Black electrochromic compound, and electrolyte-integrated radiation curable electrochromic composition and electrochromic device which contain same

Abstract

The present invention relates to an electrochromic compound, and an electrochromic composition and an electrochromic device, including the same. The electrochromic compound according to the present invention may achieve excellent black coloring effects and excellent curing characteristics, and thus may be used advantageously in an electrochromic device.

Claims

1. A compound having the following Chemical Formula 1: ##STR00024## where, R is each independently selected from the group consisting of hydrogen, a halogen, a C.sub.1-C.sub.20 alkyl, a halogenated C.sub.1-C.sub.20 alkyl, an aryl group, an alkyl group linked to oxygen and nitrogen, a C.sub.6-C.sub.40 aryl group linked to oxygen and nitrogen, and a compound of the following Chemical Formula 2, with a proviso that at least three R's represent a substituent of the following Chemical Formula 2: ##STR00025## where, X−represents a counter-anion, A is not present or is selected from the group consisting of a C.sub.1-C.sub.10 alkylene; a halogenated C.sub.1-C.sub.10 alkylene; a C.sub.2-C.sub.10 alkenylene; a halogenated C.sub.2-C.sub.10 alkenylene; a C.sub.2-C.sub.10 alkynylene; a halogenated C.sub.2-C.sub.10 alkynylene; and a heteroatom selected from N, P, O, and S, and Z is independently selected from the group consisting of a C.sub.1-C.sub.20 alkyl; a C.sub.1-C.sub.20 alkyl substituted with CN; a C.sub.1-C.sub.20 alkoxy; CN; a C.sub.2-20 alkenyl; a C.sub.2-20 alkynyl; a 3- to 10-membered ring cycloalkyl; a 3- to 10-membered ring heterocycloalkyl comprising a heteroatom selected from N, P, O, and S; a C.sub.6-40 aryl; a C.sub.6-40 aryl substituted with one or more substitution groups selected from a C.sub.1-C.sub.20 alkyl, a C.sub.1-C.sub.20 alkoxy, a C.sub.1-C.sub.20 aryloxy, a halogen, a hydroxyl, and CN; and a C.sub.6-40 heteroaryl comprising a heteroatom selected from N, P, O, and S, with the proviso that the at least one R group that is of the Chemical Formula 2 has Z independently selected from the group consisting of a C.sub.1-C.sub.20 alkyl; a C.sub.1-C.sub.20 alkyl substituted with CN; a C.sub.1-C.sub.20 alkoxy; CN; a C.sub.2-20 alkenyl; a C.sub.2-20 alkynyl; a 3- to 10-membered ring cycloalkyl; and a 3- to 10-membered ring heterocycloalkyl including a heteroatom selected from N, P, O, and S, and with the proviso that the at least one R group that is of the Chemical Formula 2 has Z independently selected from the group consisting of a C.sub.6-40 aryl; a C.sub.6-40 aryl substituted with one or more substitution groups selected from a C.sub.1-C.sub.20 alkyl, a C.sub.1-C.sub.20 alkoxy, a C.sub.1-C.sub.20 aryloxy, a halogen, a hydroxyl, and CN; and a C.sub.6-40 heteroaryl including a heteroatom selected from N, P, O, and S.

2. The compound of claim 1, wherein the three R's at the number 1, 3, 5 positions of Chemical Formula 1 are each independently the compound of Chemical Formula 2, and the remaining R's are independently hydrogen or a C.sub.1-C.sub.20 alkyl.

3. The compound of claim 1, wherein the A is a C.sub.1—C.sub.10 alkylene.

4. The compound of claim 1, wherein the three R's at the number 1, 3, 5 positions of Chemical Formula 1 are each independently the compound of Chemical Formula 2, and among the three R's, one R or two R's is or are selected wherein Z is independently selected from the group consisting of a C.sub.1-C.sub.20 alkyl; a C.sub.1-C.sub.20 alkyl substituted with CN; a C.sub.1-C.sub.20 alkoxy; CN; a C.sub.2-20 alkenyl; a C.sub.2-20 alkynyl; a 3- to 10-membered ring cycloalkyl; and a 3- to 10-membered ring heterocycloalkyl comprising a heteroatom selected from N, P, O, and S, in Chemical Formula 2, and the remaining two R's or one R are selected wherein Z is independently selected from the group consisting of a C.sub.6-40 aryl; a C.sub.6-40 aryl substituted with one or more substitution groups selected from a C.sub.1-C.sub.20 alkyl, a C.sub.1-C.sub.20 alkoxy, a C.sub.1-C.sub.20 aryloxy, a halogen, a hydroxyl, and CN; and a C.sub.6-40 heteroaryl comprising a heteroatom selected from N, P, O, and S, in Chemical Formula 2.

5. The compound of claim 4, wherein the C.sub.6-40 aryl has any one of the following structures: ##STR00026## where, R1 is each independently selected from the group consisting of hydrogen, a halogen, a C.sub.1-C.sub.10 alkyl, CN, a hydroxyl, and a C.sub.1-C.sub.10 alkoxy.

6. The compound of claim 1, wherein the compound is represented by the following chemical formula: ##STR00027## where X and Z are each independently the same as those defined in claim 1.

7. The compound of claim 1, wherein Z does not comprise an anchoring group.

8. The compound of claim 1, wherein X is selected from the group consisting of Cl.sup.−, Br.sup.−, I.sup.−, F.sup.−, C1O.sub.4.sup.−, BF.sub.4.sup.−, PF.sub.6.sup.−, and TFSi.sup.−.

9. The compound of claim 1, wherein the compound exhibits electrochromic characteristics.

10. An electrochromic composition comprising the compound according to claim 1 as a cathodic electrochromic material.

11. The electrochromic composition of claim 10, wherein the electrochromic composition comprises the compound as a first cathodic electrochromic material, and further comprises a compound represented by the following chemical formula as a second cathodic electrochromic material: ##STR00028## where, X− represents a counter-anion, R is independently selected from the group consisting of a C.sub.1-C.sub.20 alkyl, a C.sub.1-C.sub.20 alkyl substituted with a C.sub.6-C.sub.40 aryl, benzyl, a 3- to 10-membered ring heterocycloalkyl comprising a heteroatom, a C.sub.6-40 aryl, a C.sub.6-40 aryl substituted with a C.sub.1-C.sub.20 alkyl, and a C.sub.6-40 heteroaryl comprising a heteroatom selected from N, P, O, and S, and the second cathodic electrochromic material has discoloration characteristics in which Y is 0.93 to 1.04, L* is 8.35 to 9.35, a* is 41.03 to 46.17, and b* is −23.38 to −24.92 in the color coordinate.

12. The electrochromic composition of claim 11, wherein the second cathodic electrochromic material is represented by the following chemical formula: ##STR00029## where X− represents a counter anion.

13. The electrochromic composition of claim 11, wherein a molar ratio of the first cathodic electrochromic material: the second cathodic electrochromic material is 1:1 to 500:1.

14. The electrochromic composition of claim 10, wherein the electrochromic composition further comprises a counter oxidation compound selected from the group consisting of a ferrocene-based compound and an amine-based compound.

15. The electrochromic composition of claim 14, wherein the counter oxidation compound is one or more selected from the group consisting of ferrocene, ethyl ferrocene, propyl ferrocene, t-butyl ferrocene, a C.sub.1-C.sub.20 alkyl ferrocene, a halogenated ferrocene, phenoxazine, 5,10-dihydrophenazine, N,N,N′,N′-tetramethyl-p-phenylenediamine, phenothiazine, 10-methylphenothiazine, and isopropyl phenothiazine.

16. The electrochromic composition of claim 10, wherein the electrochromic composition further comprises a curing agent selected from the group consisting of an acrylic polymer, polyacrylate, polymethylmethacrylate, polyvinyl acetate, polyurethane, polystyrene, polyacetonitrile, cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, cellulose propionate, hydroxypropylmethyl cellulose, gum, hydrochloride, gellan, carrageenan, pullulan, polyethylene oxide, polypropylene oxide, polyvinyl acetate, poly(N-vinyl pyrrolidone), and polyvinylindene fluoride.

17. An electrochromic device comprising: a compound, or an electrochromic composition comprising the compound, wherein the compound is defined according to claim 1.

18. The electrochromic device of claim 17, wherein the electrochromic device comprises a first substrate provided with a first electrode and a second substrate provided with a second electrode, and the compound or the electrochromic composition is comprised in a space between the two substrates disposed spaced apart from each other.

19. A product comprising the electrochromic device of claim 17, which is selected from the group consisting of window glass for construction, smart window, mirror for a vehicle, a display, and an electronic shelf label (ESL).

20. A method of manufacturing an electrochromic device, the method comprising: preparing an electrochromic solution comprising: the compound according to claim 1; a counter oxidation compound selected from a ferrocene-based compound or an amine-based compound; and a curing agent; preparing a cell comprising a first substrate provided with a first electrode and a second substrate provided with a second electrode, wherein the two substrates are disposed spaced apart from each other; injecting the prepared electrochromic solution into a space between the first substrate and the second substrate of the cell; and curing the injected solution.

21. The method of claim 20, wherein the electrochromic solution further comprises a compound represented by the following chemical formula as a second cathodic electrochromic material: ##STR00030## where, X− represents a counter-anion, R is independently selected from the group consisting of a C.sub.1-C.sub.20 alkyl, a C.sub.1-C.sub.20 alkyl substituted with a C.sub.6-C.sub.40 aryl, benzyl, a 3- to 10-membered ring heterocycloalkyl comprising a heteroatom, a C.sub.6-40 aryl, a C.sub.6-40 aryl substituted with a C.sub.1-C.sub.20 alkyl; and a C.sub.6-40 heteroaryl comprising a heteroatom selected from N, P, O, and S, and the second cathodic electrochromic material has discoloration characteristics in which Y is 0.93 to 1.04, L* is 8.35 to 9.35, a* is 41.03 to 46.17, and b* is −23.38 to −24.92 in the color coordinate.

Description

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS

(1) Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It will also be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

(2) Description will now be given in detail of a drain device and a refrigerator having the same according to an embodiment, with reference to the accompanying drawings.

(3) Hereinafter, the present invention will be described in more detail through the Examples. These Examples are provided only for more specifically describing the present invention, and it will be obvious to a person with ordinary skill in the art to which the present invention pertains that the scope of the present invention is not limited by these Examples.

EXAMPLES

I. Preparation Example

1. Synthesis of First Cathodic Electrochromic Material (Containing Viologen)

(4) A first cathodic electrochromic material containing viologen may be prepared through the steps such as the following reaction formulae.

(5) ##STR00009## ##STR00010##

(1) Synthesis of Compound of Chemical Formula 1A

(6) ##STR00011##

(7) 12.7 g of 4,4′-bipyridyl and 10.0 g of 4-bromobutyronitrile were refluxed in 50 ml of acetonitrile for a day. A precipitate was left behind by filtering the mixture, and the filtered liquid was refluxed again. A yellow solid, which is a precipitate, was stirred in 200 ml of acetone and filtered. The reflux and filtration process was repeated three times. The yellow precipitate was all collected, washed with acetone, and dried at normal temperature under reduced pressure. A compound of Chemical Formula 1A at a yield of 64% was obtained.

(8) ##STR00012##

(2) Synthesis of Compound of Chemical Formula 1B

(9) ##STR00013##

(10) 9.2 g of 4,4′-bipyridyl and 10.0 g of 1-chloro-2,4-dinitrobenzene were refluxed in 50 ml of acetonitrile for 3 days. Subsequently, a yellow residue was filtered, and the filtrate was refluxed again. An obtained yellow solid was stirred in 500 ml of acetone and filtered. The reflux process was repeated three times. Precipitates obtained through the repeated reflux and filtration were washed several times with acetone. Subsequently, a compound of Chemical Formula 1A was obtained by drying the precipitate at a temperature of 100° C. in an oven, and the yield thereof was 70%.

(11) ##STR00014##

(3) Synthesis of Compound of Chemical Formula 1C

(12) ##STR00015##

(13) 20.0 g of the compound of Chemical Formula 1B and 17.8 g of para-toluidine were refluxed in 500 ml of ethyl alcohol for 3 days. A precipitate was filtered, and a filtered solution was refluxed again. A yellow precipitate was stirred in 500 ml of acetone and filtered, and the reflux process was repeated twice. The filtered precipitate was washed several times with acetone. Subsequently, a compound of Chemical Formula 1C was obtained by drying the precipitate at a temperature of 100° C. in an oven, and the yield thereof was 89%.

(14) ##STR00016##

(4) Synthesis of Compound of Chemical Formula 1D

(15) ##STR00017##

(16) 3.0 g of 1,3,5-trisbromomethylbenzene, 10.8 g of the compound of Chemical Formula 1A, and 5 g of the compound of Chemical Formula 1C were refluxed in 300 ml of methanol for 5 days. Subsequently, a dark brown solid obtained after removing the solvent was dried. The compound obtained above and 42 g of bis(trifluoromethane)sulfonimide lithium salt were dissolved in 400 ml of distilled water and mixed. Subsequently, a solid obtained by filtering the reactant liquid was dissolved in acetonitrile and dried by using MgSO.sub.4. A compound of Chemical Formula 1D was obtained by vacuum-drying a solid obtained through concentration under reduced pressure, and the yield thereof was 70%.

(17) ##STR00018##

2. Synthesis of Second Cathodic Electrochromic Material (Toning Agent)

(18) A second cathodic electrochromic material containing viologen may be prepared through the steps such as the following reaction formulae.

(19) ##STR00019##

(1) Synthesis of Compound of Chemical Formula 2A

(20) ##STR00020##

(21) 10.0 g of 4,4′-bipyridyl and 9.9 g of benzyl bromide were stirred in 150 ml of acetone at 50° C. for 3 days, subsequently, a yellow precipitate was filtered, and the filtered solution was stirred again. The stirring and filtration process was repeated three times. A yellow precipitate obtained after the filtration was stirred in 500 ml of acetone and filtered. Subsequently, the precipitate was filtered and washed several times with acetone. Subsequently, a compound of Chemical Formula 2A was obtained by drying the precipitate at a temperature of 70° C. in an oven, and the yield thereof was 75%.

(22) ##STR00021##

(2) Synthesis of Compound of Chemical Formula 2B

(23) ##STR00022##

(24) 5.0 g of 1,2-bisbromomethyl benzene and 27 g of the compound of Chemical Formula 2A were refluxed in 100 ml of methanol for 3 days. Subsequently, a pale yellow solid obtained after removing the solvent was dried. The compound obtained above and 37 g of bis(trifluoromethane)sulfonimide lithium salt were dissolved in 400 ml of distilled water, and then mixed. Subsequently, a solid obtained by filtering the reactant liquid was dissolved in acetonitrile and the solution was dried by using MgSO.sub.4. A compound of Chemical Formula 2B was obtained by vacuum-drying a solid obtained through concentration under reduced pressure, and the yield thereof was 68%.

(25) ##STR00023##

3. Preparation of Black Electrochromic Composition

(26) A Solution:

(27) Viologen and ferrocene of the prepared first cathodic electrochromic material (Chemical Formula 1D) were dissolved at a concentration of 49 mM and 146 mM, respectively in propylene carbonate (PC). 7 g of the corresponding solution and 3 g of a photocurable gel electrolyte (LiTFSi 1.4 M, curing composition 40 wt %) were mixed and appropriately stirred. B Solution:

(28) Viologen and ferrocene of the prepared second cathodic electrochromic material (Chemical Formula 2B) were dissolved at a concentration of 73 mM and 146 mM, respectively in PC. 7 g of the corresponding solution and 3 g of a photocurable gel electrolyte (LiTFSi 1.4 M, curing composition 40 wt %) were mixed and appropriately stirred.

4. Manufacture of Device

(29) A cell was manufactured by joining two sheets of ITO glass with a size of 50×50 mm, such that the ITO surfaces face each other so as to maintain a space gap of 240 μm. After the A Solution and a mixed solution of A+B (A/B=88/12) were injected into the cell, the injection port was clogged, and the solutions were cured by exposing the cell at 2,000 mJ/m.sup.2.

II. Experimental Example

1. Electrochromic Characteristics

(1) Example

(30) The black specifications to be currently developed in the field to which the present invention pertains are Y: 1% or less, L*<32+3, a*: −4±1, and b*: 1±1, and in the present experimental example, the degree of electrochromism was measured by using the manufactured cell. Specifically, after a 1.5 V DC voltage was applied to the cell by using a DC power supply, the transmittance was measured by using a spectrometer in order to confirm the degree of electrochromism, and the results thereof are shown in the following Table 1.

(31) TABLE-US-00001 TABLE 1 Y L* a* b* A 1.27 11.09 −13.83 7.47 A/B = 88/12 0.78 7.00 −4.20 0.46

(32) As a result of the experiment, it was confirmed that even when only the first cathodic electrochromic material was included, the black coordinate was satisfied, and it was confirmed that when the second cathodic electrochromic material was mixed with the first cathodic electrochromic material, all the black specifications required in the same field were satisfied, and an excellent black color was implemented.

(2) Comparative Example: Comparison with RGB Combination

(33) C Solution: Violgen taking on the blue color and ferrocene were dissolved at a concentration of 146 mM and 146 mM, respectively in PC. 7 g of the corresponding solution and 3 g of a photocurable gel electrolyte (LiTFSi 1.4 M, curing composition 40 wt %) were mixed and appropriately stirred. D Solution: Violgen taking on the green color and ferrocene were dissolved at a concentration of 146 mM and 146 mM, respectively in PC. 7 g of the corresponding solution and 3 g of a photocurable gel electrolyte (LiTFSi 1.4 M, curing composition 40 wt %) were mixed and appropriately stirred.

(34) Cells were manufactured by mixing red, blue, and green (B/C/D) at various toning ratios, the transmittance was measured by the same method as described above, and the results thereof are shown in the following Table 2.

(35) TABLE-US-00002 TABLE 2 Y L* a* B RGB 1/5/4 1.02 6.97 13.89 −22.07 RGB 1/6/3 0.99 6.70 9.54 −17.42 RGB 1/7/2 0.96 6.44 5.20 −12.76 RGB 1/8/1 0.93 6.17 0.85 −8.11

(36) Through the Example and the Comparative Example, it was confirmed that the case where a*: −4±1 and b*: 1±1, which are the black specification conditions required in the same field, were satisfied could be achieved only when the first cathodic electrochromic material was essentially contained.

2. Gelation Characteristics

(37) As a result of observing the curing uniformity of the electrochromic devices suggested in the Example and the Comparative Example, it was confirmed that no cured foreign substances such as bubbles and localized cured material aggregation that could be generated during the curing process were not generated at all, and the test device was also driven very uniformly.

(38) Further, as a result of dismantling the device in order to confirm the state of the curing composition liquid in the test device, it was confirmed that a highly viscous gel having no flowing characteristics of the solution was prepared.

3. Repeated Driving Test

(39) In order to confirm the difference in performance between Chemical Formula 1D and an electrochromic material of Chemical Formula 1 including an anchoring group, a cell was manufactured by joining two sheets of ITO glass with a size of 50×50 mm with the same solution composition, such that the ITO surfaces face each other so as to maintain a space gap of 90 μm. In this case, the used solution composition was violgen and ferrocene at 58 mM and 23 mM, respectively, and the remaining compositions are the same as those in the above-described Example.

(40) Gelation characteristics, driving uniformity, and the like of the manufactured test device were excellent, regardless of whether the anchoring group was present or not.

(41) Meanwhile, the results of repeating discoloration and decolorization 100 times by allowing each test device to be on and off at a voltage of 1.0 V for 20 seconds and 20 seconds, respectively were shown in the following Table 3.

(42) TABLE-US-00003 TABLE 3 Sample Driving Cycle Y(D65) L*(D66) a*(D65) B*(D65) Containing  0 time 86.11 94.36 −2.08 1.77 no Anchor  1 time 16.82 48.03 −16.19 −11.33 100 times 16.25 47.51 −16.46 −10.87 Containing  0 time 86.95 94.72 −2.68 3.31 Anchor  1 time 17.61 49.02 −22.27 −1.55 100 times 81.39 92.30 −5.07 3.98

(43) As confirmed in Table 3, it was confirmed that when the anchoring group is included, deterioration in performance caused by repeated driving was severe. As a cause for the severe deterioration, it is determined that in a solution-phase electrochromic device in which the anchoring group adopts the diffusion of the electrochromic material as a main mechanism, deterioration in electrode characteristics, reduction in diffusion rate, and the like are caused by strong hydrogen bond characteristics of the anchoring group.