Liquid crystal solution, liquid crystal display device including liquid crystal solution and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-10895772-B2
Application number	US-201715582135-A
Country	US
Kind code	B2
Filing date	Apr 28, 2017
Priority date	Apr 28, 2016
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

A liquid crystal display device includes: a substrate; a thin film transistor in a pixel region over the substrate; a common electrode over the thin film transistor; a pixel electrode connected to the thin film transistor; and a liquid crystal layer including a plurality of liquid crystal capsules over the common electrode and the pixel electrode, wherein each of the plurality of liquid crystal capsules includes a shell and a core having a plurality of liquid crystal molecules therein, and wherein a gap distance between the liquid crystal molecules in adjacent liquid crystal capsules is equal to or greater than 20 nm and equal to or smaller than 0.3 times of a capsule diameter of the adjacent liquid crystal capsules.

First claim

What is claimed is:

1. A liquid crystal solution, comprising:
a plurality of liquid crystal capsules including at least one pair of liquid crystal capsules in direct contact with each other,
wherein each of the plurality of liquid crystal capsules includes a shell and a core having a plurality of liquid crystal molecules therein,
wherein a gap distance between the liquid crystal molecules in adjacent liquid crystal capsules is equal to or greater than 20 nm and equal to or smaller than 0.3 times of a capsule diameter of the adjacent liquid crystal capsules,
wherein a shell thickness of each liquid crystal capsule among the at least one pair of liquid crystal capsules is equal to or greater than 10 nm and equal to or smaller than 0.15 times of a capsule diameter of each liquid crystal capsule among the at least one pair of liquid crystal capsules,
wherein a maximum length of the at least one pair of liquid crystal capsules is greater than or equal to 90 nm and equal to or smaller than 240 nm,
wherein a refractive index of each of the plurality of liquid crystal molecules is within a range of 0.18 to 0.30, and a dielectric anisotropy of each of the plurality of liquid crystal molecules is within a range of 35 to 100,
wherein the plurality of liquid crystal capsules include at least two overlapping layers of liquid crystal capsules dispersed within the liquid crystal solution, and
wherein the liquid crystal solution has a peak transmittance that flattens between 20 volts and 30 volts, and decreases by at least 1% or more from 30 volts to 50 volts.

2. The liquid crystal solution of claim 1 , wherein the capsule diameter is within a range of 50 nm to 200 nm.

3. The liquid crystal solution of claim 2 , wherein a shell thickness of the shell is equal to or greater than 10 nm and equal to or smaller than 0.15 times of the capsule diameter.

4. The liquid crystal solution of claim 1 , wherein a volume ratio of the plurality of liquid crystal molecules with respect to the liquid crystal solution is within a range of 20% to 50%.

5. The liquid crystal solution of claim 1 , further comprising a binder, wherein the plurality of liquid crystal capsules are dispersed in the binder,
wherein the binder surrounding the plurality of liquid crystal capsules includes one of a water soluble material, a fat soluble material and a mixed material of the water soluble material and the fat soluble material, and the binder has one of a transparency and a translucence.

6. The liquid crystal solution of claim 5 , wherein the material of the binder is different from a material of the liquid crystal capsule.

7. The liquid crystal solution of claim 5 , wherein the material of the binder is the same as the material of the liquid crystal capsule.

8. The liquid crystal solution of claim 1 , further comprising a binder, wherein the plurality of liquid crystal capsules are dispersed in the binder,
wherein the binder surrounding the plurality of liquid crystal capsules includes a fat soluble material.

9. The liquid crystal solution of claim 8 , wherein the gap distance between the liquid crystal molecules in the adjacent liquid crystal capsules is determined by one of a volume ratio of the binder and the plurality of liquid crystal molecules and a volume ratio of a monomer and the plurality of liquid crystal molecules.

10. The liquid crystal solution of claim 1 , wherein a volume ratio of the plurality of liquid crystal molecules with respect to the liquid crystal solution is approximately 37% and the plurality of liquid crystal capsules are formed of poly vinyl alcohol.

11. A liquid crystal solution, comprising:
a plurality of liquid crystal capsules including at least one pair of liquid crystal capsules in direct contact with each other,
wherein each of the plurality of liquid crystal capsules includes a shell and a core having a plurality of liquid crystal molecules therein,
wherein a gap distance between the liquid crystal molecules in the at least one pair of liquid crystal capsules is equal to or greater than 20 nm and equal to or smaller than 0.3 times of a capsule diameter of each liquid crystal capsule among the at least one pair of liquid crystal capsules,
wherein a shell thickness of each liquid crystal capsule among the at least one pair of liquid crystal capsules is equal to or greater than 10 nm and equal to or smaller than 0.15 times of the capsule diameter of each liquid crystal capsule among the at least one pair of liquid crystal capsules,
wherein a maximum length of the at least one pair of liquid crystal capsules is greater than or equal to 90 nm and equal to or smaller than 240 nm,
wherein a shell of the plurality of liquid crystal capsules has a thickness within a range equal to or greater than 10 nm and equal to or smaller than 15 nm when a capsule diameter of the shell is 100 nm, the shell of the plurality of liquid crystal capsules has a thickness within a range equal to or greater than 10 nm and equal to or smaller than 20 nm when the capsule diameter of the shell is 150 nm, and the shell of the plurality of liquid crystal capsules has a thickness within a range equal to or greater than 10 nm and equal to or smaller than 30 nm when the capsule diameter of the shell is 200 nm, and
wherein the liquid crystal solution has a peak transmittance that flattens between 20 volts and 30 volts, and decreases by at least 1% or more from 30 volts to 50 volts.

Assignees

• Lg Display Co Ltd

Inventors

• Kim Kyeong-Jin
• Ha Kyung-Su
• Lee Eun-Woo

Classifications

• G02F1/1334 Primary

  based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals · CPC title

• C09D129/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• G02F1/1362

  Active matrix addressed cells {(G02F1/134336, G02F1/134363 take precedence)} · CPC title

• C09D133/12

  Homopolymers or copolymers of methyl methacrylate · CPC title

• C09K19/00

  Liquid crystal materials · CPC title