JPH01188802A - Manufacture of color filter - Google Patents

Abstract

PURPOSE:To obtain a highly flat color filter without being influenced by the surface shape of a substrate by applying a smoothing agent having a prescribed clearance on the surface of a color filter substrate to form a color filter part with a doctor knife and flattening the surface of the color filter substrate with a smoothing agent. CONSTITUTION:While the leg part of a doctor knife 41 is abutted on the glass plate of a substrate 11, the doctor knife 41 is moved from the edge part of the substrate 11 to another edge part and a smoothing agent 21 is applied. The application film thickness of the smoothing agent 21 at this time is specified by the dimension of the clearance of the doctor knife 41. Consequently, the dimension from the surface of the substrate 11 to the surface of the smoothing agent 21 is made constant at any position of the substrate 11 regardless of the presence and absence of a color film part 1. Thus, the unevenness of a color filter part surface can be flattened and the level difference between the color filter part and the space part of the color filter part can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of manufacturing a color filter used in a color liquid crystal display element.

A conventional liquid crystal display element is basically constructed by sandwiching a liquid crystal between two electrode substrates. When constructing a color liquid crystal display element, color filter portions 1 of three primary colors, namely red IR, green 1G, and blue IB, are formed in a stripe or mosaic pattern on one substrate 1), as shown in FIG. A transparent electrode 31 is formed on this color filter section 1. A transparent electrode 32 is formed on the other substrate 12. The liquid crystal LC is sandwiched between these two substrates 1) 12. In the color display element configured as described above, the white incident light passes through the substrate 1) and passes through the color filter section 1 to select the spectral components, and then the amount of light transmitted is adjusted by the liquid crystal LC, which is a light shutter. The light components that have passed through the substrate 12 are seen as emitted light and colored light is observed by humans.

As a method of forming the color filter section on a substrate at low cost, a method of printing pigment ink on the substrate using a flat plate or intaglio method has been proposed.

Problems to be Solved by the Invention However, when a color filter section is formed using the printing method described above, the surface of the color filter section has large irregularities as shown in FIG. 5, which may disturb the alignment of liquid crystal molecules or cause cells to There are problems such as non-uniformity of the gap, which causes display unevenness.

In order to improve these above-mentioned problems, as shown in FIG. Methods are being considered to reduce the unevenness of the surface. However, as shown in FIG. 6, in this method, the smoothing agent is formed on the surface of the color filter substrate to have a uniform thickness, so the large step difference between the color filter part and the space of the color filter part is eliminated. If this remains unresolved and a thin line of a transparent electrode thin film is formed on this smoothing agent, there is also the problem that the step may cause the thin electrode line to break.

The present invention has been made in view of the above-mentioned problems, and is a color filter that can flatten the unevenness on the surface of the color filter part and eliminate the difference in level between the color filter part and the space of the color filter part. The present invention provides a method for manufacturing.

Means for Solving the Problems In order to solve the above problems, the present invention includes a step of forming a color filter section on the surface of a substrate, and a step of applying a smoothing agent to the surface of the color filter substrate on which the color filter section is formed at a predetermined gap. The method includes the step of coating the color filter substrate with a doctor knife and flattening the surface of the color filter substrate with a smoothing agent.

Function The present invention produces color filter substrate 1 by the above-described manufacturing method.
surface is flattened.

The reason for this is that the smoothing agent is applied onto the substrate on which the color filter portion is formed using a doctor knife having a certain gap. That is, as shown in Figures 1 and 2,
While placing the legs of the doctor knife 41 on the glass sheet 1 of the substrate 1), place the doctor knife 41 on the substrate 1).
) from one end to the other end and apply the smoothing agent 21.
is applied.

The coating thickness of the smoothing agent 21 at this time is
Determined by the size of the gap. Therefore, as shown in FIG. 2, the dimension from the surface of the substrate 1) to the surface of the smoothing agent 21 is the same regardless of whether the color filter section 1 is
It remains constant at any position in the throat. Therefore, as shown in FIG. 3, not only the surface of the color filter section 1 can be flattened, but also the space between, for example, the red IR and the green IG of the color filter section 1 can be flattened.

EXAMPLE Hereinafter, a method for manufacturing a color filter according to an example of the present invention will be described with reference to the drawings.

In the present invention, first, red, green, and blue pigment inks are printed on a substrate 1) made of transparent glass using a lithographic offset method so that the film thickness after baking is 2 μm. (Red IR, Green IG, Blue I
B) into a stripe with a line width of 200 μm and a pinch of 240 μm.
The ink is then heated to harden the binder resin in the ink. Next, as shown in FIG. 1, a doctor knife 41 with a predetermined gap is placed at the end of the substrate 1) on which the color filter section 1 is formed.

At this time, the leg of the doctor knife 41 is set so as to be in contact with the glass surface of the substrate 1). Then, apply a smoothing agent 21 made of acrylic resin to the front of the doctor knife 4■,
The doctor knife 41 is pressed against the substrate 1) and moved at a constant speed to the other end of the substrate 1) to apply the smoothing agent 21. FIG. 1 shows the application state of the smoothing agent 21 by the doctor knife method, and the arrow in the figure shows the direction of movement of the doctor knife 41. FIG. 2 is a sectional view of the smoothing agent cloth as seen from the front.

As can be seen in FIG. 2, the film thickness of the applied smoothing agent 21 is determined by the dimension of the gap provided in the doctor knife 41, and the dimension from the surface of the substrate 1) to the surface of the smoothing agent 21 is determined on the substrate 1). It will be the same in any position. Therefore, as shown in FIG. 3, not only the surface of the color filter section 1 can be flattened, but also the space between red IR and green IG of the color filter section 1, for example, can be flattened.

As described above, the present invention allows smoothing of the smoothing agent 21 without depending on the surface shape of the substrate 1) on which the color filter section 1 is provided.
can be coated with good smoothness, making it possible to obtain a color filter with a flat surface.

The unevenness on the surface of the color filter section thus obtained (the surface on the smoothing agent 21 applied on the color filter section 1) is reduced and improved as shown in FIG. 4.

In the embodiments of the present invention, the color filter portions are formed by printing, but the present invention is also effective when forming the color filter portions by other forming methods (e.g., electrodeposition) because of the flattening effect. It is.

Furthermore, although the color filter according to the embodiment of the present invention has a structure in which no light shielding layer is provided between each color, for example, between red IR and green IG, even in the case of a color filter structure in which this light shielding layer is provided, this portion If there is a difference in level, the method of the present invention can flatten it, so the present invention is effective.

Further, when the color filter is formed in a pattern other than the striped pattern of the embodiment of the present invention, the present invention is also effective with other pattern configurations such as a mosaic pattern.

Effects of the Invention As described above, according to the present invention, a color filter with high flatness can be obtained by a simple method without being affected by the surface shape of the substrate on which the color filter portion is provided. . Furthermore, according to the present invention, the stepped portion between the color filter section and the space of the color filter section is also flattened, so even if a thin transparent electrode wire is formed on the color filter of the present invention, this thin electrode wire is electrically connected. There are also some that do not cause disconnection.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a state in which a smoothing agent is applied to the surface of a substrate on which a color filter portion is formed in one embodiment of the present invention, and FIG. 2 is a sectional view of the state shown in FIG. 1 when viewed from the front. , FIG. 3 is a sectional view of a color filter according to an embodiment of the present invention, FIG. 4 is an explanatory diagram showing the roughness of the color filter surface at a position where a color filter section is provided in an embodiment of the present invention, and FIG. The figure is an explanatory diagram showing the surface roughness on the color filter part using the printing method, Figure 6 is a cross-sectional view of the color filter coated with a smoothing agent using the conventional roll coater method, and Figure 7 is used to explain the color liquid crystal display element. FIG. ■・・・Color filter section (IR: red, IG-
Green, IB: Blue), 1)... Board, 21...
... Smoothing agent, 41 ... Doctor knife. Name of agent: Patent attorney Toshio Nakao One idiot! ”-Force Rafi λ Leg part 1) - L version 2/-11 y # 箮 1 41- Doctor knife Fig. 1 t Fig. 2! Figure 5 (Fried sails)

Claims (2)

[Claims] (1) Forming a color filter section on the substrate surface;
A color filter comprising the step of applying a smoothing agent to the surface of the color filter substrate on which the color filter portion is formed using a doctor knife having a predetermined gap, and flattening the surface of the color filter substrate with the smoothing agent. Manufacturing method. (2) The method for manufacturing a color filter according to claim (1), wherein the color filter portion is formed by printing pigment ink on the surface of the substrate.