JPH0572581A - Organic nonlinear optical material, nonlinear optical element, and optical modulator - Google Patents

Abstract

PURPOSE:To obtain an excellent nonlinear optical effect of an org. nonlinear optical material so that the material can be used for nonlinear elements such as optical wavelength converter and electrooptic element by constituting the org. nonlinear optical material of a specified org. compd. CONSTITUTION:This org. nonlinear optical material consists of an org. compd. expressed by formula I. In formula I, A is an acceptor type substituent, D is a donner type substituent, phi1, phi2 are independently aromatic rings or heterorings, R1-R4 are independently hydrogen atoms or groups selected from alkyl groups, aryl groups, aralkyl groups and alkyloxy groups, and i-1 are intergers >1. Namely, this org. nonlinear optical material consists of a compd. expressed by formula I, in which polarization of phi is generated by coupling of the acceptor type substituent A to phi1 to promote polarization of the whole compd. expressed by formula I. Thereby, adjacent molecules hardly form a centrical symmetry, and the obtd. material has excellent transparency and good nonlinear optical property.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organic non-linear optical material used in the field of optical information communication or optical information processing, a non-linear optical element such as an optical wavelength conversion element and an electro-optical element using the same, and such a non-linear optical element. The present invention relates to a light modulation device including an optical element.

[0002]

BACKGROUND OF THE INVENTION Organic nonlinear optical materials have recently attracted attention in the fields of optical information communication or optical information processing. The non-linear optical material means a material that exhibits a non-linear optical effect such as converting laser light into light of an arbitrary wavelength or changing the refractive index by applying a voltage. / 2 wavelength light (second
A second-order organic nonlinear optical material having a harmonic oscillation effect was reported in 1983 (ACS Symposium Series 233 (1983)).
Since then, it has been attracting attention as a material showing performance exceeding inorganic materials. For example, as a typical inorganic material, KTi
OPO ₄ (KTP) is known, but the development of organic nonlinear optical materials exceeding the nonlinear optical performance of KTP is expected.

Such a secondary organic nonlinear optical material has, for example, an aromatic ring, a donor substituent and an acceptor substituent, and the π electron of the aromatic ring has a donor substituent and an acceptor substituent. A material having a structure that is polarized in the molecule by a group is mentioned. It is considered that this type of material has extremely high nonlinear optical responsivity because nonlinear optical properties occur at the π electron site.

However, when para-nitroaniline, which is expected to have a high nonlinear optical response, is made into a single crystal state which is practically indispensable as a nonlinear optical element such as an optical wavelength conversion element or an electro-optical element, two adjacent molecules are inverted from each other. The resulting structure has a non-linear optical property. As described above, the organic non-linear optical material tends to lose its non-linear optical property when adjacent molecules have central symmetry. Therefore, organic compounds having a substituent that eliminates such symmetry between adjacent molecules or a substituent that imparts optical activity has been synthesized. For example, 2-synthesized in this way
Methyl-4-nitroaniline has been shown to exhibit high nonlinear optical properties.

Organic nonlinear optical materials have higher nonlinear optical properties as the intramolecular polarizability increases, but if the intramolecular polarization is too high, charge transfer occurs and the transparency of the material is lost. At the same time, the wavelength of the second-order harmonic matches the maximum absorption wavelength λ _max of the organic nonlinear optical material, and the second-order harmonic cannot be efficiently extracted. Further, in order to obtain an organic nonlinear optical material, a nitro group having a high acceptor property and an amino group having a high donor property are introduced at both ends of a linear molecule such as stilbene. However, the material obtained in this manner has problems that adjacent molecules are likely to have central symmetry and that transparency is poor.

In order to solve these problems, methods such as limiting the length of the π-electron conjugated system in the molecule and introducing a hetero atom into the aromatic ring have been tried, but the fundamental method is No solution has been found. In addition, in the related art, there is also a problem that a single crystal organic nonlinear optical material having a size suitable for use as a nonlinear optical element cannot be obtained. That is, in most cases, conventional organic nonlinear optical materials are fine needle-shaped crystals or single crystals whose size is less than 1 mm square and 1 mm square or more, particularly 5 mm square.
There is a problem that it is difficult to obtain a single crystal organic nonlinear optical material having a size of mm square or more.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and is a novel organic non-linear structure which is unlikely to have central symmetry between adjacent molecules, has excellent transparency, and has good non-linear optical properties. When the optical material, particularly the organic nonlinear optical material is a single crystal, the organic nonlinear optical material is such that the single crystal has a size of 1 mm square or more, a light wavelength conversion element using such an organic nonlinear optical material, It is an object of the present invention to provide a non-linear optical element such as an electro-optical element and an optical modulator equipped with the non-linear optical element.

[0008]

SUMMARY OF THE INVENTION The organic nonlinear optical material according to the present invention has the following general formula (I).

[0009]

[Chemical 2]

(Wherein A is an acceptor substituent, D is a donor substituent, Φ ₁ and Φ ₂ are each independently an aromatic ring or a heterocycle, and R _{1 to} R ₄ are Each independently represents a hydrogen atom or a group selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an alkyloxy group, and i to l are organic compounds represented by 1 or more). Is characterized by.

The nonlinear optical element according to the present invention is characterized by being made of such an organic nonlinear optical material. Furthermore, the optical modulator according to the present invention is characterized by including such a non-linear optical element.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The organic nonlinear optical material according to the present invention will be specifically described below. The organic nonlinear optical material of the present invention comprises a compound represented by the above formula (I), resulting polarization of [Phi ₁ by acceptor substituent A is bonded to the [Phi _1, total Arawasaru compound of formula (I) Polarization is promoted.

The acceptor substituent A preferably has a Hammett value σ in the range of 0 <σ <0.8. Such substituents are specifically exemplified by nitro group, cyano group, trifluoromethyl group, trifluoromethylmethoxy group, trifluoromethylthio group, carbamoyl group, nitroso group, cyanato group, thiocyanato group, isocyanato group, Formyl group,
Alternatively, an alkoxycarbonyl group such as methoxycarbonyl and ethoxycarbonyl, a halogenated alkoxycarbonyl group, an acetyl group, a propinoyl group, an acyl halide group, a sulfo group, a sulfino group, a sulfeno group, a halogen atom and the like can be mentioned. Of these, a nitro group is preferable.

[0014] acceptor substituent A is and one or more binding to [Phi _1, when a plurality of A is bonded to [Phi _1, each of A being the same or different May be. Such an acceptor substituent A
Is preferably bound to Φ ₁ so that the polarization of Φ ₁ is promoted. For example, when Φ ₁ is a benzene ring, the acceptor substituent A is —NR ₂ NR ₃ CO—.
It is preferable that Φ ₁ is bonded to the bond at a para position with respect to the bond (carbohydrazide bond), and if there are a plurality of acceptor substituents A, a para position and a bond with respect to the carbohydrazide bond as described above and It is preferably bound to Φ ₁ at the meta position.

[0015] The resulting polarization to ₂ [Phi by donor substituents attached to the same manner [Phi _2, the polarization of the entire compound represented by the formula (I) is promoted. The donor substituent D preferably has a Hammett value σ in the range of 0 ≧ σ ≧ −0.83. Such substituents are specifically exemplified by hydrogen atom, dimethylamino group, amino group, hydroxy group, aryloxy group such as phenoxy group, alkyloxy group such as methoxy group, methyl group,
Linear alkyl groups such as ethyl group, n-propyl group, n-butyl group, secondary alkyl groups such as isopropyl group, sec-butyl group, sec-amyl group, tert-butyl group, tert-amyl group, etc. Examples include tertiary alkyl groups, aryl groups, thioalkyl groups, and the like. Of these, a methoxy group is preferable.

The donor substituent D is to one or more binding to [Phi _2, when a plurality of D is attached to [Phi _2, each of the D being the same or different May be. It is preferable that the donor substituent D is bonded to Φ ₂ so that the polarization of Φ ₂ is promoted. For example, when Φ ₂ is a benzene ring, the donor substituent D is preferably bonded to Φ ₂ at the para position with respect to the carbohydrazide bond, and when there are a plurality of donor substituents D. Is preferably bound to Φ ₂ at the para and meta positions with respect to the carbohydrazide bond as described above.

When Φ ₁ and Φ ₂ are benzene rings, in particular, A is bound to Φ ₁ in the para position to the carbohydrazide bond and D is bound to Φ ₂ in the para position to the carbohydrazide bond. In this case, the intramolecular polarization effect is the highest, which is preferable. Φ ₁ and Φ ₂ in the above formula (I) are each independently an aromatic ring or a hetero ring, preferably an aromatic ring, a 5-membered hetero ring or a 6-membered hetero ring, and particularly preferably a benzene ring or a 5-membered hetero ring. preferable. These aromatic rings or heterocycles provide a field for electronic resonance,
The non-linear optical effect is effectively exhibited by these rings. Specific examples of the aromatic ring or hetero ring used for Φ ₁ and Φ ₂ are as follows.

[0018]

[Chemical 3]

[0019]

[Chemical 4]

[0020]

[Chemical 5]

R ₁ to R ₄ in the above formula (I) are each independently a hydrogen atom or a group selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an alkyloxy group. Of these, R ₁ and R ₄ are preferably an alkyl group, particularly preferably a methyl group or an ethyl group, and R ₂ and R ₃ are preferably hydrogen atoms.

The above-mentioned alkyl group may be linear or branched and has 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms. As such an alkyl group, specifically, a methyl group, an ethyl group, an n-propyl group,
linear alkyl group such as n-butyl group, isopropyl group,
sec-butyl group, sec-amyl group and other secondary alkyl groups, te
Examples thereof include tertiary alkyl groups such as rt-butyl group and tert-amyl group.

The above aryl group may have a substituent. As such an aryl group, specifically,
Examples thereof include a phenyl group, a naphthyl group, a tolyl group and a xylyl group. Specific examples of the aralkyl group include:
Examples thereof include a benzyl group, a phenethyl group, an α-methylbenzyl group and a tolylmethyl group.

The above alkyloxy group may be linear or branched and has 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms. As such an alkyl group, specifically, a linear alkyloxy group such as methyloxy group, ethyloxy group, n-propyloxy group, n-butyloxy group, isopropyloxy group, sec-butyloxy group, sec- Examples thereof include secondary alkyloxy groups such as amyloxy groups, tertiary alkyl groups such as tert-butyloxy groups and tert-amyloxy groups.

In the above compound, adjacent molecules are
R at a position where center symmetry does not occur ₁And / or R_Four
Are preferably arranged. For example Φ₁and
Φ₂When is a benzene ring, R₁Is carbohydrazide
Ortho to Φ₁Is bound to R_Four
Is Φ at the meta position with respect to the carbohydrazide bond₂Bound to
Or R₁Pair with the carbohydrazide bond
And Φ in meta position₁Is bound to R_FourIs carbo
Φ in the ortho position to the hydrazide bond₂Is bound to
Preferably. In this case, two R₁Are each
Φ in the ortho position with respect to the lubohydrazide bond₁Is bound to
Or two R_FourEach is carbohydra
Φ in the ortho position with respect to the zido bond₂May be bound to
Yes. Φ₁Multiple R₁Are bound together, respectively
R₁May be the same or different from each other, Φ₂
Multiple R_FourAre bound, each R_FourAre each other
May be the same or different.

Further, R ₂ and / or R ₃ are preferably both optically active groups. When R ₂ and / or R ₃ is an optically active group, the symmetry of the molecule is broken, and when a single crystal is produced, it is difficult for adjacent molecules to have central symmetry, and the nonlinear optical property is effectively maintained. Here, the optically active group means a group having an asymmetric carbon atom, for example, a substituent in which three different groups, a methyl group, an ethyl group, and a hydrogen atom are bonded to one carbon atom.

The compound represented by the formula (I) preferably has at least one deuterium.
Specific examples of the compound represented by the above formula (I) include the following compounds.

[0028]

[Chemical 6]

[0029]

[Chemical 7]

[0030]

[Chemical 8]

As the compound represented by the above formula (I), 4-nitrophenyl-4'-methoxyphenylcarbohydrazide represented by the above chemical formula (1) is particularly preferable. Such a carbohydrazide derivative can be obtained by subjecting a hydrazine derivative having a Φ ₁ skeleton and an acid chloride having a Φ ₂ skeleton to a condensation reaction in the presence of a base.

Examples of the base used in this reaction include pyridine, trimethylamine, triethylamine and the like, and pyridine or trimethylamine is particularly preferable. Also, these bases can be used in combination.
The carbohydrazide derivative can be obtained through the reaction of the following formula, taking as an example the case where a hydrazine derivative in which R ₂ and R ₃ are both hydrogen atoms is used as a raw material.

[0033]

[Chemical 9]

As is clear from the above reaction formula, HCl is generated during the condensation of the hydrazine derivative and the acid chloride,
In order to proceed the reaction, it is necessary to neutralize this HCl with a base, and usually 1.0 to 5 mol, preferably 2 to 1 mol with respect to 1 mol of the hydrazine derivative or acid chloride.
5 moles of base are used. Also, this reaction is usually
It is performed in the liquid phase. At the time of this reaction, a solvent that is chemically inert to the hydrazine derivative and acid chloride used as the raw materials, and the carbohydrazide derivative formed further, and that dissolves the hydrazine derivative and the acid chloride used as the raw materials, is used. Used. Examples of such solvent include various solvents such as aromatic hydrocarbon solvents, aliphatic saturated hydrocarbon solvents, aliphatic saturated halogenated hydrocarbon solvents, aliphatic unsaturated hydrocarbon solvents and ether solvents. Is used, and dichloromethane and THF are particularly preferable. These solvents are used alone or as a mixture of two or more kinds.

The above reaction is usually carried out in the temperature range of -20 to 100 ° C, preferably 0 to 50 ° C. The reaction can be carried out under reduced pressure, usually under a pressure of 60 kg / cm ² , but is preferably carried out under a pressure of 0 to 30 kg / cm ² , especially 0 to 5 kg / cm ² .
The reaction time is appropriately set depending on the reaction temperature, pressure conditions and the like and is not particularly limited, but is usually 5 to 100 hours, preferably 1 to 10 hours.

Further, the above reaction is usually carried out under an inert atmosphere such as argon or nitrogen. The organic nonlinear optical material according to the present invention comprises the compound represented by the above formula (I), and is used in a nonlinear optical element in a crystallized state. The organic nonlinear optical material according to the present invention,
Usually, one type of compound represented by formula (I) is used, but a plurality of types of compound represented by formula (I) may be used.

The crystal of the compound represented by the formula (I) may be a eutectic crystal with another component having a similar crystal structure, or may be a powdery polycrystal. However, it is preferably a single crystal. Furthermore, the organic nonlinear optical material according to the present invention may be a composite of the compound represented by the above formula (I) and a transparent polymer.

The single crystal as described above is prepared by dissolving the compound represented by the above formula (I) in a suitable solvent such as dimethylformamide, ethanol, etc., and then evaporating the solvent or the obtained solution. It is obtained by lowering the temperature of and crystallizing the compound contained in the solution. Further, the single crystal as described above can be represented by the above formula (I) by a vacuum vapor deposition method, a molecular beam epitaxy method or the like by heating and melting the compound represented by the above formula (I) and then cooling and crystallizing it. It can also be obtained by vapor-phase growth of the compound described above.

According to the organic nonlinear optical material of the present invention, a large single crystal composed of a rectangular parallelepiped having a size of 1 mm square or more can be provided by the above method. Particularly, in the above formula (I), A is a nitro group, D is a hydrogen atom, one kind of substituent selected from an alkyl group and an alkyloxy group, Φ ₁ and Φ ₂ are benzene rings, R _{1 to} R ₄ are all hydrogen atoms, and i = 1, j Is 1 or 2 and A
5 mm when (nitro group) is bonded to Φ ₁ (benzene ring) at the para position with respect to the carbohydrazide bond
A large single crystal with a corner or more can be provided.

A nonlinear optical element according to the present invention can be obtained by adding a cutting step and a processing step to a large single crystal made of the organic nonlinear optical material according to the present invention as described above. Further, when the nonlinear optical element according to the present invention is formed from the thin film single crystal obtained as described above, the thickness of the thin film single crystal is preferably 1 μm or more.

A composite of a transparent polymer and one or more compounds represented by the formula (I) as described above is represented by the formula (I) as described above in a polymer matrix. After dispersing one or more compounds, a voltage is applied to this dispersion while heating the resulting dispersion at a temperature above the glass transition point, whereby the compounds contained in this dispersion are Can be obtained by a method of orienting and cooling and solidifying while maintaining this orientation.

In the non-linear optical element according to the present invention, the composite of the one or more compounds represented by the above formula (I) thus obtained and the transparent polymer is desired. It is obtained by processing into a shape. An optical modulator according to the present invention includes the above-described nonlinear optical element according to the present invention, and is used as a second harmonic generation device, an optical switch, or the like.

FIG. 1 shows an example of the second harmonic generation device according to the present invention. This second harmonic generation device 10 is shown.
Includes a laser light source 11, a condenser lens 12, a nonlinear optical element 13, a condenser lens 14, and an infrared cut filter 15. According to the second harmonic generation device 10, the laser light emitted from the laser light source 11 is condensed in the nonlinear optical element 13 by the condenser lens 12.
When the laser light enters the non-linear optical element 13 in this manner, the second harmonic is generated by the non-linear optical element 13, and the fundamental wave of the laser light and the second harmonic are generated from the non-linear optical element 13.
Light including light having harmonics is emitted. The emitted light is converted into substantially parallel light by the condenser lens 14, and the substantially parallel light is selectively output as light having the second harmonic through the infrared cut filter 15.

The second harmonic generation device 20 shown in FIG.
Is a laser light source 21, a condenser lens 22, a core material 23 and a core material 2 made of an organic nonlinear optical material according to the present invention.
The core material 23 is covered with a clad material 24, which is made of a medium such as highly transparent glass having a refractive index different from that of the core material 3. According to the second harmonic generation device 20, the laser light emitted from the laser light source 21 passes through the condenser lens 22 from one end of the core material 23 to the core material 23.
It is incident on the inside and propagates in the core material 23. Further, the laser light emitted from the laser light source 21 generates a second harmonic in the process of propagating in the core material 23, and the light having the second harmonic is output from the other end of the core material 23. ing.

The optical modulator 30 shown in FIG. 3 further includes a laser light source 31, a condenser lens 32, and a substrate 34 on which a waveguide 33 made of the organic nonlinear optical material according to the present invention is formed. Of these, the waveguide 33 is bifurcated on the substrate 34 to form two branched paths having the same optical path length, and these branched paths join again.
Further, a pair of electrodes 35 connected to an external power source (not shown) are arranged on both sides of one branch path.

According to this optical modulator 30, the laser light emitted from the laser light source 31 is incident on one end of the waveguide 33 through the condenser lens 32, the laser light is branched along the branch path, and merges again. Then, the light is output from the other end of the waveguide 33. Here, when a voltage is applied between the pair of electrodes 35, the refractive index of the organic nonlinear optical material forming the branch path sandwiched between the pair of electrodes 35 changes,
As a result, the phase of the laser light that passes through this branch path is modulated, and the phase and intensity of the output light that is the combined light of the laser light that passes through both branch paths can be changed. To be done.

[0047]

As described above, the organic nonlinear optical material according to the present invention comprises the organic compound represented by the above formula (I), and a resonance field is given by the Φ ₁ ring and the Φ ₂ ring.
The molecular polarization and the molecular arrangement are controlled in a balanced manner by A, D, R ₁ to R ₄ , and adjacent molecules do not have central symmetry, so that an excellent nonlinear optical effect is obtained.

Further, according to the present invention, a large single crystal organic non-linear optical material can be provided, and particularly in the formula (I), A is a nitro group, D is a hydrogen atom,
One substituent selected from an alkyl group and an alkyloxy group, Φ ₁ and Φ ₂ are benzene rings, and R ₁
To R ₄ are all hydrogen atoms, i = 1, j is 1 or 2
When A (nitro group) is bonded to Φ ₁ (benzene ring) at the para position with respect to the carbohydrazide bond, a large single crystal of 5 mm square or more can be easily provided.

Therefore, the organic nonlinear optical material according to the present invention is an optical wavelength conversion element utilizing a second-order nonlinear optical effect,
It is suitable for application to a non-linear optical element such as an electro-optical element, and the non-linear optical element thus obtained is
It is suitable as a main component of an optical modulator such as an optical switch used in the field of multiplex optical communication.

[0050]

EXAMPLES The present invention will be described below based on more specific examples, but the present invention is not limited to these examples.

[0051]

Example 1 A 300 ml three-necked flask was charged with 100 ml of dichloromethane and 1.60 g of p-nitrophenylhydrazine. The mixture was stirred at room temperature, 20 cc of pyridine was further added, and 1.7 cc of p-methoxybenzoyl chloride was slowly added dropwise from the dropping funnel to immediately precipitate a yellow precipitate. Further, the liquid in which the yellow precipitate was deposited was stirred at room temperature for 12 hours, and after completion of the reaction was confirmed by thin-layer chromatography, the liquid was hydrolyzed, and then the obtained oil layer was separated and washed with water. The layer was extracted with dichloromethane, combined with the oil layer and dried in vacuo. After that, reprecipitation was carried out with tetrahydrofuran / hexane, and 2.
75 g of powder was obtained.

The molecular structure of this powder was identified by NMR. As a result, 4'-nitrophenyl represented by the above chemical formula (1) was obtained.
-4-Methoxyphenyl carbohydrazide (hereinafter NMC
It is called H. ) Was found (see FIG. 4). The melting point of this powder was measured by the DSC method to find that it was 24
It was 8 ° C. Then, using this NMCH powder, SHG intensity measurement was performed by a powder method. A YAG laser was used for input. The SHG intensity of this powder was 21.4 times the SHG intensity of the urea powder measured in the same manner.

Further, when NMCH powder was dissolved in a DMF solvent and left at room temperature for about 10 days, 15 × 10 × 6 was obtained.
A single crystal with a size of mm was obtained. The size of this single crystal corresponds to about 10 times the size of the single crystal obtained by similarly growing crystals of 2-methyl-nitroaniline (MNA). In the following examples, the size of this single crystal is
The evaluation was made according to the following three grades.

Large: When the single crystal is a rectangular parallelepiped of 5 mm square or more Medium: When the single crystal is a rectangular parallelepiped of 1-5 mm square Small: When the single crystal is a rectangular parallelepiped of 1 mm square or less, or a needle crystal Table 1 shows the above evaluation results.

An X-ray structural analysis of the thus obtained NMCH single crystal showed that the space group belongs to the orthorhombic system (Pbn2 ₁ ), and the lattice constant is a = 26.9 angstrom, b = 10.65 Angstrom, c
= 4.7 angstroms. Also, this NMC
When an HAG single crystal was irradiated with a YAG laser (wavelength; 1064 nm, continuous wave, output: 175 mW), SH light (53 nm) compatible with phase matching only at a certain incident angle was obtained.
2 nm) sharp peak was obtained. When the SH light intensity was measured, it showed a value 7 times larger than that when a KTP crystal (sample length: 5 mm) was used.

In the following examples, the SH light intensity of the single crystal thus obtained is compared with the SH light intensity of the KTP crystal, and the SH light intensity of the single crystal obtained as described below is compared. evaluated. ⊚: 5 times or more of SH light intensity of KTP crystal ◯: 1 to 5 times of SH light intensity of KTP crystal Δ: Less than 1 time of SH light intensity of KTP crystal Table 1 shows the evaluation results.

Further, the chemical stability (discoloration resistance) of the obtained single crystal, the size of the single crystal, and the S of the obtained single crystal.
The suitability as a nonlinear optical element was comprehensively evaluated from the H light intensity and chemical stability. The chemical stability of single crystals is
It was evaluated as unstable when the single crystal was oxidized and discolored with time when left standing, and as stable when the single crystal was not discolored with time. Table 1 shows the above evaluation results.

[0058]

Example 2 Example 1 was repeated except that 2.0 g of 2,6-dimethoxybenzoyl chloride previously dissolved in dichloromethane was used instead of p-methoxybenzoyl chloride.
In the same manner as above, 1.66 g of a powder of 4'-nitrophenyl-2,6-dimethoxyphenylcarbohydrazide represented by the chemical formula (2) was obtained. The molecular structure of this compound was identified by NMR. In addition, the melting point of this powder is DS
It was 250 ° C. when measured by the C method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
It was 8.8 times the strength. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0060]

Example 3 Benzoyl chloride 1.4 diluted with dichloromethane instead of p-methoxybenzoyl chloride
In the same manner as in Example 1 except that cc was used, 0.9 g of 4′-nitrophenyl-phenylcarbohydrazide represented by the above chemical formula (3) was obtained. The molecular structure of this compound was identified by NMR (see FIG. 5). The melting point of this powder was 210 ° C. when measured by the DSC method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
It was 21.1 times the strength. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0062]

Example 4 p-toluyl chloride 1.5 diluted with dichloromethane instead of p-methoxybenzoyl chloride
In the same manner as in Example 1 except that 4 cc was used, 2.5 g of 4'-nitrophenyl-4-methylphenylcarbohydrazide represented by the above chemical formula (4) was obtained. The molecular structure of this compound was identified by NMR (see FIG. 6). The melting point of this powder was measured by the DSC method to find that it was 24
It was 5 ° C.

When the SHG intensity of the obtained powder of the compound was measured in the same manner as in Example 1, the SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
The strength was 21.7 times. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0064]

Example 5 50 ml of dichloromethane and 1.60 g of p-nitrophenylhydrazine were placed in a 200 ml two-necked flask. The mixture was stirred at room temperature and then pyridine 1 was added.
After adding 5 cc, 2.0 g of 3,4-dimethoxybenzoyl chloride previously dissolved in dichloromethane was slowly added dropwise from the dropping funnel, and then the same process as in Example 1 was carried out, and the compound represented by the above chemical formula (5) was used. '-Nitrophenyl-
2.5 g of 3,4-dimethoxyphenylcarbohydrazide was obtained. The molecular structure of this compound was identified by NMR (see FIG. 7). The melting point of this powder was 220 ° C. when measured by the DSC method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
The strength was 21.8 times. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0066]

Example 6 4'-Nitrophenyl-represented by the above chemical formula (6) was obtained in the same manner as in Example 5 except that 1.4 cc of 2-thenoyl chloride was used instead of 3,4-dimethoxybenzoyl chloride. 2.8 g of thienyl carbohydrazide was obtained.
The molecular structure of this compound was identified by NMR (see FIG. 8). The melting point of this powder was 186.6 ° C. when measured by the DSC method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was found to be the same as that of the urea powder measured in the same manner.
The strength was 24.6 times. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0068]

Example 7 4′-represented by the above chemical formula (7) was obtained in the same manner as in Example 5 except that 1.84 g of N, N-dimethylaminophenyl chloride was used in place of 3,4-dimethoxybenzoyl chloride. Nitrophenyl-4 (N, N-dimethylamino)
1.76 g of phenylcarbohydrazide was obtained. The molecular structure of this compound was identified by NMR (see FIG. 9). The melting point of this powder was 252 ° C. when measured by the DSC method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
The strength was 24.6 times. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0070]

Example 8 A 200 ml two-necked flask was charged with 50 ml of dichloromethane and 1.54 g of p-nitrophenylhydrazine. The mixture was stirred at room temperature and then pyridine 1 was added.
After adding 2.5cc, dichloromethane 20c in advance
After slowly adding 1.3 cc of 2-furoyl chloride dissolved in c through the dropping funnel, in the same manner as in Example 1, 4'-nitrophenyl-furylcarbohydrazide 2 represented by the above chemical formula (13) was obtained. 0.45 g was obtained. The molecular structure of this compound was identified by NMR (see FIG. 10). The melting point of this powder was measured by the DSC method and found to be 157.5 ° C.

When the SHG intensity of the obtained compound powder was measured in the same manner as in Example 1, the SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
It was 0.7 times the strength. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0072]

Example 9 A 200 ml two-necked flask was charged with 50 ml of dichloromethane and 0.78 g of p-nitrophenylhydrazine. The mixture was stirred at room temperature, 2.5 cc of pyridine was added, and 20 c of dichloromethane was previously prepared.
4-ethylbenzoyl chloride 0.9c dissolved in c
After slowly dropping c from the dropping funnel, the same procedure as in Example 1 was carried out to obtain 4'-nitrophenyl-4-ethylphenylcarbohydrazide 2.45 represented by the chemical formula (14).
g was obtained. The molecular structure of this compound was identified by NMR (see FIG. 11). In addition, the melting point of this powder is DSC
It was 250 ° C. when measured by the method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
It was 0.5 times the strength. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0074]

Example 10 10 ml of THF was added to a 50 ml two-necked flask.
1.60 g of p-nitrophenylhydrazine was added. This mixture was stirred at room temperature, 17 cc of pyridine was further added, and then 2.19 cc of p-trifluoromethylbenzoyl chloride diluted with THF was slowly added dropwise from the dropping funnel, in the same manner as in Example 1, The chemical formula (1
1.52 g of 4'-nitrophenyl-4-trifluoromethylphenylcarbohydrazide represented by 5) was obtained. The molecular structure of this compound was identified by NMR (Fig.
See 12). The melting point of this powder was 262 ° C. when measured by the DSC method.

The SHG intensity of the obtained compound powder was measured in the same manner as in Example 1. The SHG intensity of this powder was the same as that of the urea powder measured in the same manner.
It was 0.3 times the strength. Then, a single crystal was produced in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0076]

Comparative Examples 1 to 5 Compounds (16) to (2
0):

[0077]

[Chemical 10]

A single crystal was produced from the powder of Example 1 in the same manner as in Example 1, and the size of the obtained single crystal, SH light intensity, chemical stability (discoloration resistance), and comprehensive evaluation were performed. Table 1 shows the above evaluation results.

[0079]

[Table 1]

[Brief description of drawings]

FIG. 1 is a drawing for explaining an example of a light modulation device according to the present invention.

FIG. 2 is a drawing for explaining an example of a light modulation device according to the present invention.

FIG. 3 is a drawing for explaining an example of a light modulation device according to the present invention.

FIG. 4 is an NMR chart of a compound (4′-nitrophenyl-4-methoxyphenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 5 is an NMR chart of a compound (4′-nitrophenyl-phenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 6 is an NMR chart of a compound (4′-nitrophenyl-4-methylphenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 7 is an NMR chart of a compound (4′-nitrophenyl-3,4-dimethoxyphenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 8 is an NMR chart of a compound (4′-nitrophenyl-thienylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 9 is an NMR chart of a compound (4′-nitrophenyl-4 (N, N-dimethylamino) phenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 10 is an NMR chart of a compound (4′-nitrophenyl-furylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 11 is an NMR chart of a compound (4′-nitrophenyl-4-ethylphenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

FIG. 12 is an NMR chart of a compound (4′-nitrophenyl-4-trifluoromethylphenylcarbohydrazide) used in the nonlinear optical material according to the present invention.

[Explanation of symbols]

 10, 20 ... Second harmonic generation device 30 ... Optical modulation device 11, 21, 31 ... Laser light source 12, 14, 22, 32 ... Condensing lens 13 ... Non-linear optical element 15 ... Infrared cut filter 23 ... Core material 24 ... Clad material 33 ... Waveguide 34 ... Substrate 35 ... Electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Toru Yamanaka Toru Yamanaka 580-2 32 Takuji Nagaura, Sodegaura-shi, Chiba Mitsui Petrochemical Industrial Co., Ltd.

Claims (8)

[Claims] 1. A compound represented by the general formula (I): (In the formula, A is an acceptor substituent, D is a donor substituent, Φ ₁ and Φ ₂ are each independently an aromatic ring or a heterocycle, and R _{1 to} R ₄ are each independently Is a hydrogen atom or a group selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an alkyloxy group, and i to 1 are integers of 1 or more.). Organic nonlinear optical material. 2. The organic nonlinear optical material according to claim 1, wherein Φ ₁ and Φ ₂ are benzene rings or 5-membered heterocyclic rings. 3. Φ ₁ and Φ ₂ are benzene rings, and A is bound to Φ ₁ in the para position to the carbohydrazide bond and D is Φ _{2 in the} para position to the carbohydrazide bond. The organic nonlinear optical material according to claim 2, which is bonded to. 4. The organic nonlinear optical material according to claim 1, wherein R ₂ and / or R ₃ is an optically active group. 5. The organic nonlinear optical material according to claim 1, wherein the organic compound represented by the formula (I) has at least one deuterium. 6. In the formula (I), A is a nitro group, D is one kind of substituent selected from a hydrogen atom, an alkyl group and an alkyloxy group, and Φ ₁ and Φ ₂ are benzene rings. And R _{1 to} R ₄ are all hydrogen atoms, and i =
The organic nonlinear optical material according to claim 1, wherein 1, j is 1 or 2, and A is bonded to Φ ₁ in a para position with respect to the carbohydrazide bond. 7. A nonlinear optical element comprising the organic nonlinear optical material according to claim 1. 8. An optical modulator comprising the nonlinear optical element according to claim 7.