# US 11,079,647 B2 · Electrochromic display element, optical filter, lens unit, and imaging device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,647 B2 - Document ID: US11079647B2 - Status: Granted - Kind: B2 - Application number: 16/358,119 - Filed: 2019-03-19 - Published: 2019-09-26 - Granted: 2021-08-03 - Earliest claimed: 2018-03-22 - Assignees: Ricoh Company, Ltd. - Applicants: Naoki Ura; Fuminari Kaneko - Inventors: Naoki Ura; Fuminari Kaneko - Web page: https://patentgrep.com/patent/US11079647B2 ## CPC - G02F 1/1516: comprising organic material - C09K 9/02: Organic tenebrescent materials - G02F 1/1503: caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions - G02F 1/155: Electrodes - G03B 9/00: Exposure-making shutters; Diaphragms - G03B 11/00: Filters or other obturators specially adapted for photographic purposes - C09K 2211/1007: Non-condensed systems - C09K 2211/1014: bridged by heteroatoms, e.g. N, P, Si or B - C09K 2211/1018: Heterocyclic compounds - G02F 2001/15145: {the electrochromic layer comprises a mixture of anodic and cathodic compounds} - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) ## Abstract An electrochromic display element is provided. The electrochromic display element includes a pair of electrodes and an electrochromic layer disposed between the electrodes. The electrochromic layer contains a solvent, a supporting electrolyte, an anodic electrochromic molecule comprising a triarylamine derivative, and a cathodic electrochromic molecule comprising a viologen derivative. Concentrations of the triarylamine derivative and the viologen derivative in the electrochromic layer are each 4 mM or more. ## Claims ### Claim 1 An electrochromic display element comprising: a pair of electrodes; and an electrochromic layer disposed between the electrodes, the electrochromic layer containing: a solvent; a supporting electrolyte: an anodic electrochromic molecule comprising a triarylamine derivative; and a cathodic electrochromic molecule comprising a viologen derivative, wherein concentrations of the triarylamine derivative and the viologen derivative in the electrochromic layer are each 4 mM or more, and wherein the viologen derivative comprises a compound represented by the following general formula (5): where each of R1 and R2 independently represents an alkyl or aryl group having 1 to 10 carbon atoms which may have a substituent; each of n and m independently represents 0 or an integer of from 1 to 10; and X represents a monovalent anion selected from the group consisting of ClO4 ion (ClO4-), PF6 ion (PF6-), BF4 ion (BF4-), CF3SO3 ion (OTf-), (FSO2)2N ion (FSI-), (CF3SO2)2N ion (TFSI-), or B(CN)4 ion (TCB-). ### Claim 2 The electrochromic display element according to claim wherein the concentrations of the triarylamine derivative and the viologen derivative in the electrochromic layer are each 8 mM or more. ### Claim 3 (depends on 2) The electrochromic display element according to claim 2, wherein the concentrations of the triarylamine derivative and the viologen derivative in the electrochromic layer are each 11 mM or more. ### Claim 4 The electrochromic display element according to claim wherein the triarylamine derivative comprises a benzidine derivative. ### Claim 5 (depends on 4) The electrochromic display element according to claim 4, wherein the benzidine derivative comprises a compound represented by the following general formula (6): where each of R55 to R58 independently represents a halogen atom, an alkyl group, an alkoxy group, or a phenyl ether group; each of R59 to R66 independently represents a hydrogen atom, an alkyl group, or an alkoxy group; and each of R67 and R68 independently represents a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group, or R67 and R68 may be bonded with each other to form the following structure when each of R67 and R68 represents an alkyl group: where each of R1 and R2 independently represents an alkyl group or an aryl group. ### Claim 6 (depends on 1) The electrochromic display element according to claim 1, wherein the triarylamine derivative comprises a compound represented by the following general formula (7): where each of R1 to R3 independently represents at least one member selected from the group consisting of a halogen atom, an alkyl group, an alkoxy group, a group in which an aryl group and a heterocyclic group are bonded via a covalent bond, and a group in which an aryl group and a heterocyclic group are ring-condensed; and each of R4 to R15 independently represents at least one member selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a group in which an aryl group and a heterocyclic group are bonded via a covalent bond, acid a group in which an aryl group and a heterocyclic group are ring-condensed. ### Claim 7 (depends on 1) The electrochromic display element according to claim 1, wherein the viologen derivative comprises a compound represented by one of the following structural formulae (4) to (7). ### Claim 8 (depends on 1) The electrochromic display element according to claim 1, wherein the solvent comprises a benzonitrile derivative. ### Claim 9 (depends on 1) An optical filter comprising the electrochromic display element according to claim 1. ### Claim 10 (depends on 9) The optical filter according to claim 9, further comprising an active element coupled to the electrochromic display element. ### Claim 11 (depends on 1) A lens unit comprising the electrochromic display element according to claim 1. ### Claim 12 (depends on 1) An imaging device comprising: an imaging optical system comprising an optical path; and the electrochromic display element according to claim 1 disposed in the optical path.