JPH08136714A - Production of color filter - Google Patents

Abstract

PURPOSE: To produce a color filter capable of forming a picture element eliminating a peeling from a substrate in a producing method for color filter forming a black matrix, R, G and B picture elements on a transparent substrate by exposing the rear side of the substrate at a colored picture element forming stage. CONSTITUTION: A red photosensitive resin layer is laminated on a glass substrate 2 on which a black matrix 1 of a Cr thin film has been formed previously by using a red dry film in which a colored photosensitive resin soln. consisting of a prescribed composition is made into film. Then, after executing registration by using a negative mask having a prescribed pattern, exposure is executed from the surface side of the substrate with a 3KW-super high voltage mercury vapor lamp, then, an unexposed part is removed to form a colored pattern of the first color. The second color is formed by using a blue dry film in the same manner. Moreover, after laminating green dry film, the exposure is executed from the rear side of the substrate without interposing the mask. Then, a similar development up to the second color is executed to form the picture of the third color.

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 color filter used in a color liquid crystal display device.

[0002]

2. Description of the Related Art Liquid crystal display (hereinafter abbreviated as LCD)
Taking advantage of its thinness, small size, and low power consumption, is currently used for display parts of watches, calculators, TVs, personal computers and the like. Furthermore, in recent years, color LCDs have been developed and OA / AV
It has begun to be used in many applications such as navigation systems and viewfinders mainly for devices, and the market is expected to expand rapidly in the future.

A color filter for displaying an LCD in color is R (red) on a substrate 2 such as a glass plate on which a BM (black matrix) 1 having a grid pattern is formed.
Color pixel 3 consisting of G (green) and B (blue) (approximately 100 x 1
(00 × 2 μm), and a transparent overcoat layer (OC) 4 is formed thereon. Reference numeral 5 is a polarizing plate, and 6 is an ITO electrode.

A color LCD has a color filter 7 as an LC.
The display screen can be colored by being installed inside D and transmitting the backlight light to the color filter. 8 is an alignment film, 9 is a liquid crystal, 10 is a seal material, 11 is a top coat layer, 12 is an ITO electrode, 13 is a substrate such as a glass plate, 14
Is a polarizing plate.

At present, color filters are mainly manufactured by the dyeing method. However, in this method, it is necessary to repeat the process of applying a transparent photosensitive resin on a glass substrate, forming pixels by drying, exposing and developing, dyeing with a dye, and then forming a color mixing prevention layer three times. Therefore, the number of steps is large and the cost is high. Further, since a dye is used as a colorant, there is a drawback that the reliability (weather resistance / heat resistance), which is an important subject of the color filter, is deteriorated.
Therefore, some color filters using a pigment as a colorant have been proposed, and among them, there are an electrodeposition method, a printing method, and a photolithography method (photolithography method).

However, the electrodeposition method requires the formation of an electrode pattern (1) the degree of freedom of the pattern is small,
(2) The cost is high, and the printing method has problems that (1) it is difficult to align a large-sized substrate and the resolution is low, so it is difficult to miniaturize, and (2) the flatness of the pattern is poor. The photolithography method is considered to be the mainstream. A liquid resist and a film are considered for the photolithography method. In the liquid resist, color pixels are formed by applying a varnish in which a pigment is dispersed in a photosensitive resin on a glass substrate with a spinner, drying, exposing, and developing. On the other hand, the film is a varnish formed into a film like the photosensitive film for printed boards, and after being laminated on a substrate, color pixels are formed by exposure and development.

[0007]

In the photolithography method, pixels are conventionally formed by exposing from the surface side of the substrate. However, since the varnish also contains a large amount of pigment in the liquid resist or film, the transmittance for the photosensitive wavelength is lower than that of a normal resist. For this reason, there is a problem that the resist near the substrate is insufficiently exposed to light and pixels are peeled off during development. The present invention provides a method for manufacturing a color filter that forms pixels that are not separated from the substrate.

[0008]

The present invention is a method of manufacturing a color filter for forming a black matrix, R, G, and B colored pixels on a transparent substrate such as a transparent plastic or glass substrate. In the process, the exposure is performed from the back surface side of the substrate.

When exposure is performed, it is possible to perform exposure from the back surface side of the substrate through a photomask. Further, the third color can be formed by using the color filters formed up to the second color as a mask. The R, G, and B pixels are preferably formed using a photosensitive dry film made of a photosensitive resin colored in one color with the base film.

[0010]

EXAMPLE A glass substrate (200 × 30) in which a BM of a Cr thin film is formed in advance using a red dry film formed by film-forming a colored photosensitive resin solution having a predetermined composition
A red photosensitive resin layer was laminated on 0 × 1.2 mm, Corning # 7059). The laminating conditions are a roll temperature of 120 ° C., a roll pressure of 4 kg / cm ² and a speed of 1.5 m / min. Then, alignment was performed using a negative mask having a predetermined pattern, and then exposure was performed from the substrate surface side with a 3 kW ultra-high pressure mercury lamp. After that, spray development was performed with a 2 wt% Na ₂ CO ₃ aqueous solution for 20 seconds to remove the unexposed portion, and 1
A tinted pattern was formed. Similarly, a second color was formed using a blue dry film. Further, after laminating a green dry film, the back surface of the substrate was exposed without a mask. After that, the same development as that for the second color was performed to form pixels for the third color. As a comparative example, exposure was performed from the substrate surface side through a mask to form a third color. Table 1 shows the exposure amount at the time of forming the third color and the pixel formation state after the development. O indicates that the pixels of the third color did not peel, and X indicates that peeling occurred.

[0011]

[Table 1] Exposure direction Exposure amount (mJ / cm ² ) 75 100 125 125 150 ─────────────────────────── Backside of substrate ○ ○ ○ ○ Substrate surface side × × × ○

[0010]

According to the present invention, it is possible to form pixels which are not separated from the substrate.

[Brief description of drawings]

FIG. 1 is a sectional view of a liquid crystal display.

[Explanation of symbols]

 1. BM (black matrix) 2. Glass substrate 3. Color pixel 4. Overcoat layer (OC) 5. Polarizing plate 6. ITO electrode 7. Color filter 8. Alignment film 9. Liquid crystal 10. Seal material 11. Top coat layer 12. ITO electrode 13. Glass substrate 14. Polarizer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuaki Takane 48 Wadai, Tsukuba City, Ibaraki Hitachi Chemical Co., Ltd. Tsukuba Development Laboratory (72) Inventor Ken Yoshida 48 Wadai, Tsukuba City, Ibaraki Hitachi Chemical Co., Ltd. Incorporated company Tsukuba Development Laboratory

Claims (1)

[Claims] 1. A black matrix on a transparent substrate,
A method of manufacturing a color filter for forming R, G, B colored pixels, wherein a method for manufacturing a color filter is characterized in that exposure is performed from the back surface side of the substrate in the colored pixel forming step.