JP3058382B2 - Alignment film solution transfer plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer plate of an alignment film solution used for manufacturing a liquid crystal panel.

[0002]

2. Description of the Related Art Liquid crystal panels have been applied to word processors, liquid crystal televisions and the like, and have attracted great expectations as various display devices.

[0003] Further, in the flow of improving display quality, the density and the screen size have been increasing.

This liquid crystal panel has a structure in which a liquid crystal is sandwiched between two glass substrates. that time,
It is necessary to align the orientation of liquid crystal molecules between two glass substrates in a certain direction. For that purpose, an alignment film is formed on a substrate. Generally, a thin film of a polymer substance is used for the alignment film. As a method of forming the alignment film, there are a spin coating method, a roll coating method, a printing method, and the like. However, the printing method is generally used because it is industrially low cost. This printing method is a method applying flexo (resin letterpress) printing, in which a concave portion of a transfer plate is filled with an alignment film solution and transferred to a substrate. After that, the solvent is evaporated by heating to form a film. As a transfer plate used for this printing, a transfer plate having a circular convex portion on a lattice point was used.

[0005]

By the way, with the increase in the screen size of the liquid crystal panel, the uniform orientation of the liquid crystal within the panel surface has been increased.
It becomes more difficult than before. Therefore, the uniformity of the alignment film thickness and the uniformity of the alignment treatment are required more than ever. However, it has become difficult to obtain an alignment film having a large area and a uniform thickness in a transfer plate conventionally used. In particular, in a liquid crystal panel having a large area and a high pixel density, in addition to the unevenness of the film thickness over a wide area within the panel surface due to the unevenness of the wiring and the like, the liquid crystal panel has a small area within the pixel or between the pixels. In addition, it is very difficult to obtain a uniform alignment film thickness due to the non-uniform film thickness.

As a method of improving this, a method of applying an alignment film solution by a spin coating method can be considered, but this method has a problem that the alignment film solution is applied to unnecessary portions. Further, there is a problem that productivity is reduced as compared with the printing method.

The present invention provides an alignment film solution transfer plate capable of realizing a high quality liquid crystal panel by forming an alignment film having a uniform thickness in consideration of the problems of such a conventional method of forming an alignment film. The purpose is to:

[0008]

SUMMARY OF THE INVENTION The present invention is directed to an alignment film solution transfer plate used for transferring an alignment film solution in an arbitrary shape onto a substrate. In the above, there is an alignment film solution transfer plate in which the convex portions are missing.

In the present invention, the material constituting the transfer film for the alignment film solution is mainly composed of a resin.

[0010]

The unevenness of the liquid film transferred to the substrate can be reduced by arranging the convex portions of the alignment film solution transfer plate in a grid pattern and removing the convex portions at each grid intersection. .

The thickness unevenness existing immediately after the transfer is leveled to some extent during drying. Since the area is small, that is, the transfer plate of the present invention has a short period in the plane of uneven film thickness, so that leveling is efficiently performed. Due to these synergistic effects, the uniformity of the alignment film obtained after drying is improved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view of an alignment film solution transfer plate according to one embodiment of the present invention. Numeral 11 denotes an alignment film solution transfer plate, and numeral 12 denotes a convex portion thereof.

FIG. 2 is a schematic view showing an alignment film printing apparatus using the alignment film solution transfer plate of the present embodiment. 21 is a dispenser, 22 is an anilox roll, 23 is a doctor roll, 24 is a plate cylinder, 11 is an alignment film solution transfer plate of this embodiment, 25 is a stage, and 26 is a substrate.

FIG. 3 is a graph showing the measurement results of the thickness of the alignment film obtained according to this embodiment. Here, the length of one side of the grid was 45 μm, the height of the projections was 5 μm, and the transfer plate was made of a photosensitive resin (APR (Asahi Kasei)).

As shown in FIG. 1, the alignment film solution transfer plate 11 is provided with convex portions 12 arranged in a lattice pattern, and at each lattice intersection, the convex portion 12 is missing. Printing of an alignment film was performed using a plate.

To print an alignment film, an alignment film solution is put into a dispenser 21 and a rotating anilox roll 22 is rotated.
The liquid film of the alignment film solution on the anilox roll 22 was uniformly spread by a doctor roll 23 rotating at the same speed as the anilox roll 22. Further, the substrate 2 was set on the stage 25 with the alignment film solution transfer plate 11.
No. 6 was transferred. FIG. 3 shows the result of measuring the thickness of the alignment film after the heating and drying.

As described above, an alignment film having a uniform thickness was obtained by using an alignment film solution transfer plate having projections 12 in a lattice shape and missing at the grid intersections.

Comparative Example FIG. 4 is a front view of an alignment film solution transfer plate used for a comparative example. Reference numeral 41 denotes an alignment film solution transfer plate, and reference numeral 42 denotes a convex portion thereof.

As shown in FIG. 4, an alignment film solution transfer plate 41 made of a resin in which circular convex portions 42 are arranged in lattice points was used to print the alignment film. .

The printing of the alignment film by the alignment film printing apparatus is performed by aligning the alignment film solution transfer plate 11 with the alignment film solution transfer plate 41 shown in FIG.
The procedure was performed in the same manner as in Example 1, except for changing to. After heating and drying, the results of measuring the thickness of the alignment film are shown in FIG.

As is apparent from FIG. 5, when the alignment film solution transfer plate having the circular convex portions 42 on the lattice points was used, the thickness of the alignment film varied.

As can be seen from the comparison between the present embodiment and the comparative example, it can be seen that the present invention has less variation of the alignment film and can obtain a uniform alignment film.

The lattice shape of the present invention is not limited to a square shape as shown in FIG. 1, but may be other shapes such as a rhombus or a parallelogram.

[0025]

As is apparent from the above description,
The present invention arranges the convex portions of the alignment film solution transfer plate in a lattice shape,
By missing at each lattice intersection, the thickness unevenness of the liquid film transferred to the substrate can be reduced,
By using the alignment film having a uniform thickness obtained in this manner, a liquid crystal display element with high display quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view schematically showing an embodiment of an alignment film solution transfer plate of the present invention.

FIG. 2 is a schematic view showing an alignment film printing apparatus used in the above-mentioned Examples and Comparative Examples of the present invention.

FIG. 3 is a graph showing a measurement result of a film thickness of an alignment film obtained according to the example of the present invention.

FIG. 4 is a front view schematically showing an alignment film solution transfer plate used in a comparative example.

FIG. 5 is a graph showing a measurement result of a film thickness of an alignment film obtained in a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Alignment film solution transfer plate 12 Convex part 21 Dispenser 22 Anilox roll 23 Doctor roll 24 Plate cylinder 25 Stage 26 Substrate 41 Alignment film solution transfer plate 42 Convex part

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41F 17/14 G02F 1/1337

Claims (2)

(57) [Claims] 1. An alignment film solution transfer plate used for transferring an alignment film solution onto a substrate in an arbitrary shape has convex portions formed in a lattice shape, and the convex portions are missing at each grid intersection. An alignment film solution transfer plate, characterized in that: 2. The alignment film solution transfer plate according to claim 1, wherein the material constituting the alignment film solution transfer plate contains a resin as a main component.