Single-compartment, self-erasing, solution-phase electrochromic devices, solutions for use therein, and uses thereof

Claim 2

A solution, for use as the variable transmittance medium in a single-compartment, self-erasing, solution-phase electrochromic device, which comprises (A) a solvent; (B) at least one cathodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible reduction waves, with the first of said reductions accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; (C) at least one anodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible oxidation waves, with the first of said oxidations accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; and (D) if all cathodic and anodic compounds in their zero-potential equilibrium states in the solution are not ionic, an inert current-carrying electrolyte.

Claim 3

A solution according to Claim 1 wherein: (A) the solvent is liquid at room temperature and selected from propylene carbonate, gamma-butyrolactone, gamma-valerolactone, and any homogeneous mixture that is liquid at room temperature of any two or more of said solvents or any one or more of said solvents with ethylene carbonate; (B) the cathodic compounds are selected from (i) compounds of Formula II wherein R 21 and R22 are the same or different and are each selected from alkyl of 1 to 10 carbon atoms, phenyl optionally substituted at any one position with chloride, bromide, iodide, cyano, or an alkyl group of 1 to 4 carbon atoms, and benzyl, wherein the phenyl group is optionally substituted at any one position with chloride, bromide, iodide, cyano, or an alkyl group of 1 to 4 carbon atoms; and wherein X 3 and X 4 are the same or different and are each selected from chloride, bromide, iodide, BF¢ , PF - 6 . AsF - 6 , ClO - 4 and N O - 3 ; and (ii) compounds of Formula III wherein R 21 and R 22 are the same or different and are defined as above for the compound of Formula II, R 3 , is alkylene of 1 to 10 carbon atoms, and X 1 , X 2 , X 3 3 and X 4 are the same or different and each selected from chloride, bromide, iodide, BF - 4 , PF6 , AsF - 6 , ClO - 4 and NO - 3 ; (C) the anodic compounds are selected from (i) compounds of Formula IV wherein R 41 , R 42 , R 43 and R 44 are the same or different and are each selected from hydrogen, alkyl of 1 to 10 carbon atoms, phenyl optionally substituted at any one position with chloride, bromide, iodide, cyano, or an alkyl group of 1 to 4 carbon atoms, and benzyl, wherein the phenyl moiety is optionally substituted at any one position with chloride, bromide, iodide, cyano, or an alkyl group of 1 to 4 carbon atoms; (ii) compounds of the Formula V wherein R s , and R 54 are the same or different and are each selected from hydrogen and dialkylamino, wherein the alkyl groups are the same or different and are each of 1 to 6 carbon atoms; R 52 is oxygen, sulfur or NR ss , wherein R ss is the same as or different from R S3 and both R ss and R 53 are selected from hydrogen, alkyl of 1 to 10 carbon atoms, phenyl optionally substituted at any one position with chloride, bromide, iodide, cyano, or alkyl of 1 to 4 carbon atoms, or benzyl, optionally substituted at any one position of the benzyl group with chloride, bromide, iodide, cyano, or alkyl of 1 to 4 carbon atoms; (iii) compounds of Formula VI wherein R 61 , R 62 , R 63 , and R 64 , are the same or different and are each selected from alkyl of 1 to 10 carbon atoms or phenyl; and R 65 and R 66 are the same or different and are each selected from hydrogen or alkyl of 1 to 10 carbon atoms, provided that both R 65 and R 66 are hydrogen or both are alkyl, and if R 65 and R 66 are both hydrogen, not more than one of R 61 and R 62 is hydrogen and not more then one of R 63 and R 64 is hydrogen; (iv) compounds of Formula VII wherein R 71 is oxygen or sulfur, R 75 is hydrogen or dialkylamino, wherein the alkyl groups are the same or different and are each selected from alkyl of 1 to 6 carbon atoms, and R 72 , R 73 and R 71 are the same or different and are each selected from hydrogen, alkyl of 1 to 6 carbon atoms, phenyl, optionally substituted at any one position with an alkyl group of 1 to 6 carbon atoms, and benzyl, optionally substituted at any one position of the phenyl group with an alkyl group of 1 to 6 carbon atoms; and (V) the compound of Formula VIII

Claim 4

A solution according to Claim 2 wherein (A) the solvent is propylene carbonate; (B) the solution includes inert, current-carrying electrolyte, at a concentration of 0.01 M to 1.0 M in the solution at 25°C, selected from an alkali metal salt of Formula M + 3 1 X 3 5 , a tetraalkylammonium salt of Formula M + 3 2X -3 5, aluminum chloride, aluminum bromide and any combination of the foregoing salts, wherein M 3, is potassium, sodium or lithium, M + 3 2 is tetraalkylammonium wherein the alkyl groups are the same or different and are each selected from alkyl of 1 to 10 carbon atoms, and X 3 5 is chloride, bromide, BF - 4 , PF - 6 , AsF - 6 , ClO- 4 , or NO - 3 ; (C) the solution includes one or two different cations of cathodic compounds, each at a concentration of 0.01 M to 0.1 M in the solution at 25°C at zero-potential equilibrium, and (D) the solution includes one or two different anodic compounds, each at a concentration of 0.01 M to 0.1 M in the solution at 25°C at zero-potential equilibrium.

Claim 5

A solution according to Claim 3 that is thickened with 5% (w/w) to 25% (w/w) of acrylic sheet material from LUCITE L.

Claim 6

A solution according to Claim 3 wherein: (A) the cathodic compounds are selected from compounds of Formula X wherein R, o , is n-heptyl, phenyl or benzyl and X 01 is BF ; or ClO ; and the compound of formula (B) the anodic compounds are selected from the compounds of Formula XII wherein R 121 is methyl or phenyl; and the compounds of Formula XIII wherein R 132 is oxygen, sulfur or NR 133 , wherein R 133 is methyl or phenyl, and R 131 is (i) methyl or ethyl, if R 132 is oxygen or sulfur, (ii) methyl, if R 132 is N(CH 3 ), or (iii) phenyl, if R 132 is N(C 6 H 5 ); and the compound of Formula VIII and (C) the inert, current-carrying electrolyte is a compound of Formula M 2(BF ), wherein M + 4 2 is tetra-n-alkylammonium, wherein the n-alkyl groups are the same and are of 1 to 6 carbon atoms.

Claim 7

A solution according to Claim 5 wherein the inert current-carrying electrolyte is tetra-n-butylammonium fluoroborate at a concentration of 0.05 M to 0.5 M at 25°C, the cathodic compounds are selected from 1,1'-dibenzyl-4,4'-bipyridinium difluoroborate and tetramethylene bis[4(1-benzy(pyridine-4'-yl)-pyridinium]tetrafluoroborate, the anodic compounds are selected from 5,10-dihydro-5,10-dimethylphenazine and N,N,N',N'-tetramethyl-1,4-phenylenediamine, the total concentration of the cathodic compounds is 0.01 M to 0.05 M at 25°C, and the total concentration of the anodic compounds is 0.01 M to 0.05 M at 25°C.

Claim 8

A single-compartment, self-erasing, solution-phase electrochromic device which comprises, as the medium of reversibly variable transmittance to light, a solution as claimed in any one of claim 1 to 6.

Claim 9

A variable reflectance mirror which comprises a single-compartment, self-erasing, solution-phase electrochromic device which comprises, as the medium of reversibly variable transmittance to light reflected by the mirror, a solution which comprises (A) a solvent; (B) at least one cathodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible reduction waves, with the first of said. reductions accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; (C) at least one anodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible oxidation waves, with the first of said oxidations accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; and (D) if all cathodic and anodic compounds in their zero-potential equilibrium states in the solution are not ionic, an inert current-carrying electrolyte.

Claim 10

A variable reflectance mirror which comprises a single-compartment, self-erasing, solution-phase electrochromic device which comprises, as the medium of reversibly variable transmittance to light reflected by the mirror, a solution which comprises (A) a solvent; (B) at least one cathodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible reduction waves, with the first of said. reductions accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; (C) at least one anodic electrochromic compound which, in a voltammogram done in the solvent at room temperature, displays at least two chemically reversible oxidation waves, with the first of said oxidations accompanied by an increase in molar extinction coefficient at at least one wavelength in the visible range; and (D) if all cathodic and anodic compounds in their zero-potential equilibrium states in the solution are not ionic, an inert current-carrying electrolyte.

Claim 11

A mirror according to Claim 8 wherein, in the electrochromic device, the solution of reversibly variable transmittance is between and in contact with two planar, parallel, spaced-apart walls, at least one of which is transparent and each of which, on the side in contact with said solution, is coated with an electrode layer of electrically conductive material, provided that, if one of said walls is not transparent, it comprises a reflecting layer of high reflectance material which reflects through said solution and the transparent wall light which reaches said reflecting layer after entering the solution through the transparent wall.

Claim 12

A mirror according to Claim 9 wherein, in the solution of reversibly variable transmittance is a solution as claimed in any one of claims 2 to 6.

Claim 13

A mirror according to Claim 9 or claim 10 (A) both electrode-bearing walls of the electrochromic device are glass with an electrode layer of indium-doped tin oxide in contact with the solution of reversibly variable transmittance, the separation of the electrode layers being 0.006 cm to 0.025 cm; and (B) (i) one of said walls is transparent to light of visible wavelengths and the other of said walls is coated, on the side opposite the electrode-bearing side, with a reflecting layer; or (ii) both of said walls are transparent to light of visible wavelengths and the reflecting means of the mirror is the highly reflective surface of a prism-shaped mirror laminated through a transparent laminating material to one of said walls, the angle between the highly reflective surface and the laminated surface of the prism-shaped mirror being 1 ° to 5°; provided that, if one of the electrode-bearing walls is coated with a reflecting layer, the other of the electrode-bearing walls optionally is laminated through a transparent laminating material to a prism-shaped piece of glass wherein the angle between the surface laminated to the electrode-bearing wall and the other surface, through which passes substantially all of the light reaching the electrode-bearing wall, is 1 ° to 5°.

Claim 14

A mirror according to Claim 11 wherein the reflecting means is the highly reflective surface of a prism-shaped mirror laminated to one of the electrode-bearing walls of the electrochromic device.

Claim 15

A compound of Formula Lll wherein R 16 is oxygen or sulfur, R 80 is hydrogen or dialkylamino, wherein the alkyl groups are the same or different and are each of 1 to 6 carbon atoms, and R77, R7 9 and R 79 are the same or different and are each selected from hydrogen, alkyl of 1 to 6 carbon atoms, phenyl optionally substituted at any one position with an alkyl group of 1 to 6 carbon atoms, and benzyl, optionally substituted at any one position of the phenyl group with an alkyl group of 1 to 6 carbon atoms.

Claim 16

A compound of Formula Lll wherein R 16 is oxygen or sulfur, R 80 is hydrogen or dialkylamino, wherein the alkyl groups are the same or different and are each of 1 to 6 carbon atoms, and R77, R7 9 and R 79 are the same or different and are each selected from hydrogen, alkyl of 1 to 6 carbon atoms, phenyl optionally substituted at any one position with an alkyl group of 1 to 6 carbon atoms, and benzyl, optionally substituted at any one position of the phenyl group with an alkyl group of 1 to 6 carbon atoms.

Claim 17

A compound according to Claim 13 wherein R7 6 is oxygen, R 80 is hydrogen, and R » , R 78 and R 79 are methyl.

Claim 18

A variable reflectance mirror which comprises a device of reversibly variable transmittance, a planar front surface, and a planar reflecting means, (A) said device comprising (i) a medium of transmittance which is reversibly varied by thermochromic, photochromic, or electro-optic means, and (ii) two planar, parallel, spaced-apart surfaces, between which the medium of reversibly variable transmittance is held and through which light passes prior to and after reflecting from said reflecting means; with (B) the angle between the plane of said front surface and the plane of said reflecting means being 1 ° to 5°.

Claim 19

A variable reflectance mirror which comprises a device of reversibly variable transmittance, a planar front surface, and a planar reflecting means, (A) said device comprising (i) a medium of transmittance which is reversibly varied by thermochromic, photochromic, or electro-optic means, and (ii) two planar, parallel, spaced-apart surfaces, between which the medium of reversibly variable transmittance is held and through which light passes prior to and after reflecting from said reflecting means; with (B) the angle between the plane of said front surface and the plane of said reflecting means being 1 ° to 5°.

Claim 20

A mirror according to Claim 15 wherein (A) the reflecting means is the highly reflective surface of a prism-shaped mirror which (i) is laminated through a transparent laminating material to one of said planar, parallel, spaced-apart surfaces of the device of reversibly variable transmittance, the angle between the plane of the one of said surfaces to which the prism-shaped mirror is laminated and the highly reflective surface of the prism-shaped mirror being 1 ° to 5°, or (ii) provides the solid material layer portion of a wall of the device of reversibly variable transmittance, said wall being parallel to the planar front surface of the variable reflectance mirror; or (B) the reflecting means is a highly reflective material coated on one of said planar, parallel, spaced-apart surfaces of the device of reversibly variably transmittance and the front surface is a surface of a transparent prism-shaped object which (i) is laminated through a transparent laminating material to the planar, parallel, spaced-apart surface of the device of reversibly variable transmittance which is not coated with highly reflective material, or (ii) provides the solid material layer portion of a wall of the device of reversibly variable transmittance, said wall being parallel to the plane of the reflecting means of the variable reflectance mirror.

Claim 21

A mirror according to Claim 16 wherein the transmittance of the medium of reversibly variable transmittance is varied by liquid crystal, dipolar suspension, electrophoretic or electrochromic means.

Claim 22

The mirror according to Claim 17 wherein the device of reversibly variable transmittance is a single-compartment, setf-erasing, solution-phase electrochromic device wherein transmittance is reduced upon electrochsmical oxidation of at least one anodic electrochromic compound and simultaneous electrochemical reduction of at least one cathodic electrochromic compound and wherein self-erasing occurs, upon elimination or reduction of the potential between the electrodes of the device, by reaction of reduced cathodic electrochromic compounds with oxidized anodic electrochromic compounds.

Claim 23

The mirror according to Claim 18 wherein the reflecting means is a highly reflective material coated on the side, opposite that facing the solution, of a wall of the device of reversible variable transmittance.

Claim 24

The mirror according to Claim 19 wherein the highly reflective material of the reflecting means is a silver coating and wherein the transparent prism-shaped object is glass laminated to the device of reversibly variable transmittance.

Claim 25

The mirror according to Claim 20 wherein the reflecting means is the highly reflective surface of a prism-shaped mirror and the prism-shaped mirror is laminated to the device of reversibly variable transmittance.