Electro-optic device

• US 4,231,641 A
• Filed: 09/27/1978
• Issued: 11/04/1980
• Est. Priority Date: 11/29/1975
• Status: Expired due to Term

• Current Assignee: ETS Incorporated (AKKA Technologies SE)
• Original Assignee: Ebauches SA
• Inventors: Randin, Jean-Paul
• Primary Examiner(s): Edmundson, F. C.
• Application Number:
  US05/946,147
• Time in Patent Office: 769 Days
• Field of Search: 204/242, 350/350, 350/357
• US Class Current: 359/274
• CPC Class Codes: G02F 1/1525 characterised by a particular ion transporting layer, e.g. electrolyte

Abstract

An electro-optic device comprising a transparent conductive layer, an electrochromic layer applied on the said transparent layer, these two first elements constituting together a first electrode, a counter-electrode maintained at distance from the said first electrode, and an electrolyte ensuring an ionic binding between the electrode and the counter-electrode. Preferably, the electrolyte is a polymer of linear molecules such as polystyrene sulfonic acid including a pigment.

A combination cell of a perfluorosulfonic acid polymer membrane and polystyrene sulfonic acid is disclosed.

Claims

1. Electro-optic device comprising a transparent conductive layer, an electrochromic layer applied on the said transparent layer, these two first elements constituting together a first electrode, a counter-electrode maintained at distance from the said first electrode, and an electrolyte ensuring an ionic binding between the electrode and the counter-electrode, characterized by the fact that the said electrolyte is made of solid or pasty organic material constituted by at least a polymer comprising ionic groups of the type used as ion-exchange materials, the said material of the electrolyte being chemically stable and compatible with that of the electrochromic layer.

2. Electro-optic device as claimed in claim 1, characterized by the fact that the molecular weight of the electrolyte is higher than 1000.

3. Electro-optic device as claimed in claim 1, characterized by the fact that the electrolyte is constituted by linear molecules.

4. Electro-optic device as claimed in claim 1, characterized by the fact that the electrolyte is constituted by cross-linked molecules.

5. Electro-optic device as claimed in claim 1, characterized by the fact that the electrolyte is homogeneous.

6. Electro-optic device as claimed in claim 1, characterized by the fact that the electrolyte is heterogeneous.

7. Electro-optic device as claimed in claim 1, characterized by the fact that the polymer constituting the electrolyte is in acid form.

8. Electro-optic device as claimed in claim 1, characterized by the fact that the polymer constituting the electrolyte is in salt form.

9. Electro-optic device as claimed in claim 7, characterized by the fact that the polymer is polystyrene sulfonic acid.

10. Electro-optic device as claimed in claim 7, characterized by the fact that the polymer is polyacrylic acid.

11. Electro-optic device as claimed in claim 7, characterized by the fact that the polymer is polymethacrylic acid.

12. Electro-optic device as claimed in claim 7, characterized by the fact that the polymer is phenol sulfonic acid.

13. Electro-optic device as claimed in claim 1, characterized by the fact that the polymer constituting the electrolyte in a base form.

14. Electro-optic device as claimed in claim 13, characterized by the fact that the polymer is a quaternary ammonium salt.

15. Electro-optic device as claimed in claim 1, characterized by the fact that the polymer contains a liquid having a high dielectric constant.

16. Electro-optic device as claimed in claim 1, characterized by the fact that the polymer contains a pigment.

17. Electro-optic device as claimed in claim 16, characterized by the fact that it is constituted by a cell having only one compartment filled with the electrolyte containing several pigments of different colors in different areas so as to produce a multicolored display.

18. Electro-optic device as claimed in claim 1, characterized by the fact that its electrode is constituted by an electrochromic material suitable for forming a bronze of a transition metal.

19. Electro-optic device as claimed in claim 18, characterized by the fact that its counter-electrode is constituted by the same electro-chromic material as the electrode in the reduced state.

20. Electro-optic device as claimed in claim 1, characterized by the fact that its counter-electrode is made of finely divided carbon.

21. Electro-optic device as claimed in claim 1, characterized by the fact that it comprises a film of ion-exchange polymers deposited on the electrochromic layer.

22. Electro-optic device as claimed in claim 21, characterized by the fact that the electrolyte ensures the ionic binding between the said film and the counter-electrode.

23. Electro-optic device as claimed in claim 1, characterized by the fact that it comprises a film of ion-exchange polymers deposited on the layer constituting the auxiliary electrode or counter-electrode.

24. Electro-optic device as claimed in claim 21, in which a second film of ion-exchange polymer constituted by a perfluorosulfonic acid is employed.

25. Electro-optic device as claimed in claim 21 in which the electrolyte is a cation exchange polymer in a pasty state.

26. Electro-optic device as claimed in claim 23 in which a second film of ion-exchange polymer constituted by a perfluorosulfonic acid is used.

27. Electro-optic device as claimed in claim 23 in which the electrolyte is a cation exchange polymer in a pasty state.

29. Electro-optic device as claimed in claim 1, characterized by the fact that its counter electrode is constituted by an electro-chromic material which is different from this of the electrode.

28. Electro-optic device comprising a transparent conductive layer, an electrochromic coating applied on the said transparent layer, these two first elements constituting together a first electrode, a counter-electrode and an electrolyte ensuring an ionic binding between the electrode and the counter-electrode, characterized by the fact that the said electrolyte is made of an elastomeric organic material constituted by at least a polymer comprising ionic groups of the type used as ion-exchange materials, the said material of the electrolyte being chemically stable and compatible with that of the electrochromic layer.

30. Electro-optic device comprising a transparent conductive layer, an electrochromic coating applied on the said transparent layer, these two first elements constituting together a first electrode, a counter-electrode of a material different from the first electrode and a homogenous electrolyte ensuring an ionic binding between the electrode and the counter-electrode, characterized by the fact that the said electrolyte is made of an elastomeric organic material constituted by at least a linear acidic polymer comprising ionic groups of the type used as ion-exchange materials, the said material of the electrolyte being chemically stable and compatible with that of the electrochromic layer.