Electrochromic organic polymer synthesis and devices utilizing electrochromic organic polymers
US6747780B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 25, 2002 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Aug 22, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K85/1135
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Large contrast ratio and rapid switching laminated electrochromic (EC) polymer device includes transparent electrode, cathodic EC polymer, gel electrolyte, and counter-electrode. Preferably the cathodic EC polymer is a poly(3,4-propylenedioxythiophene) derivative, PProDOT-Me2. Counter-electrode is a conductive coating deposited on transparent substrate, with preferred coatings including gold and highly conductive carbon. Lithography and sputtering can be employed to pattern a gold layer, while screen printing can be employed to similarly pattern graphite. Empirical studies of preferred device indicate a color change of high contrast ratio of transmittance (>50% T) is rapidly (0.5-1s) obtained upon applied 2.5V, repeatable to at least 10,000 times, as estimated by electrochemistry. Dual layer EC devices including PProDOT-Me2 are also disclosed, as are methods for synthesizing preferred EC polymers. Preferred synthesis method for obtaining PProDOT-Me2 involves refluxing reagents in toluene in the presence of catalyst, while continually removing methanol byproduct from refluxing solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.