JPH0355503A - Color separation filter - Google Patents

Abstract

PURPOSE:To obtain picture having good picture quality when used for a liquid crystal display device by forming colored picture elements of respective colored photosensitive resins and laminating the plural colored photosensitive resins on the regions to shield light, thereby forming light shielding layers. CONSTITUTION:The colored picture elements are formed of the respective colored photosensitive resins 2, 3, 4 and the light shielding layers 6 formed by lamination of the plural colored photosensitive resins are simultaneously formed on the regions to shield light. Namely, the light shielding layers 6 are formed by lamination of the colored photosensitive resins without separately forming the black light shielding layers and, therefore, the sensitivity and definition thereof are determined by the sensitivity and definition of the colored photosensitive resins. The light shielding layers 6 having the high resolution and sufficient black density are obtd. in this way. The images having excellent image quality are obtd. if such color sepn. filters are used for a liquid crystal display device. Further, the light shielding layers 6 are formed simultaneously with the process for production of the colored picture elements 2, 3, 4 and, therefore, the stages are shortened and the cost of production is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a color separation filter using a photosensitive resin in which pigments are dispersed.

[Conventional technology]

Color separation filters are made by repeatedly forming fine colored pixels of multiple colors on a substrate such as glass, plastic, or thin film transistor line sensor, and then providing a protective film on top of them. Various methods have been proposed for forming colored pixels, including the following.

(i) Staining - Photolithography method Proteins such as gelatin, glue, casein, etc. and PVA
Using a water-soluble polymer into which a dyeing group has been introduced and a photoreactive curing agent such as ammonium dichromate 5 diazo compound,
A method of sequentially shaping colored pixels through platemaking and dyeing processes.

(ii) Electrodeposition method The ionized pigment is separated in water, a voltage is applied to a transparent electrode patterned in advance, the ionized pigment is deposited on the transparent electrode, and this is repeated one after another to form colored pixels. How to get it.

(iii) depositing a sublimable dye or pigment on a substrate in a high vacuum;
Color pixels are obtained sequentially by a lift-off method or an etching method, or a multilayer interference thin film in which low refractive index materials and high refractive index materials are alternately laminated at a predetermined thickness is formed by a lift-off method or an etching method, and the pixels are sequentially colored. How to get pixels.

(1v) Printing method A pigment or dye with good transparency is separated into a vehicle,
A method in which each colored pixel is sequentially formed by screen printing, offset printing, or flexographic intaglio printing.

(v) ItI material - Photolithography method A method in which a pigment is dispersed in a photosensitive resin, and a color separation filter is formed by making a plate. This method includes, for example, JP-A-60-12
As disclosed in Japanese Patent No. 9738, there is a method in which the pigment particle size is made finer to obtain transparent colored pixels. This method is not only advantageous in terms of process since there is no dyeing or resist dyeing process, but it also surpasses the accuracy of photolithography in terms of accuracy and is superior to dyeing in terms of physical strength such as light resistance and chemical resistance. Furthermore, since there is no dyeing process, there are no cracks, and the physical reliability is high.Furthermore, since ion elution is extremely low, the electrical reliability is also high, and it is highly evaluated as a color separation filter.

[Problem to be solved by the invention] By the way, when manufacturing a color separation filter using a photosensitive resin in which such a pigment is dispersed, the photosensitive resin in which a black pigment is dispersed is used to form the light-shielding area. Ta. When a light-shielding area is formed using a photosensitive resin in which this black pigment is dispersed, there are the following problems.

That is, the first problem is resolution and black density.

Black pigment not only absorbs light in the visible range, but also absorbs ultraviolet light, so the photoreaction of photosensitive resins is slow, and
When exposed for a long time, unexposed areas near the surface of the photosensitive resin are exposed to light, resulting in a decrease in resolution. On the other hand, if the ratio of black pigment is decreased or the thickness of the black photosensitive resin is decreased in order to obtain high resolution, the black density will be insufficient and sufficient characteristics as a light-shielding layer will not be obtained. In other words, a light shielding layer satisfying both resolution and black density could not be obtained. The second problem is that in order to form a light-shielding layer, a photosensitive resin in which a black pigment is dispersed must be coated and plate-made, which makes the process complicated.

Alternatively, the light shielding layer can be formed by forming a metal thin film and performing plate making and etching using a photosensitive resin, but this increases the complexity of the process.

[Means to solve the problem]

The present invention was obtained as a result of intensive studies in view of the above problems, and the gist of the present invention is to provide color separations formed using a plurality of colored photosensitive resins in which pigments are dispersed in photosensitive resins. This color separation filter is characterized in that colored pixels are formed of each colored photosensitive resin, and at the same time, a light blocking layer is formed by laminating the plurality of colored photosensitive resins on a region to be light blocked. That is, the present invention does not form a black light-shielding layer separately, but forms a light-shielding layer by laminating colored photosensitive resins, so the sensitivity and resolution of the layer depends on the sensitivity and resolution of the colored photosensitive resin. There is no increase in the number of steps because the coloring pixels are formed at the same time as the colored pixels.

An example of the color separation filter of the present invention and its manufacturing method will be described below using specific examples.

〔Example〕

Red, green, and blue colored photosensitive resins were prepared by dispersing red, green, and blue pigments in a photosensitive resin in the proportions shown in the table below.

Surface colored photosensitive resin composition (unit: weight %) (1) Red photosensitive resin birazolone red (red pigment) 1
0 Vorivinyl alcohol/5% stilbazolium quinolium (photosensitive resin) ・・・5 Water ・・・・・・
...85 (2) Green photosensitive resin Lionol Green 2Y-301 (green pigment) ...9 Vorivinyl alcohol / 5% stilbazolium quinolium ...5
water ······
...86 (3) Blue photosensitive resin Fasdogen Blue (blue pigment) ...3 Polyvinyl alcohol/5% stilbazolium quinolium ...... 5
Next, a method for manufacturing a color separation filter according to the present invention will be explained using FIG.

(a) Thoroughly clean the 1.1 mm thick AL material made by Asahi Glass.

(b) On top of that, a red photosensitive resin was spin-coated to a thickness of 1 μm, dried in an oven at a temperature of 70°C for 30 minutes, and exposed using a mercury lamp to detect the spray phenomenon caused by water. This is carried out for 1 minute to obtain red relief pixels 2 on the area where red pixels should be formed and the area 6 where light should be blocked,
Furthermore, it was heat-cured at 150''C for 30 minutes.

(C) Repeat the same process to obtain green relief pixels 3 on the area where green pixels should be formed and the area 6 where light should be blocked, and blue relief pixels on the area where blue pixels should be formed and on the area 6 where light should be blocked. Pixel 4 was obtained.

(d) Finally, transparent resin 5 was applied to a thickness of 2 μm and cured by heating at 150° C. for 30 minutes to obtain a color separation filter of the present invention.

In this way, the light shielding layer 6 of the color separation filter of the present invention is
It is formed by laminating a red photosensitive resin, a green photosensitive resin, and a blue photosensitive resin, and a substantially black light-shielding layer that absorbs visible light is formed by laminating these three color resin layers.

When a liquid crystal display device was created using the color separation filter thus obtained and turned on, an image of good quality was obtained.

〔Effect of the invention〕

According to the present invention, a light-shielding layer having high resolution and sufficient black density can be obtained without impairing the characteristics of the color separation filter produced by the pigment-photolithography method. Therefore, the color separation filter of the present invention can be used in a liquid crystal display device. In this case, it is possible to obtain images of excellent quality. Furthermore, since the light-shielding layer is formed at the same time as the colored pixel manufacturing process, the process can be shortened, and the manufacturing yield can be improved and manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the manufacturing process of the color separation filter of the present invention. ■...Glass substrate, 2...Red relief image, 3
... green relief image, 4 ... blue relief image, 5 ... protective film, 6 ... light-shielding layer.

Claims (1)

[Claims] This is a color separation filter formed using a plurality of colored photosensitive resins made by dispersing pigments in the photosensitive resin, and at the same time as forming colored pixels with each colored photosensitive resin, the plurality of colored photosensitive resins are formed on the area to be light-shielded. A color separation filter characterized by forming a light-shielding layer by laminating colored photosensitive resin.