MANUFACTURING METHOD OF LIQUID CRYSTAL DISPLAY PANEL AND LIQUID CRYSTAL MEDIUM COMPOSITION

• US 20190310523A1
• Filed: 05/07/2018
• Published: 10/10/2019
• Est. Priority Date: 04/09/2018
• Status: Abandoned Application

• Current Assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: LAN, Song
• Application Number:
  US15/776,088
• Publication Number:
  US 20190310523A1
• Time in Patent Office: Days
• CPC Class Codes: C08F 2/48 by ultraviolet or visible light
• CPC Class Codes: C08F 216/36 by a ketonic radical
• CPC Class Codes: C08F 220/301 and one oxygen in the alcohol moiety
• CPC Class Codes: C08L 2203/16 used for films
• CPC Class Codes: C08L 2203/20 use in electrical or conductive gadgets
• CPC Class Codes: C08L 33/08 Homopolymers or copolymers of acrylic acid esters
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation

Abstract

A manufacturing method of a liquid crystal display panel and a liquid crystal medium composition are provided. A photoinitiator and flexible branched chains-containing active monomers are added into the liquid crystal material, and a special process condition is used. Thus, a traditional alignment film process can be omitted, and liquid crystal alignment is accomplished. Furthermore, impurity ions are prevented from diffusing into a liquid crystal layer, and quality of the liquid crystal display panel is greatly enhanced.

Claims

1. A manufacturing method of a liquid crystal display panel, comprising steps of:

providing an upper substrate, a lower substrate, and a liquid crystal medium composition, wherein the liquid crystal medium composition comprises a liquid crystal material, a photoinitiator, and flexible branched chains-containing active monomers, wherein the liquid crystal material comprises liquid crystal molecules;

dripping the liquid crystal medium composition onto one of the upper substrate and the lower substrate, coating a sealant on a region of the upper substrate and the lower substrate corresponding to a periphery of the liquid crystal medium composition, assembling and attaching the upper substrate with the lower substrate, and curing the sealant, wherein a liquid crystal layer is formed by the liquid crystal medium composition which is disposed between the upper substrate and the lower substrate;

heating the liquid crystal layer, and after a conformation of the liquid crystal molecule changes, applying a first ultraviolet irradiation to the liquid crystal layer while heating, such that a portion of the active monomers react with the photoinitiator and the active monomers are deposited on both the upper substrate and the lower substrate, thus aligning the liquid crystal molecules perpendicular to the upper substrate and the lower substrate; and

applying a voltage to two sides of the liquid crystal layer, and after the liquid crystal molecules are deflected, applying a second ultraviolet irradiation to the liquid crystal layer while applying the voltage, such that another portion of the active monomers react with the photoinitiator, causing continued deposition of the active monomers on both the upper substrate and the lower substrate, thus having the liquid crystal molecules generate a pretilt angle;

wherein after the step of applying voltage to the two sides of the liquid crystal layer, and after the liquid crystal molecules are deflected, applying the second ultraviolet irradiation to the liquid crystal layer while applying the voltage, such that the another portion of the active monomers react with the photoinitiator, causing continued deposition of the active monomers on both the upper substrate and the lower substrate, thus having the liquid crystal molecules generate the pretilt angle, the method further comprises;

removing the voltage which is applied to the two sides of the liquid crystal layer, and then applying a third ultraviolet irradiation to the liquid crystal layer, such that the active monomers completely react with the photoinitiator; and

wherein in relation to the liquid crystal medium composition, a mass percentage of the liquid crystal material is 94.5%-98.9%, a mass percentage of the active monomers is 1%-5%, and a mass percentage of the photoinitiator is 0.1%-0.5%.

2. The manufacturing method of the liquid crystal display panel according to claim 1, wherein a duration for applying the first ultraviolet light irradiation to the liquid crystal layer is between 1 minute to 60 minutes, and a duration for applying the second ultraviolet light irradiation to the liquid crystal layer is between 30 seconds to 200 seconds, and a duration for applying the third ultraviolet light irradiation to the liquid crystal layer is between 30 minutes to 100 minutes.

3. The manufacturing method of the liquid crystal display panel according to claim 1, wherein the first ultraviolet irradiation, the second ultraviolet light irradiation, and the third ultraviolet light irradiation cause the active monomers to react with the photoinitiator, and a first polymer layer and a second polymer layer are formed on the upper substrate and the lower substrate, respectively, wherein a thickness of each of the first polymer layer and the second polymer layer is between 200 angstroms to 1200 angstroms.

4. The manufacturing method of the liquid crystal display panel according to claim 1, wherein the active monomers are at least one of:

5. The manufacturing method of the liquid crystal display panel according to claim 1, wherein the photoinitiator is one of azobisisobutyronitrile, dialkyl peroxides, diacyl peroxides, peroxy esters, and any combination thereof.

6. The manufacturing method of the liquid crystal display panel according to claim 1, wherein the liquid crystal layer is heated to a temperature of 70°

C. to 100°

C.

7. The manufacturing method of the liquid crystal display panel according to claim 1, wherein an intensity of each of the first ultraviolet light irradiation, the second ultraviolet light irradiation and the third ultraviolet light irradiation is between 85 mW/cm² to 100 mW/cm².

8. A manufacturing method of the liquid crystal display panel, comprises steps of:

providing an upper substrate, a lower substrate, and a liquid crystal medium composition, wherein the liquid crystal medium composition comprises a liquid crystal material, a photoinitiator, and flexible branched chains-containing active monomers, wherein the liquid crystal material comprises liquid crystal molecules;

dripping the liquid crystal medium composition onto one of the upper substrate and the lower substrate, coating a sealant on a region of the upper substrate and the lower substrate corresponding to a periphery of the liquid crystal medium composition, assembling and attaching the upper substrate with the lower substrate, and curing the sealant, wherein a liquid crystal layer is formed by the liquid crystal medium composition which is disposed between the upper substrate and the lower substrate;

heating the liquid crystal layer, and after a conformation of the liquid crystal molecule changes, applying a first ultraviolet irradiation to the liquid crystal layer while heating, such that a portion of the active monomers react with the photoinitiator and the active monomers are deposited on both the upper substrate and the lower substrate, and thus aligning the liquid crystal molecules perpendicular to the upper substrate and the lower substrate; and

applying a voltage to two sides of the liquid crystal layer, and after the liquid crystal molecules are deflected, applying a second ultraviolet irradiation to the liquid crystal layer while applying the voltage, such that another portion of the active monomers react with the photoinitiator, causing continued deposition of the active monomers on both the upper substrate and the lower substrate, and the liquid crystal molecules generate a pretilt angle.

9. The manufacturing method of the liquid crystal display panel according to claim 8, wherein after the step of applying voltage to the two sides of the liquid crystal layer, and after the liquid crystal molecules are deflected, applying the second ultraviolet irradiation to the liquid crystal layer while applying the voltage, such that the another portion of the active monomers react with the photoinitiator, causing continued deposition of the active monomers on both the upper substrate and the lower substrate, thus having the liquid crystal molecules generate the pretilt angle, the method further comprises:

removing the voltage which is applied to the two sides of the liquid crystal layer, and then applying a third ultraviolet irradiation to the liquid crystal layer, such that the active monomers completely react with the photoinitiator.

10. The manufacturing method of the liquid crystal display panel according to claim 9, wherein a duration for applying the first ultraviolet light irradiation to the liquid crystal layer is between 1 minute to 60 minutes, and a duration for applying the second ultraviolet light irradiation to the liquid crystal layer is between 30 seconds to 200 seconds, and a duration for applying the third ultraviolet light irradiation to the liquid crystal layer is between 30 minutes to 100 minutes.

11. The manufacturing method of the liquid crystal display panel according to claim 9, wherein the first ultraviolet irradiation, the second ultraviolet light irradiation, and the third ultraviolet light irradiation cause the active monomers to react with the photoinitiator, and a first polymer layer and a second polymer layer are formed on the upper substrate and the lower substrate, respectively, wherein a thickness of each of the first polymer layer and the second polymer layer is between 200 angstroms to 1200 angstroms.

12. The manufacturing method of the liquid crystal display panel according to claim 8, wherein in relation to the liquid crystal medium composition, a mass percentage of the liquid crystal material is 94.5%-98.9%, a mass percentage of the active monomers is 1%-5%, and a mass percentage of the photoinitiator is 0.1%-0.5%.

13. The manufacturing method of the liquid crystal display panel according to claim 8, wherein the active monomers are at least one of:

14. The manufacturing method of the liquid crystal display panel according to claim 8, wherein the photoinitiator is one of azobisisobutyronitrile, dialkyl peroxides, diacyl peroxides, peroxy esters, and any combination thereof.

15. The manufacturing method of the liquid crystal display panel according to claim 8, wherein the liquid crystal layer is heated to a temperature of 70°

C. to 100°

C.

16. The manufacturing method of the liquid crystal display panel according to claim 9, wherein an intensity of each of the first ultraviolet light irradiation, the second ultraviolet light irradiation and the third ultraviolet light irradiation is between 85 mW/cm² to 100 mW/cm².

17. A liquid crystal medium composition, comprising:

a liquid crystal material, a photoinitiator, and flexible branched chains-containing active monomers, wherein the liquid crystal material comprises liquid crystal molecules;

wherein the active monomers are at least one of;