JPH0593806A - Color filter and production thereof - Google Patents

Abstract

PURPOSE:To flatten over coat layers covering picture elements. CONSTITUTION:This color filter is constituted by depositing the over coat layers 6a, 6b, 6c tightly adhered with an org. high-polymer sheet atop a transparent substrate 1 formed with black matrix patterns 2 and the picture elements 3 to 5. The black matrix patterns 2 and the picture elements 3 to 5 are formed atop the transparent substrate 1 and a thermoplastic high-polymer sheet or thermoplastic and UV curing type high-polymer sheet is superposed thereon. The sheet is then pressed toward the transparent substrate 1 by a press plate 11 and is heated to the melting temp. of the sheet, by which the sheet is tightly adhered to the transparent substrate 1, the black matrix patterns 2 and the picture elements 3 to 5 and the front surface of the resin sheet is flattened. The resin sheet is thereafter heated up to its curing temp. or is irradiated with UV rays 12 and is thereby cured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a color filter used in a color liquid crystal display panel or the like and a method for producing the same, and in particular, when used in a color liquid crystal display panel by improving flatness, it improves display quality and at the same time, The present invention relates to a color filter and a method for manufacturing the same, which enables efficient manufacture of a flat film at low cost.

[0002]

2. Description of the Related Art As a color liquid crystal display panel whose demand is expanding to office automation equipment, personal computers, portable televisions, etc. due to its features such as thinness, light weight and low power consumption,
The simple matrix method and the active matrix method are known as typical ones.

The active matrix method is excellent in display quality, but is difficult to manufacture and has a drawback of high price. The simple matrix method is inferior to the active matrix method in display quality, but has an advantage that it can be manufactured at low cost.

In any case, three colors of R (red),
A color filter composed of G (green) and B (blue) pixels is formed, and pixels of these three colors are selectively driven to mix the colors so that arbitrary color display can be performed.

FIG. 6 is a sectional view for explaining a conventional method of manufacturing a substrate on which a color filter is formed for use in a color liquid crystal display panel. In FIG. 6A, 1 is a glass substrate, 2 is a black matrix pattern formed on the surface of the substrate 1, 3 is an R pixel, 4 is a G pixel, 5 is a B pixel, 6
Is a top coat layer, and 7 is a transparent electrode.

In FIG. 6 (a), a black matrix pattern 2 is formed on the surface of the substrate 1 by a vapor deposition film of metallic chromium, and then the black matrix pattern 2 is formed.
Pixels 3 to 5 are formed in an appropriate order so as to fill the large number of through holes.

Generally, the thickness of the black matrix pattern 2 formed of a vapor deposition film of metal chromium is about 1000Å,
The pixels 3 to 5 formed from the pixel film deposited by the spin coating method have a thickness of about 2 μm. In addition, in order to make the heights of the pixels 3 to 5 uniform, there is also one in which the pixels 3 to 5 are formed and then flattened, for example, polished.

In FIG. 6B, the top coat layer 6 for filling the unevenness due to the formation of the pixels 3 to 5 is generally formed by applying a coating film of a polyimide resin liquid or an acrylic resin liquid to a thickness of 2 to 2 by spin coating. After depositing to a thickness of about 4 μm, the unnecessary portion is removed and formed.

In FIG. 6C, a large number of transparent electrodes 7 arranged on the top coat layer 6 and aligned in the thickness direction of the drawing paper generally have their ends (connection terminals) on the surface of the substrate 1. Let it form.

[0010]

As described above,
The conventional color filter needs the top coat layer 6 for forming the transparent electrode 7 thereon, and the surface of the top coat layer 6 must be flat. However, as shown in FIG. 6C, the conventional top coat layer 6 has pixels 3 to
It is unavoidable that a concave portion having a depth of about several hundred Å corresponding to the above 5 is formed. For example, when a transparent electrode 7 having a thickness of about several thousand several hundred Å is formed thereon, the reliability of the transparent electrode 7 There was a problem that was damaged.

There is also a method of improving the spin coating method (multi-layer coating of resin film) or performing a polishing process in order to eliminate the concave portion of the top coat layer 6. However, the method of multilayering the resin film that is spin-coated multiple times does not sufficiently flatten the surface, and the method of performing the polishing process increases the cost.
In addition, there is a defect that the surface is easily scratched or dirt is easily attached.

[0012]

1 (a), (b) and (c) are explanatory views of the basic constitution of the method of the present invention. The color filter shown in FIG. 1 (a) is a black matrix pattern 2 , An organic polymer sheet having a cavity filling property, for example, a sheet obtained by softening xylene with a silicon gel sheet, is stacked on the substrate 1 on which the pixels 3 to 5 are formed, and is cured (evaporates xylene) to form a top coat layer. 6a is formed.

In the color filter shown in FIG. 1B, a thermoplastic resin sheet, for example, a polystyrene resin sheet is superposed on a substrate 1 on which a black matrix pattern 2 and pixels 3 to 5 are formed, and a pressing plate 11 having a smooth lower surface is used. The top coat layer 6b is formed by heating (melting) and pressing the resin sheet through the pressing plate 11 and the top coat layer 6b.
Is cooled and then removed.

In the color filter shown in FIG. 1C, a thermoplastic ultraviolet curable resin sheet such as a polystyrene UV resin sheet is superposed on the substrate 1 on which the black matrix pattern 2 and the pixels 3 to 5 are formed. The top coat layer 6c is formed by heating (melting) / pressing the resin sheet through the pressing plate on the lower surface, removing (or passing) the pressing plate, and irradiating with ultraviolet rays 12.

[0015]

FIG. 2 is a comparison diagram of the curing shrinkage characteristics of the styrene resin sheet for forming the topcoat layer according to the present invention and the curing shrinkage characteristics of the conventional topcoat layer forming liquid. In FIG. 2 in which the vertical axis represents the shrinkage ratio (%) and the horizontal axis represents the curing temperature (° C.), the shrinkage ratio of the conventional silicon-based resin liquid and acrylic resin liquid used for forming the topcoat layer is Although stable at a curing temperature of 200 ° C. or higher, their shrinkage ratio is 70% or more, whereas the styrene-based resin sheet used in the present invention has a shrinking property of a curing temperature of 200 ° C. or higher.
It is about 10%.

Therefore, in the conventional method using the resin liquid for forming the top coat layer, even if the upper surface immediately after the resin liquid is applied is flattened by the spin coating method, the thickness applied to the substrate 2 and the pixel 4 are applied. The thickness is different from the applied thickness, and the shrinkage rate is large at the time of curing treatment, so that the concave portion is formed.

On the other hand, according to the above means of using the resin sheet for forming the top coat layer, a part of the resin sheet flows between the pixels 4 when softened, and before curing, the upper portion of the substrate 2 and the pixels 4 are cured.
There is a difference in thickness from the upper part of the. Therefore, even if a resin sheet is used, a recess is formed on the surface of the top coat layer, but since the shrinkage rate of the resin sheet is significantly smaller than that of the resin liquid, the recess after curing is less than the recess formed by using the resin liquid. It becomes shallower than about / 7.

Further, the broad thickness unevenness peculiar to the resin sheet is eliminated by the self-flatness or the pressing treatment with the thermoplastic resin.

[0019]

EXAMPLE FIG. 3 is an explanatory view of a substrate for a color liquid crystal display panel according to an example of the present invention, and FIGS. 4 (a) to 4 (f) are explanatory views of a manufacturing process of the top coat layer shown in FIG.

In FIG. 3, reference numeral 1 is a substrate made of soda-lime glass having a thickness of 1.1 mm, and 2 is a thickness of 10 mm in the same manner as in the conventional method.
Black matrix pattern formed to about 00Å, 3
Is an R pixel, 4 is a G pixel, 5 is a B pixel, 10 is a top coat layer formed using a resin sheet, and 7 is a transparent electrode.

In FIG. 4A, a resin sheet 13 for forming a topcoat layer is laid over the surface of the substrate 1 on which the black matrix pattern 2 and the pixels 3 to 5 are formed,
As shown in (b), the resin sheet 13 is laminated on the surface of the substrate 2. At that time, when the resin sheet 13 is, for example, a softened silicon gel sheet with xylene, since the resin sheet 13 has a cavity filling property, it can be simply cured (evaporation of xylene) to obtain the top shown in FIG. When the coat layer 6a is completed and the transparent electrode is formed on the top coat layer 6a, the substrate for the color liquid crystal display panel is completed.

In FIG. 4C, the resin sheet 13 laminated on the surface of the substrate 2 on which the black matrix pattern 2 and the pixels 3 to 5 are formed is adhered to the substrate 1, the black matrix pattern 2 and the pixels 3 to 5. In the case of a thermoplastic resin such as a polyester resin or a bude resin having
For example, the resin sheet 13 is pressed through the pressing plate 11 having a smooth lower surface
When the resin sheet 13 is heated to 0 ° C. to be melted and pressed toward the substrate 1, and then the resin sheet 13 is heated to, for example, 200 ° C. to be cured, the top coat layer 6 b shown in FIG. If a transparent electrode is formed on the coat layer 6b,
The color liquid crystal display panel substrate is completed.

In FIG. 4D, the resin sheet 13 laminated on the surface of the substrate 2 on which the black matrix pattern 2 and the pixels 3 to 5 are formed is adhered to the substrate 1, the black matrix pattern 2 and the pixels 3 to 5. In addition, the top coat layer 6c (FIG. 1 (c)) formed by using such a resin sheet 13 has a pressing plate 11 like the top coat layer 6b. Resin sheet 13
After heating and melting to flatten the surface, press plate 11 is removed and ultraviolet rays 12 are radiated to cure to complete, and a transparent electrode is formed on top coat layer 6c. Is completed.

FIG. 5 is an explanatory view of the manufacturing process of the top coat layer according to another embodiment of the present invention. In FIG.
The top coat layer forming resin sheet 13 is made to face the surface of the substrate 2 on which the black matrix pattern 2 and the pixels 3 to 5 are formed. The resin sheet 13 is fixed to the lower surface of the surface plate 14, and the resin sheet 13 is adjusted by adjusting the position of the surface plate 14.
The position adjustment with respect to the substrate 1 can be performed, and the resin sheet 13 can be mounted on a predetermined portion of the substrate 1.

Next, as shown in FIG. 5B, the resin sheet 13 is moved to the pixels 3 to 5 by a laminator using a rotating roller 15 which presses the resin sheet 13 toward the substrate 1 while rotating.
Temporarily fix it to. However, if the surface plate 14 of FIG. 5A is configured to press the resin sheet 13 toward the substrate 1, the laminator using the roller 15 is unnecessary.

In FIG. 5C, numeral 16 is a vacuum pack made of a heat-resistant organic polymer, and a pressing plate 11 is placed on the substrate 1 on which the pixels 3 to 5 on which the resin sheet 13 is temporarily fixed are formed.
After they are sealed in the vacuum pack 16, the pressure inside the pack 16 is reduced, and the pressing plate 11 presses the resin sheet 13 toward the substrate 1 by the external pressure. Therefore, it is inserted into an autoclave device (heating and pressurizing furnace) to heat and pressurize.

When the resin sheet 13 is made of a thermoplastic resin, the heating by the autoclave device heats up to the melting temperature of the resin sheet 13 and, after a certain period of time, raises the heating temperature to the curing temperature of the resin sheet 13. Then, the pressurization by the autoclave device supplements the pressing force which is insufficient by the depressurization of the vacuum pack 16, and presses the resin sheet 13 against the substrate 1.

Then, by removing from the autoclave and cooling, and removing the vacuum pack 16 and the pressing plate 11, the top coat layer 6b shown in FIG. 1B is completed, and a transparent electrode is formed on the top coat layer 6b. Then, the substrate for the color liquid crystal display panel is completed.

Then, when the resin sheet 13 is made of a thermoplastic and ultraviolet curable resin, the heating by the autoclave device is carried out by heating to the melting temperature of the resin sheet 13 and taking out after a certain time, and passing through the vacuum pack 16 and the pressing plate 11 or After removal, the resin sheet 13 is irradiated with ultraviolet rays 12 as shown in FIG. 5D to complete the top coat layer 6c.

[0030]

As described above, according to the color filter and the method for producing the same of the present invention, the surface of the top coat layer is extremely easily flattened by forming the top coat layer using the resin sheet, and the liquid crystal When applied to the display substrate of the display panel, the effect of improving the reliability of the transparent electrode was obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a basic configuration of a method of the present invention.

FIG. 2 is a comparison diagram of curing shrinkage characteristics of a styrene resin sheet for forming a topcoat layer according to the present invention and curing shrinkage characteristics of a conventional topcoat layer forming liquid.

FIG. 3 is an explanatory diagram of a color liquid crystal display panel substrate according to an embodiment of the present invention.

FIG. 4 is an explanatory view of a manufacturing process of the top coat layer shown in FIG.

FIG. 5 is an explanatory view of a manufacturing process of a top coat layer according to another embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a conventional method of manufacturing a substrate on which a color filter is formed for use in a color liquid crystal display panel.

[Explanation of symbols]

 1 is a transparent substrate for forming a color filter 2 is a black matrix pattern 3 to 5 are pixels 6a, 6b, 6c, 10 are overcoat layers 11 are pressing plates 12 are ultraviolet rays 13 are organic polymer sheets

Claims (5)

[Claims] 1. A transparent substrate (1) on which a black matrix pattern (2) and a large number of pixels (3,4,5) are formed,
The black matrix pattern (2) and the pixels (3, 4,
A color filter comprising an overcoat layer (6a, 6b, 6c) adhered to an organic polymer sheet (13) so as to cover (5). 2. The color filter according to claim 1, wherein the organic polymer sheet (13) is a thermoplastic resin sheet. 3. The color filter according to claim 1, wherein the organic polymer sheet (13) is a thermoplastic and UV-curable resin sheet. 4. A black matrix pattern (2) and a large number of pixels (3,4,5) are formed on the upper surface of a transparent substrate (1), and the transparent substrate (1), the black matrix pattern (2) and the pixels are formed. Thermoplastic resin sheet with adhesion to (3,4,5)
(13) is placed on the upper surface of the transparent substrate (1), the sheet (13) is pressed by the pressing plate (11) toward the transparent substrate (1), and heated to the melting temperature of the sheet (13). , The resin sheet (13) is brought into close contact with the transparent substrate (1), the black matrix pattern (2) and the pixels (3, 4, 5) and the upper surface of the resin sheet is flattened, and then the resin sheet (13 ) Is heated to its curing temperature, a method for producing a color filter. 5. A black matrix pattern (2) and a large number of pixels (3,4,5) are formed on the upper surface of a transparent substrate (1),
A thermoplastic and UV-curable resin sheet (13) having adhesion to the transparent substrate (1), the black matrix pattern (2) and the pixels (3,4,5) is overlaid on the upper surface of the transparent substrate (2). , The sheet (13) is pressed against the transparent substrate (1) by the pressing plate (11) and heated, and the resin sheet (13) is heated to the transparent substrate (1), the black matrix pattern (2) and the pixel.
The resin sheet (13) is made to adhere to (3,4,5) and the upper surface of the resin sheet (13) is made flat, and then made flat.
A method for manufacturing a color filter, which comprises irradiating ultraviolet rays (12) to cure the resin.