Liquid crystal composition, liquid crystal display and method of manufacturing liquid crystal display

• US 6,633,348 B2
• Filed: 09/25/2001
• Issued: 10/14/2003
• Est. Priority Date: 09/26/2000
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Naito, Katsuyuki, Yamamoto, Takeshi, Shohara, Kiyoshi, Fukuoka, Nobuko, Maya, Natsuko
• Primary Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US09/961,337
• Publication Number:
  US 20020061367A1
• Time in Patent Office: 749 Days
• Field of Search: 349/1, 349/182, 252/299.01, 252/299.5, 428/1.1
• US Class Current: 349/1
• CPC Class Codes: C09K 19/02 characterised by optical, electrical or physical properties of the components, in general
• CPC Class Codes: C09K 19/3001 Cyclohexane rings
• CPC Class Codes: C09K 19/3068 chain containing -COO- or -OCO- groups
• CPC Class Codes: C09K 2019/301 Cy-Cy-Ph
• CPC Class Codes: C09K 2019/3012 Cy-Cy-Cy-Ph, or more Cy rings
• CPC Class Codes: C09K 2019/3016 Cy-Ph-Ph
• CPC Class Codes: C09K 2019/3019 Cy-Cy-Ph-Ph
• CPC Class Codes: C09K 2019/3077 Cy-Cy-COO-Ph
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition

Abstract

There is provided a liquid crystal display including a first substrate, a second substrate facing the first substrate, and a liquid crystal layer intervening between the first and second substrates and containing liquid crystal substances different from each other, a sum of values each calculated from a formula: X_α(RTlogP_α+HE_α) for all the liquid crystal substances in the liquid crystal layer being 32 kJ/mol or higher, wherein X_α denotes a molar fraction of a component α in the liquid crystal layer, P_α denotes a distribution ratio of the component α between an aqueous phase and a 1-octanol phase, HE_α denotes a hydration energy for 1 mol of the component α, R denotes a gas constant of 8.3 J/K·mol, and T denotes a temperature of 300 K.

Claims

1. A liquid crystal display comprising:

a first substrate;

a second substrate facing the first substrate; and

a liquid crystal layer intervening between the first and second substrates and containing liquid crystal substances different from each other, a sum of values each calculated from a formula;

2. The display according to claim 1, wherein the first substrate comprises a color filter layer facing the second substrate, and pixel electrodes between the color filter layer and the liquid crystal layer.

3. The display according to claim 1,

wherein the first substrate comprises pixel electrodes facing the second substrate, switching elements electrically connected to the pixel electrodes, signal lines electrically connected to the switching elements, and scanning lines crossing the signal lines,

wherein the second substrate comprises a common electrode facing the first substrate, and

wherein either one of the first and second substrates further comprises a color filter layer facing another of the first and second substrates.

4. The display according to claim 1, wherein the sum is 33.2 kJ/mol or higher.

5. The display according to claim 1, wherein the sum is 45.7 kJ/mol or higher.

6. The display according to claim 1, wherein at least one of the liquid crystal substances comprises an alkyl group which includes at least two carbon atoms, and wherein the distribution ratio Pα

and the hydration energy HEα

of the liquid crystal substance which comprises the alkyl group are obtained supposing that the alkyl group is an n-pentyl group.

7. A method of manufacturing a liquid crystal display, the display comprising a pair of substrates and a liquid crystal layer intervening between the substrates and containing liquid crystal substances different from each other, comprising:

determining a composition of the liquid crystal layer based on a sum of values each calculated from a formula;

8. The method according to claim 7, wherein the determination of the composition is carried out to make the sum be 32.2 kJ/mol or higher under a condition where the distribution ratio Pα

is a distribution ratio of the component α

between an aqueous phase and a 1-octanol phase, the gas constant R is 8.3 J/K·

mol, and the temperature T is 300 K.

9. The method according to claim 7, wherein the determination of the composition is carried out to make the sum be 45.7 kJ/mol or higher under a condition where the distribution ratio Pα

is a distribution ratio of the component α

between an aqueous phase and a 1-octanol phase, the gas constant R is 8.3 J/K·

mol, and the temperature T is 300 K.

10. The method according to claim 7, wherein at least one of the liquid crystal substances comprises an alkyl group which includes at least two carbon atoms, and wherein the distribution ratio Pα

and the hydration energy HEα

of the liquid crystal substance which comprises the alkyl group are obtained supposing that the alkyl group is an n-pentyl group.

11. A liquid crystal composition comprising liquid crystal substances different from each other, a sum of values each calculated from a formula:

12. The composition according to claim 11, wherein the sum is 33.2 kJ/mol or higher.

13. The composition according to claim 11, wherein the sum is 45.7 kJ/mol or higher.

14. The composition according to claim 11, wherein at least one of the liquid crystal substances comprises an alkyl group which includes at least two carbon atoms, and wherein the distribution ratio Pα

and the hydration energy HEα

of the liquid crystal substance which comprises the alkyl group are obtained supposing that the alkyl group is an n-pentyl group.