1. Field of the Invention
The present invention relates to liquid crystal display (LCD) devices, and more particularly to an IPS-LCD (in-plane switching LCD) device having substrates thereof strongly combined together.
2. Description of Prior Art
An LCD panel generally comprises two glass substrates, a peripheral sealant, and a multiplicity of liquid crystal molecules. The sealant is used for adhering the glass substrates together and thus forming a space therebetween. The liquid crystal molecules are filled in the space.
In a color LCD panel, a color filter layer is provided in one of the substrates, which is called a color filter substrate. A conventional method of fabricating a color filter substrate mainly includes the following steps: first, forming a black matrix made of metallic chromium (Cr) or an acrylic resin on a base substrate, the black matrix defining a plurality of holes arranged in an array; next, filling three primary color resists of R (red), G (green), and B (blue) in the holes in a regular, repeating pattern so as to form a color layer; and finally, forming an over coat layer to cover the color layer and the black matrix, the over coat layer being made of an acrylic resin or an epoxy resin or like material. The color filter substrate is thus obtained.
As shown in
The color filter substrate 10 of the IPS-LCD device 1 includes a transparent plate 11, a black matrix 12 defining a plurality of holes (not labeled), a color layer 13 filled in the holes, and an over coat layer 14 covering the black matrix 12 and the color layer 13. Further, an alignment layer 15 is formed on the over coat layer 14, facing the TFT substrate 20.
A peripheral sealant 17 interconnecting the substrates 10, 20 is directly adhered to a peripheral portion of the over coat layer 14 (instead of being directly adhered to the color filter substrate 10). With this configuration, an unused outermost peripheral portion of the transparent plate 11 and thus the color filter substrate 10 can be reduced in size, while still preserving the same area of the color filter substrate 10 that contributes to the displayed image. That is, the utilization of the areas of the substrates 10, 20 of the IPS-LCD device 1 is improved. To put it another way, the total space required for mounting of the IPS-LCD device 1 in any particular apparatus is reduced.
The sealant 17 and the over coat layer 14 are both made of a resin material or a like material. The resin material has good flatness. That is, the roughness of the sealant 17 and the over coat layer 14 is low. Accordingly, when the sealant 17 cures and combines the substrates 10, 20 together, an adhesive strength between the sealant 17 and the over coat layer 14 is poor. The sealant 17 is liable to peel off, which weakens the connection between the combined substrates 10, 20.
It is desired to provide an improved IPS type LCD device which overcomes the above-described deficiencies.
An object of the present invention is to provide an IPS-LCD device having substrates thereof strongly combined together.
In order to achieve the object set out above, an LCD device in accordance with the present invention includes a first substrate having an over coat layer, a second substrate parallel to and spaced apart from the first substrate, a liquid crystal layer having liquid crystal molecules interposed between the substrates, and a sealant disposed between the substrates for sealing a space therebetween. The over coat layer faces the second substrate, and defines a sealing region having a plurality of holes. The sealant interlocks with the sealing region in the holes.
In assembly, the sealant is in liquid form. Part of the sealant permeates into the holes of the sealing region, and fittingly interlocks with the sealing region while curing. Thus the substrates are strongly combined together, and the IPS-LCD is sturdy and durable.
Other objects, advantages, and novel features of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
Reference will now be made to the drawings to describe the present invention in detail.
Referring to
An electrode layer 39 containing a plurality of electrodes (not shown) is formed on the second substrate 40, for generating an electric field to drive the liquid crystal molecules.
The first substrate 30 of the IPS-LCD device 3 includes a transparent plate 31, a black matrix 32, a color layer 33, and an over coat layer 34 covering the black matrix 32 and the color layer 33. Further, an alignment layer 35 is formed on an underside of the over coat layer 34, facing the second substrate 40.
The black matrix 32 is made of an acrylic resin, and is arranged in a regular pattern on the transparent plate 31. The black matrix 32 defines a regular array of holes (not labeled) therein. Three primary color resists of R (red), G (green), and B (blue) are filled in the holes in a regular, repeating pattern, thereby forming the color layer 33.
The over coat layer 34 covers the black matrix 32 and the color layer 33, for eliminating the difference in height between the black matrix 32 and the color layer 33. The over coat layer 34 is made of an acrylic resin, an epoxy resin, or a like material. Also referring to
The sealant 37 adheres to the substrate 30 at the sealing region 341. During the fabricating process, in an initial step, the sealant 37 is discharged on a peripheral portion of an inner surface of the electrode layer 39. In the next step, top parts of the sealant 37 permeate into the holes 342. These parts of the sealant 37 fill the holes 342, and cross link in the sealing region 341 while curing. Referring to
Many modifications and variations are possible within the ambit of the invention herein. For example, the holes 342 of the sealing region 341 can be cylindrical, rhombic-shaped, or have another suitable regular or irregular shape.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set out in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
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93104242 | Feb 2004 | TW | national |