| 摘要 |
<p>The invention relates to a picture display cell with memory effect in which a 4,4'-bipyridinium compound is used as a reduceable redox material. According to the invention said redox material is dissolved in a cell medium which contains a mixture of water and an electrochemically inert organic solvent. A suitable organic solvent is, for example, dimethyl sulphoxide. Herewith it is achieved that crystallization of constituents of the medium takes place only at temperature far below 0.degree.C so that the picture display cell can also be used at lower temperatures. The 4,4'-bipyridinium compound may be chosen to be so that the resulting picture can be erased directly electrochemically without the use of an auxiliary couple.</p> |
