Electrowetting elements

1. An electrowetting element comprising a first support plate, a second support plate and an electrode,

wherein a space between the support plates contains a first fluid and a second fluid, wherein:

the first fluid is immiscible with the second fluid;

the second fluid is at least one of electrically conductive or polar; and

the first fluid comprises a non-polar carrier fluid in which is dissolved a dye having a general formula selected from the group consisting of:

wherein Q has the general formula: -Het1R1 or -Het1R1R2;

V has the general formula: -Het2R3 or -Het2R3R4;

Het1 and Het2 are heteroatoms;

R1 and R3 are H;

R2 and R4 are both at least one of H, an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms or a cyclic alkyl group comprising 1 to 20 carbon atoms, and at least one of R2 and R4 comprises at least one of a branched alkyl group comprising 4 to 16 carbon atoms or a cyclic alkyl group comprising 4 to 16 carbon atoms; T and U are at least one of H, an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms, a cyclic alkyl group comprising 1 to 20 carbon atoms, or a functional group including a heteroatom, wherein where T is said functional group including a heteroatom, T has the general formula: -Het3, -Het3R5or -Het3R5R6, and where U is said functional group including a heteroatom, U has the general formula: -Het4, -Het4R7 or -Het4R7R8, wherein Het3 and Het4 are heteroatoms and R5, R6, R7 and R8 are at least one of H, an alkyl group comprising 1 to 20 carbon atoms a branched alkyl group comprising 1 to 20 carbon atoms or a cyclic alkyl group comprising 1 to 20 carbon atoms;

W, X, Y and Z are H or an alkyl group; and

F, G, L and M are H or an alkyl group.

2. An electrowetting element according to claim 1 , wherein at least one of T and U is at least one of an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms or a cyclic alkyl group comprising 1 to 20 carbon atoms.

3. An electrowetting element according to claim 1 , wherein T and U are H.

4. An electrowetting element according to claim 1 , wherein any one of R2, R4, T and U includes a cyclic alkyl group selected from the group consisting of: cyclo-pentane, cyclo-hexane or cyclo-heptane.

5. An electrowetting element according to claim 1 , wherein R2 and R4 are both at least one of branched alkyl groups comprising 4 to 16 carbon atoms or cyclic alkyl groups comprising 4 to 16 carbon atoms.

6. An electrowetting element according to claim 1 , wherein the H of each of R1 and R3 is arranged to form a bridging interaction with a C═O group of said dye.

7. An electrowetting element according to claim 6 , wherein at least one of Q and V has a formula selected from the group consisting of: —OH, —NHR2 or —NHR4.

8. An electrowetting element according to claim 1 , said dye having the general formula:

wherein at least one of W, X, Y and Z is at least one of H, an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms or a cyclic alkyl group comprising 1 to 20 carbon atoms.

9. An electrowetting element according to claim 8 , wherein any one of W, X, Y and Z includes a cyclic alkyl group selected from the group consisting of: cyclo-pentane, cyclo-hexane or cyclo-heptane.

10. An electrowetting element according to claim 8 , wherein W, X, Y and Z are H.

11. An electrowetting element according to claim 10 , said dye having a formula selected from the group consisting of:

12. An electrowetting element according to claim 8 , wherein R2 and R4 are cyclo-hexane.

13. An electrowetting element according to claim 10 , said dye having a formula selected from the group consisting of:

14. An electrowetting element according to claim 1 , said dye having the general formula:

wherein at least one of F, G, L and M is at least one of H, an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms or a cyclic alkyl group comprising 1 to 20 carbon atoms.

15. An electrowetting element according to claim 14 , wherein L and M are H.

16. An electrowetting element according to claim 15 , said dye having the general formula:

wherein F and G are H.

17. An electrowetting element according to claim 1 , wherein at least one of T and U is a functional group including a heteroatom, T having the general formula: -Het3, -Het3R5or -Het3R5R6, and U having the general formula: -Het4, -Het4R7 or -Het4R7R8, wherein Het3 and Het4 are heteroatoms and R5, R6, R7 and R8 are at least one of H, an alkyl group comprising 1 to 20 carbon atoms, on a branched alkyl group comprising 1 to 20 carbon atoms or on a cyclic alkyl group comprising 1 to 20 carbon atoms.

18. An electrowetting element according to claim 1 , wherein the carrier fluid comprises an alkane.

19. An electrowetting element according to claim 1 comprising at least one further dye dissolved in the carrier fluid.

20. An optical display device comprising at least one electrowetting element of claim 1 .

21. An electrowetting element according to claim 10 , wherein T is H, U is one of an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms, or a cyclic alkyl group comprising 1 to 20 carbon atoms, Q has the formula —NHR2 wherein R2 is one of: a branched alkyl group comprising 4 to 16 carbon atoms, or a cyclic alkyl group comprising 4 to 16-carbon atoms, and V is OH.

22. An electrowetting element according to claim 21 , wherein the alkyl group of U is one of: a branched alkyl group, or a cyclic alkyl group.

23. An electrowetting element according to claim 10 , wherein T has the formula -Het3R5 wherein Het3 is S and R5 is one of an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms, or a cyclic alkyl group comprising 1 to 20 carbon atoms, U is H, Q has the formula —NHR2, wherein R2 is one of an alkyl group comprising 1 to 20 carbon atoms, a branched alkyl group comprising 1 to 20 carbon atoms, or a cyclic alkyl group comprising 1 to 20 carbon atoms, and V has the formula —NHR4 wherein R4 is one of: a branched alkyl group comprising 4 to 16 carbon atoms, or a cyclic alkyl group comprising 4 to 16 carbon atoms.

24. An electrowetting element according to claim 23 , wherein at least one of the alkyl group of R5 and the alkyl group of R2 is one of: a branched alkyl group, or a cyclic alkyl group.