Electrochromic devices

Claim 2

An electrochromic device comprising: a case having a transparent face and a light-coloured face opposite thereto which is capable of highlighting the display colours of the device during the write cycle; a display electrode within said case and adjacent said transparent face, said display electrode comprising a transparent conductive electrode and a display polymer film attached thereto, said display polymer film comprising a linear tractable electroactive polymer which is capable of undergoing reversible oxidation, reversible reduction or both to form a linear charged, coloured polymer incorporating charge-compensating ionic dopants, said polymer comprising diradical repeat units selected from a heterocyclic ring system including at least one Group 5B or Group 6B heteroatom, wherein none of the ring carbon atoms are saturated, a heterocyclic ring system including at least one Group 5B or Group 6B heteroatom wherein none of the ring carbon atoms are saturated and a connecting unit, and mixtures thereof, said diradical repeat unit being in the form of a monomeric repeat unit which is capable of undergoing reversible oxidation, reversible reduction or both to form a stable ionic species and said connecting unit being a conjugated system or atom or group of atoms which maintain K -orbital overlap with the heterocyclic ring system; a counter electrode adjacent to said light-coloured face; an electrolyte solution comprising a solvent containing ionic dopants; and means for applying a voltage and current to said display electrode and said counter electrode.

Claim 3

An electrochromic device as claimed in Claim 1, wherein said display polymer Group 5B or 6B heteroatom is N, P, As, 0, S, Se, Te or a mixture thereof and none of the heteroatoms occupies the ring fusion positions and the P, As, 0, S, Se and Te atoms do not occupy adjacent ring positions.

Claim 4

An electrochromic device as claimed in Claim 2, wherein said heteroatom is N, S, 0, or a mixture thereof.

Claim 5

An electrochromic device as claimed in Claim 3, wherein the heteroatom is nitrogen and no more than two nitrogen atoms are bonded sequentially within the heterocyclic ring system.

Claim 6

An electrochromic device as claimed in Claim 3, wherein the diradicals are positional diradicals selected from thianthrenes; phenoxathiins; phenoxazine; N-alkylphenothiazine; dihydrophenazine; dialkyldihydrophenazine; dibenzodioxin; benzoxazole; benzothiazole; benzoselenazole; N-alkyl-substituted benzimidazole; 1,7-dimethyl-benzo[1,2,-d:4,5-d']diimidazole; benzo[1,2-d:5,4-d']bisthiazole; benzo[1,2-d:4,5-d']bisthiazole; benzo[1,2-d:4,5-d']bis-selenazole; benzo[1,2-d:5,4-d']bis-selenazole; benzo[1,2-d:4,5-d']bistellurazole; selenazole[5,4-f]benzothiazole; 1,8-dialkyl-benzo[1,2-d:3,4-d']diimidazole; benzo[1,2-d:5,4-d'[bisoxazole; benzo[1,2-d:4,5-d')bisoxazole; benzo[1,2-d:3,4-d']bisoxazole; benzo[1,2-d:3,4-d']bis-thiazole; triazole and 1,4-phenylene; thiadiazole and 1,4-phenylene; oxadiazole and 1,4-phenylene; oxazole and 1,4-phenylene; thiazole and 1,4-phenylene; cinnoline; quinazoline; quinoxaline; 2-phenylquinoxaline; 4-phenylquinoline; phthalazine; 1,5-naphthyridine; 1,6-naphthyridine; 1,7-naphthyridine; 1,8-naphthyridine; 2,6-naphthyridine; copyrine; 1,2,4-benzotriazine; pyrido[3,2-d]pyrimidine; pyrido[4,3-d]pyrimidine; pyrido[3,4-d]pyrimidine; pyrido[2,3-d]pyrimidine; pyrido[2,3-b]pyrazine; pyrido[3,4-b]pyrazine; pyrido[2,3-d]pyridazi,ne; pyrido[3,4-d]pyridazine; pyridazino[4,5-c]pyridazine; pyrimido[5,4-d]pyrimidine; pteridine; pyrimido[4,5-d]pyridazine; pyrimido[4,5-d]pyrimidine; pyrazino[2,3-b]pyrazine; pyrazino[2,3-d]pyridazine; pyridazino[4,5-d]pyridazine; pyrimido[4,5-c]pyridazine; pyrazino[2,3-c]pyridazine; pyrido[3,2-d]-as-triazine; pyrimido[4,5-e]-as-triazine; pyrido[2,3-e]-as-triazine; and as-triazino-[6,5-d]-as-triazine; and mixtures of these diradicals.

Claim 7

An electrochromic device as claimed in Claim 3, wherein said polymer comprises diradical repeat units selected from the positional diradicals of quinoline, isoquinoline and quinoxaline, said diradicals being interspersed with connecting units, substituted derivatives thereof, or mixtures thereof.

Claim 8

An electrochromic device as claimed in Claim 6, wherein the polymer is selected from: wherein Z is a connecting unit or nothing; and wherein n is the degree of polymerization.

Claim 9

An electrochromic device as claimed in Claim 6, wherein the display polymer has the following formula: wherein R iii is a substituent group selected from H,.alkyl of 1 to 4 carbons, alkoxy'of 1 to 4 carbon atoms, an alkylthio. of 1 to 4 carbon atoms, a cycloaliphatic group of 5 or 6 carbon atoms, an alkenyl group of 2 to 4 carbon atoms, an aryl group of 6 to 10 carbon atoms, an aryl group of 6 to 10 carbon atoms substituted by 1 to 3 alkyl groups of 1 to 4 carbon atoms, alkenyl groups of 1 to 4 carbon atoms, alkynyl groups of 1 to 4 carbon atoms, alkoxy groups of 1 to 4 carbon atoms, 1 to 3 cyano groups, 1 to 3 halogen atoms, dialkyl amino groups of 1 to 4 carbon atoms, an alkylthiol of 1 to 4 carbon atoms, or a 5- or 6-member, nitrogen-containing, unsaturated heterocyclic group; and R vii is H or CH 3 .

Claim 10

An electrochromic device as claimed in Claim 3, wherein the polymer is selected from poly-2,2'-(p-phenylene)-1,1'-dimethyl-5,5'-bibenzimidazole; poly-2,2'-(p-phenylene')-5,5'-bibenzoxazole; poly-2,2'-(p-phenylene)-5,5'-bibenzothiazole; poly-2,6-(p-phenylene)-benzo[1,2-d:5,4-d']bisoxazole; poly-2,6-(p-phenylene)-1,7-dimethyl-benzo[1,2-d:4,5-d']diimidazole; poly-2,6-(p-phenylene)-benzo[1,2-d:4,5-d']bisthiazole; poly-2,6-(m-phenylene)benzo[1,2-d:4,5-d']bisthiazole; poly-1,4-phenylene-2,5-(1,3,4-oxadizole); copolymer of oxadiazole and thiadiazole with 1,4-phenylene connecting units; copolymer of oxadiazole and thiadiazole; poly-1,4-phenylene-2,5-(1,3,4-thiadiazole); poly-l,4-phenylene-2,4-(1,3-thiazole); poly-1,4-phenylene-2,5-(1-phenyl-1,3,4-triazole); poly-1,4-phenylene-2,5-(1,4-dithiin); poly-2,6-(4-phenylquinoline); poly-2,6-(4-phenylquinoline) plus a connecting unit; poly-2,2'-(m-phenylene)-6,6'-bibenzoxa- zole; poly-2,2'-(m-phenylene)-1,1'-dimethyl-6,6'- bibenzimidazole; poly-2,2'-(m-phenylene)-6,6'-bibenzo- thiazole; poly-2,2'-(N-methyl-p,p'-aminodiphenylene)-6,6'- bibenzoxazole; poly-2,5-phenoxazine; poly-2,5'-(3,7-dimethyl)phenoxazine; poly-2,5-(1,4-phenylene)phenoxazine; poly-3,7-(N-methylphenothiazine)-2,5-(1,3,4-oxadiazole); poly-3,7-(phenoxathiin -4,4'-dithiobiphenylene); poly-(1,4-dithiophenylene-2,6-thianthrene); poly-4,4'-N-methyl-aminodiphenylene-2,5-(1,3,4-oxadiazole); poly-2,2'-(p-phenylene)-6,6'-bibenzoxazole; poly-2,2'-(p-phenylene)-6,6'-bibenzothiazole; and poly-2,2'-(p-phenylene)-1,1'-dimethyl-6,6'-bibenzimidazole.

Claim 11

An electrochromic device as claimed in Claim 3, wherein said means for applying a current and voltage biases the display electrode to reducing conditions and the display polymer is selected from poly-2,2'-(p-phenylene)-1,l'-dimethyl-5,5'-bibenzimidazole; poly-2,2'-(p-phenylene)-5,5'-bibenzoxazole; poly-2,2'-(p-phenylene)-5,5'-bibenzothiazole; poly-2,6-(p-phenylene)-benzo[1,2-d:5,4d']bisoxazole; poly-2,6-(p-phenylene)-1,7-dimethyl-benzo[1,2-d:4,5d']diimidazole; poly-2,6-(p-phenylene)-benzo[1,2-d:4,5-d']bisthiazole; poly-2,6-(m-phenylene)benzo[1,2-d:4,5-d']bisthiazole; poly-1,4-phenylene-2,5-(1,3,4-oxadiazole); copolymer of oxadiazole and thiadiazole'with 1,4 phenylene connecting units; copolymer of oxadiazole and thiadiazole; poly-1,4-phenylene-2,5-(1,3,4-thiadiazole); poly-l,4-phenylene-2,4-(1,3-thiazole); poly-l,4-phenylene-2,5-(l-phenyl-l,3,4-triazole); poly-l,4-phenylene-2,5-(l,4-dithiin); poly-2,6-(4-phenylquinoline); poly-2,6-(4-phenylquinoline) plus a connecting unit; poly-2,6-[4-(4'-chlorophenyl)quinoline]; and poly-2,6-[4-(4'-methoxyphenyl)quinoline].

Claim 12

An electrochromic device according to Claim 3, wherein said means for applying a current and voltage biases the display electrode to oxidizing conditions and said display polymer is selected from poly-2,2'-(m-phenylene)-6,6'-bibenzoxazole; poly-2,2'-(m-phenylene)-1,1'-dimethyl-6,6'-bibenzimidazole; poly-2,2'-(m-phenylene)-6,6'-bibenzothiazole; poly-2,2'-(N-methyl-p,p'-aminodiphenylene)-6,6'-bibenzoxazole; poly-2,5-phenoxazine; poly-2,5'-(3,7-dimethyl)phenoxazine; poly-2,5-(1,4-phenylene)phenoxazine; poly-3,7-(N-methylphenothiazine)-2,5-(1,3,4-oxadiazole; poly-3,7-(phenoxathiin-4,4'-dithiobiphenylene; poly-(1,4-dithiophenylene-2,6-thianthrene); and poly-4,4'-N-methyl- aminodiphenylene-2,5-(1,3,4-oxadiazole).

Claim 13

12 . An electrochromic device as claimed in Claim 3, wherein the display polymer is a polymer selected from poly-2,2'-(m-phenylene)-6,6'- bibenzoxazole; poly-2,2 1- (m-phenylene)-1,1'-dimethyl-6,6 1- bibenzimidazole; poly-2,2'-(m-phenylene)-6,6'-bibenzothia- zole; poly-2,2'-(N-methyl-p,p'-aminodiphenylene)-6,6'- bibenzoxazole; poly-2,5-phenoxazine; poly-2,5'-(3,7-dimethyl)phenoxazine; poly-2,5-(1,4-phenylene)phenoxazine; poly-3,7-(N-methylphenothiazine)-2,5-(1,3,4-oxadiazole; poly-3,7-(phenoxathiin-4,4'-dithiobiphenylene; poly-(1,4-dithiophenylene-2,6-thianthrene); poly-4,4'-N-methyl- aminodiphenylene-2,5-(1,3,4-oxadiazole); poly-2,2'-(p-phenylene)-6,6'-bibenzoxazole; poly-2,2'-(p-phenylene)-6,6'-bibenzothiazole; and poly-2,2'-(p-phenylene)-1,1'-dimethyl-6,6'-bibenzimidazole.

Claim 14

An electrochromic device as claimed in Claim 3, wherein the display electrode and counter electrode contain display polymers.

Claim 15

An electrochromic device as claimed in Claim 13, wherein the display polymers are reversible n-type and p-type display polymers selected from poly-2,2'-(p-phenylene)-6,6'-bibenzoxazole; poly-2,2'-(p-phenylene)-6,6'-bibenzothiazole; and poly-2,2'-(p-phenylene)-1,1'-dimethyl-6,6'-bibenzimidazole.

Claim 16

An electrochromic device according to Claim 3, wherein the display polymer in its coloured form and associated with compensating ionic dopants has the general formula: wherein a is 0 or 1; b is 0 or 1; c is 0 or 1; n is an integer from 2 to 2000; d is an integer from 1 to 4000; S is an integer 1, 2, or 3; R is a diradical of an unsaturated heterocyclic ring system containing at least one Group 5B or 6B heteroatom, wherein none of the ring carbon atoms is saturated; R' is the same diradical as R or a different diradical unsaturated heterocyclic ring system; X is a diradical connecting unit; Y is the same diradical connecting unit as X or a different diradical connecting unit; and M is a charge-compensating ionic dopant of opposite electrical charge to the charge of the polymer backbone, wherein the polymer backbone is capable of undergoing reversible oxidation or reversible reduction or both to form a linear charged polymer backbone, said diradical or diradical-connecting unit in the form of a monomeric repeat unit being capable of undergoing reversible oxidation or reversible reduction or both to form a stable ionic species, and wherein R and R' contain no exocyclic double bonds, and wherein said connecting unit is a conjugated system or atom or group of atoms which maintain x-orbital overlap with the heterocyclic ring system.

Claim 17

An electrochromic device a ' s claimed in Claim 15, wherein said means for applying a current and voltage produces at least two separate colours in the display polymer during the write cycle.

Claim 18

An electrochromic device as claimed in any preceding claim, wherein said counter electrode is composed of Pt, Au, or Ag/Ag halide.

Claim 19

An electrochromic device as claimed in any preceding claim, wherein the electrolyte solution comprises a solvent selected from acetonitrile; polypropylene carbonate; tetrahydrofuran; propionitrile; butyronitrile; phenylacetonitrile; dimethylformamide, dimethoxyethane; dimethylsulfoxide; pyridine; and mixtures thereof.

Claim 20

An electrochromic device as claimed in any preceding claim, wherein the electrolyte solution contains a supporting electrolyte which is a salt.having a cation- anion pair wherein the cations are selected from Li + , Na + , K + , Cs + , Mg ++ , (CH 3 ) 4 N +, (C 2 H 5 ) 4 N + , (C 3 H 7 ) 4 N + and (C 4 H 9 ) 4 N + , and the anions are selected from F , Cl , Br - , I - , ClO 4 - , BF 4 - , PF 6 - , AsF6 and NO 3 - .

Claim 21

An electrochromic device as claimed in Claim 1, wherein the counter electrode comprises silver coated with silver halide and the display electrode comprises poly-2,6-(4-phenylquinoline).