An electro-optical film containing a non-protonic polar solvent-dispersed and polarized non-linear optical chromophore, and an electro-optical device including one or more electro-optical films

Abstract

Nonlinear optical chromophore compositions are provided that exhibit a lyotropic nematic liquid crystal phase in polar organic solvents and a mechanical anisotropy effect that allows the formation of non-centrosymmetric chromophore-polymer matrices without the application of an electric field.

Description

Technical Field

[0001] Cross - reference to related applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 288,089, filed on December 10, 2021, the entire content of which is incorporated herein by reference.

Background Art

[0002] Non - linear optical (NLO) chromophores provide electro - optical (EO) activity in poled polymer electro - optical devices. Electro - optical polymers have been studied for many years as alternatives to inorganic materials such as lithium niobate in electro - optical devices. Electro - optical devices can include, for example, external modulators for telecomm, datacom, RF photonics, and optical interconnections. Polymer electro - optical materials show great potential for core applications in a wide range of next - generation systems and devices, including electro - optical modulators, optical switches, phased - array radars, satellite and optical fiber communications, cable television (CATV), optical gyroscopes for aviation and missile guidance, electronic countermeasure (ECM) systems, backplane interconnections for high - speed computing, ultra - high - speed analog - to - digital conversion, landmine detection, radio - frequency photonics, spatial light modulation, and all - optical (light - switching - light) signal processing.

[0003] Many NLO molecules (chromophores) with high polymer electro - optical properties have been synthesized. The product of the molecular dipole moment (μ) and the hyperpolarizability (β) is often used as a measure of the electro - optical performance of the molecule due to its involvement in material processing. See Patent Document 1 titled “Dalton et al., ‘New Class of High Hyperpolarizability Organic Chromophores and Process for Synthesizing the Same’”.

[0004] Nevertheless, the microscopic molecular hyperpolarizability (β) into the macroscopic material hyperpolarizability (χ 2) It was extremely difficult to translate. This is because the auxiliary components (chromophores) of the molecule must be incorporated into NLO materials that exhibit (i) high macroscopic nonlinearity and (ii) sufficient temporary, thermal, chemical, and photochemical stability. High electro-optical activity and the stability of electro-optical activity, also known as "stability over time," are important in commercially viable devices. By increasing the concentration of the nonlinear optical chromophore in the host polymer and enhancing the electro-optical properties of the chromophore, the electro-optical activity of the electro-optical polymer can be increased. However, some methods of increasing the chromophore concentration may reduce stability over time. Simultaneously solving these two problems is regarded as the ultimate obstacle to the widespread commercialization of EO polymers in many devices and systems.

[0005] Due to the poor cohesion of NLO chromophores, the production of high hyperpolarizability materials (χ 2 ) is limited. Commercially viable materials must contain a large molecular density of chromophores with a desired molecular moment statistically oriented around a single material axis. To achieve such a mechanism, the charge transfer (dipole) nature of the NLO chromophore is usually developed by applying an external electric field during material processing to cause localization of the low-energy state favorable to the non-centrosymmetric dimension. Unfortunately, even when the chromophore density is moderate, the molecules form multi-molecular bipolar bonds (centrosymmetric) aggregates that cannot be removed via the actual electric field energy. To overcome this problem, non-aggregating bipolar chromophores are usually incorporated into a cooperative material structure by constructing a physical barrier (e.g., anti-packing steric groups) that limits the relationship between neighboring molecules.

[0006] Therefore, a high glass transition temperature (T g) is considered beneficial in the art for many to produce non-linear optical chromophores containing materials. Materials with a high glass transition temperature exhibit improved thermal stability and maintain their macroscopic electro-optical properties to a greater extent than materials with a low glass transition temperature. However, materials with such elevated glass transition temperatures need to be raised to very high temperatures during the poling process to achieve sufficient alignment. However, the need to achieve such high temperatures is costly and time-consuming, resulting in inefficient poling.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Patent Document 11

Patent Document 12

[0008] [Non-Patent Document 1] Chia-Chi Teng, Measuring Electro-Optic Constants of a Poled Film, in Nonlinear Optics of Organic Molecules and Polymers, Chp. 7, 447-49 (Hari Singh Nalwa & Seizo Miyata eds., 1997) [Non-Patent Document 2] C. W. Thiel, "For- wave Mixing and Its Applications,"www.physics.montana.edu.students.thiel.docs / FWMixing.pdf, [Summary of the Invention]

[0009] The present invention generally relates to non-linear optical chromophores that form lyotropic mixtures in solvents and exhibit liquid crystal properties. Accordingly, various embodiments of the present invention can provide an improvement in the polarization efficiency.

[0010] Various embodiments of the present invention exhibit liquid crystal properties and form a lyotropic composition when mixed with a solvent. For example, in certain embodiments, the chromophore exhibits a lyotropic nematic liquid crystal phase in a polar organic solvent. The resulting liquid crystal properties provide a mechanical anisotropy effect that forms a non-centrosymmetric chromophore-polymer matrix without the application of an electric field. In accordance with various embodiments described herein, a sufficient electro-optic coefficient (r 33 ) can be mechanically induced, and the need to apply a polarization temperature and an electric field, typically 170 °C and 100 v / pm, can be reduced. The liquid crystal properties and the lyotropic composition allow for mild process conditions and thus high polarization efficiency.

[0011] Various embodiments of the present invention include a non-linear optical chromophore represented by the general formula (I), D-Π-A (I) wherein D represents an organic electron donor group, A represents an organic electron acceptor group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D, The organic electron donor group D comprises a tetrahydrocarbazole moiety linked to the Π bridge by a carbon atom in the tetrahydro 6-membered carbon ring of the tetrahydrocarbazole moiety, and the hydrogen linked to the nitrogen in the tetrahydro 5-membered ring of the carbazole moiety is substituted with a substituent R.

[0012] Various embodiments of the present invention include a lyotropic composition comprising a non-linear optical chromophore represented by the general formula (I) and a solvent.

[0013] Various embodiments of the present invention include a thin film formed from a composition as described herein. Various embodiments of the present invention include an electro-optical device comprising a thin film as described herein.

[0014] Other aspects, features, and advantages will become apparent from the following disclosure, which includes a detailed description, preferred embodiments, and the appended claims.

[0015] The foregoing summary, as well as the following detailed description of the preferred embodiments of the present invention, will be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the present invention, the presently preferred embodiments are shown in the drawings. It should be understood, however, that the invention is not limited to the exact constructions and means shown.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2a

Figure 2b

Figure 2c

Modes for Carrying Out the Invention

[0017] [Detailed Description of the Invention] As used herein, the singular terms "a" and "the" are synonymous and used interchangeably with "one or more" and "at least one" unless specifically indicated by the word and / or context. Thus, for example, the expressions "a solvent" or "the solvent" in this specification or the appended claims may refer to a single solvent or more than one solvent or a mixture thereof. As a further example, not limited to only multiple electron donor groups, the expressions "an electron donor group" or "the electron donor group" in this specification or the appended claims may be an expression of a single electron donor group or more than one electron donor group (e.g., "D" in any molecular formula herein represents two or more electron donor groups, both of which may be bonded to the Π bridge). Further, unless otherwise specified, all numerical values are understood to be modified by the word "about".

[0018] As used herein, the term "nonlinear optical chromophore" (NLOC) refers to a molecule or a portion of a molecule that produces a nonlinear optical effect when irradiated with light. A chromophore is any molecular unit in which a nonlinear optical effect is produced by interaction with light. The desired effect may occur at the resonance wavelength or the non-resonance wavelength. The activity of a particular chromophore in a nonlinear optical material is expressed as its hyperpolarizability, which is directly related to the molecular dipole moment of the chromophore. Various embodiments of the NLO chromophores of the present invention are structures useful for producing an NLO effect.

[0019] Nonlinear optical chromophores according to various embodiments of the present invention exhibit liquid crystal properties and form lyotropic compositions when mixed with a solvent. Nonlinear optical chromophores according to various embodiments of the present invention exhibit a high glass transition temperature and, when mixed with a solvent to form a lyotropic composition, exhibit J-aggregates of self-alignment formation, in contrast to the head-to-tail alignment shown by the prior art (i.e., H-aggregates). Nonlinear optical chromophores according to various embodiments of the present invention are combined with a solvent (i.e., without the addition of a matrix material or host polymer) to form a lyotropic composition, and with additional shear, at least partial self-alignment of the nonlinear optical chromophores is achieved, forming a highly ordered and highly packed state. In various embodiments of the present invention, no further polarization is required to provide a nonlinear optical thin film for use in an electro-optical device, such as a modulator. In various embodiments of the present invention, the solvent can be removed under controlled conditions to maintain the chromophores in a highly ordered and highly packed state. In various embodiments of the present invention, conventional polarization processes can also be carried out, including applications in the art across chromophore thin films. Nonlinear optical chromophores according to various embodiments of the present invention can be combined with a matrix material or host polymer and a solvent to form a lyotropic composition. In various embodiments of the present invention, high boiling point solvents can be used for polarization according to the method described in Patent Document 2 filed on December 3, 2021, the entire contents of which are incorporated herein by reference.

[0020] The first hyperpolarizability (β) is one of the most common and useful NLO properties. Higher order hyperpolarizabilities are useful in other applications, such as all optical (light-switching-light) applications. By performing the following tests, materials such as compounds or polymers have the property of first hyperpolarizability and a sufficient electro-optic coefficient (r 33It is possible to determine whether a material contains a non-linear optical chromophore (which is a β function). First, a material in the form of a thin film is placed in an electric field to align the dipoles. This can be achieved, for example, by sandwiching a film of the material between electrodes such as an indium tin oxide (ITO) substrate, a gold film, or a silver film.

[0021] While heating the material near its glass transition temperature (T g ), a potential is applied to the electrodes to generate a polarization adjustment electric field. After a suitable period of time, the temperature is gradually lowered while maintaining the polarization adjustment electric field. Alternatively, the material can also be polarized by the corona polarization method, in which the polarization adjustment electric field is provided by a charged needle at a suitable distance from the material film. In any case, the dipoles in the material tend to align with the electric field.

[0022] The non-linear optical properties of the polarized material are tested as follows. Polarized light, which is often from a laser, is passed through the polarized material and then through a polarization filter and a light intensity detector. If the intensity of the light received by the detector changes when the potential applied to the electrodes changes, the material contains a non-linear optical chromophore and has a refractive index that is electro-optically variable. The technique for measuring the electro-optical constant of a polarized film containing a non-linear optical chromophore is discussed in more detail in Non-Patent Document 1, which is incorporated herein by reference in its entirety, provided that in the event of any disclosure or definition that is inconsistent with the present application, the disclosure or definition in this specification shall be considered to take precedence.

[0023] The relationship between the change in the applied potential and the change in the refractive index of the material can be represented by its EO coefficient r 33 . This effect is generally referred to as the electro-optical effect, i.e., the EO effect. A device containing a material whose refractive index changes in response to a change in the applied potential is called an electro-optical (EO) device.

[0024] The second-order hyperpolarizability (γ) or the third-order susceptibility (χ (3))(0) is a typical measure of third-order NLO activity. There are several methods for measuring these properties, but degenerate four-wave mixing (DFWM) is very common. See Non-Patent Document 2. The entire content thereof is incorporated herein by reference. See Patent Document 3. The entire content thereof is incorporated herein by reference. A method for evaluating the third-order NLO properties of thin films known in the art as degenerate four-wave mixing (DFWM) can be used. In FIG. 4 of Patent Document 4, beams 1 and 2 are picosecond coherent pulses and are absorbed by an NLO film deposited on a glass substrate. Beam 3 is a weak beam with a slightly delayed wavelength identical to that of beams 1 and 2. Beam 4 is generated by wave mixing diffracted from a temporary holographic grating generated by the interference of beams 1 and 2 within the material of the NLO film. Beam 3 can be a "control" beam at a communication wavelength that generates a "signal" beam at a frequency not absorbed by the NLO material.

[0025] The non-linear optical chromophores according to various embodiments of the present invention have the general formula (I). D-Π-A (I) In the formula, D represents an organic electron donor group, A represents an organic electron acceptor group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D. The terms electron donor group (donor or "D"), Π bridge (bridging group or Π), and electron acceptor group (acceptor or "A"), as well as general synthetic methods for forming D-Π-A chromophores, are known in the art and are described, for example, in Patent Document 5, Patent Document 6, Patent Document 7, and Patent Document 8 and Patent Document 9 filed on June 25, 2021, the entire contents of which are incorporated herein by reference.

[0026] The acceptor is an atom or group of atoms having a low reduction potential, and the atom or group of atoms can receive electrons from the donor via a Π bridge. The acceptor (A) has a higher electron affinity than the donor (D). As a result, at least in the absence of an external electric field, the chromophore is generally polarized with a relatively high electron density on the acceptor (D) in the ground state. Typically, the acceptor group contains at least one electronegative heteroatom that is part of a pi bond (double bond or triple bond). As a result, resonance structures can be drawn, which moves the electron pair of the pi bond to the heteroatom while reducing the multiplicity of the pi bond (i.e., the double bond is formally converted to a single bond or the triple bond is formally converted to a double bond), so that the heteroatom acquires a formal negative charge. This heteroatom can be part of a heterocyclic ring. Exemplary acceptor groups include, but are not limited to, -NO2, -CN, -CHO, COR, CO2R, -PO(OR)3, -SOR, -SO2R, and -SO3R (where R is alkyl, aryl, or heteroaryl). The total number of heteroatoms and carbons in the acceptor group is about 30, and the acceptor group may be further substituted with alkyl, aryl, and / or heteroaryl.

[0027] Electron-withdrawing groups "A" (also referred to in the literature as electron-withdrawing groups) suitable for the non-linear optical chromophores according to various embodiments of the present invention include those described in Patent Documents 10, 11, 12, 13, 14, and 15 (collectively referred to as "prior publications"), the entire contents of which are incorporated herein by reference. Also included are those described in Patent Documents 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, and 33 and Patent Document 34 filed on June 25, 2021, the entire contents of which are incorporated herein by reference.

[0028] In various non-linear optical chromophores according to various preferred embodiments of the present invention, suitable electron-withdrawing groups have the general formula (I a ), including

[0029]

Chemical formula

[0030] In the formula, R 2 and R 3 are each independently H, substituted or unsubstituted C1-C 10 alkyl, substituted or unsubstituted C2-C 10 alkenyl, substituted or unsubstituted C2-C 10 alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH2) n -O-(CH2) n (n is from 1 to 10), representing a moiety selected from the group consisting of. As used herein,

[0031]

Chemical formula

[0032] represents a bonding point to another part of a larger molecular structure. In various preferred embodiments, one or both of R 2 and R 3 represent a halogen-substituted moiety. Halogen substitution may refer to mono, di, tri, and higher degrees of substitution. In various preferred embodiments, one of R 2 and R 3 represents a halogen-substituted alkyl moiety, and the other represents an aromatic moiety. In various preferred embodiments, one of R 2 and R 3 represents a halogen-substituted aromatic moiety, and the other represents an alkyl moiety. In various preferred embodiments, the electron-withdrawing group can be represented by the following formula.

[0033]

Chem.

[0034] In various preferred embodiments, the electron-withdrawing group can be represented by the following formula.

[0035]

Chem.

[0036] In various preferred embodiments, the electron-withdrawing group can be represented by the following formula.

[0037]

Chem.

[0038] The donor contains an atom or group of atoms having a low oxidation potential, and the atom or group of atoms can donate electrons to the acceptor "A" via a Π bridge. The donor (D) has a lower electron affinity than the acceptor (A), and as a result, in the absence of at least an external electric field, the chromophore is generally polarized with a relatively low electron density on the donor (D).

[0039] The donor according to various preferred embodiments of the present invention may contain a tetrahydrocarbazole moiety represented by the general formula (II).

[0040]

Chem.

[0041] In the formula, R 1 represents a moiety other than hydrogen, and R 2 represents a moiety selected from hydrogen, a halide, an alkoxy group, a branched or unbranched alkyl group, and an aryl group, and R 3 represents a moiety selected from hydrogen and a branched or unbranched alkyl group, and R 4represents a part selected from hydrogen and an alkyl group (branched or unbranched), R 5 can represent a fused aliphatic or aromatic ring optionally having 3 to 5 carbon atoms. In various embodiments, R 3 and R 4 can represent the same part. In various embodiments, R 1 represents a part selected from the group consisting of a branched alkyl group and an aryl group. In various embodiments, R 1 represents a part selected from a substituted or unsubstituted benzyl group.

[0042] Donors according to various embodiments of the present invention may include a tetrahydrocarbazole moiety represented by general formula (IIa).

[0043]

Chemical formula

[0044] In the formula, R represents a part other than hydrogen.

[0045] In various embodiments, the donor includes a tetrahydrocarbazole moiety represented by general formula (II), and R 1 can represent an aryl-containing part. In various embodiments, R 1 can represent an aryl group further substituted with a silyl group. In various embodiments, R 1 can represent an aryl group further substituted with a triaryl-substituted silyl group. In various embodiments, R 1 can represent 4-(triphenylsilyl)-phenylmethyl.

[0046] In various embodiments, the donor comprises a tetrahydrocarbazole moiety represented by general formula (IIa), and R may represent an aryl-containing moiety. In various embodiments, R may further represent an aryl group substituted with a silyl group. In various embodiments, R may further represent an aryl group substituted with a triaryl-substituted silyl group. In various embodiments, R may represent 4-(triphenylsilyl)-phenylmethyl.

[0047] "Π-bridging" includes atoms or groups of atoms that can delocalize electrons from an electron donor (as defined above) to an electron acceptor (as defined above) via the orbitals of the atoms during bridging. Such groups are very well known in the art. Typically, the orbitals are p-orbitals on double (sp 2 ) or triple (sp) bonded carbon atoms, such as those found in alkenes, alkynes, neutral or charged aromatic rings, and neutral or charged heteroaromatic ring systems. Further, the orbitals may be p-orbitals on atoms such as boron or nitrogen. Further, the orbitals may be p, d or f organometallic orbitals or hybrid organometallic orbitals. The atoms of the bridge containing the orbitals through which the electrons are delocalized are herein referred to as "critical atoms". The number of critical atoms within the bridge can be from 1 to about 30. The critical atoms may be substituted with organic or inorganic groups. The substituents may be selected for the purpose of improving the solubility of the chromophore in the polymer matrix, enhancing the stability of the chromophore, or for other purposes.

[0048] Suitable bridging groups (Π) for the non-linear optical chromophores according to general formula (I) of the present invention include those described in Patent Document 35, Patent Document 36, Patent Document 37, Patent Document 38, Patent Document 39, and Patent Document 40 filed on June 25, 2021, the entire contents of which are incorporated herein by reference.

[0049] In various preferred embodiments, the bridging group (Π) of the non-linear optical chromophore according to general formula (I) of the present invention comprises a bridging group of general formula (II a ).

[0050]

Chemical formula

[0051] In the formula, X represents a substituted or unsubstituted, branched or unbranched C2-C4 diyl moiety, a and b each independently represent an integer from 0 to 3, and z represents an integer from 0 to 3. In various embodiments, when a or b in general formula (II a ) is 1, the carbon-carbon double bond in the formula can be replaced by a carbon-carbon triple bond. Alternatively, in various preferred embodiments, the crosslinking group (Π) of the non-linear optical chromophore according to general formula (I) of the present invention comprises the crosslinking group of general formula (II b ).

[0052]

Chemical formula

[0053] X represents a substituted or unsubstituted, branched or unbranched C2-C4 diyl moiety. In various embodiments of the present invention, by covalently bonding one or more diamondoid groups to the crosslinking group according to general formula II a or II b , one or more diamondoid groups may be bonded to, for example, the sulfur atom or oxygen atom of a thiophene group, or may be bonded to one or more carbon atoms of X via an ether bond or a thioether bond.

[0054] In various preferred embodiments, the crosslinking group (Π) of the non-linear optical chromophore according to general formula (I) of the present invention comprises the crosslinking group of general formula (II c ).

[0055]

Chemical formula

[0056] In the formula, Y each independently represents a diamondoid-containing group that is covalently bonded to a crosslinking group via any of various linkages described herein including, but not limited to, ether linkages and thioether linkages, or Y each represents hydrogen, an alkyl group, an aryl group, an alkyl or aryl group bonded to sulfur or oxygen, or a branched or unbranched, optionally heteroatom-containing C1-C4 substituent, a and b each independently represent an integer from 0 to 3, z represents an integer from 1 to 3, arc A each independently represents a substituted or unsubstituted C2-C4 alkyl group, and together with the carbon having a Y substituent and its two adjacent carbon atoms forms a cyclic group. The substituted or unsubstituted C2-C4 alkyl group constituting arc A contains 1 to 4 hydrogen substituents, and each of the hydrogen substituents is a substituted or unsubstituted C1-C 10 alkyl, a substituted or unsubstituted C2-C 10 alkenyl, a substituted or unsubstituted C2-C 10 alkynyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocyclic ring, a substituted or unsubstituted heterocyclic ring, a substituted or unsubstituted cyclohexyl, and (CH2) n -O-(CH2) n (where n is from 1 to 10) and includes a moiety selected from the group consisting of. In various preferred embodiments, z represents 1. In various embodiments according to the present invention, the electron-donating group or electron-withdrawing group can include one or more covalently bonded diamondoid groups, and Y in general formula II c can represent any of the above substituents. In certain preferred embodiments, the chromophore may include an electron-donating group containing one or more covalently bonded diamondoid groups, preferably adamantyl, and the crosslinking group may include an isophorone group according to general formula II c .

[0057] In various preferred embodiments, the crosslinking group (Π) of the non-linear optical chromophore according to general formula (I) of the present invention includes the crosslinking group of general formula (II d ).

[0058] [Chemical formula]

[0059] In the formula, Y each independently represents a diamondoid-containing group that is covalently bonded to a crosslinking group via any of various bonds described herein including, but not limited to, ether bonds and thioether bonds, or Y is each hydrogen, an alkyl group, an aryl group, an alkyl or aryl group bonded to sulfur or oxygen, an aryl group directly linked by a carbon-carbon bond (e.g., adamantyl anisole) (optionally having a diamondoid group), a halogen, a halogenated alkyl group, a halogenated aryl group, or a branched or unbranched, optionally heteroatom-containing C1-C4 substituent, a and b each independently represent an integer from 0 to 3, and z represents an integer from 1 to 3. In various embodiments of the present invention, the electron-donating group or electron-withdrawing group can include one or more covalently bonded diamondoid groups, and in General Formula II d Y can represent any of the above substituents. In certain preferred embodiments, the chromophore may include one or more covalently bonded diamondoid groups, preferably an electron-donating group containing adamantyl, and the crosslinking group may include an isophorone group according to General Formula II d In various embodiments, the geminal methyl groups on the isophorone crosslink of General Formula II d each independently may instead be a substituted or unsubstituted C1-C 10 alkyl, a substituted or unsubstituted C2-C 10 alkenyl, a substituted or unsubstituted C2-C 10 alkynyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocyclic ring, a substituted or unsubstituted heterocyclic ring, a substituted or unsubstituted cyclohexyl, a halogen, a halogenated alkyl group (e.g., -CF3), a halogenated aryl and heteroaryl group (e.g., pentafluorothiophenol), and (CH2) n-O-(CH2) n (where n is from 1 to 10).

[0060] For example, the crosslinking group (Π) of the non-linear optical chromophore according to the general formula (I) of the present invention can include the following.

[0061]

Chemical formula

[0062] Specific examples of the non-linear optical chromophore according to various embodiments can include the following.

[0063]

Chemical formula

[0064]

Chemical formula

[0065]

Chemical formula

[0066]

Chemical formula

[0067] and

[0068]

Chemical formula

[0069] Various embodiments of the present invention include a lyotropic composition comprising a non-linear optical chromophore and a solvent as described herein. Suitable solvents for the lyotropic composition according to various embodiments of the present invention may include aprotic polar solvents and mixtures thereof. In various embodiments, a suitable solvent may include propylene carbonate.

[0070] Suitable solvents can be combined with the non-linear optical chromophore in any amount. In various embodiments, one or more solvents can be combined with the non-linear optical chromophore in an amount of about 25 wt% to about 75 wt%, and in various embodiments, about 35 wt% to about 65 wt%, and in various embodiments, about 40 wt% to about 60 wt%. In various embodiments, one or more solvents can be combined with the non-linear optical chromophore in an amount up to 50 wt%.

[0071] The lyotropic composition of the non-linear optical chromophore and solvent according to various embodiments of the present invention exhibits at least partial self-assembly. Such a composition can be efficiently polarized by applying a minimal voltage. In various embodiments, the lyotropic composition exhibits a high degree of self-assembly by shear so that polarization by application is not required. The lyotropic composition according to various embodiments of the present invention can form a thin film that is highly dense, highly filled, and highly ordered and is used in an electro-optical device. The thin film according to various embodiments of the present invention can be formed without external application or with application. In various embodiments, the thin film can be formed without application.

[0072] The present invention will be described in more detail with reference to the following non-limiting examples.

Example

[0073] Synthesis Example 1:

[0074] Step 1: Synthesis of triphenyl(p-tolyl)silane:

[0075]

Chemical formula

[0076] The dry RB flask (1) was charged with 1-bromo-4-methyl-benzene (9.93 mL, 0.0807 mol) and THF (200 mL), and then cooled to -78 °C in a dry ice / acetone bath. n-Butyllithium (2.50 mol / L, 32.3 mL, 0.0807 mol) was added at a rate such that the temperature did not rise above -55 °C (in 5 mL increments), and the reaction mixture was stirred at -78 °C for 2 hours under nitrogen.

[0077] Another RB flask (2) was emptied, then filled with nitrogen three times, charged with triphenylsilyl chloride (26.2 g, 0.0888 mol), emptied / filled with nitrogen three times, and stirred under vacuum at 60 °C for 1H. RB flask (2) was cooled, filled with nitrogen, then charged with THF (100 mL), and cooled to -78 °C.

[0078] The contents of flask (2) were cannulated into flask (1) by stable dropping, and the temperature rose by 5 °C. The reaction mixture was stirred under nitrogen and slowly warmed to room temperature.

[0079] The reaction mixture was diluted with DCM, washed with water and then brine, dried over MgSO4, and evaporated to give a white solid. It was stirred in hexane for 1H and filtered / washed with hexane (500 mL).

[0080] Triphenyl(p-tolyl)silane (25.4 g, 0.0725 mol, yield: 89.8%) was obtained as a white powder.

[0081] Step 2: Wall-Ziegler bromination reaction of triphenyl(p-tolyl)silane

[0082]

Chemical formula

[0083] The RB flask was charged with triphenyl(p-tolyl)silane (0 mmol / L, 0 mL, 0.0394 mol), N-bromosuccinimide (7.36 g, 0.0413 mol), 400 mL of DCM, and 2-[(E)-(1-cyano-1-methyl-ethyl)azo]-2-methyl-propanenitrile (0.323 g, 0.00197 mol). The reaction mixture was refluxed overnight under nitrogen. TLC indicated quantitative conversion to the bromide.

[0084] The reaction mixture was washed with water and then with brine, dried over MgSO4, and evaporated to give a yellowish-brown powder. This was triturated in hexane and filtered to give 3343-A, 13.8 g, and the filtrate was evaporated to give 3343-H, 3.49 g. The hexane fraction was chromatographed and eluted with hexane / ethyl acetate (3 - 5%). The appropriate fractions were combined and evaporated to give 3343-fraction-A-B. Fraction B was triturated in hexane and filtered to give 3343-B as a very white granular powder, 885 mg.

[0085] 4-[(Bromomethyl)phenyl]-triphenyl-silane (14.7 g, 0.0342 mol, yield: 87.0%) was obtained.

[0086] Step 3: Alkylation of 1,2,3,9-tetrahydrocarbazol-4-one

[0087]

Chemical Structure

[0088] The RB flask was charged with 4-[(bromomethyl)phenyl]-triphenyl-silane (13.8 g, 0.0321 mol), 1,2,3,9-tetrahydrocarbazol-4-one (5.95 g, 0.0321 mol) and 200 mL of DMF under nitrogen. The mixture was cooled to 0 °C and then sodium hydride (60%, 1.41 g, 0.0353 mol) was added. The reaction was stirred under nitrogen and slowly warmed to room temperature (RT). After a 2-hour reaction, the mixture was warmed and made homogeneous, and the product was allowed to stand for 15 minutes and then stirring was stopped. The reaction became a solid white paste.

[0089] The reaction was triturated in water and then filtered / washed with water. The organics were chromatographed and eluted with hexane / ethyl acetate (5%). The appropriate fractions were combined and evaporated to give an off-white solid. It was dissolved in DCM, hexane was added and the DCM was evaporated. The resulting solid was filtered.

[0090] 9-[(4-Triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-one (10.8 g, 0.0202 mol, yield: 63.0%) was obtained as a white solid.

[0091] Step 4: Alkylation of 9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-one with methylmagnesium bromide

[0092]

Chemical formula

[0093] The dry RB flask was charged with 9-benzyl-2,3-dihydro-1H-carbazol-4-one (6.18 g, 0.0224 mol) and 240 mL of THF under nitrogen. Methylmagnesium bromide (3.00 mol / L, 15.0 mL, 0.0449 mol) was added and the reaction mixture was stirred under nitrogen. After stirring over the weekend, the reaction mixture was diluted with DCM, washed with water (acidified with HCl to remove the emulsion, a distinct Grignard reaction with the addition of acidic water), then with brine, dried over MgSO4, and evaporated. The material was chromatographed and eluted with hexane / ethyl acetate (5%). The appropriate fractions were combined and evaporated.

[0094] 9-Benzyl-4-methyl-2,3-dihydro-1H-carbazol-9-ium; bromide (2.19 g, 0.00618 mol, yield: 27.5%) was obtained.

[0095] Step 5: Reaction of the donor, bridge, and acceptor to form chromophore 1 The RB flask was charged with (3E)-2-chloro-3-(hydroxymethylene)cyclohexene-1-carbaldehyde (0.403 g, 0.00233 mol), 2-[3-cyano-4-methyl-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.736 g, 0.00233 mol), and 12 mL of methanol. It was stirred at 40 °C for 1 hour under nitrogen. The methanol was evaporated, and then [4-[(4-methyl-2,3-dihydro-1H-carbazol-9-ium-9-yl)methyl]phenyl]-triphenyl-silane; bromide (1.43 g, 0.00233 mol) and 12 mL of DCM were added. The reaction mixture was stirred overnight at room temperature under nitrogen. The reaction mixture was applied to a silica gel column and eluted with DCM. The appropriate fractions were combined and evaporated to recover 391 mg of pure carbazolium, 3307-C. The product and residue were chromatographed and eluted with DCM. The appropriate fractions were combined and evaporated to obtain 1.11 g of 3307-P. It was triturated in warm methanol, cooled, filtered, and washed with methanol, and after drying, 0.752 g of 3307-A was obtained. The methanol was evaporated to obtain 3307-MeOH.

[0096] 2-[4-[(E)-2-[(3Z)-2-chloro-3-[(2Z)-2-[9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-ylidene]ethylidene]cyclohexen-1-yl]vinyl]-3-cyano-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (1.11 g, 0.00113 mol, yield: 48.4%): Chromophore 1 was obtained.

[0097]

Chemical Structure

[0098] Synthesis Example 2:

[0099] Using the donor group prepared in Synthesis Example 1, 9-benzyl-4-methyl-2,3-dihydro-1H-carbazol-9-ium; bromide, chromophore 2 was prepared as follows. The RB flask was charged with (3E)-2-chloro-3-(hydroxymethylene)-5-(trifluoromethyl)cyclohexene-1-carbaldehyde (0.349 g, 0.00145 mol), 2-[3-cyano-4-methyl-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.458 g, 0.00145 mol) and 12 mL of ethanol. It was stirred at 40 °C for 1 hour under nitrogen. The ethanol was evaporated, and then [[4-[(4-methyl-2,3-dihydro-1H-carbazol-9-ium-9-yl)methyl]phenyl]-triphenyl-silane; bromide (809 mg, 0.00132 mol) and 12 mL of DCM were added. The reaction mixture was stirred overnight at room temperature under nitrogen. The reaction mixture was applied to a silica gel column and eluted with DCM. The appropriate fractions were combined and evaporated. The product and residue were chromatographed and eluted with DCM. The appropriate fractions were combined and evaporated. This was triturated in warm methanol, cooled, filtered, and washed with methanol.

[0100] 2-[4-[(E)-2-[(3Z)-2-chloro-5-(trifluoromethyl)-3-[(2Z)-2-[9-[(4-triphenylsilylphenyl)methyl]-2,3-dihydro-1H-carbazol-4-ylidene]ethylidene]cyclohexen-1-yl]vinyl]-3-cyano-5-phenyl-5-(trifluoromethyl)-2-furylidene]propanedinitrile (0.595 g, 0.000566 mol, yield 42.9%) was obtained.

[0101]

Chemical Structure

[0102] Specific examples of the maximum absorption wavelength for embodiments of the chromophore

[0103] Chromophore 1 formed a lyotropic composition in combination with propylene carbonate at 50 wt%. The composition was sheared between two glass substrates and optical absorption analysis was performed over the visible and near-infrared spectra. Referring to Figure 1, the sheared sample (the curve having an absorption peak proximal to 1200 nm) showed a red shift and an overall shift in the near-infrared direction as indicated by its peak value. As shown in Figure 1, the sheared sample heated to 150 °C for a short period to remove the solvent did not show such a red shift. Such a red shift is evidence of the formation of J-aggregates showing at least partial self-assembly and anisotropy.

[0104] Chromophore 1 formed a lyotropic composition in combination with propylene carbonate at 50 wt%. The composition was placed between two glass substrates and subjected to polarized microscopy. Referring to Figures 2a - 2c, a red color was immediately observed in the sheared sample showing J-aggregate formation, at least partial self-assembly, and anisotropy. Figure 2c shows the sample between the two glass substrates before shearing. The formation of distinct micelles, which is evidence of lyotropic properties, was shown. Figure 2b shows that the sheared sample serves as evidence of a vivid red color. Such a red color is evidence of the formation of J-aggregates showing at least partial self-assembly and anisotropy. In Figure 2c, the sample heated to 100 °C to remove the solvent did not show a red color.

[0105] It will be understood by those skilled in the art that modifications can be made to the above-described embodiments without departing from the broad inventive concept. Accordingly, it is understood that the present invention is not limited to the specific embodiments disclosed and is intended to include modifications within the spirit and scope of the present invention as defined by the appended claims.

Claims

1. An electro-optical film comprising a non-linear optical chromophore dispersed and polarized in an aprotic polar solvent, wherein the non-linear optical chromophore is represented by the general formula (I), D-Π-A (I) wherein D represents an organic electron donor group, A represents an organic electron acceptor group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D, The organic electron donor group D comprises a tetrahydrocarbazole moiety linked to the Π bridge by a carbon atom in the tetrahydro 6-membered carbon ring of the tetrahydrocarbazole moiety, and the hydrogen linked to the nitrogen of the 5-membered ring of the carbazole moiety is substituted by a substituent R, and R represents a moiety other than hydrogen, an electro-optical film.

2. The tetrahydrocarbazole moiety is represented by the general formula (II), 【Chemical 1】 R represents a moiety other than hydrogen, the electro-optical film according to claim 1.

3. R represents a moiety containing an aromatic ring, the electro-optical film according to claim 2.

4. R represents a moiety containing an aromatic ring having a triarylsilyl substituent, the electro-optical film according to claim 3.

5. R represents a moiety containing an aromatic ring having a triarylsilyl substituent represented by the general formula (III), 【Chemical 2】 The electro-optical film according to claim 4.

6. A represents an electron-withdrawing group of the general formula (I a ), and [Chemical Formula 3] wherein R 2 and R 3 are each independently H, substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 alkenyl, substituted or unsubstituted C 2 -C 10 alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocycle, substituted or unsubstituted heterocycle, substituted or unsubstituted cyclohexyl, and (CH 2 ) n -O-(CH 2 ) n (n is 1 to 10), and represents a moiety selected from the group consisting of, the electro-optical film according to claim 1.

7. The non-linear optical chromophore is represented by the general formula (IV), [Chemical Formula 4] In the formula, R represents a substituent other than hydrogen, and R 2 and R 3 each independently represents H, a substituted or unsubstituted C 1 -C 10 alkyl, a substituted or unsubstituted C 2 -C 10 alkenyl, a substituted or unsubstituted C 2 -C 10 alkynyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocyclic ring, a substituted or unsubstituted heterocyclic ring, a substituted or unsubstituted cyclohexyl, and (CH 2 ) n -O-(CH 2 ) n (n is an integer from 1 to 10), Y represents hydrogen, a halogen, an alkyl group, an aryl group, an alkyl group or aryl group bonded to sulfur or oxygen, or a branched or unbranched, optionally heteroatom-containing C 1 to C 4 substituent, a and b each independently represent an integer from 0 to 3, z represents an integer from 1 to 3, and each arc A independently represents a substituted or unsubstituted C 2 -C 4 alkyl group, and forms a cyclic group together with the carbon having the Y substituent and its two adjacent carbon atoms. The electro-optical film according to claim 1.

8. An electro-optical device comprising one or more electro-optical films, each of the one or more electro-optical films containing a non-linear optical chromophore dispersed and polarized in an aprotic polar solvent, the non-linear optical chromophore being represented by the general formula (I), D-Π-A (I) wherein D represents an organic electron donor group, A represents an organic electron acceptor group having an electron affinity greater than that of D, and Π represents a Π bridge between A and D, The organic electron donor group D comprises a tetrahydrocarbazole moiety linked to the Π bridge by a carbon atom in the tetrahydro 6-membered carbon ring of the tetrahydrocarbazole moiety, and the hydrogen linked to the nitrogen of the 5-membered ring of the carbazole moiety is substituted by a substituent R, and R represents a moiety other than hydrogen, An electro-optical device.

9. The tetrahydrocarbazole moiety is represented by the general formula (II), 【Chemical Formula 5】 R represents a moiety other than hydrogen, the electro-optical device according to claim 8.

10. R represents a moiety containing an aromatic ring, the electro-optical device according to claim 9.

11. The electro-optical device according to claim 10, wherein R represents a portion containing an aromatic ring having a triaryl-substituted silyl substituent.

12. The electro-optical device according to claim 11, wherein R represents a portion containing an aromatic ring having a triaryl-substituted silyl substituent represented by the general formula (III). ​

13. A represents an electron-withdrawing group of the general formula (I a ), and 【Chemical 7】 wherein R 2 and R 3 each independently represents a group selected from the group consisting of H, substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 alkenyl, substituted or unsubstituted C 2 -C 10 alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted alkylaryl, substituted or unsubstituted carbocyclic ring, substituted or unsubstituted heterocyclic ring, substituted or unsubstituted cyclohexyl, and (CH 2 ). n -O-(CH 2 ). n (n is from 1 to 10), the electro-optical device according to claim 8.

14. The non-linear optical chromophore is represented by the general formula (IV), [Chemical Formula 8] In the formula, R represents a substituent other than hydrogen, and R 2 and R 3 each independently represent H, a substituted or unsubstituted C 1 -C 10 alkyl, a substituted or unsubstituted C 2 -C 10 alkenyl, a substituted or unsubstituted C 2 -C 10 alkynyl, a substituted or unsubstituted aryl, a substituted or unsubstituted alkylaryl, a substituted or unsubstituted carbocyclic ring, a substituted or unsubstituted heterocyclic ring, a substituted or unsubstituted cyclohexyl, and (CH 2 ) n -O-(CH 2 ) n (where n is an integer from 1 to 10), Y represents hydrogen, a halogen, an alkyl group, an aryl group, an alkyl group or aryl group bonded to sulfur or oxygen, or a branched or unbranched, optionally heteroatom-containing C 1 to C 4 substituent, a and b each independently represent an integer from 0 to 3, z represents an integer from 1 to 3, and each arc A independently represents a substituted or unsubstituted C 2 -C 4 alkyl group, and forms a cyclic group together with the carbon having the Y substituent and its two adjacent carbon atoms. The electro-optical device according to claim 8.

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