Variable light transmittance glass board functional as electrochromic cell
US4801195A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1985 |
| Grant date | Jan 31, 1989 |
| Priority date | — |
| Expiry date | Dec 19, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2001/1517
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention relates to a variable light transmittance glass board which is an electrochromic cell in principle and is comprised of oppositely arranged two transparent glass substrates each of which is laid with a transparent electrode film, first and second electrochromic layers formed on the two electrode films, respectively, by using tungsten trioxide for the first layer and Prussian blue for the second layer and an electrolyte liquid which fills up the space remaining between the two electrode films. The electrolyte liquid is a solution of a conventional supporting electrolyte such as lithium perchlorate in an organic polar solvent such as propylene carbonate. Durability of both electrochromic layers at elevated temperatures is greatly improved by adding 0.2-3.0 wt % of water to the organic polar solvent. By using one or two auxiliary electrode(s) comprising an electrochemically oxidizable and reducible material and being disposed in a marginal region of the space between the two glass substrates, it is possible to prevent the appearance of the glass board from being marred by partial decomposition of the electrolyte liquid at the initial reduction of one electrochromic layer.…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.