US4726664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrochromic device
Assignee: Nippon Sheet Glass Co Ltd
•
Filing: 1986-03-24
•
Granted: 1988-02-23
•
Expires: 2006-03-24
Abstract
Abstract An electrochromic device comprising an oxidation coloring substance coloring in an oxidized state and a reduction coloring substance coloring in a reduced state which are formed on the surfaces of a pair of electrodes, respectively, and an electrolyte held between the two substances, wherein the oxidation coloring substance is a double salt containing an iron hexacyanoferrate and the reduction coloring substance is a tungsten-oxalic acid compound. The electrochromic device has a long life suitable for actual applications and a short response time and can operate at low applied voltages.
Inventors
- 👤 Hiroaki Tada
- 👤 Hirotsugu Nagayama
- 👤 Hideo Kawahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:30
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/1514; G02F1/1523; G02F1/1524; G02F1/1516; G02F2001/1517; G02F1/153; G02F1/155; G02F2001/1557
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
69 words
An electrochromic device comprising an oxidation coloring substance coloring in an oxidized state and a reduction coloring substance coloring in a reduced state which are formed on the surfaces of a pair of electrodes, respectively, and an electrolyte held between the oxidation and reduction coloring substances, wherein the oxidation coloring substance is a double salt containing an iron hexacyanoferrate and the reduction coloring substance is a tungsten-oxalic acid compound.
Claim 2
Dependent Claim
69 words
An electrochromic device comprising an oxidation coloring substance coloring in an oxidized state and a reduction coloring substance coloring in a reduced state which are formed on the surfaces of a pair of electrodes, respectively, and an electrolyte held between the oxidation and reduction coloring substances, wherein the oxidation coloring substance is a double salt containing an iron hexacyanoferrate and the reduction coloring substance is a tungsten-oxalic acid compound.
Claim 3
Dependent Claim
39 words
An electrochromic devide according to claim 1, wherein the tungsten-oxalic acid compound contains oxalic acid coordinating with tungsten, the weight of said oxalic acid being 0.172 to 0.48 times the weight of the tungsten in the tungsten-oxalic acid compound.
Claim 4
Dependent Claim
33 words
An electrochromic device according to claim 1 or 2, wherein the electrolyte contains at least one cation species selected from the group consisting of potassium ion, rubidium ion, cesium ion and ammonium ion.
References Cited (Backward Citations)
US3941849A
Cited
JPS5148994A
Cited
JPS5311177A
Cited
US4182551A
Cited
US4211475A
Cited
US4390246A
Cited
JPS564679A
Cited
US4338000A
Cited
US4411497A
Cited
US4465339A
Cited
US4451348A
Cited
US4513302A
Cited
JPS59154425A
Cited
JPS59155833A
Cited
US4645307A
Cited
US4652090A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |