JP2670462B2 - Organic nonlinear optical material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an organic nonlinear optical material,
More specifically, the present invention relates to an organic nonlinear optical material made of a phthalocyanine derivative, which is used for optical elements such as wavelength conversion, optical calculation, optical shutter, optical memory and the like.

(Prior art) The polarization P induced when light passes through a substance is given by the following equation when the electric field of light is E: P = ^（(1) E + χ ⁽²⁾ E · E + χ ⁽³⁾ E · E · It is expressed as E + ..., The first term is called linear polarization, and the second and subsequent terms are called non-linear polarization. The coefficient χ ⁽ⁿ⁾ (n ≧ 2), which is a measure of the magnitude of the polarization induced at this time, is the nth-order nonlinear susceptibility, and the effect from the polarization based on the term including χ ⁽ⁿ⁾ is the nth-order nonlinearity. Called the optical effect. χ ⁽ⁿ⁾ is a coefficient that quantitatively expresses the nonlinear optical effect by the (n + 1) th order tensor.
In general, χ ⁽²⁾ , χ ^(3), etc. are minute quantities, and when the light intensity E is small, only the linear effect based on the first term of Eq. (1) is recognized, but χ ⁽²⁾ , χ ^{(3 In} the case of a material with a large ^), the second and higher order terms cannot be ignored under a strong electric field such as laser light, and as a result, a nonlinear optical response appears. The second-order nonlinear optical effects include second harmonic generation (SHG), optical rectification, parametric amplification, and the Pockels effect. The third-order nonlinear optical effects include third harmonic generation,
DC induced SHG, Kerr effect and optical bistability.
Nonlinear optical materials exhibiting these phenomena are being studied for application to new optoelectronic devices. Of these phenomena, optical bistability is the simplest case of optical multistability. Optical multiplicity means that the input light in an optical element
When I _{1 is} the output light and I ₂ is the output light, the relation between them is expressed by a polyvalent function such as I ₂ = F (I ₁ ). The case where there are two types of output light states that take a value is called optical bistability. Which of the two types is taken depends on the history of the system. That is,
There is hysteresis between the two states. This phenomenon can be applied to optical switches, optical storage elements, optical logic elements, and the like.

Non-linear optical materials having the above-described properties are described in detail in, for example, the following literature.

DSCHEMLA, J.ZYSS `` NONLINEAR OPTICAL PROPERTIES OF
ORGANIC MOLECULES AND CRYSTALS ”ACADEMIC PRESS, I
NC., 1987, edited by Masao Kato and Hachiro Nakanishi, "Organic Nonlinear Optical Materials", CMC Co., Ltd., 1985. The search for tertiary nonlinear optical materials is being actively conducted in both inorganic and organic compound domains. Semiconductors such as gallium arsenide and Group III to Group V compounds are known as inorganic materials. Organic materials reported so far are mainly π-conjugated polymers, and polysilane, polyimide, polyacetylene, polythiophene and the like are known as well as polydiacetylene. Especially PDA-P
One type of polydiacetylene called TS is currently known as an organic material having the largest third-order nonlinear optical constant. Also, stilbene derivatives (JP-A-1-273022) are known, and materials in which a π-conjugated compound having a cation in a molecule is dispersed in an ionic polymer (JP-A-1-217328, JP-A-1-217328). No. 1-217329) is also disclosed. As other organic materials, a metal-free or metal phthalocyanine having no substituent or an alkoxy group is disclosed in JP-A-1-237626. This organic material exhibits a third harmonic intensity smaller than that of PDA-PTS when irradiated with light of wavelength 1907 nm. In general, in organic materials, the nonlinear response is caused by π electrons in molecules that are easily polarized, whereas in inorganic materials, electrons related to lattice bonds respond to light. Therefore, the breakdown threshold for laser light is larger in the organic material than in the inorganic material. The response speed of inorganic materials does not exceed picoseconds, whereas the response speed of organic materials is femtoseconds, which is extremely high.

In the case of inorganic materials, the third-order nonlinear susceptibility is 10 ^-2 to 10 ^-5 es
Although it is large as u, the response is slow and is about 10 GHz. On the other hand, as for organic materials, it is not known that the third-order nonlinear susceptibility exceeds 10 ^-8 esu, but there is an advantage that a high-speed response of several tens GHz or more is possible.

When nonlinear optical materials are used as optical switches, optical logic devices, etc., high-speed response is an indispensable property.
In this sense, the importance of organic nonlinear optical materials in these optical related technologies is high.

(Problems to be Solved by the Invention) The third-order organic nonlinear optical material known so far is
It is characterized by a linear or annular structure of π-conjugated systems. However, regarding the non-linear optical characteristics, no one is known that exhibits characteristics higher than those of the PDA-PTS, which is a kind of polydiacetylene.

Even in the case of PDA-PTS, it is difficult to control the π-conjugated chain length required for the development of nonlinear optical properties, and it has the drawback of poor stability in air. Further, there is a problem that it is difficult to form a thin film, which is extremely important in making a non-linear optical material into an element.

An object of the present invention is to provide a novel organic nonlinear optical material which exhibits nonlinear optical characteristics exceeding that of existing organic nonlinear optical materials and does not have the above-mentioned problems associated with existing materials when put into practical use. To do.

[Configuration of the invention]

(Means for Solving the Problem) The present invention provides an organic nonlinear optical material containing at least one phthalocyanine represented by the following formula [1] as a component.

Equation [1] [Wherein, R ^{1 to} R ²² each independently represent a hydrogen atom, a halogen group, a cyano atom, a nitro group, a carboxy group, a sulfo group,
An aliphatic hydrocarbon group which may have a substituent, an aromatic hydrocarbon group which may have a substituent, an aromatic heterocyclic group which may have a substituent, -OR ²³ , -SR ²⁴ , −NR ²⁵ R ²⁶ , −SO ₂ NR ²⁷ R ²⁸ ,
-CONR ²⁹ R ³⁰ , -NHCOR ³¹ , -CO ₂ R ³² , -N = NR ³³ , -X (CH
₂ CH ₂ Y) Represents zR ³⁴ .

R ^{23 to} R ³⁴ are a hydrogen atom, an aliphatic hydrocarbon group which may have a substituent, an aromatic hydrocarbon group which may have a substituent, an aromatic heterocyclic group which may have a substituent Represents X and Y each independently represent an oxygen atom or a sulfur atom, and z represents a positive integer. According to the present invention, the phthalocyanine represented by the formula [1] has a tertiary nonlinear susceptibility equal to or higher than that of an existing organic nonlinear optical material, and does not have any problems that the existing material has in practical use. Is completed.

In the present invention, R ^{1 to} R ²² are hydrogen atoms or halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom,
Has substituents such as cyano, nitro, carboxy, sulfo or methyl, ethyl, tert-butyl, hexyl, octyl, stearyl, trichloromethyl, aminomethyl, hydroxymethyl, etc. Aliphatic hydrocarbon group, phenyl group, naphthyl group, anthryl group, phenanthryl group, aromatic hydrocarbon group which may have a substituent such as 2-methylphenyl group, or pyridyl group, carbazolyl group, furfuryl Group, benzothiazolyl group, aromatic heterocyclic group which may have a substituent such as 4-methylpyridyl group, hydroxyl group, methoxy group, ethoxy group, butoxy group, stearyloxy group, phenoxy group, tert-butylthio group, hexylthio Group, octylthio group, phenylthio group, amino group, butylamino group, diethylamino group, diphenylamino group, di Njiruamino group, butylsulfamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group, octylcarbamoyl group, phenylcarbamoyl group, diethylcarbamoyl group, butyl carbonyl group, phenylcarbonylamino group, -CO
₂ CH ₃ , -CO ₂ C ₂ H ₅ , -CO ₂ Ph (Ph: phenyl group), phenylazo group, 4- (dibutylamino) phenylazo group, 1-naphthylazo group, etc., but are not limited to these substituents It is not something that will be done.

The compound represented by the above formula [1] used in the present invention is produced by reacting the compound represented by the following formula [2] and formula [3].

In the formula [2] and the formula [3], r _{1 to} r ₂₁ are the same as R ^{1 to} R ²¹ in the formula [1], respectively.
Represents a halogen atom.

Regarding the compound represented by the formula [2] in which r ₁ to r ₁₂ are all hydrogen atoms, Monatshefte fr Chemi
e, 103, 150-155 (1972) describes a synthetic method.

The solvent used in the production of the formula [1] dissolves at least a part of the compound represented by the formula [1] and the compound represented by the formula [2] and reacts with the reaction represented by the formula [4]. It must have the property that it does not occur at temperature.

That is, as a solvent suitable for use in the present invention, for example, 1
Volume ratio of chloronaphthalene and dimethyl sulfoxide 1:
Any solvent that satisfies the above conditions, such as a solvent mixed in a ratio of 1 to 1: 2, or amyl alcohol or dimethylformamide, can be used. The amount of solvent used is calculated by the formula [2]
And an amount that dissolves all of the compound represented by the formula [3] is preferable, but it may be an amount that dissolves a part of both.

The reaction temperature is preferably 100 ° C. or lower, more preferably 70
To 100 ° C., but is not limited to this range, and can be appropriately selected depending on the type of the object.
The reaction time varies depending on the reaction temperature and the dissolved state of the raw materials, but the end point of the reaction can be judged by the time when the color of the compound represented by the formula [2] disappears.

The method for measuring the nonlinear optical properties of the compound of the formula [1] used in the present invention is as follows. A thin film of this compound is formed on a quartz substrate.

The thickness of the thin film is preferably 1 μm or less, but is not necessarily limited to this range.

When the obtained thin film sample is irradiated with a laser while changing the incident angle, the intensity change of the emitted third harmonic wave forms a pattern called maker fringe. From this fringe pattern, a third-order nonlinear susceptibility χ ⁽³⁾ that quantitatively expresses the nonlinear optical effect is obtained.

Examples of the method of forming the thin film include casting method, spin coating method, vapor deposition method and the like. In the casting method, the spin coating method and the like, the solution of the phthalocyanine derivative of the present invention is used. Examples of solvents suitable for use include the following.

Aliphatic saturated hydrocarbons such as N-hexane, N-heptane, N-octane and cyclohexane, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, and esters such as ethyl acetate, butyl acetate, methyl cellosolve and ethyl cellosolve , Alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol and N-butyl alcohol; aromatic hydrocarbons such as benzene, toluene and xylene; chlorinated aromatic hydrocarbons such as chlorobenzene and orthodichlorobenzene , Chloroform, dichloromethane, tetrachlorethylene and other chlorinated aliphatic hydrocarbons.

Hereinafter, (A) to (L) are illustrated as examples of the phthalocyanine derivative of the formula [1] that can be used in the present invention.

(Examples) The present invention will be described in more detail based on the following examples, but the present invention is not limited to these examples.
In each example, "part" means "part by weight" unless otherwise specified.

Example 1 5.8 parts of the following compound (a) in a mixture of 117 parts of dimethyl sulfoxide and 64 parts of 1-chloronaphthalene, And 1.5 parts of isoindoline were added, and the mixture was stirred at 80 ° C. for 4 hours. After cooling to room temperature, the precipitate formed is filtered off,
It was washed with dimethyl sulfoxide, methanol and acetone and then dried to obtain 4.6 parts of the compound (A).

Next, a thin film of the compound (A) having a thickness of 0.58 μm was formed on a quartz substrate having a length of 1 cm and a width of 3 cm by an evaporation method.

The fundamental wave of the ND: YAG laser is irradiated with light with a wavelength of 1909 nm obtained by wavelength conversion with a Raman cell filled with hydrogen, while changing the incident angle from -40 degrees to 40 degrees to this thin film sample, The maker fringe was obtained by measuring the intensity of the third harmonic.

From this fringe pattern, the third-order nonlinear susceptibility χ ⁽³⁾
The value of 2.1X10 ^-10 esu was obtained.

Example 2 10.1 parts of the following compound (b) in a mixture of 147 parts of dimethyl sulfoxide and 81 parts of 1-chloronaphthalene, And 2.9 parts of 5-octylthio-1,3-diiminoisoindoline were added, and the mixture was stirred at 75 ° C. for 5 hours. After cooling to room temperature, 228 parts of methanol was added, the precipitate formed was filtered, washed with dimethysulfoxide and methanol, and then dried to obtain 9.2 parts of compound (B).

Next, using a column chromatography with silica gel as a packing material, the compound (B) was purified by developing with chloroform and allowing it to flow out.

A chloroform solution of the compound (B) was applied onto a quartz substrate having a length of 1 cm and a width of 3 cm by a spin coating method to form a thin film having a thickness of 0.37 μm.

The fundamental wave of the ND: YAG laser is irradiated with light with a wavelength of 1909 nm obtained by wavelength conversion with a Raman cell filled with hydrogen, while changing the incident angle from -40 degrees to 40 degrees to this thin film sample, The maker fringe was obtained by measuring the intensity of the third harmonic.

From this fringe pattern, the third-order nonlinear susceptibility χ ⁽³⁾
The value of 8.1X10 ^-10 esu was obtained.

Example 3 In a mixture of 141 parts of dimethyl sulfoxide and 76 parts of 1-chloronaphthalene, 7.9 parts of the following compound (c), Then, 4.3 parts of 5,6-bis (octylthio) -1,3-diiminoisoindoline was added, and the mixture was stirred at 80 ° C for 5 hours.

After cooling to room temperature, 217 parts of methanol was added, the resulting precipitate was filtered, washed with dimethylsulfoxide and methanol, and then dried to obtain 8.3 parts of compound (C).

Next, by using column chromatography using silica gel as a packing material, the compound (C) was purified by developing with chloroform and allowing it to flow out.

A chloroform solution of the compound (C) was applied onto a quartz substrate having a length of 1 cm and a width of 3 cm by a spin coating method to form a thin film having a thickness of 0.27 μm.

The fundamental wave of the ND: YAG laser is irradiated with light with a wavelength of 1909 nm obtained by wavelength conversion with a Raman cell filled with hydrogen, while changing the incident angle from -40 degrees to 40 degrees to this thin film sample, The maker fringe was obtained by measuring the intensity of the third harmonic.

From this fringe pattern, the third-order nonlinear susceptibility χ ⁽³⁾
The value of 5.2X10 ^-10 esu was obtained.

Examples 4 to 12 Compounds (D) to (L) were prepared in the same manner as in Example 1 except that the compounds of formula [2] and formula [3] corresponding to compounds (D) to (L) were used. Manufactured.

Table 1 shows the structure and amount of the starting compound used in the production and the amount of the obtained phthalocyanine derivative.

These compounds (D) to (L) were formed into thin films having the thicknesses shown in Table 2 on a quartz substrate by the same operation as in Example 1, and the third-order nonlinear susceptibility was obtained by the same method as in Example 1. χ ⁽³⁾ was measured.

 Table 2 shows the measurement results.

(Effect of the Invention) According to the present invention, as compared with the conventional organic nonlinear optical material,
An organic nonlinear optical material having a third-order nonlinear susceptibility equal to or higher than these is provided.

According to the present invention, an organic nonlinear optical material that is extremely stable in air and has heat resistance stability is provided, which is easy to store and handle.

According to the present invention, there is provided an organic nonlinear optical material in which a thin film can be easily formed and the film thickness can be easily controlled.

Further, according to the present invention, there is provided an organic nonlinear optical material applicable as various elements in the field of optoelectronics, as a nonlinear optical material having a high response speed.

Claims (1)

(57) [Claims] 1. An organic nonlinear optical material containing, as a component, at least one phthalocyanine derivative represented by the following formula [1]. Equation [1] [In the formula, R ^{1 to} R ²² each independently have a hydrogen atom, a halogen atom, a cyano group, a nitro group, a carboxy group, a sulfo group, an optionally substituted aliphatic hydrocarbon group, or a substituent Aromatic hydrocarbon group, optionally substituted aromatic heterocyclic group, -OR ²³ , -SR ²⁴ , -NR ²⁵ R ²⁶ , -SO ₂ NR ²⁷ R ²⁸ , -C
ONR ²⁹ R ³⁰ , -NHCOR ³¹ , -CO ₂ R ³² , -N = NR ³³ , -X (CH ₂ CH
₂ Y) Represents zR ³⁴ . R ^{23 to} R ³⁴ are a hydrogen atom, an aliphatic hydrocarbon group which may have a substituent, an aromatic hydrocarbon group which may have a substituent, an aromatic heterocyclic group which may have a substituent Represents X and Y each independently represent an oxygen atom or a sulfur atom, and z represents a positive integer. ]