JP2005092074A - Two-photon absorption optical recording material and method for two-photon absorption optical recording - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional optical recording material as a high-density and high-capacity recording medium which achieves ultrahigh density and ultrahigh capacity recording several tens or hundreds times of those of a conventional two-dimensional recording medium, and to provide a recording method. <P>SOLUTION: The method for two-photon absorption optical recording is carried out by inducing changes in the orientation of a compound having a specific birefringent index by two-photon absorption and fixing the compound as it is by chemical reaction to record as modulation of the refractive index by a unrewritable method. The two-photon absorption optical recording material by the unrewritable method contains at least a low molecular weight liquid crystalline compound having a polymerizable group, a photoreactive compound performing two-photon absorption and a polymerization initiator. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a material that exhibits a nonlinear optical effect. In particular, it causes an orientation change of a compound having an intrinsic birefringence due to two-photon absorption and is fixed as it is by a chemical reaction, so that the refractive index can be modulated by a method that cannot be rewritten. A two-photon absorption optical recording method characterized by recording, and a method having at least a low-molecular liquid crystal compound having a polymerizable group, a two-photon absorption compound, a photoreactive compound, and a polymerization initiator, and not rewritable The present invention relates to a two-photon absorption optical recording material and a two-photon absorption optical recording method.

  In general, the nonlinear optical effect is a non-linear optical response proportional to the square of the applied photoelectric field, the third power or more, and a second-order nonlinear optical effect proportional to the square of the applied photoelectric field. For example, second harmonic generation (SHG), optical rectification, photorefractive effect, Pockels effect, parametric amplification, parametric oscillation, optical sum frequency mixing, and optical difference frequency mixing are known. The third-order nonlinear optical effect proportional to the cube of the applied photoelectric field includes third harmonic generation (THG), optical Kerr effect, self-induced refractive index change, two-photon absorption, and the like.

  Many inorganic materials have been found so far as nonlinear optical materials exhibiting these nonlinear optical effects. However, inorganic materials are very difficult to put into practical use because so-called molecular design for optimizing desired nonlinear optical characteristics and various physical properties necessary for device fabrication is difficult. On the other hand, organic compounds can be optimized not only for the desired nonlinear optical properties by molecular design, but also for other physical properties, so they are highly practical and attract attention as promising nonlinear optical materials. Collecting.

  In recent years, the third-order nonlinear optical effect has attracted attention among the nonlinear optical characteristics of organic compounds, and among these, non-resonant two-photon absorption has attracted attention. Two-photon absorption is a phenomenon in which a compound is excited by simultaneously absorbing two photons, and the case where two-photon absorption occurs in an energy region where there is no (linear) absorption band of the compound is called non-resonant two-photon absorption. . In the following description, two-photon absorption refers to non-resonant two-photon absorption even if not specified.

By the way, the efficiency of non-resonant two-photon absorption is proportional to the square of the applied photoelectric field (square characteristic of two-photon absorption). For this reason, when a two-dimensional plane is irradiated with a laser, two-photon absorption occurs only at a position where the electric field strength is high in the central portion of the laser spot, and two-photon absorption is completely absent in a portion where the electric field strength is weak in the peripheral portion. Does not happen. On the other hand, in the three-dimensional space, two-photon absorption occurs only in the region where the electric field strength at the focal point where the laser light is collected by the lens is large, and no two-photon absorption occurs in the region outside the focal point because the electric field strength is weak. . Compared with linear absorption where excitation occurs at all positions in proportion to the intensity of the applied photoelectric field, non-resonant two-photon absorption results in excitation at only one point inside the space due to this square characteristic. , The spatial resolution is significantly improved.
Usually, when inducing non-resonant two-photon absorption, a short-pulse laser in the near-infrared region, which is longer than the wavelength region in which the (linear) absorption band of the compound exists and does not have absorption, is often used. The so-called transparent near-infrared light is used, so that the excitation light can reach the inside of the sample without being absorbed or scattered, and because of the square characteristic of non-resonant two-photon absorption, one point inside the sample has an extremely high spatial resolution. Can be excited.
Therefore, if polymerization can be caused by using excitation energy obtained by non-resonant two-photon absorption, polymerization can be caused in an arbitrary place in a three-dimensional space, and a three-dimensional optical recording medium considered as an ultimate high-density recording medium, Application to fine three-dimensional stereolithography materials is also possible.

On the other hand, optical information recording media (optical discs) capable of recording information only once by laser light are known, and write-once CDs (so-called CD-Rs) and write-once DVDs (so-called DVD-Rs). Etc. have been put to practical use.
For example, the typical structure of DVD-R is such that the guide groove (pre-groove) for tracking the irradiated laser beam is narrower than half of CD-R (0.74-0.8 μm). Further, a recording layer made of a dye is formed on a transparent disk-shaped substrate, and a light reflecting layer is usually formed on the recording layer, and a protective layer is further formed if necessary.
Information is recorded on the DVD-R by irradiating with visible laser light (usually in the range of 630 nm to 680 nm), and the irradiated portion of the recording layer absorbs the light and the temperature rises locally. A change (eg, pit generation) occurs and changes its optical properties. On the other hand, reading (reproduction) of information is also performed by irradiating laser light having the same wavelength as the recording laser light, and the part where the optical characteristics of the recording layer have changed (recorded part) and the part that has not changed (unrecorded) Information is reproduced by detecting the difference in reflectance from (part). This difference in reflectivity is based on so-called “refractive index modulation”. The greater the difference in refractive index between the recorded portion and the non-recorded portion, the greater the ratio of the reflectance of light, that is, the S / N ratio of reproduction. Larger and preferable.

Recently, networks such as the Internet and high-definition TV are rapidly spreading. In addition, HDTV (High Definition Television) will soon be broadcast, and there is an increasing demand for a large-capacity recording medium for recording image information of 50 GB or more inexpensively and easily for consumer use.
Furthermore, for business use such as computer backup use and broadcast backup use, an optical recording medium capable of recording large-capacity information of about 1 TB or more at high speed and at low cost is required.
Under such circumstances, a conventional two-dimensional optical recording medium such as a DVD-R is about 25 GB at most even if the recording / reproducing wavelength is shortened on the physical principle, and is sufficiently large enough to meet future demands. It cannot be said that capacity can be expected.

  Under such circumstances, a three-dimensional optical recording medium has attracted attention as an ultimate high-density, high-capacity recording medium. Three-dimensional optical recording media can be recorded in dozens or hundreds of layers in the three-dimensional (film thickness) direction, resulting in tens or hundreds of times the ultra-high density and ultra-high capacity recording of conventional two-dimensional recording media. That is what we are trying to achieve. In order to provide a three-dimensional optical recording medium, it is necessary to be able to access and write at an arbitrary place in the three-dimensional (film thickness) direction. As a means for this, a method using a two-photon absorption material and holography (interference) There is a method of using.

In a three-dimensional optical recording medium using a two-photon absorption material, so-called bit recording is possible over tens or hundreds of times based on the physical principle described above, and higher density recording is possible. It can be said to be the ultimate high-density, high-capacity optical recording medium.
As a three-dimensional optical recording medium using a two-photon absorption material, a method of reading with fluorescence using a fluorescent substance for recording and reproduction [see Patent Document 1], [See Patent Document 2], absorption or fluorescence using a photochromic compound [Patent Document 3], [Patent Document 4], and the like have been proposed, but none of them presents a specific two-photon absorption material, and two-photon absorption is presented abstractly. Examples of the compound also use a two-photon absorption compound with extremely low two-photon absorption efficiency, and further have problems in nondestructive reading, long-term storage stability, S / N ratio of reproduction, etc., and practicality as an optical recording medium. It cannot be said that it is a certain method.
On the other hand, [Patent Document 5] discloses a three-dimensional optical recording medium using a two-photon absorption alignment change of a polymer-dispersed nematic liquid crystal material. However, the two-photon absorption efficiency is low, nondestructive reading, recording There is a problem with long-term storage, and it cannot be said that this is a practical method as an optical recording medium.
In particular, in terms of non-destructive reading, long-term storage stability of recording, etc., it is preferable to reproduce by changing the reflectance (refractive index) using an irreversible material. Specifically, a two-photon absorption material having such a function is specifically described. There were no disclosed examples.

  [Patent Document 6] and [Patent Document 7] disclose a recording apparatus, a reproducing apparatus, a reading method, and the like that perform three-dimensional recording by refractive index modulation, but a two-photon absorption optical recording material is disclosed. There is no specific description of the method used.

Special table 2001-524245 specification Special table 2000-512061 specification Special table 2001-522119 specification Special table 2001-508221 specification International Publication No. 2002/47090 Pamphlet JP-A-6-28672 JP-A-6-118306

  The object of the present invention is to record the refractive index modulation in a non-rewritable manner by causing an orientation change of a compound having an intrinsic birefringence by two-photon absorption and fixing it as it is by a chemical reaction. It is to provide a photon absorption optical recording method. And a two-photon absorption optical recording material comprising a low-molecular liquid crystalline compound having a polymerizable group, a photoreactive compound that performs two-photon absorption, a polymerization initiator, and a non-rewritable method. That is.

As a result of intensive studies by the inventors, the object of the present invention has been achieved by the following means.
(1) Two-photon absorption light characterized by causing a change in the orientation of a compound having an intrinsic birefringence by two-photon absorption and recording as refractive index modulation in a non-rewritable manner by fixing it by a chemical reaction as it is Recording method.
(2) The two-photon absorption optical recording method as described in (1) above, wherein the compound having an intrinsic birefringence has a polymerizable group and is fixed by polymerization.
(3) The two-photon absorption optical recording method as described in (1) or (2) above, wherein the compound having an intrinsic birefringence is a liquid crystalline compound.
(4) A two-photon absorption optical recording material comprising at least a low-molecular liquid crystalline compound having a polymerizable group, a photoreactive compound that performs two-photon absorption, and a polymerization initiator, and is a system that cannot be rewritten.
(5) A two-photon absorption optical recording material comprising at least a low-molecular liquid crystalline compound having a polymerizable group, a photoreactive compound, a polymerization initiator, and a two-photon absorption compound, and a non-rewritable method.
(6) At least a low-molecular liquid crystalline compound having a polymerizable group, a photoreactive compound, a polymerization initiator, a two-photon absorption compound, and generated by absorption of light during two-photon absorption exposure by the two-photon absorption compound A two-photon absorption optical recording method characterized in that a photoreactive compound is reacted by electron transfer or energy transfer from the excited state and cannot be rewritten.
(7) The two-photon absorption optical recording material as described in (5) above, wherein the two-photon absorption compound is an organic dye.
(8) The two-photon absorption optical recording material according to (5) or (7), wherein the two-photon absorption compound is represented by a methine dye or a phthalocyanine dye.
(9) The two-photon absorption optical recording material as described in (8) above, wherein the two-photon absorption compound is represented by a cyanine dye, a merocyanine dye, an oxonol dye, a phthalocyanine dye or the following general formula (1).
General formula (1)

In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a substituent, and some of R ¹ , R ² , R ³ and R ⁴ are bonded to each other to form a ring. May be formed. n and m each independently represent an integer of 0 to 4, and when n and m are 2 or more, a plurality of R ¹ , R ² , R ³ and R ⁴ may be the same or different. However, n and m are not 0 simultaneously. X ¹ and X ² independently represent an aryl group, a heterocyclic group, or a group represented by General Formula (2).
General formula (2)

In the formula, R ⁵ represents a hydrogen atom or a substituent, R ⁶ represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group, and Z ¹ represents an atomic group forming a 5- or 6-membered ring. .
(10) The two-photon absorption optical recording material according to (9), wherein in the compound represented by the general formula (1), R ¹ and R ³ are linked to form a ring.
(11) The two-photon absorption light as described in (9) above, wherein in the compound represented by the general formula (1), R ¹ and R ³ are linked to form a cyclopentanone ring together with a carbonyl group. Recording material.
(12) In any one of the above (9) to (11), X ¹ and X ² of the compound represented by the general formula (1) are represented by the general formula (2). The two-photon absorption optical recording material described.
(13) In the compound represented by the general formula (1), X ¹ and X ² are represented by the general formula (2), R ⁶ is an alkyl group, and the ring formed by Z ¹ is an indolenine ring. , Azaindolenin ring, pyrazoline ring, benzothiazole ring, thiazole ring, thiazoline ring, benzoxazole ring, oxazole ring, oxazoline ring, benzimidazole ring, thiadiazole ring, quinoline ring The two-photon absorption optical recording material as described in (12) above.
(14) In the compound represented by the general formula (1), X ¹ and X ² are represented by the general formula (2), R ⁶ is an alkyl group, and the ring formed by Z ¹ is an indolenine ring. The two-photon absorption optical recording material as described in (13) above, which is represented by any one of an azaindolenin ring, a benzothiazole ring, a benzoxazole ring and a benzimidazole ring.
(15) The above (9), wherein the cyanine dye is represented by the following general formula (3), the merocyanine dye is represented by the following general formula (4), and the oxonol dye is represented by the general formula (5). The two-photon absorption optical recording material described.

In the general formulas (3) to (5), Za ₁ , Za ₂ and Za ₃ each represent an atomic group forming a 5-membered or 6-membered nitrogen-containing heterocyclic ring, and Za ₄ , Za ₅ and Za ₆ are Each represents a group of atoms forming a 5-membered or 6-membered ring. Ra ₁ , Ra ₂ and Ra ₃ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or a heterocyclic group.
Ma _{1 to} Ma ₁₄ each independently represent a methine group, may have a substituent, and may form a ring with other methine groups. na ¹ , na ² and na ³ are each 0 or 1, and ka ¹ and ka ³ each represents an integer of 0 to 3. When ka ¹ is 2 or more, the plurality of Ma ₃ and Ma ₄ may be the same or different, and when ka ³ is 2 or more, the plurality of Ma ₁₂ and Ma ₁₃ may be the same or different. ka ² represents an integer of 0 to 8, and when ka ² is 2 or more, the plurality of Ma ₁₀ and Ma ₁₁ may be the same or different.
CI represents an ion for neutralizing the electric charge, and y represents a number necessary for neutralizing the electric charge.
(16) The two-photon absorption optical recording according to any one of (5) and (7) to (15) above, wherein the two-photon absorption compound has at least one hydrogen bonding group. material.
(17) The two-photon absorption optical recording material as described in (16) above, wherein the hydrogen bonding group is —COOH group or —CONH ₂ group.
(18) The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (17), wherein the photoreactive compound is a photoisomerizable compound. .
(19) The photoreactive compound is an azobenzene compound, stilbene compound, spiropyran compound, spirooxazine compound, diarylethene compound, fulgide compound, fulgimide compound, cinnamic acid compound, coumarin compound, or chalcone compound. The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (18), which is any one of the above.
(20) The two-photon absorption optical recording material as described in (19) above, wherein the photoreactive compound is an azobenzene compound.
(21) The above (4), (18) to (18), wherein the system has at least a low molecular liquid crystal compound having a polymerizable group, a photoreactive compound, a polymerization initiator, and a binder and cannot be rewritten. (20) The two-photon absorption optical recording material according to (20).
(22) The above (5), which has at least a low molecular liquid crystalline compound having a polymerizable group, a photoreactive compound, a polymerization initiator, a two-photon absorption compound, and a binder, and is a system that cannot be rewritten. The two-photon absorption optical recording material according to any one of (7) to (17) or (21) above.
(23) The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (22) above, wherein the photoreactive compound is a low molecular compound.
(24) The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (22) above, wherein the photoreactive compound is a polymer compound.
(25) The two-photon absorption optical recording material according to (24), wherein the photoreactive compound in (24) is a polymer compound in which a photoreactive site is pendant.
(26) The two-photon absorption optical recording material as described in (21) or (22) above, wherein the binder is a polymer compound in which a photoreactive compound is pendant.
(27) In the above (4), the low molecular liquid crystal compound having a polymerizable group is any of a nematic liquid crystal compound, a smectic liquid crystal compound, a discotic nematic liquid crystal compound, a discotic liquid crystal compound, and a cholesteric liquid crystal compound. The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (26) above, wherein
(28) The two-photon absorption light as described in (27) above, wherein the low molecular liquid crystalline compound having a polymerizable group is any one of a nematic liquid crystalline compound, a discotic nematic liquid crystalline compound, and a cholesteric liquid crystalline compound. Recording material.
(29) The two-photon absorption optical recording material as described in (28) above, wherein the low molecular liquid crystalline compound having a polymerizable group is a nematic liquid crystalline compound.
(30) The polymerizable group in (4) above is an acryl group, a methacryl group, a styryl group, a vinyl group, an oxirane group, an oxolane group, or a vinyl ether group, (4) to (5), ( The two-photon absorption optical recording material according to any one of 7) to (29).
(31) The above (4) to (5) and (7) to (7) above, wherein the polymerization initiator of (4) is any of a radical polymerization initiator, a cationic polymerization initiator, and an anionic polymerization initiator. The two-photon absorption optical recording material according to any one of (20).
(32) Polymerization initiator is ketone, organic peroxide, bisimidazole, trihalomethyl-substituted triazine, diazonium salt, diaryl iodonium salt, sulfonium salt, organic borate, diaryl iodonium organic boron complex, sulfonium organic boron complex, metal arene The two-photon absorption optical recording material as described in (31) above, which is a radical polymerization initiator of any of the complexes.
(33) The polymerization initiator is a cationic polymerization initiator (acid generator) of any of trihalomethyl-substituted triazines, diazonium salts, diaryliodonium salts, sulfonium salts, metal arene complexes, and sulfonic acid esters. The two-photon absorption optical recording material according to the above (32).
(34) The two-photon absorption optical recording material as described in (33) above, wherein at least one base generator is represented by the following general formulas (31-1) to (31-4).

In formula (31-1) ~ (31-4), R 201, R 202, R 213, R 214, R 215 are each independently a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a hetero R ₂₀₁ , R ₂₀₂ may be connected to each other to form a ring, and R ₂₁₃ , R ₂₁₄ , R ₂₁₅ may be connected to each other to form a ring. R ₂₀₃ , R ₂₀₆ , R ₂₀₇ and R ₂₀₉ each independently represent a substituent, and R ₂₀₄ , R ₂₀₅ , R ₂₀₈ , R ₂₁₀ and R ₂₁₁ each independently represents a hydrogen atom or a substituent, R ₂₁₀ , R ₂₁₁ may be linked to each other to form a ring. R ₂₁₆ , R ₂₁₇ , R ₂₁₈ and R ₂₁₉ each independently represents an alkyl group or an aryl group, and R ₂₁₂ represents an aryl group or a heterocyclic group. n201 represents an integer of 0 or 1, and n202 to n204 each independently represents an integer of 0 to 5.
(35) The two-photon absorption optical recording material as described in (34) above, wherein in the general formulas (31-1) and (31-2), n201 is 1.
(36) In the general formula (31-1), R ₂₀₃ is any one of a nitro group substituted at the 2-position or the 2,6-position, or an alkoxy group substituted at the 3,5-position. (34) or the two-photon absorption optical recording material according to the above (35).
(37) The two-photon absorption optical recording material as described in (34) or (35) above, wherein in formula (31-2), R ₂₀₆ is an alkoxy group substituted at the 3,5-position.
(38) When performing optical recording by two-photon absorption on the two-photon absorption optical recording material having the liquid crystalline compound described in the above (4) to (5) and (7) to (37), the liquid crystalline compound is in a liquid crystal state. The two-photon absorption optical recording method according to (1) to (3) or (6) above, wherein two-photon absorption optical recording is performed at a temperature of
(39) Two-photon absorption optical recording, wherein optical recording is performed by two-photon absorption while heating the two-photon absorption optical recording material described in (4) to (5) and (7) to (37). Method.
(40) When performing recording using the two-photon absorption optical recording material described in the above (4) to (5) and (7) to (37), after the two-photon absorption exposure, the whole surface exposure, heat treatment or the The two-photon absorption optical recording method according to any one of (1) to (3), (6), and (38) to (39), wherein both are performed.
(41) The two-photon absorption recording material described in (4) to (5) and (7) to (37) above has a wavelength longer than the linear absorption band of the two-photon absorption compound and does not have linear absorption. Using the two-photon absorption induced by irradiating the laser beam, the change in the orientation of the compound having an intrinsic birefringence is caused, and is fixed as it is by a chemical reaction. A two-photon absorption optical recording method characterized by recording.
(42) A three-dimensional optical recording method using the two-photon absorption optical recording method according to any one of (1) to (3), (6), and (38) to (41).
(43) An optical recording medium using the two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (37).
(44) A three-dimensional optical recording medium using the two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (37).
(45) The two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (37) is stored in a light-shielding cartridge at the time of storage. Optical recording medium.
(46) An optical material comprising the two-photon absorption optical recording material according to any one of (4) to (5) and (7) to (37).
(47) An optical material manufacturing method using the two-photon absorption optical recording method according to any one of (1) to (3), (6), and (38) to (41).

  By using the two-photon absorption optical recording material of the present invention, refractive index modulation recording can be performed based on the orientation change due to two-photon absorption, and further, the three-dimensional optical recording can be fixed as it is and cannot be rewritten and has good storage stability. Application to media is expected.

Hereinafter, the best mode for carrying out the present invention of the two-photon absorption optical recording method and the two-photon absorption optical recording material will be described in detail.
The two-photon absorption optical recording method of the present invention causes interference fringe recording by refractive index modulation in a non-rewritable manner by causing an orientation change of a compound having an intrinsic birefringence by two-photon absorption and fixing it as it is by a chemical reaction. This is a two-photon absorption optical recording method.

  Here, the non-rewritable method is a method of recording by irreversible reaction, and indicates a method in which once recorded data can be stored without being rewritten even if it is overwritten and recorded. Therefore, it is suitable for storing important data that requires long-term storage. However, of course, it is possible to newly record in an area that has not been recorded yet. In that sense, it is generally called “write-once type” or “write-once type”.

The compound having an intrinsic birefringence preferably represents a compound having a different refractive index (n _e ) in the major axis direction and a refractive index (n _o ) in the minor axis direction which are inherent to the molecule. (Addition) Here, the intrinsic birefringence represents the intrinsic birefringence of the molecule and can be obtained from the bulk birefringence of the solid, liquid crystal state, etc., but can also be obtained by molecular orbital calculation. . The two-photon absorption optical recording method of the present invention is a method of performing recording by refractive index modulation by controlling the orientation of a compound having a birefringence by two-photon absorption, so that the intrinsic refraction of a compound having an intrinsic birefringence is achieved. rate anisotropy Δn = | n _e -n _o | as a large preferably, is preferably 0.01 or more, more preferably 0.05 or more, and most preferably 0.1 or more.
Therefore, the compound having an intrinsic birefringence of the present invention is preferably a rod-like compound having a long conjugation in the long axis direction of the molecule.

  The compound having an intrinsic birefringence of the present invention is preferably a so-called dichroic compound (pigment) or a liquid crystal compound, more preferably a liquid crystal compound, still more preferably a low molecular liquid crystal compound, and most preferably. Is a low-molecular liquid crystalline compound having at least two or more rings in the core.

The compound having an intrinsic birefringence of the present invention, preferably a liquid crystal compound, is preferably fixed as it is after the orientation change by two-photon absorption. Therefore, the compound having an intrinsic birefringence of the present invention, preferably a liquid crystalline compound, preferably has a reactive group and can be fixed in its orientation upon reaction in two-photon absorption exposure or in subsequent processing. . As the chemical reaction, an irreversible reaction is preferable, and an addition reaction, a ring-opening addition reaction, a condensation reaction, a ring-opening condensation reaction, a cyclization reaction, a nucleophilic reaction, an electrophilic reaction, a radical reaction, a complexing reaction, and the like are preferable.
In the present invention, the chemical reaction is more preferably a polymerization reaction. Examples of the polymerization reaction include an addition polymerization reaction, a ring-opening addition polymerization reaction, a condensation polymerization reaction, a ring-opening condensation polymerization reaction, a complexing reaction, and the like, more preferably an addition polymerization reaction or a ring-opening addition polymerization reaction. At that time, it is preferable that any one of radical polymerization reaction, cationic polymerization reaction and anionic polymerization reaction occurs.
Accordingly, the compound having an intrinsic birefringence of the present invention, preferably a liquid crystal compound, more preferably a low molecular liquid crystal compound, more preferably has a polymerizable group, and more preferably is immobilized by a polymerization reaction. In this case, the polymerizable group is preferably an acryl group, a methacryl group, a styryl group, a vinyl group, an oxirane group, an oxolane group, or a vinyl ether group.

The liquid crystalline compound of the present invention is preferably a nematic liquid crystalline compound, a smectic liquid crystalline compound, a discotic nematic liquid crystalline compound, a discotic liquid crystalline compound, or a cholesteric liquid crystalline compound. More preferably, it is either a discotic nematic liquid crystalline compound or a cholesteric liquid crystalline compound, and more preferably a nematic liquid crystalline compound.
Therefore, the liquid crystalline compound of the present invention is more preferably a low molecular liquid crystalline compound having a polymerizable group and having the above phase.

  When performing optical recording by two-photon absorption on the two-photon absorption optical recording material having the liquid crystalline compound of the present invention, it is preferable to perform two-photon absorption optical recording at a temperature at which the liquid crystalline compound takes a liquid crystal state. When the temperature is higher than room temperature, it is also preferable to perform two-photon absorption optical recording while heating the two-photon absorption optical recording material.

The two-photon absorption optical recording material of the present invention preferably has at least a low molecular liquid crystalline compound having a polymerizable group, a photoreactive compound, and a polymerization initiator.
Here, the photoreactive compound of the present invention can change the structure by reacting with light, and as a result, the refractive index is modulated by changing the alignment state of the liquid crystalline compound, preferably a low molecular liquid crystalline compound having a polymerizable group. Represents a compound that can be
Although the photoreactive compound of the present invention may perform two-photon absorption by itself, since the two-photon absorption efficiency of the photoreactive compound itself is low, a two-photon absorption compound different from the photoreactive compound absorbs two photons. The photoreactive compound reacts and changes its structure by electron transfer or energy transfer from the excited state of the two-photon absorption compound generated by absorption to the photoreactive compound, resulting in a liquid crystalline compound, preferably having a polymerizable group The method of modulating the refractive index by changing the alignment state of the low-molecular liquid crystalline compound is more preferable in terms of higher efficiency.

Preferably, the photoreaction caused by the photoreactive compound is an isomerization reaction, bimolecular cyclization reaction, ring closure reaction, ring opening reaction, addition reaction, elimination reaction, condensation reaction, solvent addition reaction, nucleophilic reaction, electrophilic reaction. , Radical reaction, complexing reaction, etc., preferably isomerization reaction, bimolecular cyclization reaction, ring closure reaction, ring opening reaction.
Preferred examples of the photoreactive compound that undergoes isomerization reaction include azobenzene compounds and stilbene compounds, and preferred examples of the compound that undergoes bimolecular cyclization reaction include cinnamic acid compounds, coumarin compounds, and chalcone compounds. Preferred compounds that undergo a ring-opening reaction include spiropyran compounds and spirooxazine compounds, and preferred compounds that undergo a ring-closing reaction include diarylethene compounds, fulgide compounds, and fulgimide compounds.
As the photoreactive compound of the present invention, a photoisomerizable compound is more preferable, and an azobenzene compound is more preferable.
The photoisomerization compound may be a low molecular compound or a high molecular compound, but in the case of a high molecular compound, a high molecular compound in which a photoreactive site is pendant is more preferable.

As described above, the two-photon absorption optical recording material of the present invention preferably further contains a two-photon absorption compound in addition to the photoreactive compound. At that time, it is preferable to react the photoreactive compound by electron transfer or energy transfer from the excited state of the two-photon absorption compound generated by the two-photon absorption compound generated by absorbing the two photons.

The two-photon absorption optical recording material of the present invention preferably contains a polymerization initiator. The polymerization initiator is preferably a radical polymerization initiator that generates radicals, a cationic polymerization initiator that generates acids, or an anionic polymerization initiator that generates bases.
The polymerization initiator of the present invention preferably generates radicals, acids or bases from the excited state of the two-photon absorption compound or photoreactive compound by energy transfer or electron transfer, or by direct excitation.

In the two-photon absorption optical recording material of the present invention, it is also preferable to use a binder (polymer matrix compound) in addition to a low-molecular liquid crystalline compound, a photoreactive compound, a polymerization initiator, and a two-photon absorption compound. The binder is used for the purpose of increasing the film strength and improving the film forming property. In addition, when the photoreactive compound is a polymer compound, particularly when the photoreactive compound is a polymer compound pendant with a photoreactive site, it is preferable that the photoreactive compound also serves as a binder.
Furthermore, in the two-photon absorption optical recording material of the present invention, additives such as a polymerizable monomer, a polymerizable oligomer, a crosslinking agent, a heat stabilizer, a plasticizer, and a solvent are used as necessary.

  The two-photon absorption optical recording material of the present invention is preferably not subjected to wet processing after two-photon absorption exposure.

  Note that the refractive index modulation during recording is preferably 0.001 to 0.5, and more preferably 0.005 to 0.3.

A laser is preferably used for recording by two-photon absorption. The light used in the present invention is preferably ultraviolet light having a wavelength of 200 to 2000 nm, visible light, or infrared light, more preferably ultraviolet light having a wavelength of 300 to 1000 nm, visible light, or infrared light, and further preferably. Is 400 to 800 nm visible or infrared light.
The laser that can be used is not particularly limited, but specifically, it is also used in a solid laser such as Ti-sapphire having an oscillation wavelength near a central wavelength of 1000 nm, a fiber laser, a CD-R having an oscillation wavelength near 780 nm, or the like. Preferred are semiconductor lasers, solid lasers, fiber lasers, semiconductor lasers used in DVD-R having an oscillation wavelength in the range of 620 to 680 nm, solid lasers, GaN lasers having an oscillation wavelength in the vicinity of 400 to 415 nm, etc. Can be used.
In addition, a solid SHG laser such as a YAG / SHG laser having an oscillation wavelength in the visible light region, a semiconductor SHG laser, or the like can be preferably used.
The laser used in the present invention may be a pulsed laser or a CW laser.

In the two-photon absorption optical recording material of the present invention, after the two-photon absorption exposure, a fixing step may be performed by light, heat, or both.
In the case of photofixing, the entire surface of the two-photon absorption optical recording material is irradiated with ultraviolet light or visible light (non-interference exposure). Preferred examples of the light source used include a visible light laser, an ultraviolet light laser, a carbon arc, a high-pressure mercury lamp, a xenon lamp, a metal halide lamp, a fluorescent lamp, a tungsten lamp, an LED, and an organic EL.
In the case of thermal fixing, the fixing step is preferably performed at 40 ° C to 160 ° C, more preferably 60 ° C to 130 ° C.
When both photofixing and heat fixing are performed, light and heat may be applied simultaneously, or light and heat may be added separately.

  Note that the refractive index modulation during recording is preferably 0.001 to 0.5, and more preferably 0.005 to 0.3.

Here, in the two-photon absorption optical recording material of the present invention, the reproduction is performed by irradiating the recording material with light and detecting the difference in the light reflectance based on the difference in refractive index between the recording part and the non-recording part. The two-photon absorption optical recording / reproducing method is preferable.
At that time, the two-photon absorption optical recording in which the wavelength of light irradiated when recording by two-photon absorption is performed in the first step is the same as the wavelength of light irradiated to detect a difference in reflectance during reproduction. A regeneration method is more preferred.
That is, the light used for reproduction is also preferably laser light, and it is more preferable to reproduce using the same laser as that used for recording, although the power or pulse shape is the same or different.

  In the two-photon absorption optical recording material of the present invention, the size of the reaction part or coloring part generated by recording is preferably in the range of 10 nm to 100 μm, more preferably in the range of 50 nm to 5 μm, and 50 nm. More preferably, it is in the range of ˜2 μm.

  In the two-photon absorption optical recording method of the present invention and the two-photon absorption optical recording material capable of such recording, either recording by two-photon absorption or subsequent fixing by light irradiation, heat application, or both It is preferable to decompose and fix the two-photon absorption compound and the photoreactive compound by non-destructive regeneration and further improvement of storage stability.

  The two-photon absorption compound and the two-photon absorption optical recording material of the present invention may perform multiphoton absorption of three or more photons.

The two-photon absorption optical recording material and recording / reproducing method of the present invention include an optical recording medium such as DVD-R and DVD-BL (BR), a near-field optical recording medium, a three-dimensional optical recording medium, an antireflection film, and a light extraction. It is preferably used for optical materials such as a rate improving film, a reflectance improving film, and a polarizing film.
The two-photon absorption optical recording material and the recording / reproducing method of the present invention are more preferably a two-photon absorption three-dimensional optical recording method and a two-photon absorption three-dimensional optical recording material capable of such recording. In this case, it is more preferable to use it for a three-dimensional optical recording medium.

  When the two-photon absorption optical recording material of the present invention is used for an optical recording medium, the two-photon absorption optical recording material is preferably stored in a light shielding cartridge during storage.

Hereinafter, each component of the two-photon absorption optical recording material of the present invention will be described in detail.
In the present invention, when a specific moiety is referred to as a “group”, unless otherwise specified, it may be substituted with one or more (up to the maximum possible) substituents. It means that it is not necessary. For example, “alkyl group” means a substituted or unsubstituted alkyl group. In addition, the substituent that can be used in the compound in the present invention may be any substituent.
In the present invention, when a specific moiety is referred to as “ring”, or when “group” includes “ring”, it may be monocyclic or condensed unless otherwise specified. May not be substituted.
For example, the “aryl group” may be a phenyl group, a naphthyl group, or a substituted phenyl group.

  First, the liquid crystal compound of the present invention will be described.

As described above, the liquid crystalline compound of the present invention is preferably a low molecular liquid crystalline compound, more preferably a low molecular liquid crystalline compound having at least two or more rings in the core portion.
Furthermore, the liquid crystalline compound of the present invention preferably has a reactive group, and more preferably has a polymerizable group. Therefore, the liquid crystalline compound of the present invention is more preferably a low molecular liquid crystalline compound having a polymerizable group.

  The low molecular liquid crystalline compound having a polymerizable group of the present invention is preferably represented by the following general formula (32).

In the general formula (32), L ₁₀₁ represents a liquid crystalline core part, and examples of the liquid crystalline core part include Mitsuji Okano and Keisuke Kobayashi, “Liquid Crystal Fundamentals”, Baifukan, 1985, “Chemical Review No. 22”. , Liquid Crystal Chemistry ", 1994, etc., but in the present invention, it is preferably represented by any of the following. In the figure, a line extending from the liquid crystalline core portion represents a substitution position. However, a substituent may be substituted at a place other than the line indicated.

  The liquid crystalline core portion has an alkyl group that promotes the appearance of liquid crystalline properties (preferably 1 to 20 carbon atoms (hereinafter referred to as C number), for example, methyl, ethyl, n-propyl, n-butyl, n-pentyl. , N-hexyl, benzyl), alkenyl group (preferably C 2-20, such as vinyl, allyl, 2-butenyl, 1,3-butadienyl), alkynyl group (preferably C 2-20, such as ethynyl, 2 -Propynyl, 1,3-butadiynyl, 2-phenylethynyl), cyano group, nitro group, halogen atom (for example, F, CL, BR, I), alkoxy group (preferably having 1 to 20 carbon atoms, for example, methoxy, ethoxy ), An acylamino group (preferably C 1-20, such as acetylamino, benzoylamino), an amino group (preferably C 1-20, such as dimethylamino) , Diethylamino, dibutylamino) and the like may be substituted.

  The liquid crystalline core of the present invention is preferably one of nematic liquid crystalline, smectic liquid crystalline, discotic nematic liquid crystalline, discotic liquid crystalline, cholesteric liquid crystalline, nematic liquid crystalline, discotic nematic liquid crystalline. Or cholesteric liquid crystallinity, more preferably nematic liquid crystallinity.

In the general formula (32), R ₁₀₁ represents a polymerizable group or a hydrogen atom, preferably an acrylic group, a methacryl group, a styryl group, a vinyl group, an oxirane group, an oxolane group, a vinyl ether group, or a hydrogen atom, more preferably An acryl group, a methacryl group, an oxirane group, or an oxolane group is represented.

In the general formula (32), L ₁₀₂ represents a linking group, preferably L ₁₀₂ represents an alkylene group (preferably having a C number of 1 to 20, for example, methylene, ethylene, propylene, butylene, pentylene, hexylene, octylene), an alkenylene group ( Preferably C number 2-20, for example ethenylene, propenylene, butenylene, butadienylene), alkynylene group (preferably C number 2-20, for example ethynylene, butadienylene), arylene group (preferably C number 6-26, for example 1, 4 -Phenylene, 1,4-naphthylene, 2,6-naphthylene), a heterylene group (preferably having 1 to 20 carbon atoms, such as 2,5-thienylene, 2,5-pyrrolylene, 2,5-pyridinylene, 2,5 - pyrimidinylene), - O -, - S -, - NR 102 -, - COO -, - CONR 103 - , alone or in It is a linking group formed by linking a plurality. R ₁₀₂ and R ₁₀₃ are each independently a hydrogen atom, an alkyl group (preferably having a C number of 1 to 20, such as methyl, ethyl, benzyl) or an alkenyl group (preferably having a C number of 2 to 20, such as vinyl or allyl), cyclo An alkyl group (preferably having 3 to 20 carbon atoms such as cyclohexyl or cyclopentyl), an aryl group (preferably having 6 to 20 carbon atoms such as phenyl or 2-naphthyl), a heterocyclic group (preferably having 1 to 20 carbon atoms such as 2 -Thienyl, 2-pyridinyl, 2-pyrimidinyl).

In the general formula (32), n101 represents an integer of 1 to 8, L ₁₀₁ is a nematic liquid crystal core part, a smectic liquid crystal core part, the n101 is preferably 1 or 2 when the cholesteric liquid crystal core part, L ₁₀₁ When n is a discotic nematic liquid crystalline core part or a discotic liquid crystalline core part, n101 is preferably an integer of 3 to 8.
n102 represents 0 or 1.

  The compound represented by the general formula (32) has at least one polymerizable group.

  Specific examples of the liquid crystalline compound having a polymerizable group of the present invention represented by the general formula (32) are shown below, but the present invention is not limited thereto.

  The liquid crystalline compounds of the present invention are described in the methods described in Kouji Okano and Keisuke Kobayashi, “Liquid Crystal Fundamentals”, Bakukan, 1985, “Chemical Review No. 22, Liquid Crystal Chemistry”, 1994, etc. Can be synthesized.

  Next, the photoreactive compound of the present invention will be described in detail.

  Although the photoreactive compound of the present invention may perform two-photon absorption by itself, since the two-photon absorption efficiency of the photoreactive compound itself is low, a two-photon absorption compound different from the photoreactive compound absorbs two photons. The photoreactive compound reacts and changes its structure by electron transfer or energy transfer from the excited state of the two-photon absorption compound generated by absorption to the photoreactive compound, resulting in a liquid crystalline compound, preferably having a polymerizable group The method of modulating the refractive index by changing the alignment state of the low-molecular liquid crystalline compound is more preferable in terms of higher efficiency.

The photoreactive compound for isomerization reaction of the present invention is preferably an azobenzene compound or stilbene compound, and the compound for bimolecular cyclization reaction is preferably cinnamic acid compound, coumarin compound or chalcone compound. Preferred examples of the compound that undergoes a ring-opening reaction include spiropyran compounds and spirooxazine compounds, and preferred examples of the compound that undergoes a ring-closing reaction include diarylethene compounds, fulgide compounds, and fulgimide compounds.
As the photoreactive compound of the present invention, a photoisomerizable compound is more preferable, and an azobenzene compound is more preferable.
The photoisomerization compound may be a low molecular compound or a high molecular compound, but in the case of a high molecular compound, a high molecular compound in which a photoreactive site is pendant is more preferable.

  Specific examples of the photoreactive compound of the present invention are shown below, but the present invention is not limited thereto.

  All of the photoreactive compounds of the present invention are commercially available products or can be synthesized by known methods.

  Next, the two-photon absorption compound of the present invention will be described in detail.

  When a two-photon absorption compound is used separately from the photoreactive compound in the present invention, at the time of two-photon absorption exposure, the two-photon absorption compound undergoes electron transfer or energy transfer from an excited state generated by two-photon absorption, It is preferable to react a photoreactive compound.

In the case of the energy transfer mechanism from the excited state of the two-photon absorption compound, either the Forster mechanism in which energy transfer occurs from the singlet excited state of the two-photon absorption compound or the Dexter mechanism in which energy transfer occurs from the triplet excited state. both are fine.
In that case, in order for energy transfer to occur efficiently, the excitation energy of the two-photon absorption compound is preferably larger than the excitation energy of the photoreactive compound.

On the other hand, in the case of an electron transfer mechanism from an excited state of a two-photon absorption compound, either a mechanism in which electron transfer occurs from a singlet excited state of a two-photon absorption compound or a mechanism in which electron transfer occurs from a triplet excited state may be used. .
In addition, the excited state of the two-photon absorption compound may give an electron to the photoreactive compound or may receive an electron. When electrons are supplied from the excited state of the two-photon absorption compound, in order for the electron transfer to occur efficiently, the orbital (LUMO) energy of the excited electron in the excited state of the two-photon absorption compound is the LUMO orbital of the photoreactive compound. It is preferably higher than energy.
When the two-photon absorption compound excited state receives electrons, in order for electron transfer to occur efficiently, the orbital (HOMO) energy of holes in the excited state of the two-photon absorption compound is the energy of the HOMO orbital of the photoreactive compound. Is preferably lower.

The two-photon absorption compound of the present invention is a compound that performs non-resonant two-photon absorption (a phenomenon in which two photons are simultaneously absorbed and excited in an energy region where there is no (linear) absorption band of the compound).
When applied to a two-photon absorption optical recording material, particularly a two-photon absorption three-dimensional optical recording material, an excited state is efficiently generated by performing two-photon absorption with high sensitivity in order to achieve a high transfer (recording) speed. A two-photon absorbing compound that can be used is needed.
The efficiency with which a two-photon absorption compound performs two-photon absorption is represented by a two-photon absorption cross section δ and is defined by 1GM = 1 × 10 ⁻⁵⁰ cm ⁴ s / photon. The two-photon absorption cross-sectional area δ of the two-photon absorption compound in the two-photon absorption optical recording material of the present invention is preferably 100 GM or more from the viewpoint of improving the writing speed, reducing the size of the laser and reducing the cost, and is 1000 GM or more. Is more preferably 5000 GM or more, and most preferably 10,000 GM or more.

In addition, a pigment | dye here is a general term with respect to the compound which has a part of absorption in an ultraviolet region (preferably 200-400 nm) visible region (400-700 nm) or a near-infrared region (preferably 700-2000 nm), More preferably Is a general term for compounds having a part of absorption in the visible region.
Any two-photon absorption compound may be used in the present invention. For example, cyanine dye, hemicyanine dye, streptocyanine dye, styryl dye, pyrylium dye, merocyanine dye, trinuclear merocyanine dye, tetranuclear merocyanine dye, rhodacyanine dye, complex Cyanine dye, complex merocyanine dye, allopolar dye, arylidene dye, oxonol dye, hemioxonol dye, squalium dye, croconium dye, azurenium dye, coumarin dye, ketocoumarin dye, styrylcoumarin dye, pyran dye, anthraquinone dye, quinone dye, tri Phenylmethane dye, diphenylmethane dye, xanthene dye, thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, azo Element, azomethine dye, fluorenone dye, diarylethene dye, spiropyran dye, fulgide dye, perylene dye, phthaloperylene dye, indigo dye, polyene dye, acridine dye, acridinone dye, diphenylamine dye, quinacridone dye, quinophthalone dye, porphyrin dye, azaporphyrin dye Chlorophyll dyes, phthalocyanine dyes, fused aromatic dyes, styrenic dyes, metallocene dyes, metal complex dyes, phenylene vinylene dyes, stilbazolium dyes, more preferably cyanine dyes, hemicyanine dyes, streptocyanine dyes, styryl dyes , Pyrylium dye, merocyanine dye, trinuclear merocyanine dye, tetranuclear merocyanine dye, rhodacyanine dye, complex cyanine dye, complex Russianine dye, allopolar dye, arylidene dye, oxonol dye, hemioxonol dye, squalium dye, croconium dye, azurenium dye, coumarin dye, ketocoumarin dye, styrylcoumarin dye, pyran dye, anthraquinone dye, quinone dye, triphenylmethane dye, Diphenylmethane dye, thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, azo dye, azomethine dye, perylene dye, phthaloperylene dye, indigo dye, polyene dye, acridine dye, acridinone dye, diphenylamine dye, quinacridone dye, quinophthalone dye, Porphyrin dyes, azaporphyrin dyes, chlorophyll dyes, phthalocyanine dyes, fused aromatic dyes, styrenic dyes, metalloses Dyes, metal complex dyes, stilbazolium dyes, more preferably cyanine dyes, hemicyanine dyes, streptocyanine dyes, styryl dyes, pyrylium dyes, merocyanine dyes, trinuclear merocyanine dyes, tetranuclear merocyanine dyes, rhodacyanine dyes, complex cyanine dyes , Complex merocyanine dye, allopolar dye, arylidene dye, oxonol dye, hemioxonol dye, squalium dye, croconium dye, azurenium dye, ketocoumarin dye, styrylcoumarin dye, pyran dye, anthraquinone dye, quinone dye, triphenylmethane dye, diphenylmethane Dye, thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, azo dye, azomethine dye, indigo dye Polyene dyes, acridine dyes, acridinone dyes, diphenylamine dyes, quinacridone dyes, quinophthalone dyes, azaporphyrin dyes, chlorophyll dyes, phthalocyanine dyes, fused aromatic dyes, metallocene dyes, metal complex dyes, more preferably cyanine dyes, Hemicyanine dye, streptocyanine dye, styryl dye, pyrylium dye, merocyanine dye, arylidene dye, oxonol dye, squalium dye, ketocoumarin dye, styrylcoumarin dye, pyran dye, thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, azo Dyes, polyene dyes, azaporphyrin dyes, chlorophyll dyes, phthalocyanine dyes, metal complex dyes, more preferably cyanine dyes, merocyanes Emissions dyes, arylidene dyes, oxonol dyes, squarylium dyes, azo dyes and phthalocyanine dyes, more preferably a cyanine dye, merocyanine dye ,, oxonol dyes, and most preferably a cyanine dye.

  For more information on these dyes, see F.M. Harmer, “Heterocyclic Compounds-Cyanine Dies and Related Compounds”, John. John Wiley & Sons-New York, London, 1964, by DM Sturmer, “Heterocyclic Compounds in Special Topics in Heterocyclics” Chemistry (Heterocyclic Compounds-Special topics in heterochemical chemistry) , Chapter 14, Section 14, 482-515, John Wiley & Sons-New York, London, 1977, "Rods Chemistry of Carbon Compounds (Rodd ' s Chemistry of Carbon Compounds) "2nd. Ed. vol. IV, part B, 1977, Chapter 15, pages 369-422, published by Elsevier Science Publishing Company Inc., New York, and the like.

  Specific examples of the cyanine dye, merocyanine dye, or oxonol dye include F.I. M.M. HarmeR, Heterocyclic Compounds-Cyanine Dies and Related Compounds, John & Wiley & Sons, New York, London, published in 1964.

  The general formulas of cyanine dye and merocyanine dye are those shown in (XI) and (XII) on pages 21 and 22 of US Pat. No. 5,340,694 (however, the numbers of n12 and n15 are not limited, An integer of 0 or more (preferably an integer of 0 to 4) is preferable.

  When the two-photon absorption compound of the present invention is a cyanine dye, it is preferably represented by the general formula (3).

In the general formula (3), Za ₁ and Za ₂ each represents an atomic group forming a 5-membered or 6-membered nitrogen-containing heterocycle. The 5-membered or 6-membered nitrogen-containing heterocycle formed is preferably an oxazole nucleus having 3 to 25 carbon atoms (hereinafter referred to as C number) (for example, 2-3-methyloxazolyl, 2-3-ethyloxazolyl). , 2-3,4-diethyloxazolyl, 2-3-methylbenzoxazolyl, 2-3-ethylbenzoxazolyl, 2-3-sulfoethylbenzoxazolyl, 2-3-sulfopropyl Benzoxazolyl, 2-3-methylthioethylbenzoxazolyl, 2-3-methoxyethylbenzoxazolyl, 2-3-sulfobutylbenzoxazolyl, 2-3-methyl-β-naphthoxazolyl 2-3-methyl-α-naphthoxazolyl, 2-3-sulfopropyl-β-naphthoxazolyl, 2-3-sulfopropyl-β-naphthoxazolyl, 2-3- ( -Naphthoxyethyl) benzoxazolyl, 2-3,5-dimethylbenzoxazolyl, 2-6-chloro-3-methylbenzoxazolyl, 2-5-bromo-3-methylbenzoxazolyl, 2- 3-ethyl-5-methoxybenzoxazolyl, 2-5-phenyl-3-sulfopropylbenzoxazolyl, 2-5- (4-bromophenyl) -3-sulfobutylbenzoxazolyl, 2-3 -Dimethyl-5,6-dimethylthiobenzoxazolyl), thiazole nuclei having 3 to 25 carbon atoms (for example, 2-methylthiazolyl, 2-3-ethylthiazolyl, 2-3-sulfopropylthiazolyl, 2- 3-sulfobutylthiazolyl, 2-3,4-dimethylthiazolyl, 2-3,4,4-trimethylthiazolyl, 2-3-carboxyethylthiazolyl, 2 -3-methylbenzothiazolyl, 2-3-ethylbenzothiazolyl, 2-3-butylbenzothiazolyl, 2-3-sulfopropylbenzothiazolyl, 2-3-sulfobutylbenzothiazolyl , 2-3-methyl-β-naphthothiazolyl, 2-3-sulfopropyl-γ-naphthothiazolyl, 2-3- (1-naphthoxyethyl) benzothiazolyl, 2-3,5-dimethylbenzothiazolyl, 2-6-chloro -3-methylbenzothiazolyl, 2-6-iodo-3-ethylbenzothiazolyl, 2-5-bromo-3-methylbenzothiazolyl, 2-3-ethyl-5-methoxybenzothiazolyl 2-5-phenyl-3-sulfopropylbenzothiazolyl, 2-5- (4-bromophenyl) -3-sulfobutylbenzothiazolyl, 2-3-dimethyl-5,6- Dimethylthiobenzothiazolyl), imidazole nucleus having 3 to 25 carbon atoms (for example, 2-1,3-diethylimidazolyl, 2-1,3-dimethylimidazolyl, 2-1-methylbenzimidazolyl, 2- 1,3,4-triethylimidazolyl, 2-1,3-diethylbenzimidazolyl, 2-1,3,5-trimethylbenzimidazolyl, 2-6-chloro-1,3-dimethylbenzimidazolyl, 2-5,6-dichloro- 1,3-diethylbenzimidazolyl, 2-1,3-disulfopropyl-5-cyano-6-chlorobenzimidazolyl, etc.), C10-30 indolenine nucleus (for example, 1,3,3-trimethyl) Indolenine), a quinoline nucleus having 9 to 25 carbon atoms (for example, 2-1-methylquinolyl, 2-1-ethylquinone) Ryl, 2-1-methyl 6-chloroquinolyl, 2-1,3-diethylquinolyl, 2-1-methyl-6-methylthioquinolyl, 2-1-sulfopropylquinolyl, 4-1-methylquinolyl, 4- 1-sulfoethylquinolyl, 4-1-methyl-7-chloroquinolyl, 4-1,8-diethylquinolyl, 4-1-methyl-6-methylthioquinolyl, 4-1-sulfopropylquinolyl and the like 0), for example, amino, dimethylamino, diethylamino, dibutylamino, anilino), cyano group, nitro group, hydroxyl group, mercapto group, carboxyl group, sulfo group, phosphonic acid group, acyl group (preferably C number 1-20, for example, acetyl, benzoyl, salicyloyl, pivaloyl), alkoxy group (preferably C number 1-20, for example , Methoxy, butoxy, cyclohexyloxy) a C 3-25 selenazole nucleus (for example, 2-3methylbenzoselenazolyl etc.), a C 5-25 pyridine nucleus (for example, 2-pyridyl etc.) In addition, thiazoline nucleus, oxazoline nucleus, selenazoline nucleus, tellurazoline nucleus, tellurazole nucleus, benzotelrazole nucleus, imidazoline nucleus, imidazo [4,5-quinoxaline] nucleus, oxadiazole nucleus, thiadiazole Examples include a nucleus, a tetrazole nucleus, and a pyrimidine nucleus.

  These may be substituted, and the substituent is preferably, for example, an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, benzyl, 3- Sulfopropyl, 4-sulfobutyl, carboxymethyl, 5-carboxypentyl), alkenyl group (preferably having 2 to 20 carbon atoms, such as vinyl, allyl, 2-butenyl, 1,3-butadienyl), cycloalkyl group (preferably C 3-20, for example cyclopentyl, cyclohexyl), aryl groups (preferably C 6-20, for example phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), heterocyclic groups ( Preferably C number 1-20, for example pyridyl, thienyl, furyl, thiazolyl, imida Lyl, pyrazolyl, pyrrolidino, piperidino, morpholino), alkynyl group (preferably having 2 to 20 carbon atoms, such as ethynyl, 2-propynyl, 1,3-butadiynyl, 2-phenylethynyl), halogen atom (for example, F, CL , BR, I), amino group (preferably C, aryloxy group (preferably C number 6 to 26, for example, phenoxy, 1-naphthoxy), alkylthio group (preferably C number 1 to 20, for example, methylthio, ethylthio) ), An arylthio group (preferably having 6 to 20 carbon atoms, such as phenylthio, 4-chlorophenylthio), an alkylsulfonyl group (preferably having 1 to 20 carbon atoms, such as methanesulfonyl, butanesulfonyl), an arylsulfonyl group (preferably C number 6-20, for example, benzenesulfonyl, paratoluene Sulfonyl), sulfamoyl group (preferably C 0-20, such as sulfamoyl, N-methylsulfamoyl, N-phenylsulfamoyl), carbamoyl group (preferably C 1-20, such as carbamoyl, N-methyl) Carbamoyl, N, N-dimethylcarbamoyl, N-phenylcarbamoyl), acylamino group (preferably having 1 to 20 carbon atoms, such as acetylamino, benzoylamino), imino group (preferably having 2 to 20 carbon atoms, such as phthalimino), acyloxy A group (preferably having 1 to 20 carbon atoms, such as acetyloxy, benzoyloxy), an alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, such as methoxycarbonyl, phenoxycarbonyl), a carbamoylamino group (preferably having 1 to 20 carbon atoms) For example, carbamoylamino N-methylcarbamoylamino, N-phenylcarbamoylamino), more preferably alkyl group, aryl group, heterocyclic group, halogen atom, cyano group, carboxyl group, sulfo group, alkoxy group, sulfamoyl group, carbamoyl. Group, an alkoxycarbonyl group.

  These heterocycles may be further condensed. Preferred examples of the condensed ring include a benzene ring, a benzofuran ring, a pyridine ring, a pyrrole ring, an indole ring, and a thiophene ring.

More preferably, the 5- or 6-membered nitrogen-containing heterocyclic ring formed by Za ₁ and Za ₂ is an oxazole nucleus, an imidazole nucleus, a thiazole nucleus, or an indolenine ring, and more preferably an oxazole nucleus, an imidazole nucleus, or an indolenine ring. A ring, most preferably an oxazole nucleus.

Ra ₁ and Ra ₂ are each independently a hydrogen atom or an alkyl group (preferably having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, benzyl, 3-sulfopropyl. , 4-sulfobutyl, 3-methyl-3-sulfopropyl, 2′-sulfobenzyl, carboxymethyl, 5-carboxypentyl), alkenyl group (preferably having 2 to 20 carbon atoms, for example, vinyl, allyl), aryl group ( Preferably C number 6-20, for example, phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), heterocyclic group (preferably C number 1-20, for example, pyridyl, thienyl, furyl , Thiazolyl, imidazolyl, pyrazolyl, pyrrolidino, piperidino, morpholino), more preferably Alkyl group (preferably an alkyl group having a C number of 1 to 6) or a sulfoalkyl group (preferably 3-sulfopropyl, 4-sulfobutyl, 3-methyl-3-sulfopropyl, 2'-sulfobenzyl) is.

Ma _{1 to} Ma ₇ each represent a methine group and may have a substituent (examples of preferred substituents are the same as examples of substituents on Za ₁ and Za ₂ ), and an alkyl group is preferred as the substituent. , Halogen atom, nitro group, alkoxy group, aryl group, nitro group, heterocyclic group, aryloxy group, acylamino group, carbamoyl group, sulfo group, hydroxy group, carboxy group, alkylthio group, cyano group, etc. More preferably, it is an alkyl group.
Ma _{1 to} Ma ₇ are preferably an unsubstituted methine group or an alkyl group (preferably having a C number of 1 to 6) substituted methine group, and more preferably an unsubstituted, ethyl group-substituted, or methyl group-substituted methine group.
Ma _{1 to} Ma ₇ may be linked to each other to form a ring, and preferred examples of the ring formed include a cyclohexene ring, a cyclopentene ring, a benzene ring, and a thiophene ring.

na ¹ and na ² are 0 or 1, preferably both 0.

ka ¹ represents an integer of 0 to 3, more preferably ka ¹ represents 0 to 2, and further preferably ka ¹ represents 1 or 2.
When ka ¹ is 2 or more, the plurality of Ma ₃ and Ma ₄ may be the same or different.

  CI represents an ion for neutralizing the electric charge, and y represents a number necessary for neutralizing the electric charge.

  When the two-photon absorption compound of the present invention is a merocyanine dye, it is preferably represented by the general formula (4).

In the general formula (4), Za ₃ represents a group of atoms forming a 5-membered or 6-membered nitrogen-containing heterocycle (preferred examples are the same as Za ₁ and Za ₂ ), and these may be substituted (preferred substitution). examples of groups are the same as examples of the substituent on Za1, Za _2)), these heterocyclic rings may be further condensed with another ring.

The 5- or 6-membered nitrogen-containing heterocycle formed by Za ₃ is more preferably an oxazole nucleus, an imidazole nucleus, a thiazole nucleus or an indolenine ring, and more preferably an oxazole nucleus, a thiazole nucleus or an indolenine ring. .

Za ₄ represents an atomic group forming a 5-membered or 6-membered ring. The ring formed from Za ₄ is a part generally called an acidic nucleus, and is defined by James ed., The Theory of the Photographic Process, 4th edition, McMillan, 1977, p. 198. Za ₄ is preferably 2-pyrazolone-5-one, pyrazolidine-3,5-dione, imidazolin-5-one, hydantoin, 2 or 4-thiohydantoin, 2-iminooxazolidine-4-one, 2-oxazoline- 5-one, 2-thiooxazoline-2,4-dione, isorhodanine, rhodanine, indan-1,3-dione, thiophen-3-one, thiophen-3-one-1,1-dioxide, indoline-2-one Indoline-3-one, 2-oxoindazolium, 5,7-dioxo-6,7-dihydrothiazolo [3,2-a] pyrimidine, 3,4-dihydroisoquinolin-4-one, 1,3 -Dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, coumarin-2,4-dione, indazoline-2- Emissions, pyrido [1,2-a] pyrimidine-1,3-dione, pyrazolo [1,5-b] quinazolone include nuclei such pyrazolopyridone.
More preferably, the ring formed from Za ₄ is 2-pyrazolone-5-one, pyrazolidine-3,5-dione, rhodanine, indan-1,3-dione, thiophen-3-one, thiophen-3-one- 1,1-dioxide, 1,3-dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, coumarin-2,4-dione, more preferably pyrazolidine-3,5-dione, Indan-1,3-dione, 1,3-dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, particularly preferably pyrazolidine-3,5-dione, barbituric acid, 2- Thiobarbituric acid, most preferably 2-thiobarbituric acid.

The ring formed from Za ₄ may be substituted (preferred examples of the substituent are the same as the examples of the substituent on Za ₃ ), and more preferably an alkyl group, aryl group, heterocyclic group, halogen An atom, a cyano group, a carboxyl group, a sulfo group, an alkoxy group, a sulfamoyl group, a carbamoyl group, and an alkoxycarbonyl group.

  These heterocycles may be further condensed. Preferred examples of the condensed ring include a benzene ring, a benzofuran ring, a pyridine ring, a pyrrole ring, an indole ring, and a thiophene ring.

Each of Ra ₃ is independently a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group (preferred examples are the same as Ra ₁ and Ra ₂ ), more preferably an alkyl group (preferably having a C number of 1 to 6). Alkyl group) or a sulfoalkyl group (preferably 3-sulfopropyl, 4-sulfobutyl, 3-methyl-3-sulfopropyl, 2′-sulfobenzyl).

Ma _{8 to} Ma ₁₁ each represent a methine group and may have a substituent (examples of preferred substituents are the same as the examples of substituents on Za ₁ and Za ₂ ), and an alkyl group is preferred as the substituent. , Halogen atom, nitro group, alkoxy group, aryl group, nitro group, heterocyclic group, aryloxy group, acylamino group, carbamoyl group, sulfo group, hydroxy group, carboxy group, alkylthio group, cyano group, etc. More preferably, it is an alkyl group.
Ma _{8 to} Ma ₁₁ are preferably an unsubstituted methine group or an alkyl group (preferably C 1-6) substituted methine group, more preferably an unsubstituted, ethyl group-substituted, or methyl group-substituted methine group.
Ma _{8 to} Ma ₁₁ may be linked to each other to form a ring, and preferred examples of the ring formed include a cyclohexene ring, a cyclopentene ring, a benzene ring, and a thiophene ring.

na ³ is 0 or 1, preferably 0.

ka ² represents an integer of 0 to 8, preferably an integer of 0 to 4, more preferably an integer of 1 to 3.
When ka ² is 2 or more, the plurality of Ma ₁₀ and Ma ₁₁ may be the same or different.

  CI represents an ion for neutralizing the electric charge, and y represents a number necessary for neutralizing the electric charge.

  When the two-photon absorption compound of the present invention is an oxonol dye, it is preferably represented by the general formula (5).

In the general formula (5), Za ₅ and Za ₆ each represent a group of atoms forming a 5-membered or 6-membered ring (preferred examples are the same as Za ₄ ), and these may be substituted (examples of preferred substituents). Is the same as the example of the substituent on Za ₄ ), and these heterocyclic rings may be further condensed.
More preferably, the ring formed from Za ₅ and Za ₆ is more preferably 2-pyrazolone-5-one, pyrazolidine-3,5-dione, rhodanine, indan-1,3-dione, thiophen-3-one, thiophene-3 -One-1,1-dioxide, 1,3-dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, coumarin-2,4-dione, more preferably barbituric acid, 2- Thiobarbituric acid, most preferably barbituric acid.

Ma _{12 to} Ma ₁₄ each represent a methine group and may have a substituent (preferred examples of the substituent are the same as the examples of the substituents on Za ₅ and Za ₆ ). Group, halogen atom, nitro group, alkoxy group, aryl group, nitro group, heterocyclic group, aryloxy group, acylamino group, carbamoyl group, sulfo group, hydroxy group, carboxy group, alkylthio group, cyano group, etc. An alkyl group, a halogen atom, an alkoxy group, an aryl group, a heterocyclic group, a carbamoyl group, and a carboxy group are more preferable, and an alkyl group, an aryl group, and a heterocyclic group are more preferable.
Ma _{12 to} Ma ₁₄ are preferably unsubstituted methine groups.
Ma _{12 to} Ma ₁₄ may be linked to each other to form a ring, and preferred examples of the ring formed include a cyclohexene ring, a cyclopentene ring, a benzene ring, and a thiophene ring.

ka ³ represents an integer of 0 to 3, preferably represents an integer of 0 to 2, and more preferably represents 1 or 2.
When ka ³ is 2 or more, Ma ₁₂ and Ma ₁₃ may be the same or different.

  CI represents an ion that neutralizes charge, and y represents a number necessary for charge neutralization.

  Moreover, it is also preferable that the compound of this invention is represented by General formula (1).

In the general formula (1), R ¹ , R ² , R ³ and R ⁴ each independently represents a hydrogen atom or a substituent, and the substituent is preferably an alkyl group (preferably having a C number of 1 to 20, for example, Methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, benzyl, 3-sulfopropyl, 4-sulfobutyl, 3-methyl-3-sulfopropyl, 2'-sulfobenzyl, carboxymethyl, 5-carboxy Pentyl), an alkenyl group (preferably C 2-20, such as vinyl, allyl), a cycloalkyl group (preferably C 3-20, such as cyclopentyl, cyclohexyl), an aryl group (preferably C 6-20, For example, phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), a heterocyclic group (preferably C number of 1 to 20, for example, pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, pyrrolidino, piperidino, morpholino).
R ¹ , R ² , R ³ and R ⁴ are preferably a hydrogen atom or an alkyl group. Some (preferably two) of R ¹ , R ² , R ³ and R ⁴ may be bonded to each other to form a ring. In particular, R ¹ and R ³ are preferably bonded to form a ring, and the ring formed with the carbonyl carbon atom is preferably a 6-membered ring, a 5-membered ring or a 4-membered ring, and a 5-membered ring or A 4-membered ring is more preferable, and a 5-membered ring is most preferable.

In General formula (1), n and M represent the integer of 0-4 each independently, Preferably the integer of 1-4 is represented. However, n and M are not 0 simultaneously.
When n and M are 2 or more, a plurality of R ¹ , R ² , R ³ and R ⁴ may be the same or different.

X ¹ and X ² are independently an aryl group [preferably a C 6-20, preferably a substituted aryl group (for example, a substituted phenyl group, a substituted naphthyl group, a substituent of Ma ₁ to Ma ₇ as an example of a substituent, preferably And more preferably an alkyl group, an aryl group, a heterocyclic group, a halogen atom, an amino group, a hydroxyl group, an alkoxy group, an aryloxy group, an aryl group substituted with an acylamino group, and more preferably an alkyl group Represents an aryl group substituted with an amino group, a hydroxyl group, an alkoxy group or an acylamino group, and most preferably a phenyl group substituted with a dialkylamino group or a diarylamino group at the 4-position. At that time, a plurality of substituents may be linked to form a ring, and a preferred ring formed includes a julolidine ring. ], A heterocyclic group (preferably having 1 to 20 carbon atoms, preferably 3 to 8 membered ring, more preferably 5 or 6 membered ring such as pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, pyrrolyl, indolyl, carbazolyl, Phenothiazino, pyrrolidino, piperidino, morpholino, more preferably indolyl, carbazolyl, pyrrolyl, phenothiazino, the heterocycle may be substituted, and preferred substituents are the same as in the case of the aryl group), or the general formula (2) Represents a group represented by

In the general formula (2), R ⁵ represents a hydrogen atom or a substituent (preferred examples are the same as those of R ^{1 to} R ⁴ ), preferably a hydrogen atom or an alkyl group, and more preferably a hydrogen atom.
R ⁶ represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group (preferable examples of these substituents are the same as R ^{1 to} R ⁴ ), preferably an alkyl group (preferably having a C number of 1 to 6 alkyl groups).

Z ¹ represents an atomic group forming a 5- or 6-membered ring.
The heterocycle formed is preferably an indolenine ring, azaindolenine ring, pyrazoline ring, benzothiazole ring, thiazole ring, thiazoline ring, benzoxazole ring, oxazole ring, oxazoline ring, benzimidazole ring, imidazole ring, thiadiazole ring Quinoline ring, pyridine ring, more preferably indolenine ring, azaindolenine ring, pyrazoline ring, benzothiazole ring, thiazole ring, thiazoline ring, benzoxazole ring, oxazole ring, oxazoline ring, benzimidazole ring, thiadiazole ring A quinoline ring, most preferably an indolenine ring, an azaindolenine ring, a benzothiazole ring, a benzoxazole ring, or a benzimidazole ring.
The heterocycle formed by Z ¹ may have a substituent (examples of preferred substituents are the same as those of the substituents on Za ₁ and Za ₂ ), and more preferably an alkyl group, aryl A group, a heterocyclic group, a halogen atom, a carboxyl group, a sulfo group, an alkoxy group, a carbamoyl group, and an alkoxycarbonyl group.

X ¹ and X ² are each preferably an aryl group or a group represented by the general formula (2), more preferably an aryl group substituted with a dialkylamino group or a diarylamino group at the 4-position, or a general formula (2) Represented by the group represented.

The two-photon absorption compound of the present invention preferably has a hydrogen bonding group in the molecule. Here, the hydrogen-bonding group represents a group that donates hydrogen or a group that accepts hydrogen in a hydrogen bond, and a group having both properties is more preferable.
Further, the compound having a hydrogen bonding group of the present invention preferably has an associative interaction by the interaction between hydrogen bonding groups in a solution or in a solid state, and may be an intramolecular interaction or an intermolecular interaction. The interaction is more preferable.

The hydrogen bonding group of the present invention is preferably —COOH, —CONHR ¹¹ , —SO ₃ H, —SO ₂ NHR ¹² , —P (O) (OH) OR ¹³ , —OH, —SH, —NHR. ¹⁴ , —NHCOR ¹⁵ , or —NR ¹⁶ C (O) NHR ¹⁷ . Here, R ¹¹ and R ¹² are each independently a hydrogen atom or an alkyl group (preferably having a carbon atom number (hereinafter referred to as C number) of 1 to 20, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, n -Pentyl, benzyl, 3-sulfopropyl, 4-sulfobutyl, carboxymethyl, 5-carboxypentyl), alkenyl group (preferably C 2-20, for example, vinyl, allyl), aryl group (preferably C 6- 20, for example, phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), a heterocyclic group (preferably having 1 to 20 carbon atoms, such as pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl) , pyrrolidino, piperidino, morpholino), - represents COR ¹⁸ or _{^{-SO 2 R 19, R 13 ~R}} 19 is Respectively independently a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or a heterocyclic group (preferred examples above are the same as R ^11, R ^12).

R ¹¹ preferably represents a hydrogen atom, an alkyl group, an aryl group, a —COR ¹⁸ group, or a SO ₂ R ¹⁹ group. In this case, R ¹⁸ and R ¹⁹ are preferably an alkyl group or an aryl group.
R ¹¹ is more preferably a hydrogen atom, an alkyl group, or a —SO ₂ R ¹⁹ group, and most preferably a hydrogen atom.
R ¹² preferably represents a hydrogen atom, an alkyl group, an aryl group, a —COR ¹⁸ group, or a SO ₂ R ¹⁹ group. In this case, R ¹⁸ and R ¹⁹ are preferably an alkyl group or an aryl group.
R ¹² is more preferably a hydrogen atom, an alkyl group or a —COR ¹⁸ group, and most preferably a hydrogen atom.
R ¹³ preferably represents a hydrogen atom, an alkyl group, or an aryl group, more preferably a hydrogen atom.
R ¹⁴ preferably represents a hydrogen atom, an alkyl group or an aryl group.
R ¹⁵ preferably represents an alkyl group or an aryl group.
R ¹⁶ preferably represents a hydrogen atom, and R ¹⁷ preferably represents a hydrogen atom, an alkyl group, or an aryl group.

The hydrogen bonding group is more preferably any one of —COOH, —CONHR ¹¹ , —SO ₂ NHR ¹² , —NHCOR ¹⁵ , —NR ¹⁶ C (O) NHR ¹⁷ , and more preferably —COOH, —CONHR ^11. , —SO ₂ NHR ¹² , and most preferably —COOH or —CONH ₂ .

The two-photon absorption compound of the present invention may be used in a monomer state or in an associated state.
Here, the dye chromophores are fixed in a specific spatial arrangement by a bond such as a covalent bond or a coordinate bond, or various intermolecular forces (hydrogen bond, van der Waals force, Coulomb force, etc.) This state is generally referred to as an association (or aggregation) state.
The two-photon absorption compound of the present invention has two or more chromophores that perform two-photon absorption in a molecule even when used in an intermolecular association state, and is used in a state in which they absorb two-photons in an intramolecular association state. May be.

For reference, the meeting is explained below. As for the association, for example, James, “The Theory of the Photographic Process”, 4th edition, Macmillan Publishing Company, 1977, Chapter 8, 218. Pp. 222 and “J-Aggregates” written by Takabayashi Kobayashi (World Scientific Publishing Co. Pte. Ltd., 1996)). .
A monomer means a monomer. From the viewpoint of the absorption wavelength of the aggregate, the aggregate whose absorption shifts to a short wavelength with respect to monomer absorption is defined as an H aggregate (the dimer is specially called a dimer), and the aggregate whose shift is shifted to a long wavelength. Called coalescence.

  From the viewpoint of the structure of the aggregate, in a brick-stacked aggregate, when the deviation angle of the aggregate is small, it is called a J aggregate, but when the deviation angle is large, it is called an H aggregate. Brickwork aggregates are described in detail in Chemical Physics Letters, Vol. 6, page 183 (1970). In addition, there is a ladder or staircase aggregate as an aggregate having a structure similar to that of a brickwork aggregate. Ladder or staircase structures are described in detail in Zeitschiff for Physikaliche Chemie, Vol. 49, p. 324 (1941).

Moreover, as what forms other than a brickwork aggregate | assembly, the aggregate | assembly (it can call an arrowhead aggregate | assembly) etc. which take an arrow (Herringbone) structure etc. are known.
The Herringbone association is described in Charles Reich, Photographic Science and Engineering Vol. 18, No. 3, p. 335 (1974). Has been. The arrowhead aggregate has two absorption maxima derived from the aggregate.

Whether or not an association state is taken can be confirmed by a change in absorption from the monomer state (absorption λMax, ε, absorption type) as described above.
The compound of the present invention may be either short-wavelength (H-association) or long-wavelength (J-association) or both by association, but it is more preferable to form a J-aggregate.

The intermolecular association state of a compound can be formed in various ways.
For example, in a solution system, an aqueous solution to which a matrix such as gelatin is added (for example, gelatin 0.5 wt% · compound 10 ⁻⁴ M aqueous solution), an aqueous solution to which a salt such as KCl is added (eg, KCl 5% · compound 2 × 10 ^−3). M aqueous solution), a method of dissolving a compound in a good solvent, a method of adding a poor solvent afterwards (for example, DMF-water system, chloroform-toluene system, etc.) and the like.
Examples of the film system include a polymer dispersion system, an amorphous system, a crystal system, and an LB film system.
Furthermore, molecules can be adsorbed, chemically bonded, or self-assembled into bulk or fine particle (μm to nm size) semiconductors (eg, silver halide, titanium oxide, etc.), bulk or fine particle metals (eg, gold, silver, platinum, etc.). Inter-association states can also be formed. Spectral sensitization by cyanine dye J-associative adsorption on silver halide crystals in a color silver salt photograph utilizes this technique.
The number of compounds involved in the intermolecular association may be two or a very large number of compounds.

  Although the preferable specific example of the two-photon absorption compound used by this invention is given to the following, this invention is not limited to these.

Next, the polymerization initiator in the two-photon absorption optical recording material of the present invention will be described in detail.
The polymerization initiator of the present invention refers to radicals or radicals generated by energy transfer or electron transfer (giving or receiving electrons) from the excited state of a two-photon absorption compound or photoreactive compound, or by direct excitation. It is a compound capable of generating an acid (Bronsted acid or Lewis acid) and a base (Bronsted base or Lewis base) and initiating polymerization of the polymerizable compound.

  The polymerization initiator of the present invention is preferably a radical polymerization initiator capable of generating radicals to initiate radical polymerization of polymerizable compounds, and cationic polymerization of polymerizable compounds by generating only acids without generating radicals. A cationic polymerization initiator capable of initiating only a radical, a polymerization initiator capable of initiating both radicals and acids to initiate both radical and cationic polymerization, an anionic polymerization initiating capable of initiating anion polymerization by generating a base One of the agents.

First, a radical polymerization initiator, a cationic polymerization initiator, and an initiator capable of initiating both will be described.
The polymerization initiator of the present invention preferably includes the following 12 systems. In addition, you may use these polymerization initiators as 2 or more types of mixtures by arbitrary ratios as needed.

1) ketone polymerization initiator 2) organic peroxide polymerization initiator 3) bisimidazole polymerization initiator 4) trihalomethyl-substituted triazine polymerization initiator 5) diazonium salt polymerization initiator 6) diaryliodonium salt polymerization Initiator 7) sulfonium salt polymerization initiator 8) borate polymerization initiator 9) diaryliodonium organic boron complex polymerization initiator 10) sulfonium organic boron complex polymerization initiator 11) metal arene complex polymerization initiator 12 ) Sulphonic acid ester polymerization initiator

1) Ketone-based polymerization initiator

Preferred examples of the ketone polymerization initiator include aromatic ketones and aromatic diketones.
Preferred examples include, for example, benzophenone derivatives (for example, benzophenone, Michler's ketone), benzoin derivatives (for example, benzoin methyl ether, benzoin ethyl ether, α-methylbenzoin, α-allylbenzoin, α-phenylbenzoin), acetoin derivatives (acetoin, pivaloin, 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexyl phenyl ketone), acyloin ether derivatives (eg diethoxyacetophenone), α-diketone derivatives (diacetyl, benzyl, 4,4′-dimethoxybenzyl, benzyldimethyl ketal) , 2,3-bornanedione (camphorquinone), 2,2,5,5-tetramethyltetrahydro-3,4-furanic acid (imidazole trione)), xanthone derivative (For example, xanthone), thioxanthone derivatives (for example, thioxanthone, 2-chlorothioxanthone), ketocoumarin derivatives, and the like.

  Examples of commercially available products include Irgacure 184, 651, and 907 represented by the following formula marketed by Ciba Geigy.

  Preferred examples include quinone polymerization initiators (for example, 9,10-anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone. Quinone, octamethylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-methyl-1,4-naphthoquinone, 2, 3-dichloronaphthoquinone, 1,4-dimethylanthraquinone, 2,3-dimethylanthraquinone, 2-phenylanthraquinone, 2,3-dimethylanthraquinone, sodium salt of anthraquinone alpha-sulfonic acid, 3-chloro-2 -Methylanthraquinone, Rethenequinone, 7,8,9,10-tetra Mud naphthacene quinone, and 1,2,3,4-tetrahydrobenz (a) anthracene-7,12-dione) can be mentioned.

2) Organic peroxide polymerization initiator

Preferable examples include benzoyl peroxide, di-t-butyl peroxide, 3,3 ′, 4,4′-tetra (t-) described in JP-A-59-189340 and JP-A-60-76503. Butylperoxycarbonyl) benzophenone and the like.

3) Bisimidazole polymerization initiator

  Preferable bisimidazole-based polymerization initiators are bis (2,4,5-triphenyl) imidazole derivatives, such as bis (2,4,5-triphenyl) imidazole, 2- (o-chlorophenyl)- 4,5-bis (M-methoxyphenyl) -imidazole dimer (CDM-HABI), 1,1'-biimidazole, 2,2'-bis (o-chlorophenyl) -4,4'5,5'-tetra Examples include phenyl (o-CL-HABI), 1H-imidazole, 2,5-bis (o-chlorophenyl) -4- [3,4-dimethoxyphenyl] -dimer (TCTM-HABI), and the like.

  The bisimidazole polymerization initiator is preferably used together with a hydrogen donor. Preferred examples of the hydrogen donor include 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 4-methyl-4H-1,2,4-triazole-3-thiol, and the like.

4) Trihalomethyl-substituted triazine polymerization initiator

  The trihalomethyl-substituted triazine acid generator is preferably represented by the following general formula (11).

In the general formula (11), R ₂₁ , R ₂₂ and R ₂₃ each independently represent a halogen atom, preferably a chlorine atom. R ₂₄ and R ₂₅ each independently represent a hydrogen atom, —CR ₂₁ R ₂₂ R ₂₃ , or a substituent.
Preferred examples of the substituent include, for example, an alkyl group (preferably having a C number of 1 to 20, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, benzyl, 3-sulfopropyl, 4-sulfobutyl, Carboxymethyl, 5-carboxypentyl), alkenyl group (preferably C 2-20, for example, vinyl, allyl, 2-butenyl, 1,3-butadienyl), cycloalkyl group (preferably C 3-20, for example, Cyclopentyl, cyclohexyl), an aryl group (preferably having 6 to 20 carbon atoms, for example, phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), a heterocyclic group (preferably having 1 to 20 carbon atoms). For example, pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, pyro Dino, piperidino, morpholino), alkynyl groups (preferably C 2-20, eg ethynyl, 2-propynyl, 1,3-butadiynyl, 2-phenylethynyl), halogen atoms (eg F, Cl, Br, I ), Amino group (preferably C 0-20, such as amino, dimethylamino, diethylamino, dibutylamino, anilino), cyano group, nitro group, hydroxyl group, mercapto group, carboxyl group, sulfo group, phosphonic acid group, An acyl group (preferably having 1 to 20 carbon atoms, such as acetyl, benzoyl, salicyloyl, pivaloyl), an alkoxy group (preferably having 1 to 20 carbon atoms, such as methoxy, butoxy, cyclohexyloxy), an aryloxy group (preferably having C number) Formula 6-26, for example, phenoxy, 1-naphthoxy), alkyl O group (preferably C number 1-20, for example, methylthio, ethylthio), arylthio group (preferably C number 6-20, for example, phenylthio, 4-chlorophenylthio), alkylsulfonyl group (preferably C number 1-20) , For example, methanesulfonyl, butanesulfonyl), arylsulfonyl group (preferably C number 6-20, such as benzenesulfonyl, paratoluenesulfonyl), sulfamoyl group (preferably C number 0-20, such as sulfamoyl, N-methyl) Sulfamoyl, N-phenylsulfamoyl), carbamoyl group (preferably having 1 to 20 carbon atoms, for example, carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-phenylcarbamoyl), acylamino group (preferably C number 1-20, for example, acetyla Mino, benzoylamino), imino group (preferably C 2-20, eg phthalimino), acyloxy group (preferably C 1-20, eg acetyloxy, benzoyloxy), alkoxycarbonyl group (preferably C 2 20, for example, methoxycarbonyl, phenoxycarbonyl), a carbamoylamino group (preferably having a C number of 1-20, such as carbamoylamino, N-methylcarbamoylamino, N-phenylcarbamoylamino), more preferably an alkyl group, An aryl group, a heterocyclic group, a halogen atom, a cyano group, a carboxyl group, a sulfo group, an alkoxy group, a sulfamoyl group, a carbamoyl group, and an alkoxycarbonyl group.
R ₂₄ is preferably a -CR ₂₁ R ₂₂ R _23, more preferably represents a ₃ group -CCl, R ₂₅ is preferably, -CR ₂₁ R ₂₂ R _23, an alkyl group, an alkenyl group, an aryl group.

  Specific examples of the trihalomethyl-substituted triazine polymerization initiator include 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2,4,6-tris (trichloromethyl) -1, 3,5-triazine, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4′-methoxyphenyl) -4,6-bis (trichloromethyl) -1, 3,5-triazine, 2- (4′-trifluoromethylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (p -Methoxyphenylvinyl) -1,3,5-triazine, 2- (4′-methoxy-1′-naphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine and the like are exemplified. . Preferable examples also include compounds described in British Patent No. 1388492 and JP-A No. 53-133428.

5) Diazonium salt polymerization initiator

  The diazonium salt polymerization initiator is preferably represented by the following general formula (12).

R ₂₆ represents an aryl group or a heterocyclic group, preferably an aryl group, and more preferably a phenyl group.
R ₂₇ is (the same as examples of preferably substituents exemplified for R ₂₄ as above substituents) represent a substituent, a21 represents an integer of 0 to 5, preferably an integer of 0 to 2. a21 is when 2 or more, the plurality of R ₂₇ may be the same or different and may form a ring.
X ₂₁ ⁻ is an anion in which HX ₂₁ becomes an acid having a pka of 4 or less (in water, 25 ° C.), preferably 3 or less, more preferably 2 or less, and preferably, for example, chloride, bromide, iodide, tetrafluoroborate, hexa Fluorophosphate, hexafluoroarsenate, hexafluoroantimonate, perchlorate, trifluoromethanesulfonate, 9,10-dimethoxyanthracene-2-sulfonate, methanesulfonate, benzenesulfonate, 4-trifluoromethylbenzenesulfonate, tosylate, tetra (penta Fluorophenyl) borate and the like.

Specific examples of the diazonium-based polymerization initiator such as benzene diazonium, 4-methoxy diazonium, 4-methyl aforementioned X ₂₁ of diazonium ^- such salts.

6) Diaryliodonium salt polymerization initiator

  The diaryliodonium salt polymerization initiator is preferably represented by the following general formula (13).

In general formula (13), X ₂₁ ^- has the same meaning as in general formula (12). R ₂₈ and R ₂₉ each independently represents a substituent (preferably the same as the examples of substituents mentioned for R ₂₄ as substituents above), preferably an alkyl group, an alkoxy group, a halogen atom, a cyano group, nitro Represents a group.
a22 and a23 each independently represent an integer of 0 to 5, preferably an integer of 0 to 1. When a21 is 2 or more, a plurality of R ₂₈ and R ₂₉ may be the same or different, and may be connected to each other to form a ring.

Specific examples of the diaryliodonium salt polymerization initiator include diphenyliodonium, 4,4′-dichlorodiphenyliodonium, 4,4′-dimethoxydiphenyliodonium, 4,4′-dimethyldiphenyliodonium, 4,4′-di- t-butyldiphenyliodonium, 4,4′-di-t-amyldiphenyliodonium, 3,3′-dinitrodiphenyliodonium, phenyl (p-methoxyphenyl) iodonium, phenyl (p-octyloxyphenyl) iodonium, bis (p Chloride such as cyanophenyl) iodonium, bromide, iodide, tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, perchlorate, trifluoromethanesulfonate, 9,10 Dimethoxy anthracene-2-sulfonate, methanesulfonate, benzenesulfonate, 4-trifluoromethylbenzenesulfonate, tosylate, tetra (pentafluorophenyl) borate, perfluorobutanesulfonate and pentafluorobenzenesulfonate sulfonates.
Further, compounds described in “Macromolecules”, Vol. 10, p1307 (1977), Japanese Patent Application Laid-Open No. 58-29803, Japanese Patent Application Laid-Open No. 1-287105, Japanese Patent Application No. 3-5569. And diaryliodonium salts as described in 1).

7) Sulfonium salt polymerization initiator

  The sulfonium salt polymerization initiator is preferably represented by the following general formula (14).

In general formula (14), X ₂₁ ^- has the same meaning as in general formula (12). R _30, R _31, R ₃₂ each independently represent an alkyl group, an aryl group, a Hajime Tamaki (preferred examples above same as those for R _24), preferably an alkyl group, a phenacyl group, an aryl group.

  Specific examples of the sulfonium salt polymerization initiator include triphenylsulfonium, diphenylphenacylsulfonium, dimethylphenacylsulfonium, benzyl-4-hydroxyphenylmethylsulfonium, 4-tertiarybutyltriphenylsulfonium, tris (4-methylphenyl). ) Chloride, bromide, tetrafluoroborate, hexafluorophosphate of sulfonium salts such as sulfonium, tris (4-methoxyphenyl) sulfonium, 4-phenylthiotriphenylsulfonium, bis-1- (4- (diphenylsulfonium) phenyl) sulfide , Hexafluoroarsenate, hexafluoroantimonate, perchlorate, trifluoromethanesulfonate, 9,10-dimethoxyanthracene-2-s Honeto, methanesulfonate, benzenesulfonate, 4-trifluoromethylbenzenesulfonate, tosylate, tetra (pentafluorophenyl) borate, perfluorobutanesulfonate, and pentafluorophenyl benzenesulfonate and the like.

8) Borate polymerization initiator

  The borate polymerization initiator is preferably represented by the following general formula (15).

In the general formula (15), R ₃₃ , R ₃₄ , R ₃₅ and R ₃₆ each independently represents an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group or an aryl group (preferred examples are the same as those for R ₂₄ ). And preferably an alkyl group or an aryl group. However, not all of R ₃₃ , R ₃₄ , R ₃₅ , and R ₃₆ become an aryl group at the same time. X ₂₂ ⁺ represents a cation. More preferably, R ₃₃ , R ₃₄ and R ₃₅ are aryl groups, R ₃₆ is an alkyl group, most preferably R ₃₃ , R ₃₄ and R ₃₅ are phenyl groups, and R ₃₆ is an n-butyl group. is there.

  Specific examples of the borate polymerization initiator include tetrabutylammonium n-butyltriphenylborate, tetramethylammonium sec-butyltriphenylborate and the like.

9) Diaryliodonium organoboron complex polymerization initiator

  The diaryliodonium organoboron complex salt polymerization initiator is preferably represented by the following general formula (16).

In general formula (16), R ₂₈ , R ₂₉ , a22 and a23 have the same meaning as in general formula (13), and R ₃₃ , R ₃₄ , R ₃₅ and R ₃₆ have the same meaning as in general formula (15).

  Specific examples of the diaryliodonium organic boron complex salt polymerization initiator include I-1 to I-3 shown below.

  Furthermore, iodonium organoboron complexes such as diphenyliodonium (n-butyl) triphenylborate described in JP-A-3-704 are also preferable examples.

10) Sulfonium organoboron complex polymerization initiator

  The sulfonium organic boron complex salt polymerization initiator is preferably represented by the following general formula (17).

In general formula (17), R ₃₃ , R ₃₄ , R ₃₅ , and R ₃₆ have the same _{meaning as} in general formula (15). R ₃₇ , R ₃₈ and R ₃₉ are each independently an alkyl group, an aryl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group or an amino group (and more preferred examples). Is the same as R ₂₄ ), more preferably an alkyl group, a phenacyl group, an aryl group or an alkenyl group. R ₃₇ , R ₃₈ and R ₃₉ may be connected to each other to form a ring. R ₄₀ represents an oxygen atom or a lone electron pair.

  Specific examples of the sulfonium organic boron complex salt polymerization initiator include I-4 to I-10 shown below.

  Furthermore, preferred examples include sulfonium organoboron complexes described in JP-A-5-255347 and JP-A-5-213861.

11) Metal arene complex polymerization initiator

As the metal arene complex polymerization initiator, the metal is preferably iron or titanium.
Specifically, JP-A-1-54440, European Patent No. 109851, European Patent No. 126712 and “Journal of Imaging Science (J. Imag. Sci.)”, Volume 30, page 174 ( 1986), an iron arene complex described in “Organometallics”, Vol. 8, page 2737 (1989), “Prog. Polym. Sci, Vol. 21, 7- Preferable examples include iron arene complex salts described on page 8 (1996) and titacenones described in JP-A No. 61-151197.

12) Sulfonic acid ester polymerization initiator

  Preferred examples of the sulfonic acid ester polymerization initiator include sulfonic acid esters, sulfonic acid nitrobenzyl esters, imide sulfonates, and the like.

  Specific examples of sulfonic acid esters are preferably benzoin tosylate, pyrogallol trimesylate, and specific examples of sulfonic acid nitrobenzyl esters are preferably o-nitrobenzyl tosylate, 2,6-dinitrobenzyl tosylate, Specific examples of 2 ′, 6′-dinitrobenzyl-4-nitrobenzenesulfonate, p-nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate, 2-nitrobenzyltrifluoromethylsulfonate, and imidosulfonate are preferably N. -Tosylphthalimide, 9-fluorenylideneaminotosylate, α-cyanobenzylidenetosylamine, and the like.

13) Other polymerization initiators

Examples of the polymerization initiator other than the above 1) to 14) include organic azide compounds such as 4,4′-diazidochalcone, aromatic carboxylic acids such as N-phenylglycine, polyhalogen compounds (CI ₄ , CHI ₃ , CBRCI ₃ ), pyridinium salts such as 1-benzyl-2-cyanopyridinium salt hexafluoroantimonate, phenylisoxazolone, silanol aluminum complexes, and aluminate complexes described in JP-A-3-209477.

Here, the radical or cationic polymerization initiator of the present invention is
a) Polymerization initiator capable of activating radical polymerization b) Polymerization initiator capable of activating only cationic polymerization c) Polymerization initiator capable of simultaneously activating radical polymerization and cationic polymerization can be classified.

a) A polymerization initiator capable of activating radical polymerization is energy transfer or electron transfer from an excited state of a two-photon absorption compound or photoreactive compound (giving electrons to a two-photon absorption compound or receiving electrons from a two-photon absorption compound) ) Or a radical generated by direct excitation to initiate radical polymerization of the polymerizable compound.
Among the above, the following systems are polymerization initiator systems that can activate radical polymerization.
1) Ketone polymerization initiator 2) Organic peroxide polymerization initiator 3) Bisimidazole polymerization initiator 4) Trihalomethyl-substituted triazine polymerization initiator 5) Diazonium salt polymerization initiator 6) Diaryliodonium salt polymerization Initiator 7) sulfonium salt polymerization initiator 8) borate polymerization initiator 9) diaryliodonium organic boron complex polymerization initiator 10) sulfonium organic boron complex polymerization initiator 11) metal arene complex polymerization initiator

More preferably as a polymerization initiator capable of activating radical polymerization,
1) ketone polymerization initiator 3) bisimidazole polymerization initiator 4) trihalomethyl-substituted triazine polymerization initiator 6) diaryliodonium salt polymerization initiator 7) sulfonium salt polymerization initiator, more preferably
3) Bisimidazole polymerization initiator 6) Diaryliodonium salt polymerization initiator 7) Sulfonium salt polymerization initiator.

  A polymerization initiator capable of activating only cationic polymerization refers to an acid (Bronsted acid or a non-radical generated by direct energy excitation or energy transfer or electron transfer from an excited state of a two-photon absorption compound or a photoreactive compound. It is a polymerization initiator capable of generating a Lewis acid and initiating cationic polymerization of the polymerizable compound with the acid.

Among the above systems, the following systems are polymerization initiator systems that can activate only cationic polymerization.
12) Sulfonic acid ester polymerization initiator

  Examples of the cationic polymerization initiator include “UV curing; science and technology (UV CURING; SCIENCE AND TECHNOLOGY)” [p. 23-76, S.M. Edited by S. PETER PAPPAS, A TECHNOLOGY MaRKETING PUBLICATION] and “Comments Inorg. Chem.” [B. Klingelt, M.M. Reedy Car and A. Rolov (B. KLINGERT, M. RIEDICER and A. ROLOFF), Vol. 3, p109-138 (1988)] and the like can also be used.

  A polymerization initiator capable of simultaneously activating radical polymerization and cationic polymerization is a radical or acid (Bronsted acid or radical) by energy transfer or electron transfer from the excited state of a two-photon absorption compound or photoreactive compound, or by direct excitation. Lewis acid) is a polymerization initiator that can simultaneously generate radical polymerization of a polymerizable compound by generated radicals and can initiate cationic polymerization of the polymerizable compound by generated acids.

Among the above systems, the following systems are polymerization initiator systems that can simultaneously activate radical polymerization and cationic polymerization.
4) Trihalomethyl-substituted triazine polymerization initiator 5) Diazonium salt polymerization initiator 6) Diaryliodonium salt polymerization initiator 7) Sulfonium salt polymerization initiator 13) Metal arene complex polymerization initiator

As a polymerization initiator that can activate radical polymerization and cationic polymerization,
6) Diaryliodonium salt polymerization initiators 7) Sulfonium salt polymerization initiators.

Next, the anionic polymerization initiator of the present invention will be described. The anionic polymerization initiator of the present invention is preferably a base generator capable of initiating anionic polymerization by generating a base (Bronsted base or Lewis base).
In this case, the base generator is a compound capable of generating a base by energy transfer or electron transfer from an excited state of a two-photon absorption compound or a photoreactive compound, or by direct excitation. The base generator is preferably stable in the dark. The base generator in the present invention is preferably a compound capable of generating a base by electron transfer from an excited state of a two-photon absorption compound or a photoreactive compound.
The base generator of the present invention preferably generates a Bronsted base by light, more preferably generates an organic base, and particularly preferably generates an amine as the organic base.

  The base generator of the present invention is preferably represented by the general formulas (31-1) to (31-4). In addition, you may use these base generators as 2 or more types of mixtures by arbitrary ratios as needed.

In the general formula (31-1) or (31-2), R ₂₀₁ and R ₂₀₂ each independently represent a hydrogen atom, an alkyl group (preferably 1 to 20 carbon atoms (hereinafter referred to as C number), for example, methyl, Ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, n-octadecyl, benzyl, 3-sulfopropyl, 4-sulfobutyl, carboxymethyl, 5-carboxypentyl), an alkenyl group (preferably having 2 to 20 carbon atoms) , For example, vinyl, allyl, 2-butenyl, 1,3-butadienyl), a cycloalkyl group (preferably C 3-20, such as cyclopentyl, cyclohexyl), an aryl group (preferably C 6-20, such as phenyl 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl, 2-naphthyl), heterocyclic group Preferably it represents any one of C 1-20, for example, pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, pyrrolidino, piperidino, morpholino), more preferably a hydrogen atom, an alkyl group, a cycloalkyl group, Preferably, it represents a hydrogen atom, a methyl group, an ethyl group, a cyclohexyl group, or a cyclopentyl group.
R ₂₀₁ and R ₂₀₂ may be linked to each other to form a ring, and the heterocycle formed is preferably a piperidine ring, a pyrrolidine ring, a piperazine ring, a morpholine ring, a pyridine ring, a quinoline ring, or an imidazole ring, and more A piperidine ring, a pyrrolidine ring and an imidazole ring are preferable, and a piperidine ring is most preferable.
As a more preferable combination of R ₂₀₁ and R ₂₀₂ , R ₂₀₁ may be a substituted cyclohexyl group, R ₂₀₂ is a hydrogen atom, R ₂₀₁ may be a substituted alkyl group, R ₂₀₂ is a hydrogen atom, R ₂₀₁ , R _{202 202} may be linked to form a piperidine ring or an imidazole ring.

  In General Formula (31-1) or (31-2), n201 is 0 or 1, preferably 1.

In the general formula (31-1), R ₂₀₃ each independently represents a substituent, and preferred examples of the substituent include an alkyl group (preferably having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, Isopropyl, n-butyl, n-pentyl, benzyl, 3-sulfopropyl, 4-sulfobutyl, carboxymethyl, 5-carboxypentyl), alkenyl group (preferably having 2 to 20 carbon atoms, for example, vinyl, allyl, 2-butenyl 1,3-butadienyl), a cycloalkyl group (preferably having 3 to 20 carbon atoms, such as cyclopentyl, cyclohexyl), an aryl group (preferably having 6 to 20 carbon atoms, such as phenyl, 2-chlorophenyl, 4-methoxyphenyl, 3-methylphenyl, 1-naphthyl), a heterocyclic group (preferably having 1 to 20 carbon atoms such as pyridyl, thie , Furyl, thiazolyl, imidazolyl, pyrazolyl, pyrrolidino, piperidino, morpholino), alkynyl group (preferably having 2 to 20 carbon atoms, such as ethynyl, 2-propynyl, 1,3-butadiynyl, 2-phenylethynyl), halogen atom (For example, F, Cl, Br, I), an amino group (preferably C 0-20, for example, amino, dimethylamino, diethylamino, dibutylamino, anilino), a cyano group, a nitro group, a hydroxyl group, a mercapto group, Carboxyl group, sulfo group, phosphonic acid group, acyl group (preferably C 1-20, for example, acetyl, benzoyl, salicyloyl, pivaloyl), alkoxy group (preferably C 1-20, for example, methoxy, butoxy, cyclohexyl) Oxy), an aryloxy group (preferably C number) To 26, for example, phenoxy, 1-naphthoxy), alkylthio group (preferably having 1 to 20 carbon atoms, for example, methylthio, ethylthio), arylthio group (preferably having 6 to 20 carbon atoms, for example, phenylthio, 4-chlorophenylthio) , Alkylsulfonyl groups (preferably having 1 to 20 carbon atoms, such as methanesulfonyl and butanesulfonyl), arylsulfonyl groups (preferably having 6 to 20 carbon atoms, such as benzenesulfonyl and paratoluenesulfonyl), sulfamoyl groups (preferably C number 0-20, for example, sulfamoyl, N-methylsulfamoyl, N-phenylsulfamoyl), carbamoyl group (preferably C number 1-20, for example, carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl) N-phenylcarbamoyl), An acylamino group (preferably having 1 to 20 carbon atoms such as acetylamino, benzoylamino), an imino group (preferably having 2 to 20 carbon atoms such as phthalimino), an acyloxy group (preferably having 1 to 20 carbon atoms such as acetyloxy, benzoyl) Oxy), alkoxycarbonyl group (preferably C 2-20, such as methoxycarbonyl, phenoxycarbonyl), carbamoylamino group (preferably C 1-20, such as carbamoylamino, N-methylcarbamoylamino, N-phenylcarbamoyl) Amino), and more preferably an alkyl group, an aryl group, a heterocyclic group, a halogen atom, an amino group, a cyano group, a nitro group, a carboxyl group, a sulfo group, an alkoxy group, an alkylthio group, an arylsulfonyl group, a sulfamoyl group. , Carbamoy Group, an alkoxycarbonyl group.

In the general formula (31-1), R ₂₀₃ is preferably a nitro group or an alkoxy group, more preferably a nitro group or a methoxy group, and most preferably a nitro group.
In General Formula (31-1), n202 is an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2. When n202 is 2 or more, a plurality of R ₂₀₃ may be the same or different, and may be linked to form a ring. Preferred examples of the ring formed include a benzene ring and a naphthalene ring.
In the general formula (31-1), when R ₂₀₃ is a nitro group, it is preferably substituted at the 2-position or 2,6-position, and when R ₂₀₃ is an alkoxy group, it is substituted at the 3, 5-position Is preferred.

In the general formula (31-1), R ₂₀₄ and R ₂₀₅ each independently represents a hydrogen atom or a substituent (preferably the same as the examples of the substituent mentioned in R ₃ as the substituent) _. The hydrogen atom, an alkyl group, or an aryl group, and more preferably any one of a hydrogen atom, a methyl group, and a 2-nitrophenyl group.
A more preferable combination of _{R 204, R 205, R 204} , R 205 both hydrogen atom, R ₂₀₅ R ₂₀₄ is a methyl group is a hydrogen atom, R _204, R ₂₀₅ both methyl, R ₂₀₄ is a 2-nitrophenyl group R ₂₀₅ is a hydrogen atom, and the like, more preferably R ₂₀₄ and R _{205 are} co-hydrogen atoms.

In the general formula (31-2), R ₂₀₆ and R ₂₀₇ each represent a substituent (preferably the same as the substituents exemplified in R ₂₀₃ as the substituent), preferably an alkoxy group, an alkylthio group, nitro Group and an alkyl group, and more preferably a methoxy group.
In General Formula (31-2), n203 and n204 each independently represents an integer of 0 to 5, and preferably represents an integer of 0 to 2. When n203 and n204 are 2 or more, a plurality of R ₂₀₆ and R ₂₀₇ may be the same or different and may be linked to form a ring. Preferred examples of the ring formed include a benzene ring and a naphthalene ring. .
In general formula (31-2), R ₂₀₆ is more preferably an alkoxy group substituted at the 3,5-position, and even more preferably a methoxy group substituted at the 3,5-position.

In the general formula (31-2), R ₂₀₈ represents a hydrogen atom or a substituent (preferably the same as the substituent described in R ₂₀₃ as the substituent), preferably a hydrogen atom or an aryl group, More preferably, it is a hydrogen atom.

In the general formula (31-3), R ₂₀₉ represents a substituent (preferably the same as the examples of the substituent mentioned in R ₂₀₃ as the substituent), preferably an alkyl group, an aryl group, a benzyl group, an amino group. And more preferably an alkyl group which may be substituted, a t-butyl group, a phenyl group, a benzyl group, an anilino group which may be substituted, or a cyclohexylamino group.
The compound represented by the general formula (31-3) may be a compound in which R ₂₀₉ is linked to a polymer chain.

In the general formula (31-3), R ₂₁₀ and R ₂₁₁ each independently represent a hydrogen atom or a substituent (preferably the same as the substituents exemplified in R ₂₀₃ as the substituent), preferably an alkyl group Or an aryl group is represented, More preferably, a methyl group, a phenyl group, and 2-naphthyl group are represented.
R ₂₁₀ and R ₂₁₁ may _combine with each other to form a ring, and the ring formed is preferably, for example, a fluorene ring.

In General Formula (31-4), R ₂₁₂ represents an aryl group or a heterocyclic group, and more preferably the following aryl group or heterocyclic group.

In formula (31-4), R ₂₁₃ , R ₂₁₄ and R ₂₁₅ are each independently a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group or a heterocyclic group (preferred examples are R ₂₀₁ , R _The same as ₂₀₂ ), preferably an alkyl group, more preferably a butyl group. R ₂₁₃ , R ₂₁₄ , and R ₂₁₅ may be linked to each other to form a ring, and preferably a hetero ring formed is preferably a piperidine ring, a pyrrolidine ring, a piperazine ring, a morphophore ring, a pyridine ring, a quinoline ring, or an imidazole. A ring, more preferably a piperidine ring, a pyrrolidine ring, and an imidazole ring.

In the general formula (31-4), R ₂₁₆ , R ₂₁₇ , R ₂₁₈ and R ₂₁₉ each independently represents an alkyl group or an aryl group, R ₂₁₆ , R ₂₁₇ and R ₂₁₈ are phenyl groups, and R ₂₁₉ is It is more preferably an n-butyl group or a phenyl group.

  The base generator of the present invention is preferably represented by the general formula (31-1) or (31-3), and more preferably represented by the general formula (31-1).

  Although the preferable specific example of the base generator of this invention is shown below, this invention is not limited to this.

In the two-photon absorption optical recording material of the present invention, a binder is preferably used.
The binder is usually used for the purpose of improving the film formability of the composition, the uniformity of the film thickness, and the stability during storage. As the binder, those having good compatibility with a liquid crystalline compound, a polymerization initiator, a photoreactive compound, a two-photon absorption compound and the like are preferable.

  As the binder, a solvent-soluble thermoplastic polymer is preferable and can be used alone or in combination with each other.

  The binder has a reactive site and may be cross-linked or hardened by reacting with a cross-linking agent, a polymerizable monomer or an oligomer. In this case, the reactive site includes an ethylenically unsaturated group represented by an acrylic group and a methacryl group as a radical reactive site, an oxirane compound, an oxetane compound, a vinyl ether group as a cationic reactive site, and a carboxyl group as a condensation polymerization reaction site. Preferred are acids, alcohols, amines and the like.

Preferred binders for use in the present invention include, for example, acrylate and alpha-alkyl acrylate esters and acidic polymers and interpolymers (eg, polymethyl methacrylate and polyethyl methacrylate, methyl methacrylate and other (meth) acrylic acid alkyl esters). Polymers), polyvinyl esters (eg, polyvinyl acetate, polyacetic acid / vinyl acrylate, polyacetic acid / vinyl methacrylate and hydrolyzable polyvinyl acetate), ethylene / vinyl acetate copolymers, saturated and unsaturated polyurethanes, butadiene And isoprene polymers and copolymers and polyglycols having a weight average molecular weight of approximately 4,000 to 1,000,000, high molecular weight poly (ethylene oxide), epoxides (eg epoxies having acrylate or methacrylate groups) Compound), polyamide (for example, N-methoxymethyl polyhexamethylene adipamide), cellulose ester (for example, cellulose acetate, cellulose acetate succinate and cellulose acetate butyrate), cellulose ether (for example, methyl cellulose, ethyl cellulose, ethyl benzyl cellulose) ), Polycarbonate, polyvinyl acetal (polyvinyl butyral and polyvinyl formal), polyvinyl alcohol, polyvinyl pyrrolidone, acid-containing polymers and copolymers that function as suitable binders, in U.S. Pat. No. 3,458,311 and U.S. Pat. And those disclosed in US Pat. No. 273,857.
In addition, polystyrene polymers and copolymers such as acrylonitrile, maleic anhydride, acrylic acid, methacrylic acid and esters thereof, vinylidene chloride copolymers (eg vinylidene chloride / acrylonitrile copolymers, vinylidene chloride / methacrylate copolymers) Polymers, vinylidene chloride / vinyl acetate copolymer), polyvinyl chloride and copolymers (eg, polyvinyl chloride / acetate, vinyl chloride / acrylonitrile copolymer), polyvinyl benzal synthetic rubber (eg, butadiene / acrylonitrile copolymer) , Acrylonitrile / butadiene / styrene copolymer, methacrylate / acrylonitrile / butadiene / styrene copolymer, 2-chlorobutadiene-1,3 polymer, chlorinated rubber, styrene / butadiene / styrene, styrene / Isoprene / styrene block copolymer), copolyester (eg, polymethylene glycol of formula HO (CH ₂ ) nOH (where n is an integer from 2 to 10), and (1) hexahydroterephthalic acid, sebacin Acid and terephthalic acid, (2) terephthalic acid, isophthalic acid and sebacic acid, (3) terephthalic acid and sebacic acid, (4) produced from the reaction product of terephthalic acid and isophthalic acid, and (5) the glycol And (i) a mixture of terephthalic acid, isophthalic acid and sebacic acid and (ii) a copolyester prepared from terephthalic acid, isophthalic acid, sebacic acid and adipic acid), poly N-vinylcarbazole and copolymers thereof, and H . Examples include carbazole-containing polymers as disclosed in Kamogawa et al. In Journal of Polymer Science, Polymer Chemistry Edition, Vol. 18, pp. 9-18 (1979).

  A fluorine atom-containing polymer is also preferable as the low refractive index binder. Preferably, fluoroolefin is an essential component, and one or more selected from alkyl vinyl ether, alicyclic vinyl ether, hydroxy vinyl ether, olefin, haloolefin, unsaturated carboxylic acid and ester thereof, and carboxylic acid vinyl ester It is a polymer soluble in an organic solvent having the unsaturated monomer as a copolymerization component. Preferably, the weight average molecular weight is 5,000 to 200,000, and the fluorine atom content is 5 to 70% by mass.

  As the fluoroolefin in the fluorine atom-containing polymer, tetrafluoroethylene, chlorotrifluoroethylene, vinyl fluoride, vinylidene fluoride, or the like is used. In addition, as other copolymerization components, alkyl vinyl ethers include ethyl vinyl ether, isobutyl vinyl ether, n-butyl vinyl ether, alicyclic vinyl ethers such as cyclohexyl vinyl ether and derivatives thereof, hydroxy vinyl ethers such as hydroxybutyl vinyl ether, olefins and halo. Examples of olefins include ethylene, propylene, isobutylene, vinyl chloride, and vinylidene chloride. Examples of carboxylic acid vinyl esters include vinyl acetate and n-vinyl butyrate. Examples of unsaturated carboxylic acids and esters include (meth) acrylic acid and crotonic acid. Unsaturated carboxylic acids and methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, iso (meth) acrylate C1 to C18 alkyl esters of (meth) acrylic acid such as lopyr, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, hydroxyethyl (meth) C2-C8 hydroxyalkyl esters of (meth) acrylic acid such as acrylate, hydroxypropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, etc. Can be mentioned. These radical polymerizable monomers may be used alone or in combination of two or more, and if necessary, a part of the monomer may be used as another radical polymerizable monomer such as styrene, α -You may substitute with vinyl compounds, such as methylstyrene, vinyl toluene, and (meth) acrylonitrile. Further, as other monomer derivatives, carboxylic acid group-containing fluoroolefin, glycidyl group-containing vinyl ether, and the like can also be used.

  Specific examples of the fluorine atom-containing polymer include, for example, an organic solvent-soluble “Lumiflon” series having a hydroxyl group (for example, Lumiflon LF200, weight average molecular weight: about 50,000, manufactured by Asahi Glass Co., Ltd.). In addition, organic solvent-soluble fluorine atom-containing polymers are also marketed by Daikin Industries, Ltd., Central Glass Co., Ltd., and Penwort Co., Ltd., and these can also be used.

In addition, when the photoreactive compound mentioned above is a high molecular compound, it is also preferable to serve as a binder, and in that case, it is particularly preferable that the photoreactive compound is a pendant high molecular compound.
In that case, the binder is preferably used for controlling the orientation of the low-molecular liquid crystal.

  In the two-photon absorption optical recording material of the present invention, additives such as a polymerizable monomer, a polymerizable oligomer, a crosslinking agent, a heat stabilizer, a plasticizer, and a solvent can be used as necessary.

  Preferable examples of using a polymerizable monomer, a polymerizable oligomer, and a crosslinking agent in the two-photon absorption optical recording material of the present invention include those described in Japanese Patent Application No. 2003-82732.

In the two-photon absorption optical recording material of the present invention, it may be preferable to use a chain transfer agent. Preferred chain transfer agents are thiols such as 2-mercaptobenzoxazole, 2-mercaptobenzthiazole, 2-mercaptobenzimidazole, 4-methyl-4H-1,2,4-triazole-3-thiol, 4 , 4-thiobisbenzenethiol, p-bromobenzenethiol, thiocyanuric acid, 1,4-bis (mercaptomethyl) benzene, p-toluenethiol, etc., as described in USP No. 4414312 and JP-A No. 64-13144 Thiols, disulfides described in JP-A-2-291561, thiones described in USP 3,558,322 and JP-A 64-17048, O-acylthiohydroxamates and N-alkoxy described in JP-A-2-291560 Also included are pyridinethiones.
In particular, when the polymerization initiator is 2,4,5-triphenylimidazolyl dimer, it is preferable to use a chain transfer agent.
As for the usage-amount of a chain transfer agent, 1.0-30 mass% is preferable with respect to the whole composition.

  A heat stabilizer can be added to the two-photon absorption optical recording material of the present invention in order to improve the storage stability during storage.

  Useful heat stabilizers include hydroquinone, phenidone, p-methoxyphenol, alkyl and aryl substituted hydroquinones and quinones, catechol, t-butylcatechol, pyrogallol, 2-naphthol, 2,6-di-t-butyl-p. -Cresol, phenothiazine, chloranneal and the like. Also useful are dinitroso dimers described in US Pat. No. 4,168,982 to Pazos.

  The plasticizer is used to change the adhesion, flexibility, hardness, and other mechanical properties of the two-photon absorption optical recording material. Examples of the plasticizer include triethylene glycol dicaprylate, triethylene glycol bis (2-ethylhexanoate), tetraethylene glycol diheptanoate, diethyl sebacate, dibutyl suberate, tris (2-ethylhexyl) phosphate, Examples include tricresyl phosphate and dibutyl phthalate.

The ratio of each component in the two-photon absorption optical recording material of the present invention and the composition is generally preferably in the following% range based on the total mass of the composition.
Binder: preferably 0 to 95% by mass, more preferably 0 to 70% by mass,
Liquid crystalline compound: preferably 10 to 99% by mass, more preferably 30 to 99% by mass,
Photoreactive compound: preferably 0.1 to 30% by mass, more preferably 1 to 10% by mass
Polymerization initiator: preferably 0.1 to 20% by mass, more preferably 1 to 10% by mass
Two-photon absorption compound: preferably 0 to 10% by mass, more preferably 0.1 to 10% by mass

The two-photon absorption optical recording material of the present invention may be prepared by a usual method. For example, the above-mentioned essential components and optional components can be prepared as they are or by adding a solvent as necessary.
Examples of the solvent include ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, acetone and cyclohexanone, ester solvents such as ethyl acetate, butyl acetate, ethylene glycol diacetate, ethyl lactate and cellosolve acetate, carbonization such as cyclohexane, toluene and xylene. Hydrogen solvent, ether solvents such as tetrahydrofuran, dioxane, diethyl ether, cellosolv solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, dimethyl cellosolve, methanol, ethanol, n-propanol, 2-propanol, n-butanol, diacetone Alcohol solvents such as alcohol, fluorine solvents such as 2,2,3,3-tetrafluoropropanol, dichloromethane, chloroform, 1,2-dichloro Halogenated hydrocarbon solvents such as Roetan, N, an amide-based solvents such as N- dimethylformamide.

The two-photon absorption optical recording material of the present invention can be applied directly on the substrate by using a spin coater, roll coater or bar coater, or can be cast as a film and laminated on the substrate by a usual method. Thus, a two-photon absorption optical recording material can be obtained.
Here, “substrate” means any natural or synthetic support, preferably one that can exist in the form of a flexible or rigid film, sheet or plate.
Preferred examples of the substrate include polyethylene terephthalate, resin-primed polyethylene terephthalate, polyethylene terephthalate subjected to flame or electrostatic discharge treatment, cellulose acetate, polycarbonate, polymethyl methacrylate, polyester, polyvinyl alcohol, and glass.
The solvent used can be removed by evaporation during drying. Heating or reduced pressure may be used for evaporation removal.

  In the present invention, an alignment film may be used for the substrate in order to align the liquid crystalline compound. The alignment film may be rubbed or photo-aligned. Examples of the alignment film by rubbing include polyvinyl alcohol and polyimide. Examples of the alignment film by photo-alignment include those described in “Liquid Crystal” 1999, Vol. 3, page 3. Also, the so-called “command surface” described in “Applied Physics” 1993, 62, 998 and “Polymer Processing” 2000, 49, 50 can be used.

  Further, a protective layer for blocking oxygen may be formed on the two-photon absorption optical recording material. The protective layer is made of a plastic film or plate such as polyolefin such as polypropylene or polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyethylene terephthalate or cellophane film by electrostatic adhesion or lamination using an extruder. Alternatively, the polymer solution may be applied. Further, a glass plate may be bonded. Further, an adhesive or a liquid substance may be present between the protective layer and the photosensitive film and / or between the base material and the photosensitive film in order to improve airtightness.

When the two-photon absorption optical recording material of the present invention is used for a three-dimensional optical recording medium, the two-photon absorption optical recording material is improved in the S / N ratio during signal reproduction when shrinkage does not occur before and after the two-photon absorption optical recording. This is more preferable.
Therefore, for example, an expansion agent described in JP-A No. 2000-86914 is used for the two-photon absorption optical recording material of the present invention, or shrink resistance resistance described in JP-A Nos. 2000-250382, 2000-172154, and JP-A No. 11-344917 is used. It is also preferable to use a certain binder.

  When the two-photon absorption optical recording material of the present invention is used for an optical recording medium, the two-photon absorption optical recording material is preferably stored in a light shielding cartridge during storage.

As described above, the two-photon absorption optical recording material of the present invention is a compound having an intrinsic birefringence at the laser focus (recording) portion by using the highly efficient two-photon absorption compound of the present invention, preferably Can change the orientation of a low-molecular liquid crystalline compound having a polymerizable group with high efficiency by two-photon absorption and can be fixed as it is.
Since two-photon absorption is used for recording, the refractive index can be three-dimensionally modulated by changing the orientation in the laser focus (recording) and non-focus (non-recording) areas, and as a result, the light reflectance can be changed. Thus, it can be applied to a three-dimensional optical recording medium and a recording / reproducing method thereof by a method that cannot be rewritten. Therefore, it is excellent in nondestructive reproduction and storage as compared with a rewritable method.

[Example]
Hereinafter, specific embodiments of the present invention will be described based on experimental results. Of course, the present invention is not limited to these examples.

  Synthesis of the two-photon absorption compound of the present invention

(1) Synthesis of D-73

  The two-photon absorption compound D-73 of the present invention can be synthesized by the following method.

  14.3 g (40 mmol) of the quaternary salt [1] was dissolved in 50 ml of water, 1.6 g (40 mmol) of sodium hydroxide was added, and the mixture was stirred at room temperature for 30 minutes. The mixture was extracted three times with ethyl acetate, dried over magnesium sulfate and concentrated to obtain 9.2 g (yield 100%) of methylene-based [2] oil.

  3.97 g (40 mmol) of dimethylaminoacrolein [3] was dissolved in 50 ml of acetonitrile, and 6.75 g (44 mmol) of phosphorus oxychloride was added dropwise while cooling to 0 ° C., followed by stirring at 0 ° C. for 10 minutes. Subsequently, 9.2 g of acetonitrile solution of methylene base [2] was dropped, and the mixture was stirred at 35 ° C. for 4 hours. After pouring into 100 ml of ice water, 16 g of sodium hydroxide was added and refluxed for 10 minutes. After cooling, the mixture was extracted 3 times with ethyl acetate, dried over magnesium sulfate and concentrated. Purification by silica gel column chromatography (developing solvent: ethyl acetate: hexane = 1: 10 → 1: 3) gave 4.4 g (39% yield) of aldehyde [4] as an oil.

  0.126 g (1.5 mmol) of cyclopentanone and 0.85 g (3 mmol) of aldehyde [4] were dissolved in 30 ml of dehydrated methanol and refluxed in a dark atmosphere in a nitrogen atmosphere. After becoming uniform, 0.69 g (3.6 mmol) of a 28% sodium methoxide methanol solution was added, and the mixture was further refluxed for 6 hours. After cooling, the precipitated crystals were separated by filtration and washed with methanol to obtain 0.50 g (yield 54%) of D-73 dark green crystals. The structure was confirmed by NMR spectrum, MS spectrum and elemental analysis.

(2) Synthesis of D-84

  The two-photon absorption compound D-84 of the present invention can be synthesized by the following method.

  33.6 g (0.4 mol) of cyclopentanone, 2 ml of DBN, and 400 g of N, N-dimethylformamide dimethyl acetal were refluxed for 5 days. After concentration, acetone was added and the mixture was cooled to separate the crystals. The crystals were washed with cold acetone to obtain 32.4 g of crystals [5] (42% yield).

[5] 0.78 g (4 mmol), quaternary salt [6] 2.78 g (8 mmol) and 20 ml of pyridine were refluxed in a dark place under a nitrogen atmosphere for 4 hours. After cooling, ethyl acetate was added and the crystals were separated and washed with ethyl acetate. The crystals were dispersed in methanol and separated by filtration to obtain 2.14 g (yield 56%) of the desired deep blue crystals of D-84.
The structure was confirmed by NMR spectrum, MS spectrum and elemental analysis.

  In addition, other two-photon absorption compounds represented by the general formula (1) of the present invention can be synthesized by the synthesis methods of D-73 and D-84, Tetrahedron. Lett. 42, 6129, (2001) and the like.

  Further, other cyanine dyes, merocyanine dyes, oxonol dyes and the like are also described in F.I. M.M. By Harmer, Heterocyclic Compounds-Cyanine Dies and Related Compounds, John & Wiley & Sons, New York, London, 1964, D.C. M.M. According to Sturmer, Heterocyclic Compounds-Special Topics in Heterocyclic Chemistry, Chapter 18, Section 14, pages 482 to 515, according to John & Wiley & Sons, New et al.

[Evaluation of Refractive Index Modulation Recording by Controlling Two-Photon Absorption Orientation of Low Molecular Liquid Crystalline Compound Having Polymerizable Group]

Next, the two-photon absorption optical recording material and the two-photon optical recording method of the present invention will be described in detail.
Two-photon absorption compound D-128 1% by mass in a dark room, photoreactive compound R-2, 5% by mass, polymerization initiator o-Cl-HABI, 1.8% by mass, 2-mercaptobenzoxazole 1.2 A two-photon absorption optical recording material 101 was prepared by dissolving 91% by mass of 91% by mass of a liquid crystalline compound LC-22 having a polymerizable group in 300% by mass of chloroform.
The two-photon absorption optical recording material 101 was applied to a glass substrate using an applicator so as to have a thickness of about 10 μm to form a photosensitive layer, and then heated and dried at 40 ° C. for 3 minutes to distill off the solvent. Further, the two-photon absorption optical recording material 101 was produced by covering the photosensitive layer with a glass substrate.

For the performance evaluation of the two-photon absorption polymerizable composition of the present invention, a Ti: sapphire pulse laser (pulse width: 100 fs, repetition: 80 MHz, average output: 1 W, peak power: 100 kW) that can be measured in the wavelength range of 700 nm to 1000 nm. ), The two-photon absorption polymerizable composition of the present invention was irradiated with the laser beam condensed with a na0.6 lens.
The irradiation wavelength used was around the wavelength at which the two-photon absorption cross section δ was maximum in a 10 ⁻⁴ M solution of the two-photon absorption compound.
The sample 101 was irradiated with 720 nm laser light while heating the two-photon recording material at 45 ° C. to cause two-photon absorption. Based on the orientation change at the laser focal point (recording part) of the light irradiation part. Refractive index change and polymerization are observed. Further, by scanning the laser focus position in the horizontal and depth directions, it is possible to cause refractive index modulation and polymerization due to orientation change at an arbitrary place in the three-dimensional direction.
Furthermore, when visible light to ultraviolet light is irradiated on the entire surface with a xenon lamp at room temperature, it can be confirmed that the recording can be fixed by the entire surface polymerization while being preserved, and further recording cannot be performed even if rewriting is attempted thereafter. In addition, since the recorded hologram does not disappear even when the recorded hologram is heated or exposed to the entire surface, it can be confirmed that the recording can be stored well.
When the recorded two-photon absorption recording material is irradiated with a 740 nm laser, a difference in reflectance due to a difference in refractive index can be confirmed between the recording portion and the non-recording portion.

  In an advanced information society, it is expected to be used as a three-dimensional optical recording medium capable of achieving ultra-high density and ultra-high capacity recording.

Claims (12)

A two-photon absorption optical recording method characterized in that an orientation change of a compound having an intrinsic birefringence is caused by two-photon absorption, and is recorded as a refractive index modulation by a non-rewritable method by fixing it by a chemical reaction as it is. 2. The two-photon absorption optical recording method according to claim 1, wherein the compound having an intrinsic birefringence has a polymerizable group and is fixed by polymerization. 3. The two-photon absorption optical recording method according to claim 1, wherein the compound having an intrinsic birefringence is a liquid crystal compound. A two-photon absorption optical recording material comprising at least a low-molecular liquid crystalline compound having a polymerizable group, a photoreactive compound, a polymerization initiator, and a two-photon absorption compound, and a non-rewritable method.
However, the photoreactive compound and the two-photon absorption compound may be the same compound or different compounds. The photoreactive compound reacts and cannot be rewritten by electron transfer or energy transfer from an excited state generated by absorption of the two-photon absorption exposure by the two-photon absorption compound. A two-photon absorption optical recording method. The two-photon absorption recording material according to claim 4, wherein the two-photon absorption compound is a cyanine dye, a merocyanine dye, an oxonol dye, a phthalocyanine dye, or a compound represented by the following general formula (1).
General formula (1)

In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a substituent, and some of R ¹ , R ² , R ³ and R ⁴ are bonded to each other to form a ring. May be formed. n and m each independently represent an integer of 0 to 4, and when n and m are 2 or more, a plurality of R ¹ , R ² , R ³ and R ⁴ may be the same or different. However, n and m are not 0 simultaneously. X ¹ and X ² independently represent an aryl group, a heterocyclic group, or a group represented by General Formula (2).
General formula (2)

In the formula, R ⁵ represents a hydrogen atom or a substituent, R ⁶ represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group, and Z ¹ represents an atomic group forming a 5- or 6-membered ring. . 7. The two-photon absorption optical recording material according to claim 4, wherein the photoreactive compound is a photoisomerizable compound. The photoreactive compound is selected from azobenzene compounds, stilbene compounds, spiropyran compounds, spirooxazine compounds, diarylethene compounds, fulgide compounds, fulgimide compounds, cinnamic acid compounds, coumarin compounds and chalcone compounds. The two-photon absorption optical recording material according to claim 4, wherein the two-photon absorption optical recording material is any one of the compounds. 9. The two-photon absorption optical recording material according to claim 4, wherein the photoreactive compound is a polymer compound in which a photoreactive site is pendant. 10. The low-molecular liquid crystalline compound having a polymerizable group is any compound selected from a nematic liquid crystalline compound, a smectic liquid crystalline compound, a discotic nematic liquid crystalline compound, a discotic liquid crystalline compound, and a cholesteric liquid crystalline compound. The two-photon absorption optical recording material according to any one of claims 4 and 6, wherein the two-photon absorption optical recording material is characterized. 6. The two-photon absorption optical recording method according to claim 3, wherein, when performing optical recording by two-photon absorption, the two-photon absorption optical recording is performed at a temperature at which the liquid crystalline compound is in a liquid crystal state. An optical recording medium using the two-photon absorption optical recording material according to any one of claims 4 and 6.