JPH07333593A - Production of light shielding film - Google Patents

Abstract

PURPOSE:To improve the printing line accuracy of a light shielding film forming the apertures of pixels of color filters in a process for producing the light shielding film of the color filter to be used for a color information device, etc. CONSTITUTION:After a positive resist 2 is applied on a transparent substrate 1, this positive resist is exposed via a photomask 3 for exposing the regions corresponding to the light shielding film 6 and is developed, by which relief parts 4 are formed. The glass substrate 1 formed with such relief parts 4 is coated with a photosensitive resin black 5 of a photosetting type by applying or printing and is then exposed from both surfaces of the glass substrate 1 coated with this photosensitive resin black 5. The positive resist 2 remaining as the relief parts 4 is lifted off by a developer, by which the light shielding film 6 is 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 manufacturing a light-shielding film for a color filter used in a color liquid crystal display device or the like. In particular, the present invention relates to an improvement in improving the drawing accuracy of the light-shielding film that forms the opening of the pixel of the color filter.

[0002]

2. Description of the Related Art A color filter used in a color liquid crystal display device or the like is usually R (red) G (green) on a transparent substrate.
Three colors of B (blue) are arranged side by side.

FIG. 2 is a plan view of a color filter, showing an example of an array of three colors. In FIG. 2, (a) is a rectangular mosaic arrangement, (b) is a triangle arrangement, and (c) is a stripe arrangement. In each case, the different colors are arranged next to each other and are spaced apart from each other. Reference numeral 6 is a light-shielding film that separates different colors. 7 is a colored portion, R is a red colored layer, G is a green colored layer, and B is a blue colored layer. Each of R, G and B is formed in a predetermined colored portion 7 according to the shape of the arrangement.

Conventionally, the light shielding film 6 is formed in the following steps. That is, a photocurable photosensitive resin black is applied on a transparent substrate, the photosensitive resin black is exposed through a photomask that exposes a region corresponding to the light-shielding film 6, and the photosensitive resin black is cured and developed. By doing so, the light-shielding film 6 was formed by dissolving the unexposed photosensitive resin black. Then, the colored layers R, G, and B of three colors are sequentially formed to form a color filter.

[0005]

The light-shielding film 6 determines the amount of transmitted light, that is, the aperture related to the gradation of light and shade, and the pitch accuracy and the aperture ratio of the pixel are regulated by the light-shielding film 6. Therefore, the shading film 6 is required to have a high drawing accuracy. Further, since it is used in combination with a transparent pixel electrode such as a thin film transistor or ITO, it is required to have the same drawing accuracy as that of the thin film transistor or pixel electrode. For this reason, a photolithography method is used which can manufacture the light shielding film with high accuracy. By the way, although the light-shielding film 6 formed by using the photosensitive resin black is manufactured by the photolithography method, the light-shielding film 6 is formed.
The edge shape was distorted and the drawing accuracy was not sufficient.

An object of the present invention is to solve this problem, and to provide a method of manufacturing a light-shielding film, which can obtain a light-shielding film with good drawing accuracy.

[0007]

Means for Solving the Problems The above-mentioned object is achieved by applying a positive resist (2) to a transparent substrate (1) and then exposing a region corresponding to a light-shielding film (6) through a photomask (3). An embossed portion (4) is formed by exposing and developing, and a photocurable photosensitive resin black (5) is applied or printed on the glass substrate (1) on which the embossed portion (4) is formed. And then exposed from both sides of the glass substrate (1) coated with the photosensitive resin black (5) to develop the positive resist (2) remaining as the relief portion (4). This is achieved by a method of manufacturing a light-shielding film in which the liquid is lifted off and the light-shielding film (6) is formed.

[0008]

In the method of manufacturing the light-shielding film according to the prior art,
The photocurable photosensitive resin black 5 was used, and the light-shielding film 6 was formed directly by the photolithography method. Since the photosensitive resin black 5 used for the light-shielding film 6 is a resin having a high optical density as a matter of course, it is necessary to increase the exposure amount in order to cure it. It is exposed from one side through. Since the light source used for the exposure is limited, the exposure amount is secured by performing the exposure for a long time. When the exposure time becomes long, the edge shape of the light-shielding film 6 is distorted due to thermal distortion and the like, and the drawing accuracy is deteriorated.

In the method of manufacturing the light-shielding film according to the present invention, first, the positive resist 2 is formed with the relief portion 4 by the photolithography method, and the photosensitive resin black 5 is formed thereon.
And then exposing from both sides, the positive resist 2 is dissolved with a developing solution to form the light shielding film 6. Positive resist 2
Has a high image precision, and the photosensitive resin black 5 formed in the above process faithfully inherits the high image precision of the positive resist 2 and has a high image precision.

Further, the exposure to the photosensitive resin black 5 only hardens the photosensitive resin black 5 and softens the positive resist 2 of the relief portion 4, and the photosensitive resin black of the non-opening portion is formed as in the prior art. Since it is not necessary to cure only 5, it is possible to perform exposure from both sides of the transparent substrate 1 without the need for a mask. Therefore, the exposure can be completed in about half the time as compared with the conventional case. Therefore, it is possible to prevent the drawing accuracy of the light shielding film 6 from deteriorating.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a light shielding film according to one embodiment of the present invention will be described in more detail below with reference to the drawings.

FIG. 1 is a view showing a method of manufacturing a light shielding film according to one embodiment of the present invention in the order of steps.

In FIG. 1 (a), 1 is a transparent substrate made of glass or the like, and 2 is a positive resist coated on the transparent substrate 1 such as AZ-1350 manufactured by Shipley, USA. The positive resist 2 is applied by spin coating at 1200 rpm for 10 seconds. The coating amount is set to a film thickness of 0.3 to 1.0 μm after the pre-baking which is the next step. The prebaking is at 90 ° C. for 30 minutes. Reference numeral 3 denotes a photomask, and the shaded area is an area for blocking light rays for exposure indicated by an arrow. Then, the place corresponding to the light-shielding film 6 of the color filter is adapted to shield light. The exposure amount is 10 mJ / cm ² .

In FIG. 1 (b), 4 is a relief portion,
After the exposure step, it was formed by developing with a developing solution containing 800 g of sodium hydroxide, 1000 g of sodium carbonate and 200 liters of water.

In FIG. 1 (c-1), 5 is a photosensitive resin black such as BRK-220 manufactured by Nippon Kayaku Co., Ltd., which is applied by spin coating at 800 rpm for 10 seconds. The coating amount is set to be about 1.0 μm after post-baking, which is performed later, and is slightly thicker than the relief portion 4. Prebaking is 110 degreeC and 5 minutes. After prebaking, the transparent substrate 1 is exposed from both sides. The exposure dose on each side is 100 mJ / cm ² . The arrows indicate the rays of exposure.

FIG. 1 (c-2) shows a state in which printing coating is applied instead of the coating coating of FIG. 1 (c-1). In the case of a print coat, printing is performed while avoiding the relief portion 4. The printing film thickness, pre-baking, and exposure are all as described in FIG. 1 (c-1).

In FIG. 1D, 6 is a light shielding film,
After the exposure step of FIG. 1 (c-1) or FIG. 1 (c-2),
800g sodium hydroxide and 1000g sodium carbonate
It was formed by developing with a developing solution containing 200 liters of water and 200 liters of water.

With the above, the manufacture of the light-shielding film according to the first embodiment is completed. At this time, the film thickness of the light-shielding film 6 was 1.0 μm, the optical density OD was 2.3 or more, and it was possible to obtain a drawing accuracy comparable to that of a thin film transistor or a pixel electrode.

The colored layer of the color filter is formed by a photolithography method, a printing method, an electrodeposition method or the like. A simple example of a pigment dispersion method using a photolithography method is as follows. First, CR-20 manufactured by Fuji Hunt Co., Ltd.
A photoresist containing a pigment such as 00 is spin-coated at 1000 rpm for 10 minutes to a film thickness of about 1.2 μm after post-baking, and then pre-baked at 70 ° C. for 20 minutes. Then, the red pattern is exposed to a mask of 120 mJ / cm ² and developed with a developing solution CD, and then post-baked at 230 ° C. for 1 hour to form a red colored layer. Similarly, CG-20
00 or CB-2000 pigmented photoresist is used to successively form a green or blue colored layer.

[0020]

As described above, according to the method of manufacturing the light-shielding film of the present invention, the relief portion is formed by the photolithography method using the positive resist, and the photocurable photosensitive resin is formed thereon. Cover black, expose from both sides,
The photosensitive resin black is cured to soften the relief.
The light-shielding film is formed of the remaining photosensitive resin black by melting the softened relief portion.

As described above, since the photosensitive resin black is formed by using the relief portion made of the positive resist having excellent image drawing accuracy, the photosensitive resin black also has high image drawing accuracy. Further, since the photosensitive resin black is exposed from both sides when it is exposed, it is possible to shorten the exposure time and cure without degrading the image precision. For this reason, the light-shielding film has a high image precision, and has sufficient precision as a light-shielding film for a color filter of an image display device or the like.

[Brief description of drawings]

FIG. 1 is an explanatory view showing steps of a method of manufacturing a light shielding film according to the present invention.

FIG. 2 is a plan view of a color filter.

[Explanation of symbols]

 1 transparent substrate 2 positive resist 3 photomask 4 embossed portion 5 photosensitive resin black 6 light-shielding film 7 colored layer

Claims (1)

[Claims] 1. An embossed portion is obtained by applying a positive resist (2) to a transparent substrate (1), exposing it through a photomask (3) which exposes a region corresponding to a light-shielding film (6), and developing it. (4) is formed, and the glass substrate (1) on which the relief portion (4) is formed
Is coated with a photocurable photosensitive resin black (5) by coating or printing, and then exposed from both sides of the glass substrate (1) coated with the photosensitive resin black (5),
A method of manufacturing a light-shielding film, characterized in that the positive resist (2) remaining as the relief portion (4) is lifted off with a developing solution to form a light-shielding film (6).