JP2017040678A - Color filter - Google Patents

Abstract

A color filter formed by coating a plurality of pixels with a transparent overcoat resin layer in common and filling the white pixels with the overcoat resin layer to reduce recesses of the overcoat resin layer on the white pixels. Colored pixels filled with a colored resist and white pixels are regularly assigned to rectangular openings of a grid-like first black matrix, and the rectangular openings to which the white pixels are assigned are formed at their edges. forming a second black matrix pattern in which portions are connected to the first black matrix, forming the colored pixels, and then covering the colored pixels and the white pixels with a transparent overcoat resin layer in common; to manufacture a color filter in which the white pixels are filled with the overcoat resin layer. [Selection drawing] Fig. 1

Description

  The present invention relates to a color filter used in a flat color display device such as a liquid crystal display device or an organic EL display device.

  A flat color display device, such as a liquid crystal display device, is configured by injecting liquid crystal into a gap between an opposing TFT substrate and a color filter substrate (hereinafter referred to as a color filter) and bonding the substrates together with a sealant. . The color filter is a member necessary for color display of the liquid crystal display device, and generally has three color pixels of red, green, and blue pixels finely patterned.

  In recent years, four color filters have been proposed as a method for improving the transmittance of a flat color display device such as a liquid crystal display device. For example, Patent Document 1 proposes a four-color filter substrate having white pixels in addition to red, green, and blue pixels. The white pixel contains no colorant and is transparent, and the white light from the light source is used as it is to make the display image look bright.

  Moreover, in patent document 1, after forming the red color pixel R, the green color pixel G, and the blue color pixel B for the color filter which has a white pixel, the space which a white pixel should occupy is transparent overcoat which also serves as a white pixel There has been proposed a technique of filling the resin layer by batch formation.

JP 11-295717 A

  However, when the white pixels are filled by batch formation of the overcoat resin layer, there is a problem that a depression is generated in the overcoat resin layer on the white pixels. When the color filter having the dent is incorporated in a display device, there is a problem that the distance from the array substrate is not constant and the display characteristics are deteriorated.

  An object of the present invention is to solve the above problems and to obtain a color filter in which a dent generated in an overcoat resin layer on a white pixel is reduced.

  In order to solve the above problems, the present invention provides a color formed by regularly assigning colored pixels and white pixels filled with a colored resist to rectangular openings of a grid-like first black matrix for color display. A second black matrix pattern having an end connected to the first black matrix is formed in a rectangular opening to which the white pixel is assigned, and the coloring pixel is formed. The color filter is characterized in that the white pixel is filled with the overcoat resin layer by commonly covering the pixel and the white pixel with a transparent overcoat resin layer.

  With this configuration, the present invention has an effect of reducing the amount of dent in the white pixel region of the overcoat resin layer.

  Further, the present invention is the color filter described above, wherein the area of the second black matrix pattern formed in the rectangular opening to which the white pixel is assigned is 10 minutes of the area of the rectangular opening to which the white pixel is assigned. The color filter has an area of 1 or less and 1/50 or more.

  Further, the present invention is the color filter according to the above-described color filter, wherein the amount of depression of the overcoat resin layer on the white pixel is not more than one tenth of the thickness of the overcoat resin layer. is there.

  According to the present invention, the second black matrix pattern is formed in the area to which the white pixel is allocated, thereby reducing the amount of depression in the white pixel area of the overcoat resin layer, and the second black matrix pattern is Since the black matrix pattern is connected to one black matrix pattern, there is an effect that the black matrix pattern is peeled off during the process and remains on the color filter to cause a foreign matter defect.

It is a partial enlarged plan view of a color filter according to an embodiment of the present invention. It is a partial expanded side sectional view explaining the manufacturing method of the color filter of embodiment of this invention.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a partially enlarged plan view of a color filter 10 of this embodiment, and FIG. 2 is a partially enlarged side sectional view for explaining a method for manufacturing the color filter 10 of this embodiment.

  As shown in the plan view of FIG. 1, the color filter 10 includes a first black matrix 2 in a lattice shape, and a first colored pixel R (red) and a second color in a rectangular opening of the first black matrix 2. The colored pixels G (green), the third colored pixels B (blue), and the white pixels W are regularly arranged.

  Further, as shown in FIG. 1, when forming the first black matrix 2 in the form of a lattice, at the same time, the second black matrix in the form of a thin line is formed in the rectangular opening of the first black matrix 2 to which the white pixels W are assigned. Pattern 2B is formed.

  The second black matrix pattern 2B formed in the rectangular opening to which the white pixel W is assigned is preferably formed as a cross-shaped thin line pattern as shown in FIG. The reason is that the strength of the second black matrix pattern 2B is increased by forming the connected thin line pattern, and the strength is also strong against stress from the lateral direction of the fine line by forming the cross pattern. It is because it can strengthen.

  The area of the second black matrix pattern 2B formed in the white pixel W is preferably not more than one-tenth of the area of the white pixel W region and not less than one-fifth. If the area of the second black matrix pattern 2B is larger than one-tenth of the area of the white pixel W region, the effect of improving the brightness by the white pixel W is reduced and darkened.

  On the other hand, when the area of the second black matrix pattern 2B is less than 1/50 of the area of the white pixel W region, the dent amount of the overcoat resin layer 3 is 10 minutes of the film thickness of the overcoat resin layer 3. 1 will be exceeded.

  By forming the second black matrix pattern 2B, when the overcoat resin layer 3 is filled in the white pixel W as shown in FIG. 2D, the amount of depression on the white pixel W in the overcoat resin layer 3 There is an effect that can be reduced.

  In the rectangular openings partitioned by the grid pattern of the first black matrix 2, the first colored pixels R, the second colored pixels G, and the first colored pixels R are formed in rectangular openings other than the rectangular openings for the white pixels W. 3 colored pixels B are uniformly filled with colored transparent resin materials having respective hues.

  Then, the colored pixels and the entire surface of the white pixels W that are not yet filled with the colored transparent resin material are commonly covered with the transparent overcoat resin layer 3. The overcoat resin layer 3 also serves as a colored pixel pattern that fills the area of the white pixel W.

(Color filter manufacturing method)
A method for manufacturing the color filter 10 according to the first embodiment of the present invention will be described with reference to the partially enlarged side sectional views of FIGS.

(Process 1)
First, as shown in FIG. 2A, a first black matrix 2 that defines a rectangular opening corresponding to a pixel portion is formed on a transparent substrate 1 for transparent color filters such as glass. The width of the first black matrix 2 is preferably in the range of 3 to 30 μm.

  The first black matrix 2 is formed by applying a black photosensitive resin composition to the color filter transparent substrate 1 and drying it to form a black photosensitive resin layer.

  Next, the black photosensitive resin layer is exposed using a photomask having a predetermined pattern. Next, the pattern of the first black matrix 2 is cured by developing with a developer such as an aqueous solution of sodium carbonate, drying, and then performing a heat treatment.

  In this way, on the color filter transparent substrate 1, a pattern of a rectangular opening surrounded by a frame-shaped outer periphery light-shielding portion that demarcates a display area and a lattice-shaped light-shielding portion provided continuously to the outer periphery light-shielding portion is provided. A first black matrix 2 is formed.

  Next, a transparent material colored with a photosensitive hue at a predesigned position of the rectangular opening of the first black matrix 2 is photolithographically applied to the first colored pixel R, the second colored pixel G, the second colored pixel G, and the like. 3 patterns of colored pixels B are formed.

(Step 2) Formation of First Colored Pixel R First, as shown in FIG. 2B, a photosensitive material in which a red pigment is dispersed in a predetermined rectangular opening of the first black matrix 2 as follows. A pigment-dispersed transparent resin composed of a resin composition is applied to the transparent substrate for color filter 1 and dried to form a red photosensitive pigment-dispersed transparent resin layer.

  A first colored pixel R is formed in a predetermined rectangular opening of the first black matrix 2 by a photolithography method in which a photomask pattern is exposed and developed on the pigment-dispersed transparent resin layer.

(Step 3) Formation of Second Colored Pixel G Next, by the same photolithography method, as shown in FIG. 2C, the second colored pixel G is formed in a predetermined rectangular opening of the first black matrix 2. Form.

(Step 4) Formation of Third Colored Pixel B Next, the third colored pixel B is formed by the same photolithography method. As a result, a color filter layer formed of RGB colored pixels is formed on the transparent substrate 1 as shown in the plan view of FIG.

(Process 5)
Next, as shown in FIG. 2D, a transparent overcoat resin layer 3 (flattened) is formed on the entire surface of the color filter layer formed of RGB colored pixels and the white pixels W not yet filled with the colored transparent resin material. Layer).

  At that time, the region of the white pixel W is filled with the overcoat resin layer 3. That is, the overcoat resin layer 3 also serves as a filling material for a colored pixel that fills the region of the white pixel W.

  The amount of depression of the overcoat resin layer 3 in the white pixel W is desirably 1/10 or less of the film thickness of the overcoat resin layer 3. That is, if the amount of depression of the overcoat resin layer 3 in the white pixel W is 1/10 or less of the film thickness of the overcoat resin layer 3, the flatness as the color filter 10 is maintained at a certain level or more. This is desirable because the influence on the display quality of the liquid crystal display cell incorporating the color filter 10 is reduced.

  Here, since the second black matrix pattern 2B is formed in the area of the white pixel W as shown in FIG. 1 and FIG. 2D, it occurs on the surface of the overcoat resin layer 3 filled in the white pixel W. There is an effect that the amount of dent to be made can be reduced to 1/10 or less of the film thickness of the overcoat resin layer 3.

(Step 6)
Next, a transparent electrode pattern is formed on the overcoat resin layer 3 of the color filter 10. For example, a conductive transparent electrode, specifically, a metal oxide, for example, usually a transparent electrode pattern of ITO is formed by vacuum deposition.

  It should be noted that a flat color display device such as a liquid crystal display device or an organic EL display device can be provided by using the color filter 10 of the present invention. By using the color filter 10 of the present invention that can be easily provided with high quality, the display quality of the flat color display device can be improved.

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... 1st black matrix 2B ... 2nd black matrix pattern 3 ... Overcoat resin layer 10 ... Color filter R ... 1st coloring pixel (red) )
G ... Second colored pixel (green)
B ... Third colored pixel (blue)
W ... White pixel

Claims (3)

  A color filter formed by regularly assigning colored pixels and white pixels filled with a colored resist to rectangular openings of a grid-like first black matrix for color display, wherein the white pixels are assigned In the opening, a second black matrix pattern whose end is connected to the first black matrix is formed, the colored pixels are formed, and the colored pixels and the white pixels are transparent overcoat resin layers The color filter is characterized in that the white pixel is filled with the overcoat resin layer by covering in common.   2. The color filter according to claim 1, wherein an area of the second black matrix pattern formed in the rectangular opening to which the white pixel is assigned is equal to or less than 1/10 of an area of the rectangular opening to which the white pixel is assigned. A color filter having an area of 1/50 or more.   3. The color filter according to claim 1, wherein a dent amount of the overcoat resin layer on the white pixel is not more than one tenth of a film thickness of the overcoat resin layer.

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