KR20180013621A - Polarizing plate and optical display apparatus comprising the same - Google Patents

Abstract

Provided are a polarizing plate including a protective film with excellent UV shielding performance in spite of including a small amount of UV absorber, and an optical display apparatus including the same. The polarizing plate comprises: a polarizer; and a first protective film formed on at least one surface of the polarizer, wherein the first protective film includes a uniaxially stretched film and a UV absorber, and an angle formed by an absorption axis of the polarizer and a stretching direction of the first protective film is 83° to 97°.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing plate and an optical display device including the polarizing plate.

The present invention relates to a polarizing plate and an optical display device including the same.

The polarizing plate is used on the upper surface and the lower surface of the liquid crystal display panel for the purpose of controlling the vibration direction of the light for visualizing the display pattern of the liquid crystal display device. The polarizer includes a polarizer and a protective film formed on at least one surface of the polarizer. As the protective film, a triacetyl cellulose (TAC) film may be typically used. TAC films are more expensive than conventional polymer films. In order to replace the TAC film, a (meth) acrylate based low cost polymer film including a polyester-based and a polymethacrylate (PMMA) film including a polyethylene terephthalate (PET) film and the like is used.

On the other hand, the liquid crystal of the liquid crystal display panel can be destroyed by UV. In addition, UV among the light emitted from the backlight unit may cause a problem of deforming the polarizer. Therefore, by incorporating a UV absorber in the protective film in the polarizing plate and lowering the UV transmittance, the above-described problems can be solved.

However, the UV absorber, which absorbs light having a wavelength of 380 nm or less, is often colored, for example, yellow, and the protective film may be colored when the protective film contains an excessive amount of UV absorber. This may increase the color value of the polarizer and make it unsuitable for application to a liquid crystal display device. Accordingly, there is a demand for a polarizing plate capable of enhancing the UV-CUT (UV-blocking) performance while minimizing the degradation of the color value of the protective film while containing a small amount of UV absorbing agent.

The background art of the present invention is described in Korean Patent Publication No. 2011-0014515.

It is an object of the present invention to provide a polarizing plate comprising a protective film excellent in UV shielding performance even if it contains a small amount of UV absorber.

Another object of the present invention is to provide a polarizing plate comprising a protective film having the same UV blocking performance but capable of minimizing degradation of hue value.

The polarizing plate of the present invention comprises a polarizer and a first protective film formed on at least one side of the polarizer, wherein the first protective film comprises a uniaxially stretched film, the first protective film comprises a UV absorber, The angle formed between the absorption axis of the polarizer and the uniaxial stretching direction of the first protective film may be in the range of 83 [deg.] To 97 [deg.].

The liquid crystal display device of the present invention may include the polarizing plate of the present invention.

The present invention provides a polarizing plate comprising a protective film excellent in UV shielding performance even if it contains a small amount of UV absorber.

The present invention provides a polarizing plate comprising a protective film having the same UV blocking performance but capable of minimizing degradation of hue value.

1 is an exploded perspective view of a polarizing plate according to an embodiment of the present invention.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

In the present specification, 'upper' and 'lower' are defined with reference to drawings, and 'upper' may be changed to 'lower' and 'lower' may be changed to 'upper' depending on viewing time.

In the present specification, 'nx', 'ny', and 'nz' refer to a refractive index in a three-component system (x-axis direction, y-axis direction and z-axis direction (thickness direction)) of a polyester film at a wavelength of 550 nm (refractive index). For example, the x-axis direction may be a machine direction (MD), and the y-axis direction may be a transverse direction (TD).

Hereinafter, a polarizing plate of one embodiment of the present invention will be described with reference to FIG. 1 is an exploded perspective view of a polarizing plate according to an embodiment of the present invention.

1, a polarizer 100 of an embodiment of the present invention includes a polarizer 110, a first protective film 120 formed on the upper surface of the polarizer 110, and a second protective film 120 formed on the lower surface of the polarizer 110. [ And may include a protective film 130.

The first protective film 120 is a uniaxially stretched film and the absorption axis 110a of the polarizer 110 forms an angle A with the uniaxial stretching direction 120a of the first protective film 120 is 83 ° To 97 [deg.]. In the above range, the transmittance of the polarizing plate with respect to other angles can be remarkably lowered to the light of 380 nm or less, and the transmittance to the light of 380 nm or less can be made equal even though the amount of the UV absorber is smaller, The color appearance of the film can be reduced. Specifically, the polarizing plate 100 according to the present embodiment may have a transmittance of 2% or less, 1% or less, specifically 0% to 2% or 0% to 1% with respect to light having a wavelength of 380 nm or less.

The polarizer 110 can polarize the light transmitted through the second protective film 130.

The polarizer 110 is made of a polyvinyl alcohol-based film and is not particularly limited as long as it is a polyvinyl alcohol-based film regardless of the manufacturing method. For example, the polarizer may be one produced by using a modified polyvinyl alcohol film such as a partially-formalized polyvinyl alcohol film or an acetoacetyl-modified polyvinyl alcohol film. Specifically, it can be produced by dyeing a polyvinyl alcohol film with iodine or a dichroic dye and stretching it in a machine direction (MD). Specifically, it is produced through a swelling process, a dyeing process, and a stretching process. Methods of performing each step are commonly known to those skilled in the art. In this case, the absorption axis 110a of the polarizer 110 is substantially parallel to the MD. Substantially parallel "means that the angle formed by the absorption axis 110a of the polarizer 110 and the MD is within a range of 0 to 7 degrees and includes not only parallel but also some errors. The thickness of the polarizer 110 may be 3 탆 to 30 탆, specifically 10 탆 to 20 탆. In the above range, it can be used for a polarizing plate.

The first protective film 120 may be formed on the upper surface of the polarizer 110 to protect the polarizer 110 and to provide additional functions to the polarizer 100 according to the present embodiment.

The first protective film 120 includes an UV absorbent to absorb UV light among light emitted from the backlight unit or the like and transmitted through the polarizer 110, thereby improving the reliability of the polarizer. Further, since the first protective film 120 includes the UV absorber, it is possible to prevent damages of the display element, for example, liquid crystal or the like due to UV in the external light. The UV absorber can absorb light having a wavelength of 380 nm or less, more specifically, a wavelength of 200 nm to 380 nm or less. The UV absorber may include a UV absorber capable of absorbing the light, but in particular a UV absorber containing at least one of triazine, phenol, benzotriazole, salicylic, benzophenone, oxamide, . ≪ / RTI > In general, the UV absorber that absorbs the light of the above wavelength has a yellowish hue, and when the first UV absorber is included in the first protective film, the first protective film may exhibit a color, and the UV absorber may also affect the polarizing plate. When the UV absorber is used, the transmittance with respect to UV light in the polarizing plate according to the present embodiment can be remarkably lowered, and the transmittance with respect to light having a wavelength of 380 nm or less can be equalized even with a smaller amount of UV absorber, The color appearance of the protective film can be reduced. The first protective film 120 may contain not more than 1% by weight, specifically more than 0% by weight and not more than 1% by weight of the UV absorber. Within this range, the transmittance of UV light can be lowered.

The first protective film 120 may be a film formed of an optically transparent resin. Specifically, the resin may be a film other than a cellulose-based film such as a triacetyl cellulose film, such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyester resin such as polybutylene naphthalate, A cyclic olefin polymer (COP), a polycarbonate resin, a polyether sulfone resin, a polysulfone resin, a polyamide resin, a polyimide resin, a non-cyclic polyolefin resin Based resin, a polyvinyl alcohol-based resin, a polyvinyl chloride-based resin, and a polyvinylidene chloride-based resin. More specifically, since the resin is made of a polyester resin, more specifically, a polyethylene terephthalate resin, the moisture permeability can be kept low to further improve the reliability.

The first protective film 120 may be a TD (transverse direction) uniaxially stretched film. Specifically, the first protective film 120 may be a film uniaxially stretched by TD after extruding the resin containing the UV absorber. The inventor of the present invention has found that when the first protective film 120 is a film produced by TD uniaxial stretching after extruding the resin containing UV absorber, the absorption axis 110a of the polarizer 110 and the first protective film 120, that is, TD, is in the range of 83 ° to 97 °, the effect of the present invention can be obtained.

The first protective film 120 has an angle formed by the TD of the first protective film with respect to the absorption axis of the reference polarizer having a degree of polarization degree of 99.99% installed in an optical display device (for example, V-7100) for transmittance measurement at a wavelength of 380 nm (B, unit:%) when the angle formed by the TD of the first protective film with respect to the absorption axis of the reference polarizer having a degree of polarization of 99.99% with respect to the transmittance (A, unit:%) (B / A) of 1.1 to 30, specifically 5 to 15, can be obtained. Within this range, there may be an effect of lowering the UV transmittance.

The first protective film 120 has a transmittance of 2% or less for light having a wavelength of 380 nm or less when the angle A between the uniaxial stretching direction 120a and the absorption axis 110a of the polarizer 110 is 45 °. 5%, specifically 2% to 4%. The first protective film 120 has a transmittance of 5% or less for light having a wavelength of 380 nm or less when the angle A between the uniaxial stretching direction 120a and the absorption axis 110a of the polarizer 110 is 0 °. 10%, specifically from 6% to 8%. Within this range, a UV transmittance increasing effect can be obtained.

The first protective film 120 is a high-magnification stretched film having an ultra-high retardation, and when the polarizing plate is attached to a liquid crystal display device, the occurrence of rainbow stains is inhibited, and image quality deterioration can be prevented. In an embodiment, the first protective film 120 has an in-plane retardation (Re) of the following formula 1 at a wavelength of 550 nm of 6,000 nm or more, specifically 8,000 nm or more, more specifically 8,000 nm to 12,000 nm, 10,100 nm to 12,000 nm . In the above range, when used as a protective film of a polarizer, it is possible to prevent occurrence of rainbow stains, to inhibit the light leakage phenomenon in which light leaks from the side, and to prevent a difference in retardation value from being increased by preventing a change in retardation value according to an incident angle .

<Formula 1>

Re = (nx - ny) xd

(Where nx and ny are refractive indexes in the x-axis and y-axis directions of the first protective film at a wavelength of 550 nm, respectively, and d is the thickness (unit: nm) of the first protective film).

The first protective film 120 may have a degree of biaxiality (NZ) of the following formula 2 at a wavelength of 550 nm of 1.8 or less, specifically 1.0 to 1.8, and may have a stain control effect by birefringence in the above range:

<Formula 2>

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

(Where nx, ny and nz are refractive indices in the x-axis, y-axis and z-axis directions of the first protective film at a wavelength of 550 nm, respectively).

The first protective film 120 may have a retardation difference (Rth) in the thickness direction of the following formula 3 at a wavelength of 550 nm of 15,000 nm or less, for example, 8,000 nm to 13,000 nm. In this range, There can be:

<Formula 3>

Rth = ((nx + ny) / 2 - nz) xd

(Where nx, ny and nz are refractive indices in the x-axis, y-axis and z-axis directions of the first protective film at a wavelength of 550 nm and d is the thickness (unit: nm) of the first protective film).

If the nx and ny are all less than 1.65 or both nx and ny are both 1.65 or more, the first protective film 120 may be protected It was confirmed that rainbow stains can occur due to birefringence due to a change in retardation value depending on the incident angle and wavelength when the film is used. In the first protective film 120 of the polarizing plate of the embodiment of the present invention, when either one of nx and ny is 1.65 or more, the effect of suppressing occurrence of rainbow stains can be remarkably increased. In one embodiment, nx is 1.65 or more, specifically 1.67 to 1.75, and ny may be 1.65 or less, specifically 1.45 to 1.60. In another embodiment, ny is 1.65 or more, specifically 1.67 to 1.72, more specifically 1.69 to 1.72, and nx may be 1.65 or less, specifically 1.45 to 1.60. At this time, the absolute value (| nx-ny |) of the difference between nx and ny should be 0.1 to 0.2, specifically 0.1 to 0.18, such as 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, The viewing angle can be further improved, and iridescence irregularities can be prevented from occurring.

The first protective film 120 may be uniaxially stretched only in TD without MD stretching. The TD stretching ratio may be 2 to 10, and the MD stretching ratio may be 1 to 1.1. The "MD stretching ratio of 1 to 1.1" means that the film is stretched while moving the film during MD stretching, except that it is inevitably stretched due to the mechanical movement of the film. In particular, Means a non-readable state. In the present specification, the term "stretching ratio" may mean a ratio of the stretching length to the stretching length of the film.

If the TD stretching ratio is less than 2, the first protective film may have a low retardation, which may cause irregular smearing when used in a liquid crystal display device and may be easily torn due to deterioration of physical properties of the film. If the TD stretching ratio is more than 10, Can be cut off. For example, the TD stretching ratio may be 3 to 8. The stretching can be carried out by at least one of dry stretching and wet stretching. The stretching temperature is (Tg-20) ° to (Tg + 50) °, specifically 70 ° C to 150 ° C Specifically from 80 캜 to 130 캜, more specifically from 90 캜 to 120 캜.

And then heat stabilizing the first protective film after stretching. The first protective film stretched at a high magnification has a restoring force that returns to the original state. The thermal stabilization step can maintain the thermal stability of the film by controlling the stress on the restoring force of the polyester film. The thermal stabilization step may include heating both ends of the TD of the drawn first protective film while moving the film to the MD. In this case, the first protective film is stretched at a relatively low stretching ratio relative to the stretching step. The TD stretching ratio may be more than 0 to 3 times, specifically 0.1 to 2 times, more specifically 0.1 to 1 time. The TD fixation of the film is performed only to the extent of preventing the restoring force of the film by high-rate stretching, and there is no substantial TD stretching effect on the polyester film (tension-relaxation). Heating during the thermal stabilization step may be performed at 100 ° C to 300 ° C, and the heating time may be performed for 1 second to 2 hours.

The first protective film 120 may have a thickness of 50 mu m to 300 mu m, specifically, 50 mu m to 200 mu m. In the above range, it can be used for a polarizing plate.

Although not shown in FIG. 1, the first protective film 120 may have functionality on the upper surface, including a functional coating layer, for example, a hard coating layer, an anti-reflection layer or an inner fingerprint layer. The functional coating layer may have a thickness of 1 占 퐉 to 10 占 퐉. In the above range, it can be used as a polarizing plate upon lamination to a polarizer.

Also, although not shown in FIG. 1, the first protective film 120 may further include a surface coating layer on the lower surface. In the case where the first protective film 120 is a polyester film, the surface is hydrophobic, and particularly when the polyethylene terephthalate film is used as the protective film, the hydrophobicity is increased. In order to use such a film as a polarizing plate, a surface modification that converts it to a hydrophilic property is required. The surface modification of the conventional cellulose-based film may not sufficiently modify the surface of the film or may damage the surface of the film using the sodium hydroxide-based surface modification method. To this end, a surface coating layer comprising the adhesive primer having hydrophobic and hydrophilic functional groups can be formed on the protective film. The primer having a hydrophobic and hydrophilic functional group may include, but is not limited to, a polyester-based resin, a polyvinyl acetate-based resin, or a combination thereof. By adding the surface coating layer, the mechanical properties of the protective film and the low moisture permeability are maximized, so that a high resistance to external harsh conditions can be added to the polarizing plate. Further, the surface coating layer is formed between the protective film and the polarizing plate, so that the adhesion between the protective film and the polarizing film can be improved.

The second protective film 130 may be formed on the lower surface of the polarizer 110 to increase the mechanical strength of the polarizer 100 and to protect the polarizer 110.

The second protective film 130 may have a viewing angle compensation function by forming the optical film 130 on one surface of the liquid crystal display panel and having a predetermined range of retardation. In an embodiment, the second protective film 130 may have an in-plane retardation (Re) of 40 nm to 60 nm at a wavelength of 550 nm. There may be an optimum image quality effect in the above range. The thickness of the second protective film 130 may be 25 占 퐉 to 500 占 퐉, specifically, 25 占 퐉 to 50 占 퐉. In the above range, it can be used for a polarizing plate.

As the second protective film 130, a transparent optical film may be a polyester-based or non-polyester-based film including polyethylene naphthalate, polybutylene naphthalate or the like, and the non-polyester- A polyimide-based, a polyolefin-based, a polyolefin-based, a polyolefin-based, a polyamide-based, a polyamide-based, a polyamide-based, Based film, a polyvinyl alcohol-based film, a polyvinyl chloride-based film, or a polyvinylidene chloride-based film.

The thickness of the polarizing plate 100 may be 25 占 퐉 to 500 占 퐉. In the above range, it can be used for a polarizing plate for a liquid crystal display. The polarizing plate may have a degree of polarization of 99.99% or more, for example, 99.99 to 99.999%, and a transmittance (for example, measured at a wavelength of 550 nm) of 40% or more, for example 40 to 80%. In the above-mentioned range, there may be no deterioration of the optical characteristics when the liquid crystal display device is mounted.

Although not shown in FIG. 1, the first protective film 120 and the second protective film 130 may be adhered to the polarizer 110 by an adhesive layer for a polarizer, respectively. The adhesive layer may include at least one of ordinary adhesives such as an aqueous adhesive, a pressure-sensitive adhesive, and a photocurable adhesive. Although not shown in FIG. 1, a pressure sensitive adhesive layer may be further formed on the lower surface of the second protective film 130 to enable the polarizing plate to be laminated on the liquid crystal display panel. The pressure-sensitive adhesive may be a pressure-sensitive adhesive, but is not limited thereto.

The optical display device of the present invention may include a liquid crystal display device including the polarizing plate of the embodiment of the present invention. The liquid crystal display device includes a liquid crystal display panel, a first polarizer formed on the upper surface of the liquid crystal display panel, a backlight unit formed on the lower surface of the liquid crystal display panel, a liquid crystal display panel formed on the lower surface of the liquid crystal display panel, And the first polarizing plate may include the polarizing plate of the embodiment of the present invention.

The liquid crystal display panel includes a liquid crystal panel including a liquid crystal cell layer sealed between a first substrate and a second substrate. In one embodiment, the first substrate includes a color filter (CF) substrate (upper substrate) (Thin Film Transistor) substrate (lower substrate). The first substrate and the second substrate may be the same or different, and may be a glass substrate or a plastic substrate. The plastic substrate is made of polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI), polyethylene naphthalate (PEN), polyether sulfone (PES), polyarylate (PAR) and cycloolefin copolymer (COC) Or the like, but the present invention is not limited thereto. The liquid crystal cell layer may be a liquid crystal cell layer including liquid crystal of VA (Vertical Alignment) mode, IPS (In Place Switching) mode, FFS (Fringe Field Switching) mode and TN (Twisted Nematic) mode.

The second polarizing plate may include a conventional polarizing plate.

The backlight unit is typically used in a liquid crystal display, and may include a light source, a light guide plate, a reflection plate, a diffusion plate, and the like.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Example  One

A polyvinyl alcohol film (VF-PS6000, manufactured by Kuraray Co., Ltd., thickness: 60 占 퐉) was stretched three times at 60 占 폚 and adsorbed to iodine and then stretched 2.5 times in an aqueous boric acid solution at 40 占 폚 to prepare a polarizer.

Extruding a composition comprising polyethylene terephthalate (PET) resin and CGX UVA 006 (Basf) as a UV absorber (UV absorber included in the composition is included in 1% by weight), mechanically moving the film using a roll in an MD, , Stretched 6 times in TD only without stretching, and subjected to tension-relaxation at 100 ° C to produce polyethylene terephthalate film 1.

The polyethylene terephthalate film 1 had a thickness of 80 占 퐉. At a wavelength of 550 nm, the Re of the formula 1 was 8,000 nm, the NZ of the formula 2 was 1.6, and the Rth of the formula 3 was 9,600 nm. Re, NZ and Rth were measured at a wavelength of 550 nm using a phase difference measuring apparatus (Axoscan, AxoMetric).

Specific specifications of the polyethylene terephthalate film 1 are shown in Table 1 below.

The polyethylene terephthalate film 1 had a yellow index (YI) of 1.8 when using D1925 light source and a * of -0.1 and b * of 0.9 when using D65 light source, as measured by CM-3600D (Konica Minolta). The polyethylene terephthalate film 1 was placed in a UV-VIS spectrometer (JASCO, V-7100) and the angle formed between the absorption axis of the reference polarizer having a polarization degree of 99.99% and the TD of the polyethylene terephthalate film 1 (B, unit: °) was changed as shown in Table 1, and the light transmittance at 380 nm to 800 nm, the light transmittance at 380 nm and the light transmittance at 380 nm measured at TD were measured. The light transmittance was measured at a wavelength of 380 nm. When measuring the light transmittance, color values as and bs were also obtained through V-7100. The results are shown in Table 1 below.

A triacetyl cellulose film (KC4DR-1, Konica Corp., thickness 40 占 퐉) was attached to one surface of the polarizer and the polyethylene terephthalate film 1 was coated on the other surface of the polarizer at an angle (A, unit: (Z-200, manufactured by Nippon Goshei) to prepare a polarizing plate. The angle is defined as an angle formed by the absorption axis of the prepared polarizer and the TD, which is the uniaxial stretching direction of the polyethylene terephthalate film.

Example  2

A polarizing plate was prepared in the same manner as in Example 1, except that the angle (A, unit: °) was changed as shown in Table 2 below.

Example  3

A polarizing plate was prepared in the same manner as in Example 1, except that the angle (A, unit: °) was changed as shown in Table 2 below.

Comparative Example  1 and Comparative Example  2

A polarizing plate was prepared in the same manner as in Example 1, except that the angle (A, unit: °) was changed as shown in Table 2 below.

Comparative Example  3

Except that a polyethylene terephthalate film 1 was replaced with a TAC film (KC4DR-1, Konica, thickness: 40 탆, including triazine as UV absorber, UV absorber content: 1 wt% in film, unoriented film) A polarizing plate was produced in the same manner. In case of TAC film, the angle (A, unit: °) can not be determined because it is a lead-free film.

The specific specifications of the TAC film were measured in the same manner as in Example 1 and are shown in Table 1 below.

Comparative Example  4

A composition (including 1 wt% of UV absorber in the composition) comprising the polyethylene terephthalate (PET) resin of Example 1 and a UV absorber (Tinuvin 326, Ciba) was melt-extruded and the MD stretching ratio 3 times, the TD stretching ratio 3 Followed by biaxial stretching to prepare a polyethylene terephthalate film 2 (thickness: 40 탆).

A polarizing plate was produced in the same manner as in Example 1, except that the polyethylene terephthalate film 2 was used instead of the polyethylene terephthalate film 1. In the case of the PET film 2, the angle (A, unit: °) can not be determined because it is a biaxially stretched film.

The specific specifications of the PET film 2 were measured in the same manner as in Example 1 and are shown in Table 1 below.

Angle
(B, °)

Optical property Color value Light transmittance (%) @ 380 nm to 800 nm
Light transmittance (%) Color value YI
a *
b *
Optical Transmittance @ 380nm MD light transmittance @ 380nm TD light transmittance @ 380nm as bs PET film 1

90 94.0 2.1 2.1 2.1 -0.3 0.8

1.8 -0.1


0.9
45 92.9 12.6 12.6 12.6 -0.3 0.5 0 92.2 20.8 20.8 20.8 -0.1 0.5 TAC film - 93.0 4.5 4.3 4.7 -0.1 0.3 One -0.1 0.5 PET film 2 - 91.9 3.1 3.1 3.1 -1.0 0.9 1.4 -0.7 0.8

The properties of the polarizing plates of Examples and Comparative Examples were evaluated in the following Table 2, and the results are shown in Table 2 below.

Optical characteristics and color values: The polarizing plate prepared in Examples and Comparative Example was irradiated with light at a wavelength of 380 nm or a wavelength of 380 nm to wavelength 800 nm with a UV-VIS spectrometer (JASCO Corporation, V-7100) So as to be transmitted through the film.

The kind of the first protective film Angle
(A, °) Optical property Light transmittance (%)
@ 380 nm to 800 nm Light transmittance (%) Color value Light transmittance
@ 380nm MD light transmittance @ 380nm TD light transmittance
@ 380nm as bs Example 1 PET film 1 90 42.4 0.7 1.4 0.0 -1.0 4.0 Example 2 PET film 1 83 42.4 0.7 1.4 0.0 -1.0 4.0 Example 3 PET film 1 97 42.4 0.7 1.4 0.0 -1.0 4.0 Comparative Example 1 PET film 1 45 42.1 3.8 7.5 0.0 -1.1 3.5 Comparative Example 2 PET film 1 0 42.0 6.8 13.7 0.0 -1.0 3.5 Comparative Example 3 TAC film - 42.4 0.6 1.2 0.0 -1.4 3.5 Comparative Example 4 PET film 2 - 42.5 2.6 5.2 0.0 -2.3 4.7

As shown in Table 2, the polarizing plate of the present invention was excellent in UV blocking performance even when a small amount of UV absorber was included.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (11)

A polarizer, and a first protective film formed on at least one surface of the polarizer,
Wherein the first protective film comprises a uniaxially stretched film,
Wherein the first protective film comprises a UV absorber,
And an angle formed by the absorption axis of the polarizer and the uniaxial stretching direction of the first protective film is 83 DEG to 97 DEG.
The polarizer according to claim 1, wherein the UV absorber absorbs light having a wavelength of 380 nm or less.
The polarizing plate according to claim 1, wherein the UV absorber comprises at least one of a triazine-based, phenol-based, benzotriazole-based, salicylic acid-based, benzophenone-based or oxamide-based UV absorber.
The polarizer of claim 1, wherein the UV absorber is contained in an amount of not more than 1% by weight of the first protective film.
The polarizing plate according to claim 1, wherein the first protective film comprises a film obtained by uniaxially stretching a resin film containing the UV absorbing agent in TD.
The method according to claim 1, wherein the first protective film has a transmittance (A) in a wavelength range of 380 nm when the angle formed between the TD of the first protective film and the absorption axis of the reference polarizer having a polarization degree of 99.99% Wherein a ratio (B / A) of the transmittance (B / A) when the angle formed by the TD of the first protective film to the absorption axis of the reference polarizer having a polarization degree of 99.99% is 0 ° is 1.1 to 30.
The polarizer according to claim 1, wherein the first protective film has a transmittance of 2% to 5% with respect to light having a wavelength of 380 nm or less when the angle formed by the uniaxial stretching direction and the absorption axis of the polarizer is 45 °. Polarizer.
The polarizing plate according to claim 1, wherein the first protective film has a transmittance of 5% to 10% with respect to light having a wavelength of 380 nm or less when the angle formed by the uniaxial stretching direction and the absorption axis of the polarizer is 0 °. Polarizer.
The polarizer of claim 1, wherein the first protective film is a non-cellulosic film.
The polarizing plate according to claim 1, wherein the first protective film is formed on one surface of the polarizer,
And a second protective film is formed on the other surface of the polarizer.
An optical display device comprising the polarizing plate according to any one of claims 1 to 10.

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