Electrochromic display devices
First Claim
1. In an electrochromic display device which comprises a unit cell having a pair of electrodes spaced from each other, at least one of which is transparent and serves as a display electrode, a means for applying a potential across the cell for reversing the electrode polarity, an electrochromic solution filled in the cell, and an optical diffuser means disposed between the paired electrodes to provide a white background, the improvement wherein said electrochromic solution comprises, in an inert solution, an electrolyte and a diphenylamine compound which is capable of electrochemically reversible color formation and erasure, said diphenylamine compound being represented by the following general formula ##STR3## in which R1 represents a hydrogen atom, unsubstituted or substituted alkyl group, or unsubstituted or substituted aralkyl, and R2, R3, R4 and R5 independently represent a hydrogen atom, unsubstituted or substituted alkyl, unsubstituted or substituted aralkyl group, unsubstituted or substituted aryl group, and cycloalkyl group.
1 Assignment
0 Petitions
Accused Products
Abstract
An electrochromic display devices using a specific type of diphenylamine as an electrochromic material is described. The diphenylamine compound, which is dissolved in an inert solvent along with an electrolyte, can undergo electrochemically reversible color formation and erasure reactions and form two different colors at one of electrodes on application of two different potentials across the electrodes. Multicolor devices are also described in which the diphenylamine compound capable of forming colors by oxidation is used in combination with an anthraquinone compound which is capable of forming a color, different from the colors of the oxidized species of the diphenylamine coumpound, at the same electrode by reduction.
-
Citations
22 Claims
- 1. In an electrochromic display device which comprises a unit cell having a pair of electrodes spaced from each other, at least one of which is transparent and serves as a display electrode, a means for applying a potential across the cell for reversing the electrode polarity, an electrochromic solution filled in the cell, and an optical diffuser means disposed between the paired electrodes to provide a white background, the improvement wherein said electrochromic solution comprises, in an inert solution, an electrolyte and a diphenylamine compound which is capable of electrochemically reversible color formation and erasure, said diphenylamine compound being represented by the following general formula ##STR3## in which R1 represents a hydrogen atom, unsubstituted or substituted alkyl group, or unsubstituted or substituted aralkyl, and R2, R3, R4 and R5 independently represent a hydrogen atom, unsubstituted or substituted alkyl, unsubstituted or substituted aralkyl group, unsubstituted or substituted aryl group, and cycloalkyl group.
-
5. In an electrochromic display device which comprises a unit cell having a pair of electrodes spaced from each other, at least one of which is transparent and serves as a display electrode, a means for applying a potential across the cell and for reversing the electrode polarity, an electrochromic solution filled in the cell, and an optical diffuser means provided between the paired electrodes to provide a white background so as to permit formation of a clear color at one of the electrodes while preventing visual observation of another color formed at the other electrode, the improvement wherein said electrochromic solution comprises, in an inert solution, an electrolyte and a mixture of (1) a diphenylamine compound, which is capable of electrochemically reversible color formation and erasure at the display electrode at one electrode polarity and is able to form two different colors on application of different potentials across the cell, and (2) an electrochromic compound which is able to form a color by reduction, and which is capable of electrochemically reversible color formation and erasure at the display electrode at the other electrode polarity and is able to form a color different from the two colors,
said diphenylamine compound being represented by the following general formula ##STR4## in which R1 represents a hydrogen atom, unsubstituted or substituted alkyl group, or unsubstituted or substituted aralkyl, and R2, R3, R4 and R5 independently represent a hydrogen atom, unsubstituted or substituted alkyl, unsubstituted or substituted aralkyl group, unsubstituted or substituted aryl group, and cycloalkyl group.
- 12. In an electrochromic display device which comprises a unit cell having a pair of electrodes spaced from each other, at least one of which is transparent and serves as a display electrode, a means for applying a potential across the cell for reversing the electrode polarity, an electrochromic solution filled in the cell, and an optical diffuser means disposed between the paired electrodes to provide a white background, the improvement wherein said electrochromic solution comprises, in an inert solution, an electrolyte and a diphenylamine compound which is capable of electrochemically reversible color formation and erasure, wherein said diphenylamine compound is a member selected from the group consisting of 4,4'"'"'-bis(dimethylamino)diphenylamine, 4,4'"'"'-bis(dimethylamino)-N-methyldiphenylamine, 4,4'"'"'-bis-(isopropylamino)diphenylamine, 4,4'"'"'-bis(phenylamino)diphenylamine, 4-(dimethylamino-4'"'"'-(isopropylamino)-N-methyldiphenylamine, 4,4'"'"'-bis(cyclohexylamino)-N-methyldiphenylamine, and 4-(dimethylamino)-4'"'"'(1-methylhexylamino)diphenylamine.
-
17. In an electrochromic display device which comprises a unit cell having a pair of electrodes spaced from each other, at least one of which is transparent and serves as a display electrode, a means for applying a potential across the cell and for reversing the electrode polarity, and electrochromic solution filled in the cell, and an optical diffuser means provided between the paired electrodes to provide a white background so as to permit formation of a clear color at one of the electrodes while preventing visual observation of another color formed at the other electrode, the improvement wherein said electrochromic solution comprises, in an inert solution, an electrolyte and a mixture of (1) a diphenylamine compound, which is capable of electrochemically reversible color formation and erasure at the display electrode at one electrode polarity and is able to form two different colors on application of different potentials across the cell, and (2) am electrochromic compound which is able to form a color by reduction, and which is capable of electrochemically reversible color formation and erasure at the display electrode at the other electrode polarity and is able to form a color different from the two colors, and
wherein said diphenylamine compound is a member selected from the group consisting of 4,4'"'"'-bis(dimethylamino)-diphenylamine, 4,4'"'"'-bis(dimethylamino)-N-methyldiphenylamine, 4,4'"'"'-bis-(isopropylamino)diphenylamine, 4,4'"'"'-bis(phenylamino)diphenylamine, 4-(dimethylamino)-4'"'"'-(isopropylamino)-N-methyldiphenylamine, 4,4'"'"'-bis-(cyclohexylamino)-N-methyldiphenylamine, and 4-(dimethylamino)-4'"'"'(1-methylhexylamino)-diphenylamine.
Specification