Polymeric dispersed liquid crystal light shutter device

• US 7,837,897 B2
• Filed: 04/27/2009
• Issued: 11/23/2010
• Est. Priority Date: 04/27/2009
• Status: Active Grant

• Current Assignee: Polytronix Inc.
• Original Assignee: Polytronix Inc.
• Inventors: Tsai, Menting Tim, Zhang, Guomin
• Primary Examiner(s): WU, SHEAN CHIU
• Application Number:
  US12/430,179
• Publication Number:
  US 20100271571A1
• Time in Patent Office: 575 Days
• Field of Search: 252/299.01, 252/299.63, 252/299.66, 349/56, 349/62, 349/88, 359/245, 359/254, 359/321
• US Class Current: 252/299.01
• CPC Class Codes: C09K 19/44 containing compounds with benzene rings directly linked
• CPC Class Codes: C09K 19/544 as dispersing or encapsulating medium around the liquid crystal
• CPC Class Codes: C09K 2019/123 Ph-Ph-Ph
• CPC Class Codes: C09K 2019/3009 Cy-Ph
• CPC Class Codes: C09K 2019/301 Cy-Cy-Ph
• CPC Class Codes: C09K 2019/3016 Cy-Ph-Ph
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 2203/68 Green display, e.g. recycling, reduction of harmful substances

Abstract

A polymer dispersed liquid crystal light shutter device and method for use of the same are disclosed. First and second substrates are disposed substantially parallel. A polymer binder system is interposed between the first and second substrates and a plurality of liquid crystals are dispersed in the polymer binder system. The liquid crystal shutter device is able to switch between a high light absorbing dark state and a low light absorbing transparent state, and visa versa, with a low driving voltage. The liquid crystal shutter device includes formulations of liquid crystal mixtures having nematic liquid crystals and polymer systems to provide a wide viewing angle, low driving voltage, high contrast ratio, for example.

Claims

1. A polymer dispersed liquid crystal light shutter device comprising:

first and second substrates disposed substantially parallel;

a polymer binder system interposed between the first and second substrates; and

a plurality of liquid crystals dispersed in the polymer binder system, the plurality of liquid crystals comprise a mixture product of at least one compound expressed by the general formula (I), at least one compound expressed by the general formula (II), at least one compound expressed by the general formula (III), at least one compound expressed by the general formula (IV), and at least one compound selected from the group of compounds expressed by the general formulas (V), (VI), and (VII),

2. The polymer dispersed liquid crystal light shutter device as recited in claim 1, wherein the plurality of liquid crystals further comprise a mixture product of at least two compounds expressed by the general formula (I).

3. The polymer dispersed liquid crystal light shutter device as recited in claim 1, wherein the liquid crystal light shutter device is switched between a high light absorbing dark state and a low light absorbing transparent state by the application and removal of a voltage.

4. The polymer dispersed liquid crystal light shutter device as recited in claim 1, wherein the first and second substrates each further comprise a transparent body having a transparent conducing layer therewith.

5. The polymer dispersed liquid crystal light shutter device as recited in claim 4, wherein the transparent body is selected from materials consisting of glasses and plastics.

6. The polymer dispersed liquid crystal light shutter device as recited in claim 4, wherein the transparent body comprises a refractive index from about 1.51 to about 1.52.

7. The polymer dispersed liquid crystal light shutter device as recited in claim 4, wherein the transparent conducting layer comprises an indium-tin-oxide conducting layer.

8. The polymer dispersed liquid crystal light shutter device as recited in claim 1, wherein the polymer binder system further comprises epoxy resins and mercaptan curing agents.

9. A liquid crystal composition for a polymer dispersed liquid crystal light shutter device, the liquid crystal composition comprising:

a mixture product of at least one compound expressed by the general formula (I), at least one compound expressed by the general formula (II), at least one compound expressed by the general formula (III), at least one compound expressed by the general formula (IV), and at least one compound selected from the group of compounds expressed by the general formulas (V), (VI), and (VII),

10. The polymer dispersed liquid crystal light shutter device as recited in claim 9, wherein the plurality of liquid crystals further comprise a mixture product of at least two compounds expressed by the general formula (I).

11. A polymer dispersed liquid crystal light shutter device comprising:

first and second substrates disposed substantially parallel;

a polymer binder system interposed between the first and second substrates; and

a plurality of liquid crystals dispersed in the polymer binder system, the plurality of liquid crystals comprise a mixture product of at least one compound expressed by the general formula (I), at least one compound expressed by the general formula (II), at least one compound expressed by the general formula (III), at least one compound expressed by the general formula (IV), and at least one compound expressed by the general formula (V),

12. The polymer dispersed liquid crystal light shutter device as recited in claim 11, wherein the at least one compound expressed by the general formula (I) comprises about 10% to about 50% by weight of the plurality of liquid crystals.

13. The polymer dispersed liquid crystal light shutter device as recited in claim 11, wherein the at least one compound expressed by the general formula (II) comprises about 10% to about 20% by weight of the plurality of liquid crystals.

14. The polymer dispersed liquid crystal light shutter device as recited in claim 11, wherein the at least one compound expressed by the general formula (III) comprises about 10% to about 15% by weight of the plurality of liquid crystals.

15. The polymer dispersed liquid crystal light shutter device as recited in claim 11, wherein the at least one compound expressed by the general formula (IV) comprises about 5% to about 15% by weight of the plurality of liquid crystals.

16. The polymer dispersed liquid crystal light shutter device as recited in claim 11, wherein the at least one compound expressed by the general formula (V) comprises about 5% to about 15% by weight of the plurality of liquid crystals.

17. A polymer dispersed liquid crystal light shutter device comprising:

first and second substrates disposed substantially parallel;

a polymer binder system interposed between the first and second substrates; and

a plurality of liquid crystals dispersed in the polymer binder system, the plurality of liquid crystals comprise a mixture product of at least one compound expressed by the general formula (I), at least one compound expressed by the general formula (II), at least one compound expressed by the general formula (III), at least one compound expressed by the general formula (IV), and at least one compound expressed by the general formula (VI),

18. The polymer dispersed liquid crystal light shutter device as recited in claim 17, wherein the at least one compound expressed by the general formula (I) comprises about 10% to about 50% by weight of the plurality of liquid crystals.

19. The polymer dispersed liquid crystal light shutter device as recited in claim 17, wherein the at least one compound expressed by the general formula (II) comprises about 10% to about 20% by weight of the plurality of liquid crystals.

20. The polymer dispersed liquid crystal light shutter device as recited in claim 17, wherein the at least one compound expressed by the general formula (III) comprises about 10% to about 15% by weight of the plurality of liquid crystals.

21. The polymer dispersed liquid crystal light shutter device as recited in claim 17, wherein the at least one compound expressed by the general formula (IV) comprises about 5% to about 15% by weight of the plurality of liquid crystals.

22. The polymer dispersed liquid crystal light shutter device as recited in claim 17, wherein the at least one compound expressed by the general formula (VI) comprises about 5% to about 15% by weight of the plurality of liquid crystals.

23. A polymer dispersed liquid crystal light shutter device comprising:

first and second substrates disposed substantially parallel;

a polymer binder system interposed between the first and second substrates; and

a plurality of liquid crystals dispersed in the polymer binder system, the plurality of liquid crystals comprise a mixture product of at least one compound expressed by the general formula (I), at least one compound expressed by the general formula (II), at least one compound expressed by the general formula (III), at least one compound expressed by the general formula (IV), and at least one compound expressed by the general formula (VII),

24. The polymer dispersed liquid crystal light shutter device as recited in claim 23, wherein the at least one compound expressed by the general formula (I) comprises about 10% to about 50% by weight of the plurality of liquid crystals.

25. The polymer dispersed liquid crystal light shutter device as recited in claim 23, wherein the at least one compound expressed by the general formula (II) comprises about 10% to about 20% by weight of the plurality of liquid crystals.

26. The polymer dispersed liquid crystal light shutter device as recited in claim 23, wherein the at least one compound expressed by the general formula (III) comprises about 10% to about 15% by weight of the plurality of liquid crystals.

27. The polymer dispersed liquid crystal light shutter device as recited in claim 23, wherein the at least one compound expressed by the general formula (IV) comprises about 5% to about 15% by weight of the plurality of liquid crystals.

28. The polymer dispersed liquid crystal light shutter device as recited in claim 23, wherein the at least one compound expressed by the general formula (VII) comprises about 5% to about 15% by weight of the plurality of liquid crystals.