parts by weight of t-dodecyl mercaptan, which was a molecular weight regulator, was used. The composition, weight average molecular weight, and glass transition temperature of the prepared resin (B) were measured, and the results are shown in [Table 1].
Manufacturing example 3: resin (C)
Resin (C) was prepared in the same manner as in Production Example 1, except that 90 parts by weight of methyl methacrylate monomer, 5 parts by weight of cyclohexyl methacrylate monomer, and 5 parts by weight of phenyl maleimide monomer were used. The composition, weight average molecular weight, and glass transition temperature of the prepared resin (C) were measured, and the results are shown in [Table 1].
Polymerization solution
Copolymer
ingredient
< Example 1>
The resin (A) prepared in Preparation Example 1 was prepared using a T-die extruder to produce a film having a thickness of 185 μm, and then drawn at a ratio of 1.8 times the MD and TD directions at a temperature higher than 3 ° C. above the glass transition temperature of the resin. Biaxial stretching was performed to prepare an optical film having a thickness of 50 μm. The impact energy of the prepared film was measured and the results are shown in [Table 2]. The fracture phenomenon in the film processing did not occur.
A modified PVA-based aqueous adhesive was injected between the optical film of the present invention and the PVA polarizer having a thickness of 18 μm prepared by the above method, and then compressed using a pressing roll, followed by hot air drying at a temperature of 70 ° C. for 5 minutes to prepare a semi-polarizing plate. It was. A PET release film coated with a 13 μm-thick adhesive on the polarizer side of the manufactured polarizer semifinished product was laminated using a roll laminator, and a PET protective film was laminated on the opposite side of the optical film of the present invention to prepare a finished polarizer. . The reworkability evaluation of the polarizing plate thus produced was carried out, and the results are shown in [Table 2].
< Example 2>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that the stretching temperature was Tg + 8 ° C. Their main physical properties were measured and the results are shown in [Table 2].
< Example 3>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that the stretching temperature was Tg + 13 ° C. Their main physical properties were measured and the results are shown in [Table 2].
< Example 4>
An optical film and a polarizing plate were prepared in the same manner as in Example 1 except that the film before stretching was 150 μm, the stretching temperature was Tg + 8 ° C., and the stretching ratio was 1.6 times. Their main physical properties were measured and the results are shown in [Table 2].
< Example 5>
An optical film and a polarizing plate were prepared in the same manner as in Example 1 except that the film before stretching was 225 μm, the stretching temperature was Tg + 8 ° C., and the stretching ratio was 2.0 times. Their main physical properties were measured and the results are shown in [Table 2].
< Example 6>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that the film before stretching was 375 µm, the stretching temperature was Tg + 13 ° C., and the stretching ratio was 2.4 times. Their main physical properties were measured and the results are shown in [Table 2].
< Example 7>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that the film before stretching was 110 μm and the stretching temperature was Tg + 8 ° C. Their main physical properties were measured and the results are shown in [Table 2].
< Comparative Example 1>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that Resin (B) was used instead of Resin (A). Their main physical properties were measured and the results are shown in [Table 3].
< Comparative Example 2>
An optical film and a polarizing plate were manufactured in the same manner as in Comparative Example 1 except that the stretching temperature was Tg + 8 ° C. Their main physical properties were measured and the results are shown in [Table 3].
< Comparative Example 3>
An optical film and a polarizing plate were manufactured in the same manner as in Comparative Example 1 except that the stretching temperature was Tg + 13 ° C. Their main physical properties were measured and the results are shown in [Table 3].
< Comparative Example 4>
An optical film and a polarizing plate were manufactured in the same manner as in Example 1 except that Resin (C) was used instead of Resin (A). Their main physical properties were measured and the results are shown in [Table 3].
< Comparative Example 5>
An optical film and a polarizing plate were manufactured in the same manner as in Comparative Example 4 except that the stretching temperature was Tg + 8 ° C. Their main physical properties were measured and the results are shown in [Table 3].
< Comparative Example 6>
An optical film and a polarizing plate were manufactured in the same manner as in Comparative Example 4 except that the stretching temperature was Tg + 13 ° C. Their main physical properties were measured and the results are shown in [Table 3].
(kgm / m 3 )
(kgm 2 / m 3 )
Reference Example
The polarizing plate was manufactured using the optical film manufactured in Example 1 as follows. First, the optical film is placed on one surface of a 25 μm thick PVA polarizer, and a 60 μm thick TAC film (Fuji, UZ TAC) is placed on the other side, and thereafter, a modified PVA-based aqueous adhesive is injected therebetween, using a compression roll. After pressing, hot air was dried at a temperature of 80 ° C. for 5 minutes to prepare a semi-polarizing plate. After the corona treatment was performed on the acrylic film surface of the manufactured semi-finished polarizer plate under the condition of 50 W / m 2 · min, the PET release film coated with a 20 μm thick adhesive was laminated using a roll laminator, and the TAC film surface, which is the opposite side, was laminated. In the PET protective film was laminated to produce a finished polarizing plate. The polarization degree of the polarizing plate thus prepared and the contrast ratio after attaching it to the liquid crystal panel were measured and compared with the polarizing plate prepared in Example 2, that is, and the results are shown in [Table 4].
As can be seen from the above [Table 4], the optical film of the present invention is applied to a thin polarizing plate in which a protective film is formed only on one surface of the polarizer to exhibit excellent polarization degree and optical properties.
Claims (11)
When the thickness of the said acrylic optical film is d and the impact energy value measured through the drop impact test of the said acrylic optical film is IE, Formula (1) 0.03 kg * m <2> / m <3> d * IE <= 0.18 kg * Acrylic optical film satisfying m 2 / m 3 .
(I)
In [Formula 1], X is NR 3 or O,
Wherein R 1 , R 2 And R 3 are each hydrogen, C 1 ~ 10 alkyl, C 3 ~ 20 cycloalkyl or C 3 ~ 20 aryl.
Thickness d of the said acrylic optical film is 20 micrometers-100 micrometers acrylic optical film.
The resin composition is an acrylic optical film having a weight average molecular weight of 100,000 to 200,000.
The resin composition may comprise 55 to 94 parts by weight of alkyl (meth) acrylate units, 2 to 20 parts by weight of benzyl (meth) acrylate units, and 1 to 10 parts by weight of (meth) acrylic acid units; And 3 to 15 parts by weight of the acrylic optical film comprising a unit represented by the formula (I).
Said alkyl (meth) acrylate unit is methyl methacrylate, The acrylic optical film.
The benzyl (meth) acrylate unit is benzyl methacrylate acrylic optical film.
The (meth) acrylic acid unit is an acrylic optical film selected from the group consisting of acrylic acid, methacrylic acid, methyl acrylic acid, methyl methacrylic acid, ethyl acrylic acid, ethyl methacrylic acid, butyl acrylic acid and butyl methacrylic acid.
The unit represented by the formula (I) is an acrylic optical film that is glutaric anhydride.
The acrylic optical film is an acrylic optical film having a thermal expansion coefficient of 50 ~ 70ppm / ℃.
Acrylic optical film of any one of claims 1 to 10 attached to one surface of the polarizer; And
A thin polarizing plate comprising a pressure-sensitive adhesive layer formed on the other surface of the polarizer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR20120090331A KR20140023825A (en) | 2012-08-17 | 2012-08-17 | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR20120090331A KR20140023825A (en) | 2012-08-17 | 2012-08-17 | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020150102482A Division KR101627975B1 (en) | 2015-07-20 | 2015-07-20 | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20140023825A true KR20140023825A (en) | 2014-02-27 |
Family
ID=50269134
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR20120090331A KR20140023825A (en) | 2012-08-17 | 2012-08-17 | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR20140023825A (en) |
-
2012
- 2012-08-17 KR KR20120090331A patent/KR20140023825A/en active Application Filing
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3054322B1 (en) | Resin composition for optical film, optical film formed using same, and polarizing plate and image display device comprising same | |
| KR101105423B1 (en) | Optical film and information technology apparatus comprising the same | |
| KR101091534B1 (en) | Optical film and information technology apparatus comprising the same | |
| KR101279612B1 (en) | Polarizing plate and liquid crystal display comprising the same | |
| KR101269673B1 (en) | Resin composition for optical film and optical film using the same | |
| KR101409208B1 (en) | Method for synthesizing a resin composition for optical film using continuous bulk polymerization and method for manufacturing an optical film and polarizing plate using the same | |
| US10392458B2 (en) | Resin blend | |
| KR101377203B1 (en) | Preparation of resin composition for optical film using acryl based resin | |
| JP7153657B2 (en) | A transparent film based on a resin component with a high glass transition temperature | |
| KR101304588B1 (en) | Acryl-based copolymers and an optical film comprising the same | |
| TWI500685B (en) | Resin composition for optical film and optical film using the same | |
| JP4849115B2 (en) | Laminated body, liquid crystal display device and manufacturing method thereof | |
| KR101521682B1 (en) | Optical film having improved storage stability at a low temperature and a polarizing plate comprising the same | |
| KR101627975B1 (en) | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same | |
| KR101514111B1 (en) | Optical film having improved stability at a high temperature and a polarizing plate comprising the same | |
| KR101477847B1 (en) | Acryl-based copolymers for an optical film, and an optical film comprising the same | |
| KR20140023825A (en) | Acryl-based optical film having excellent toughness and slim polarizing plate comprising the same | |
| KR101497183B1 (en) | Acryl-based copolymer and optical film comprising the same | |
| KR101226935B1 (en) | Optical film comprising acryl-based resin, and liquid-crystal-display comprising the same | |
| KR101497182B1 (en) | Acryl-based copolymer and optical film comprising the same | |
| KR101565629B1 (en) | Resin composition for optical film and optical film using the same | |
| KR101522074B1 (en) | Optical film, method for manufacturing the same, polarizer and display device using the same | |
| KR20150033514A (en) | Optical film, method for manufacrueing the same, polarizing plate and display device comprising the same | |
| KR20130083658A (en) | Resin composition for optical film, protection film comprising the same and liquid crystal displaty |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A201 | Request for examination | ||
| E902 | Notification of reason for refusal | ||
| AMND | Amendment | ||
| E601 | Decision to refuse application | ||
| AMND | Amendment | ||
| A107 | Divisional application of patent |