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US4693564A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrochromic display device

Assignee: Sony Corp
•
Filing: 1985-10-30
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Granted: 1987-09-15
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Expires: 2005-10-30
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Abstract

Abstract An electrochromic display device which comprises a pair of electrodes, at least one of which is a transparent display electrode and which are spaced from each other and an electrochromic solution placed inbetween the paired electrodes in contact therewith. The electrochromic solution is an aqueous solution comprising an N,N'-di(p-cyanophenyl)-4,4'-bipyridinium dihalide serving as an active substance, an alkali ferrocyanide as an ancillary redox material and an electrolyte. The electrolyte is a mixture of a hypophosphite ion, and a salt corresponding to the anion of the active substance and the alkali ion of the ancillary redox material. These materials have, respectively, certain ranges of molar concentrations.

Inventors

  • 👤 Hiroshi Mori

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 15:53
CPC Classifications
C; C09; C09K; C09K9/00; C09K9/02; G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/1503

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 134 words
An electrochromic display device which comprises a cell having facing electrodes, at least one of which is a display electrode and which are spaced from each other, and an electrochromic solution filled between and in contact with the paired electrodes in a sealed manner, said electrochromic solution comprising an aqueous solution of an N,N'-di(p-cyanophenyl)-4,4'-bipyridinium dihalide as an active substance, an alkali ferrocyanide as an auxiliary redox material, and an electrolyte consisting of a hypophosphite ion and a salt corresponding to the salt obtained from the anion of the active substance and the alkali ion of the auxiliary redox material, said active substance being used in an amount of 0.005 to 0.035 M, said hypophosphite being used in an amount not less than 0.5M, said salt being used in an amount not less than 0.25M.
Claim 2
Dependent Claim 134 words
An electrochromic display device which comprises a cell having facing electrodes, at least one of which is a display electrode and which are spaced from each other, and an electrochromic solution filled between and in contact with the paired electrodes in a sealed manner, said electrochromic solution comprising an aqueous solution of an N,N'-di(p-cyanophenyl)-4,4'-bipyridinium dihalide as an active substance, an alkali ferrocyanide as an auxiliary redox material, and an electrolyte consisting of a hypophosphite ion and a salt corresponding to the salt obtained from the anion of the active substance and the alkali ion of the auxiliary redox material, said active substance being used in an amount of 0.005 to 0.035 M, said hypophosphite being used in an amount not less than 0.5M, said salt being used in an amount not less than 0.25M.
Claim 3
Dependent Claim 40 words
An electrochromic display device according to claim 1, wherein said facing electrodes are each formed on a glass substrate and said display electrode has an insulative masking layer which has been removed according to a desired pattern to be displayed.
Claim 4
Dependent Claim 15 words
An electrochromic display device according to claim 1, wherein said active substance is N,N'-di(p-cyanophenyl)-4,4'-bipyridinium dichloride.
Claim 5
Dependent Claim 15 words
An electrochromic display device according to claim 1, wherein said active substance is N,N'-di(p-cyanophenyl)-4,4'-bipyridinium dibromide.
Claim 6
Dependent Claim 20 words
An electrochromic display device according to claim 1, wherein the hypophosphite ion is derived from sodium hypophosphite or potassium hypophosphite.
Claim 7
Dependent Claim 17 words
An electrochromic display device according to claim 1, wherein said salt is sodium chloride or potassium chloride.
Claim 8
Dependent Claim 21 words
An electrochromic display device according to claim 1, wherein the hypophosphite ion is used in amounts up to a saturation thereof.
Claim 9
Dependent Claim 20 words
An electrochromic display device according to claim 1, wherein said salt is used in amounts up to a saturation thereof.

References Cited (Backward Citations)

US3712709A Cited
US4060311A Cited
US4116535A Cited
US4326777A Cited
US4376569A Cited
US4473695A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-09-14 1991-03-16 1991-09-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-09-14 1995-03-16 1995-09-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-09-14 1999-03-16 1999-09-15 $7700.00 Window Closed / Lapsed

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