JP4202809B2 - Color filter substrate for liquid crystal display elements - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a color filter substrate for a liquid crystal display element, and more particularly to a color filter substrate for a liquid crystal display element in which a reflective layer and a color filter are not peeled off.
[0002]
[Prior art]
Conventionally, a color liquid crystal display element having three color filters of red (R), green (G) and blue (B) has been used for color liquid crystal display. The color filter substrate is formed.
[0003]
The conventional color filter substrate has a transparent substrate formed of glass, plastic or the like. The predetermined area at the center of the transparent substrate is a display area for the color liquid crystal display element, and the outside of the display area is a non-display area. A light diffusion base layer is formed at least in the display region of the transparent substrate. The formation of the light diffusing base layer will be described. A translucent photosensitive resin material is disposed at least on the display area of the transparent substrate, and the surface of the photosensitive resin material is partially removed by a photolithography method to obtain a predetermined interval. In addition, a light diffusion base layer made of a photosensitive resin having a number of corrugated irregularities on the surface is formed by performing heat treatment and the like.
[0004]
Further, a reflective layer or a semi-transmissive reflective layer made of a metal film such as aluminum or silver is formed on the light diffusion base layer. In the display area on the reflective layer or the semi-transmissive reflective layer, a large number of color filters composed of three colors of red, green and blue are formed at predetermined intervals and in an array by an electrodeposition method or the like. In addition, a black mask for light shielding is formed on the reflective layer.
[0005]
Further, on the transparent substrate, a flattening film made of acrylic resin, epoxy resin or the like for the purpose of flattening the display area is formed so as to cover the color filter and the black mask. Is formed with a transparent electrode made of ITO. Furthermore, a color filter substrate is formed by forming an alignment film on the transparent electrode.
[0006]
The color liquid crystal display element has a counter substrate on which transparent electrodes and alignment films are formed at positions facing the color filter of the color filter substrate, and a large number of spacers are scattered on the opposing surfaces of both substrates. Then, it is bonded via a frame-shaped sealing material, and after liquid crystal is injected from an opening formed in the sealing material, the opening is sealed with a sealing material to form a color liquid crystal display element. (See, for example, Patent Document 1).
[0007]
[Patent Document 1]
JP 2001-154204 A (page 3-4, FIG. 1)
[0008]
[Problems to be solved by the invention]
However, in the color filter substrate used in the conventional color liquid crystal display element, the gas generated at the time of forming the light diffusion base layer and the gas generated from the light diffusion base layer by the heat at the time of forming each layer after the light diffusion base layer is formed are stable. In other words, there is a problem that the gas and the color filter formed on the reflective layer may be peeled off by the gas.
[0009]
The present invention has been made in view of such problems, and even when a gas is generated from the light diffusion base layer during the formation of the light diffusion base layer or in a subsequent process, the color filter and the reflective layer stably maintain an adhesive state. An object of the present invention is to provide a color filter substrate that can be made.
[0010]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the color filter substrate according to the present invention is characterized in that a color filter is not formed and an opening is formed in the reflective layer below the black mask.
[0011]
By adopting such a configuration, degassing such as carbon dioxide gas generated from the light diffusion base layer is performed through the opening. Therefore, even if gas is generated from the light diffusion base layer, this gas causes the reflective layer and the color filter to There is no fear of peeling off, and the reflective layer and the color filter can stably maintain the adhesive state. Further, since the opening is formed, the contact area between the reflective layer and the black mask is reduced, so that it is possible to reduce the influence due to the elongation change due to the thermal expansion difference between the reflective layer and the black mask.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a color filter substrate for a liquid crystal display element according to the present invention will be described with reference to the drawings.
[0013]
FIG. 1 is a schematic sectional view showing a configuration of a color filter substrate for a liquid crystal display element according to the present invention, and FIG. 2 is a schematic plan view showing a first embodiment of a color filter substrate for a liquid crystal display element according to the present invention. 3 is a schematic plan view showing a second embodiment of the color filter substrate for a liquid crystal display element according to the present invention.
[0014]
The color filter substrate 2 shown in FIG. 1 has a transparent substrate 3 made of glass, plastic, or the like. A photosensitive resin material such as acrylic is disposed on the transparent substrate 3, and the surface of the photosensitive resin material is covered. A light diffusion base layer in which irregularities having a predetermined interval and size are formed by partial removal by a photolithography method, and a plurality of corrugated irregularities 4a are provided on the surface by subjecting the photosensitive resin material to a heat treatment or the like. 4 is formed.
[0015]
Next, a reflective layer 5 such as a metal film such as aluminum or silver is formed on the light diffusion base layer 4 by sputtering or vapor deposition. In the display area on the reflective layer 5, red, green or blue colored resists are arranged by a spin coat method or the like, and a pattern arrangement such as a stripe arrangement, a mosaic arrangement, a delta arrangement or the like is made by a photolithography method or the like. The color filter 6 is formed. The black mask 7 is formed in the display area on the reflective layer 5 so as to shield between the color filters 6. As shown in FIG. 1, the reflective layer 5 is a portion where the plurality of color filters 6 are not formed and an opening 11 penetrating in the layer pressure direction is reflected in the reflective layer 5 below the black mask 7, for example. A plurality of layers 5 are formed by partially removing the layers 5 by photolithography.
[0016]
The shape of the opening 11 is preferably a slit shape from the viewpoint of appropriately relieving the stress at the interface caused by the difference in thermal expansion coefficient between the reflective layer 5 and the black mask 7, but circular, elliptical, triangular, etc. You may select from the shape and use.
[0017]
In the first embodiment, as shown in FIG. 2, a slit having a width of 10 μm or less is formed in the reflective area 5 below the black mask 7 in the display area where the color filter 6 is not formed. A plurality of shaped openings 11a are formed.
[0018]
Further, in the second embodiment, as shown in FIG. 3, in the display area, the color filter 6 is not formed, and the reflective layer 5 below the black mask 7 has a diameter width of 10 μm or less. A plurality of circular openings 11b are formed.
[0019]
A black mask 7 in which a metal such as chrome or a black resin is patterned by a photolithography method or the like is formed on the reflective layer 5 in which the opening 11b is formed. In the display area on the reflective layer 5, red, green or blue colored resists are arranged by a spin coat method or the like, and a pattern arrangement such as a stripe arrangement, a mosaic arrangement, a delta arrangement or the like is made by a photolithography method or the like. The color filter 6 is formed. The black mask 7 is formed in the display area on the reflective layer 5 so as to shield between the color filters 6.
[0020]
Further, a planarizing film 8 made of, for example, an acrylic resin or an epoxy resin is formed on the black mask 7 and the color filter 6 for the purpose of planarizing the display area. The transparent electrode 9 made of ITO is formed. Furthermore, an alignment film (not shown) is formed on the transparent electrode 9 to constitute the color filter substrate 2 as a whole.
[0021]
Although the black mask 7 disposed in each opening 11 is somewhat concave, there is no possibility of adversely affecting the visibility in the display area.
[0022]
The color filter substrate 2 for a liquid crystal display element of the present embodiment having such a configuration has a gas generated from the light diffusion base layer 4 when the light diffusion base layer 4 is formed through each opening 11 formed in the reflection layer 5. Further, since the gas generated from the light diffusion base layer 4 is released during the subsequent heating, the reflective layer 5 and the color filter 6 are prevented from being peeled off by the generated gas, and the color filter 6 is stably adhered. Can be held. At this time, if each opening 11 is provided to extend to the end face of the reflective layer 5, the gas can be released more favorably. Furthermore, since the opening 11 is provided, the contact area between the reflective layer 5 and the black mask 7 is reduced, so that it is possible to reduce the influence of the elongation change due to the difference in thermal expansion between the reflective layer 5 and the black mask 7.
[0023]
In addition, this invention is not limited to embodiment mentioned above, A various change is possible as needed. For example, although the reflective liquid crystal display element has been described in the present embodiment, the same effect can be obtained even if the reflective liquid crystal display element is used.
[0024]
【The invention's effect】
As described above, according to the present invention, even if gas is generated from the light diffusion base layer during or after the formation of the light diffusion base layer, the gas is released from the opening, so that the reflective layer and the color filter are stably bonded. Can be held. In addition, it is possible to reduce the influence due to the elongation change due to the thermal expansion difference between the reflective layer and the black mask.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing a configuration of a color filter substrate for a liquid crystal display element according to the present invention. FIG. 2 is a schematic plan view showing a first embodiment of a color filter substrate for a color liquid crystal display element according to the present invention. FIG. 3 is a schematic plan view showing a second embodiment of a color filter substrate for a color liquid crystal display element according to the present invention.
2 Color filter substrate 3 Transparent substrate 4 Light diffusion base layer 4a Concavity and convexity 5 Reflective layer 6 Color filter 7 Black mask 8 Flattening film 9 Transparent electrode 11 Opening

Claims (1)

A light diffusing base layer which is formed on a transparent substrate and has a light-transmitting surface and a large number of irregularities on the surface; a reflective layer formed on the light diffusing base layer; a color filter formed on the reflective layer; In a color filter substrate for a liquid crystal display element having a black mask for light shielding formed on a reflective layer,
A color filter substrate for a liquid crystal display element, wherein an opening is formed in a reflective layer below the black mask, which is a portion where the color filter is not formed.

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