JPH08202275A - Non-reflection polarizing plate and its production - Google Patents

Abstract

PURPOSE: To prevent the generation of moire fringes even if the above polarizing plate is used in combination with a display element in which reflective grating wiring parts exist by distributing and fixing particles to plural linear or curved shapes in such a manner that these particulates are non-paralleled with substrate wirings. CONSTITUTION: This non-reflection polarizing plate 1 dispersely fixed with the particulates on its front surface is formed by distributing the particulates of silica, alumina, etc., to the plural linear or curved line shapes in such a manner that these particulates are non-paralleled with the substrate wirings 21. As a result, the linearity of the distributions of the light scattering particles and light scattering micro-rugged parts of the non-reflection polarizing plate 1 is averted by the adequate straight lines or curved lines in such a manner these particles are non-paralleled with the substrate wirings 21, by which the light interference density is lowered and the moire fringes specific to the liquid crystal display element are eliminated. The particles are preferably distributed to be inclined by >=5 deg. with the directions of the wirings of the substrate wirings 21 in the case the plural linear particulates are distributed. The particulates are preferably distributed to an arc shape or S shape in the case the particulates are distributed to the plural curved line shapes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-reflective polarizing plate and its manufacturing method. More specifically, it relates to a non-reflective polarizing plate capable of preventing the generation of moire fringes and a method for producing the same.

[0002]

2. Description of the Related Art A polarizing plate often used in liquid crystal display devices has a structure in which, for example, a polarizing film is sandwiched between base films, and each outer surface is subjected to a scratch resistant film treatment or an adhesive film treatment. The polarizing plate is attached to a liquid crystal display device to be integrated and then used for display.

The required characteristics required for the polarizing plate include scratch resistance, solvent resistance, and heat resistance in addition to the basic polarization characteristics. In addition, recently, a polarizing plate is required to have a property that “light from a backlight is more easily transmitted and light from the outside is not reflected as much as possible”, and a polarizing plate subjected to antireflection treatment is desired. Came.

The antireflection treatment is carried out by applying an antireflection film on the surface of the polarizing plate, roughening the surface of the polarizing plate by sandblasting, or mixing light diffusing fine particles such as silica in the coating material. Is applied to the surface of the polarizing plate, but from the viewpoint of the light diffusion effect and the productivity, the method of applying the coating material containing fine particles is generally used.

As an example showing a conventional technique, a "fine particle coating method" in which light diffusing fine particles such as silica and alumina are mixed in a coating film and then coated will be described. "Particle coating method"
When the transfer material is transferred and printed using a roller or squeegee, the application material is pushed to both sides by the roller or squeegee when viewed from the application direction, so the light diffusing fine particles are applied in a linear distribution. To be done.

In a liquid crystal display panel such as wirings arranged on an electrode substrate and a black matrix arranged in a color filter substrate, a reflective grid wiring portion (hereinafter referred to as substrate wiring) is provided on the surface or inside thereof. Exists in. The scattered light from the reflective grid wiring and the scattered light from the fine particles distributed in a straight line interfere with each other to generate moire fringes, which reduces the visibility of the display and thus reduces the commercial value. there were.

FIG. 4 is a side view of a conventional method for applying fine particles. In FIG. 4, 11 is a polarizing plate, 12 is a conveying roller, and 13 is a coating material coating roller. Polarizing plate 1
1 is moved in the direction of the arrow while the polarizing plate 11 is sandwiched by the rollers 12 and 13 while rotating the roller, and continuous coating is performed. At this time, it is known by SEM photograph analysis and the like that the coating material is pushed in the moving direction of the polarizing plate, and as a result, the fine particles are distributed linearly in the moving direction of the polarizing plate.

FIG. 5 is a diagram for explaining that the scattered light from the substrate wiring interferes with the scattered light from the fine particles. In FIG. 5, 21 is the substrate wiring, 22 is the fine particles coated on the surface of the polarizing plate, 23 is the scattered light from the substrate wiring, and 24 is the scattered light from the fine particles. The scattered light from the substrate wirings that are close to each other and the scattered light from the fine particles interfere with each other. When the density is low, it does not appear as moire stripes to the human eye,
When the density is high and the ratio of interference light from other portions is large, it appears as moiré fringes to the human eye, and hinders the original display image.

When the fine particles are distributed in a plurality of straight lines and the directions of the plurality of straight lines and the wiring directions of the substrate wiring are aligned and parallel to each other, the optical interference density increases, resulting in moire fringes. .

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and does not cause moire fringes when used in combination with a display element having a reflective lattice wiring portion. An object is to provide a non-reflection polarizing plate.
Further, it is also an object to provide a manufacturing method capable of easily manufacturing the non-reflection polarizing plate.

[0011]

As one of the means for solving the problems, a method of increasing the film thickness of the fine particle coating film to reduce the exposed portion of the fine particles on the film surface can be considered.
By reducing the exposed portion in this way, the scattered light from the fine particles is reduced and the moire fringes are eliminated. However, since the amount of scattered light from the fine particles is reduced, the amount of reflected light from the surface of the polarizing plate is increased, and the target antireflection function is reduced.

A method for easily obtaining a polarizing plate in which moire fringes do not occur without deteriorating the antireflection function has been made possible by improving the method of coating fine particles. In the present invention, such a problem is solved by applying the particles in a non-parallel manner so that the particles are not distributed in the wiring direction of the substrate wiring when the particles are applied.

That is, the invention according to claim 1 is a non-reflection polarizing plate in which fine particles are dispersed and fixed on the surface thereof, and the fine particles are formed into a plurality of linear shapes so as not to be parallel to the substrate wiring. Alternatively, it is characterized by being distributed in a curved shape.

The invention according to claim 2 is characterized in that the fine particles are distributed in a plurality of straight lines.

The invention according to claim 3 is characterized in that the fine particles are distributed in a plurality of straight lines so as to be inclined at least 5 ° or more with respect to the wiring direction of the substrate wiring.

The invention according to claims 4 and 5 is a non-reflective polarizing plate in which fine particles are dispersed and fixed on the surface thereof, and the fine particles are not distributed in a plurality of straight lines but arc-shaped or It is characterized in that it is distributed in a plurality of curved shapes such as an S-shape, that is, so as to draw a plurality of curves.

The invention according to claim 6 is a method for producing a non-reflective polarizing plate, wherein fine particles are applied in a plurality of linear or curved shapes by using a roller or a squeegee so as to be non-parallel to the substrate wiring. It is a feature.

The invention according to claim 7 is the method for producing a non-reflective polarizing plate according to claim 1, wherein fine particles are formed in the plurality of straight lines or curved lines so as not to be parallel to the substrate wiring.
It is characterized by being sprayed by a spraying method.

The invention according to claim 8 is the method for producing a non-reflective polarizing plate according to claim 1, wherein fine particles are formed in the plurality of straight lines or curved lines so as not to be parallel to the substrate wiring.
Printing is performed by a laser printing method.

The present inventor has also found that moire fringes can be prevented even if concave or convex portions having a polygonal polygonal pyramid are provided on the surface of the polarizing plate.

According to a ninth aspect of the present invention, there is provided the non-reflective polarizing plate having a concave or convex portion of a mirror-surface polygonal pyramid on the surface, so that moire fringes due to interference with scattered light from substrate wiring are not generated. It is characterized in that a concave portion or a convex portion is provided.

The invention according to claim 10 is characterized in that the concave portion or the convex portion is formed by rolling a roller having a convex portion or a concave portion on a contact surface on the surface of the non-reflection polarizing plate. To do.

The invention according to claim 11 is characterized in that the concave portion or the convex portion is formed on the surface of the antireflection polarizing plate by a sandblast method.

[0024]

The action of the invention according to claim 1 is that the linearity of the distribution of the light-scattering particles and the light-scattering fine irregularities of the non-reflection polarizing plate is
The light interference density is lowered by avoiding a suitable straight line or curved line so as to make them non-parallel, and thereby the moire fringes peculiar to the liquid crystal display element can be eliminated.

According to the second aspect of the present invention, the linearity of the distribution of the light-scattering particles and the light-scattering fine irregularities of the non-reflecting polarizing plate is avoided by using an appropriate straight line so as to be non-parallel. By reducing the interference density, it is possible to eliminate moire fringes peculiar to liquid crystal display elements.

The operation of the invention according to claim 3 is that the appropriate straight line is distributed in a plurality of straight lines inclined by at least 5 ° or more with respect to the direction of the wiring of the substrate wiring, whereby the light scattering of the non-reflection polarizing plate is performed. The light interference density is lowered by avoiding the linearity of the distribution of the particles and the light-scattering minute irregularities, whereby the moire fringes peculiar to the liquid crystal display element can be eliminated.

The operation of the invention according to claims 4 and 5 is to reduce the optical interference density by avoiding the linearity of the distribution of the light scattering particles and the light scattering minute uneven portions of the non-reflecting polarizing plate with an appropriate curve. Therefore, it is possible to eliminate the moire fringes peculiar to the liquid crystal display element.

The operation of the invention according to claim 6 is that a roller or a squeegee is moved in a straight line or a curved line to disperse and coat fine particles in a plurality of straight lines or curved lines so that the distribution of the light scattering particles or the light scattering minute uneven portions can be improved. By avoiding the linearity with an appropriate straight line or curved line, the optical interference density is reduced, whereby a non-reflection polarizing plate capable of easily preventing the generation of moire fringes can be obtained.

The function of the invention according to claim 7 is to spread fine particles in a linear or curved shape by a spraying method so that the linearity of the distribution of the light scattering particles or the light scattering minute uneven portions becomes non-parallel. First, it is possible to reduce the optical interference density by avoiding with an appropriate straight line or curved line, whereby it is possible to obtain a non-reflection polarizing plate that can easily prevent the generation of moire fringes.

According to the eighth aspect of the present invention, the linearity of the distribution of the light-scattering particles or the light-scattering fine irregularities is made non-parallel by printing fine particles in a linear or curved shape by a laser printing method. As described above, the light interference density is reduced by avoiding with an appropriate straight line or curved line, whereby a non-reflection polarizing plate capable of easily preventing the generation of moire fringes can be obtained.

With the function of the ninth aspect of the present invention, it is possible to preferably prevent the generation of moire fringes by the concave portion of the mirror-surface polygonal pyramid provided on the surface of the polarizing plate.

According to the tenth aspect of the present invention, the moire fringes are preferably produced by the concave or convex portion formed by rolling the roller having the convex or concave portion on the contact surface on the surface of the non-reflecting polarizing plate. Can be prevented.

The operation of the invention according to claim 11 is that the concave portion or the convex portion formed by the sandblasting method
The generation of moire fringes can be preferably prevented.

[0034]

【Example】

[Example 1] FIG. 1 is a plan view of an example of a method for producing a non-reflection polarizing plate of the present invention. In FIG. 1, 1 is a polarizing plate and 2 is a coating material coating roller. The roller 2 is actuated like a wiper on an automobile windshield in a fan shape having an optimum radius to apply the coating material. Since the fine particles of silica, alumina, etc. in the coating material are fan-shaped along the trajectory of the roller, that is, distributed non-parallel to the substrate wiring, the scattered light from the fine particles interferes with the scattered light from the linearly arranged substrate wiring. Without, moire fringes do not occur. In addition,
The fine particles may be distributed so as to draw other curves such as an S shape other than the fan shape (arc) (FIG. 3A).
(B)).

As shown in FIG. 3 (c), the fine particles are moved so as not to be parallel to the board wiring, for example, while the roller is tilted at least 5 ° or more with respect to the wiring direction of the board wiring. Is distributed in a plurality of straight lines, the same effect as described above can be obtained, and moire fringes do not occur.

[Second Embodiment] A squeegee may be used instead of the roller in the first embodiment. In this case, the squeegee operates like the wiper,
Alternatively, for example, the roller is moved so as to be non-parallel to the board wiring while inclining at least 5 ° or more with respect to the wiring direction of the board wiring.

[Third Embodiment] Further, instead of the roller coating method in the first embodiment, fine particles may be scattered in a plurality of straight lines or curved lines so as to be non-parallel to the substrate wiring by a spraying method. The scattered light from the fine particles does not interfere with the scattered light from the linearly arranged substrate wiring, and moire fringes do not occur.

[Embodiment 4] Instead of the roller coating method in Embodiment 1, laser printing is used to disperse fine particles in a plurality of straight lines or curved lines so as not to be parallel to the substrate wiring. Also, the scattered light from the fine particles does not interfere with the scattered light from the linearly arranged substrate wiring, and moire fringes do not occur.

[Embodiment 5] FIG. 2 is a view showing a method similar to the conventional method, except that the roller is provided with a convex portion of a mirror surface polygonal pyramid and the polarizing plate is provided with a concave portion of a mirror surface polygonal pyramid. . Figure 2
In FIG. 1, 1 is a polarizing plate, 2 is a coating material applying roller having convex portions of a mirror surface polygonal pyramid, and 3 is a conveying roller. In this case, the distribution of the concave portions formed in the polarizing plate is adjusted so as to eliminate the optical interference with the linearly reflected light from the substrate.
As shown in (b), the rollers are operated so that the rollers can be distributed in an optimal curved shape such as an arc shape or an S shape.
In addition, when the convex portions are distributed on the polarizing plate, a roller provided with concave portions having a mirror surface polygonal pyramid may be used.

FIG. 3C shows an example of a distribution method using a linear distribution.

Further, the concave portion or the convex portion can be formed by rolling a roller having a convex surface and a concave portion on the contact surface on the surface of the antireflection polarizing plate or by a sand blast method.

As a conventional example similar to this embodiment, Japanese Patent Laid-Open No. 63-63
There is one disclosed in Japanese Patent Application Laid-Open No. 216001, but in the technique described in that publication, the phenomenon of occurrence of moire fringes due to linearly reflected light is not taken into consideration, and measures against moire fringes are not taken. This point is a fundamental difference from the present embodiment.

[0043]

As described above, the first and second aspects of the present invention are as follows.
The effects of the inventions of 3, 4, and 5 are to provide a bright and clear liquid crystal display device without causing moire fringes because it has high antireflection properties and eliminates interference with scattered light from substrate wiring. It is possible.

The effect of the invention according to claim 6 is that the roller or squeegee is moved in a straight line or a curved line to apply the fine particles in a plurality of straight lines or curved lines, and it is possible to easily prevent the generation of moire fringes. That is, a polarizing plate can be obtained.

The effect of the invention according to claim 7 is to obtain a non-reflective polarizing plate which can easily prevent the generation of moire fringes by simply dispersing fine particles in a plurality of straight lines or curved lines by a spraying method. It is possible.

The effect of the invention according to claim 8 is to obtain a non-reflective polarizing plate which can easily prevent the generation of moire fringes by printing fine particles in a plurality of straight lines or curved lines by a laser printing method. Is possible.

The effect of the invention according to claim 9 is that it is possible to preferably prevent the generation of moire fringes by the concave and convex portions of the mirror surface polygonal pyramid provided on the surface of the polarizing plate.

The effect of the invention according to claim 10 is that a roller having a contact surface provided with a convex portion or a concave portion is rolled on the surface of the anti-reflection polarizing plate to form a concave portion or a convex portion, and the moire fringes can be preferably applied. Can be prevented.

The effect of the invention according to claim 11 is that the concave portion or the convex portion formed by the sandblast method is
The generation of moire fringes can be preferably prevented.

[Brief description of drawings]

FIG. 1 is a plan explanatory view of an embodiment of the invention according to the claims.

FIG. 2 is a plan view of an embodiment of the invention according to the claims.

3 (a), (b) and (c) are claims 1, 2, and
It is a plane explanatory view of a fine particle distribution method by an example of an invention concerning 3, 4, 5, 6, 7, and 8. It is also an explanatory plan view showing a distribution method of the concave portions according to the embodiments of the invention according to claims 9, 10 and 11.

FIG. 4 is a side view showing a conventional method of applying fine particles.

FIG. 5 is an enlarged cross-sectional view in the vicinity of the surface of a polarizing plate showing light interference between substrate wiring and fine particles.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Polarizing plate, 2 Coating material coating roller, 3 Conveying roller, 11 Polarizing plate, 12 Conveying roller, 13 Fine particle coating roller, 21 Substrate wiring, 22 Fine particle, 23
Scattered light from substrate wiring, scattered light from 24 particles.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G02B 5/30 G02F 1/1335 510

Claims (11)

[Claims] 1. A non-reflective polarizing plate having fine particles dispersed and fixed on the surface thereof, wherein the fine particles are distributed in a plurality of straight lines or curved lines so as not to be parallel to the substrate wiring. Non-reflective polarizing plate characterized by. 2. The antireflection polarizing plate according to claim 1, wherein the fine particles are distributed in a plurality of straight lines. 3. The non-reflection polarizing plate according to claim 2, wherein the fine particles are distributed in a plurality of straight lines so as to be inclined at least 5 ° or more with respect to the wiring direction of the substrate wiring. 4. The antireflection polarizing plate according to claim 1, wherein the fine particles are distributed in a plurality of curved lines. 5. The curve is arcuate or S-shaped,
In each case, by arranging a plurality of each of the curves in parallel with each other in the same shape and appropriately selecting a pitch to be used, moire fringes are generated due to interference between scattered light from the fine particles and reflected light from the grating wiring. The non-reflection polarizing plate according to claim 4, wherein the non-reflection polarizing plates are arranged at a pitch that does not impair the non-reflection effect. 6. The method for producing a non-reflective polarizing plate according to claim 1, wherein fine particles are dispersed and applied in a plurality of straight lines or curved lines using a roller or a squeegee so as to be non-parallel to the substrate wiring. A method for producing a non-reflective polarizing plate, which is characterized in that 7. The method for producing a non-reflective polarizing plate according to claim 1, wherein fine particles are dispersed in the plurality of straight lines or curved lines by a spraying method so as not to be parallel to the substrate wiring. Manufacturing method of non-reflective polarizing plate. 8. The method for producing a non-reflective polarizing plate according to claim 1, wherein fine particles are printed on the plurality of straight lines or curved lines by a laser printing method so as not to be parallel to the substrate wiring. A method for producing a characteristic non-reflective polarizing plate. 9. A non-reflective polarizing plate comprising fine particles dispersed and fixed on the surface thereof, wherein moire fringes due to interference between scattered light from the fine particles and reflected light from the grating wiring are not generated. A non-reflective polarizing plate characterized in that a concave portion or a convex portion of a mirror surface polygonal pyramid is provided on the surface. 10. The antireflection polarizing plate according to claim 9, wherein the concave portion or the convex portion is formed by rolling a roller having a convex portion or a concave portion on a contact surface thereof onto the surface of the antireflection polarizing plate. 11. The antireflection polarizing plate according to claim 9, wherein the concave portion or the convex portion is formed on the surface of the antireflection polarizing plate by a sandblast method.