JPH02171703A - Manufacture of color filter - Google Patents

Abstract

PURPOSE:To easily flatten the printed surface of a color filter layer with high accuracy by bringing a color filter to printing formation on a prescribed filter substrate in accordance with a size of a picture element, and thereafter, pressing a printed picture of the color filter, while bringing it to scanning by one to several lines easy by using a roller of a small diameter. CONSTITUTION:A roller 7 is moved (scanned) in the stripe direction of color filter layers 2R, 2G and 2B which are brought to printing formation in a stripe shape, the color filter layers 2R, 2G and 2B of one to several lines are pressed as one unit, and the surface of its printed surface is flattened (smoothened). Thereafter, a scan position by the roller 7 is shifted by a prescribed pitch in the direction being orthogonal to the stripe direction, and in its shift position, by moving the roller 7 in the same way, the color filter layers 2R, 2G and 2B of one to several lines are pressed, and the surface of its printed surface is flattened (smoothened). In such a way, irrespective of a screen size, a color filter in which the surface of the color filter layer is flattened extending over the whole area can be manufactured easily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a color filter incorporated into a large-sized liquid crystal display element.

[Prior Art] In recent years, liquid crystal display elements (LCDs) have become more dense, color displays have been made more sophisticated, and their display screens have become larger. However, liquid crystal display elements have evolved from conventional segment display to dot matrix display, and in recent years, display screen configurations have been made by miniaturizing display pixel size and arranging many pixels in two-dimensional (planar) arrays with minute array pitches. It has even reached the point where it can be used to display color TV images.

However, the reality is that liquid crystal display elements for displaying color TV images are still in practical use only with a screen size of about 2.5 to 4 inches from the viewpoint of display image quality. A major problem remains as to how to increase the display screen size.

By the way, when realizing a color display type liquid crystal display element,
A color filter corresponding to each display pixel, for example, R
Individual color filters corresponding to the pixel sizes representing the three primary colors of (red), G (green), and B (blue) are used. This color filter is, for example, a predetermined glass substrate (
(Filter board)■ On the top, R, G,
B color filter layer 2+? , 2G, and 2I3 are printed and formed in correspondence with each pixel. These color filter layers 2R and 2G.

2B are provided in a matrix or in a stripe shape, for example, corresponding to the arrangement pitch of the pixels. Therefore, a color display type liquid crystal display element basically consists of color filter layers 2R, 2G, and 2B printed on a glass substrate (filter substrate) as described above, and predetermined transparent electrodes 3 on the color filter. This transparent electrode 3 is paired with a glass substrate 5 on which a transparent electrode 4, which forms a matrix of pixels, is disposed facing each other with a predetermined gap therebetween, and a liquid crystal material is placed between them. This is realized by filling 6.

When a liquid crystal driving voltage is selectively applied between the transparent electrodes 3 and 4, the liquid crystal substance 6 in the area (pixel) specified by the transparent electrodes 3 and 4 to which this liquid crystal driving voltage is applied is oriented. A color filter layer H? in which light that changes depending on the orientation is provided corresponding to the above region (pixel). , 2G, 2B
Color display is performed by selectively viewing the screen.

[Problems to be Solved by the Invention] However, in such a liquid crystal display element, the color filter layer 2R printed on the filter substrate 1 as described above,
2G and 213, if there is a bulge peculiar to printing due to viscosity or the like in the printing ink, the gap between the transparent electrodes 3 and 4 changes as schematically shown in FIG. In other words, the parallelism between the transparent electrodes 3 and 4 will be impaired. Such nonparallelism between the transparent electrodes 3 and 4 significantly impairs the orientation of the liquid crystal substance 6 interposed therebetween, and becomes a major factor in deteriorating the quality of displayed images.

Therefore, in the past, a color filter layer 2R,
After printing and forming the color filter layers 2G and 2B, for example, by passing them through a roller, the printed surfaces are pressed to flatten (smooth) the upper surfaces (surfaces) of the color filter layers 2R, 20, and 2B. . However, as the screens of liquid crystal display devices become larger, the size of the color filters incorporated therein also tends to become larger. , 2G, 2B
It has become extremely difficult to uniformly press the upper surface (surface) of the printer to flatten (smooth) the printed surface. It has also become difficult to control the force of the breath.

The present invention has been made in consideration of these circumstances, and its purpose is to print the printed surface of a color filter layer printed on a predetermined filter substrate, regardless of the size of the display screen. Easy and accurate flattening (smoothing)
An object of the present invention is to provide a method for manufacturing a color filter that can perform the following steps.

[Means for Solving the Problems] A method for manufacturing a color filter according to the present invention includes disposing color filters corresponding to each pixel of a large screen in which a plurality of pixels are arranged in a matrix on a predetermined filter substrate. After forming a print corresponding to the size of the pixel, the printed surface of the color filter is pressed while scanning one to several lines at a time using a small diameter roller to flatten the printed surface of the color filter. It is characterized by the following.

[Function] According to the present invention, the printed surface of a color filter printed on a predetermined filter substrate is pressed while scanning one to several lines at a time using a small diameter roller, so it can be easily pressed with a small pressing force. Furthermore, it becomes possible to sequentially flatten (smooth) the printed surface of the color filter with high precision. Moreover, while controlling the pressing force locally,
The printed surface of the color filter can be flattened (smoothed) with high accuracy. As a result, the printing surface of the color filter can be accurately flattened (
It becomes possible to easily obtain a smoothed color filter.

[Example] Hereinafter, a method for manufacturing a color filter according to an example of the present invention will be described with reference to the drawings.

The method for manufacturing a color filter according to the present invention is basically: Prior to the first step of printing and forming color filters corresponding to the size of the pixels on the (glass substrate) and the step of drying and solidifying the color filters printed on this filter substrate, the printed surface of the color filters is pressed. The second step is to flatten (smooth) the printed surface by this press treatment, and the third step is to dry and solidify the color filter whose printed surface has been flattened (smoothed) by this press treatment to complete the color filter. .

The first step uses R (red), G (green), and B (blue) printing inks, respectively, to form a red filter layer 2R.

It consists of a step of sequentially printing a green filter layer 2G and a blue filter layer 2B on a predetermined glass substrate (filter substrate) in a stripe shape, for example, at a predetermined pitch. This printing process is performed, for example, by shifting one printing plate at a predetermined pitch and repeating it three times with different printing ink colors.

Through this printing process, red, green, and blue color filter layers 2R, 2G, and 2B are printed and formed alternately in stripes on a predetermined glass substrate l at a predetermined pitch corresponding to the pixel arrangement.

However, each color filter layer 2) printed and formed in this way
? , 2G, and 2B are generally microscopically raised in the center due to the viscosity of the printing ink.
It has a so-called kamaboko-shaped printed cross-sectional shape, and there is a difference of about 2 to 4 mm in layer thickness between the center part and the edge part. And between the stripe-shaped filter layers 2R, 2G, and 28 of each color.
In many cases, about 11 grooves are formed.

In order to flatten (smooth) the printing surfaces of the color filter layers 2R, 2G, and 2B, a press treatment is performed in a second step.

In the pressing process in this second step, the present invention uses a roller 7 with a roller width corresponding to the pixel width of one to several lines and a small diameter that enables local pressing, as illustrated in FIG. 1, for example. A color filter layer 2R is printed and formed on the glass substrate l using the above-mentioned color filter layer 2R.

20 and 2B one to several lines at a time, for example, as shown in FIG. It is characterized by the fact that

Specifically, the roller 7 is moved (scanned) in the stripe direction A of the color filter layers 2R, 2G, 211 printed in a stripe shape to form one to several lines of the color filter layers 2R, 2G, 211. 213 is pressed as one unit, and the printed surface is flattened (smoothed).

After that, the scanning position by the roller 7 is shifted by a predetermined pitch in the direction B perpendicular to the striping direction A, and the roller 7 is similarly moved (scanned) at the shifted position to color one to several lines. Filter layer 2R, 2
G, 2B is pressed and the printed surface is flattened (smoothed).

Color filter layers 2R and 2G formed by such rollers 7.

Scanning and pressing of the printing surface of 2B is repeatedly performed to press the entire printing surface of each color filter layer 2R, 2G, and 2B, and the entire printing surface is flattened (smoothed).

At this time, optimization control of the pressing force by the roller 7 is performed in accordance with the scanning position as necessary. Further, the color filter layers 2R and 2G.

Regarding the alignment mark portion 8 which is printed and formed outside the screen area on the filter substrate l at the same time as the roller 7
Control of the scanning area, such as excluding it from the scanning/pressing target area, is performed.

After the printing surfaces of the color filter layers 2R, 2G, and 2B are flattened (smoothed) by the press treatment in the second step as described above, they are dried and solidified in the third step described above. It will be done.

According to this method of manufacturing a color filter, the color filter layer 2R is printed and formed on the glass substrate l using the narrow roller 7 with a small diameter.

Since the printed surfaces of 2G and 2B are locally pressed while scanning, multiple color filter layers 2R,
Even if the print formation areas of 2G and 2B form a large screen, the color filter layer 2R covers the entire area.

Effectively flatten (smooth) the printed surface of 2G and 2B.
can do.

By the way, in the conventional case, color filter layers 2R and 2G are used.

Because we prepared rollers corresponding to the printing width of 2B and performed the press process all at once, it was extremely difficult to ensure parallelism between the press surface of the rollers and the filter substrate over the entire area. There were problems such as difficulty in uniformly controlling the pressing force over the entire area. In this regard, according to the present invention, there is no need to prepare a roller corresponding to the printing width of the color filter layers 2R, 2G, and 2B each time, and the above-mentioned problem of parallelism does not occur.
Color filter layer 2, although the pressing process takes some time.
R.

It becomes possible to effectively flatten (smooth) the printing surface over the entire area of the 2G and 2B printing areas. Furthermore, even if the size of the area where the color filter layers 2R, 2G, and 2B are printed changes, the roller 7 is adjusted accordingly.
All you need to do is change the scanning area by
It is possible to effectively deal with color filters corresponding to screens of various sizes.

Moreover, as mentioned above, since the diameter of the roller rough is small, the color filter layer 2R can be formed sufficiently effectively with a small pressing force.

Since the printed surfaces of the color filter layers 2G and 213 can be pressed, the flattening (smoothing) efficiency is very high, and the printed surfaces of the color filter layers 2R, 2G, and 2B can be flattened (smoothed) simply and easily. There are advantages such as being able to

Note that the present invention is not limited to the embodiments described above. Here, a plurality of color filter layers 2R and 2G.

Although an example in which the color filter layers 2B are formed in a stripe shape has been shown, the present invention can be similarly applied to a case in which the color filter layers 2R, 2G, and 2B are formed in a lattice shape. Also, color filter layer 2
The width and diameter of the roller 7 that presses the R, 20, and 2B printing surfaces may be determined according to the pixel size, its pressing (flattening) specifications, etc. Furthermore, it is also possible to prepare a plurality of rollers 7 and drive them in parallel to improve the press processing efficiency. In addition, the present invention can be implemented with various modifications without departing from the gist thereof.

[Effects of the Invention] As explained above, according to the present invention, the printed surface of the color filter, which is printed on a predetermined filter substrate in correspondence with the pixels of the display screen, is printed one to several times using a small diameter roller. Since it is flattened (smoothed) by pressing while scanning line by line, it is possible to easily produce a color filter in which the entire surface of the color filter layer is flattened, regardless of the screen size. When incorporated into a liquid crystal display element, the conventional problem of liquid crystal alignment can be effectively resolved, and other great practical effects can be achieved.

[Brief explanation of the drawing]

FIGS. 1 and 2 are diagrams showing the concept of press processing to explain a method of manufacturing a color filter according to an embodiment of the present invention, and FIG. 3 is a schematic diagram of a liquid crystal display element incorporating a color filter. FIG. ■...Glass substrate (filter substrate) 2R, 2G. 2B...Color filter layer (color filter formed by printing)
, 3.4... Transparent electrode of liquid crystal display element, 5... Glass substrate, 6... Liquid crystal substance, 7... Roller, 8...
Alignment mark. Applicant's agent Patent attorney Takehiko Suzue Figure 3

Claims (1)

[Claims] After printing and forming color filters corresponding to each pixel of a large screen in which a plurality of pixels are arranged in a matrix in accordance with the size of the pixels on a predetermined filter substrate, the printed surface of this color filter is 1 using a small diameter roller
A method for manufacturing a color filter, which comprises flattening the printed surface of the color filter by pressing while scanning one or several lines at a time.