JP2007099739A - Compound, organic functional material, and organic functional element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compound capable of maintaining a high functional performance and excellent in heat resistance and stability. <P>SOLUTION: This compound is expressed by general formula (1) (Z<SP>1</SP>, Z<SP>2</SP>and Z<SP>3</SP>are each an aromatic group; L is a bivalent π conjugate group or a single bond; and Y<SP>1</SP>is a bivalent organic group; provided that any two or more of the aromatic groups expressed by Z<SP>1</SP>, Z<SP>2</SP>and Z<SP>3</SP>and the bivalent π conjugate group may be bonded to each other and form a condensed ring). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic electrophotographic photosensitive member that can be used for a copying machine, a printer, electronic paper, and the like; an organic electroluminescent device that can be used for an electronic display board, a display, and the like; a light modulator useful in optical information communication, optical information processing, and the like; The present invention relates to an organic functional element that exhibits functions related to light and / or electricity, such as an organic nonlinear optical element that can be used in an optical switch, an optical integrated circuit, an optical computer, an optical memory, a wavelength conversion element, a holographic element, and the like. Furthermore, the present invention relates to an organic functional material that is a key material for forming the organic functional element, and a compound that can be suitably used as the organic functional material.

  Most of the functional elements such as wavelength conversion elements, optical modulators, optical switches, etc., which are important in the fields of optical information communication, optical information processing, and imaging using light, use nonlinear optical materials, especially second-order nonlinear optical materials. Is embodied by. Inorganic nonlinear optical materials such as lithium niobate and potassium dihydrogen phosphate have already been put into practical use and widely used as secondary nonlinear optical materials. In recent years, however, these nonlinear materials have high nonlinear optical performance. Attention has been focused on inexpensive materials and organic nonlinear optical materials having advantages such as manufacturing cost, high mass productivity, and the like, and active research and development for practical application has been conducted.

  The second-order nonlinear optical effect is indispensable in principle that the system does not have a center of symmetry, and a system (crystal system) in which an organic compound having nonlinear optical activity is crystallized into a crystal structure having no center of symmetry. And a system (polymer system) in which an organic compound having nonlinear optical activity is contained or bonded to a polymer binder and the nonlinear optically active organic compound is oriented by some means. Crystalline organic nonlinear optical materials are known to exhibit very high nonlinear optical performance, but artificial control of the crystal structure is impossible at present, and a crystal structure without a symmetrical center can be obtained. This is rare, and even if it is obtained, it is difficult to produce a large organic crystal necessary for device formation. Further, the strength of the organic crystal is very brittle, and there is a problem that it is damaged in the element forming process. On the other hand, polymer-based organic nonlinear optical materials are provided with favorable properties such as film formability and mechanical strength that are useful for elementization due to the binder polymer, and have high potential for practical use. Promising.

  In the polymer organic nonlinear optical material, it is required that the nonlinear optically active organic compound is uniformly dispersed or bonded in the polymer binder without agglomeration and becomes optically homogeneous and transparent. Furthermore, as described above, in order to develop the second-order nonlinear optical effect, the nonlinear optically active organic compound must be oriented by some means to impart anisotropy, and when used for a functional element. The orientation state must be maintained stably over a long period of time in a temperature and humidity environment where the element is placed.

  Therefore, the nonlinear optically active organic compound used for the polymer organic nonlinear optical material is required to have low cohesiveness and excellent compatibility with the binder polymer in addition to high nonlinear optical performance. In addition, since the polymer organic nonlinear optical material is generally formed into an element in the form of a thin film, and the wet coating method is suitably used as a method for forming the thin film, the nonlinear optical active organic material used for the polymer organic nonlinear optical material is used. The compound is required to have high solubility in a coating solvent. On the other hand, the binder polymer is required to have a high glass transition temperature in order to stably maintain the orientation state of the encapsulating nonlinear optically active organic compound in addition to high film formability and mechanical strength.

  In order to generate secondary nonlinear optical activity in a polymer organic nonlinear optical material, it is necessary to orient the nonlinear optically active organic compound as described above. As the alignment method, an electric field poling method is generally used. The electric field poling method is an alignment method in which an electric field is applied to a nonlinear optical material, and the nonlinear optically active compound is aligned in the applied electric field direction by the Coulomb force between the dipole moment of the nonlinear optically active compound and the applied electric field. In addition to the application, the molecular motion of the nonlinear optically active compound is promoted by heating to a temperature near the glass transition temperature.

  As the nonlinear optically active organic compound, a so-called push-pull type π-conjugated compound having an electron-donating group at one end of the π-conjugated chain and an electron-withdrawing group at the other end is known to be effective. It has been. For example, DR1 having an N-ethyl-N- (2-hydroxyethyl) amino group as an electron donating group at the 4-position of a diazobenzene structure as a π-conjugated chain and a nitro group as an electron-withdrawing group at the 4 ′ position ( Disperse Red 1) is well known as a representative nonlinear optically active organic compound. However, DR1 has low compatibility with ordinary polymer binders, is easily sublimated, disappears with heating during drying or electric field poling, dialkylamino groups are oxidized and deteriorated, and nonlinear optical performance is low. There are problems such as. In order to solve these problems, various nonlinear optically active organic compounds have been developed so far, but no compound that satisfies all of them has been found yet. In particular, it is difficult to achieve both high nonlinear optical performance and high binder compatibility. That is, in a push-pull type π-conjugated compound, in general, nonlinear optics can be obtained by elongating the π-conjugated chain, strengthening the electron-withdrawing ability of the electron-withdrawing group, and strengthening the electron-donating ability of the electron-donating group. Although it is known that the performance is improved, these are accompanied by an increase in cohesiveness and a decrease in compatibility with the polymer binder.

  Moreover, the compound of the following structure is disclosed as a compound which shows very high nonlinear optical performance (for example, refer nonpatent literature 1). However, although the nonlinear optical performance is excellent, it is very difficult to obtain a film in which the cohesiveness is very high and the crystal is prevented from being precipitated and the molecules are dispersed in the polymer binder. Moreover, it is known that it is necessary to use a halogen-based solvent having a low boiling point as a coating solvent, and a halogen-based solvent is not preferable for practical use because it has a great adverse effect on the atmospheric environment.

  On the other hand, polymethylmethacrylate (PMMA) has been most studied as the binder polymer, but the glass transition temperature of PMMA is as low as about 100 ° C., and polymer organic nonlinear optics using PMMA as the binder polymer. It is known that the orientation state of the material is gradually relaxed even at room temperature, and the nonlinear optical performance is remarkably deteriorated with time, and cannot be put into practical use as a functional element (for example, see Non-Patent Document 2). In order to solve this problem, a search for a binder polymer instead of PMMA has been actively conducted, and a glass transition temperature higher than that of PMMA such as polycarbonate, polyimide, polysulfone (for example, see Patent Document 1), polycyclic olefin, and the like is high. The effectiveness of the molecule has been reported. However, when these binder polymers having a high glass transition temperature are used, the heating temperature required for electric field poling also increases, and in the case of the nonlinear optically active organic compound such as DR1, it may disappear due to sublimation. There was a problem of being oxidized. In addition, the compatibility between the binder polymer having a high glass transition temperature and the nonlinear optically active organic compound such as DR1 is not always good, and when the nonlinear optically active organic compound is added at a high concentration in order to enhance the nonlinear optical performance, they Have a problem that they are agglomerated or crystallized, and even at low concentrations, agglomeration or crystallization occurs due to heating or aging.

As described above, the problem of coexistence of high functionality (nonlinear optical performance in nonlinear optical materials) and high compatibility in polymer organic nonlinear optical materials generally includes functional organic compounds in polymer binders. This is a problem common to organic functional materials.
Chemistry of Materials, 2001, Vol. 13, p. 3043-3050. Chemical Reviews, 1994, Vol. 94, No. 1, pp. 31-75 JP-A-6-202177

  The object of the present invention is to solve the problems of the prior art as described above. That is, an object of the present invention is to maintain a high functional performance, as well as a compound having excellent heat resistance and stability, an organic functional material having high functional performance and excellent stability, and the organic functional properties. An object of the present invention is to provide an organic functional element using a material.

As a result of earnest studies on the functional organic compound and the binder polymer in order to solve the above-mentioned problems, the present inventors can solve the above-mentioned problems by utilizing a novel functional organic compound. As a result, the present invention has been completed.
That is, the said subject is solved by the following this invention.
<1> A compound represented by the following general formula (1).

(In the general formula (1), the Z ^1, Z ² and Z ³ are aromatic groups, L is a divalent π conjugated group or a single bond, Y ¹ represents a divalent organic group. In addition, Z ¹ , Z ² and Z ³ , and the divalent π-conjugated group represented by L may be combined with each other to form a condensed ring.

  <2> The compound according to <1>, which is represented by the following general formula (2).

(In the general formula (2), Z ¹ , Z ² and Z ³ are aromatic groups, L is a divalent π-conjugated group or single bond, Y ² is a divalent organic group or single bond, R ¹ And R ² represents an organic group, and n and m each represents an integer of 0 to 3. In addition, an aromatic group represented by Z ¹ , Z ² and Z ³ , and a divalent group represented by L Any two or more of the π-conjugated groups may be bonded to form a condensed ring, and the organic groups represented by R ¹ and R ² are R ¹ and R ² , R ¹ or R ² , It may combine to form a ring structure.)

  <3> An organic functional material comprising the compound according to <1> or <2> as the organic functional compound.

  <4> The organic functional material according to <3>, wherein the organic functional compound is dispersed or bonded to a polymer binder.

  <5> The organic functional material according to <4>, wherein the polymer binder is one or more selected from polyimide, polycarbonate, polyarylate, and polycyclic olefin.

  <6> An organic functional element, wherein the organic functional material according to any one of <3> to <5> is applied.

  <7> The organic functional element according to <6>, which operates by a nonlinear optical function.

  According to the present invention, while maintaining high functional performance, a compound having excellent heat resistance and stability, an organic functional material having high stability while maintaining high functional performance, and the organic functional material The used organic functional element can be provided.

<Organic functional compound>
The compound of the present invention is represented by the following general formula (1).
The compound is an organic functional compound having high functional performance. The functional performance includes a photoelectric function such as an ambipolar charge transport function and a photocharge generation function; a light emitting function such as a photoluminescence function and an electroluminescence function; Non-linear optical functions such as a generating function, an electro-optical function, and a photorefractive function;

(In the general formula (1), the Z ^1, Z ² and Z ³ are aromatic groups, L is a divalent π conjugated group or a single bond, Y ¹ represents a divalent organic group. In addition, Z ¹ , Z ² and Z ³ , and the divalent π-conjugated group represented by L may be combined with each other to form a condensed ring.

It is known that an organic functional compound having a substituted or unsubstituted triarylamine structure, which is a kind of electron donating group, has higher thermal stability than an organic functional material having a corresponding dialkylamine structure. (The details are described in "American Chemical Society Journal," 1993, 115, 12599-12600.) Moreover, the 3,5,3 ′, 5′-tetraalkyldiphenoquinone derivative electron-withdrawing compound having the same structure as the electron-withdrawing group of the compound represented by the general formula (1) has strong electron-withdrawing property. It is known that it has high binder compatibility and functions as an excellent electron transport material by being dispersed in a polymer binder (for details, see “Chemistry of Materials”, 1991, Vol. 3, pages 709-714. It is described in).
The inventors have shown that the strong electron withdrawing property and high binder compatibility of 4-cyano-5-dicyanovinylidenyl-2,5-dihydrofuran-3-yl group derivatives, and the high thermal stability of triarylamine derivatives. By using them as electron-withdrawing groups and electron-donating groups of push-pull type π-conjugated compounds, heat resistance, oxidation resistance, light resistance, sublimation resistance, solubility, and ease of synthesis In view of the above, it has been found that the compound exhibits a preferable function and is suitably used as an organic functional material.

Here, the compound represented by the general formula (1) will be described.
In the general formula (1), Z ¹ and Z ² are monovalent and Z ³ is a divalent aromatic group. The aromatic group is not particularly limited, but is preferably a 5- to 7-membered ring, more preferably a 6-membered ring, which may contain heteroatoms such as nitrogen, oxygen, sulfur, etc. The aromatic ring may have a condensed structure. Further, Z ¹ , Z ² and Z ³ may be bonded directly or via an appropriate linking group.
The aromatic group may have a substituent, and Z ¹ and Z ² preferably have a bulky substituent rather than a methyl group. Examples of the substituent include an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an n-hexyl group, a 2-ethylhexyl group, a cyclohexyl group, a phenyl group, an adamantyl group, a methoxy group, and a phenoxy group. Can be mentioned.

  Specific examples of the monovalent (substituted) aromatic group include, for example, phenyl group, 1-naphthyl group, 2-naphthyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, thiophen-2-yl Yl group, thiophen-3-yl group, azulene-1-yl group, pyrrol-2-yl group, pyrrol-3-yl group, etc., among which phenyl group, 1-naphthyl group, 2-naphthyl group, thiophene -2-yl group and thiophen-3-yl group are preferable, and phenyl group and thiophen-2-yl group are preferable from the viewpoint of being easy to synthesize and having high electron density and high stability.

  Specific examples of the divalent (substituted) aromatic group include, for example, 1,4-phenylene group, 1,3-naphthalenyl group, 1,4-naphthalenyl group, 2,6-naphthalenyl group, 2, Examples include 7-naphthalenyl group, 2,5-thienyl group, 2,5-pyridinyl group, 2,5-pyrimidyl group, 9,10-anthracenyl group, and the like. Among them, 1,4-phenylene group, 1,4- A naphthalenyl group and a 2,5-thienyl group are preferable, and an unsubstituted 1,4-phenylene group, substituted or 3, 4 is particularly preferable from the viewpoint of easy synthesis and an atomic group having high electron density and high stability. A 2,5-thienyl group having a substituent at the position is preferred.

In addition, any of two or more of the aromatic groups represented by Z ¹ , Z ² and Z ³ may be bonded to form a condensed ring. Examples of the condensed ring include Z ¹ and Z ² which are nitrogen atoms. Examples thereof include those that are bonded to an atom at an ortho position to form a carbazole structure.

In the general formula (1), L is a divalent π-conjugated group or a single bond. Further, it may be bonded to any one of Z ¹ , Z ² and Z ³ directly or via an appropriate linking group to form a condensed ring.
The π-conjugated group is preferably a π-conjugated group that is included in the ring structure, directly linked to the ring structure, or adjacent to the ring structure, and more preferably a trans-vinylene structure, trans-vinylene-p-phenylene- a trans-vinylene structure, an ethynyl structure having an acetylene bond, an ethynyl-p-phenylene-ethynyl structure, a trans-azo-structure, a trans-azo-p-phenylene-trans-azo structure, or a structure obtained by accumulating these structures More preferred. It should be noted that by adjusting the length of L, functional performance such as nonlinear optical performance can be further improved. In general, the longer L is, the greater the functional performance. On the other hand, when L becomes longer, solubility and compatibility are lowered, and workability is impaired. In addition, the economics resulting from the ease of synthesis are greatly reduced as L becomes longer. There is no primary correlation with the length of L in terms of heat resistance and durability, but it decreases when L is extremely long. From this viewpoint, L is particularly preferably a trans-vinylene structure or a trans-vinylene-p-phenylene-trans-vinylene structure.

In the general formula (1), Y ¹ is a divalent organic group. The ring structure formed including Y ¹ is not particularly limited, but is preferably a 5- or 6-membered ring, and the ring structure may contain a heteroatom. Examples of the heteroatom include —NH—, —O—, —S—, —S (═O) ₂ —, —SO—, —PO ₂ —, and the like. Among them, —NH—, —O—, -S- is preferred. Furthermore, the ring structure formed including Y ¹ may be in the form of a condensed ring in which a ring is further condensed.

  In addition, as the organic functional compound in the present invention, among the compounds represented by the general formula (1), a compound represented by the following general formula (2) is easy to synthesize, has heat resistance, and a phase with a binder. From the viewpoint of excellent solubility, it is more preferably used.

(In the general formula (2), Z ¹ , Z ² and Z ³ are aromatic groups, L is a divalent π-conjugated group or single bond, Y ² is a divalent organic group or single bond, R ¹ And R ² represents an organic group, and n and m each represents an integer of 0 to 3. In addition, an aromatic group represented by Z ¹ , Z ² and Z ³ , and a divalent group represented by L Any two or more of the π-conjugated groups may be bonded to form a condensed ring, and the organic groups represented by R ¹ and R ² are R ¹ and R ² , R ¹ or R ² , It may combine to form a ring structure.)

In general formula (2), Z ¹ , Z ² , Z ³ and L are the same as in general formula (1).

In general formula (2), R ¹ and R ² are organic groups, and are particularly preferably aliphatic substituents. When n or m is 2 or more, the plurality of R ¹ or the plurality of R ² may be the same or different from each other. Furthermore, R ¹ and R ² , R ¹ or R ² may be bonded to each other to form a ring structure. n and m represent the number of groups bonded to the same ring and represent a number of 0 to 3.

Examples of the fatty attribute substituent include substituted or unsubstituted alkyl groups, alkyloxy groups, alkylthio groups, alkenyl groups, alkynyl groups, substituted or unsubstituted amino groups, acryloyloxy groups, methacryloyloxy groups, and the like. .
The alkyl group, alkyloxy group, alkylthio group, alkenyl group, alkynyl group, and substituted or unsubstituted amino group may be linear or branched, and are not particularly limited. Although it does not exist, it is preferable that carbon number is 1-18, Furthermore, it is 1-8.

R ¹ and R ² , R ¹ or R ² may be bonded to each other to form a ring structure.
In the general formula (2), n and m are each preferably 0 to 1, since the raw material synthesis reaction may not proceed easily due to steric hindrance in the case of a polysubstituted product.

In the general formula (2), Y ² is a divalent organic group or a single bond. The ring structure formed including Y ² is not particularly limited, but is preferably a 5- or 6-membered ring.
Examples of the divalent organic group include —CH ₂ —, —NH—, —O—, —S—, —S (═O) ₂ —, —SO—, —PO ₂ — and the like. CH ₂ —, —NH—, —O—, and —S— are preferred.

  Specific examples of the compounds represented by the general formula (1) and the general formula (2) include the following. In addition, the following structural formula is shown in a plane for simplification and in one case with respect to structural isomerism, and ignored with respect to optical isomers, but actually has a three-dimensional structure, and Any possible structure may be used for structural isomerism, optical isomers, and combinations thereof.

In the general formula (1), all or any of Z ¹ to Z ³ is an aromatic ring containing a hetero atom (eg, pyridine ring, thiophene ring) or condensed ring (eg, naphthalene ring, pyrene ring). Suitable examples include those in which Z ¹ and Z ² are condensed to form a carbazole structure or a xanthene structure.

  As a method for synthesizing the compounds represented by the general formulas (1) and (2), any arbitrary method can be used. For example, in the case where the L part is a single double bond, for this formation, a compound having a methyl group adjacent to a corresponding formyl compound and a corresponding electron-withdrawing group as shown below is subjected to dehydration condensation in the presence of a base. This method is useful. As a method for synthesizing the corresponding formyl compound, a formylation method such as the Vilsmeier method can be used. As a method for synthesizing a compound having a methyl group adjacent to the corresponding electron-withdrawing group, the method described in the above-mentioned “Chemistry of Materials”, 1991, Vol. 3, pages 709 to 714; US Pat. Available.

As the formation reaction of the triarylamine moiety, known reactions such as Ulmann coupling, Suzuki reaction, Heck reaction, and Witig reaction can be used.
The formation of the dihydrofuranyl moiety can be synthesized, for example, by the method disclosed in “Chemistry of Materials”, 2002, Vol. 14, pages 2393-2400, or the method described in the references described therein.

  In the organic functional material of the present invention to be described later, the content of the organic functional compound varies depending on the type of the organic functional compound used, the required functional performance, mechanical strength, etc. In particular, when used as an organic nonlinear optical material, the proportion of the total mass is preferably in the range of 1 to 90% by mass. The reason is that if the amount is less than 1% by mass, sufficient functional performance cannot be obtained in many cases. If the amount exceeds 90% by mass, problems such as insufficient mechanical strength tend to occur. is there. A more preferable range of the content of the organic functional compound is 10 to 75% by mass, and further preferably 25 to 60% by mass.

<Organic functional materials>
The organic functional material of the present invention contains the compound represented by the general formula (1) as an organic functional compound. The organic functional material of the present invention has not only high functional performance but also high heat resistance and stability of the compound itself represented by the general formula (1) used as the organic functional compound, and the general formula (1 The compound represented by) has high compatibility with the polymer binder and can form a homogeneous film, and thus has excellent stability such as heat resistance and stability over time.
(Binder polymer)
The organic functional material of the present invention is characterized by containing the organic functional compound, and may be used as a single crystal, a polycrystal, or an amorphous solid of the organic functional compound alone. It is preferable to use as a composite material in which an organic functional compound is dispersed or bonded to a polymer binder in view of demands for film formability and mechanical strength.

  The binder polymer used in the present invention may be any polymer as long as it is excellent in optical quality and film formability, but preferably has a glass transition temperature of 100 ° C. or higher. Particularly preferred are those having a glass transition temperature of 140 ° C. or higher and high mechanical strength, and specific examples include polyimide, polycarbonate, polyarylate, and polycyclic olefin. Among these, polycarbonate and polyarylate are particularly preferred. preferable. The functional organic compound represented by the general formula (1) exhibits high compatibility with these polymer binders.

  The above-mentioned organic functional compound is provided as an organic functional material in a microcrystalline state or a molecular state dispersed in a binder polymer, but when applied to a device that utilizes light-related functions, the molecular state It is preferable from the viewpoint of optical quality such as transparency. Further, the above organic functional compound may be chemically linked into the side chain or main chain of the binder polymer.

(Other additives)
In addition to the organic functional compound and the binder polymer, various additives can be added to the organic functional material of the present invention as necessary. For example, a known antioxidant such as 2,6-di-t-butyl-4-methylphenol and hydroquinone is used for the purpose of suppressing the oxidative deterioration of the organic functional compound and / or the binder polymer. For the purpose of suppressing UV degradation of the binder polymer, a known UV absorber such as 2,4-dihydroxybenzophenone or 2-hydroxy-4-methoxybenzophenone is used. In the case of using a known leveling agent such as silicone oil for the purpose of improving the surface smoothness of the coating film, or an organic functional compound and / or binder polymer having a crosslinking curable functional group, For the purpose of promoting curing, a known curing catalyst or curing aid may be added.

(Thin film formation method)
The form of the organic functional material of the present invention may be any form, but it is generally used in the form of a thin film for application to a nonlinear optical element. As a method for producing a thin film containing the organic functional material of the present invention, known methods such as an injection molding method, a press molding method, a soft lithography method, a wet coating method, etc. can be used. From the viewpoint of mass productivity, film quality (thickness uniformity, few defects such as bubbles), etc., spin-coat a solution in which at least the above organic functional material and binder polymer are dissolved in an organic solvent A wet coating method in which a film is formed by coating on a suitable substrate by a method such as a method, a blade coating method, a dip coating method, an ink jet method, or a spray method is preferred.

  The organic solvent used in the wet coating method may be any organic solvent as long as it can dissolve the organic functional compound to be used and the binder polymer, but preferably has a boiling point in the range of 100 to 200 ° C. When an organic solvent having a boiling point of less than 100 ° C. is used, solvent volatilization occurs when the coating solution is stored, and the viscosity of the coating solution changes (increases). There is a tendency for such problems to become prominent. On the other hand, when an organic solvent having a boiling point exceeding 200 ° C. is used, it is difficult to remove the solvent after coating, and the remaining organic solvent acts as a plasticizer for the polymer binder and causes a decrease in the glass transition temperature. There is a case. Examples of preferred organic solvents include diethylene glycol dimethyl ether, cyclopentanone, cyclohexanone, cyclohexanol, toluene, chlorobenzene, xylene, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, and the like. These organic solvents may be used alone or in combination. A mixed solvent obtained by adding an organic solvent such as tetrahydrofuran, methyltetrahydrofuran, dioxane, methyl ethyl ketone, or isopropanol having a boiling point of less than 100 ° C. to these preferable organic solvents can also be used.

(Orientation method)
In order to generate secondary nonlinear optical activity in a polymer organic nonlinear optical material, it is necessary to orient the nonlinear optically active organic compound as described above. As the alignment method, a polymer organic nonlinear optical material is applied on a substrate having an alignment film on the surface, and the nonlinear optically active organic compound in the polymer organic nonlinear optical material is obtained by the orientation of the substrate alignment film. There is a method for inducing the orientation. Also, known polling methods such as an optical poling method, an optically assisted electric field poling method, and an electric field poling method can be used effectively. Among these, the electric field poling method is particularly preferable in terms of the simplicity of the apparatus and the high degree of orientation obtained.

  The electric field poling method is roughly divided into a contact poling method in which a nonlinear optical material is sandwiched between a pair of electrodes and an electric field is applied, and a corona poling method in which a surface of the nonlinear optical material on the substrate electrode is subjected to corona discharge and a charging electric field is applied. The The electric field poling method is an alignment method in which the nonlinear optically active compound is aligned in the applied electric field direction by the Coulomb force between the dipole moment of the nonlinear optically active compound and the applied electric field. In the electric field poling method, generally, by applying an electric field and heating to a temperature in the vicinity of the glass transition temperature of the nonlinear optical material, the alignment movement in the electric field direction of the nonlinear optically active compound is promoted and sufficient alignment is achieved. After the induction, the applied electric field is removed after cooling to room temperature with the electric field applied and freezing the alignment state. However, since this orientation state is basically a thermodynamic nonequilibrium state, even if the temperature is lower than the glass transition temperature, it is gradually randomized over time, and the fundamental problem is that nonlinear optical performance deteriorates. Have Randomization of the orientation state over time progresses more gradually as the difference between the environmental temperature where the nonlinear optical material is placed and the glass transition temperature is larger. Therefore, in actual use, the binder resin having a higher glass transition temperature is used. This problem can be solved.

<Organic functional element>
The organic functional element of the present invention is characterized by utilizing the function of the organic functional material of the present invention. Specific examples thereof include an organic electrophotographic photosensitive member utilizing a charge transport function and / or a charge generation function. Electroluminescent element utilizing charge transport function and / or electroluminescence function; laser element or optical amplification element utilizing photoluminescence function; utilizing nonlinear optical function such as harmonic generation function, electro-optic function, photorefractive function, etc. Nonlinear optical elements and the like can be mentioned. Since the organic functional material of the present invention has particularly excellent nonlinear optical performance, the organic functional element of the present invention is particularly an organic nonlinear optical element using the organic functional material of the present invention having a nonlinear optical function. preferable.

  The organic nonlinear optical element may be any element that operates based on the nonlinear optical effect. Specific examples thereof include a harmonic generation element, a wavelength conversion element, a photorefractive element, an electro-optic element, and the like. Can be mentioned. Particularly preferable are electro-optical elements such as an optical switch, an optical modulator, and a phase shifter that operate based on the electro-optical element effect.

  The electro-optic element is preferably used as an element in which a nonlinear optical material is formed on a substrate in a waveguide structure and sandwiched between electrode pairs for input electric signals.

  As a material constituting such a substrate, metals such as aluminum, gold, iron, nickel, chromium, and titanium; semiconductors such as silicon, gallium-arsenic, indium-phosphorus, titanium oxide, and zinc oxide; ceramics such as glass; Plastics such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polysulfone, polyether ketone, polyimide, and the like can be used.

  A conductive film may be formed on the surface of these substrate materials. Examples of the material of the conductive film include metals such as aluminum, gold, nickel, chromium, and titanium; tin oxide, indium oxide, ITO ( Conductive oxides such as tin oxide-indium oxide composite oxide); conductive polymers such as polythiophene, polyaniline, polyparaphenylene vinylene, and polyacetylene. These conductive films are formed by using known dry film forming methods such as vapor deposition and sputtering, and known wet film forming methods such as spray coating method, dip coating method, and electrolytic deposition method. A pattern may be formed. Note that the conductive substrate or the conductive film formed on the substrate as described above is used as an electrode at the time of polling or operation as an element (hereinafter also referred to as “lower electrode”).

  On the substrate, if necessary, an adhesive layer for improving the adhesion between the film formed on the substrate and the substrate, a leveling layer for smoothing irregularities on the substrate surface, or these functions are provided. Some intermediate layer provided in a lump may be formed. The material for forming such a film is not particularly limited, and examples thereof include acrylic resins, methacrylic resins, amide resins, vinyl chloride resins, vinyl acetate resins, phenol resins, urethane resins, vinyl alcohol resins, acetal resins, and the like. A known product such as a crosslinked product of a zirconium chelate compound, a titanium chelate compound, a silane coupling agent, and the like, or a co-crosslinked product thereof can be used.

  The electro-optical element of the present invention is preferably formed to include a waveguide structure, and the nonlinear optical material of the present invention is particularly preferably included in the core layer of the waveguide.

A clad layer (hereinafter also referred to as “lower clad layer”) may be formed between the core layer containing the nonlinear optical material of the present invention and the substrate. The lower cladding layer may be any layer as long as it has a lower refractive index than the core layer and is not affected by the formation of the core layer. As such materials, UV curable or thermosetting resins such as acrylic, epoxy, and silicone; polyimide; SiO _{2 and the} like are preferably used.

After forming the core layer of the nonlinear optical material of the present invention, a clad layer (hereinafter sometimes referred to as “upper clad layer”) may be further formed on the upper layer in the same manner as the lower clad layer. As a result, a slab waveguide having a structure of substrate / lower cladding layer / core layer / upper cladding layer is formed.
After the core layer is formed, the core layer is patterned by a known method using a semiconductor process technology such as reactive ion etching (RIE), photolithography, electron beam lithography, and the like, and a channel type waveguide or a ridge type waveguide Can also be formed. Alternatively, a channel type or a ridge type waveguide can be formed by changing the refractive index of the irradiated portion by patterning and irradiating a part of the core layer with UV light, an electron beam or the like.

A basic electro-optic element is formed by forming an electrode (hereinafter sometimes referred to as an “upper electrode”) for applying an input electric signal to the surface of the upper cladding layer in a desired region of the upper cladding layer. can do.
When forming a channel-type waveguide or a ridge-type waveguide as described above, the core layer pattern may be a known device structure such as a linear type, a Y-branch type, a directional coupler type, or a Mach-Zender type. It can be configured, and can be applied to known optical information communication devices such as an optical switch, an optical modulator, and a phase shifter.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In the examples, “part” represents “part by mass” unless otherwise specified.

Example 1
-Production of organic functional compounds-
The following compound (A) was produced by the following method.
To a flask equipped with a stirrer and a condenser, p- [N, N-di (3-methoxyphenyl) amino] -benzaldehyde (2.85 g, 0.01 mol), 1-oxa-2-dicyanobenzylidene-3-cyano Take 3.21 g of -4-methyl-6,8-dibenzo-spiro- [4,4] -nonane-3-ene and add 40 ml of ethanol in which 5 mg of sodium hydroxide is dissolved in advance to 10 ml. Heated to reflux for hours. Next, ethanol was distilled off, and the resulting solid was purified with a silica gel column using a mixed solvent of n-hexane / ethyl acetate (2: 1 by mixing ratio) to obtain 3.5 g of the desired product. It was. The yield was 59%. This reaction scheme is shown below.

In addition, the data which identified the obtained compound (A) by the NMR spectrum are shown in FIG.
(Δ = 5.58-7.77: m, 23.2H (theoretical value 22.0H), δ = 3.71: s, 6.0H (theoretical value 6.0H))

-Evaluation as a nonlinear optical material-
Poly [Bisphenol A carbonate- which is a kind of polycarbonate (binder polymer) and 3 parts of the compound (A) on a glass substrate having a pair of gold parallel electrodes (distance between electrodes = 20 μm) on the surface. co-4,4 ′-(3,3,5-trimethylcyclohexylidene) diphenol carbonate] (manufactured by Aldrich, glass transition temperature 200 ° C.) and 7 parts of tetrahydrofuran (boiling point 66 ° C.) dissolved in 90 parts by spin coating It was applied by the method and dried at room temperature for 3 hours and at 100 ° C. for 3 hours to obtain a thin film having a thickness of 0.1 μm.

Next, with the electric field of 50 V / μm applied between the electrodes, the thin film was held at 170 ° C. for 15 minutes, and from that state, the electric field was applied to cool to room temperature to remove the electric field, and electric field poling was performed. .
When the semiconductor laser light having an oscillation wavelength of 1550 nm is irradiated on the thin film made of the organic nonlinear optical material of the present invention subjected to electric field poling in this way, generation of the second harmonic of 775 nm can be observed, and the nonlinear optical material As a result, it was confirmed that it functions effectively. Furthermore, when the nonlinear optical material was held in a high temperature environment of 65 ° C. for 10 days and then irradiated again with laser light, the generation of second harmonics having the same intensity as before holding could be confirmed, and the nonlinear optical material was It was confirmed that it has high heat resistance and stability over time.
In addition, when this thin film was observed with the optical microscope, the segregation etc. of the compound (A) were not recognized, but it has confirmed that the compound (A) was a clear film | membrane uniformly disperse | distributed in a polycarbonate.

(Comparative Example 1)
Except that the nonlinear optically active organic compound (compound (A)) in Example 1 was changed to the following compound (B) described in “Chemistry of Materials, 2001, Vol. 13, pages 3043-3050”, Example When a thin film of an organic nonlinear optical material was produced in the same manner as in No. 1, fine crystals of the following compound (B) were precipitated, and a clear film could not be obtained.

(Comparative Example 2)
As described in “Chemistry of Materials, 2001, Vol. 13, p. 3043-3050”, in Comparative Example 1, 1,2-dichloroethane was used instead of tetrahydrofuran as the coating solvent, and great care was taken. As a result of spin coating, a clear film was obtained.
When this film was subjected to electric field poling treatment in the same manner as in Example 1 and irradiated with laser light in the same manner as in Example 1, it was possible to observe the generation of second harmonics that were slightly stronger than in Example 1. It was. Further, as in Example 1, after being kept in a high temperature environment for 10 days and then irradiated again with laser light, green light emission due to the generation of the second harmonic was observed, but the material became non-uniform, segregated, etc. It was recognized that the scattering of the emitted light was large and the emission pattern was clearly different from the initial one.

  By comparing Example 1 with Comparative Examples 1 and 2, according to the present invention, it has been confirmed that the present invention exhibits high nonlinear optical performance “Chemistry of Materials, 2001, Vol. 13, pages 3043-3050”. A non-halogen organic solvent having a boiling point of 100 ° C. or higher as a coating solvent can be easily obtained without paying special attention. Was confirmed. In addition, regarding heat resistance and stability over time, the material of the comparative example is disturbed in the light emission pattern due to change over time, and further, the reproducibility is also reduced by heating, so the material of the present invention is a comparative example. It was confirmed that it was superior to the listed materials.

(Example 2)
-Production of organic functional compounds-
The following compound (C) was produced by the following method.
As a spiro compound, instead of 1-oxa-2-dicyanobenzylidene-3-cyano-4-methyl-6,8-dibenzo-spiro [4,4] -nonan-3-ene, 1,8-dioxa-2 Compound C was synthesized in the same manner as in Example 1 except that 3.37 g of -dicyanobenzylidene-3-cyano-4-methyl-6,9-dibenzo-spiro- [4,5] -decan-3-ene was used. did. Yield was 3.3 g (54% yield).
The obtained compound (C) was identified by NMR spectrum. (Δ = 5.55-7.77: m, 22.8H (theoretical value 22.0H), δ = 3.71: s, 6.0H (theoretical value 6.0H)).

-Evaluation as a nonlinear optical material-
In Example 1, the nonlinear optically active organic compound (compound (A)) is the compound (C), and the binder polymer is a polycyclic olefin (D) having the following structural formula (trade name Arton, manufactured by JSR, glass transition temperature 170). The organic nonlinear optical material thin film subjected to electric field poling was prepared in the same manner as in Example 1 except that the heating temperature during electric field poling was changed to 140 ° C.
When the obtained thin film was irradiated with laser in the same manner as in Example 1, generation of second harmonics having the same intensity as in Example 1 was observed, and it was confirmed that the thin film effectively functions as a nonlinear optical material. Moreover, even after holding in a high temperature environment for 10 days, generation of second harmonics having the same strength as before holding was confirmed, and it was confirmed that the nonlinear optical material had high heat resistance and stability over time.

(Example 3)
On a glass substrate (2 cm × 2 cm) on which a gold thin film as a lower electrode was formed on the surface, a UV curable acrylic resin (Norland, product name: NOA72) was applied by a spin coating method, and 100 mW / After irradiating with cm ² ultraviolet light (USHIO INC., high pressure mercury lamp) for 30 seconds, a heat treatment at 120 ° C. for 30 minutes was performed to form a thin film with a thickness of 2 μm to form a lower cladding layer.

Next, a cyclopentanone solution containing 2 parts of the nonlinear optically active organic compound (compound (C)) used in Example 2 and 8 parts of the polycyclic olefin (D) is spin-coated on the lower cladding layer. It was applied and dried at 120 ° C. for 1 hour to form a thin film having a thickness of 2 μm to form a core layer.
Next, the same UV curable acrylic resin as that of the lower cladding layer was formed on the core layer in the same manner as the lower cladding layer to form an upper cladding layer (film thickness: 2 μm).

Next, a striped gold thin film (stripe width 20 μm, stripe interval 30 μm) was formed as an upper electrode on the upper clad layer by using a normal photolithography method and a sputtering method.
The sample obtained as described above was cut into a chip having a width of 5 mm by a dicer (manufactured by Disco), the cut surface was polished with sandpaper, and a slab waveguide element (electrical) having the configuration shown in FIG. An optical element) was produced.

Next, an electric field poling process was performed under the same conditions as in Example 1 by applying an electric field of 150 V / μm between the upper electrode and the lower electrode of this element.
In order to confirm that the element subjected to the electric field polling function functions as an electro-optic element, the electro-optic is performed according to the method described in “Japanese Journal of Applied Physics, 1991, Vol. 30, No. 2, pages 320 to 326”. The characteristics were evaluated. FIG. 3 shows a schematic configuration diagram of the evaluation system. Laser light (oscillation wavelength 850 nm) emitted from the light source (semiconductor laser) 21 through the half-wave plate 22 passes through the polarizer 23a, and enters the element 28 from one end face through the lens 24. The incident laser light propagates through the core layer in the element 28, exits from the other end face, passes through the polarizer 23 b through the lens 24 and the pin pole 26, and is then detected by the photodetector 27.
When an electric field was applied between the upper and lower electrodes of this element 28 and the electric field intensity was changed from 0 V to 5 V, it was confirmed that the detected light intensity decreased as the electric field intensity increased. This is due to the fact that this element has an electro-optic effect, and the polarization plane is rotated in response to the application of an electric field, and this element functions effectively as an electro-optic element and can be used as an optical modulator. Is. Furthermore, after the element 28 was held in a high temperature and high humidity environment of 65 ° C. and 85% for 10 days, the same electro-optical characteristics were evaluated again. As a result, the same light modulation characteristics as before the holding could be confirmed. Was confirmed to have high heat resistance and stability over time.

(Comparative Example 3)
An electro-optic element was produced in the same manner as in Example 3 except that the nonlinear optically active organic compound (Compound (C)) in Example 3 was changed to Disperse Red 1 (manufactured by Across Organics). When the electro-optical characteristics were evaluated, the light modulation amount when the applied electric field intensity was changed from 0 V to 5 V was very low, one tenth or less of the light modulation amount in Example 3. Furthermore, in the evaluation after being held for 10 days in a high temperature and high humidity environment of 65 ° C. and 85%, precipitation of Disperse Red 1 crystals was observed, and it could not be used as an electro-optical element.

  By comparing Example 3 and Comparative Example 3, it is confirmed that the present invention provides an electro-optical element having both excellent electro-optical characteristics and excellent stability (heat resistance, stability over time). did it.

  As described above, the organic functional material of the present invention is characterized by using an organic functional compound having a specific structure excellent in functional performance such as nonlinear optical function, amorphous property, heat resistance, sublimation resistance, etc. Good compatibility with polymer binders with glass transition temperature, organic functional compounds do not agglomerate even at high concentrations and take a uniform dispersed state, so both high optical quality and excellent functional performance, and non-linear optical materials Has a favorable effect such that the heat resistance and the temporal stability of the alignment state are high, and excellent performance can be maintained over a long period of time. For this reason, by using the organic functional material of the present invention, an organic functional element excellent in various characteristics and stability as the organic functional material can be realized.

It is a graph which shows the identification data of the organic functional compound manufactured in the Example. FIG. 3 is a schematic cross-sectional view showing an electro-optical element manufactured in an example. It is a schematic diagram which shows the evaluation system used for evaluation of an electro-optical characteristic in an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Glass substrate 12 ... Lower electrode 13 ... Lower clad layer 14 ... Core layer 15 ... Upper clad layer 16 ... Upper electrode 21 ... Laser light source 22 ... Half wavelength Plates 23a, 23b ... Polarizer 24 ... Lens 25 ... Power supply 26 ... Pinhole 27 ... Photodetector 28 ... Electro-optic element

Claims (7)

A compound represented by the following general formula (1):

(In the general formula (1), the Z ^1, Z ² and Z ³ are aromatic groups, L is a divalent π conjugated group or a single bond, Y ¹ represents a divalent organic group. In addition, Z ¹ , Z ² and Z ³ , and the divalent π-conjugated group represented by L may be combined with each other to form a condensed ring. The compound according to claim 1, which is represented by the following general formula (2).

(In the general formula (2), Z ¹ , Z ² and Z ³ are aromatic groups, L is a divalent π-conjugated group or single bond, Y ² is a divalent organic group or single bond, R ¹ And R ² represents an organic group, and n and m each represents an integer of 0 to 3. In addition, an aromatic group represented by Z ¹ , Z ² and Z ³ , and a divalent group represented by L Any two or more of the π-conjugated groups may be bonded to form a condensed ring, and the organic groups represented by R ¹ and R ² are R ¹ and R ² , R ¹ or R ² , It may combine to form a ring structure.)   An organic functional material comprising the compound according to claim 1 or 2 as an organic functional compound.   The organic functional material according to claim 3, wherein the organic functional compound is dispersed or bonded to a polymer binder.   The organic functional material according to claim 4, wherein the polymer binder is one or more selected from polyimide, polycarbonate, polyarylate, and polycyclic olefin.   An organic functional element, wherein the organic functional material according to any one of claims 3 to 5 is applied.   The organic functional element according to claim 6, which operates by a nonlinear optical function.

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