KR20130074667A - Polarizer plate and optical display device comprising the same - Google Patents

Abstract

PURPOSE: A polarizing plate for an organic light-emitting device and an organic light-emitting display device including the same are provided to reduce external light reflection rate without the influence in organic luminescent materials and to increase the efficiency of an organic luminescent material blue light-emitting body. CONSTITUTION: A polarizing plate for an organic light-emitting device (100) comprises a polarizer (11), a protection film (13) which is laminated on one surface of the polarizer, and an adhesion layer (14) which is laminated on the other surface of the polarizer. The adhesion layer comprises an ultraviolet (UV) absorber.

Description

Polarizer plate for organic light emitting device and organic light emitting device display device including the same

The present invention relates to a polarizing plate for an organic light emitting device and an organic light emitting display device including the same. More specifically, the present invention minimizes the reflection of external light, reduces the reflectance, there is no color shift, color purity of the organic light emitting material, and in particular the organic light emitting device polarizing plate that can improve the luminous efficiency of the organic light emitting material and includes the same An organic light emitting display device is provided.

The organic light emitting diode display device requires a reflecting plate of anode / cathode for self emission. In general, when light is introduced from the outside, the light is sequentially incident on the polarizing plate and the retardation film, and is reflected back by the electrode unit constituting the organic light emitting diode in the organic light emitting diode display. Due to the reflected light, when the user looks at the organic light emitting diode display, problems such as glare, color shift, and contrast deterioration may occur.

On the other hand, the OLED panel of the organic light emitting material has a self-luminous body that emits light of its own R (red), G (green), B (blue) region. In order to increase the efficiency of the organic light emitting device, it should not affect the organic light emitting body. Conventionally, there was a method of preventing reflection of external light by using a λ / 4 compensation film and a dye, but the dye has a wide absorption wavelength width, which affects an organic light emitting material, causing color shift, color purity, and luminous efficiency. Can be. In particular, the blue emitter of the self-illuminator should not cause a decrease in efficiency because of the shortest lifetime among the OLED emitters. In addition, when using a dye shifted to a short wavelength in order not to affect the organic light emitting material it may increase the reflection of the external light.

An object of the present invention is to provide a polarizing plate for an organic light emitting device that can reduce the external light reflectance without affecting the organic light emitting material.

Another object of the present invention is to provide a polarizing plate for an organic light emitting device that can increase the efficiency of the organic light emitting material blue light emitting body.

Still another object of the present invention is to provide an organic light emitting display device including the polarizing plate for the organic light emitting device.

Polarizing plate for an organic light emitting device which is an aspect of the present invention is a polarizer; A protective film laminated on one surface of the polarizer; And a pressure-sensitive adhesive layer laminated on the other side of the polarizer, and the pressure-sensitive adhesive layer may include a UV absorber.

Another aspect of the present invention, a polarizing plate for an organic light emitting device includes a polarizer; An adhesive layer laminated on one surface of the polarizer; And a protective film and a UV absorbing layer stacked on the other side of the polarizer, wherein the protective film and the UV absorbing layer may include a UV absorber having an absorption wavelength of 450 nm or less.

An organic light emitting diode display according to another aspect of the present invention may include the polarizing plate for the organic light emitting diode.

The present invention provides a polarizing plate for an organic light emitting device that can reduce the external light reflectance without affecting the organic light emitting material. The present invention provides a polarizing plate for an organic light emitting device that can increase the efficiency of the organic light emitting material blue emitter. The present invention provides an organic light emitting display device comprising the polarizing plate for the organic light emitting device.

1 to 4 show cross-sectional views of specific examples of the polarizing plate for an organic light emitting device of the present invention.
Figure 5 shows the reflectance according to the wavelength of the polarizing plate of Example 1-4 and Comparative Example 1.

Polarizing plate for an organic light emitting device which is an aspect of the present invention may include a polarizer, a protective film and the adhesive layer optionally UV absorbing layer, and may include a UV absorber.

The UV absorber may have an absorption wavelength of 450 nm or less, preferably 430 nm or less. Within this range, it is possible to improve the luminous efficiency of the blue series, and to prevent a decrease in luminance. Preferably, the UV absorber may have an absorption wavelength of 300 nm-430 nm, more preferably 420 nm-430 nm.

The UV absorber can be selected from the group consisting of benzotriazoles, benzophenones, triazines, benzimidazoles, and mixtures thereof. Preferably, a benzotriazole UV absorber or a mixture containing the same may be used.

Such a UV absorber may be included in one or more of an adhesive layer, a protective film, and a UV absorbing layer of the polarizing plate.

In one embodiment, the UV absorber may be included in the adhesive layer of the polarizing plate. The adhesive layer may include a UV absorber and an adhesive resin.

The adhesive resin may be selected from the group consisting of (meth) acrylic, urethane, polyisobutylene, styrene butadiene rubber, polyvinyl ether, epoxy, melamine, polyester, phenol, silicone, and mixtures thereof. have. Preferably, (meth) acrylic resin can be used.

In the adhesive layer, the UV absorber may be included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the adhesive resin. Within this range, black frontal reflection can be obtained while increasing the blue light emission efficiency by decreasing the blue luminance reduction rate. Preferably it may be included in 5-10 parts by weight.

An adhesion layer can be formed in a polarizer or a retardation film using a conventional method. The adhesive resin and the UV absorber are mixed and coated on one surface of the polarizer or the retardation film to form an adhesive layer.

The thickness of the adhesive layer may be 10 μm-100 μm. Preferably it may have a thickness of 10㎛-40㎛.

In other embodiments, the UV absorber may be included in the protective film. The protective film may include a protective film-forming resin and a UV absorber.

As the resin for forming the protective film, a resin capable of forming a conventional protective film can be used. For example, the resin for forming a protective film may be a cellulose type, a polyester type, a cyclic polyolefin type, a polycarbonate type, a polyether sulfone type, a polysulfone type, a polyamide type, a polyimide type, a polyolefin type, a polyarylate type, Polyvinyl alcohol-based, polyvinyl chloride-based, polyvinylidene chloride-based, and mixtures thereof.

In the protective film, the UV absorber may be included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the resin for forming the protective film. Within this range, black frontal reflection can be obtained while increasing the blue light emission efficiency by decreasing the blue luminance reduction rate. Preferably it may be included in 5-10 parts by weight.

A protective film can be formed using a conventional method for a polarizer. The protective film-forming resin and the UV absorber are mixed and coated on a release film. After drying, the release film may be removed and laminated on the polarizer, but is not limited thereto.

The thickness of the protective film may be 10 占 퐉 to 100 占 퐉. Preferably it may have a thickness of 50㎛-100㎛.

In another embodiment, the UV absorber may be included in the UV absorber layer. The UV absorbing layer may include a resin for forming a film and a UV absorber.

Resin for film formation is cellulose type, polyester type, cyclic polyolefin type, polycarbonate type, polyether sulfone type, polysulfone type, polyamide type, polyimide type, polyolefin type, polyarylate type, polyvinyl alcohol type, Polyvinyl chloride-based, polyvinylidene chloride-based, and mixtures thereof.

In the UV absorbing layer, the UV absorbing agent may be included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the resin for forming a film. In the above range, it is possible to obtain a black front reflection test while lowering the blue luminance reduction rate and increasing the blue light emission efficiency by increasing the transmittance. Preferably it may be included in 5-10 parts by weight.

In one embodiment, the polarizer comprises a polarizer; A protective film laminated on one surface of the polarizer; And an adhesive layer laminated on the other surface of the polarizer, and the adhesive layer may include a UV absorber.

In another embodiment, the polarizing plate for an organic light emitting device comprises a polarizer; An adhesive layer laminated on one surface of the polarizer; And a protective film and a UV absorbing layer stacked on the other side of the polarizer, wherein the protective film and the UV absorbing layer may include a UV absorber.

In the polarizing plate, a phase difference film may be further laminated between the polarizer and the adhesive layer. The retardation film can adjust the optical characteristics of the light to adjust the phase difference or to improve the viewing angle. The retardation film is a lambda / 4 retardation film. It serves to change the linear polarization to circular polarized light or to convert circular polarized light to linear polarized light by providing a phase difference of? / 4 to two mutually perpendicular polarization components parallel to the optical axis of the retardation film do. The retardation film changes the light resistance of the organic light emitting diode display device from circularly polarized light to linearly polarized light or changes linearly polarized light to circularly polarized light.

The retardation film may be a film having an in-plane retardation value of 550 nm to 130 nm-150 nm.

The retardation film is generally used in a polarizing plate for an organic light emitting element, and can be used without limitation as long as the film has a retardation function. As the retardation film, a film made of cycloolefin polymer (COP), acrylic, cellulose, olefin or a mixture thereof can be used. Preferably, a cycloolefin polymer film can be used.

The thickness of the retardation film may be 10 μm-100 μm. Within this range, it is possible to provide an optical compensation effect when used in a polarizing plate, and to phase-inject incident light by a delay value of λ / 4. Preferably it may have a thickness of 10㎛-50㎛.

In the polarizing plate, a functional film may be further laminated on one surface of the protective film. The functional film is laminated on the protective film to impart functionality to the protective film. The functional film may include, for example, a low reflection film, an antiglare film, an antiglare and antireflective composite film, a hard coat film, or a mixture thereof.

1 illustrates a cross-sectional view of a polarizing plate according to an embodiment of the present invention. According to FIG. 1, the polarizing plate 100 includes a polarizer 11, a protective film 13 laminated on one surface of the polarizer, a retardation film 12 laminated on the other surface of the polarizer, and an adhesive layer laminated on one surface of the retardation film ( 14). The adhesive layer may include a UV absorber.

Figure 2 shows a cross-sectional view of a polarizing plate according to another embodiment of the present invention. According to FIG. 2, the polarizing plate 100 ′ includes a polarizer 11, a protective film 13 laminated on one surface of the polarizer, a functional film 15 laminated on one surface of the protective film, and a phase difference film laminated on the other surface of the polarizer. 12, an adhesive layer 14 laminated on one surface of the retardation film may be included. The adhesive layer may include a UV absorber. The functional film can be, for example, a low reflection film.

Figure 3 shows a cross-sectional view of a polarizing plate according to another embodiment of the present invention. According to FIG. 3, the polarizer 200 includes a polarizer 21, a protective film 23 laminated on one surface of the polarizer, a retardation film 22 laminated on the other surface of the polarizer, and an adhesive layer laminated on one surface of the retardation film ( 24). The protective film may include a UV absorber.

Figure 4 shows a cross-sectional view of a polarizing plate according to another embodiment of the present invention. According to FIG. 4, the polarizing plate 300 includes a polarizer 31, a protective film 33 laminated on one surface of the polarizer, a UV absorbing layer 36 stacked on the protective film, and a phase difference film 32 laminated on the other surface of the polarizer. The adhesive layer 34 may be stacked on one surface of the retardation film. The UV absorber layer may comprise a UV absorber.

The polarizer aligns the direction of the light passing through the retardation film and divides the incident light into two polarizing components orthogonal to each other, passing only one component and absorbing or dispersing the other component.

The polarizer can be used without limitation as long as it is a polarizer conventionally used in the production of a polarizing plate. Polarizers are prepared by dyeing a polyvinyl alcohol film with iodine or a dichroic dye and stretching it in a certain direction. Specifically, it is produced through a swelling process, a dyeing step, a stretching step and a crosslinking step. Methods of performing each step are commonly known to those skilled in the art.

Although the thickness of a polarizer is not specifically limited, Preferably it may be 20 micrometers-40 micrometers.

In the polarizing plate of the present invention, the protective film may be a surface treated protective film.

An optical display device which is another aspect of the present invention may include the polarizing plate. The optical display device may include an organic light emitting diode display device, but is not limited thereto.

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. 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.

Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

Specific specifications of the components used in the following examples and comparative examples are as follows.

(1) polyvinyl alcohol films (Kuraray, thickness 75㎛) as the material of the polarizer

(2) Triacetyl cellulose (TAC) film (Toppan, thickness 80㎛) as protective film

(3) Retardation film to cyclic olefin polymer λ / 4 film (Zeon, thickness 50㎛)

(4) acrylic adhesive resin with adhesive resin

(5) Benzotriazole-based absorbent as UV absorber (BASF, absorption wavelength = 300nm ~ 430nm)

(6) Triacetyl cellulose resins as resins for forming protective films

(7) UV absorbing layer Triacetyl cellulose type resin was used as resin for film formation.

Example  One

Polarizers were prepared by subjecting the material of the polarizer to a process such as dyeing and drawing. Specifically, after washing the polyvinyl alcohol film, iodine was adsorbed and stretched five times in an aqueous solution of boric acid at 50 ° C. to prepare a polarizer.

The retardation film was adhere | attached on one surface of the polarizer so that the retardation delay axis and the polarizing plate absorption axis might be 45 degrees. On the other side of the polarizer, a low reflective protective film was bonded using an adhesive. 100 parts by weight of the acrylic adhesive resin and 5 parts by weight of a UV absorber were mixed to prepare a solution for forming an adhesive layer, and then coated on one surface of a phase difference film to prepare a polarizing plate.

Example  2

Except for using 10 parts by weight of the UV absorber in Example 1 was carried out the same method to prepare a polarizing plate.

Example  3

A polarizer was prepared in the same manner as in Example 1. The retardation film was adhere | attached on one surface of the polarizer using an adhesive agent.

100 parts by weight of the protective film-forming resin and 5 parts by weight of a UV absorber were mixed to prepare a solution for film formation. After coating on a release film and drying, a protective film is prepared. The prepared protective film was bonded to the other side of the polarizer using an adhesive to prepare a polarizing plate.

Example  4

A polarizer was prepared in the same manner as in Example 1. The retardation film was adhere | attached on one surface of the polarizer using an adhesive agent. The protective film was bonded to the other side of the polarizer using an adhesive.

100 parts by weight of the film-forming resin and 5 parts by weight of the UV absorber were mixed to prepare a solution for forming a UV absorbing layer. After coating over the release film and drying, a UV absorbing layer is prepared. The prepared UV absorbing layer was adhered to one surface of the protective film to prepare a polarizing plate.

Comparative example  One

Except for using a UV absorber in the adhesive layer in Example 1 and having a lambda / 4 film having a wavelength dispersion characteristic, the same method was carried out to prepare a polarizing plate.

Experimental Example : Measurement of physical properties of polarizer

Using the polarizing plate prepared in Examples and Comparative Examples and the organic light emitting diode using the same, and evaluated the following physical properties, the results are shown in Table 1 and Figures 5 and 6 below.

(1) Transmittance: Using the Murakami Color Research Institute DOT-41 film and a halogen lamp, the transmittance of one polarizing plate at 380 nm to 780 nm at 1 nm intervals is measured, and the average value of the transmittance is calculated therefrom.

(2) Reflectance and color: The reflectance was measured at 5 nm intervals from 300 nm to 780 nm at an 8 degree reflectance using Konica Minolta CM-3600d, from which the average value of reflectance was calculated, and the color values x and y were calculated therefrom.

(3) Luminance: Blue luminance was measured using CS-1000A (Minolta Co., Ltd.) one hour after mounting on a 14 "AMOLED panel and having a constant panel temperature.

In addition, using the blue brightness measured from Comparative Example 1, the amount of brightness increase and decrease was calculated according to the following formula (1).

<Formula 1>

Luminance Increase (%) = (A-B) / B x 100

(A is the blue luminance measurement value, B is the blue luminance measurement value of Comparative Example 1)

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Transmittance (%) 42.871 42.620 42.979 43.012 42.363 reflectivity(%) 1.743 1.761 1.741 1.738 1.734 color x 0.252 0.251 0.253 0.252 0.218 y 0.225 0.237 0.226 0.224 0.168 blue luminance (Cd / m2) 206.2 206.7 207.1 207.3 206.5 Luminance increase / decrease (%) -0.15 0.10 0.29 0.39 -

As shown in Table 1, the polarizing plate of the present invention increased the reflectance color values x and y while minimizing the increase and decrease of the blue luminance.

Claims (16)

A polarizer; A protective film laminated on one surface of the polarizer; And an adhesive layer laminated on the other side of the polarizer,
The adhesive layer is a polarizing plate for an organic light emitting device comprising a UV absorber. A polarizer; An adhesive layer laminated on one surface of the polarizer; And at least one of a protective film and a UV absorbing layer laminated on the other surface of the polarizer,
The protective film and the UV absorbing layer is a polarizing plate for an organic light emitting device comprising a UV absorber having an absorption wavelength of 450nm or less. The polarizing plate for organic light emitting elements according to claim 1 or 2, wherein a phase difference film is further laminated between the polarizer and the adhesive layer. The polarizing plate of claim 1 or 2, wherein a functional film is further laminated on one surface of the protective film. The polarizing plate of claim 4, wherein the functional film comprises at least one selected from the group consisting of an antireflection layer, an antiglare layer, an antiglare and antireflection composite layer, and a hard coating layer. The polarizing plate of claim 1, wherein the adhesive layer comprises the UV absorber and the adhesive resin. The polarizing plate of claim 6, wherein the UV absorber is included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the adhesive resin. The method of claim 6, wherein the adhesive resin is (meth) acrylic, urethane, polyisobutylene, styrene-butadiene rubber (SBR), rubber, polyvinyl ether, epoxy, melamine crab, polyester, phenol , Silicon-based and mixtures thereof. The polarizing plate of claim 1, wherein the UV absorber has an absorption wavelength of 450 nm or less. The polarizing plate of claim 2, wherein the UV absorber is included in the protective film and is included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the protective film-forming resin. The polarizing plate of claim 2, wherein the UV absorbing layer comprises the UV absorber and a resin for forming a film. 12. The polarizing plate of claim 11, wherein the UV absorber is included in an amount of 0.1-20 parts by weight based on 100 parts by weight of the film forming resin. The method of claim 11, wherein the resin for film formation is cellulose, polyester, cyclic polyolefin, polycarbonate, polyether sulfone, polysulfone, polyamide, polyimide, polyolefin, polyarylene And polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, and a mixture thereof. The polarizer of claim 1 or 2, wherein the UV absorber is selected from the group consisting of benzotriazole-based, benzophenone-based, triazine-based, benzimidazole-based, and mixtures thereof. According to claim 1 or 2, wherein the protective film is cellulose, polyester, cyclic polyolefin, polycarbonate, polyether sulfone, polysulfone, polyamide, polyimide, polyolefin, A polyarylate-based, polyvinyl alcohol-based, polyvinyl chloride-based, polyvinylidene chloride-based, and a mixture thereof. An organic light emitting display device comprising the polarizing plate for organic light emitting device of claim 1.

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