JPH08248411A - Color filter substrate for liquid crystal display, manufacturing method thereof, and liquid crystal display - Google Patents

Abstract

(57) [Summary] [Object] To omit the conventional step of forming spacers only, and simultaneously to form a convex portion having a spacer function when forming a color filter layer to simplify the step.
In addition, it is to form a convex portion having a spacer function that does not cause disturbance of optical characteristics. Further, it is intended to make the heights of the convex portions having a spacer function uniform. A color filter substrate for a liquid crystal display, comprising: a transparent substrate; a color filter layer formed on the transparent substrate to form a pixel; and a transparent conductive film formed on the color filter layer. The color filter layer includes a pixel made of each coloring material and at least three pixels.
A plurality of convex portions having a substantially uniform height formed by stacking colored materials of different colors are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter substrate for a liquid crystal display, a method for manufacturing the same, and a liquid crystal display using a liquid crystal.

[0002]

2. Description of the Related Art Generally, in a color filter substrate, after a black matrix is arranged and formed on a transparent substrate at a predetermined position, red (R), green (G) and blue (B) color filter layers are formed on the transparent substrate. The dyeing method, electrodeposition method, printing method,
The pattern is formed by a pigment dispersion method or the like. A top coat layer is formed on the color filter layer to protect the color filter layer and improve the flatness of the surface. This is also called an OP layer. And
A transparent conductive film layer is formed on the top coat layer to form a color filter substrate.

Further, a liquid crystal display is constructed by providing the color filter substrate and an opposite substrate so as to face the substrate and enclosing liquid crystal in a gap formed by joining these substrates. In such a liquid crystal display, particles called spacers are dispersed between the substrates in order to keep the gap for enclosing the liquid crystal substantially constant.

[0004]

However, in the conventional liquid crystal display technology, providing a step only for forming spacers has a large negative side in view of productivity, and the spacers are scattered. The process itself of doing is being reviewed. Further, since the conventional spacers of particles have the property of dispersing light, the spacers are exposed to the light, and the light is scattered, which adversely affects the optical characteristics.

In relation to such a technique, Japanese Patent Laid-Open No. 6-1
Japanese Patent Publication No. 74915 discloses that a gap black portion having a spacer function is formed, but in the end, the conventional spacer spraying process is merely changed to a process of forming the gap black portion. The number of processes cannot be reduced. Further, it can be said that it is difficult to make all the heights of the gap black portion having the spacer function uniform.

The present invention has been made in view of the above circumstances, and an object thereof is to omit the conventional step of forming spacers only and to form a convex having a spacer function at the same time when forming a color filter layer. The purpose is to form parts to simplify the process. In addition, it is to form a convex portion having a spacer function that does not cause disturbance of optical characteristics. Further, it is intended to make the heights of the convex portions having a spacer function uniform.

[0007]

In order to achieve such an object, a color filter substrate for a liquid crystal display of the present invention comprises a transparent substrate and a color filter layer which is formed on the transparent substrate and constitutes a pixel. And a transparent conductive film formed on the color filter layer, and the color filter layer is formed by partially laminating a coloring material of at least three colors with a pixel made of each coloring material. It is configured to include a plurality of convex portions having substantially uniform height.

In the present invention, the projections having a substantially uniform height are formed by superposing a transfer film having a coloring material formed on the base material in advance on a transparent substrate, and then peeling the base material to remove the coloring material. Is formed by stacking at least three colors of coloring materials by repeating a transfer operation of transferring to the transparent substrate.

Further, in the liquid crystal display of the present invention, the color filter substrate for a liquid crystal display and a substrate having a plurality of electrodes are provided with a convex portion having a substantially uniform height formed on the color filter substrate for a liquid crystal display. And the liquid crystal material is sealed in the gap formed by the convex portion.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a color filter substrate 1 for a liquid crystal display (hereinafter, simply referred to as “color filter substrate 1”) of the present invention is formed on a transparent substrate 11 and the transparent substrate 11. It has a color filter layer (red (R), green (G), blue (B)) that constitutes a pixel and a transparent conductive film layer 41 formed on this color filter layer. The color filter layer includes pixels made of each coloring material and convex portions 7 having a substantially uniform height formed by partially laminating coloring materials of at least three colors.

In the example of FIG. 1, the convex portion 7 has a red (R) color.
R ', a green (G) coloring material formed so as to cover the convex piece (coloring material (piece)), and a blue (B) convex piece (coloring material (piece) )) B '. A specific method of forming the convex portion 7 will be described later.

Generally, a black matrix 21 is formed in a predetermined pattern between the color filter layers forming each pixel as shown in FIG. 1, and a color filter layer is formed on the color filter layer. A top coat layer 31 (also referred to as an OP layer) is formed to protect the layer and improve planar flatness.

In the present invention, the color filter layers (R,
The G and B) and the convex portion 7 are formed by a so-called transfer method or the like, and are usually formed by patterning using a photolithography technique. That is, prepare a transfer film on which a coloring material having photosensitivity is formed in advance on a substrate,
A transfer operation of superposing this on the transparent substrate 11 (applying heat and pressure as necessary), exposing and developing, and then peeling the base material to transfer the coloring material onto the transparent substrate 11. Is repeated. In particular, in order to form the convex portion 7, the coloring materials of three colors of R, G and B are stacked at least. However, when the embossing transfer method of transferring the coloring material to the transparent substrate by pressing the transfer film with the embossing member on which the color filter pattern is already formed, the photolithography technique is not necessary.

In any case, in the present invention, when the transfer film is used, the thickness of the coloring material is determined when the coloring material is formed on the transfer film.
The thickness of the coloring material can be determined more accurately than by applying the coloring material with a spin coater. That is, the height of the convex portion 7 can be accurately determined. Further, compared to a method of coating an expensive colored photosensitizer on a substrate with a spin coater (rotary coating method), the transfer method does not have a problem that the colored photosensitizer is scattered and thrown away by rotation, which is cost-effective. However, there is an advantage that the side surface and the back surface of the substrate are not coated with the sensitizer, and there is no concern about the occurrence of defective foreign matter in the subsequent process.

FIG. 9 shows a typical basic layout of the color filter. There are a mosaic type, a stripe type, a triangle type, and a 4-pixel arrangement type. Two examples of forming the convex portion 7 will be described based on the basic layout.

First, one method is a method of forming convex portions 7 on a line of one color at regular intervals in a stripe type, and a concrete example of this method is shown in FIGS.

As shown in FIG. 2, first, a red (R) stripe is formed as a coloring material on a transparent substrate.
Here, in order to finally form the convex portion 7 in the green (G) region, in addition to the original red (R) stripe, a red (R) convex piece (coloring material (piece)) R'is formed in predetermined locations in the green (G) area (four in the illustrated example).

Next, as shown in FIG. 3, green (G) stripes are formed as a coloring material on the transparent substrate. The green (G) stripe covers the red (R) convex piece R ′ that has been previously arranged at a predetermined position in the green (G) region.

Next, as shown in FIG. 4, blue (B) stripes are formed as a coloring material on the transparent substrate. Here, in addition to the original blue (B) stripe, the blue (B) convex piece (coloring material (piece)) B ′ is replaced by the red (R) convex piece (coloring material (piece)) R ′. Is formed on the upper surface of the substrate through a green (G) stripe.

By such a series of operations, the convex portion 7 becomes
It is formed along with the formation of colored materials (red (R), green (G), and blue (B)) that form the color filter layer. An overall sectional view of this state is shown in FIG. This convex portion 7
Since three colors of red (R), green (G), and blue (B) are stacked, they become black dots. However, in reality, it is a minute point, so there is no problem in practical use (in the drawing, the convex portion 7 is enlarged for easy understanding). The thickness of each coloring material (piece) is constant.
Therefore, the heights of the convex portions 7 in the transfer method are all highly uniform.

The second method of forming the convex portions 7 is a method of finally forming the convex portions 7 on all lines of each color at constant intervals in the stripe type, and a concrete example of this method is shown in FIG. It is shown in FIG.

First, as shown in FIG. 5, red (R) is formed as a coloring material on a transparent substrate. Here, finally, the convex portions are formed on all the lines of each color, so that in addition to the original red (R) stripe, the red (R) convex portion pieces R ′ are green (G) and blue (B). ) Is formed at a predetermined location in the area.

Next, as shown in FIG. 6, green (G) is formed as a coloring material on the transparent substrate. even here,
Finally, since it is necessary to form the convex portions on all the lines of each color, in addition to the original green (G) stripe, the green (G) convex portion piece G'is provided at a predetermined position of the red (R) stripe. It is formed on the upper part and on the red (R) convex part R ′ already formed in the blue (B) region, respectively. In addition, the green (G) stripe covers the red (R) convex piece R ′ that was previously formed at a predetermined position in the blue (B) region. From the perspective of the drawing, the protruding piece drawn out by the dotted lead line is not located at the top, but is in a state of being covered in some form, and is drawn out by the solid lead line. The convex piece means that it is located at the top.

Next, as shown in FIG. 7, blue (B) is formed on the transparent substrate. Here again, since it is necessary to finally form all the convex portions on the lines of each color, in addition to the original blue (B) stripes, the blue (B) convex portion pieces B '
On the convex portion G ′ of green (G) already formed in the red (R) area, and covered by the green (G) stripe already formed in the green (G) area. It forms respectively on the convex part R'of red (R).

By such a series of operations, the convex portion 7 becomes
It is formed along with the formation of colored materials (red (R), green (G), and blue (B)) that form the color filter layer. The convex portion 7 has three colors of red (R), green (G), and blue (B).
As a result of the color lamination, black spots are formed, but in reality, they are minute spots, so that there is no problem in practical use as described above.

As described above, the top coat layer 31 is usually provided to protect the color filter layer on the color filter layer and improve the surface flatness.
Is formed. Furthermore, a transparent conductive film layer 41 (I
TO) is formed to form a color filter substrate.
As shown in FIG. 1, the top coat layer 31a and the transparent conductive film layer 41a are also formed on the convex portion 7. The top coat layers 31, 31a, the transparent conductive film layer 41,
41a is generally formed by a sputtering method or the like. However, when the transparent conductive film layer 41 and the transparent conductive film layer 41a on the convex portion 7 are connected, a counter substrate for forming a liquid crystal display, which will be described later, is formed. It will short-circuit with the transparent conductive film. In order to prevent this, it is preferable to mask the convex portion 7 in advance to form the transparent conductive film layer 41. Of course, it may be formed as shown in FIG. 1 without masking. In this case, when forming the blue (B) convex piece B ′, if the blue color of the convex piece B ′ can be formed in an inverted trapezoidal shape when overdeveloped, the convex conductive film 41a and the transparent conductive film 41a having a convex shape are usually formed. It may be formed without connecting the transparent conductive film 41 to the colored layer. In any case, if the smoothness of the colored layer is within a range that does not pose a problem, the top coat layer 3
1,31a may be omitted.

Using the color filter substrate 1 for a liquid crystal display thus formed, although not shown in the drawing, a plurality of electrodes are newly added through the projections 7 of substantially uniform height formed on the substrate. A liquid crystal display is formed by joining a substrate having a substrate and a liquid crystal material in the gap formed by the convex portion 7. As the liquid crystal material to be enclosed, various known materials are used.

[0029]

As described above in detail, the protrusions 7 having a spacer function in the present invention include the coloring materials (red (R), green (G),
It is formed along with the formation of blue color (B). In a preferred embodiment, it is formed by a so-called transfer method. Therefore, it is possible to omit the conventional process of forming spacers. Further, it is possible to prevent the disturbance of the optical characteristics which has been conventionally generated. Furthermore, the effect that the height of the convex portion having the spacer function can be made uniform can be achieved very easily.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a color filter substrate for a liquid crystal display of the present invention.

FIG. 2A is a plan view showing one step in the manufacturing process of the color filter substrate for a liquid crystal display, and FIG.
FIG. 3 is a cross-sectional view taken along the line aa of FIG.

FIG. 3 (A) is a plan view showing one step in the manufacturing process of the color filter substrate for a liquid crystal display, and FIG.
FIG. 4B is a sectional view taken along the line bb of FIG.

FIG. 4 (A) is a plan view showing one step in the manufacturing process of the color filter substrate for a liquid crystal display, and FIG.
[Fig. 4] is a sectional view taken along the line cc of Fig. 4 (A).

FIG. 5 is a plan view showing a step in the manufacturing process of the color filter substrate for a liquid crystal display.

FIG. 6 is a plan view showing a step in the manufacturing process of the color filter substrate for a liquid crystal display.

FIG. 7 is a plan view showing a step in the manufacturing process of the color filter substrate for a liquid crystal display.

FIG. 8 is a cross-sectional view of a substrate when a color filter layer is formed.

FIG. 9 is a typical basic layout of a color filter.

[Explanation of symbols]

 1 ... Color filter substrate for liquid crystal display 7 ... Convex part 11 ... Transparent substrate 21 ... Black matrix 41, 41a ... Transparent conductive film layer R, G, B ... Color filter layer (coloring material) R ', G', B '... Convex piece (coloring material (piece))

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ken Sasaki 1-1-1, Ichigayakamachi, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd.

Claims (3)

[Claims] 1. A color filter substrate for a liquid crystal display, comprising: a transparent substrate; a color filter layer formed on the transparent substrate to form a pixel; and a transparent conductive film formed on the color filter layer. The color filter layer is a pixel made of each coloring material,
A color filter substrate for a liquid crystal display, comprising a plurality of convex portions having a substantially uniform height formed by partially laminating coloring materials of at least three colors. 2. The convex portion having a substantially uniform height according to claim 1, wherein a transfer film in which a coloring material is formed on the base material in advance is superposed on a transparent substrate, and then the base material is peeled off for coloring. Repeat the transfer operation to transfer the material onto the transparent substrate,
A method for manufacturing a color filter substrate for a liquid crystal display, which is formed by stacking colored materials of at least three colors. 3. The color filter substrate for a liquid crystal display according to claim 1 and a substrate having a plurality of electrodes are bonded to each other through a protrusion having a substantially uniform height formed on the color filter substrate for a liquid crystal display, A liquid crystal display, wherein a liquid crystal material is enclosed in a gap formed by the convex portion.