JP2006267981A - Organic functional material and organic functional element using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic functional material having excellent functional performance such as a nonlinear optical function, polymer compatibility, heat resistance and sublimation resistance. <P>SOLUTION: The organic functional material contains a compound represented by formula (1) as an organic functional compound. In formula (1), L denotes a π-conjugated group which can have a substituent, A denotes an electron-attractive group which can have a substituent, and R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP>, R<SP>4</SP>, R<SP>5</SP>and R<SP>6</SP>denote organic groups independent of each other. In R<SP>2</SP>to R<SP>5</SP>, L and A, optional ones can be connected to each other to form a ring structure. <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, etc .; an organic electroluminescent device that can be used for an electronic display board, a display, etc .; an optical modulator useful in optical information communication, optical information processing, etc. Organic nonlinear optical elements that can be used for optical switches, optical integrated circuits, optical computers, optical memories, wavelength conversion elements, holographic elements, etc .; organic solar cells such as dye-sensitized solar cells and organic pn junction solar cells; The present invention relates to an organic functional element that exhibits a function related to light and / or electricity. Furthermore, this invention relates to the organic functional material which is a key material which forms this organic functional element.

  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. As the second-order nonlinear optical material, inorganic nonlinear optical materials such as lithium niobate and potassium dihydrogen phosphate have already been put into practical use and widely used. However, in recent years, 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 use is being conducted.

  The second-order nonlinear optical effect is indispensable in principle that there is no symmetry center in the system, and a system in which an organic compound having nonlinear optical activity is crystallized into a crystal structure without a symmetry center (referred to as a crystal system). ), And an organic compound having nonlinear optical activity contained in or bonded to a polymer binder, and the system is roughly classified into a system in which the nonlinear optically active organic compound is oriented by some means (referred to as a polymer system). Crystalline organic nonlinear optical materials are known to exhibit extremely 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. It is rare, and even if it is obtained, it is very difficult to produce a large organic crystal necessary for device formation, and the strength of the organic crystal is very brittle and breaks in the device formation step. There are problems such as. On the other hand, polymer-based organic nonlinear optical materials are provided with favorable characteristics such as film formability and mechanical strength that are useful for elementization due to the binder polymer, and have a potential for practical use. Highly promising.

In the polymer-based 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 oriented 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, an N-ethyl-N- (2-hydroxyethyl) amino group as an electron donating group at the 4-position of one end of a diazobenzene structure as a π-conjugated chain, and an electron-withdrawing group at the 4 'position of the other end Disperse Red 1 (generally abbreviated as DR1) having a nitro group as a group is well known as a representative nonlinear optically active organic compound. However, DR1 has low compatibility with ordinary polymer binders, is easily sublimated and disappears during drying or electric field poling, and the dialkylamino group is chemically unstable and oxidized and altered. Such as low nonlinear optical performance. 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, the π-conjugated chain is lengthened, the electron-withdrawing group has a stronger electron-withdrawing ability, the electron-donating group has a stronger electron-donating ability, and so on. It is known that the optical performance is improved, but these are accompanied by an increase in cohesiveness and a decrease in compatibility with the polymer binder.
For example, Non-Patent Document 1 obtains a film in which a compound having the following structure has a very high nonlinear optical performance, but has a very high cohesiveness and suppresses crystal precipitation and is molecularly dispersed in a polymer binder. It is disclosed that it is very difficult. Further, it is disclosed that it is necessary to use a halogen-based solvent having a low boiling point as a coating solvent. However, a halogen-based solvent has a great adverse effect on the air environment and is not preferable for practical use.

  On the other hand, polymethylmethacrylate (generally abbreviated as PMMA) has been most studied as the binder polymer. However, the glass transition temperature of PMMA is as low as about 100 ° C., and PMMA is used as a binder polymer. It is known that the orientation state of the molecular organic nonlinear optical material gradually relaxes even at room temperature, and the nonlinear optical performance is remarkably deteriorated with time, so that it cannot be put into practical use as a functional element (Non-patent Document 2). reference). In order to solve this problem, a search for binder polymers that replace PMMA has been actively conducted. Polycarbonate, polyimide, polysulfone (see Patent Document 1), polycyclic olefins, and other polymers having a glass transition temperature higher than those of PMMA. Although effectiveness has been reported, the use of binder polymers with these high glass transition temperatures increases the heating temperature required for electric field poling, and the loss of nonlinear optically active organic compounds such as DR1 disappears by sublimation. There was a problem of being oxidized or 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 Flocculates or crystallizes, and even at low concentrations, there is a problem that flocculation or crystallization occurs due to heating or aging.

In the above-described polymer organic nonlinear optical material, the problem of achieving both high functionality (nonlinear optical performance in nonlinear optical material) and high compatibility is generally obtained by incorporating a functional organic compound in a polymer binder. This is a problem common to organic functional materials.
Chemistry of Materials, 2001, Volume 13, pages 3043-3050 Chemical Reviews, 1994, 94, No. 1, pp. 31-75 JP-A-6-202177

  The present invention aims to solve the problems of the prior art as described above. In addition to excellent functional performance, the cohesiveness is low, the compatibility with the binder is excellent, and oxidation resistance, sublimation resistance, etc. By using an excellent specific functional organic compound, a polymer binder having a high glass transition temperature can be effectively utilized, and an organic functional material having excellent functional performance and excellent stability, and use thereof It is to provide an organic functional element.

As a result of intensive studies on functional organic compounds and binder polymers in order to solve the above problems, the present inventors have solved the above problems by utilizing functional organic compounds having a specific structure. As a result, the present invention has been completed.
That is, the said subject is solved by the following this invention.

<1> An organic functional material comprising an isoindole compound represented by the following general formula (1) as an organic functional compound.

(In the formula, L represents a π-conjugated group which may have a substituent, A represents an electron-withdrawing group which may have a substituent, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent an organic group, and any of R ^{2 to} R ⁵ , L and A may be linked to each other to form a ring structure.
<2> The organic function according to <1>, wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an aromatic group which may have a substituent. Sex material.

<3> The organic functional material according to claim 1 or 2, wherein L in the general formula (1) has a structure represented by the following general formula (2).

(In the formula, Z represents an aromatic group which may have a substituent, X ¹ and X ² each independently represent N or CH, and L ′ is included in the ring structure or directly linked to the ring structure. Or a π-conjugated group which is composed of an unsaturated bond adjacent to the ring structure and may have a substituent (m represents 0 or 1).

<4> In the general formula (1), <1> to <3>, wherein A is an electron-withdrawing π-conjugated group having a nitro group, a cyano group, or a carbonyl group and including a ring structure Organic functional material of any one of these.

<5> The organic functional material according to any one of <1> to <4>, wherein the organic functional compound is dispersed or bonded to a polymer binder.

<6> The organic functional material according to <5>, wherein the polymer binder is one or more selected from polyimide, polycarbonate, polyarylate, polysulfone, polycyclic olefin, and fluorine-containing aromatic polyether.

<7> An organic functional element, wherein the organic functional material according to any one of <1> to <6> is applied.

<8> The organic functional element according to <7>, wherein the organic functional element operates with a nonlinear optical function.

  The organic functional material of the present invention has high optical quality and excellent functional performance because the organic functional compound does not aggregate even at a high concentration and takes a uniform dispersion state. In addition, the stability over time is high, and excellent performance can be maintained over a long period of time.

<Organic functional compound>
The present invention is characterized by containing a compound represented by the above general formula (1) as an organic functional compound.
The compound represented by the general formula (1) is a push-pull type π-conjugated compound characterized by having an isoindole structure as an electron donating group, and includes an ambipolar charge transport function, a photocharge generation function, etc. A light emitting function such as a photoluminescence function and an electroluminescence function; a nonlinear optical function such as a harmonic generation function, an electro-optical function, and a photorefractive function;

  In addition, “Chemistry of Materials, 2003, Vol. 15, pp. 3148-3151” shows that the isoindole compound having the structure shown below has a positive charge (hole) transport function and a photoluminescence function, and is amorphous. It is disclosed that it is excellent in performance. This compound is a compound having an electron donating group at both ends of the π-conjugated chain, and does not fall within the category of the push-pull type π-conjugated compound of the present invention, and is a push having an isoindole structure as an electron donating group. There was no disclosure of a pull type π-conjugated compound, and its characteristics were unknown.

  L in the general formula (1) is a π-conjugated group which may have a substituent, and when the unsaturated bond of 5 or more unsaturated bonds are formed on both ends thereof, the nonlinear optical performance In particular, a particularly preferable effect is exhibited. Specific examples of L in which 5 or more unsaturated bonds are formed continuously on both ends include the following. In addition, both ends are indicated by *, and numbers are added to unsaturated bonds that are continuous over both ends.

Furthermore, when L has the structure represented by the general formula (2), preferable effects such as easy synthesis and high chemical stability are exhibited.
Z in the general formula (2) is an aromatic group which may have a substituent, preferably a substituted or unsubstituted 1,4-phenylene group, more preferably an unsubstituted 1,4- A phenylene group.
A in the general formula (1) is an electron-withdrawing group which may have a substituent, and in particular, an electron-withdrawing group having at least a nitro group, a cyano group, or a carbonyl group and including a ring structure A conjugated group is preferred in terms of amorphousness, chemical stability, nonlinear optical performance, and the like. Preferred specific examples of A are shown below. The ends are indicated by *.

R ^{1 to} R ⁶ in the above general formula (1) are organic groups independent of each other, but in terms of chemical stability, amorphousness, etc., those having a bulky and rigid structure are preferable, and aromatic groups are It is particularly preferred. Preferable specific examples of R ^{1 to} R ⁶ include a phenyl group, a methylphenyl group, a dimethylphenyl group, and a methoxyphenyl group.

As a method for synthesizing the compound represented by the general formula (1), any arbitrary method can be used. For example, as shown below, a corresponding isoindole structure (denoted as D) having a formyl group attached thereto via a π-conjugated chain (denoted as L ″) (D-L ″ -CHO), A method of dehydrating and condensing a compound (H ₃ C-A) having a methyl group attached to a corresponding electron-withdrawing group (denoted as A) in the presence of a base is useful. As a synthesis method, D-L "-H was synthesized according to the synthesis method described in" Chemistry of Materials, 2003, Vol. 15, pages 3148-3151 ", and a formylation method such as Vilsmeier method was applied thereto. There is a method of obtaining D-L "-CHO. Further, according to the synthesis method described in “Chemistry of Materials, 2003, Vol. 15, pp. 3148-3151”, D-L ”-CN was synthesized, and the CN group was reduced with a reducing agent such as DIBAL to reduce D-L "There is a way to convert to -CHO.

  The organic functional material of the present invention is characterized by containing the above-mentioned organic functional compound, and can be used in the form of a single crystal, a polycrystal, an amorphous solid, a monomolecular film or the like of the organic functional compound alone. However, in general, 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 forming properties, mechanical strength, etc. in forming an element.

<Binder polymer>
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. Specific examples of particularly preferred binder polymers include polyimide, polycarbonate, polyarylate, polysulfone, polycyclic olefin, fluorine And containing aromatic polyethers.
The functional organic compound represented by the general formula (1) exhibits high compatibility with these polymer binders.
The above organic functional compound is provided as an organic functional material in a state of being dispersed in a microcrystalline state or a molecular state in a binder polymer. It is preferable from the viewpoint of optical quality such as transparency. Further, the above functional organic compound may be chemically linked into the side chain or main chain of the binder polymer.

  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 that can dissolve the organic functional compound used and the binder polymer, but preferably has a boiling point in the range of 100 to 200 ° C. If an organic solvent with a boiling point of less than 100 ° C is used, the solvent volatilization becomes noticeable when the coating solution is stored, and the viscosity of the coating solution changes (increases). , Etc. tend to occur. 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.

  In the organic functional material of the present invention, the content of the functional organic compound varies depending on the type of the functional organic compound used, the required functional performance, mechanical strength, etc. When the function is expected, it is generally preferable that the ratio of the organic nonlinear optical material (organic functional material) in the total weight is in the range of 1 to 90% by weight. The reason is that if it is less than 1% by weight, sufficient functional performance is often not obtained, and if it exceeds 90% by weight, problems such as insufficient mechanical strength tend to occur. It is. A more preferable range of the content of the functional organic compound is 10 to 75% by weight, and further preferably 25 to 60% by weight.

  In addition to the functional organic compound and the binder polymer, various additives can be added to the organic functional material of the present invention as necessary. For example, known antioxidants such as 2,6-di-t-butyl-4-methylphenol and hydroquinone are used for the purpose of suppressing the oxidative degradation of the functional organic compound and / or the binder polymer. / Or known ultraviolet absorbers such as 2,4-dihydroxybenzophenone and 2-hydroxy-4-methoxybenzophenone for the purpose of suppressing ultraviolet degradation of the binder polymer, and when using a wet coating method, the coating thereof 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 a functional organic 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.

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 electrode poling method in which a non-linear optical material is sandwiched between a pair of electrodes and an electric field is applied, and a corona poling method in which a corona discharge is applied to the surface of the non-linear optical material on the substrate electrode and a charging electric field is applied. Is done. 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, by using a binder resin having a higher glass transition temperature, the actual use environment ( In the vicinity of room temperature, this problem can be substantially 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. And solar cells; electroluminescent devices utilizing charge transport and / or electroluminescence functions; laser elements or optical amplification elements utilizing photoluminescence functions; nonlinear optical functions such as harmonic generation functions, electro-optic functions, and photorefractive functions Nonlinear optical elements that utilize 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, etc. can be used.
A conductive film is formed on the surface of these substrate materials as necessary. 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 use known dry film formation methods such as vapor deposition and sputtering, and known wet film formation methods such as spray coating, dip coating, electrolytic deposition, plating, and electroless plating. And a pattern may be formed if necessary. The conductive substrate or the conductive film formed on the substrate is used as an electrode (hereinafter, abbreviated as “lower electrode”) at the time of polling or operation as an element.

  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 the unevenness of the substrate surface, or these functions are provided. Some intermediate layer provided in a lump may be formed. The material for forming such a layer 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 alkoxide compound, a titanium alkoxide compound, a silane coupling agent and the like, and 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.
It is desirable to form a cladding layer (hereinafter abbreviated as “lower cladding layer”) 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, UV-curable or thermosetting resins such as acrylic, epoxy, and silicone; polyimide; SiO _{2 and the} like are preferably used.

After the core layer made of the nonlinear optical material of the present invention is formed, a clad layer (hereinafter, abbreviated as “upper clad layer”) may be further formed thereon 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, etc., and a channel-type waveguide structure or a ridge-type waveguide is formed. A waveguide structure can also be formed. Alternatively, a channel-type or ridge-type waveguide structure 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.

Forming a basic electro-optic element by forming an electrode (hereinafter abbreviated as “upper electrode”) for applying an input electric signal to the surface of the upper clad layer in a desired region of the upper clad 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-Zehnder 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.

Example 1
On a glass substrate provided with a pair of gold parallel electrodes (distance between electrodes = 20 μm) on the surface, the following structural formula which is one of the compounds represented by the general formula (1) as an organic functional compound Poly [Bisphenol A carbonate-co-4,4 '-(3,3,5-trimethylcyclohexylidene) diphenol carbonate] (produced by Aldrich, glass transition temperature) A solution (coating solution A) prepared by dissolving 7 parts in 200 parts at 70 ° C in 80 parts by weight of cyclopentanone (boiling point 130 ° C), a general-purpose non-halogen coating solvent, is applied by spin coating. The film was dried at 30 ° C. for 30 minutes to obtain a thin film having a thickness of 0.2 μm.

Next, the thin film was held at 150 ° C. for 10 minutes with an electric field of 40 V / μm applied between the electrodes, and after cooling to room temperature while applying the electric field, the electric field was removed.
When the thin film subjected to electric field poling of the present invention thus obtained was irradiated with semiconductor laser light having an oscillation wavelength of 1550 nm, the generation of the second harmonic of 775 nm could be observed, and this thin film was a nonlinear optical material. As a result, it was confirmed that it functions effectively. Furthermore, after the thin film was held in a high temperature environment of 65 ° C. for 10 days, when the laser beam was irradiated again, the generation of the second harmonic having the same intensity as the initial can be confirmed, and the nonlinear optical material of the present invention It was confirmed that it had high heat resistance and stability over time.
In addition, when this thin film was observed with the optical microscope, it was very clear and it has confirmed that the compound of the said structural formula was molecularly dispersed uniformly in the polycarbonate.

(Comparative Example 1)
A thin film was prepared in the same manner as in Example 1 except that the organic functional compound in Example 1 was changed to the compound having the following structure described in “Chemstry of Materials, 2001, Vol. 13, pages 3043-3050”. As a result, microcrystals of the following compounds were precipitated, and a clear film could not be obtained.

(Comparative Example 2)
A thin film was produced in the same manner as in Example 1 except that the organic functional compound in Example 1 was changed to the compound having the following structure described in “Chemistry of Materials, 2003, Vol. 15, pages 3148-3151”. Then, when the nonlinear optical performance was evaluated in the same manner as in Example 1, the generation of the second harmonic was not observed, and it was confirmed that this thin film does not function as a nonlinear optical material.

(Example 2)
On a glass substrate (2cm x 2cm) on which a gold thin film as a lower electrode was formed by sputtering, UV curable allyl resin (Norland, product name NOA72) was applied by spin coating, and 100mW / cm After irradiating ² ultraviolet light (high pressure mercury lamp manufactured by USHIO INC.) For 30 seconds, a heat treatment at 120 ° C. for 30 minutes was performed to form a thin film having a thickness of 3 μm, which was used as a lower cladding layer.
Next, the coating liquid A used in Example 1 is applied onto the lower cladding layer by spin coating, and dried at 100 ° C. for 1 hour to form a thin film having a thickness of 2 μm. did.
Next, on the core layer, the same UV curable allyl resin as the lower clad layer was formed in the same manner as the lower clad layer to form an upper clad 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 using a normal photolithography method and a sputtering method.
The sample obtained as described above is cut into a 5 mm wide chip by a dicer (manufactured by Disco), and the cut surface is polished with sandpaper to produce a slab type waveguide device having the configuration shown in FIG. did.
Next, an electric field poling treatment was performed in the same manner 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 poling treatment 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, pp. 320 to 326”. The characteristics were evaluated. A schematic configuration diagram of the evaluation system is shown in FIG. Laser light (semiconductor laser, oscillation wavelength 1310 nm) that has passed through the polarizer 23a is incident from one end face of the element, propagates through the core layer in the element, and is emitted from the other end face to the polarizer 23b. After passing, it was detected by a photodetector. When an electric field was applied between the upper and lower electrodes of the device and the electric field strength was changed from 0 V to 5 V, it was confirmed that the detected light intensity decreased as the electric field strength 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. In addition, after the nonlinear optical element was kept in a high temperature environment of 65 ° C. for 10 days, the same evaluation was performed again. As a result, light modulation characteristics equivalent to those in the initial stage could be confirmed, and the electro-optical element had high heat resistance and time-lapse. It was confirmed to have stability.

(Comparative Example 3)
Except that the nonlinear optically active organic compound in Example 2 was changed to DR1, an electro-optic element was prepared in the same manner as in Example 2, and evaluated in the same manner as in Example 2. As a result, the applied electric field strength was changed from 0V to 5V. When changed, the light modulation amount was very low, one tenth or less of the light modulation amount of Example 1. Further, after storage at 65 ° C. for 10 days, the precipitation of DR1 microcrystals was observed, and it could not be used as an electro-optical element.

  As described above, the organic functional material of the present invention has an organic functional compound having a specific structure excellent in functional performance such as nonlinear optical function, polymer compatibility, heat resistance, and sublimation resistance, and has a high glass transition temperature. It is characterized by being dispersed or bonded to a polymer binder that has high optical quality and excellent functional performance because the organic functional compound does not aggregate even at a high concentration and takes a uniform dispersion state. Has high heat resistance in the alignment state and stability over time, and has the effect of maintaining excellent performance 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 can be realized.

FIG. 5 is a schematic cross-sectional view of devices produced in Example 2 and Comparative Example 3. 5 is a schematic diagram of an evaluation system used in Example 2 and Comparative Example 3. FIG.

Explanation of symbols

11 Glass substrate
12 Bottom electrode
13 Lower cladding layer
14 Core layer
15 Upper cladding layer
16 Upper electrode
21 Laser light source
22 Half-wave plate
23a, 23b Polarizer
24 lenses
25 Power supply
26 pinhole
27 photodetector
28 Electro-optic element

Claims (8)

An organic functional material comprising an isoindole compound represented by the following general formula (1) as an organic functional compound.

(In the formula, L represents a π-conjugated group which may have a substituent, A represents an electron-withdrawing group which may have a substituent, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ each independently represent an organic group, and any of R ^{2 to} R ⁵ , L and A may be linked to each other to form a ring structure. The organic functional material according to claim ¹ , wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ and R ⁶ are each independently an aromatic group which may have a substituent. The organic functional material according to claim 1 or 2, wherein L in the general formula (1) has a structure represented by the following general formula (2).

(In the formula, Z represents an aromatic group which may have a substituent, X ¹ and X ² each independently represent N or CH, and L ′ is included in the ring structure or directly linked to the ring structure. Or a π-conjugated group which is composed of an unsaturated bond adjacent to the ring structure and may have a substituent (m represents 0 or 1).   4. The general formula (1), wherein A is an electron-withdrawing π-conjugated group having a nitro group, a cyano group, or a carbonyl group and including a ring structure. Organic functional materials described in 1.   The organic functional material according to any one of claims 1 to 4, wherein the organic functional compound is dispersed or bonded to a polymer binder.   The organic functional material according to claim 5, wherein the polymer binder is one or more selected from polyimide, polycarbonate, polyarylate, polysulfone, polycyclic olefin, and fluorine-containing aromatic polyether.   An organic functional device, wherein the organic functional material according to claim 1 is applied.   The organic functional element according to claim 7, wherein the organic functional element operates by a nonlinear optical function.

Images