Liquid crystal panel and method of fabricating the same

• US 6,989,879 B1
• Filed: 08/11/1999
• Issued: 01/24/2006
• Est. Priority Date: 08/31/1998
• Status: Expired due to Term

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Hagiwara, Takeshi, Uehara, Hideki, Miyazaki, Takashi, Nakahara, Hiroki
• Primary Examiner(s): Nguyen, Dung T.
• Assistant Examiner(s): QI, ZHI QIANG
• Application Number:
  US09/530,122
• Time in Patent Office: 2,358 Days
• Field of Search: 349/123, 349/124, 349/153, 349/190, 349/149
• US Class Current: 349/123
• CPC Class Codes: G02F 1/1337 Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells

Abstract

In a liquid crystal panel 1 provided with first and second substrates 1 and 3 bonded by a sealant 3, alignment layers 13 and 23 for covering electrodes 6A and 7A, respectively, are formed up to the regions overlapping the regions for forming up to 3. Accordingly, since there is no space between the alignment 13 or 23 and the sealant 3, a low twist domain does not occur in a liquid crystal 40. Therefore, the vicinity of the inner periphery of the sealant can also be effectively used as the region for displaying images.

Claims

1. A liquid crystal panel comprising:

a pair of substrates bonded to each other by a sealant;

a liquid crystal enclosed in an inner region delimited by the sealant between the pair of substrates;

first electrodes formed on an inner side of a first substrate of the pair of the substrates;

second electrodes formed on an inner side of a second substrate of the pair of substrates;

terminals formed on the inner side of each of the pair of substrates for conducting between the substrates, the terminals being arranged in a sealant region on which the sealant is formed and connected through a conductive particle included in the sealant; and

a first alignment layer formed on the first electrodes and covering the inner region delimited by the sealant;

a second alignment layer formed on the second electrode and covering the inner region delimited by the sealant;

wherein the first alignment layer and the second alignment layer are formed from the inner region to the sealant region, the first and second alignment layers partially overlapping the sealant region on which the sealant is formed along a side of the sealant provided with the terminals such that an edge of the first and second alignment layers terminates in the sealant region; and

another edge of the first second alignment layers crosses over the sealant region to an outer side of the sealant along a side of the sealant other than the side provided with the terminals.

2. A liquid crystal panel according to claim 1, wherein the sealant is a one-part thermosetting epoxy sealant.

3. A liquid crystal panel according to claim 1, wherein the first and second alignment layers are formed up to a region overlapping the region for forming the sealant in the sections corresponding to the four sides of the substrate.

4. A liquid crystal panel according to claim 1, wherein the first and second alignment layers are formed up to edges of the substrates across the region for forming the sealant in the individual sides of the substrate excluding the sides provided with input-output terminals and the terminals for conducting between the substrates.

5. A liquid crystal panel according to claim 1, wherein the first and second alignment layers are formed up to edges of the substrates across the region for forming the sealant in the individual sides of the substrates excluding the side provided with the input-output terminals for conducting between the substrates.

6. A method of fabricating a liquid crystal panel defined in claim 1, wherein the first and second electrodes are formed on the surface of a large substrate for forming a plurality of pairs of substrates in individual regions for forming the substrates which are divided by cutting the large substrate along cutting projection lines, and then thin films for forming the first and second alignment layers are formed inside the region delimited by the sealant, and the first and second alignment layers are also formed to partially overlap the sealant in a region for conducting between the substrates and to cross the regions for forming the sealant in a region other than the region for conducting between the substrates.

7. A method of fabricating a liquid crystal panel according to claim 6, wherein the first and second electrodes are formed on the surface of the large substrate for forming a plurality of pairs of substrates in the individual regions for forming the substrates which are divided by cutting the large substrate along cutting projection lines, and then the films for forming the first and second alignment layers are formed on a plurality of substrate forming-regions including the cutting projection lines.

8. A method of fabricating a liquid crystal panel according to claim 7, wherein the first and second electrodes are formed on the surfaces of a pair of large substrates for forming a plurality of pairs of substrates in the regions for forming the individual substrates which are divided by cutting the large substrates along cutting projection lines, the thin films for forming the first and second alignment layers are formed on the plurality of substrate forming-regions including the cutting projection lines in each of the pair of large substrates, the sealant is formed on at least one of the pair of large substrates to bond the large substrates to each other, and the bonded large substrates are cut along the cutting projection lines.

9. A method of fabricating a liquid crystal panel according to claim 7, wherein, in the large substrate, the substrate forming regions are placed with a cutting projection line therebetween so that the sides provided with input-output terminals and terminals for conducting between substrates are directed in the opposite directions, and when the thin films for forming the first and second alignment layers are formed, the thin films are formed in stripes along the cutting projection line.

10. The liquid crystal panel according to claim 1, further comprising a transparent insulation film formed on the first and second electrodes so as to cover the inner region delimited by the sealant;

wherein the first and second alignment layers are formed on the transparent insulation film, and the transparent insulation film and the first and second alignment layers are formed from the inner region to an intermediate portion of the sealant region on which the sealant is formed, along a side of the sealant provided with the terminals; and

the transparent insulation film and the second alignment layer cross over the sealant region to an outer side of the sealant, along a side of the sealant other than the side provided with the terminals.

11. A liquid crystal panel comprising:

a first substrate;

first electrodes formed on said first substrate;

a first alignment layer formed over said first electrodes;

a second substrate;

second electrodes formed on said second substrate;

a second alignment layer formed over said second electrodes;

a sealant formed in a sealant region, the sealant coupled between said first and second substrates so as to form a gap therebetween;

terminals formed on an said first and second substrates for conducting between said first and second electrodes, the terminals being arranged in the sealant region and connected through a conductive particle included in the sealant;

wherein each of said first and second alignment layers is formed on and covers an inner region delimited by the sealant;

the first and second alignment layers are formed from the inner region to the sealant region, the first and second alignment layers partially overlapping the sealant region where the sealant is formed along a side of the sealant provided with the terminals such that an edge of the first and second alignment layers terminates in the sealant region; and

another edge of the first and second alignment layers crosses over the sealant region to an outer side of the sealant along a side of the sealant other than the side provided with the terminals.

12. The liquid crystal panel of claim 11, wherein said first alignment layer is interposed between said sealant and said first substrate.

13. The liquid crystal panel of claim 11, wherein said second alignment layer is interposed between said sealant and said second substrate.

14. The liquid crystal panel of claim 11, wherein said first alignment layer extends to a perimeter of said first substrate.

15. The liquid crystal panel of claim 11, wherein said second alignment layer extends to a perimeter of said second substrate.

16. The liquid crystal panel of claim 11, wherein said side provided with said terminals for conducting between said first and second substrates includes input-output terminals.

17. The liquid crystal panel of claim 11, further comprising:

a first transparent insulation film interposed between said first alignment layer and said first substrate over said first electrodes; and

a second transparent insulation film interposed between said second alignment layer and said second substrate over said second electrodes, said first and second transparent insulation films complementing a configuration of said first and second alignment layers.

18. A method of fabricating a liquid crystal panel comprising:

providing a pair of large substrates including a plurality of smaller substrate forming regions divided by a plurality of cutting lines, the liquid crystal panel fabricated by using each of the substrate forming regions;

forming first electrodes on an inner side of a first substrate of the pair of large substrates;

forming second electrodes on an inner side of a second substrate of the pair of large substrates;

forming terminals on each of the smaller substrate forming regions on the inner side of each of the pair of large substrates for conducting between the substrates, the terminals being arranged in a sealant region on which a sealant is formed, the terminals being connected through a conductive particle included in the sealant, the sealant bonding the pair of large substrates for every smaller substrate forming region; and

forming a first alignment layer on the first electrodes that cover an inner region delimited by the sealant;

forming a second alignment layer on the second electrodes that cover an inner region delimited by the sealant;

wherein the first and second alignment layers are formed from the inner region to the sealant region on which the sealant is formed, the first and second alignment layers partially overlapping the sealant region along a side of the sealant provided with the terminals such that an edge of the first and second alignment layers terminates in the sealant region; and

another edge of the first and second alignment layers crosses over the sealant region to an outer side of the sealant along a side of the sealant other than the side provided with the terminals.

19. The method of claim 18, wherein said alignment layers are deposited so as to overlap said sealant region along each of said smaller substrate forming regions.

20. The method of claim 18, wherein said alignment layers are deposited so as to overlap said plurality of projected cutting lines.

21. The method of claim 18, further comprising depositing a sealant on said sealant region of each of said smaller substrate forming regions.

22. The method of claim 21, further comprising:

bonding the pair of large substrates by securing said sealant to said sealant region along each of said smaller substrate forming regions on said substrates; and

cutting said pair of substrates along said cutting lines.

23. The method of claim 18, further comprising a step of forming a transparent insulation film on the first and second electrodes so as to cover the inner region delimited by the sealant;

wherein the first and second alignment layers are formed on the transparent insulation film, and the transparent insulation film and the first and second alignment layers are formed from the inner region to an intermediate portion of the sealant region on which a sealant is formed, along a side of the sealant provided with the terminals; and

the transparent insulation film and the second alignment layer cross over the sealant region to an outer side of the sealant, along a side of the sealant other than the side provided with the terminals.

24. A liquid crystal panel comprising:

a pair of substrates bonded to each other by a sealant with a predetermined gap therebetween;

a liquid crystal enclosed in a region delimited by the sealant between the pair of substrates;

first electrodes formed on an inner side of a first substrate of the pair of the substrates for controlling an alignment state of the liquid crystal;

second electrodes formed on an inner side of a second substrate of the pair of the substrates for controlling the alignment state of the liquid crystal;

terminals formed on the inner side of each of the pair of substrates for conducting between the substrates, the terminals being arranged in a sealant region on which the sealant is formed, and the terminals being connected through a conductive particle included in the sealant; and

a first alignment layer formed on the first electrodes and covering the inner region delimited by the sealant;

a second alignment layer formed on the second electrodes and covering the inner region delimited by the sealant;

wherein the first and second alignment layers are formed from the inner region to the sealant region, and partially overlap the sealant region along a side of the sealant provided with the terminals such that an edge of the first and second alignment layers terminates in the sealant region; and

another edge of the first and second alignment layers crosses over the sealant region to an outer side of the sealant along a side of the sealant other than the side provided with the terminals.

25. A liquid crystal panel comprising:

a first substrate;

first electrodes formed on an inner side of said first substrate;

a first alignment layer formed on said first electrodes;

a second substrate;

second electrodes formed on an inner side said second substrate;

a second alignment layer formed on said second electrodes; and

terminals formed on the inner side of said first and second substrates for conducting between said first and second electrodes, the terminals being arranged in a sealant region on which a sealant is formed and connected through a conductive particle included in a sealant;

wherein the sealant is coupled between said first and second substrates so as to form a gap therebetween;

each of said first and second alignment layers are formed inside of and covers an inner region delimited by the sealant;

said first and second alignment layers are formed from the inner region to the sealant region and partially overlap the sealant region such that an edge of said first and second alignment layers terminates in the sealant region along a side of the sealant provided with the terminals; and

another edge of said first and second alignment layers crosses the sealant region to an outer side of the sealant along a side of the sealant other than the side provided with said terminals.