Electrochemichromic solutions, processes for preparing and using the same, and devices manufactured with the same

• US 5,500,760 A
• Filed: 08/27/1992
• Issued: 03/19/1996
• Est. Priority Date: 09/06/1991
• Status: Expired due to Fees

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Varaprasad, Desaraju V., Zhao, Mingtang, Lynam, Niall R., Looman, Steven D., Habibi, Hamid R.
• Primary Examiner(s): Epps, Georgia Y.
• Assistant Examiner(s): Lester, Evelyn A.
• Application Number:
  US07/935,784
• Time in Patent Office: 1,300 Days
• Field of Search: 359/265, 359/275, 359/272, 359/270, 252/586
• US Class Current: 359/272
• CPC Class Codes: C09K 9/02 Organic tenebrescent materials
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G02F 2001/1502 complementary cell
• CPC Class Codes: G02F 2001/15145 the electrochromic layer comprises a mixture of anodic and cathodic compounds

Abstract

The present invention relates to electrochromic solutions and devices manufactured therefrom. More precisely, the present invention relates to electrochemichromic compounds and processes for preparing the same. The present invention also relates to electrochemichromic solutions of such compounds, and those devices manufactured with the same, that demonstrate superior responsiveness to those solutions known heretofore when an applied potential is introduced thereto. And, these solutions, when contained within electrochemichromic devices, demonstrate ultraviolet stability, thermal stability and cycle stability. The responsiveness observed in terms of solution coloring with respect to the solutions, and devices containing the same, of the present invention is of a greater rapidity, intensity and uniformity than those electrochemichromic solutions of the prior art. Preparation of these solutions involve the novel process of pre-treating at least one of the electrochemichromic compounds with a redox agent prior to placing it in contact with the other electrochemichromic compound. Moreover, the present invention relates to methods of preparing such novel solutions and processes for using these solutions to provide devices that exhibit and benefit from the aforementioned superior characteristics.

Claims

1. An electrochemichromic solution capable of color change when an applied potential is introduced thereto, said electrochemichromic solution comprising:

(a) at least one anodic compound, said anodic compound having been previously contacted with a redox agent such that said anodic compound exists in a different valence state than prior to having been contacted with said redox agent, wherein said anodic compound may be a member selected from the class of chemical compounds consisting of the following formulae;

##STR8## wherein X and Y may be the same or different and each may be selected from the group consisting of H, any halogen and NRR₁, wherein R and R₁ may be the same or different and each may be selected from the group consisting of H or any straight- or branched-chain alkyl constituent having from about one carbon atom to about three carbon atoms;

or X and Y, taken together, represent an aromatic ring structure having six carbon ring atoms when viewed in conjunction with the ring carbon atoms to which they are attached; and

Z is OH or NRR₁, or salts thereof;

and combinations thereof

(b) at least one cathodic compound; and

(c) a solvent wherein the redox potential of said at least one anodic compound in said different valence state is greater than the redox potential of said at least one cathodic compound while contacted with said solvent.

2. The electrochemichromic solution according to claim 1, wherein said at least one anodic compound is a combination of two or more anodic compounds, wherein at least one of said at least one anodic compound in said combination need not be pre-contacted with said redox agent.

3. The electrochemichromic solution according to claim 1, wherein said anodic compound further may be represented by the formula below:

##STR9## wherein A is O, S or NRR₁ ;

wherein R and R₁ may be the same or different and each may be selected from the group consisting of H or any straight- or branched-chain alkyl constituent having from about one carbon atom to about six carbon atoms, provided that when A is NRR₁, Q is H, OH or NRR₁ ;

D is O, S, NR₁ or Se;

E is R₁, COOH or CONH₂ ;

G is H;

J is H, any straight- or branched-chain alkyl constituent having from about one carbon atom to about six carbon atoms, NRR₁, ##STR10## OR₁, phenyl, 2,4-dihydroxyphenyl or any halogen;

or G and J, taken together, represent an aromatic ring structure having six carbon ring atoms when viewed in conjunction with the ring carbon atoms to which they are attached;

L is H or OH;

M is H or any halogen;

T is R₁, phenyl or 2,4-dihydroxyphenyl; and

Q is H, OH or NRR₁.

4. The electrochemichromic solution according to claim 3, wherein N in said anodic compound is an N-oxide.

5. The electrochemichromic solution according to claim 3, wherein when A of said anodic compound is NRR₁, a salt selected from the group consisting of tetrafluoroborate, perchlorate, trifluoromethane sulfonate, hexafluorophosphate, acetate and any halogen is associated therewith.

6. The electrochemichromic solution according to claim 3, wherein when Q of said anodic compound is OH, a salt selected from the group consisting of any alkali metal is associated therewith.

7. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR11##

8. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR12##

9. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR13##

10. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR14##

11. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR15##

12. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR16##

13. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR17##

14. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR18##

15. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR19##

16. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR20##

17. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR21##

18. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR22##

19. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR23##

20. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR24##

21. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR25##

22. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR26##

23. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR27##

24. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR28##

25. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR29##

26. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR30##

27. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR31##

28. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR32##

29. The electrochemichromic solution according to claim 3, wherein said anodic compound is represented by the formula below:

##STR33##

30. The electrochemichromic solution according to claim 1, wherein said at least one anodic compound has been isolated after having been contacted with said redox agent.

31. The electrochemichromic solution according to claim 30, wherein said isolated at least one anodic compound further may be represented by the formula below:

##STR34##

32. The electrochemichromic solution according to claim 1, wherein said anodic compound is ##STR35##

33. The electrochemichromic solution according to claim 1, wherein said cathodic compound is selected from the group of chemical compounds consisting of the following formulae:

##STR36## wherein R₂ and R₃ may be the same or different and each may be selected from the group consisting of H, any straight- or branched-chain alkyl constituent having from about one carbon atom to about six carbon atoms, or any straight- or branched-chain alkyl- or alkoxy-phenyl, wherein said alkyl or alkoxy constituent contains from about one carbon atom to about six carbon atoms;

X is selected from the group consisting of tetrafluoroborate, perchlorate, trifluoromethane sulfonate, hexafluorophosphate, any halide

and combinations thereof.

34. The electrochemichromic solution according to claim 33, wherein said cathodic compound is ##STR37##

35. The electrochemichromic solution according to claim 33, wherein said cathodic compound is ##STR38##

36. The electrochemichromic solution according to claim 33, wherein said cathodic compound is ##STR39##

37. The electrochemichromic solution according to claim 1, wherein said redox agent of (a) is in a solid form.

38. The electrochemichromic solution according to claim 37, wherein said redox agent has a particle size of about 50 mesh to about 400 mesh.

39. The electrochemichromic solution according to claim 1, wherein said redox agent of (a) is a reducing agent capable of causing an electrochemichromic compound to assume a decreased valence state upon contacting therewith as compared with that valence state possessed by said electrochemichromic compound prior to having been contacted with said reducing agent.

40. The electrochemichromic solution according to claim 39, wherein said reducing agent is a member selected from the group consisting of zinc, ascorbic acid, sodium hydrosulfite, vanadium (III) chloride, chromium (II) acetate, sulfur dioxide and any combination thereof.

41. The electrochemichromic solution according to claim 40, wherein said reducing agent is zinc.

42. The electrochemichromic solution according to claim 1, wherein said solvent of (c) is a member selected from the group consisting of acetonitrile, 3-hydroxypropionitrile, methoxypropionitrile, 3-ethoxypropionitrile, propylene carbonate, 2-acetylbutyrolactone, cyanoethyl sucrose, γ

-butyrolactone, 2-methylglutaronitrile, N,N'"'"'-dimethylformamide, 3-methylsulfolane, methylethyl ketone, cyclopentanone, cyclohexanone, benzoyl acetone, 4-hydroxy-4-methyl-2-pentanone, acetophenone, glutaronitrile, 3,3'"'"'-oxydipropionitrile, 2-methoxyethyl ether, triethylene glycol dimethyl ether and combinations thereof.

43. The electrochemichromic solution according to claim 1, wherein said solvent of (c) is acidic.

44. The electrochemichromic solution according to claim 43, wherein said solvent is rendered acidic by employing as a solvent component an acidic material selected from the group consisting of acetic acid, any hydrogen halide gas in solution, perchloric acid, 2-acetylbutyrolactone, 3-hydroxypropionitrile, benzoic acid in solution, ascorbic acid in solution and combinations thereof.

45. The electrochemichromic solution according to claim 44, wherein said solvent component is acetic acid.

46. The electrochemichromic solution according to claim 45, wherein said solvent component is acetic acid employed in the range of about 0.01% (v/v) to about 75% (v/v) .

47. The electrochemichromic solution according to claim 46, wherein said solvent component is acetic acid employed in the range of about 0.5% (v/v) to about 5% (v/v) .

48. The electrochemichromic solution according to claim 46, wherein said solvent component is acetic acid employed at about 3% (v/v).

49. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about 74% 3-hydroxypropionitrile, about 25% glutaronitrile and about 1% acetic acid (v/v).

50. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about 49.5% 3-hydroxypropionitrile, about 49.5% glutaronitrile and about 1% acetic acid (v/v).

51. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about propylene carbonate, about 35% cyanoethyl sucrose and about 1% acetic acid (v/v).

52. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about propylene carbonate, about 25% cyanoethyl sucrose and about 1% acetic acid (v/v).

53. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about 3-hydroxypropionitrite, 30% 3,3'"'"'-oxydipropionitrile and about 1% acetic acid (v/v).

54. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about propylene carbonate and about 1% acetic acid (v/v).

55. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about 99.5% propylene carbonate and about 0.5% acetic acid (v/v) .

56. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about propylene carbonate and about 2% acetic acid (v/v).

57. The electrochemichromic solution according to claim 44, wherein said solvent is comprised of about propylene carbonate and about 3% acetic acid (v/v).

58. The electrochemichromic solution according to claim 1, further comprising (d) a constituent selected from the group consisting of an ultraviolet stabilizing agent, an electrolytic material and combinations thereof.

59. The electrochemichromic solution according to claim 58, wherein said ultraviolet stabilizing agent is a member selected from the group consisting of "UVINUL 400", "UVINUL D-49", "UVINUL N-539", TINUVIN P", "TINUVIN 327", "TINUVIN 328", "CYASORB UV 24", acrylate and derivatives thereof, benzotriazole and derivatives thereof, benzophenone and derivatives thereof, and combinations thereof.

60. The electrochemichromic solution according to claim 59, wherein said ultraviolet stabilizing agent is "UVINUL 400".

61. The electrochemichromic solution according to claim 58, wherein said electrolytic material is a member selected from the group consisting of tetrabutylammonium hexafluorophosphate, tetraethylammonium perchlorate, tetrabutylammonium tetrafluoroborate, tetrabutylammonium trifluoromethane sulfonate, any halogen alkali metal salt and combinations thereof.

62. The electrochemichromic solution according to claim 61, wherein said electrolytic material is tetrabutylammonium hexafluorophosphate.

63. The electrochemichromic solution according to claim 1, wherein the total concentration of said anodic compound and said cathodic compound in said electrochemichromic solution is in the range of about 0.001M to about 0.1M.

64. The electrochemichromic solution according to claim 63, wherein the total concentration of said anodic compound and said cathodic compound in said electrochemichromic solution is about 0.04M.

65. The electrochemichromic solution according to claim 1, wherein said applied potential is introduced to said solution in the range of about 0.001 volts to about 5 volts.

66. The electrochemichromic solution according to claim 65, wherein said applied potential is introduced at about 1 volt to about 1.5 volts.

68. A process for using an electrochemichromic solution according to claim 1, said process comprising the steps of:

(a) inserting said electrochemichromic solution into a cell;

(b) sealing said cell so that said electrochemichromic solution is prevented from escaping therefrom; and

(c) introducing an applied potential to said electrochemichromic solution contained in said cell such that a current passes therethrough to cause a color change thereof.

69. An electrochemichromic device comprising:

(a) a first substantially transparent substrate coated with a substantially transparent conductive coating on its interior face;

(b) a second substantially transparent substrate coated with a substantially transparent conductive coating on its interior face, said second substrate positioned in substantially parallel spaced-apart relationship with said first substrate and being laterally displaced therefrom;

(c) a sealing means positioned toward the peripheral edge of each of said first substrate and said second substrate and sealingly forming a cell cavity therebetween;

(d) the electrochemichromic solution according to claim 1 having been dispensed into and confined within said cell cavity; and

(e) a means for introducing an applied potential to said electrochemichromic solution to controllably cause a variation in the amount of light transmitted through said device.

70. The electrochemichromic device according to claim 69, wherein said transparent conductive coating may be constructed from a material selected from the group consisting of indium tin oxide, indium tin oxide full wave, indium tin oxide half wave, indium tin oxide half wave green, tin oxide, antimony-doped tin oxide, fluorine-doped tin oxide, antimony-doped zinc oxide and aluminum-doped zinc oxide.

71. The electrochemichromic device according to claim 69, wherein said device is a member selected from the group consisting of mirrors, glazings, partitions, filters, displays and lenses.

72. The electrochemichromic device according to claim 71, wherein said glazing is a window assembly.

73. The electrochemichromic device according to claim 69, wherein said glazing is a sun roof assembly.

74. The electrochemichromic device according to claim 69, wherein said device is a mirror assembly further comprising a reflective coating on a face of either one of said first substrate or said second substrate.

75. The electrochemichromic mirror assembly according to claim 74, wherein said reflective coating is constructed of a material selected from the group consisting of aluminum, silver, platinum, palladium, titanium, chromium and stainless steel.

76. The electrochemichromic device according to claim 69, wherein said first substrate of (a) is a laminate assembly comprising at least two substantially transparent panels affixed to one another by a substantially transparent adhesive layer.

77. The electrochemichromic device according to claim 69, further comprising (g) a molded casing formed about the periphery of said device.

78. The electrochemichromic device according to claim 77, wherein said molded casing is constructed of injection molded polyvinyl chloride.

79. The electrochemichromic device according to claim 77, wherein said molded casing is constructed of a moldable material that is reaction injected molded.

80. The electrochemichromic device according to claim 69, wherein said sealing means of (c) may be constructed from a member selected from the group consisting of thermosetting materials and thermoplastic materials.

81. The electrochemichromic device according to claim 80, wherein said sealing means is constructed from a thermosetting material.

82. The electrochemichromic device according to claim 81, wherein said sealing means is constructed of a thermoplastic material.

83. The electrochemichromic device according to claim 69, wherein said first substrate of (a) and said second substrate of (b) are constructed from a material selected from the group consisting of glass, optical plastics, laminated glass and tempered glass.

84. The electrochemichromic device according to claim 69, wherein said first substrate of (a) and said second substrate of (b) are each constructed of the same material.

85. The electrochemichromic device according to claim 69, wherein said first substrate of (a) and second substrate of (b) are each constructed of different materials.

67. An electrochemichromic solution capable of color change when an applied potential is introduced thereto, said electrochemichromic solution comprising:

(a) a combination of anodic compounds, wherein at least one of said anodic compounds in said combination has been previously contacted with a redox agent such that said anodic compound exists in a different valence state than prior to having been contacted with said redox agent;

(b) at least one cathodic compound; and

(c) a solvent wherein the redox potential of said at least one of said anodic compounds in said combination in said different valence state is greater than the redox potential of said cathodic compound while each is contacted with said solvent.

86. An electrochemichromic device comprising:

(a) a first glass substrate coated with a conductive coating on its interior face;

(b) a second glass substrate coated with a conductive coating on its interior face, said second glass substrate positioned in substantially parallel spaced-apart relationship with said first glass substrate;

(c) a sealing means positioned toward, but inward from, the peripheral edge of each of said first substrate and said second substrate and sealingly forming a cell cavity therebetween;

(d) an electrochemichromic solution capable of color change when an applied potential is introduced thereto, said electrochemichromic solution comprising;

(1) an electrochemichromic compound selected from the group consisting of methylene violet (Bernthsen), 2-methyl-phenothiazin-3-one, phenothiazin-3-one and phenoxazin-3-one, wherein said compound has previously been reduced;

(2) a viologen salt; and

(3) a solvent, wherein said solvent is a member selected from the group consisting of the combination of 3-hydroxypropionitrile, glutraronitrile and acetic acid, the combination of propylene carbonate and acetic acid, the combination of 3-ethoxypropionitrile and 2-acetylbutyrolactone, the combination of 3-ethoxypropionitrile, glutaronitrile and acetic acid, the combination of 3-hydroxypropionitrile, 3,3'"'"'-oxydipropionitrile and acetic acid, and the combination of propylene carbonate, cyanoethyl sucrose and acetic acid, wherein said solution has been dispensed into and confined within said cell cavity; and

(e) a means for introducing an applied potential to said electrochemichromic solution to controllably cause a variation in the amount of light transmitted through said solution.

87. The electrochemichromic device of claim 86, further comprising after (d)(1):

(i) said previously reduced electrochemichromic compound having thereafter been isolated.

88. The electrochemichromic device according to claim 86, wherein said device is selected from the group consisting of mirrors, glazings, partitions, filters, displays and lenses.

89. The electrochemichromic device according to claim 88, wherein said device is a mirror further comprising a reflective coating on a face of said second glass substrate.

90. The electrochemichromic device according to claim 86, wherein said electrochemichromic compound is methylene violet (Bernthsen) and wherein the methylene violet (Bernthsen) has previously been reduced and thereafter isolated.