JPH06130218A - Color filter and liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide the color filter with which a beautiful display screen free from unequalnes is obtd. and the liquid crystal display device. CONSTITUTION:Plural colored layers 3 are formed on a light transparent substrate 1 and further, striped photosensitive resists 2 are provided between these colored layers 3. These resists 2 are formed to the thickness equal to the thickness of the colored layers 3. This liquid crystal display device has the first substrate 1, a second substrate which is disposed to face the first substrate 1 via a prescribed spacing and having at least the electrode and the black matrix 9 on the opposite side and a liquid crystal 12 clamped in this spacing. The first substrate is the color filter 4 and the resists 2 of the color filter 4 exist in the positions corresponding to the positions of the black matrix 9. The width of the resists 2 is narrower than the width of the black matrix 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used in a liquid crystal display device capable of full color display and a liquid crystal display device using the color filter.

[0002]

2. Description of the Related Art Generally, liquid crystal display devices are used for displays such as portable computers and word processors, and flat-screen televisions. In recent years, full-color display devices have been introduced. The demand for full-color liquid crystal display devices is rapidly growing, and along with this, the price reduction, large area, and high quality of liquid crystal display devices are being promoted.

By the way, an active matrix type full color liquid crystal display device using a thin film transistor, which is one type of active matrix type driving system, has a transparent substrate provided with individual electrodes inside and a transparent protection inside a color filter. Liquid crystal is filled between the film, the transparent electrode, and the alignment film, which are sequentially stacked. Further, polarizing plates are arranged outside the transparent substrate and the color filter, respectively.

In the above color filter, a light blocking layer having a predetermined pattern, that is, a black matrix is provided on a transparent substrate, and R, G, and B, which become pixel portions, are provided in the gaps of the black matrix. A transparent colored layer is formed.

[0005]

A printing method is one of the methods for manufacturing the conventional color filter as described above. This printing method is a method of printing a colored ink dispersed in a pigment and a resin solvent in a predetermined pattern on the surface of a transparent substrate such as glass, and is a manufacturing method with low cost and high mass productivity. .

That is, in this printing method, R, G, and B color inks are printed in a desired pattern on a transparent substrate by an intaglio offset printing machine equipped with a pressure transfer blanket. At this time, the colored ink coating film has an arcuate surface in the pixel of each color due to viscosity. That is, the film thickness is minimum near the boundary of each colored ink coating film and is maximum in the central portion.

Further, here, in order to smooth such a colored ink film surface, polishing with a wrapping film and heating / pressurizing with a rubber or a mirror-finished metallic roller are performed. This improves the flatness, but may cause waviness at the edges, which may cause unevenness.

By the way, in recent years, further improvement of the aperture ratio is desired due to the demand for power saving and weight saving of the set. As a structure of a liquid crystal device corresponding to this, a light shielding film (hereinafter,
By placing a black matrix)
A method has been proposed in which the line width of the black matrix is made narrower to increase the aperture ratio. In this case, if the line width of the black matrix on the array substrate side is dμm, it must be considered that the colored layer of the color filter is formed as a virtual black matrix of substantially (d−α) μm. here,
α is the accuracy of alignment between the array substrate and the color filter. The cell assembly accuracy, the black matrix pattern on the array substrate side and the colored layer / pattern on the color filter side.
This is a value determined by the total pitch difference of the black matrix and the line width accuracy of the black matrix. According to the calculation by the inventor, when the diagonal size of the liquid crystal module is β inches, α is in the range of 0.39β−0.56 ≦ α ≦ 0.39β + 9.44.

In the manufacture of the color filter, the accuracy of alignment with the array substrate is required to be higher than ever, but when the colored layer is formed by the printing method, unevenness is a serious problem due to the above reasons. Is becoming.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a color filter and a liquid crystal display device capable of obtaining a beautiful display screen without unevenness.

[0011]

According to the present invention, a plurality of colored layers are formed on a light transmissive substrate, and a stripe-shaped photosensitive resist is provided between the colored layers. Color that is as thick as the colored layer
It is a filter.

The present invention also provides a first substrate and the first substrate.
A second substrate, which is arranged to face the substrate of FIG. 2 through a predetermined gap and has at least an electrode and a black matrix on the facing surface side, and a liquid crystal held in the gap, and the first substrate is the above-mentioned color substrate. A filter, the resist of this color filter is at a position corresponding to the position of the black matrix, and the width of this resist is a liquid crystal display device narrower than the width of the black matrix.

[0013]

According to the present invention, the arc-shaped colored layer can be flattened without causing undulations at the ends, and a color filter having no unevenness can be obtained. The color filter is used in a liquid crystal display device. In this case, it is possible to prevent the occurrence of defects after cell assembly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

The color filter according to the present invention is shown in FIG.
The transparent colored layers 3 of red (R), green (G), and blue (B), which are configured as shown in (d) and serve as a plurality of pixel portions, are arranged at predetermined intervals on the transparent substrate 1 which is a light-transmissive substrate. Is formed by.
A stripe-shaped photosensitive resist 2 is provided between each colored layer 3, and the thickness of the resist 2 is set to be equal to the thickness of the colored layer 3.

Next, a method of manufacturing this color filter will be described. The color filter is constructed as shown in FIGS. 1A to 1D, and as shown in FIG. A photosensitive resist 2 is applied onto a transparent substrate 1 made of a material such as spin coater or roll coater. At this time, the film thickness of the photosensitive resist 2 is 2 ± 0.3 when the film thickness of the colored layer formed later is 2 μm before the flattening process.
μm is desirable.

Next, ultraviolet rays are radiated from above a photomask (not shown), and a plurality of stripe-shaped photosensitive resists 2 are formed at predetermined intervals in a pattern as shown in FIG. 2B by a crosslinking reaction. To do. The width of the photosensitive resist 2 at this time is narrower than the width of the black matrix on the array substrate side in the liquid crystal display device described later. In this embodiment, the width of the black matrix is set to 15 μm with respect to 30 μm, and the interval between the adjacent photosensitive resists 2 is 50 μm, which is the same as the width of the colored layer (not shown) 50 μm before the flattening process.
It is set to m.

Next, as shown in FIG. 2C, the red (R), green (G), and blue (B) colored layers 3 are formed by an intaglio offset printing machine equipped with a pressure transfer blanket. Form. This figure (c) is a state before the flattening process, and has a substantially arc-shaped cross section. At this time, the photosensitive resist 2
Of the colored layer 3 before the flattening treatment is ± 0.
It is set in the range of 3 μm. The ink in the colored layer 3 is solidified by baking every time printing of each color is completed.

Next, when a flattening process is performed using, for example, a wrapping film (not shown), it is flattened as shown in FIG. At this time, the stripe-shaped photosensitive resist 2 plays a role of preventing the undulation of the end portion of the colored layer 3. However, at this point, there is a portion where the colored layer 3 partially protrudes into the adjacent color portion due to the variation in the width of the colored layer 3. Therefore, polishing is performed thereafter. As a result, the protruding portion of the colored layer 3 could be removed as shown in FIG. Finally, a color filter is obtained by forming a transparent electrode (not shown) into a film of about 1000 angstrom by the sputtering method.

Next, a liquid crystal display device employing the color filter of the present invention will be described. That is, the liquid crystal display device according to the present invention is constructed as shown in FIG. 2, the reference numeral 4 in the drawing is the color filter described above, and the same portions as those in FIG. 1 are designated by the same reference numerals. Then, on the color filter 4, a transparent electrode 5 made of ITO (indium-tin oxide) or the like and an alignment film 6 are sequentially laminated.

On the other hand, an array substrate 7 having thin film transistors (not shown) is arranged facing the color filter 4 at a predetermined interval, and a gate insulating film 8 is provided on the array substrate 7.
Are formed. A color is formed on the gate insulating film 8.
A black matrix 9 is formed on the filter 4 at a position corresponding to the photosensitive resist 2. Further, a transparent electrode 10 made of ITO or the like and an alignment film 11 are sequentially laminated so as to cover the gate insulating film 8 and the black matrix 9. A liquid crystal 12 is filled between the array substrate 7 and the color filter 4. Further, polarizing plates 13 and 14 are arranged outside the array substrate 7 and the color filter 4, respectively. Structures such as thin film transistors and data lines are omitted. In the above case, cell alignment error, black matrix 9 and colored layer 3
In order to have a margin of 7.5 μm on one side in consideration of the total pitch difference and the line width accuracy of the black matrix 9,
The width of the black matrix 9 is 30 μm, and the width of the photosensitive resist 2 is 15 μm. Therefore, even if a single color raster display is performed as a liquid crystal module, a beautiful display screen without unevenness can be obtained.

According to the above-described color filter manufacturing method, even in the printing method, as a black matrix on array type thin film transistor liquid crystal display device,
An even color filter can be obtained. In particular,
By making the pattern interval of the resist 2 wider than the width of the colored layer 3 before the flattening treatment, the colored layer 3 can be formed between the resist patterns without fail. Further, the film thickness of the resist 2 is ±± with respect to the film thickness of the colored layer 3 before the flattening process.
By setting the thickness to 0.3 μm, it becomes possible to flatten the arc-shaped pixel by the flattening process thereafter without causing the undulation of the end portion. Further, the width of the resist 2 is set to the width dμm of the black matrix 9 in consideration of the alignment accuracy of the array substrate 7 and the color filter 4 (d−α) μ.
By setting m, it is possible to prevent the occurrence of defects after cell assembly. However, α is in the range of 0.39β−0.56 ≦ α ≦ 0.39β + 9.44 when the diagonal size of the liquid crystal module is β inches.

[0023]

According to the present invention, it is possible to flatten an arcuate colored layer without causing undulations at the ends.
A color filter having no unevenness can be obtained, and when this color filter is used in a liquid crystal display device, it is possible to prevent the occurrence of defects after cell assembly.

[Brief description of drawings]

1A to 1D are process explanatory views showing a manufacturing method of a color filter according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a liquid crystal display device according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate (light transmissive substrate), 2 ... Resist, 3 ... Colored layer, 4 ... Color filter, 5, 10 ... Transparent electrode, 6,
11 ... Alignment film, 7 ... Array substrate, 8 ... Gate insulating film, 9
... black matrix, 12 ... liquid crystal, polarizing plates 13 and 14
…Polarizer.

Claims (2)

[Claims] 1. A color filter comprising a plurality of colored layers formed on a light transmissive substrate, wherein a stripe-shaped photosensitive resist is provided between the colored layers, and the thickness of the resist is the thickness of the colored layers. A color filter having the same thickness as that of the color filter. 2. A first substrate, a second substrate facing the first substrate with a predetermined gap therebetween and having at least an electrode and a black matrix on the facing surface side, and sandwiched between the first substrate and the second substrate. In the liquid crystal display device including the liquid crystal, the first substrate is the color filter according to claim 1, the resist is at a position corresponding to the position of the black matrix, and the width of the resist is A liquid crystal display device characterized by being narrower than the width of the black matrix.