JPH0990114A - Formation of color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for formation of color filters with a decreased number of stages by eliminating the need for formation of color resists which are heretofore required to be applied over the entire part on a substrate and are exposed and developed every time the color filters of one color are formed on a substrate in the conventional method for forming the color filters of plural colors by photolithography. SOLUTION: A dyeable filter base material 3 is applied on the substrate and dyes of respective colors are applied dividedly by each color on the prescribed regions of this color filter base material 3 by using the hard masks 4a corresponding to each of the respective colors to dye these regions, by which the color filters of the plural colors are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming color filters of a plurality of colors on a substrate for a liquid crystal display device displaying a color image.

[0002]

2. Description of the Related Art For example, in a liquid crystal display device displaying a multicolor image, a black mask is formed on one transparent substrate (glass plate) of the liquid crystal display device, and a red mask is formed in an area inside the black mask. , Green and blue color filters are formed alternately in sequence.

Conventionally, each color filter of each color is formed by photolithography. Explaining the steps in the case of this photolithography, first, a photocurable first color resist, for example, a red color resist is uniformly applied over the entire area of the substrate on which the black mask is formed.

Next, a predetermined region of the resist film formed on the substrate is exposed using a photomask and developed to form a first color red color filter. Next, a second-color green color resist, for example, is applied onto the substrate, and the resist film is exposed and developed in the same manner as described above to form a second-color green color filter.

Next, a third color blue color resist is applied on the substrate, and the resist film is exposed and developed in the same manner as described above to form a third color blue color filter.

[0006]

As described above, when a color filter of a plurality of colors is formed by photolithography, a color resist is formed on the entire surface of the substrate each time a color filter of one color is formed on the substrate. The color resist must be applied, exposed and developed, which increases the number of steps and reduces efficiency.

The present invention has been made by paying attention to such a point, and an object of the present invention is to provide a method for forming a color filter capable of efficiently forming a plurality of color filters by reducing the number of steps. To provide.

[0008]

In order to achieve such an object, the present invention provides a method for forming a color filter of a plurality of colors on a substrate by a dyeing method, as the invention according to claim 1. A hard mask for each color that is unique to each color of multiple colors and that corresponds to the arrangement of color filters for each color is prepared, and a dyeable filter substrate is applied on the substrate to form a filter substrate film. , For each color, a corresponding hard mask is placed on the filter substrate film, and a dye of each corresponding color is applied on the filter substrate film through the hard mask, By dyeing the filter base material film in each color, a plurality of color filters are formed on the substrate in a predetermined arrangement.

According to a second aspect of the present invention, there is provided a method of forming color filters of a plurality of colors on a substrate by using a filter material in which pigments of the respective colors are dispersed and mixed, each color of the plurality of colors being unique. In, the openings are formed corresponding to the arrangement of the color filters of each color, prepare a plurality of hard masks for each color, for each color, place the corresponding hard mask on the substrate, through this hard mask The corresponding filter material is applied onto the substrate and the applied filter material is cured to form color filters of a plurality of colors on the substrate in a predetermined arrangement.

As an invention according to claim 3, an electrode is formed on substantially the entire area of the substrate according to claim 2,
The hard mask for each color is placed on this electrode, and a voltage is applied to the electrode when the filter material is applied to adjust the applied film thickness of the filter material.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 and FIG. 2 sequentially show steps of forming a color filter according to the first embodiment of the present invention. This process will be described with reference to FIG.
As shown in (A), a transparent substrate 1 made of glass or the like is horizontally arranged. A black mask 2 made of a metal film such as chromium is formed on the surface of the substrate 1.

Next, as shown in FIG. 1 (B), a dyeable filter substrate 3 made of casein, gelatin or the like is uniformly applied over almost the entire area of the substrate 1. Next, FIG. 1 (C)
As shown in FIG. 3, a first hard mask 4 a having a predetermined pattern is arranged on the filter substrate 3. Then, the first roller 5a as a dyeing means is arranged on the hard mask 4a. A first color, for example, red dye is applied to the peripheral surface of the roller 5a.

The roller 5a is replaced with the hard mask 4a.
And make it move in one direction while rotating. Along with this, the dye adhering to the roller 5a becomes hard mask 4
It is applied to a predetermined area of the filter substrate 3 through each opening 4a 'formed in a, and the predetermined area is dyed red to form a red color filter RF.

Next, the hard mask 4a and the roller 5a are removed from the filter base material 3, and a second hard mask 4b is placed on the filter base material 3 as shown in FIG. 2 (D). In addition, the second roller 5b is arranged on the hard mask 4b. A second color, for example, green dye is applied to the peripheral surface of the roller 5b.

The roller 5b is replaced with the hard mask 4b.
And make it move in one direction while rotating. Along with this, the dye adhering to the roller 5b becomes hard mask 4
It is applied to a predetermined area of the filter base material 3 through each opening 4b 'formed in b, and the predetermined area is dyed green to form a green color filter GF.

Next, the hard mask 4b and the roller 5b are removed from the filter base material 3, and a third hard mask 4c is placed on the filter base material 3 as shown in FIG. 2 (E). Further, the third roller 5c is arranged on the hard mask 4c. A third color blue dye is applied to the peripheral surface of the roller 5c.

The roller 5c is replaced with the hard mask 4c.
And make it move in one direction while rotating. Along with this, the dye adhering to the roller 5c becomes hard mask 4
It is applied to a predetermined area of the filter substrate 3 through the opening 4c 'of c, and the predetermined area is dyed blue to form a blue color filter BF.

Through these steps, as shown in FIG. 2 (F), red is formed on each area inside the black mask 2.
Green and blue color filters RF, GF, and BF are alternately formed.

According to this process, the filter base material 3 is applied on the substrate 1, and the hard masks 4a, 4b, 4c and the rollers 5a, 5b, 5c for each color are applied on the filter base material 3. The color filters RF, GF, and BF of the respective colors can be formed only by arranging them.

According to the conventional photolithography method, when forming the red, green and blue color filters,
Each time, apply color resist of each color on the substrate,
Although the color resist must be exposed and developed, in the present invention, the filter substrate 3 is provided on the substrate 1.
Is applied to the filter substrate 3, and hard masks 4a, 4b, 4c and rollers 5a, 5b, 5 corresponding to the respective colors are applied.
c are sequentially arranged so that color filters RF, GF, and
BF can be formed.

That is, conventionally, the color resist has to be coated on the substrate three times, but in the present invention, the filter base material 3 may be coated once on the substrate 1, thus reducing the number of steps, Efficient color filter R
F, GF, BF can be formed.

In the above embodiment, a roller was used as the dyeing means, but a squeegee was used instead of this roller, and the dye was spread on the hard mask by this squeegee and spread over a predetermined area of the filter substrate. You may make it dye a dye.

Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, as shown in FIG. 3 (A), IT is first formed over almost the entire area of the substrate 1 on which the black mask 2 is formed.
The electrode 6 made of a transparent conductive film such as O is uniformly formed.

Next, as shown in FIG. 3B, a hard mask 4a having a first predetermined pattern is formed on the electrode 6.
Place. Then, the first roller 5a is arranged on the hard mask 4a. A filter material in which a first color pigment such as a red pigment is dispersed in a resin is applied to the peripheral surface of the roller 5a.

Then, the roller 5a is replaced with the hard mask 4a.
And make it move in one direction while rotating. Along with this, the filter material adhering to the roller 5a is applied to a predetermined region on the electrode 6 through each opening 4a 'of the hard mask 4a, and the first color red color filter R
It becomes F.

When applying the filter material on the electrode 6, a voltage is applied to the electrode 6. The amount of the filter material adhered to the electrode 6 changes depending on the value of the applied voltage, and therefore the thickness of the filter material applied can be adjusted to a desired thickness by controlling the voltage.
After the first color red color filter RF is formed, it is washed with water and pre-cured. The curing method depends on the filter material, but a method of curing by heat treatment using a thermosetting resin material is preferable.

Next, as shown in FIG. 3C, the second hard mask 4b is placed on the substrate 1, and the second roller 5b is placed on the hard mask 4b. A filter material in which a second color pigment such as green pigment is dispersed in a resin is applied to the peripheral surface of the roller 5b.

The roller 5b is replaced with the hard mask 4b.
And make it move in one direction while rotating. Along with this, the filter material attached to the roller 5b is applied to a predetermined area on the electrode 6 through each opening 4b 'of the hard mask 4b, and the second color green color filter G is formed.
It becomes F.

When applying the filter material on the electrode 6, a voltage is applied to the electrode 6, and the thickness of the applied filter material is adjusted to a desired thickness by controlling this voltage. After the second color green color filter GF is formed, it is washed with water and pre-cured.

Next, as shown in FIG. 3D, the third hard mask 4c is placed on the substrate 1, and the third roller 5c is placed on the hard mask 4c. The peripheral surface of the roller 5c is coated with a filter material in which a blue pigment of the third color is dispersed in resin.

Then, the roller 5c is replaced with a hard mask 4c.
And make it move in one direction while rotating. Along with this, the filter material adhering to the roller 5c is applied to a predetermined region on the electrode 6 through each opening 4c 'of the hard mask 4c, and the third color blue color filter BF is applied.
Becomes

When applying the filter material on the electrode 6, a voltage is applied to the electrode 6, and the thickness of the applied filter material is adjusted to a desired thickness by controlling this voltage. After the third color blue color filter BF is formed, it is washed with water. Then, after this, all the color filters RF, GF, and BF are finally cured.

Through these steps, as shown in FIG. 3E, the red, green, and blue color filters R are formed on the electrodes 6.
F, GF, and BF are formed alternately. According to such a process, the hard masks 4a, 4b, 4c and the rollers 5a, 5b, 5c for each color are formed on the substrate 1 on which the electrodes 6 are formed.
Just by arranging
GF and BF can be formed. When a filter material is applied on the substrate 1, a voltage is applied to the electrode 6 on the substrate 1 and the voltage is controlled to adjust the applied film thickness to a desired film thickness. it can.

The electrode 6 formed on the substrate 1 can be used as a counter electrode in an active matrix type liquid crystal display element using a thin film transistor or the like as an active element. Further, also in the second embodiment, it is possible to use a squeegee instead of the roller and apply the filter material onto the electrode with this squeegee.

[0035]

As described above, according to the present invention, each time a color filter of one color is formed on the substrate, as in the case of the conventional photolithography, the color resist is coated on the entire surface of the substrate. Therefore, the number of steps is reduced and the manufacturing efficiency is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a first half step of a method for forming a color filter according to a first embodiment of the present invention.

FIG. 2 is a diagram showing the latter half of the same process.

FIG. 3 is a diagram showing steps of a method for forming a color filter according to the second embodiment of the present invention.

[Explanation of symbols]

 1 ... Substrate 3 ... Filter Base Material 4a, 4b, 4c ... Hard Mask 6 ... Electrode RF ... Red Color Filter GF ... Green Color Filter BF ... Blue Color Filter

Claims (3)

[Claims] 1. A method for forming a plurality of color filters on a substrate by a dyeing method, the plurality of color hard masks being unique to each of the plurality of colors and corresponding to the arrangement of the color filters of the respective colors. , A dyeable filter substrate is applied on the substrate to form a filter substrate film, and a corresponding hard mask is placed on the filter substrate film for each color. A corresponding color dye is applied to the filter base film through the dye, and the filter base film in the portion where the dye is applied is dyed in each color, thereby providing a color filter of a plurality of colors in a predetermined arrangement on the substrate. A method for forming a color filter, which comprises forming the color filter. 2. A method of forming a color filter of a plurality of colors on a substrate by using a filter material in which pigments of each color are dispersed and mixed, wherein the arrangement of the color filters of each color is unique for each color of the plurality of colors. A plurality of hard masks for each color having openings formed therein are prepared. For each color, a corresponding hard mask is placed on the substrate, and the corresponding filter material is transferred through the hard mask. A method for forming a color filter, which comprises forming a plurality of color filters of a predetermined color on a substrate by applying the filter material on the substrate and curing the applied filter material. 3. An electrode is formed on substantially the entire surface of the substrate, the hard mask for each color is placed on the electrode, and a voltage is applied to the electrode when the filter material is applied to apply a filter material coating film. The method for forming a color filter according to claim 2, wherein the thickness is adjusted.