JPH04238323A - Color liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent the generation of warpage in color filters formed by providing a black matrix on a plastic film and the nonuniformity of a cell gap when cells are formed. CONSTITUTION:A black resin is formed like gratings at a prescribed thickness of the plastic film substrate 1 to form the black matrix 2. Red, green and blue colored resins 4, 5, 6 are closely embedded between this black matrix 2 without overlaps to obtain the plastic color filters.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having a plastic color filter.

0002

2. Description of the Related Art FIG. 2 shows a general configuration example of a conventional color liquid crystal display device in cross section. A color filter 12 consisting of red, green, and blue (hereinafter referred to as R, G, and B, respectively) is disposed on one glass substrate 11, and a protective film 13 and an ITO electrode 14 are further formed on the color filter 12. . An ITO electrode 16 is formed on the other glass substrate 15. A pair of substrates 11 and 15 provided with electrodes and the like are placed facing each other after alignment treatment, and are sealed with a spacer 17.
A liquid crystal 18 is sealed inside to form a liquid crystal cell. A pair of polarizing plates 19 are provided on both sides of this liquid crystal cell.
20 are arranged to constitute a color liquid crystal display device.

[0003] In the color liquid crystal display device as described above, in order to improve the contrast of the image, a black matrix is formed between each pixel by separating each pixel with a light-shielding material (as described in ``'90 Thin Film Applied Electronics''). ``Device'' Press Journal, p160-163, March 5, 1990). Methods for forming the black matrix include a method using metal chromium or the like and a method using superposition of three colors R, G, and B. FIG. 3 is a cross-sectional view showing the structure of the vicinity of a color filter with a black matrix formed by the former method, in which a black matrix 22 made of metal chromium or the like is formed on a glass substrate 21, and R, G, and B colors are colored on top of the black matrix 22 made of metal chromium or the like. Layers 23 to 25 are formed, and an overcoat layer 26 and a transparent conductive layer 27 are further formed thereon. Also,
FIG. 4 is a cross-sectional view showing the structure of the vicinity of a color filter with a black matrix formed by the latter method, in which colored layers 32 to 34 of R, G, and B are formed on a glass substrate 31 by overlapping them as shown in the figure. Furthermore, an overcoat layer 35 and a transparent conductive layer 36 are formed thereon. In this example, a black matrix 37 is formed by overlapping R, G, and B.

0004

[Problem to be solved by the invention] However, thin films,
When a plastic film is used as a constituent substrate to reduce weight and a color filter is formed on the plastic film, if a black matrix is provided using a substance with strong film stress such as chromium, the substrate will be deformed. Also,
In the method of superimposing R, G, and B, the flatness of the substrate is impaired, making it impossible to control the gap of the liquid crystal cell.

It is an object of the present invention to overcome the drawbacks of the prior art and to provide a color liquid crystal display device that is free from color unevenness due to uneven cell gaps and has good contrast.

[0006]

[Means for Solving the Problems] In order to achieve the above object, according to the present invention, resins in which red, green, and blue pigments are dispersed are arranged between black resins constituting a black matrix without overlapping and without gaps. A color liquid crystal display device is provided, characterized in that it has an embedded plastic color filter.

[0007]

[Function] The present invention uses a color filter in which resins in which R, G, and B pigments are dispersed are embedded without overlap or gaps between a black matrix using a black resin of a predetermined thickness. Deformation of the board is prevented,
Gap control of the liquid crystal cell becomes easier and contrast becomes better.

[0008]

EXAMPLES The present invention will be explained in more detail below based on examples. In the color liquid crystal display device of this embodiment, R, G and
, which is characterized by the use of a color filter in which the resin in which the pigment B is dispersed is embedded without any gaps so that it is easy to overlap, and the other configuration is the same as that of the device shown in Fig. 2, so it will not be described here. The explanation will focus on color filters.

[0009] To describe the method for producing the color filter used in this example, first, as shown in FIG. 1(a),
On a substrate 1 made of a plastic film such as polyethylene terephthalate or polyether sulfone, 3 μm of acrylic colored photoresist in which black pigment is dispersed is applied.
After coating to a thickness of m, the length is 110μm and the width is 33μm.
A lattice-like pattern with m spacing and a width of 30 μm was formed to form a black matrix 2. Next, after coating a novolac-based photoresist 3, the film substrate 1 is coated.
The resist 3 is left only on the black matrix 2 (Fig. 1(b)), and then resins 4, 5, and 6 in which R, G, and B pigments are dispersed are printed using a printing method. It was transferred as shown in FIG. 1(c). In this case, regardless of whether photolithography or printing is used, a certain amount of margin is required depending on alignment accuracy and transfer accuracy. Therefore, in order to embed the colored resins 4, 5, and 6 between the black matrix 2 without any gaps, the black matrix 2 and the colored resins 4, 5, and
, 6 overlapped as shown in FIG. 1(c), and finally, the resin on the black matrix 2 was lifted off using a novolak photoresist. In this way, a plastic color filter shown in FIG. 1(d) was obtained.

[0010] When an STN type color liquid crystal display device was produced using the plastic color filter thus produced, there was no color unevenness due to uneven gaps and the contrast was good.

[0011]

Effects of the Invention As described in detail above, according to the present invention, by using a plastic color filter in which R, G, and B colored resins are embedded between the black matrix without any gaps, the gaps can be reduced. It is possible to realize a color liquid crystal display device with good contrast and no color unevenness due to irregularities in color.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a process for creating a color filter used in an example of the present invention.

FIG. 2 is a sectional view showing a general configuration example of a conventional color liquid crystal display device.

FIG. 3 is an explanatory diagram of a method of forming a black matrix using metal chromium or the like.

FIG. 4 is an explanatory diagram of a method of forming a black matrix by superimposing R, G, and B colors.

[Explanation of symbols]

1 Board 2 Black Matrix 3 Photoresist 4, 5, 6 Colored resin

Claims (1)

[Claims] Claim 1: A color characterized by having a plastic color filter formed by embedding resins in which red, green, and blue pigments are dispersed, respectively, into a black resin constituting a black matrix without overlapping and without gaps. LCD display device.