KR20160047899A

KR20160047899A - Display panel and image display device having the same

Info

Publication number: KR20160047899A
Application number: KR1020140144418A
Authority: KR
Inventors: 김준석; 김인기; 김봉춘
Original assignee: 동우 화인켐 주식회사
Priority date: 2014-10-23
Filing date: 2014-10-23
Publication date: 2016-05-03

Abstract

The present invention relates to a display panel and, more specifically, to a display panel which has an upper polarizing plate, a liquid crystal panel, and a lower polarizing plate sequentially laminated, wherein the upper polarizing plate and the lower polarizing plate satisfy mathematical equation 1 to enable the liquid crystal panel to be in a cup shape under a heat-resistant condition, thereby minimizing a gap between the liquid crystal panel and a BLU and significantly reducing light leakage, ununiform black brightness, and Newton-ring phenomenon, and to an image display device with the same.

Description

DISPLAY PANEL AND IMAGE DISPLAY DEVICE HAVING THE SAME [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display panel and an image display apparatus having the same, and more particularly, to a display panel with minimized warping of a liquid crystal panel.

The display panel typically comprises a polarizing plate on each of upper and lower portions of a liquid crystal panel, and the polarizing plate is composed of a polarizing film layer on which a polarizing film is formed, and a protective layer for protecting the polarizing film layer and an adhesive layer for adhering, Is contacted with the liquid crystal panel, and then a certain pressure is applied to the polarizing plate to adhere to the liquid crystal panel through the adhesive layer to complete the liquid crystal panel. At this time, the polarizer attached to the outer surface of the liquid crystal panel may be attached with the same characteristics, or a polarizer having different characteristics may be attached to the outer surface of the liquid crystal panel according to the characteristics of the liquid crystal display device. In a liquid crystal display device having a wide viewing angle characteristic, a polarizing plate having a compensation film for a wide viewing angle internally is attached to an upper portion of a liquid crystal panel, and a general polarizing plate is attached to a lower portion. At this time, the direction of the polarizing film, the strength of the adhesive layer, the degree of stretching in forming the polarizing film, the number of stacked layers, and the like depend on the characteristics of the polarizing plate.

Therefore, when the polarizing plate having different properties is attached to the outer surface of the liquid crystal panel by a certain pressure as described above, the polarizing film layer formed by the stretching in the polarizing layer and the adhesive layer, And a defective screen such as a black luminance unevenness occurs due to warping of the liquid crystal panel.

In order to solve the above problems, Korean Patent No. 10-0978951 discloses a technique of preventing the liquid crystal panel from being warped by adjusting the size of the upper and lower polarizer plates or the intensity of the tackiness so that the upper and lower polarizer plates have the same contracting force Lt; / RTI > However, even if the contracting forces of the upper and lower polarizers are the same, the shrinkage behavior under the heat-resistant condition is different from that at room temperature, and the balancing aspect between the stretching direction and the unstretched direction must be taken into account. .

Korean Patent No. 10-0978951

An object of the present invention is to provide a display panel in which a light leakage phenomenon due to a difference in structure from a back light unit (BLU) as a light source is minimized by making a liquid crystal panel form a Cup type under a heat-resistant condition.

Another object of the present invention is to provide an image display apparatus which is capable of providing a high-quality image by providing the display panel and having excellent durability.

1. A display panel comprising: an upper polarizer plate, a liquid crystal panel, and a lower polarizer plate laminated in this order, wherein the upper polarizer plate and the lower polarizer plate satisfy the following formula (1)

[Equation 1]

10? Bp / Bv? 20

(Wherein Bp is F-MD / R-TD, Bv is F-TD / R-MD,

F-MD is the MD shrinkage of the upper polarizer,

F-TD is the shrinkage ratio in the TD direction of the upper polarizer,

R-MD is the shrinkage ratio in the MD direction of the lower polarizer plate,

R-TD is the shrinkage ratio in the TD direction of the lower polarizer plate).

2. The display panel of claim 1, wherein Bp in the formula (1) satisfies the following formula (2): < EMI ID =

&Quot; (2) "

5? Bp? 25.

3. The display panel of claim 1, wherein Bv in the equation (1) satisfies the following formula (3): < EMI ID =

&Quot; (3) "

0.5? Bv? 1.5.

4. The display panel of 1 above, wherein the upper polarizer comprises a polarizer having a thickness of 10 to 25 占 퐉.

5. The display panel of 1 above, wherein the lower polarizer plate comprises a polarizer having a thickness of 5 to 15 占 퐉.

6. The display panel of 1 above, wherein the upper polarizer comprises a polarizer having an MD shrinkage force of 1.5 to 2.5 N / mm.

7. The display panel of 1 above, wherein the lower polarizer plate comprises a polarizer having an MD shrinkage force of 0 to 1.5 N / mm.

8. The display panel of 1 above, wherein the upper polarizer plate comprises a polarizer having a TD shrinkage force of 0 to 0.5 N / mm.

9. The display panel of 1 above, wherein the lower polarizer plate comprises a polarizer having a TD shrinkage force of 0 to 0.5 N / mm.

10. The liquid crystal display panel of claim 1, wherein the liquid crystal panel comprises: an array substrate on which a thin film transistor and a pixel electrode are formed; a color filter substrate on which a color filter and a common electrode are formed; and a color filter substrate interposed between the pixel electrode of the array substrate and a common electrode And a liquid crystal.

11. An image display apparatus comprising a display panel according to any one of the above 1 to 10.

The display panel according to the present invention allows the liquid crystal panel to have a cup shape under heat-resistant conditions, thereby significantly reducing the occurrence of light leakage, black luminance unevenness, and Newton-Ring phenomenon due to a difference in structure from a backlight unit (BLU) have.

Further, the image display apparatus of the present invention can provide a high-quality image by providing the display panel, and has excellent durability.

Fig. 1 shows a warp shape under a heat-resistant condition of the display panel.
Fig. 2 shows a photographed image of light leakage evaluation under the heat-resistant condition of the display panel of the embodiment and the comparative example.

More specifically, the upper polarizer, the liquid crystal panel and the lower polarizer are stacked in order, and the upper polarizer and the lower polarizer satisfy the formula (1) And a display panel having the same, and capable of minimizing the gap between the liquid crystal panel and the BLU and simultaneously significantly reducing occurrence of light leakage, black luminance unevenness, and Newton-Ring phenomenon, and an image display device having the same.

Hereinafter, the present invention will be described in more detail.

The liquid crystal display panel typically has a polarizing plate on each of upper and lower portions of a liquid crystal panel. The polarizing plate has a polarizing direction which depends on the polarizing direction of the attached polarizing film, the strength of the adhesive layer, the degree of stretching in forming a polarizing film, The characteristics are different. When such a polarizing plate is attached to the outer surface of the liquid crystal panel by an external pressure, warping of the liquid crystal panel may occur due to the above-mentioned factors, and there is a problem that a screen defect such as black luminance unevenness occurs.

Accordingly, the present invention minimizes the warpage of the liquid crystal panel by stacking the polarizing plate satisfying the specific parameters for the shrinkage rate change on the upper and lower sides of the liquid crystal panel, and at the same time, It is considered that the light leakage phenomenon due to the difference in structure with the light source (BLU) can be effectively suppressed.

[Equation 1]

10? Bp / Bv? 20

Wherein Bp is F-MD / R-TD and Bv is F-TD / R-MD. Here, F-MD is the shrinkage ratio of the upper polarizer in the MD direction, F-TD is the shrinkage ratio of the upper polarizer in the TD direction, R-MD is the shrinkage ratio in the MD direction of the lower polarizer, and R-TD is the shrinkage ratio in the TD direction of the lower polarizer.

In the present invention, the term " Front " means the viewing side of the display with respect to the liquid crystal panel, and " Rear " means the other side of the viewer side.

In the present invention, the term "shrinkage ratio" means a rate of dimensional change measured in a state in which the polarizing plate is not adhered to another substrate. When the shrinkage ratio of the upper polarizer and the lower polarizer is measured under the same conditions, the measurement conditions are not particularly limited. However, since the display panel is warped under a high temperature condition, measurement at a temperature of 60 to 100 deg. C, more preferably 70 to 85 deg. C may be preferable for prevention and prediction of bending of the display panel.

In the present invention, the term "shrinkage force" refers to a value obtained by converting the magnitude of the force of shrinkage by the polarizer into a unit width. When the shrinkage ratio of the upper polarizer and the lower polarizer is measured under the same conditions, the measurement conditions are not particularly limited. The display panel is warped under a high temperature condition. Therefore, measurement at a temperature of 60 to 100 캜, more preferably 70 to 85 캜, may be preferable for prevention and prediction of bending of the display panel.

The value of Equation (1) is a parameter for the change in shrinkage ratio in the MD and TD directions of the upper polarizer and the lower polarizer of the liquid crystal panel. The thickness of the polarizer, the stretching direction of the polarizer, the elongation and contraction force, The number of layers formed, and the like.

When the value of Equation (1) is less than 10 or more than 20, the warping shape is deformed into the shape of a saddle or Cap, so that the gap between the BLU and the panel becomes large even if the deflection amount of the panel is small, .

The formula (1) may preferably be 12 or more and 17 or less. In this case, it is judged that the cup type is realized while the absolute deflection is small and the light leakage phenomenon can be minimized.

In the above formula (1), Bp is preferably 5 or more and 25 or less, and Bv is preferably 0.5 or more and 1.5 or less. When the above range is satisfied, warping of the liquid crystal panel can be minimized, and at the same time, So that the light leakage phenomenon can be minimized.

According to another embodiment of the present invention, the upper polarizer may have a polarizer having a thickness of 10 to 25 mu m, and preferably the thickness of the polarizer may be 12 to 23 mu m. Further, the lower polarizer plate may have a polarizer having a thickness of 5 to 15 mu m, and preferably the thickness of the polarizer may be 7 to 12 mu m. When each of the polarizers satisfies the above range, it is easy to realize thinning and can exhibit better physical properties under heat-resistant conditions.

In addition, the upper and lower polarizers may include a protective film on at least one surface. In the case of a protective film, a non-oriented film is usually used, and each of the upper and lower polarizers is formed in a single layer, and it is judged that the protective film does not greatly affect the above-mentioned parameters.

Accordingly, the thickness of the protective film is not particularly limited, but may be, for example, 10 to 200 mu m, preferably 10 to 150 mu m.

Further, a hard coating layer may be further formed on the other surface of the surface of the upper polarizer on which the liquid crystal panel is laminated.

According to another embodiment of the present invention, the upper polarizer may include a polarizer having a shrinking force in the MD direction of 1.5 to 2.5 N / mm, and the lower polarizer may include a polarizer having a shrinking force in the MD direction of 0 to 1.5 N / mm Lt; / RTI > When the shrinking force in the MD direction satisfies the above range, the absolute deflection can be minimized, and it is easy to prevent breakage and curl adjustment during the process.

According to another embodiment of the present invention, the upper polarizer may include a polarizer having a shrinking force in the TD direction of 0 to 0.5 N / mm, and the lower polarizer may include a polarizer having a shrinking force in the TD direction of 0 to 0.5 N / mm . When the shrinkage force in the TD direction satisfies the above range, the shrinkage force balance with the upper polarizer can be optimized, and durability and film lamination property can be improved because the dimensional change is small.

Hereinafter, the constituent elements of the polarizing plate used in the present invention will be described in more detail.

The polarizer of the present invention uses iodine as a dichroic dye in which a dichroic dye is adsorbed and oriented on a stretched polyvinyl alcohol resin film.

The polyvinyl alcohol-based resin constituting the polarizer can be obtained by saponifying a polyvinyl acetate-based resin. Examples of the polyvinyl acetate resin include polyvinyl acetate, which is a homopolymer of vinyl acetate, and copolymers of vinyl acetate and other monomers copolymerizable therewith. Other monomers copolymerizable with vinyl acetate include acrylamide monomers having an unsaturated carboxylic acid type, an unsaturated sulfonic acid type, an olefin type, a vinyl ether type, and an ammonium group. The polyvinyl alcohol resin may also be modified. For example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The saponification degree of the polyvinyl alcohol-based resin is usually 85 to 100 mol%, preferably 98 mol% or more. The polymerization degree of the polyvinyl alcohol-based resin is usually 1,000 to 10,000, preferably 1,500 to 5,000.

Such a polyvinyl alcohol-based resin film is used as the original film of the polarizer. The method of forming the film of the polyvinyl alcohol-based resin is not particularly limited, and a known method can be used. The thickness of the original film is not particularly limited, and may be, for example, 10 to 150 mu m.

The polarizer of the present invention is produced by continuously uniaxially stretching a polyvinyl alcohol-based film in an aqueous solution, staining with a dichroic dye and adsorbing, treating with an aqueous solution of boric acid, and washing and drying.

The uniaxial stretching of the polyvinyl alcohol film may be performed before dyeing, concurrently with dyeing, or may be performed after dyeing. If uniaxial stretching is carried out after dyeing, it may be carried out before the boric acid treatment, or may be carried out during the boric acid treatment. Of course, it is also possible to perform uniaxial stretching in a plurality of such steps. For uniaxial stretching, other rolls or rolls of different circumferences may be used. The uniaxial stretching may be either dry stretching in the air or wet stretching in the state of being swollen with a solvent. The stretching ratio is usually 4 to 8 times.

As a step of dyeing a stretched polyvinyl alcohol film with a dichroic dye, for example, a method of immersing a polyvinyl alcohol film in an aqueous solution containing a dichroic dye can be used. Iodine is used as the dichroic dye. It is preferable that the polyvinyl alcohol film is pre-immersed in water before dyeing to swell.

In the dyeing step, a method of dying and dyeing a polyvinyl alcohol-based film into an aqueous solution for dyeing usually containing iodine and potassium iodide can be used. Usually, the content of iodine in an aqueous solution for dyeing is 0.01 to 1 part by weight with respect to 100 parts by weight of water (distilled water), and the content of potassium iodide is 0.5 to 20 parts by weight with respect to 100 parts by weight of water. The temperature of the aqueous solution for dyeing is usually 20 to 40 占 폚, and the immersion time (dyeing time) is usually 20 to 1,800 seconds.

The step of treating the dyed polyvinyl alcohol film with boric acid can be carried out by immersing it in an aqueous solution containing boric acid. The content of boric acid in an aqueous solution containing boric acid is usually 2 to 15 parts by weight, preferably 5 to 12 parts by weight based on 100 parts by weight of water. Since iodine is used as the dichroic dye, it is preferable that the aqueous solution containing boric acid contains potassium iodide. The content thereof is usually 0.1 to 15 parts by weight, preferably 5 to 12 parts by weight, based on 100 parts by weight of water. The temperature of the boric acid-containing aqueous solution is usually 50 ° C. or higher, preferably 50 to 85 ° C., and more preferably 60 to 80 ° C. The immersing time is usually 60 to 1,200 seconds, preferably 150 to 600 seconds, Preferably 200 to 400 seconds.

After the boric acid treatment, the polyvinyl alcohol film is usually washed with water and dried. The washing treatment can be carried out by immersing the boric acid-treated polyvinyl alcohol-based film in water. The water temperature of the water treatment is usually 5 to 40 占 폚, and the immersion time is usually 1 to 120 seconds. After washing with water, the polarizer can be obtained. The drying treatment can be usually carried out using a hot air dryer or a far infrared ray heater. The drying treatment temperature is usually 30 to 100 占 폚, preferably 50 to 80 占 폚, and the drying time is usually 60 to 600 seconds, preferably 120 to 600 seconds.

The protective film of the present invention is laminated on at least one side of the polarizer, and the kind of the protective film is not particularly limited as long as it is excellent in transparency, mechanical strength, thermal stability, moisture shielding property, isotropy and the like. Examples thereof include polyethylene terephthalate, polyethylene isophthalate , And polybutylene terephthalate; Cellulose-based films such as diacetylcellulose and triacetylcellulose; Polycarbonate film; Acrylic films such as polymethyl (meth) acrylate and polyethyl (meth) acrylate; Styrene-based films such as polystyrene and acrylonitrile-styrene copolymer; Polyolefin-based films such as polyethylene, polypropylene, cyclo-based or norbornene-structured polyolefin, and ethylene propylene copolymer; Polyimide-based films; Polyethersulfone-based films; A sulphone film, or the like can be used, but the present invention is not limited thereto.

If necessary, a surface treatment layer such as a hard coating layer, an antireflection layer, and an antiglare layer may be further laminated on the protective film. Specifically, the hard coat layer serves to prevent the surface of the polarizing plate from being damaged, and may be formed of, for example, an acrylic or silicone resin having excellent adhesiveness and hardness. The antireflection layer is for preventing reflection of external light on the surface of the polarizing plate, and may be formed by a known method. In addition, the antiglare layer is for preventing the visibility that occurs when external light is reflected on the surface of the polarizing plate. For example, the antiglare layer may be formed by a roughening method such as a sandblast method or an embossing method, or by mixing transparent ultrafine particles A method in which a composition is applied and cured, or the like.

In the present invention, the adhesion treatment between the polarizer and the protective film may be performed by an adhesive layer formed of an adhesive composition. The adhesive composition used in the present invention is not particularly limited, but isocyanate, polyvinyl alcohol, gelatin, A vinyl polymer latex type, and a water-soluble polyester-based adhesive composition.

It is preferable that the adhesive composition is in a liquid form in order to form a uniform adhesive layer on the surface of a polarizer or a protective film which is an adherend. A solution type or a dispersed liquid type of various solvents can be used for such a liquid type adhesive, and a solution type is preferable in view of the coated surface of the substrate, and a solution type or a dispersed liquid type in which water is used as a solvent is suitable from the viewpoint of stability.

For the purpose of shortening the drying process, a water / alcohol mixed solvent in which an alcoholic solvent having a boiling point lower than that of water is easily mixed with water in an adhesive solution may be used. The boiling point of the alcoholic solvent is preferably 100 占 폚 or lower, particularly 80 占 폚 or lower, or 70 占 폚 or lower.

The thickness to which the adhesive composition is applied (before drying) is usually about 0.01 to 10 mu m, preferably 0.05 to 5 mu m, and most preferably 0.1 to 1 mu m. The thickness of the adhesive layer after drying is usually 0.001 to 5 mu m, preferably 0.01 to 2 mu m, more preferably 0.01 to 1 mu m or less. If the thickness of the adhesive layer exceeds 5 탆, the problem of appearance defects of the polarizing plate tends to occur.

A liquid crystal panel according to the present invention includes an array substrate on which a thin film transistor and a pixel electrode are formed, a color filter substrate on which a color filter and a common electrode are formed, and a liquid crystal interposed between the pixel electrode of the array substrate and a common electrode of the color filler substrate And the components of the liquid crystal panel and the manufacturing method thereof can be used without limitation as long as they do not depart from the object of the present invention.

The present invention relates to an image display apparatus having the display panel. The image display apparatus of the present invention may further include configurations known in the art in addition to the above configuration.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to be illustrative of the invention and are not intended to limit the scope of the claims. It will be apparent to those skilled in the art that such variations and modifications are within the scope of the appended claims.

Example And Comparative Example

&Lt; Production of Polarizer >

A polyvinyl alcohol resin film having an average degree of polymerization of about 2,400 and a degree of saponification of 99.9 mol% or more and having a thickness of 75 탆 was immersed in pure water at 30 캜 for 2 minutes and stretched to about 1.5 times. Thereafter, the film was dipped in a dyeing solution at 30 DEG C containing iodine / potassium iodide / water in a weight ratio of 0.01 / 1.0 / 100 for 3 minutes, and stretched to about 2.0 times. Thereafter, the resultant was immersed in an aqueous solution of potassium iodide / boric acid / water mixed at a weight ratio of 10/5/100 at 53 ° C for 1 minute, and stretched to about 2.0 times. Thereafter, the film was washed with pure water at 15 DEG C for 1.5 seconds and then dried at 50 DEG C for 5 minutes to prepare a polarizer in which iodine was adsorbed and oriented on polyvinyl alcohol. At this time, the respective stretching magnifications and the like were adjusted to prepare a polarizer having a shrinking force and a thickness that were the same as those shown in Table 1 below.

&Lt; Production of polarizing plate &

A saponified TAC film and a COP film having a thickness of 20 to 40 占 퐉 were bonded to both surfaces of the polarizer using the adhesive composition. The adhesive composition was prepared by mixing water with 3 parts by weight / 100 parts by weight of a modified polyvinyl alcohol (Kosepaima Z200, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), 10% aqueous sodium glycidylate solution (SPM- The polarizing plate was coated on both sides of the polarizing film, and the TAC film and the COP film were bonded to each other. The polarizing plate was then dried for 3 to 5 minutes at a maximum temperature of 75 ° C, Bottom).

division Top
Polarizer thickness (占 퐉) bottom
Polarizer thickness (占 퐉) Upper Polarizer Shrinkage Lower Polarizer Shrinkage Contraction ratio
Bp / Bv MD Shrinkage
(N / mm) TD Shrinkage
(N / mm) MD Shrinkage
(N / mm) Polarizer thickness
(탆) Polarizer thickness
(탆) MD Shrinkage
(N / mm) Example 1 23 12 2.2 0.45 1.2 0.38 10.68 0.95 11.24 Example 2 23 7 2.1 0.45 0.5 0.17 22.88 1.31 17.65 Example 3 12 7 1.6 0.24 0.5 0.17 13 0.94 13.88 Comparative Example 1 28 28 5.8 1.1 5.8 1.1 2.56 0.37 6.88 Comparative Example 2 28 23 5.8 1.1 2.1 0.45 1.7 0.38 4.55 Comparative Example 3 28 12 5.8 1.1 1.2 0.38 23.9 0.88 27.1 Comparative Example 4 28 7 5.8 1.1 0.5 0.17 58.27 1.22 48.88 Comparative Example 5 23 28 2.2 0.45 5.8 1.1 0.97 0.34 2.87 Comparative Example 6 23 23 2.1 0.45 2.1 0.45 0.77 0.4 1.94 Comparative Example 7 12 28 1.6 0.24 5.8 1.1 0.67 0.26 2.59 Comparative Example 8 12 17 2.1 0.24 1.7 0.33 6.66 0.73 9.15 Comparative Example 9 12 23 2.2 0.24 2.1 0.45 0.46 0.31 1.49 Comparative Example 10 7 7 0.5 0.17 0.5 0.17 8.29 0.2 41.53 Comparative Example 11 7 12 0.6 0.17 1.2 0.38 4.07 0.16 25.62 Comparative Example 12 7 23 0.5 0.17 2.1 0.45 0.33 0.06 5.2 Comparative Example 13 7 28 0.4 0.17 5.8 1.1 0.34 0.07 5.26

In Table 1, the shrinking force of the polarizer was measured using TMA of TA instrument. When a polarizer having a width of 2 mm and a length of 40 mm was heated at 80 캜, 240 minutes after the start of heating, the polarizer was shrunk in the MD or TD direction Is the value obtained by converting the magnitude of the force to the unit width. A polarizer having a width of 2 mm was sandwiched between two chucks, one of which was fixed and the other was equipped with a force gauge, so that the distance between the chucks was 40 mm (measurement direction). When the substrate was continuously heated at 80 DEG C for 240 minutes, The gauges were measured (the average value was measured 5 times).

In Table 1, the shrinkage ratios in the MD and TD directions of the polarizing plate were measured by cutting the polarizing plate to a size of 100 X 100 mm, measuring the size after initial treatment (room temperature: 15 to 25 ° C) and heat treatment at 85 ° C for 100 hours, And the rate of change in size in the TD direction were measured (total of 5 measurements, 3 points per measurement were measured to derive an average value).

Experimental Method

The upper polarizer plate and the lower polarizer plate were cut to a size of 255 mm x 144 mm (10.1 ", and then bonded to both sides of a liquid crystal panel (SDC, LTN101AL03) having a size of 255 mm x 144 mm (10.1 &

(1) Flexural evaluation of liquid crystal panels

The prepared display panel was placed in an oven at 85 ° C for 100 hours using a two-dimensional measuring machine of INTEK IMS, left for 2 hours at room temperature, and then the maximum value of the flexure of the liquid crystal panel was measured (obtained by measuring the average value five times) The results are shown in Table 2. And also shows a warp shape (saddle type, Cap type, Cup type) (see Fig. 1).

It is preferable to have a cup-type structure in a heat-resistant condition, and at the same time, it is preferable that the bending amount has a value of less than 2 mm.

Under the same heat-resistant conditions, the shape of the backlight unit (BLU), which is a light source, is a cup shape. When the bending shape of the liquid crystal panel is different from the bending shape of the light source (BLU), a light leakage phenomenon occurs due to the bending. Therefore, when the liquid crystal panel deviates from the cup shape under heat-resistant conditions,

division Deflection (mm) Bend shape Example 1 1.13 Cup type Example 2 1.77 Cup type Example 3 0.68 Cup type Comparative Example 1 2.20 Cap type Comparative Example 2 1.90 Saddle type Comparative Example 3 3.11 Saddle type Comparative Example 4 2.35 Saddle type Comparative Example 5 1.11 Saddle type Comparative Example 6 1.65 Cap type Comparative Example 7 2.71 Saddle type Comparative Example 8 1.18 Cap type Comparative Example 9 1.44 Saddle type Comparative Example 10 0.90 Cap type Comparative Example 11 1.07 Saddle type Comparative Example 12 1.86 Saddle type Comparative Example 13 2.23 Saddle type

(2) Light beam evaluation

After the evaluation of the bending of the liquid crystal panel in the heat-resistant condition, the vertical direction of the panel was photographed with a camera to evaluate whether the light leakage occurred in the upper, lower, left, and right 4-coner.

Referring to Table 2 and FIG. 2, when the parameters of Equation 1 according to the present invention were satisfied, it was confirmed that the warpage was less than 2 mm, and at the same time, it was Cup-shaped and no light leakage occurred.

However, in the case of a display panel deviating from the scope of the present invention, even when the warping amount exceeds 2 mm or the warping amount is within 2 mm, the warp shape is saddle type or Cap type and the gap with the BLU is large, ) Was observed.

Claims

A liquid crystal panel and a lower polarizer are laminated in this order, and the upper polarizer and the lower polarizer satisfy the following expression (1)
[Equation 1]
10? Bp / Bv? 20
(Wherein Bp is F-MD / R-TD, Bv is F-TD / R-MD,
F-MD is the MD shrinkage of the upper polarizer,
F-TD is the shrinkage ratio in the TD direction of the upper polarizer,
R-MD is the shrinkage ratio in the MD direction of the lower polarizer plate,
R-TD is the shrinkage ratio in the TD direction of the lower polarizer plate).

2. The display panel according to claim 1, wherein Bp in the equation (1) satisfies the following expression (2)
&Quot; (2) "
5? Bp? 25.

The display panel according to claim 1, wherein Bv in the equation (1) satisfies the following formula (3)
&Quot; (3) "
0.5? Bv? 1.5.

The display panel according to claim 1, wherein the upper polarizer comprises a polarizer having a thickness of 10 to 25 占 퐉.

The display panel according to claim 1, wherein the lower polarizer plate comprises a polarizer having a thickness of 5 to 15 占 퐉.

The display panel according to claim 1, wherein the upper polarizer comprises a polarizer having an MD retraction force of 1.5 to 2.5 N / mm.

The display panel according to claim 1, wherein the lower polarizer plate comprises a polarizer having a MD shrinkage force of 0 to 1.5 N / mm.

The display panel according to claim 1, wherein the upper polarizer comprises a polarizer having a TD shrinkage of 0 to 0.5 N / mm.

The display panel according to claim 1, wherein the lower polarizer plate comprises a polarizer having a TD shrinkage of 0 to 0.5 N / mm.

The liquid crystal display according to claim 1, wherein the liquid crystal panel comprises: an array substrate on which a thin film transistor and a pixel electrode are formed; a color filter substrate on which a color filter and a common electrode are formed; and a liquid crystal interposed between the pixel electrode of the array substrate and a common electrode of the color filler substrate The display panel.

An image display apparatus comprising the display panel according to any one of claims 1 to 10.