阅读说明：本技术 用于形成溶液型电致变色层的组合物以及由其制备的电致变色层和电致变色装置 (Composition for forming solution-type electrochromic layer, and electrochromic layer and electrochromic device prepared therefrom ) 是由 林昇辉 于 2019-09-24 设计创作，主要内容包括：本申请涉及用于形成溶液型电致变色层的组合物以及由其制备的电致变色层和电致变色装置,其中,所述用于形成溶液型电致变色层的组合物包含：多异氰酸酯；至少一种高分子量多元醇,其数均分子量Mn在1500到10000范围内,优选1500到5000范围内；至少一种低分子量多元醇,其数均分子量Mn小于1500,优选在300到1000范围内,更优选在500到1000范围内；阳极电致变色化合物；阴极电致变色化合物和溶剂。所述电致变色装置包括设置有透明导电层的第一透明基板、设置有导电反射层的第二基板和位于所述第一透明基板和所述第二基板之间的本发明的组合物形成的溶液型电致变色层。(The present application relates to a composition for forming a solution-type electrochromic layer, and an electrochromic layer and an electrochromic device prepared therefrom, wherein the composition for forming a solution-type electrochromic layer comprises: a polyisocyanate; at least one high molecular weight polyol having a number average molecular weight Mn in the range of 1500 to 10000, preferably 1500 to 5000; at least one low molecular weight polyol having a number average molecular weight Mn of less than 1500, preferably in the range of 300 to 1000, more preferably in the range of 500 to 1000; an anodic electrochromic compound; a cathodic electrochromic compound and a solvent. The electrochromic device includes a first transparent substrate provided with a transparent conductive layer, a second substrate provided with a conductive reflective layer, and a solution-type electrochromic layer formed of the composition of the present invention between the first transparent substrate and the second substrate.)

1. A composition for forming a solution-type electrochromic layer, comprising:

-a polyisocyanate, which is,

at least one high molecular weight polyol having a number average molecular weight Mn in the range from 1500 to 10000, preferably from 1500 to 5000,

at least one low molecular weight polyol having a number average molecular weight Mn of less than 1500, preferably in the range from 300 to 1000, more preferably in the range from 500 to 1000,

-an anodic electrochromic compound,

a cathodic electrochromic compound, and

-a solvent.

2. The composition of claim 1, further comprising one or more additives selected from the group consisting of: light absorbers, reducing compounds, light stabilizers, heat stabilizers, antioxidants, oxygen scavengers, viscosity modifiers, toners, redox buffers, and curing catalysts.

3. The composition of claim 1 or 2, wherein the polyisocyanate has an NCO functionality of 2 or greater, the at least one high molecular weight polyol and the at least one low molecular weight polyol each have an OH functionality of 2 or greater, and the NCO functionality of the polyisocyanate and the OH functionality of both polyols are not both 2; preferably, the polyisocyanate has an NCO functionality of 3 and the OH functionalities of the two polyols are 2.

4. The composition of any of claims 1-3, wherein the high molecular weight polyol and/or the low molecular weight polyol is selected from polycarbonate polyols, polyester polyols, polycaprolactone polyols, polyether polyols, or any mixtures thereof.

5. The composition of claim 4, wherein the polycarbonate polyol has the general formula:

wherein R independently represents a substituted or unsubstituted aliphatic divalent hydrocarbon group, a substituted or unsubstituted aromatic divalent hydrocarbon group, a substituted or unsubstituted alicyclic divalent hydrocarbon group, a substituted or unsubstituted aliphatic aromatic mixed divalent hydrocarbon group;

preferably, R independently represents C2-C10 aliphatic divalent hydrocarbon group, substituted or unsubstituted C6-C10 aromatic divalent hydrocarbon group, substituted or unsubstituted C3-C10 alicyclic divalent hydrocarbon group, substituted or unsubstituted C7-C10 aliphatic aromatic mixed divalent hydrocarbon group;

more preferably, R represents, independently of one another, propylene, butylene, pentylene, hexylene, heptylene, octylene and isomers thereof,

n＝4～100。

6. the composition of claim 4, wherein the mass ratio of the at least one high molecular weight polyol to the at least one low molecular weight polyol is in the range of 2:1 to 15:1, preferably in the range of 5:1 to 12:1, more preferably in the range of 8:1 to 10: 1.

7. The composition of any of claims 1-6, wherein the anodic electrochromic compound is selected from one or more compounds of the group consisting of: metallocenes, phenazines, phenothiazines, phenoxazines, carbazoles, triphendithiazines, triphendioxazines and derivatives thereof, preferably the anodic electrochromic compound is one or more compounds selected from the group consisting of: di-tert-butyl-diethylferrocene, 5, 10-dihydro-5, 10-dimethylphenazine, 3,7, 10-trimethylphenothiazine, 2,3,7, 8-tetramethoxy-thianthrene, 10-methylphenothiazine, tetramethylphenazine, bis (butyltriethylammonium) -p-methoxytriphenodithiazine and 3, 10-dimethoxy-7, 14- (triethylammoniumbutyl) -triphenodithiazine bis (tetrafluoroborate).

8. The composition of any of claims 1-7, wherein the cathodic electrochromic compound is a viologen-based electrochromic compound, preferably 1,1 '-dimethyl-4, 4' -bipyridine bis (tetrafluoroborate).

9. The composition of any one of claims 1 to 8, wherein, based on the total weight of the composition,

-the amount of said polyisocyanate is from 0.5 to 15% by weight, preferably from 0.8 to 10% by weight, more preferably from 0.8 to 7% by weight;

-the total amount of the at least one high molecular weight polyol and the at least one low molecular weight polyol is from 0.5 to 15 wt.%, preferably from 2 to 12 wt.%, more preferably from 3 to 10 wt.%;

-the amount of said anodic electrochromic compound is between 0.1 and 10% by weight, preferably between 0.2 and 7% by weight, more preferably between 0.3 and 5% by weight;

-the amount of the cathodic electrochromic compound is from 0.1 to 10% by weight, preferably from 0.2 to 7% by weight, more preferably from 0.3 to 5% by weight;

the amount of solvent is from 60 to 95% by weight, preferably from 80 to 95% by weight.

10. The composition of any of claims 1-9, wherein the molar ratio of NCO groups of the polyisocyanate to OH groups of all polyols is from 1:1 to 1:2, more preferably from 1:1 to 1:1.5, more preferably from 1:1 to 1: 1.3.

11. A solution-type electrochromic layer formed by curing the composition of any one of claims 1 to 10.

12. An electrochromic device comprising

-a first transparent substrate provided with a transparent conductive layer; preferably, the transparent conductive layer comprises an indium tin oxide film layer, a zinc oxide film layer, a fluorine-doped indium tin oxide film layer, a fluorine-doped tin oxide film layer or a fluorine-doped zinc oxide film layer; preferably, the first transparent substrate is inorganic glass or organic glass;

-a second substrate provided with a conductive reflective layer; preferably, the conductive reflective layer comprises a chromium-plated film layer, a silver-plated film layer, a palladium-plated film layer, a ruthenium-plated film layer, a rhodium-plated film layer, a platinum-plated film layer or a gold-plated film layer; and

-a solution-type electrochromic layer formed from the composition of claim 1, located between the first transparent substrate and the second substrate.

13. The electrochromic device of claim 12, further comprising a sealing member, preferably formed from a sealant, the sealing member forming a chamber with the first and second transparent substrates that holds the solution-based electrochromic layer.

14. The electrochromic device of claim 13, wherein glass frit is included as a support in the sealing member.

Technical Field

The present invention relates to the field of electrochromism, and in particular, to a composition for forming a solution-type electrochromic layer, and an electrochromic layer and an electrochromic device prepared therefrom.

Background

Electrochromism is a phenomenon in which when an electric field is applied or current is applied to a color-changeable material, the optical properties (for example, transmittance, reflectance, or absorption of light) of the material change reversibly and stably in a certain wavelength range of visible light. Typically, electrochromism manifests as a reversible change in color and/or transparency.

Electrochromic devices are currently applied to various fields, for example, automotive glass (including windows, skylights, etc.), architectural glass, display devices, optical elements, mirrors, electromagnetic wave shields, and the like, and particularly, automotive rearview mirrors for reducing glare, smart windows for adjusting reflection or absorption of sunlight according to changes in light. When the anti-glare automobile rearview mirror is used as an anti-glare automobile rearview mirror, the anti-glare automobile rearview mirror can be darkened by applying a potential, so that glare caused by other automobile lamp light rays is prevented.

Solution-type electrochromic devices are known, which are described, for example, in US4,902,108. In a typical solution type electrochromic device, two substrates and a sealant form a thin cavity for containing a solution containing an electrochromic material. However, such devices tend to segregate in solution as anodic and reduced forms of cathodic electrochromic materials are continuously operated for extended periods of time. By thickening or gelling the solution, segregation due to natural convection of the electrochromic medium can be reduced, thereby reducing its undesirable effects, such as uneven coloration or transparency.

The thickened or gelled solutions of the prior art have a number of disadvantages in electrochromic devices, for example, especially in the case of large windows or rear-view mirrors, where the devices are usually placed vertically, the hydrostatic pressure making the solution-type electrochromic devices prone to breakage. Even without cracking, hydrostatic pressure makes the substrate of the electrochromic device prone to bending outward, which results in uneven thickness of the solution layer and uneven coloring and uneven transparency of the electrochromic device when in operation. The self-supporting matrix can be established by thickening the solution using a cross-linked polymer matrix formed by the reaction, such that the solution is entrained in the network of cross-linked polymer without imparting undesirable hydrostatic pressure to the substrate of the electrochromic device.

However, the crosslinked polymer matrix formed by the reaction in the prior art also has problems such as insufficient high temperature/high pressure resistance, inability to withstand severe temperature differences, i.e., poor weather resistance and poor temperature impact resistance; chemical intolerance, etc.

Disclosure of Invention

The present inventors have found that the above technical problems can be solved by selecting monomer components for forming a cross-linked polymer matrix, and thus, the present invention provides a composition for forming a solution-type electrochromic layer, and an electrochromic layer and an electrochromic device formed therefrom. The electrochromic device of the present invention has excellent high temperature/high pressure resistance (weather resistance and temperature impact resistance).

In one aspect of the present invention, there is provided a composition for forming a solution-type electrochromic layer, the composition comprising:

polyisocyanates, and mixtures thereof

At least one high molecular weight polyol having a number average molecular weight Mn in the range from 1500 to 10000, preferably from 1500 to 5000,

at least one low molecular weight polyol having a number average molecular weight Mn of less than 1500, preferably in the range from 300 to 1000, more preferably in the range from 500 to 1000,

-an anodic electrochromic compound,

a cathodic electrochromic compound, and

-a solvent.

In another aspect of the present invention, there is provided a solution-type electrochromic layer formed by curing the composition of the present invention.

In yet another aspect of the present invention, there is provided an electrochromic device including

-a first transparent substrate provided with a transparent conductive layer; preferably, the transparent conductive layer comprises an indium tin oxide film layer, a zinc oxide film layer, a fluorine-doped indium tin oxide film layer, a fluorine-doped tin oxide film layer or a fluorine-doped zinc oxide film layer; preferably, the first transparent substrate is inorganic glass or organic glass;

-a second substrate provided with a conductive reflective layer; preferably, the conductive reflective layer comprises a chromium-plated film layer, a silver-plated film layer, a palladium-plated film layer, a ruthenium-plated film layer, a rhodium-plated film layer, a platinum-plated film layer or a gold-plated film layer; and

-a solution-type electrochromic layer formed from the composition of the invention, located between the first transparent substrate and the second substrate.

Drawings

Fig. 1 is a front view of an electrochromic device of the present invention.

Fig. 2 is a cross-sectional view taken along a-a in fig. 1.

Wherein the reference numerals

1 is a first substrate

2 is a transparent conductive layer

3 is a sealing member

4 is a cavity

5 is a conductive reflective layer

6 is a second substrate

7 is a perfusion hole

Detailed Description

All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety, to the same extent as if each was specifically and individually indicated to be incorporated by reference in its entirety.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

All percentages, parts, ratios, etc., are by weight unless otherwise indicated.

When an amount, concentration, or other value or parameter is expressed in terms of a range, preferred range, or upper preferable numerical value and lower preferable numerical value, it is understood that any range defined by any pair of upper range limits or preferred numerical values in combination with any lower range limits or preferred numerical values is specifically disclosed, regardless of whether the range is specifically disclosed. Unless otherwise indicated, numerical ranges set forth herein are intended to include the endpoints of the ranges, and all integers and fractions within the ranges.

Herein, the term "formed of … …" or "consisting of … …" is equivalent to "comprising/including". As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," "contains" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus. Also, unless expressly stated to the contrary, "or" means including "or" and not an exclusive "or". For example, any of the following conditions satisfies condition a or B: a is true (or present) and B is false (or not present), a is false (or not present) and B is true (or present), and both a and B are true (or present).

In addition, the word "a" or "an" preceding a certain element or component of the invention is not limiting as to the number of such elements or components. Thus, "a" or "an" should be understood to include one or at least one and the singular forms of a stated element or component also include the plural unless the singular is explicitly stated.

The materials, methods, and examples of the present invention are illustrative only and not intended to be limiting unless otherwise specified. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below.

When the term "about" is used to describe a value or an endpoint of a range, it should be understood to include within ± 10%, ± 5%, ± 3% or ± 1% of the specific value or endpoint involved. In the present invention, each specific numerical value referred to should be considered modified by "about".

The composition for forming a solution-type electrochromic layer according to the present invention, and the electrochromic layer and electrochromic device formed therefrom will be described in detail below.

Composition for forming solution-type electrochromic layer

The composition for forming a solution-type electrochromic layer of the present invention comprises:

polyisocyanates, and mixtures thereof

At least one high molecular weight polyol having a number average molecular weight Mn in the range from 1500 to 10000, preferably from 1500 to 5000,

at least one low molecular weight polyol having a number average molecular weight Mn of less than 1500, preferably in the range from 300 to 1000, more preferably in the range from 500 to 1000,

-an anodic electrochromic compound,

a cathodic electrochromic compound, and

-a solvent.

In the present invention, the solution type electrochromic layer means a layer containing an electrochromic solution or a dielectric layer sandwiched between two substrates.

In the present invention, the "polyisocyanate" has 2 or more, for example 3, 4, 5 or 6, isocyanate groups. In the present invention, the NCO functionality means the number of NCO groups per polyisocyanate molecule, for example, having 2 or more isocyanate groups is also referred to as NCO functionality of 2 or more. In the present invention, the polyisocyanate is also referred to as NCO component, which may be a single ingredient or a mixture.

In the present invention, the "polyol" refers to an organic or inorganic alcohol with 2 or more, e.g. 3, 4, 5 or 6, OH groups. In the present invention, the OH functionality refers to the number of OH groups per polyol molecule, for example, having 2 or more OH is also referred to as OH functionality of 2 or more. In the present invention, at least one high molecular weight polyol and at least one low molecular weight polyol are collectively referred to as the OH component.

In the present invention, the NCO component should be capable of forming a crosslinked polymer with the OH component, and the "crosslinked polymer" refers to a polymer having a three-dimensional network structure. The other components of the composition are interspersed within the crosslinked polymer. In the present invention, the term "dispersed in the crosslinked polymer" means that the other components of the composition are dispersed in the network voids of the crosslinked polymer, that is, the network voids of the crosslinked polymer are filled, and the other components do not serve as the constituent components of the crosslinked polymer.

In order to form a crosslinked polymer, the NCO functionality of the NCO component and the OH functionality of the OH component are not both 2. That is, when the NCO component used has an NCO functionality of 2, the OH functionality of the OH component is greater than 2; when the OH component used has an OH functionality of 2, the NCO component has an NCO functionality of more than 2. The NCO functionality referred to herein is the average functionality of the NCO component and the OH functionality referred to herein is the average functionality of the OH component. Thus, where the NCO component and/or OH component used is a mixture, it is contemplated that there can be instances where both the NCO functionality of a certain NCO component and the OH functionality of a certain OH component are 2.

Preferably, in the composition of the present invention, the NCO component has an NCO functionality of 3 and the OH component has an OH functionality of 2.

In the present invention, the OH groups are present in molar excess relative to the NCO groups. In particular, the preferred molar ratio of NCO groups to OH groups is from 1:1 to 1:2, more preferably from 1:1 to 1:1.5, more preferably from 1:1 to 1:1.3, most preferably 9: 10.

Polyisocyanates that may be used in the present invention include, but are not limited to, monomeric isocyanates containing two or three NCO groups and dimers or trimers thereof. For example, they include the well-known aliphatic, cycloaliphatic or aromatic monomeric diisocyanates and dimers or trimers thereof. Specific examples include: aromatic polyisocyanates, for example isomers of diphenylmethane diisocyanate (MDI), such as 4,4 '-diphenylmethane diisocyanate (4,4' -MDI), 2 '-diphenylmethane diisocyanate (2,2' -MDI), 2,4 '-diphenylmethane diisocyanate (2,4' -MDI); isomers of phenylene diisocyanate, such as 1, 3-phenylene diisocyanate, 1, 4-phenylene diisocyanate; naphthylene-1, 5-diisocyanate (NDI), isomers of Toluene Diisocyanate (TDI), such as 2,4-TDI and 2, 6-TDI; m-and p-tetramethylxylylene diisocyanate (TMXDI), m-and p-Xylylene Diisocyanate (XDI), 3' -dimethyldiphenyl-4, 4' -diisocyanate (TODI), toluene diisocyanate, naphthalene, di-and tetraalkyldiphenylmethane diisocyanate, 4' -dibenzyl diisocyanate, and dimers or trimers of each of the foregoing monomers, and any combination thereof.

Aliphatic and cycloaliphatic isocyanates such as ethylene diisocyanate, dodecane diisocyanate, dimer fatty acid diisocyanate, 4 '-dibenzyl diisocyanate, 1, 6-diisocyanato-2, 2, 4-trimethylhexane, butane-1, 4-diisocyanate, hexane-1, 6-diisocyanate (HDI), tetramethoxybutane-1, 4-diisocyanate, 1, 12-diisocyanato-dodecane, 4' -dicyclohexylmethane diisocyanate, 1, 3-cyclohexane or 1, 4-cyclohexane diisocyanate, 1-methyl-2, 4-diisocyanato-cyclohexane, 1-isocyanatomethyl-3-isocyanato-1, 5, 5-trimethylcyclohexane (isophorone diisocyanate, IPDI), hydrogenated or partially hydrogenated MDI ([ H ]12MDI (hydrogenated) or [ H ]6MDI (partially hydrogenated), and dimers or trimers of the above monomers, respectively, and any combination thereof.

For example, the following commercially available products can be used as the polyisocyanate of the present invention: DESMODUR N3300 (available from Bayer MaterialScience, which is an HDI trimer with an NCO functionality of 3).

In the present invention, it is important to use a high molecular weight polyol and a low molecular weight polyol in combination as the OH component. In the present invention, the number average molecular weight Mn of the high molecular weight polyol is in the range of 1500 to 10000, preferably 1500 to 5000, more preferably 1500 to 3000; the low molecular weight polyols have a number average molecular weight Mn of less than 1500, preferably in the range of 300 to 1000, more preferably in the range of 500 to 1000.

In the present invention, the mass ratio of the at least one high molecular weight polyol to the at least one low molecular weight polyol is in the range of 2:1 to 15:1, preferably in the range of 5:1 to 12:1, more preferably in the range of 8:1 to 10:1, such as 9: 1.

In the present invention, usable high molecular weight polyol species and usable low molecular weight polyol species may be polyol species conventionally used in the art for preparing polyurethanes, for example, polycarbonate polyols, polyester polyols, polycaprolactone polyols, polyether polyols, or any mixtures thereof.

Polycarbonate polyols which can be used in the present invention have, for example, the following general formula:

wherein R represents a substituted or unsubstituted aliphatic divalent hydrocarbon group, a substituted or unsubstituted aromatic divalent hydrocarbon group, a substituted or unsubstituted alicyclic divalent hydrocarbon group, or a substituted or unsubstituted aliphatic aromatic mixed divalent hydrocarbon group, independently of each other.

Preferably, R independently of each other represents a C2-C10 aliphatic divalent hydrocarbon group, a substituted or unsubstituted C6-C10 aromatic divalent hydrocarbon group, a substituted or unsubstituted C3-C10 alicyclic divalent hydrocarbon group, or a substituted or unsubstituted C7-C10 aliphatic aromatic mixed divalent hydrocarbon group.

More preferably, R represents independently of each other a C2-C10 aliphatic divalent hydrocarbon group.

More preferably, R represents, independently of one another, propylene, butylene, pentylene, hexylene, heptylene, octylene and isomers thereof.

As substituents for the above R divalent hydrocarbon radicals, it is possible to carry OH groups, for example hydroxyalkyl radicals, where the alkyl radicals have from 1 to 10 carbon atoms, preferably from 1 to 5 carbon atoms.

n＝4～100。

Preferably, the polycarbonate polyol is an aliphatic polycarbonate polyol, preferably a C2-C10 aliphatic polycarbonate polyol.

As high molecular weight polyols, commercially available exemplary products of polycarbonate polyols that can be used in the present invention include, but are not limited to, DURANOL T5652 (which is a poly C5/C6 alkylene carbonate polyol having a number average molecular weight Mn of about 2000 and a functionality of 2) from Asahi Kasei corporation.

As a low molecular weight polyol, commercially available exemplary products that can be used for the polycarbonate polyol of the present invention include, but are not limited to, DURANOL T4671 (which is a polyalkylene carbonate polyol having a number average molecular weight Mn of about 1000 and a functionality of 2) from Asahi Kasei corporation.

Polyester polyols which can be used according to the invention are, for example, those which can be prepared by polycondensation of polycarboxylic acids with low proportions of polyols. The polycarboxylic acids may be aliphatic, cycloaliphatic, aromatic or heterocyclic di-or triacids or mixtures thereof. Examples of suitable polycarboxylic acids are aliphatic acids, such as adipic acid, sebacic acid, glutaric acid, azelaic acid, suberic acid, undecanedioic acid, dodecanedioic acid, 3-dimethylglutaric acid, hexahydrophthalic acid; aromatic acids such as phthalic acid, terephthalic acid, isophthalic acid; unsaturated acids such as maleic acid, fumaric acid, dimer fatty acids; tricarboxylic acids, such as citric acid and trimellitic acid. The low-weight polyol may be a diol or triol, for example ethylene glycol, diethylene glycol, neopentyl glycol, hexanediol, butanediol, propylene glycol, glycerol or trimethylolpropane, dipropylene glycol, 1, 4-butanediol, 1, 6-hexanediol, 1, 8-octanediol, 1, 10-decanediol, 1, 12-dodecanediol, dimer fatty alcohol, 1, 4-hydroxymethylcyclohexane, 2-methylpropane-1, 3-diol, butane-1, 2, 4-triol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycol.

Exemplary commercially available high molecular weight polyester polyols that can be used in the present invention include, but are not limited to, DESMOPHEN 1700 (which is a polyester polyol made from adipic acid and diethylene glycol, with a number average molecular weight Mn of about 2500, and a functionality of 2, available from Bayer MaterialScience).

Another suitable class of polyester polyols are based on epsilon-caprolactone, also known as polycaprolactone polyols, including polycaprolactone diols, polycaprolactone triols, polycaprolactone tetraols, and the like. For example, the polycaprolactone diol, the polycaprolactone triol and the polycaprolactone tetraol are prepared by taking ethylene glycol, trimethylolpropane and pentaerythritol as initiators and carrying out ring-opening polymerization on epsilon-caprolactone.

As a high molecular weight polyol, an exemplary commercially available polycaprolactone polyol product useful in the present invention includes DAICEL PCL220 (number average molecular weight Mn of about 2000, functionality of 2).

Other suitable polyol components are polyether polyols which are the reaction product of a low molecular weight polyol and an alkylene oxide, for example the reaction product of ethylene glycol, propylene glycol, the isomeric butanediols, hexanediol or 4,4' -dihydroxydiphenylpropane with ethylene oxide, propylene oxide or butylene oxide or a mixture of two or more thereof; or for example the reaction product of glycerol, trimethylolethane or trimethylolpropane, pentaerythritol or a sugar alcohol or two or more thereof with an alkylene oxide. Another class of polyether polyols are those which can be prepared by ring-opening polymerization of alkylene oxides, such as tetrahydrofuran, for example polytetramethylene glycol.

The polyetherester polyol useful in the present invention is a polyol comprising both polyether units and polyester units in the main chain, wherein the polyether units may be the polyether units in the aforementioned polyether polyol, and the polyester units may be the polyester units in the aforementioned polyester polyol.

In the present invention, the number average molecular weight Mn is measured by gel permeation chromatography (GPC method).

The anodically electrochromic compounds which can be used in the electrochromic solution of the invention may be anodically electrochromic compounds (anode materials) commonly used in the art, i.e. oxidizable species. Exemplary anode materials include, but are not limited to: metallocenes, 5, 10-dihydrophenazines, phenothiazines, phenoxazines, carbazoles, triphendithiazines, triphendioxazines and derivatives thereof. In particular, exemplary anode materials include, but are not limited to: ferrocene, substituted ferrocenyl salts, phenazines, substituted phenazines, phenothiazines, substituted phenothiazines (including substituted dithiazines), thianthrenes, and substituted thianthrenes. In particular, exemplary anode materials include, but are not limited to: di-tert-butyl-diethylferrocene, 5, 10-dihydro-5, 10-Dimethylphenazine (DMP), 3,7, 10-trimethylphenothiazine, 2,3,7, 8-tetramethoxy-thianthrene, 10-methylphenothiazine, Tetramethylphenazine (TMP), bis (butyltriethylammonium) -p-methoxytriphendithiazine (TPDT) and 3, 10-dimethoxy-7, 14- (triethylammoniumbutyl) -triphendithiazinebis bis (tetrafluoroborate). Any anode material may be substituted with alkylammonium (-alkyl [ NR'₃]⁺Wherein each R 'is independently selected from H or alkyl), alkyl phosphonium (-alkyl [ PR'₃]⁺Wherein each R' is independently selected from H, alkyl or aryl), ether or ester functional substitution to help achieve higher concentrations of anode material in the electrochromic medium. In some embodiments, the anode material is substituted with an alkylammonium or alkylphosphonium.

Preferably, the anodically electrochromic compound that may be used in the electrochromic solution of the present invention is a phenazine or a phenazine derivative (i.e., a substituted phenazine), such as 5, 10-dihydro-5, 10-dimethylphenazine.

The cathodic electrochromic compounds that can be used in the electrochromic solution of the invention may be those commonly used in the art, i.e. reducible species. Exemplary cathode materials include, but are not limited to: viologens electrochromic compounds and metallocene complexes, and the like.

In the present invention, the viologen electrochromic compound has, for example, the following structural formula:

in the above formula, R¹And R²May be independently an alkyl, siloxanyl, hydroxyalkyl, carboxyalkyl, phosphonoalkyl, alkenyl or aralkyl group; r⁴、R⁶、R⁸And R¹⁰Can be separately H, OR²⁰、F、Cl、Br、I、CN、NO₂Alkyl or aryl; r²⁰Is H or alkyl; and X is an anion; r³、R⁵、R⁷And R⁹Can be separately H, OR²⁰、F、Cl、Br、I、CN、NO₂Alkyl or aryl;

optionally, R¹And/or R²Is a bridging group with other compounds of the above formula;

the anion X can be, but is not limited to, halide, borate, fluoroborate, tetraarylborate, hexafluorometal or metalloid, sulfate, sulfonate, sulfonamide, carboxylate, perchlorate, tetrachloroferrocinate, and the like. Illustrative X groups include, but are not limited to: f^—、Cl^—、Br^—、I^—、BF₄ ^—、PF₆ ^—、SbF₆ ^—、AsF₆ ^—、ClO₄ ^—、SO₃CF₃ ^—、N(CN)₂ ^—、N(CF₃SO₂)₂ ^—、C(CF₃SO₂)₃ ^—、N(SO₂C₂F₅)₂ ^—、^—Al(OC(CF₃)₃)₄Or^—BAr₄Wherein Ar is aryl or fluorinated aryl. In some embodiments, X is tetrafluoroborate or a bis (trifluoromethylsulfonyl) imide anion.

Further definitions of the groups in the above formulae are found in CN109564372A, and all preferred viologen structures in CN109564372A are also applicable in this application.

Preferably, the cathodic electrochromic compounds that can be used in the electrochromic solutions of the present invention are viologen-based electrochromic compounds, such as 1,1 '-dimethyl-4, 4' -bipyridyl bis (tetrafluoroborate), obtained by ion exchange using the commercially available product (Merck & Co)1, 1-dimethyl-4, 4-bipyridyl dichloride hydrate.

The solvent that can be used in the electrochromic solution of the present invention may be a solvent commonly used in the art without particular limitation. For example, solvents may include, but are not limited to, 3-methyl sulfolane, dimethyl sulfoxide, dimethylformamide, tetraglyme, and other polyethers; alcohols, such as ethoxyethanol; nitriles such as acetonitrile, glutaronitrile, 3-hydroxypropionitrile and 2-methylglutaronitrile; ketones, including 2-acetylbutyrolactone and cyclopentanone; cyclic esters including beta-propiolactone, gamma-butyrolactone, gamma-valerolactone; propylene carbonate, ethylene carbonate; an oligoether; ionic liquids, such as pyridinium-, imidazolium-, and pyrrolidinium compounds; and mixtures of any two or more such solvents.

In the present invention, the total weight of the polyisocyanate and the at least one polyol is from about 5 to 30 weight percent, preferably from 5 to 20 weight percent, more preferably from 5 to 15 weight percent, based on the total weight of the composition; the amount of the polyisocyanate is 0.5 to 15% by weight, preferably 0.8 to 10% by weight, more preferably 0.8 to 7% by weight; the total amount of the at least one high molecular weight polyol and the at least one low molecular weight polyol is 0.5 to 15 wt.%, preferably 2 to 12 wt.%, more preferably 3 to 10 wt.%.

In the present invention, the total weight of the anodic and cathodic electrochromic compounds is from 0.5 to 15% by weight, preferably from 0.5 to 5% by weight, based on the total weight of the composition; the amount of the anodic electrochromic compound is 0.1 to 10 wt%, preferably 0.2 to 7 wt%, more preferably 0.3 to 5 wt%; the amount of the cathodic electrochromic compound is 0.1 to 10% by weight, preferably 0.2 to 7% by weight, more preferably 0.3 to 5% by weight.

In the present invention, the amount of the solvent is 60 to 95% by weight, preferably 80 to 95% by weight, based on the total weight of the composition.

The concentration of the anodic and cathodic electrochromic compounds in the electrochromic layer can be adjusted to meet different color changing needs. Typically, the concentration of the anodic electrochromic compound in the electrochromic layer is in the range of about 1mmol/l (mM) to about 500mmol/l (mM), preferably in the range of about 1mM to about 100mM, more preferably in the range of about 1mM to about 70mM, more preferably in the range of about 1mM to about 50mM, e.g., 5mM, 10mM, 20mM, 30mM or 40mM, based on the total amount of all components of the electrochromic layer.

Typically, the concentration of the cathodic electrochromic compound in the electrochromic layer is in the range of about 1mM to about 500mM, preferably in the range of about 1mM to about 100mM, more preferably in the range of about 1mM to about 70mM, more preferably in the range of about 1mM to about 50mM, for example 5mM, 10mM, 20mM, 30mM or 40mM, based on the total amount of all components of the electrochromic layer.

In addition to the above-described anodic electrochromic compound, cathodic electrochromic compound and solvent, the composition of the present invention may further include, as adjuvants, for example, light absorbers, reducing compounds, light stabilizers, heat stabilizers, antioxidants, oxygen scavengers, viscosity modifiers, toners, redox buffers, curing catalysts, and the like, and mixtures of two or more thereof.

As adjuvants, exemplary UV stabilizers include, but are not limited to, acrylic acid 2-ethyl-2-cyano-3, 3-diphenyl ester; acrylic acid (2-ethylhexyl) -2-cyano-3, 3-diphenyl ester; 2- (2 '-hydroxy-4' -methylphenyl) benzotriazole; 3- [3- (2H-benzotriazol-2-yl) -5- (1, 1-dimethylethyl) -4-hydroxyphenyl]Pentyl propionate; 2, 4-dihydroxybenzophenone; 2-hydroxy-4-methoxybenzophenone; and 2-ethyl-2' -ethoxyaniline. Exemplary reducing compounds may include hydroquinones, such as, but not limited to, tetramethylhydroquinone. Exemplary redox buffers include, but are not limited to, those disclosed in U.S. patent No. 6,188,505, metallocene (e.g., substituted ferrocene) and metallocene complex (e.g., ferrocenium) compounds. Exemplary antioxidants include501(Everlight Chemical Industrial Corp). An exemplary curing catalyst includes dibutyltin diacetate.

In the present invention, the total amount of the adjuvant used is about 1 to 5% by weight, preferably 2 to 4% by weight, based on all components of the solution-type electrochromic layer.

The above compositions are mixed and cured at elevated temperatures, for example 60-100 c, to form a gelled electrochromic layer.

Electrochromic device

Yet another aspect of the present invention provides an electrochromic device including

-a first transparent substrate provided with a transparent conductive layer;

-a second substrate provided with a conductive reflective layer; and

-a solution-type electrochromic layer formed from the composition of the invention, located between the first transparent substrate and the second substrate.

In the present invention, at least one of the two substrates is transparent to at least a certain wavelength of visible light, similar to the substrates commonly used in the art. The inner sides of the two substrates facing each other are coated with an electrode layer in contact with the solution, which serves as an electrode in contact with the solution and is capable of conducting electricity. Since at least one of the two substrates is transparent for at least a certain wavelength of visible light, the electrode layer of the transparent substrate is also transparent for at least a certain wavelength of visible light. Accordingly, the other of the two substrates may be transparent or opaque, e.g. may have a reflective layer.

In the present invention, the term "transparent" means that the transmittance of visible light is at least 70%, preferably at least 80%, more preferably at least 90%, more preferably 95%, more preferably 100%.

Preferably, the first transparent substrate includes, but is not limited to, inorganic glass or organic glass, in particular borosilicate glass, soda lime glass, natural and synthetic polymeric resins, plastics and/or composites including polyesters (e.g. PET), Polyimides (PI), polycarbonates, polysulfones, polyethylene naphthalate (PEN), Ethylene Vinyl Acetate (EVA), acrylate polymers, and the like. Other transparent materials may also be used in the present invention as long as they meet the application requirements of the device.

The thickness of the first transparent substrate may be adjusted depending on the particular application of the electrochromic device. Typically, the first transparent substrate has a thickness in a range from about 0.001 millimeters (mm) to about 12.7mm, for example, in a range from about 0.01mm to about 1.50mm, or from about 0.03mm to about 1.00 mm.

Preferably, the transparent conductive layer on the first transparent substrate includes, but is not limited to, an indium tin oxide film layer, a zinc oxide film layer, a fluorine-doped indium tin oxide film layer, a fluorine-doped tin oxide film layer, or a fluorine-doped zinc oxide film layer.

In the present invention, the second substrate may be made of a similar material to the first substrate, except that the conductive coating on the second substrate need not be transparent, e.g., the conductive coating may be transparent, transflective, or reflective. The term "transflective" refers to having a non-zero level of transmission and also having a non-zero level of reflectivity for light in a specified spectral region. That is, the transparency of the second substrate is not essential, and the second substrate may be a metal.

The thickness of the second substrate can be adjusted depending on the particular application of the electrochromic device. Typically, the thickness of the second substrate may be in the range of about 0.001mm to about 12.7mm, for example in the range of about 0.03mm to about 1.50mm, or about 0.65mm to about 1.00 mm.

Preferably, the conductive reflective layer on the second substrate includes a chromium plating film layer, a silver plating film layer, a palladium plating film layer, a ruthenium plating film layer, a rhodium plating film layer, a platinum plating film layer, or a gold plating film layer.

The transparent conductive layer on the first substrate and the conductive reflective layer on the second substrate may be formed using a conventional technique in the art.

The distance between the first substrate and the second substrate is adjusted according to the specific application of the electrochromic device. Typically, the distance is less than 160 μm, for example, a distance in the range of about 50 μm to about 160 μm, about 60 μm to about 150 μm, about 120 μm to about 150 μm.

The solution-type electrochromic layer of the present invention is located between the first substrate and the second substrate. Generally, in order to dispose the solution type electrochromic layer between the first and second substrates, one or more cavities are formed between the first and second substrates using a sealing member. Pouring a composition for forming a solution-type electrochromic layer into the one or more cavities.

The sealing member used in the present invention may be a sealing member conventional in the art, for example, the sealing member is formed of a sealant. The sealant used in the present invention may be a sealant conventionally used in the art, such as epoxy resin, acrylic resin, and hybrid resin sealant.

In addition, in order to maintain the space between the first substrate and the second substrate, glass sand may be included in the sealant as a support. The support is insoluble in the solvent of the solution-type electrochromic layer and does not adversely affect the electrochromic process.

The electrochromic device of the present invention may be prepared according to a conventional method in the art. Generally, a first substrate 1 provided with a transparent conductive layer (e.g., a transparent conductive film) 2 and a second substrate 6 provided with a conductive reflective layer (e.g., a conductive reflective film) 5 are bonded together with a sealing member (e.g., a sealant) 3, and then cured and molded at a high temperature to form a cavity 4, while leaving a filling hole 7, a composition for forming a solution-type electrochromic layer is filled from the filling hole 7, and then sealed with an acrylic resin, and cured at an elevated temperature, e.g., 60 to 100 ℃, to form a gel, thereby obtaining an electrochromic device.

Examples

The present invention is described below by way of examples, but the scope of the present invention is not limited by these examples.

Materials used in the examples:

#1 composition for Forming solution-type electrochromic layer (present invention)

#2 composition for Forming solution-type electrochromic layer (present invention)

#3For forming solution typeComposition of electrochromic layer (invention)

#4 composition for Forming solution-type electrochromic layer (comparative example)

#5 composition for Forming solution-type electrochromic layer (comparative example)

#6 composition for Forming solution-type electrochromic layer (comparative example)

Application example 1 (invention):

the method comprises the steps of adopting a first substrate which is 15cm multiplied by 5cm and is plated with an ITO film and a second substrate which is 15cm multiplied by 5cm and is plated with a chromium film, bonding the first substrate and the second substrate by using epoxy resin frame glue at a distance of 125-149 mu m, baking for 1 hour at 150 ℃ to form a cavity, reserving a pouring hole 7, pouring the composition for forming the solution type electrochromic layer of the No. 1 in the invention from the pouring hole 7, heating for 1 hour at 85 ℃ to solidify to form gel, and sealing by using acrylic resin glue to obtain the electrochromic device.

Application example 2 (invention):

except using #2Composition for forming solution-type electrochromic layerExcept for this, the same as in application example 1.

Application example 3 (invention):

except using #3Composition for forming solution-type electrochromic layerExcept for this, the same as in application example 1.

Application comparative example 1:

except using #4Composition for forming solution-type electrochromic layerExcept for this, the same as in application example 1.

Application comparative example 2:

except using #5Composition for forming solution-type electrochromic layerExcept for this, the same as in application example 1.

Application comparative example 3:

except using #6Composition for forming solution-type electrochromic layerExcept for this, the same as in application example 1.

Performance testing

Resistance to steam boiling

The electrochromic devices of the present invention and the comparative example were placed under saturated water vapor at a temperature of 100 ℃ and a pressure of 1.5atm, respectively, and appearance changes of the sealant and the color-changing layer were observed, and the experimental results were as follows:

in the above experiment, application example 1 corresponds to application comparative example 1, application example 2 corresponds to application comparative example 2, and application example 3 corresponds to application comparative example 3, and it can be seen from the above experimental results that in three experiments, the combined use of a high molecular weight polyol and a low molecular weight polyol as components of a color-changing layer composition can significantly improve the steam boiling resistance of an electrochromic device, thereby improving weather resistance and temperature impact resistance, relative to a comparative example using only a high molecular weight polyol.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit of the invention. All such variations and modifications are to be considered within the scope of the claims of the present application.