KR20070096905A - Liquid crystal display and glare-proof polarizing film laminate used therein - Google Patents

Abstract

An LCD and a glare-proof polarizing film lamination structure used in the same are provided to realize an excellent glare-proof characteristic and a high contrast, thereby improving the visibility and the brightness of the LCD. An LCD comprises an LCD cell, a pair of linear polarizing elements(20) positioned on both surfaces of the LCD cell, a first retardation plate(26) interposed between a first substrate of the LCD cell and one of the linear polarizing elements, a second retardation plate(27) interposed between the first retardation plate and the first substrate or between a second substrate of the LCD cell and the other of the linear polarizing elements, and an anti-glare layer(30) positioned on one of the linear polarizing elements. The first retardation plate has a refractive index satisfying a relation of nx >ny >= nz. A retardation axis of the first retardation plate is positioned in parallel with or vertically to a transmission axis of a neighboring linear polarizing plate. The second retardation plate has a refractive index satisfying a relation of nx = ny >nz. The anti-glare layer has an entire reflective resolution of 50%, and a haze of less than 5% with respect to a vertically incident light. The entire reflective resolution is measured by using three optical frequency combs, which consist of dark lines and bright lines having 0.5mm, 1.0mm, and 2,0mm, respectively, and a profile of reflection rate for an incident light at an incident angle of 30 degrees. A surface of the anti-glare layer is composed of voronoi polygons having an average area of 50 to 1500 um^2.

Description

Liquid crystal display and anti-glare polarizing film stack used therein {LIQUID CRYSTAL DISPLAY AND GLARE-PROOF POLARIZING FILM LAMINATE USED THEREIN}

1A-1D are schematic cross-sectional views of four examples of a liquid crystal display according to the present invention.

2 is a schematic cross-sectional view of an example of an anti-glare polarizing film stack of the present invention.

3 is a schematic cross-sectional view of another example of an anti-glare polarizing film stack of the present invention.

4 is a schematic perspective view showing an incidence direction and a reflection direction of light with respect to the antiglare layer.

FIG. 5 is an example of a graph showing the reflectance of reflected light with respect to incident light at an angle of 30 degrees from the vertical line of the antiglare layer of FIG. 4 with respect to the reflection angle (vertical axis is expressed in logarithmic scale).

6 is a schematic perspective view illustrating an algorithm for determining the vertices of the convex portions of the antiglare;

FIG. 7 is a Voronoi diagram showing an example of Voronoi division using the vertices of convex portions of the glare membrane as a generatrix. FIG.

8a to 8e schematically illustrate the steps of a preferred method for producing an antiglare layer.

9 is a schematic cross-sectional view of an electroless nickel plated antiglare layer after polishing.

* Explanation of symbols for the main parts of the drawings

10: liquid crystal cell 20, 21: linear polarizer

17 liquid crystal layer 26 first delay plate

27: second delay plate 30: antiglare layer

The present invention relates to liquid crystal displays having improved antiglare properties and to antiglare polarizing film stacks useful in such liquid crystal displays.

Liquid crystal displays are increasingly used in portable TVs, notebook-sized personal computers, because they have good characteristics such as light weight, thinness, low power consumption, and the like. Recently, liquid crystal displays are also increasingly used in image viewing devices such as TVs with large screens and the like. In the case of liquid crystal displays used for displaying images like TV sets, visibility, in particular the contrast ratio when the screen is viewed from the front, and the contrast ratios when the screen is viewed in an oblique direction, That is, the viewing angle characteristic is important. Various driving modes of liquid crystal cells have been proposed to improve viewing angle characteristics.

As an example of a liquid crystal display with improved viewing angle characteristics, JP 2548979 B is a vertical arrangement in which rod-shaped liquid crystal molecules having positive (+) or (-) anisotropy of dielectric constant are arranged in a direction perpendicular to the substrate of the liquid crystal cell (VA). A mode liquid crystal display is disclosed. In the VA mode, since the liquid crystal molecules are arranged in a direction perpendicular to the substrate of the liquid crystal cell in the undriven state of the display, light can pass through the liquid crystal layer without changing the polarization. Thus, when a pair of linear polarizers are respectively located at the front and the back of the liquid crystal panel so that the polarization axes of the polarizers are perpendicular to each other, a substantially completely dark display is seen from the front and thus a high contrast ratio is obtained.

However, in a VA mode liquid crystal display comprising only linear polarizers positioned on a liquid crystal cell, when the screen of the display is viewed in an oblique direction, the angle formed by the polarization axes of the linear polarizers is off of 90 degrees and the rod-shaped liquid crystal molecules in the cell. They exhibit birefringence, so that light leaks and therefore the contrast ratio is greatly reduced.

In order to prevent light leakage in the VA mode liquid crystal display, an optical compensation film must be provided between the liquid crystal cell and the linear polarizer (s). For this purpose, biaxial retarder plates are inserted between the liquid crystal cell and the individual polarizers, or the uniaxial retarder and the complete biaxial retarder are located on the front and back of the liquid crystal cell, or both retarder plates. All of them are located on one surface of the liquid crystal cell. For example, JP-A-2001-109009 shows that a-plates (ie, (+) uniaxial retardation plates) and c-plates (ie, complete biaxial retardation plates) are placed between the liquid crystal cell and the front and rear polarizers, respectively. Disclosed is an inserted VA mode liquid crystal display.

A positive short axis delay plate means a retardation film having an R ₀ / R _th ratio of approximately 2, where R ₀ is an inplane delay value and R _th is a delay value in the thickness direction. A perfect biaxial retarder means a retardation film with an inplane value R ₀ of approximately zero. The inplane delay value R ₀ and the delay value R _th in the thickness direction are defined by the following formulas (1) and (2), respectively.

R ₀ = (n _x -n _y ) × d (1)

R _th = [(n _x + n _y ) / 2-n _z ] × d (2)

Where n _x Is the index of refraction in the in-plane phase retardation axis, n _y Is the index of refraction in the in-plane phase propagation axis direction, n _z Is the refractive index in the thickness direction, and d is the thickness of the film.

n_y) 따라서 R₀/R_th 는 대략 2 이다 (R₀/R_th

2). 단축 지연막을 가지면, 비율 R₀/R_th 은 막의 배향 조건에 따라서 대략 1.8 과 2.2 의 범위에서 변할 수도 있다. 완벽한 2 축 지연막의 경우에, n_x 은 거의 n_y 와 동일하며 (n_x

n_y), 따라서 R₀ 은 대략 0 이다 (R₀

0). 완벽한 2 축 막을 가지면, 오직 두께 방향으로의 굴절률은 다른 굴절률들과 다르기 (더 작기) 때문에, 이 지연막은 (-) 단축을 가지며 따라서 수직 선 방향으로 광학축을 가진 막, 즉, 상술한 바와 같이 c-판이라 불린다. 2 축 지연막에서, 굴절률들은 n_x > n_y > n_z 의 관계를 가진다.In the case of a positive short retardation film, n _z Is almost equal to n _y (n _z

n _y ) Thus R ₀ / R _th is approximately 2 (R ₀ / R _th

2). If you have a uniaxial delay membrane, the ratio R ₀ / R _th May vary in the range of approximately 1.8 and 2.2 depending on the orientation conditions of the film. In the case of a perfect biaxial retardation membrane, n _x Is almost equal to n _y (n _x

n _y ), so R ₀ is approximately 0 (R ₀

0). With a perfect biaxial film, since the refractive index only in the thickness direction is different (smaller) than the other refractive indices, this retardation film has a negative axis and thus has an optical axis in the vertical line direction, that is, c as described above. It's called a plate. In the biaxial retardation film, the refractive indices are n _x > n _y > n _z

The polarizing plate usually has a protective layer on at least one surface of the polarizing film. The protective layer typically comprises a triacetyl cellulose membrane. Various attempts have been made to replace the triacetyl cellulose film with another resin film or to impart a delay property to the protective layer. For example, JP-A-08-43812 discloses that one or more protective layers of a polarizing film consist of a birefringent film. JP-A-07-287123 discloses that a protective layer of a polarizing film is made of a norbornene film (cyclic olefin film).

In addition, image display devices such as liquid crystal displays largely lose visibility when the device's image display screen reflects external light. Thus, in applications where importance is placed on image quality and visibility, such as monitor screens of TVs and personal computers, the screen surface of display devices is usually processed to prevent reflection of external light. The antiglare treatment, which disperses the angle of incidence, thereby forming fine irregularities on the surface to smudge the reflected image, as a means to prevent reflection, is such a treatment is performed at a relatively low cost. It is preferably used in applications such as large size personal computers, monitors, TVs and the like.

As a film providing such anti-glare properties, JP-A-2002-365410 discloses an optical film having fine non-uniformities formed on the surface of the film, and the light profile reflected from the surface shows that the light surface is in the direction of -10 degrees from the vertical line. The specific relationship is satisfied when the light enters and only the reflected light from the surface is observed. JP-A-2002-189106 discloses an antiglare comprising a transparent resin film and an ionizing radiation curable resin layer having a fine nonuniformity, wherein the nonuniformity is adjacent convex portions at a data level for three-dimensional surface roughness. In order to form such fine non-uniformities in which the average distance and ten-point average roughness between them are individually within a specific range, an ionizing radiation curable resin is inserted between the embossing mold and the transparent resin film. It forms on the surface of a transparent resin film by hardening an ionization curable resin layer.

JP-A-2004-90187 discloses a method for producing a roll used in the manufacture of a film having fine nonuniformities on a surface, the method comprising forming a plated metal layer on the surface of an embossing roll, a plated metal layer Mirror polishing the surface of the substrate, blasting the mirror polished surface of the plated metal layer with ceramic beads, and selectively peening the plated metal layer.

Typically, it is necessary to use a high haze glare of at least 10% to prevent reflection of external light and to ensure sufficient visibility, and such high haze glare are used in notebook-sized personal computers, TVs. It is widely used for such purposes. However, at least 10% high haze glare has the drawback that the contrast measured in bright spaces is reduced due to the high reflection-scattering properties. In addition, it is also a drawback of the high haze antiglare that the antiglare also reduces the contrast measured in the darkroom, which the liquid crystal display essentially has.

To solve these problems, JP-A-2006-53371 discloses a glare having a low haze and a specific reflection profile, where the glare impinges fine particles to form non-uniforms on a polished metal plate, forming a mold. Electroless nickel plating on the nonuniform surface of the metal plate to reduce the depth of the nonuniformities, and by moving the surface nonuniformities of the mold to the surface of the transparent resin film. JP-A-2006-39270 is a VA mode liquid crystal display that applies an anti-glare layer of a surface where the visibility of the liquid crystal display is divided into specific area regions along with a linear polarizer, a uniaxial or biaxial retarder and a perfect biaxial retarder It demonstrates improvement by doing.

One object of the present invention is to provide a liquid crystal display, and in particular, to provide a VA mode liquid crystal display having improved viewing angle characteristics without increasing high antiglare characteristics and haze.

Another object of the present invention is to provide an anti-glare polarizing film stack suitable for such a liquid crystal display.

The present invention relates to a VA mode liquid crystal cell sandwiched between a pair of polarizers, and between a liquid crystal cell substrate and a polarizer plate coated with an antiglare having an improved reflectance profile disclosed in JP-A-2006-53371. It is based on the liquid crystal display of JP-A-2006-39270 that includes two types of retardation plates located in both spaces. Therefore, various studies have been conducted to further improve the anti-glare characteristics of liquid crystal displays. As a result, the provision of an antiglare layer with a particular surface shape on certain optical properties and on the display screen surface, i.e. the viewing surface, results in a VA mode liquid crystal cell, a pair of linear polarizers located on the front and back of the liquid crystal cell, A positive biaxial or biaxial retardation plate positioned between one cell substrate and one linear polarizer, and a perfect biaxial retardation plate positioned between one cell substrate and one linear polarizer or between another cell substrate and another linear polarizer. It is known to greatly improve the contrast of liquid crystal displays. In addition, new anti-glare polarizing film stacks useful for such liquid crystal displays have been known. Thus, the present invention was completed after other studies.

Accordingly, the present invention provides a liquid crystal cell comprising a liquid crystal layer and a pair of cell substrates sandwiched between cell substrates oriented in a direction substantially perpendicular to the substrate near the substrate where no liquid crystal molecules are applied;

A pair of linear polarizers located on the outer surface of the individual cell substrates sandwiching the liquid crystal cell in between;

A first retardation plate located between one of the cell substrates with individually a linear polarizer, the first retardation plate is n _x> n _y ≥ n has a refractive index that satisfies the relationship of _z, the phase retardation of the first retardation plate Wherein the axis is positioned such that it is substantially perpendicular to or substantially parallel to the transmission axis of the adjacent linear polarizer, wherein n _x and n _y are the major refractive indices in the film plane and n _z is the refractive index in the thickness direction of the film. plate;

n_y > n_z 의 관계를 만족시키는 굴절률들을 가지며, 여기에서, n_x, n_y 및 n_z 는 상기 정의한 것과 동일한, 상기 제 2 지연판; 및A second retardation plate positioned between the first retardation plate and the cell substrate or between another cell substrate and a linear polarizer opposite thereto, the second retardation plate being n _×

said second retardation plate having refractive indices satisfying a relationship of n _y > n _z , wherein n _x , n _y and n _z are the same as defined above; And

An antiglare layer located on the surface of one of the linear polarizers facing the liquid crystal cell, wherein the antiglare layer has a haze of 5% or less for normal incident light, and 0.5 mm, 1.0 mm and 2.0 mm, respectively. When measured at an angle of incidence of 45 degrees of light using three optical frequency combs consisting of dark and bright lines with a width of, the total reflection resolution is 50% or less and 2% or less for incident light entering an angle of incidence of 30 degrees Reflectance R (30) at a 30 degree reflection angle, reflectance R (40) at a reflection angle of 40 degrees less than or equal to 0.003% with respect to incident light entering a 30 degree incidence angle, and 60 for incident light entering R (≥60) at an angle of incidence 30 degrees even more reflectivity at a certain direction in the angle of reflection when having a ratio of R (≥60) of 0.001 or less for R (30), an antiglare layer on the surface is an average area of 50 ㎛ ² to 1,500 ㎛ ^2, bar Straight Advantageously, comprises of 300 ㎛ ² to 1000 ㎛ ² polygon, where the polygon comprises the anti-glare layer using the vertices of the convex parts of the surface non-uniform dyed generatrix formed by the Voronoi partition of the surface A liquid crystal display is provided.

In the liquid crystal display of the present invention, the laminate including the antiglare layer, the linear polarizer and the retardation plate has a new structure. Accordingly, the present invention also provides an antiglare polarizing film stack comprising an antiglare layer, a linear polarizer, and a retardation plate, laminated in order, wherein the antiglare layer has a haze of 5% or less with respect to the vertical incident light, and 0.5, respectively. When measured at an angle of incidence of 45 degrees of light using three optical frequency combs consisting of dark and bright lines with widths of mm, 1.0 mm and 2.0 mm, the total reflection resolution of 50% or less and incident light entering an angle of incidence of 30 degrees A reflectance R (30) at a reflection angle of 30 degrees of 2% or less with respect, a reflectance R (40) of a reflection angle of 40 degrees of 0.003% or less with respect to incident light entering a 30 degree of incidence angle, and R (≥60) at an incidence angle of 30 degrees It has a ratio of R (≥60) to R (30) that is 0.001 or less when the reflectance in any direction at a reflection angle of 60 degrees or more with respect to the incident incident light, and the surface of the antiglare layer is 50 µm ² to 1,500 An average area of μm ² , preferably from 300 μm ² to 1000 μm ² , wherein the polygons are formed by Voronoi division of the surface using the vertices of the convex portions of the surface non-uniformities as the parent point and ;

n_y > n_z 의 관계를 만족시키는 굴절률들을 가진 제 2 지연판으로 구성된 그룹으로부터 선택된 하나 이상의 지연판을 포함하며, 여기에서, 제 1 지연판이 사용될 때, 제 1 지연판의 위상 지연축이 선형 편광자의 투과축에 실질적으로 수직인 각도 또는 실질적으로 평행이 되도록 제 1 지연판이 위치된다는 조건하에서, n_x 및 n_y 는 막 평면에서 주 굴절률이며 n_z 가 막의 두께 방향으로의 굴절률이다.The delay plate is a first delay plate and n _x having refractive indices satisfying a relationship of n _x > n _y ≧ n _z .

and at least one retardation plate selected from the group consisting of second retardation plates having refractive indices satisfying a relationship of n _y > n _z , wherein when the first retardation plate is used, the phase retardation axis of the first retardation plate is linear Under the condition that the first retardation plate is positioned at an angle substantially perpendicular to or substantially parallel to the transmission axis of the polarizer, n _x and n _y are the main refractive indices in the film plane and n _z is the refractive index in the thickness direction of the film.

n_y ≥ n_z 의 관계를 가진 단일 제 2 지연판으로 구성될 수도 있다. 게다가, 지연판은 제 1 지연판 및 제 2 지연판의 적층으로 구성될 수도 있다. 이 경우에, 적층은 바람직하게는 제 1 지연판이 선형 편광자를 마주보고, 제 1 지연판의 위상 지연축이 선형 편광자의 투과축에 실질적으로 평행 또는 실질적으로 수직하도록 위치된다.In the antiglare layer stack of the present invention, the retardation plate may be composed of a single first retardation plate having a relationship of n _x > n _y ≧ n _z . In this case, the retardation plate is positioned such that the phase retardation axis of the retardation plate is substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer. Optionally, the delay plate is n _x

It may be composed of a single second delay plate having a relationship of n _y ≥ n _z . In addition, the retardation plate may consist of a stack of a first retardation plate and a second retardation plate. In this case, the stacking is preferably positioned such that the first retardation plate faces the linear polarizer and the phase retardation axis of the first retardation plate is substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer.

In the antiglare polarizing film stack of the present invention, the antiglare layer is preferably composed of a resin film having fine nonuniformities on the surface, wherein the antiglare layer collides the fine particles to form nonuniforms on the polished metal plate. By electroless nickel plating on the nonuniform surface of the metal plate to reduce the depth of the nonuniformities forming the mold, and by moving the surface nonuniformities of the mold to the surface of the transparent resin film. Here, the transparent resin film may be a film of UV curable resin or thermoplastic resin.

The liquid crystal display of the present invention has good antiglare properties and also achieves high contrast and thus is excellent in terms of visibility and brightness of the displayed image. The antiglare polarizing film stack of the present invention has fine non-uniformities on the surface but low haze in order to achieve antiglare properties. Therefore, the anti-glare polarizing film stack of the present invention can achieve a high contrast ratio when applied to a liquid crystal display, in particular, a VA mode liquid crystal display.

The invention will be explained with reference to the accompanying drawings.

Referring to FIG. 1, the liquid crystal display of the present invention includes a liquid crystal cell 10, a pair of linear polarizers 20 and 21 sandwiching the liquid crystal cell 10, and one of the linear polarizers and the liquid crystal cell 10. ) And a first retardation plate 26 positioned between. The liquid crystal cell 10 includes a pair of cell substrates 11 and 12 and a liquid crystal layer 17 sandwiched between the cell substrates 11 and 12, the cell substrates 11 and 12 facing each other. It has individual electrodes 14 and 15 on the viewing side. In the liquid crystal layer 17 of the liquid crystal cell 10, the molecules of the liquid crystal are usually oriented (or arranged) from one substrate to another in a direction substantially perpendicular to the substrates near the substrates when no voltage is applied. do). That is, the liquid crystal cell 10 is a so-called vertical array (VA) mode liquid crystal cell.

n_z) 또는 2 축 판 (n_x > n_y > n_z) 이다. 제 1 지연판 (26) 은 지연판의 위상 지연축이 인접한 선형 편광자 (20 또는 21) 에 실질적으로 평행하거나 실질적으로 수직하도록 위치된다. 그것에 의하여, 광의 누설이 억제될 수 있다. 여기에서, 표현 "실질적으로 평행" 또는 "실질적으로 수직" 에서의 용어 "실질적으로" 는, 완벽하게 평행 또는 정확하게 수직이 요구되지만, 평행 방향 또는 수직 방향에서 ±5 도의 편차는 허용되는 것을 의미한다. 바람직한 실시예에서, 제 1 지연판 (26) 은 지연판의 위상 지연축이 인접한 선형 편광자의 투과축에 실질적으로 평행하도록 위치된다.The first retardation plate 26 has refractive indices satisfying the relationship n _x > n _y ≧ n _z , where n _x and n _y are the main refractive indices in the film plane and n _z is the refractive index in the thickness direction of the film. Here, the main refractive indices in the film plane are in a direction perpendicular to the refractive index and phase retardation axis direction in the direction in which the refractive index is maximized in the film plane (phase retardation axis direction), that is, the direction in which the refractive index is minimized (phase advance axis). The former is represented by n _x , while the latter is represented by n _y . Thus, the first retardation plate 26 is a shortened plate (n _x > n _y

n _z ) or biaxial plates (n _x > n _y > n _z ). The first retardation plate 26 is positioned such that the phase retardation axis of the retardation plate is substantially parallel or substantially perpendicular to the adjacent linear polarizer 20 or 21. By this, leakage of light can be suppressed. Here, the term "substantially" in the expression "substantially parallel" or "substantially vertical" means that perfectly parallel or exactly vertical is required, but a deviation of ± 5 degrees in the parallel or vertical direction is allowed. . In the preferred embodiment, the first retardation plate 26 is positioned such that the phase retardation axis of the retardation plate is substantially parallel to the transmission axis of the adjacent linear polarizer.

n_y > n_z 의 관계를 만족시키는 굴절률들을 가지며, n_x, n_y 및 n_z 는 상술한 것과 동일하다. 이것은 제 2 지연판 (27) 은 수직선 방향으로의 광학축 및 (-) 단축을 가진 막, 즉, c-판이라는 것을 의미한다. 여기에서, "n_x

n_y" 는 n_x 이 정확히 n_y 과 같고, 즉, 공식 (1) 에 의해서 표현된 면내 (in-plane) 지연값 R₀ 이 0 (영) 이지만, 면내 배열은 현실적으로 무시되고, 즉, 면내 지연값은 대략 10 nm 이내이며, 바람직하게는 대략 5 nm 라는 것을 의미한다.According to the invention, the second retardation plate 27 is formed on the face (FIGS. 1A and 1B), or between the cell substrate and the linear polarizer 21 or 20 opposite the first retardation plate 26. 1 is positioned between the retardation plate 26 and the liquid crystal cell 10 (FIGS. 1C and 1D). The second retardation plate 27 is n _x

have refractive indices satisfying the relationship n _y > n _z , and n _x , n _y and n _z Is the same as described above. This means that the second retardation plate 27 is a film having an optical axis and a negative axis in the vertical line direction, that is, a c-plate. Where "n _x

n _y "says that n _x is exactly equal to n _y , that is, the in-plane delay value R ₀ represented by formula (1) is 0 (zero), but the in-plane array is practically ignored, i.e., in-plane It means that the retardation value is within about 10 nm, preferably about 5 nm.

In addition, according to the present invention, the antiglare layer 30 having a specific surface shape and imparting specific optical properties to the liquid crystal display is the surface of one linear polarizer 20 opposite to the surface facing the liquid crystal cell 10, namely , On the surface on the display side (field of view). The antiglare layer has an antiglare surface formed with numerous fine nonuniformities and has three optical frequencies consisting of hazes of less than 5% of normal incident light, and dark and bright lines having widths of 0.5 mm, 1.0 mm and 2.0 mm, respectively. When measured at an angle of incidence of 45 degrees of light using combs, the reflectance R (30) at an angle of incidence of less than 50% and an angle of incidence of 30 degrees of less than 2% of incident light entering an angle of incidence of 30 degrees, and incident light entering an angle of incidence of 30 degrees Reflectivity R (40) at a reflection angle of 40 degrees less than or equal to 0.003% relative to and R (30) less than or equal to 0.001 when R (≥60) reflectance in any direction at a reflection angle of 60 degrees or greater relative to incident light entering a 30 degree incidence angle ) has a ratio of R (≥60), the surface of the antiglare layer is 50 ㎛ ² with a mean surface area, preferably from 300 to 1500 ㎛ of ㎛ ^{2 2} to ² for 1,000㎛ Composed of brothers and, polygons are formed by Voronoi division on the surface using the vertices of the convex parts of the surface non-uniform stained deulrosseo generatrix. The antiglare layer will be described in detail below.

In FIG. 1, when the antiglare layer 30 and the display side linear polarizer 20 are laminated, and the retardation plates 26 and 27 are provided on the display side with respect to the liquid crystal cell 10, the display side linear polarizer ( 20 and retardation plates 26 and / or 27 are shown as antiglare polarizing film stacks 40 or 41. When the linear polarizer 21 and the retardation plates 26 and / or 27 are provided on the back side of the liquid crystal cell 10, the linear polarizer 21 and the retardation plates 26 and / or 27 are back anti-glare polarization. It is shown as a film stack 50.

The anti-glare polarizing film stack 40 or 41 and the liquid crystal cell 10, and the back polarizer 21 or the back polarizing film stack 50 and the liquid crystal cell 10 are usually attached with an adhesive 60. As the adhesive, one having good transparency such as an acrylic adhesive is usually used. Typically, the backlight 70 is provided on the back polarizer 21 to provide light to the liquid crystal cell.

The linear polarizers 20 and 21 allow the linear polarization oscillating in one of two directions perpendicular to the membrane plane to pass, but the linear polarization oscillating in the other of the two directions may be a commonly used polarizing film or plate that absorbs. have. Particular examples of such linear polarizers are polyvinyl alcohol films which have been dyed with high dichromatic dyes and shortened crosslinked with boric acid. Iodine-based polarizers containing iodine as high dichrome dyes or dye-based polarizers containing organic dichromium dyes as high dichrome dyes can be used. The linear polarizer may be a polyvinyl alcohol type polarizer, or a polyvinyl alcohol type polarizer having a protective film of a transparent polymer such as triacetyl cellulose on at least one surface.

Since the antiglare layer 30 is provided on one surface of the display side linear polarizer 20, the antiglare layer may function as a protective film of the display side linear polarizer 20. When the retardation plate 26 or 27 is provided on one surface of the display side linear polarizer 20, the retardation plate may function as a protective film of the linear polarizer. An antiglare layer 30 is provided on one surface of the surface side linear polarizer 20, and another surface of the surface side linear polarizer 20 is applied to the liquid crystal cell 10 with the adhesive 60 as shown in FIG. 1D. When directly attached, the above-described protective film is at least provided to the linear polarizer 20 opposite to the antiglare layer 30.

When the retardation plate 26 or 27 is provided on one surface of the rear polarizer 21, as shown in FIGS. 1A, 1B, and 1D, the retardation plate will function as a protective film of the linear polarizer 21. It may be. In this case, the above-mentioned protective film is preferably provided on the other surface of the linear polarizer 21. When no layer such as a retardation plate is laminated on the rear linear polarizer 21, the above-described protective films are preferably provided on both surfaces of the linear polarizer 21.

The first retardation plate 26 has a refractive index that satisfies the relationship n _x > n _y ≥ n _z , where n _x , n _y And n _z are as defined above. The in-plane delay value R ₀ is selected in the range of 30 to 300 nm depending on the characteristics of the liquid crystal cell 10 and the like. Preferably, the ratio of R ₀ to R _th exceeds 1 but does not exceed 2. A retardation plate having such a property may be produced by uniaxially or biaxially stretching a transparent resin film having positive anisotropic refractive indices under appropriate conditions. Examples of transparent resins with positive anisotropic refractive indices include acylated celluloses such as cyclic olefin resins, polycarbonates, and the like. The cyclic olefin resin is a resin containing a cyclic olefin such as norbornene, dimethanooctahydrohaphthalene, etc. as a monomer. Examples of commercially available cycloolefin polymers are ARTON ™ (available by JSR Corporation), ZEONOR® and ZEONEX® (both available by ZEON Corporation) and the like. Among these transparent resins, triacetyl cellulose and cyclic olefin resins are preferably used because they have a low photoelastic coefficient and result in less deformation of in-plane properties due to thermal deformation under use conditions.

n_y > n_z 의 관계를 만족시키는 굴절률들을 가지며, 여기에서, n_x, n_y 및 n_z 는 상기 정의한 바와 동일하다. 그러한 지연 특성은, 기판 상에 디스코틱 (discotic) 액정을 코팅하는 것에 의해서, 좁은 피치로 기판 상에 콜레스테릭 (cholesteric) 액정을 코팅하는 것에 의해서, 기판 상에 운모와 같은 무기화합물의 층을 형성하는 것에 의해서, 연속적으로 또는 계속적으로 2 축으로 레진막을 연신시키는 것에 의해서 또는 비연신된 용매-캐스트 막을 제공하는 것에 의해서 성립될 수도 있다. 제 2 지연판 (27) 은 바람직하게는 0 내지 10 nm 의 R₀ 및, 50 내지 300 nm 의 R_th 를 가진다. 지연판 (27) 의 물질 또는 지연판 (27) 의 기판의 물질은 제한되지 않는다. 바람직하게는, 지연판 (27) 은 자유롭게 형성될 수 있고 R_th 이 쉽게 저비용에서 제어될 수 있는 화합물의 층을 가진다. 그러한 지연 특성들을 가진 상용가능 지연판들의 예들은 "VAC 막" (상표명, Sumitomo Chemical Co., Ltd. 에 의해 사용가능), "FUJITAC" 막 (상표명 FUJIFILM Corporation 에 의해 사용가능) 등을 포함한다. 제 2 지연판 (27) 은 n_x

n_y 의 굴절률 관계를 가지며 따라서 대략 0 (영) 의 R₀ 을 가지기 때문에, 제 2 지연판이 매우 작은 R₀ 을 가질 때에도, 위상 지연축의 축 각도를 정의할 필요가 없다.The second retardation plate 27 is n _x

have refractive indices that satisfy the relationship n _y > n _z , where n _x , n _y and n _z are as defined above. Such retardation properties can be achieved by coating discotic liquid crystals on the substrate and coating cholesteric liquid crystals on the substrate with a narrow pitch to form a layer of an inorganic compound such as mica on the substrate. By forming, by stretching the resin film continuously or continuously biaxially, or by providing a non-stretched solvent-cast film. The second retardation plate 27 preferably has R ₀ of 0 to 10 nm and R _th of 50 to 300 nm. The material of the retardation plate 27 or the material of the substrate of the retardation plate 27 is not limited. Preferably, the retardation plate 27 has a layer of compound which can be freely formed and R _th can be easily controlled at low cost. Examples of commercially available retarders with such retardation characteristics include "VAC membrane" (trade name, available by Sumitomo Chemical Co., Ltd.), "FUJITAC" membrane (available by trade name FUJIFILM Corporation), and the like. The second retardation plate 27 is n _x

Since it has a refractive index relationship of n _y and thus has a R ₀ of approximately 0 (zero), it is not necessary to define the axial angle of the phase retardation axis even when the second retardation plate has a very small R ₀ .

The embodiment of the liquid crystal display shown in FIG. 1A shows a liquid crystal cell 10, an antiglare polarizing film stack 40 on one surface (display surface) of the liquid crystal cell 10, and another surface (back side) of the liquid crystal cell 10. ), The back side polarizing film layered layer 50 is included. In this embodiment, the antiglare polarizing film stack 40 includes the antiglare layer 30, the linear polarizer 20 and the first retardation plate 26, which are ordered from the farthest side in the liquid crystal cell 10. The back side polarizing film stack 50 includes a second retardation plate 27 and a linear polarizer 21, which are stacked in order from the side closest to the liquid crystal cell.

The embodiment of the liquid crystal display shown in FIG. 1B shows a liquid crystal cell 10, an antiglare polarizing film stack 40 on one surface (display side surface) of the liquid crystal cell, and another surface (back side) of the liquid crystal cell 10. And a back side polarizing film stack 50 on it. In this embodiment, the anti-glare polarizing film stack 40 includes the anti-glare layer 30, the linear polarizer 20 and the second retardation plate 27, which are laminated in order from the side closest to the liquid crystal cell. The difference between the embodiment of FIG. 1A and the embodiment of FIG. 1B is that the positions of the first retardation plate 26 and the second retardation plate 27 are reversed.

The embodiment of the liquid crystal display shown in FIG. 1C shows a liquid crystal cell 10, an antiglare polarizing film stack 40 on one surface (display side surface) of the liquid crystal cell, and another surface (back side) of the liquid crystal cell 10. Linear polarizer 21. In this embodiment, the anti-glare polarizing film stack 40 includes the anti-glare layer 30, the linear polarizer 20, the first retardation plate 26 and the second retardation plate 27, which are the most in the liquid crystal cell. Stacked in order from the far side.

The embodiment of the liquid crystal display shown in FIG. 1D is provided on the liquid crystal cell 10, the antiglare polarizing film stack 41 on one surface (display side surface) of the liquid crystal cell, and on the other surface (back side) of the liquid crystal cell 10. The back side polarizing film layered 50 is included. In this embodiment, the antiglare polarizing film stack 41 includes an antiglare layer 30 and a linear polarizer 20, which are laminated in order from the side furthest from the liquid crystal cell, and the back side polarizing film stack 50 Includes a second retardation plate 27, a first retardation plate 26 and a linear polarizer 21, which are stacked in order from the side closest to the liquid crystal cell. In the embodiment of FIG. 1C, a stack of the linear polarizer 20, the first retardation plate 26 and the second retardation plate 27 is provided on the display surface side of the liquid crystal cell 10, and the antiglare layer 30 is Provided on the linear polarizer 20, whereas in the embodiment of FIG. 1D, the stack of the second retardation plate 27, the first retardation plate 26 and the linear polarizer 21 is formed of the liquid crystal cell 10. It is provided on the back side, and no retardation plate is provided on the display surface side of the liquid crystal cell 10.

n_y > n_z 의 관계를 가진 굴절률들을 가진 지연판 (즉, 상술한 제 2 지연판) 일 수도 있으며, n_x, n_y 및 n_z 는 상기 정의한 것과 동일하다.In the anti-glare polarizing plate of the present invention, the anti-glare layer 30, the linear polarizer 20 and the retardation plates 26 and / or 27 are laminated in order as shown in Figs. 1A, 1B and 1C. The cross-section of the anti-glare polarization stack 40 is shown schematically in FIG. 2 alone, and the retardation plate 25 represents the first retardation plate 26 and / or the second retardation plate 27. That is, the retardation plate 25 is a retardation plate (ie, the first retardation plate described above) having refractive indices satisfying the relationship of n _x > n _y ≧ n _z , or n _x

It may be a retardation plate (ie, the second retardation plate described above) having refractive indices having a relationship of n _y > n _z , where n _x , n _y and n _z are the same as defined above.

n_y > n_z 의 관계를 만족시키는 굴절률들을 가진 제 2 지연판이 도 3 에 도시된 것처럼 적층된다. 이 실시예에서, 제 1 지연판 (26) 이 선형 편광자 (20) 를 접하며 지연판의 위상 지연축이 선형 편광자 (20) 의 투과축에 실질적으로 평행하거나 실질적으로 수직하도록 위치된다.Optionally, first retardation plate 26 and n _x having refractive indices satisfying a relationship of n _x > n _y ≧ n _z

A second retardation plate with refractive indices satisfying the relationship of n _y > n _z is stacked as shown in FIG. 3. In this embodiment, the first retardation plate 26 abuts the linear polarizer 20 and is positioned such that the phase retardation axis of the retardation plate is substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer 20.

The anti-glare layer 30 has an anti-glare surface formed with fine non-uniformities, and has three constituents of haze that is 5% or less for vertical incident light, and dark and bright lines having a width of 0.5 mm, 1.0 mm and 2.0 mm, respectively. When measured at an angle of incidence of 45 degrees of light using optical frequency combs, the reflectance R (30) at an angle of incidence of less than 50% and a reflection angle of 30 degrees of less than 2% of incident light entering an angle of incidence of 30 degrees and an angle of incidence of 30 degrees A reflectance R (40) at a reflection angle of 40 degrees that is 0.003% or less with respect to the incoming incident light, and R that is 0.001 or less when R (≥60) is a reflectance in any direction at a reflection angle of 60 degrees or greater with respect to the incident light entering the 30 degrees of incidence the surface of the antiglare layer has a ratio of R (≥60) of the 30 polygonal having an average surface of 50 ㎛ ² to 1500 ㎛ ² small, preferably from ² to 300 ㎛ 1,000㎛ ² Is composed of, polygons using the vertex of the convex portion of the surface non-uniform stained deulrosseo generatrix is formed by Voronoi division on the surface.

Now, the antiglare layer 30 is described. The antiglare layer 30 is preferably manufactured by the method to be described below, and has an antiglare surface on which fine nonuniformities are formed, and a haze of 5% or less with respect to vertical incident light. Although the anti-glare layer 30 has fine non-uniformities formed on the surface, when the anti-glare layer 30 is applied to the liquid crystal display, it has a low haze and can therefore suppress the reduction in contrast.

The antiglare layer 30 has a total reflection resolution of 50% or less for the incident light of 45 degrees. The reflection resolution may be measured by the method described in JIS K 7105. In the method of JIS K 7105, four optics consisting of dark and bright lines, each having a width of 0.125 mm, 0.5 mm, 1.0 mm and 2.0 mm (the ratio of the width of the dark line to the width of the light line is 1: 1) Frequency combs are defined and used. In the present invention, among the reflection resolutions measured using the four optical frequency combs, the value of the reflection resolution obtained using the optical frequency comb for the antiglare layer according to the present invention measured as 0.125 mm has a relatively large error. Since small enough, those obtained using optical frequency combs with a width of 0.125 mm are not summed. Thus, in the present invention, the total reflection resolution is the sum of the reflection resolutions measured using three optical frequency combs consisting of dark and bright lines with widths of 0.5 mm, 1.0 mm and 2.0 mm, respectively. Therefore, the maximum possible value of the full resolution according to the resolution is 300%. When the total reflection resolution exceeds 50%, images such as images of the light source are reflected to such an extent that the antiglare characteristics of the antiglare polarizing film stack of the present invention are degraded.

If the total resolution is 50% or less, each reflection resolution measured using respective optical frequency combs with widths of 0.5 mm, 1.0 mm and 2.0 mm is such that variations in reflection resolution due to measurement errors cannot be ignored. , Since it is almost about 10 to 20%, it may be difficult to evaluate the superiority of the anti-glare characteristic only at the total reflection resolution when the total reflection resolution is 50% or less.

Therefore, the dependence of the reflectance on the reflection angle, which is used as another standard for evaluating anti-glare characteristics, is described with reference to FIGS. 4 and 5. 4 is a schematic perspective view showing an incidence direction and a reflection direction of light with respect to the antiglare layer (antiglare layer). According to the present invention, R (30) is incident to the incident light 36 entering the angle of 30 degrees from the vertical line 35 of the antiglare layer 30 in the direction of the reflection angle of 30 degrees, that is, the spherical 37 When defined as the reflectance of the reflected light, R 30 is less than or equal to 2%. The specular reflectance R (30) is preferably 1.5% or less, and more preferably 0.7% or less. When the specular reflectance R 30 exceeds 2%, the antiglare layer may not have enough antiglare properties to reduce the visibility of the display. In FIG. 4, the direction of the reflected light at any angle θ is indicated by the number 38, and the directions 37 and 38 of the reflected light during the measurement of the reflectance change the vertical line 35 of the film and the direction 36 of the incident light. It is present in the containing plane 39.

FIG. 5 is an example of a graph showing the reflectance of the reflected light 38 with respect to the incident light 36 entering at an angle of 30 degrees from the vertical line 35 of the antiglare layer 30 of FIG. 4 with respect to the reflection angle. A graph showing the relationship between reflectance and reflection angle, ie, the reflectance read from the graph at each reflection angle, is called a "reflectance profile". As shown in the graph of FIG. 5, the specular reflectance R (30) is a peak value of the reflectance for the incident light 36 entering at an angle of 30 degrees, and the reflectance tends to decrease as the reflection direction deviates from the specular reflection direction. .

According to the present invention, R 40 is defined as the reflectance of light reflected in a direction at a reflection angle of 40 degrees with respect to incident light 36 entering an angle of 30 degrees in the vertical line 35 of the antiglare layer 30 shown in FIG. 4. R (40) is less than 0.003% when When R 40 exceeds 0.003%, the displayed image tends to whiten. Therefore, R 40 is preferably not so large. When R 40 is too small, the antiglare layer may also not have sufficient antiglare properties. Therefore, R (40) is preferably 0.00005% or more. However, since the reflectance or whitening is subjectively determined by the characteristics and the eyes reflecting the preferences of the users, it may be very difficult to strictly determine the desired range of the R 40.

In addition, according to the present invention, the ratio of R (≥60) to R (30) is 0.001 or less, where R (≥60) is any direction at a reflection angle of 60 degrees or more. This ratio is preferably 0.0005 or less, and more preferably 0.0001 or less. Here, "any direction at a reflection angle of 60 degrees or more" means a reflection angle in the range between 60 degrees and 90 degrees. The antiglare film produced by the method to be described below has the typical reflection profile shown in Fig. 5, and in the case of such a glare film, the reflectivity often has a peak in the specular reflection direction and gradually decreases as the reflection angle increases. Thus, the ratio R (≧ 60) / R (30) may be expressed as the ratio R (60) / R (30), where R (60) is the refractive index at a reflection angle of 60 degrees. When the R (≧ 60) / R (30) ratio exceeds 0.001, the antiglare layer appears so white that the visibility of the display screen is degraded. That is, when a black image is displayed on the display screen by providing an antiglare layer in front of the screen, the entire screen appears white by reflecting external light.

In the case of the reflection profile shown in FIG. 5, the specular reflectivity R (30) is about 0.4%, R (40) is about 0.0006%, and R (60) is about 0.00003%.

In addition to the specific reflection profiles described above, the surface of the antiglare layer according to the present invention has an average area of 50 μm ² to 1500 μm ² , preferably 300 μm ² to 1000 μm ² , wherein the polygons are surface nonuniformities with a parent point. It is formed by the Voronoi division of the surface using the vertices of the convex parts of.

An algorithm for determining the vertices of the convex portions on the nonuniform surface of the antiglare layer is described. When attention is focused on one arbitrary point on the surface of the antiglare layer, there is no point around any point having a height higher than that point, and the height of that arbitrary point on the non-uniform surface is non- If it is higher than the median between the height of the lowest point on the uniform surface and the height of the highest point, then any point is the vertex of the convex portion. Specifically, as shown in FIG. 6, any point 91 on the surface of the antiglare layer is selected. A circle with a radius of 2 μm to 5 μm is drawn using the point 91 as the center of the circle in the plane parallel to the base surface 93 of the antiglare layer. There is no height higher than the height of the point 91 in the circle 94 indicated by projecting the circle drawn on the surface 93 of the antiglare layer, and the height of the point 91 is the height of the lowest point on the non-uniform surface and When it is higher than the median between the heights of the peaks, the point 91 is determined to be the vertex of the convex portion. In this case, the projected circle 94 has a radius at which fine nonuniformities on the sample surface are not calculated, and the circle 94 does not include a plurality of convex portions. Thus, the radius of circle 94 is preferably about 3 μm. By this method, the number of convex parts per unit area of non-uniform surface can also be calculated.

The number of convex parts calculated by the method is preferably 50 to 150 in a field of 200 μm × 200 μm, in order to achieve good visibility without causing reflection or whitening. If the number of convex parts on the non-uniform surface of the antiglare layer is small, the glare may become difficult to see the displayed images, especially when an antiglare polarizing film stack is used in combination with a high resolution display device. Caused by interference with In addition, the texture of the displayed image is degraded. When the number of convex parts is too large, the tilt angle of the shape of the non-uniformity becomes so steep that the image tends to whiten. The number of convex parts in the field of 200 μm × 200 μm is preferably 120 or less and 70 or more.

Now, the Voronoi split will be explained. When several points (i.e., parent points) are distributed in a plane, the shape is a Voronoi shape, which can divide the plane by judging the parent point closest to any point on the plane, and the plane by those shapes The division of is called the Voronoi division. 7 shows an example of Voronoi splitting of the surface of an antiglare layer using the vertices of convex parts on the surface as parent points. In FIG. 7, the points 95 are parent points, and each polygon 96 including one parent point is an area formed by Voronoi division, such a polygon is called a Voronoi area or a Voronoi polygon, Is called the Voronoi polygon. The area 97 shown in black in the rim of FIG. 7 will be described below. In the Voronoi plot, the number of parent points is equal to the number of Voronoi polygons. For the sake of simplicity, the part of the parent point and the part of the polygons are denoted by numbers 95 and 96 of FIG. 7, respectively.

In order to calculate the average area of the Voronoi polygons obtained by Voronoi segmentation using the vertices of the convex parts as the parent point, the surface shape of the antiglare layer is applied with a suitable apparatus such as confocal microscope, interference microscope, atomic force microscope (AFM), etc. Observed and three-dimensional coordinate values are determined. The surface of the antiglare layer is then divided into Voronoi according to the following algorithm, and the average area of the Voronoi polygons is calculated. That is, the vertices of the convex portions on the nonuniform surface of the antiglare layer are determined according to the algorithm, and then the vertices of the convex portions are projected onto the base surface of the antiglare layer. Then, all three-dimensional coordinates obtained by measuring the surface shape are projected on the base surface, and all projected points are assigned to the nearest spiral models to perform Voronoi segmentation. The areas of all Voronoi polygons are calculated and averaged to obtain the average area of Voronoi polygons. In this measurement, the area of Voronoi polygons close to the periphery of the measured field of view is calculated to minimize the error. That is, in the case of FIG. 7, the blackened Voronoi polygons 97 close to the periphery of the measurement field of view are not included in the calculation of the average area. In addition, in order to minimize the measurement error, the average values of the Voronoi polygons are calculated in three or more fields each having a field of 200 μm × 200 μm, and all average values are averaged back to the measured values and used.

As described above, in the present invention, the average area of the Voronoi polygons having the apex of the convex portions on the nonuniform surface of the antiglare layer as the parent point is 50 µm ² to 1,500 µm ² , preferably 300 µm ² to 1,000 µm ^2. to be. When the average area of the Voronoi polygons is less than 50 μm ² , the tilt angle of the shape of the surface non-uniformity of the antiglare layer is so steep that the image tends to whiten. When the average area of the Voronoi polygons exceeds 1,500 μm ² , the non-uniform surface shape of the antiglare layer becomes rough, especially when glare occurs when the antiglare polarizing film stack is used in combination with a display device having a high resolution. , The texture of the image is degraded.

Using the three-dimensional coordinates measured here, the maximum cross-sectional height Pt and the arithmetic mean height Pa of the cross-sectional curve, defined by JIS B 0601 (= ISO 4287), can be calculated. In addition, the height of each point on the nonuniform surface of the antiglare layer can be expressed in the form of a histogram. In order to achieve good visibility without causing reflection or whitening, the arithmetic mean height Pa of the cross-sectional curve is preferably 0.08 µm to 0.15 µm, and the maximum cross-sectional height Pt is preferably 0.4 µm to 0.9 µm. When the arithmetic mean height Pa is smaller than 0.08 mu m, the surface of the antiglare layer becomes substantially flat such that it does not have any antiglare property. When the arithmetic mean height Pa exceeds 0.15 mu m, the surface shape of the antiglare layer becomes rough, causing problems such as whitening and glare. When the maximum cross-sectional height Pt is 0.4 µm or less, the surface of the antiglare layer becomes flat so as not to have any antiglare property. When the maximum cross-sectional height Pt exceeds 0.9 µm, the surface shape of the antiglare layer again becomes rough, causing problems such as whitening and glare.

When the heights of the points on the non-uniform surface of the antiglare layer are drawn in the form of a histogram, the peaks of the histogram are preferably intermediate between the height of the lowest point (0% height) and the height of the highest point (100% height) on the non-uniform surface. It is in the range of ± 20% from the value (50% height). This means that the peak of the histogram is preferably in the range between 30% and 70% of the height difference between the height of the highest point and the height of the lowest point. If the peak is not present in the range of ± 20% from the median, that is, in the range of less than 30% or greater than 70% of the height of the peak, the surface shape of the antiglare layer becomes rough, which is undesirable. Glare tends to occur. In addition, the texture of the appearance tends to be lowered.

To draw a histogram of the heights, the highest and lowest points of the height on the surface of the antiglare layer (glare layer) are determined, and then the difference between the height of the lowest point and the height of each measured point (ie, the height of the measured point). Is divided by the difference between the height of the lowest point and the height of the highest point (ie, the largest height difference) to obtain the relative height of each point. Therefore, the obtained relative height is plotted as a histogram with the highest height of 100% and the lowest height of 0% in order to obtain the peak position of each point in the histogram. The histogram should be divided into sections to avoid the effects of error in the data, and is generally divided into about 10-30 sections. For example, the entire region from the lowest point (0% height) to the highest point (100% height) is divided by 5% intervals, and the position of the peak is determined.

The antiglare surface constituting the antiglare layer having the above-described properties has a shape covered by non-uniform materials having substantially no flat plane. An anti-glare surface with such a surface shape is preferably such as to collide fine particles to form non-uniformities on the polished metal plate, electroless nickel plating on the non-uniform surface of the metal plate to form the mold, the surface of the mold The non-uniformities may be prepared by moving the surface non-uniformity of the mold to the surface of the transparent resin film, and removing the transparent resin film with the non-uniformities moved from the mold.

A preferred method of manufacturing the antiglare layer (antiglare film) by the above-described method is described with reference to Fig. 8, which shows that in the mold using a metal plate as the mold body from the manufacturing step of the mold with non-uniformities on the surface. The cross sections of the steps up to the movement of the non-uniformity into the resin film are schematically shown. 8A shows a cross section of a metal plate 81 after specular polishing, with a polished surface 82. The polished surface 82 of the metal plate 81 impinges (blasts) the fine particles to form nonuniformities on the surface 82. 8B schematically shows the cross section on the metal plate 81 after the collision, which has a hemispherical fine concave portion 83. Next, the surface with nonuniformities formed by the particulate impact is electroless plated with nickel to reduce the depth of the nonuniforms. 8C schematically shows a cross section of the metal plate 81 after electroless plating of nickel. In FIG. 8C, the nickel plating layer 84 is formed on the surface of the metal plate 81 having the fine concave portions, and the surface 83 of the nickel plating layer 84 has a depth compared to the surface 83 of FIG. 8B. It has non-uniformities that are reduced by electroless plating of nickel, ie the non-uniform shape of the surface of the metal plate becomes dull. Thus, when the hemispherical finely concave surface 83 of the metal plate 81 is electroless plated with nickel, a mold having non-uniformities suitable for producing an antiglare film having desirable optical properties and having no flat top view is obtained. Can be.

FIG. 8D schematically illustrates the step of moving non-uniformities of the mold of FIG. 8C formed in the previous step to the resin film. FIG. That is, the resin film is formed on the nonuniform surface of the nickel plating layer 84. By this, a film 30 having a moved non-uniform shape is obtained. The film 30 may be composed of a single film of thermoplastic transparent resin. In this case, in the heated state, the thermoplastic resin film is applied to the nonuniform surface 86 of the mold and molded by thermal pressing. Alternatively, as shown in FIG. 8D, the film 30 may be composed of a transparent substrate film 32 and an ionization curable resin layer 33 laminated on the surface of the substrate film 32. In this case, the ionizing radiation curable resin layer 33 comes into contact with the non-uniform surface 86 of the mold and is spun by ionizing radiation to cure the resin layer 33. Thereby, the non-uniform shape of the mold is moved to the ionization radiation curable resin layer 33. Such films will be described in detail below. 8E shows a cross section of the film 30 after it is removed from the mold.

In the method shown in FIG. 8, preferred embodiments of the metal used for the manufacture of the mold include aluminum, iron, copper, stainless steel, and the like. Among them, metals which are easily deformed by colliding fine particles, that is, those which do not have too large a hardness, are preferable. In particular, aluminum, iron, copper or the like is preferably used. In terms of cost, aluminum and wrought iron are more preferred. The mold may be in the form of a flat metal plate or a cylindrical metal roll. When a roll-shaped mold is used, the antiglare film can be produced continuously.

Metals with a polished surface collide or blast the fines. In particular, the metal is preferably a mirror because often the metal plate or roll is machined, for example by cutting or grinding, to achieve the desired accuracy, whereby processing marks are often left on the surface of the metal body. Polished close to the surface. If a deep mark remains, the surface of the metal body may still have traces of marks after impinging the fine particles on the metal surface, since the depth of some marks is wider than the depth of the non-uniformities formed by the collision of the particles. Traces of these may unintentionally affect the optical properties of the antiglare layer.

The method of polishing the metal surface is not limited, and any mechanical polishing, electrolytic polishing, and chemical polishing may be used. Examples of mechanical polishing include superfinishing, lapping, fluid polishing, buffing, and the like. The surface roughness of the metal surface after polishing is 1 µm or less, preferably 0.5 µm or less, and more preferably 0.1 µm or less by the centerline average surface roughness Ra. When Ra is too large, the influence of the surface roughness before deformation may remain after the deformation of the metal surface by the collision of fine particles. The lower limit of Ra may not be limited, but may be realistically limited in terms of processing time, processing cost, and the like.

The method of impinging the fine particles on the metal surface is preferably a blasting processing method. Examples of blasting processing methods include sand blasting, shotblasting, liquid honing, and the like. As the particles used in these processing methods, those with shapes close to the sphere are more preferable than those with sharp edges. Moreover, particles of hard material are preferred because they do not break during processing to form sharp edges. Preferred examples of ceramic particles which satisfy such particles are spherical zirconium oxide beads, aluminum beads and the like. Preferred examples of metal particles are beads made of steel, stainless steel and the like. Moreover, particles comprising ceramic or metal beads held on a resin binder may be used.

Particles with an average particle size of 10 to 75 μm, preferably 10 to 35 μm, in particular spherical fine particles, when used as fine particles to impinge on the metal surface, 50 to 1,500 μm ² , preferably 300 to 1,000 An antiglare film can be produced, comprising shape factors comprising the average area of the defined Voronoi polygons according to the invention in the range of μm ² . As the fine particles, particles having a constant particle size, ie, monodisperse particles, are particularly preferred. When the average particle size of the fine particles is too small, it is difficult to form satisfactory nonuniformities on the metal surface. Also, the tilt angle of the shape of the non-uniformity is so steep that the image tends to whiten. When the average particle size of the fine particles is too large, the surface nonuniformities become rough enough to cause glare and degrade the texture of the image.

The metal surface with nonuniformities formed by the method described above is then electroless plated with nickel to reduce the depth of the nonuniformities. The degree of depth reduction depends on the type of metal, the depth and size of nonuniformities formed by blasting, the type and thickness of the plated nickel, and the like. The most important factor controlling the degree of depth reduction may be the thickness of the plated nickel. If the thickness of the electroless plating nickel is too small, the depth of the nonuniformities formed by blasting or the like is not effectively reduced, so that the optical properties of the antiglare film with the nonuniformities moved from the mold cannot be sufficiently improved. When the thickness of the electroless plating nickel is too large, the productivity decreases. Therefore, the thickness of electroless plating nickel becomes like this. Preferably it is about 3-70 micrometers, More preferably, it is 5 micrometers or more and 50 micrometers or less.

In order to form a plating layer on the metal surface, electroless plating, in particular, electroless nickel plating which provides a plating layer with a high hardness, is used, which forms a plating layer having a macroscopic constant thickness on the surface of the metal plate or roll is used. do. Preferred examples of electroless nickel plating are polished nickel using a plating bath containing a polishing agent such as sulfur, nickel-phosphorus alloy plating (low phosphorus type, medium phosphorus type or high phosphorus type), nickel-boron alloy plating, and the like. Plating.

If hard chromium plating, in particular electrolytic chromium plating, as described in JP-A-2002-189106 is used, the electric field tends to concentrate on the edges of the metal plate or roll such that the thickness of the plated metal varies between the center and the edges. . Therefore, if nonuniforms having a constant depth are formed by blasting or the like on the entire surface of the metal plate or roll, the degree of depth reduction by plating may vary from place to place on the surface of the metal plate or roll, and as a result, is nonuniform. The depth of the water changes. Therefore, electrolytic plating is not preferably used in the present invention.

In addition, hard chromium plating may form a rough surface and, therefore, is not suitable for production of a mold for producing an antiglare layer. To remove the rough surface, the surface of hard chromium plating is usually polished. However, polishing of the plated surface is not preferred in the present invention as described below.

However, the present invention does not block the formation of thin chromium plating, ie the so-called flash chromium plating, on the outermost surface after electroless nickel plating in order to increase the surface strength. When flash chromium plating is performed, the thickness of the flash plated chromium layer is as small as possible to avoid distortion of the shape of the electroless plated nickel layer as a primer, preferably 3 μm or less, more preferably, 1 micrometer or less.

In addition, polishing a metal plate or a roll after plating as disclosed in JP-A-2004-90187 is not preferable in the present invention. Once the plated surface is polished, the outermost surface may have flat portions that are hardly controlled with good reproducibility such that the optical properties of the antiglare layer are degraded, and the shape of the non-uniformities increases the number of shape control elements. As a result, it is hardly controlled with good reproducibility. 9 shows a metal plate formed by polishing a surface with non-uniformities formed by flat planes impinging fine particles, where the depth of the non-uniforms is reduced by electroless nickel plating. That is, FIG. 9 corresponds to the electroless plating metal plate of FIG. 8C in which the surface of the nickel plating layer 84 is polished. As a result of the polishing, some of the convex portions of the surface nonuniformities 86 on the nickel plating layer 84 formed on the metal plate 81 are ground, whereby flat planes 89 are formed.

According to the present invention, a mold having nonuniformities formed on the surface shown in FIG. 8C is used, and the shape of the nonuniforms is moved to the surface of the film 30 to form an antiglare surface. In this case, the surface shape of the mold can be moved to the film surface by any conventional method. For example, the thermoplastic resin film is thermally pressurized to the nonuniform surface 86 of the mold to move the surface nonuniformities of the mold to the surface of the resin film; The ionized radiation curable resin is coated on the surface of the transparent resin film, and then the ionized radiation curable resin in the uncured state is weakly attached to the non-uniform surface 86 of the mold and the transparent resin film is used to cure the ionizing radiation curable resin. The surface non-uniformities of the mold are transferred to the surface of the ionized radiation curable resin that is radiated and cured through ionization radiation. After the movement, the film is removed from the mold as shown in FIG. 8E to obtain the antiglare film 30. The latter method using ionized radiation curable resins is preferably used in view of mechanical strength such as prevention of surface defects.

The transparent resin used in the latter method may be any film having substantially optical transparency. Specific examples of transparent resins include cellulose resins (ie, triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, etc.), cycloolefin polymers, polycarbonates, polymethyl methacrylates, polysulfones , Polyether sulfone, polyvinyl chloride and the like. Cycloolefin polymers are polymers comprising monomers and cyclic olefins such as norbornene, dimethanooctahydrohaphthalene and the like. Examples of commercially available cycloolefin polymers include ARTON ™ (available by JSR Corporation), ZEONOR® and ZEONEX® (All of which can be used by ZEON Corporation).

Among them, transparent resin films having thermoplastics such as polymethyl methacrylate, polycarbonate, poly sulfone and polyether sulfone and cycloolefin polymer are pressed or pressure bonded to a mold having surface non-uniformities at a suitable temperature, and then It is peeled off the mold, thereby moving the surface nonuniformities of the mold to the film surface. In addition, the polarizing plate is used as a transparent film and the surface nonuniformities of the mold can be moved directly to the surface of the polarizing plate.

When ionized radiation curable resins are used to move surface non-uniformities of the mold, preferably a polymer of a mixture having one or more acryloyloxy groups in the molecule is used. In order to increase the mechanical strength of the antiglare layer, an acrylate having three or more functions, that is, a mixture having three or more acryloyloxy groups is more preferably used. Specific examples of such mixtures include trimetholpropane triacrylate, trimetholethane triacrylate, glycerin triacrylate, pentaerythritol triacrylate, pentaerythritol tetra acrylate, dipentaerythritol hexaacrylate, and the like. Include. In order to impart flexibility to the antiglare layer to prevent breakage of the antiglare layer, an acrylate having an intramolecular urethane bond is preferably used. Specific examples of such acrylate mixtures include diisocyanate mixtures of two molecules of a mixture having at least one hydrooxyl group in addition to the acryloyloxy group in the molecule (ie, trimetholpropane diacrylate, pentaerythritol triacrylate, etc.). It is a urethane acrylate which has a structure added to (ie, hexamethylene diisocyanate, toylene diisocyanate, etc.). In addition, other acrylic resins that have been polymerized and cured rapidly by ionizing spinning, such as ether acrylate polymers, ester acrylate polymers, and the like, may also be used.

In addition, cationic polymerizable polymerizable ionizing radiation curable resins such as epoxy resins, oxetane resins, and the like may be used as the resin to which non-uniformities are given after curing. In this case, one example of a cationicly polymerizable ionizable radiation curable resin is 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, bis (3-ethyl-3-jade Cationic photopolymerizable multifunctional oxetane mixtures such as cetanylmethyl) ether and the like and cationic photopolymer initiators such as (4-methylphenyl) [4- (2-methylpropyl) phenyl) iodonium hexafluorophosphate It may be prepared from a mixture.

When the ionized radiation curable acrylic resin is cured by radiation of UV rays, a UV radical polymerization initiator is used, which generates radicals by radiation of UV rays to initiate the polymerization and curing reaction. UV rays are usually emitted from the side of a glass mold or a transparent resin film. Thus, a polymerization initiator that initiates a radical generation reaction in the range of visible to UV rays, in order to initiate a radical generation reaction within a wavelength range where light can pass through the membrane when UV rays are emitted from the side of the transparent resin film. Is used.

Examples of UV ray radical polymerization initiators that initiate radical production reactions by radiation of UV rays include 1-hydrooxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino Propan-1-one, 2-hydrooxy-2-methyl-1-phenylpropan-1-one and the like. When UV rays are emitted through a transparent resin film comprising a UV ray absorber, a radical photopolymerization initiator having an absorption range within the visible wavelength range is used. Examples of such initiators are bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2,4,6- Trimethylbenzoyldiphenylpispine oxide and the like.

When the mold is in the form of a flat plane with a plated surface with fine nonuniformities on the surface, the non-uniform surface of the mold is a layer of transparent resin film with an uncured ionized radiation curable resin coated on a layer of transparent resin film. And a coated layer of ionizing radiation curable resin weakly adhered to the non-uniform surface of the mold, and then ionizing radiation is emitted from the side of the transparent resin film to cure the ionizing radiation curable resin. Thereafter, the cured layer of ionizing radiation curable resin is removed from the mold along with the transparent resin substrate film. Thereby, the non-uniform shape of the mold is transferred to the cured layer of ionizing radiation curable resin contained on the transparent resin film.

When the mold is in the form of a roll with a plated surface with fine non-uniformities on the peripheral surface and the non-uniform shape of the mold is transferred to the ionizing radiation curable resin, the ionizing radiation curable resin is transferred to the peripheral surface of the roll-shaped mold. During contact, the stack of layers of ionizing radiation curable resin is radiated with ionizing radiation and then the ionizing radiation curable resin is removed from the mold along with the transparent resin film. Thereby, the non-uniform shape of the mold is continuously transferred to the cured layer of ionizing radiation curable resin contained on the transparent resin film.

The ionizing radiation may be UV rays or electron beams. In view of ease of handling and safety, UV rays are preferably used. As the UV light source, preferably a high pressure mercury lamp, a metal halogen lamp or the like is used. When the radiation is carried out through a transparent resin film containing a UV absorber, preferably a metal halogen lamp is used which contains a large amount of visible light components. Also, preferably "V-Bulb" and "D-Bulb" (both trade names) (usable by Fusion UV system JAPAN KK) can be used. The dose of ionizing radiation is sufficient to harden the UV curable resin at the stage where the cured film can be removed from the mold. In order to improve the surface strength, the cured layer of ionized radiation curable resin and the stack of transparent resin layer may be further spun on the side of the layer of ionizing radiation curable resin.

According to the above-described method, an antiglare layer (antiglare) having a haze of 5% or less can be prepared. Haze is defined by JIS K 7136 (expressed as diffused transmittance / total light transmittance) x 100 (%).

As described above, a mold with fine nonuniformities that do not have substantially any flat top view is used and the shape of such nonuniforms may be transferred to a transparent resin film or a cured layer of ionized radiation curable resin laminated on the transparent resin film. At that time, the anti-glare surface of the transparent resin film has fine non-uniformities having substantially no flat top view.

The anti-glare layer 30 formed by the above-described method is on one surface of the above-mentioned linear polarizer 20 having a surface (anti-glare surface) subjected to outward-facing antiglare, that is, on an anti-glare surface that does not face the linear polarizer 20. On the other hand, the first retardation plate and / or the second retardation plate are laminated on the other surface of the linear polarizer 20. Thereby, the anti-glare polarizing film layered 40 shown in FIG. 2 and FIG. 3 is formed. In order to laminate the layer or plate, an adhesive with good transparency, such as an acrylic adhesive, is preferably used.

Examples

In the present specification, the invention will be illustrated by the following examples, which do not limit the scope of the invention in any way.

Example 1

(a) Preparation of the mold

The peripheral surface of the aluminum roll having diameter 300 mm (5056 according to JIS) was mirror polished. The mirror polished peripheral surface of the aluminum roll was then subjected to a blasting pressure (gauge pressure, bone) of 0.1 MPa using a blasting apparatus (purchased from FUJI Manufacturing Co., Ltd) to form non-uniformities on the surface. Blast with zirconia beads “TZ-SX-17” (trade name, available by TOSO CORPORATION; average particle size: 20 μm) under the same specification. Aluminum rolls with surface irregularities are electroless polished plated with nickel to form a metal mold. Plating conditions were set to form a nickel layer having a thickness of 12 mu m. After plating, the thickness of the nickel layer was measured with a beta-wire film thickness meter (“Fisher Scope MMS” available by Fischer Instruments KK) and was 12.3 μm.

(b) Preparation and Evaluation of Antiglare

The photocurable resin composition "GRANDIC 806T" (trade name, available by Dainippon Ink & Chemicals Inc.) was dissolved in ethyl acetate to obtain a 50% concentration solution. Thereafter, in the solution, the photopolymerization initiator "LUCILIN TPO" (trade name, available by BASF; chemical name: 2,4,6-trimethylbenzoyldiphenylphosphine oxide) was prepared in order to obtain a coating structure. It was added in the amount of 5 parts by weight per part by weight. The coating tissue was coated on a triacetyl cellulose (TAC) film with a thickness of 80 μm so that the coating thickness after drying was 5 μm and then fixed at 60 ° C. in a dryer for 3 minutes. After drying, the TAC film was pressed with weak contact with the non-uniform surface of the metal mold prepared in (a) with a rubber roll so that the photo-curable resin tissue layer was in contact with the nickel plated surface of the mold. In such a state, light in a high pressure mercury lamp with an intensity of 20 mW / cm 2 was emitted from the side of the TAC film at a dose of 200 mJ / cm 2 with a h-ray converted light size to cure the photo-curable resin tissue. Thereafter, the TAC film with the cured resin layer was removed from the mold to obtain a transparent antiglare film composed of a stack of a cured resin layer with surface nonuniformities and a TAC film.

The haze of the antiglare film was measured using a haze meter "HM-150" (available by the Murakami Color Research Laboratory) in accordance with JIS K 7136, and was 0.9%. For the measurement, a sample of the antiglare film was attached with an optically transparent adhesive to a glass plate with a non-uniform surface facing outward to prevent warpage.

The transmittance resolution was measured using an image clarity meter "ICM-1DP" (available by Suga Test Instruments Co., Ltd.) in accordance with JIS K 7105. For the measurement, a sample of the antiglare film is attached with an optically clear adhesive to a glass plate having an outwardly non-uniform surface to prevent warpage. The sample was then irradiated with light from the back side (the surface in contact with the glass plate), and the transmittance resolution was measured. The result is as follows.

It was measured using the same filamentometer "ICM-1DP" used for the above measurement of transmittance resolution. For the measurement, a sample of the antiglare film was attached with an optically transparent adhesive to a glass plate with a non-uniform surface facing outward to prevent warpage. In order to suppress reflection on the back glass surface, a black acrylic resin plate with a thickness of 2 mm was fixed with water on the exposed surface of the glass plate with the antiglare film. In this state, the measurement was performed by emitting light from the side of the sample of the antiglare film. The result is as follows.

*: Excluded from the sum of the values of the reflection resolution.

The reflectance measures the change of reflectance in the plane including the vertical and radial directions of the film and the radiation of the non-uniform surface of the glare film with the collimated beam from the He-Ne laser in a direction tilted at the film's vertical line by 30 degrees. It was measured by Reflectance was measured using a "3292 03 optical power sensor" and a "3292 optical power meter" (both available by Yokogawa Electric Corporation). As a result, R (3) was 0.374%, R (40) was 0.00064%, and R (60) / R (30) was 0.00010.

Using a confocal microscope "PLu 2300" (available by Sensofar Corporation), the surface shape of the antiglare film was observed. For observation, a sample of the antiglare film was attached with an optically transparent adhesive to a glass plate having an outwardly nonuniform surface to prevent warpage. The magnification of the objective lens is 50 times. The obtained data was processed according to the algorithm described above and the average area of the Voronoi polygons was calculated to be 582 μm ² . From the three-dimensional coordinate information, it was confirmed that the entire surface of the antiglare had fine nonuniformities, but no flat portion.

The conditions for the manufacture of the mold, and the optical properties and surface conditions (average area of the Voronoi polygons) of the antiglare film are summarized in Table 1.

Based on the three-dimensional coordinates obtained from the above observation of the surface shape, the number of vertices of the convex portions in the 200 μm × 200 μm field, the arithmetic mean height Pa and the maximum cross-sectional height Pt of the cross-sectional curve, and the peak position of the histogram of the heights are Was calculated. The results are shown in Table 2.

(c) Preparation of Anti-glare Polarizing Film Lamination

The following polarizing plate and retardation plate were provided.

Polarizer: Polyvinyl alcohol iodine linear polarizer with a protective film made of triacetyl cellulose on both surfaces (available by SUMIKARAN SRH 842A (trade name) Sumitomo Chemical Co., Ltd.).

n_z).Shortening the delay plate stretching: stretching in the speed of the cyclic polyolefin resin with a R ₀ and R _th of 50 nm of 100 nm film (ARTON (trade name) available by _{JSR Corporation) (n x> n} y

n _z ).

n_y > n_z).Biaxially stretched retarder: biaxially stretched membrane of cyclic polyolefin resin with 0 nm R ₀ and 110 nm R _th (available by ARTON® JSR Corporation) (n _x

n _y > n _z ).

The polarizing plate (SUMIKARAN SRH 842A) and the shortened stretching plate were attached with an adhesive such that the transmission axis and the phase retardation axis of the polarizing plate were parallel to each other. On the polarizing plate, the antiglare film prepared in (b) was attached to the nonuniform surface facing outward to obtain the antiglare polarizing film stack. Individually, the polarizing plate (SUMIKARAN SRH 842A) and the biaxially stretched retardation plate were attached with an adhesive to obtain a polarizing film stack having no antiglare layer.

(d) Preparation and Evaluation of Liquid Crystal Displays

The polarizers were separated from the back and display surface of a commercially available monitor with a VA mode liquid crystal display device for a personal computer. Then, instead of the first polarizing plates used, the antiglare polarizing film layer prepared in (c) is attached to the display surface side with an adhesive, so that the retardation film drawn in a single axis faces the display surface side and the transmission axis of the antiglare polarizing film layer is The polarizing film layered in the direction of the transmission axis of the most polarizing plate and not having any antiglare layer prepared in (c) is attached to the back side with an adhesive, so that the retardation plate biaxially stretched toward the back side and the transmission of the polarizing film layered The axis was aligned with the transmission axis of the original polarizer. As a result, a liquid crystal display having an antiglare layer was assembled.

The personal computer was activated in the dark room, and the brightness of the liquid crystal display in the black display state or the white display state was measured using the luminance meter "BM5A" (available by TOPCON Corporation) and then the contrast was calculated. Here, the contrast is expressed as the ratio of the luminance in the white display state to the luminance in the black display state. As a result, the contrast of the liquid crystal measured in the dark room was 909.

The evaluation system was then moved to a bright space and the reflection of the display in the dark display state was visually observed. As a result, virtually no reflection was observed. This confirms that the liquid crystal display has good antiglare characteristics. The results are summarized in Table 3.

Examples 2 and 3

Metal molds with non-uniform surfaces were prepared in the same manner as in Example 1 except that the thickness of the plated nickel layer was changed as shown in Table 1. Using the metal mold thus prepared, a transparent antiglare film and a TAC film composed of a cured resin layer having nonuniformities on its surface were produced in the same manner as in Example 1. The optical properties and surface state of the antiglare film (average area of the Voronoi polygons) are summarized in Table 1. With each film, the number of vertices of convex parts in the field of 200 μm × 200 μm, the arithmetic height Pa of the cross-sectional curve and the maximum cross-sectional height Pt, the peak positions of the histogram of the heights were calculated in the same manner as in Example 1 . The results are shown in Table 2. In addition, a liquid crystal display having an antiglare layer was assembled using these films in the same manner as in Example 1, and the contrast and antiglare characteristics were evaluated. The results are shown in Table 3.

Comparative Example 1-5

For comparison, the glare films “AG1”, “AG3, each used as a polarizer“ SUMIKARAN ”(available by Sumitomo Chemical Co., Ltd.) and comprising a filler dispersed in a UV curable resin. "," AG5 "," AG6 "and" AG8 "were used and the optical properties and the average area of the Voronoi polygons of these antiglare were recorded in Table 1 together with the results of Examples 1, 2 and 3. With such films, when using the measured three-dimensional coordinates when calculating the average area of the Voronoi polygons, the number of vertices of convex parts in the field of 200 μm × 200 μm, the arithmetic height Pa of the cross-sectional curve and the maximum cross-sectional height Pt The peak positions of the histogram of, and altitudes were calculated in the same manner as in Example 1. The results are reported in Table 2 with the results of Examples 1, 2 and 3. In addition, a liquid crystal display having an antiglare layer was assembled using an antiglare film in the same manner as in Example 1, and contrast and antiglare characteristics were evaluated. The results are shown in Table 3 together with the results of Examples 1, 2 and 3.

As can be seen from the results shown in Tables 1 and 3, the samples of Examples 1, 2 and 3 which have reached the resolution, reflection profile and surface shape of the haze according to the invention show excellent anti-glare properties (without reflection) , Achieving high contrast and good visibility. In addition, the samples result in less glare and less whitening.

The samples of Comparative Examples 1 and 2 do not experience whitening because R (30) is 2% or less, R (40) is 0.003% or less and R (60) / R (30) is 0.001 or less. However, when the average area of the Voronoi polygons of these samples exceeded 1,500 μm ² , they resulted in glare. When the liquid crystal display was assembled using anti-glare polarizing film stacks prepared from the anti-glare films of the comparative examples, the contrast in Comparative Examples 1 and 2 was very high and 896 and 890 respectively, but the anti-glare properties were not satisfactory, and Table 3 As shown in, visibility was low. When having the samples of Comparative Examples 3, 4 and 5, R (40) exceeded 0.003% and R (60) / R (30) exceeded 0.001. Thus, they whitened more than the samples according to the invention. In Comparative Examples 3, 4 and 5, the haze was high and therefore the contrast tends to be reduced.

The liquid crystal display of the present invention has good antiglare properties and also achieves high contrast and thus is excellent in terms of visibility and brightness of the displayed image. The antiglare polarizing film stack of the present invention has fine nonuniformities on the surface but low haze in order to achieve antiglare properties. Therefore, the anti-glare polarizing film stack of the present invention can achieve a high contrast ratio when applied to a liquid crystal display, in particular, a VA mode liquid crystal display.

Claims (11)

A liquid crystal cell comprising a pair of cell substrates and a liquid crystal layer sandwiched between the cell substrates and the liquid crystal molecules oriented in a direction substantially perpendicular to the substrate in the vicinity of the substrate to which no voltage is applied; A pair of linear polarizers located on the outer surfaces of each of said cell substrates sandwiching a liquid crystal cell in between; As the cell substrate of the first retardation plate is located between one and each of the linear polarizer of the first retardation plate having a refractive index satisfying a relationship of n _x> n _y ≥ n _z, of the first retardation plate The phase retardation axis is positioned such that it is substantially parallel or substantially perpendicular to the transmission axis of the adjacent linear polarizer, where n _x and n _y are main refractive indices in the film plane and n _z is the refractive index in the thickness direction of the film. The first retardation plate; The second retardation plate positioned between the first retardation plate and the cell substrate or between the other cell substrate and the linear polarizer opposite thereto, wherein the second retardation plate is n _×

said second retardation plate having refractive indices satisfying a relationship of n _y > n _z , wherein n _x , n _y and n _z are the same as defined above; And An antiglare layer located on the surface of one of the linear polarizers opposite the surface opposite the liquid crystal cell, wherein the antiglare layer has a haze of 5% or less with respect to normal incident light, and 0.5 mm, 1.0, respectively. When measured at an angle of incidence of 45 degrees of light using three optical frequency combs consisting of dark and bright lines with widths of mm and 2.0 mm, a total reflection resolution of less than 50% and 2% for incident light entering an angle of incidence of 30 degrees Reflectance R (30) at a reflection angle of 30 degrees or less, reflectance R (40) at a reflection angle of 40 degrees of 0.003% or less with respect to incident light entering at an angle of incidence of 30 degrees, and R (≥60) incident light entering an angle of incidence of 30 degrees Has a ratio of R (≥60) to R (30) of 0.001 or less when the reflectance in any direction at a reflection angle of 60 degrees or more with respect to the surface of the antiglare layer is 50 µm ² to A polygon having an average area of 1,500 μm ² , the polygon comprising an antiglare layer formed by voronoi segmentation of a surface using vertices of convex portions of the surface nonuniformities as a parent point; . The method of claim 1, And the second retardation plate is located between the cell substrate opposite the first retardation plate and the linear polarizer opposite the cell substrate. The method of claim 1, And the second retardation plate is located between the first retardation plate and the cell substrate. The method of claim 1, The polygons of the antiglare layer have an average area of 300 μm ² to 1,000 μm ² , and the polygons are formed by Voronoi division of the surface using the vertices of the convex portions of the surface nonuniformities as a parent point. , Liquid crystal display. As an anti-glare polarizing film laminated | stacked containing an anti-glare layer containing an anti-glare layer, a linear polarizer, and a retardation plate laminated in order, The antiglare layer was measured at an angle of incidence of 45 degrees of light using a haze of less than 5% of normal incident light and three optical frequency combs consisting of dark and bright lines with widths of 0.5 mm, 1.0 mm and 2.0 mm, respectively. At a total reflection resolution of 50% or less, a reflectance R (30) at a 30 degree reflection angle of 2% or less for incident light entering a 30 degree incidence angle, and a 40 degree of reflection angle of 0.003% or less for an incident light entering a 30 degree incident angle. The ratio of the reflectance R (40) and R (≥60) to R (30) which is less than 0.001 which is the reflectivity in any direction at a reflection angle of 60 degrees or more with respect to the incident light where R (≥60) enters the incident angle of 30 degrees. to have a surface of the anti-glare layer comprises a polygon having an average area of 50 ㎛ ² to 1,500 ㎛ ^2, wherein the polygon is of the convex portion of the surface non-uniform stained by generatrix Using the points formed by Voronoi partitioning of the surface; The delay plate is a first delay plate and n _x having refractive indices satisfying a relationship of n _x > n _y ≧ n _z .

at least one retardation plate selected from the group consisting of second retardation plates having refractive indices satisfying a relationship of n _y > n _z , wherein the phase retardation axis of the first retardation plate is used when the first retardation plate is used. N _x under the condition that it is positioned to be substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer. And n _y is a main refractive index in the film plane and n _z is a refractive index in the thickness direction of the film. The method of claim 5, The retardation plate consists of the single first retardation plate having a relationship of n _x > n _y ≥ n _z , wherein the phase retardation axis of the first retardation plate is substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer. Anti-glare polarizing film deposition. The method of claim 5, The delay plate is n _x

An antiglare polarizing film stack composed of the single second retardation plate having a relationship of n _y > n _z . The method of claim 5, The delay plate is the first delay plate and n _x having a relationship of n _x > n _y ≥ n _z .

an antiglare polarizing film stack composed of the second retardation plate having a relationship of n _y > n _z , and positioned such that the phase retardation axis of the first retardation plate is substantially parallel or substantially perpendicular to the transmission axis of the linear polarizer. . The method of claim 5, The polygons of the antiglare polarizing film stack have an average area of 300 μm ² to 1,000 μm ² , and the polygons are formed by Voronoi segmentation of the surface using the vertices of the convex portions of the surface nonuniformities as parent points. Anti-glare polarizing film laminated which is formed. The method of claim 5, The anti-glare layer is composed of a resin film having fine non-uniformities on the surface, the surface colliding fine particles to form non-uniforms on the polished metal plate, the non-uniformity of the metal plate to form a mold And electroless nickel plating on one surface, moving the surface nonuniformities of the mold to the surface of the transparent resin film, and removing the resin film from the mold. The method of claim 5, The transparent resin film, UV curable resin or thermoplastic resin, anti-glare polarizing film laminated.

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