Method of manufacturing liquid crystal display panel

• US 6,531,329 B2
• Filed: 06/18/2001
• Issued: 03/11/2003
• Est. Priority Date: 06/20/2000
• Status: Expired due to Term

• Current Assignee: NLT Technologies, Ltd.
• Original Assignee: NEC Corporation
• Inventors: Asakura, Tetsuroh, Sasaki, Takeshi
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): Le, Thao P.
• Application Number:
  US09/885,359
• Publication Number:
  US 20010055827A1
• Time in Patent Office: 631 Days
• Field of Search: 438/30, 257/59, 349/5, 349/153
• US Class Current: 438/30
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: G02F 1/1341 Filling or closing of cells
• CPC Class Codes: G02F 1/13415 Drop filling process

Abstract

Provided is a method of manufacturing a liquid crystal display panel of high quality without wasting liquid crystal material. In a step for pressing both of transparent glass substrates against each other, liquid crystal spreads and air bubbles are exhausted through notch portions. A sealing material is crushed before the liquid crystal reaches the notch portions, and the notch portions are blocked. Accordingly, a gap between the transparent glass substrates is sealed in a state where the liquid crystal is filled therein. Moreover, at the same time, both of the transparent glass substrates are compressively attached to each other with the sealing material interposed therebetween.

Claims

1. A method of manufacturing a liquid crystal display panel in which liquid crystal is held between a pair of panel substrates facing each other, on which an electrode is formed, comprising:

a step for coating a sealing material on a plane of a least one of said panel substrates, on which the electrode is formed, with a predetermined coating pattern having a notch portion comprising a break between a first portion of said sealing material and a second portion of said sealing material;

a step for dropping the liquid crystal on said plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined dropping pattern;

a step for superposing both of said panel substrates upon another while sandwiching said sealing material and said liquid crystal between said both of said panel substrates; and

a step for pressing said both of said panel substrates against each other,

wherein in said sealing material coating step, a notch width of said notch portion is set to a value so that said notch portion is blocked by said first portion of said sealing material and said second portion of said sealing material merging to block said break as a result of said both of said panel substrates being pressed against each other in said substrate pressing step.

2. The method of manufacturing a liquid crystal display panel according to claim 1, wherein in said sealing material coating step, said notch width of said notch portion is set so that said notch portion is blocked before said liquid crystal reaches said notch portion after starting to press said both of said panel substrates in said substrate pressing step.

4. The method of manufacturing a liquid crystal display panel according to claim 2, wherein in said sealing material coating step, a plurality of said notch portions are provided, and of two notch portions selected arbitrarily from said plurality of said notch portions, a notch width of one notch portion which the liquid crystal reaches earlier than another notch portion in said substrate pressing step is set to be smaller than that of said other notch portion which said liquid crystal reaches later.

6. The method of manufacturing a liquid crystal display panel according to claim 1, wherein a quantity of said liquid crystal dropped in said liquid crystal dropping step is set to be equal to a volume of a layer-shaped space or less, which is formed by said both of said panel substrates and said sealing material immediately after said both of said panel substrates are superposed in said substrate pressing step.

7. The method of manufacturing a liquid crystal display panel according to claim 6, wherein said quantity of said liquid crystal dropped in said liquid crystal dropping step is set to be approximately equal to said volume of said layer-shaped space formed by said both of said panel substrates and said sealing material after said both of said panel substrates are pressed against each other in said substrate pressing step.

8. The method of manufacturing a liquid crystal display panel according to claim 6, wherein in said substrate pressing step, by pressing said both of said panel substrates against each other, said both of said panel substrates are compressively attached to each other, said liquid crystal is allowed to fill said layer-shaped space, residual gas is exhausted from said layer-shaped space through said notch portion, and said notch portion provided in said sealing material coating step is blocked.

9. The method of manufacturing a liquid crystal display panel according to claim 1, wherein in said liquid crystal dropping step, said predetermined dropping pattern is adopted based on at least dimensions of said display area used for displaying, which is said plane of said panel substrate where said electrode is formed.

10. The method of manufacturing a liquid crystal display panel according to claim 1, wherein in said sealing material coating step, said predetermined coating pattern is adopted based on at least said dimensions of said display area used for displaying, which is said plane of said panel substrate where said electrode is formed.

11. The method of manufacturing a liquid crystal display panel according to claim 9, wherein in said sealing material coating step, said sealing material is coated so as to show approximately an angular ring appearance with a predetermined width and a predetermined height.

12. The method of manufacturing a liquid crystal display panel according to claim 9, wherein in said sealing material coating step, said sealing material is coated so that said notch portion is formed at least in a corner of said display area, and in said liquid crystal dropping step, said liquid crystal is dropped on a central portion of said display area.

13. The method of manufacturing a liquid crystal display panel according to claim 11, wherein the dropping pattern of said liquid crystal is set based on an aspect ratio of said display area.

3. A method of manufacturing a liquid crystal display panel in which liquid crystal is held between a pair of panel substrates facing each other, on which an electrode is formed, comprising:

a step for coating a sealing material on a plane of a least one of said panel substrates, on which the electrode is formed, with a predetermined coating pattern having a notch portion;

a step for dropping the liquid crystal on said plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined dropping pattern;

a step for superposing both of said panel substrates upon another while sandwiching said sealing material and said liquid crystal between said both of said panel substrates; and

a step for pressing said both of said panel substrates against each other,

wherein in said sealing material coating step, a notch width of said notch portion is set to a value so that said notch portion is blocked after said both of said panel substrates are pressed against each other in said substrate pressing step,

wherein in said sealing material coating step, said notch width of said notch portion is set to be equal to an increased amount of a width of said sealing material or less, which is obtained by subtracting a width of said sealing material when said sealing material is coated in the sealing material coating step from a width of said sealing material after said both of said panel substrates are pressed against each other in said substrate pressing step.

5. A method of manufacturing a liquid crystal display panel in which liquid crystal is held between a pair of panel substrates facing each other, on which an electrode is formed, comprising:

a step for coating a sealing material on a plane of a least one of said panel substrates, on which the electrode is formed, with a predetermined coating pattern having a notch portion;

a step for dropping the liquid crystal on said plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined dropping pattern;

a step for superposing both of said panel substrates upon another while sandwiching said sealing material and said liquid crystal between said both of said panel substrates; and

a step for pressing said both of said panel substrates against each other,

wherein in said sealing material coating step, a notch width of said notch portion is set to a value so that said notch portion is blocked after said both of said panel substrates are pressed against each other in said substrate pressing step,

wherein in said sealing material coating step, said notch width of said notch portion is set to be equal to an increased amount of a width of said sealing material or less, which is obtained by subtracting a width of said sealing material when said sealing material is coated in the sealing material coating step from a width of said sealing material after said both of said panel substrates are pressed against each other in said substrate pressing step, and

wherein in said sealing material coating step, said notch width of said notch portion is set to approximately 0.75 times said increased amount of the width of said sealing material.

14. A method of manufacturing a liquid crystal display panel in which liquid crystal is held between a pair of panel substrates facing each other, on which an electrode is formed, comprising:

a step for coating a sealing material on a plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined coating pattern having a notch portion;

a step for dropping said liquid crystal on said plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined dropping pattern;

a step for superposing both of said panel substrates upon another while sandwiching said sealing material and said liquid crystal between said both of said panel substrates; and

a step for pressing said both of said panel substrates against each other,

wherein in said sealing material coating step, said sealing material surrounding a display area and a small non-display area is coated outside said display area used for displaying, which is said plane of said panel substrate where said electrode is formed, so that said small non-display area which continues to said display area is formed and a notch portion is formed on an outer periphery of said small non-display area, said notch portion comprising a break between a first portion of said outer periphery and a second portion of said outer periphery, and in said substrate pressing step, an air bubble accommodation portion for accommodating residual gas is formed in said small non-display area after said panel substrates are superposed upon another.

15. The method of manufacturing a liquid crystal display panel according to claim 14, wherein a notch width of said notch portion is set so that said notch portion is blocked after said both of said panel substrates are pressed against each other in said substrate pressing step.

16. The method of manufacturing a liquid crystal display panel according to claim 15, wherein said notch width of said notch portion is set so that said notch portion is blocked before said liquid crystal reaches said notch portion after starting to press said both of said panel substrates in said substrate pressing step.

18. The method of manufacturing a liquid crystal display panel according to claim 14, wherein in said substrate pressing step, by pressing said both of said panel substrates against each other, said both of said panel substrates are compressively attached to each other, said liquid crystal is allowed to fill a layer-shaped space corresponding to said display area, said layer-shaped space being formed by said both of said panel substrates and said sealing material, residual gas is exhausted from said layer-shaped space through said notch portion, and said notch portion provided in said sealing material coating step is blocked in a state where said residual gas is partially accommodated in said air bubble accommodation space.

17. A method of manufacturing a liquid crystal display panel in which liquid crystal is held between a pair of panel substrates facing each other, on which an electrode is formed, comprising:

a step for coating a sealing material on a plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined coating pattern having a notch portion;

a step for dropping said liquid crystal on said plane of at least one of said panel substrates, on which said electrode is formed, with a predetermined dropping pattern;

a step for superposing both of said panel substrates upon another while sandwiching said sealing material and said liquid crystal between said both of said panel substrates; and

a step for pressing said both of said panel substrates against each other,

wherein in said sealing material coating step, said sealing material surrounding a display area and a small non-display area is coated outside said display area used for displaying, which is said plane of said panel substrate where said electrode is formed, so that said small non-display area which continues to said display area is formed and a notch portion is formed on an outer periphery of said small non-display area, and in said substrate pressing step, an air bubble accommodation portion for accommodating residual gas is formed in said small non-display area after said panel substrates are superposed upon another,

wherein said notch width of said notch portion provided in said sealing material coating step is set to be equal to an increased amount of a width of said sealing material or less, which is obtained by subtracting a width of said sealing material when said sealing material is coated in said sealing material coating step from a width of said sealing material after said both of said panel substrates are pressed against each other in said substrate pressing step, and a notch width of said notch portion provided on a peripheral side of said small non-display area is set to a value smaller than a width of an opening between said display area and said small non-display area.