JP2005275158A - Hologram recording material, hologram recording method, and optical recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hologram recording material and hologram recording system which can realize high sensitivity, high diffraction efficiency, good preservable property, low shrinkage degree, and dry processing and which are applicable to a high-density recording medium, three-dimensional display, holographic optical element, etc. <P>SOLUTION: The hologram recording material contains at least one dyestuff having a polymerizable group. The hologram recording material is preferably not subjected to wet processing. The hologram recording material is preferably a system which is not rewritable. The system which is not rewritable means a system in which data is recorded by an irreversible reaction and the once recorded data can be saved without rewriting even if an attempt is made to rewrite the data by overwriting and recording. The system is therefore suitable for saving of the important data required to be saved for a long period of time. Needless to say, however, it is possible to freshly additionally write and successively record the data in a not yet recorded region. In such a sense, the recording medium is generally called "DRAW (Direct-Read-and-After Write) type" or "write once" type. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hologram recording material and a hologram recording method applicable to a high-density optical recording medium, a three-dimensional display, a holographic optical element, and the like.

  General principles relating to hologram production are described in chapter 2 of several literatures and technical books such as “Holographic Display” (Junpei Uchinai, Sangyo Tosho [Non-Patent Document 1]). According to these, the photosensitive hologram recording material is placed at a position where one of the two light fluxes of the coherent laser light is irradiated onto the recording object and the total reflection light from the recording object can be received. The hologram recording material is directly irradiated with the other coherent light in addition to the reflected light from the object without hitting the object. Reflected light from the object is referred to as object light, and light directly applied to the recording material is referred to as reference light, and interference fringes between the reference light and object light are recorded as image information. Next, when the processed recording material is irradiated with the same light (reproduction illumination light) as the reference light, it is diffracted by the hologram so as to reproduce the wavefront of the reflected light that first reaches the recording material from the object during recording. As a result, an object image substantially the same as the real image of the object can be observed three-dimensionally.

A hologram formed by causing the reference light and the object light to enter the hologram recording material from the same direction is called a transmission hologram. The interference fringes are formed at intervals of about 1000 to 3000 per 1 mm in a form perpendicular or nearly perpendicular to the recording material film surface direction.
On the other hand, holograms formed by being incident on opposite sides of the hologram recording material are generally called reflection holograms. The interference fringes are formed at intervals of about 3000 to 7000 per 1 mm in a shape parallel or nearly parallel to the recording material film surface direction.
The transmission hologram can be created by a known method as disclosed in, for example, JP-A-6-43634 [Patent Document 1]. The reflection hologram can be created by a known method disclosed in, for example, JP-A-2-3082 [Patent Document 2] and JP-A-3-50588 [Patent Document 3].

On the other hand, a hologram whose film thickness is sufficiently thick with respect to the interference fringe interval (usually a thickness of about 5 times the interference fringe interval or about 1 μm or more) is called a volume hologram.
On the other hand, a hologram whose film thickness is about 5 times or less of the interference fringe interval or about 1 μm or less is called a planar type or a surface type.

  Further, a hologram that records interference fringes by absorption of a dye or silver is called an amplitude hologram, and a hologram that is recorded by surface relief or refractive index modulation is called a phase hologram. Amplitude holograms are not preferred in terms of light utilization efficiency because light diffraction efficiency or reflection efficiency is significantly reduced due to light absorption, and phase holograms are usually preferred.

In a volume phase hologram, the phase of light can be modulated without absorbing light by forming many interference fringes with different refractive indexes in the hologram recording material instead of optical absorption.
In particular, reflective volume phase holograms, also called Lippmann holograms, are capable of full color, white reproduction and high resolution with high diffraction efficiency due to wavelength selective reflection by black diffraction, and high resolution full color 3D display. Can be provided.
Recently, taking advantage of the wavelength selective reflection, a hologram optical element represented by a head-up display (HUD) mounted on an automobile, a pickup lens for an optical disk, a head-mounted display, a color filter for liquid crystal, a reflective liquid crystal reflector, and the like. (HOE) has been widely put into practical use.
In addition, for example, practical use or application is being studied for lenses, diffraction gratings, interference filters, optical fiber couplers, facsimile light polarizers, architectural window glass, and the like.

By the way, in the recent trend of advanced information society, networks such as the Internet and high-definition TVs are rapidly spreading. In addition, HDTV (High Definition Television) will soon be broadcast, and there is an increasing demand for a high-density recording medium for easily and inexpensively recording image information of 100 GB or more in consumer use.
Furthermore, in the trend of increasing computer capacity, there is a need for ultra-high-density recording media that can record large volumes of information of about 1 TB or more at high speed and low cost for business use such as computer backup and broadcast backup. It has been.
Under such circumstances, a compact, inexpensive optical recording medium that is replaceable and randomly accessible has attracted more attention than a magnetic tape medium that cannot be randomly accessed and a hard disk that is not replaceable and easily failed. However, an existing two-dimensional optical recording medium such as a DVD-R has a recording capacity of about 25 GB at most even if the recording / reproducing wavelength is shortened on the physical principle, and has a sufficiently large recording capacity to meet future requirements. The situation cannot be expected.

  Therefore, a three-dimensional optical recording medium that performs recording in the film thickness direction has attracted attention as the ultimate ultra-high density recording medium. As a promising method, there are a method using a two-photon absorption material and a method using holography (interference). Therefore, a volume phase hologram recording material has recently attracted attention as a three-dimensional optical recording medium (holographic memory). It became so.

  In a holographic memory using a volume phase hologram recording material, two-dimensional digital information (referred to as signal light) using a spatial light modulation element (SLM) such as DMD or LCD instead of object light reflected from a three-dimensional object. Will be recorded a lot. At the time of recording, multiplex recording such as angle multiplexing, phase multiplexing, wavelength multiplexing, and shift multiplexing is performed, so that the capacity can be increased to 1 TB. In addition, a CCD, CMOS, or the like is usually used for reading, and the parallel transfer and reading thereof can increase the transfer rate up to 1 Gbps.

However, the requirements for hologram recording materials used for holographic memories are more severe than those for three-dimensional displays and HOE applications as described below.
(1) High sensitivity (2) High resolution (3) High hologram diffraction efficiency (4) Recording process is dry and quick (5) Multiple recording is possible (Wide dynamic range)
(6) Shrinkage after recording is small (7) Hologram storage stability is good

  In particular, (1) high sensitivity, (3) high diffraction efficiency, (4) dry processing, (6) low shrinkage after recording, and (7) good storage stability. These are physical properties that are contradictory in chemical terms, and it is extremely difficult to achieve both.

  Here, as a known volume phase hologram recording material, a dichromate gelatin method, a bleached silver halide salt method, a photopolymer method, and the like are known as a write-once method, and a photorefractive method and a photochromic polymer as a rewritable method. Methods are known.

However, in these known volume phase hologram recording materials, particularly in the application to high-sensitivity optical recording media, materials that satisfy all of the required requirements are still desired and improvements are desired.
Specifically, for example, the dichromated gelatin method has the advantages of high diffraction efficiency and low noise characteristics, but has extremely poor storage stability, requires wet processing and has low sensitivity, and is suitable for holographic memory applications. Not suitable.
The bleached silver halide method has the advantage of high sensitivity, but it requires wet processing, is complicated in bleaching processing, has problems of large scattering and poor light resistance, and is used for holographic memory applications. After all it is not generally suitable.
Although the photorefractive material has the advantage that it can be rewritten, it has a problem that a high electric field needs to be applied at the time of recording and the record storage stability is poor.
Although the photochromic polymer system represented by azobenzene polymer material has the advantage that it can be rewritten, it has a problem that the sensitivity is very low and the storage stability is poor. For example, WO9744365A1 [Patent Document 4] presents a rewritable hologram recording material using refractive index anisotropy and orientation control of an azobenzene polymer (photochromic polymer). Although the yield is low and the system is accompanied by a change in orientation, the sensitivity is extremely low, and there is a problem in that the record storability is poor due to the contradiction of being rewritable, which is far from practical use.

Under such circumstances, the dry-processed photopolymer method disclosed in Patent Documents 1 to 3 described above has a binder, a radical polymerizable monomer, and a photopolymerization initiator as a basic composition, and a binder or We have devised a difference in refractive index by using a compound having an aromatic ring or chlorine or bromine on one of the radically polymerizable monomers, and as a result, in the bright part of the interference fringes formed during hologram exposure The monomer can form a refractive index difference by polymerization while the binder gathers in the dark part. Therefore, it can be said that it is a relatively practical method that can achieve both high diffraction efficiency and dry processing.
However, compared with the bleached silver halide method, the sensitivity is about 1/1000, the heat fixing treatment is required for nearly 2 hours in order to increase the diffraction efficiency, and radical polymerization, so that the polymerization inhibition by oxygen is inhibited. In addition, there is a problem that the diffraction wavelength and angle at the time of reproduction change due to the shrinkage of the recording material after exposure and fixing, the lack of storage stability due to the soft film, etc. Therefore, it cannot withstand use as a holographic memory application.

Here, in general, cationic polymerization, particularly cationic polymerization accompanied by ring opening of an epoxy compound or the like with respect to radical polymerization has little shrinkage after polymerization and is not subjected to polymerization inhibition by oxygen, and gives a rigid film. Therefore, some point out that cationic polymerization is more suitable for holographic memory applications.
For example, in JP-A-5-107999 [Patent Document 5] and JP-A-8-16078 [Patent Document 6], a cationically polymerizable compound (monomer or oligomer) is used instead of a binder, and further a sensitizing dye, radical A hologram recording material in which a polymerization initiator, a cationic polymerization initiator, and a radical polymerizable compound are combined is disclosed.

Further, JP-A-2001-523842 [Patent Document 7], JP-A-11-512847 [Patent Document 8] and the like disclose that a sensitizing dye, a cationic polymerization initiator, a cationic polymerizable compound, and a binder are used without using radical polymerization. A hologram recording material using only is disclosed.
However, although these cation polymerization methods show improvement in shrinkage rate compared to radical polymerization methods, the contradiction is that the sensitivity is lowered, and it is considered that this will be a big problem in terms of transfer speed in practical use. . In addition, the diffraction efficiency is lowered, which is considered to be a problem in terms of S / N ratio and multiple recording.

Therefore, in order to apply hologram recording materials to holographic memory, such a problem has been drastically solved, and in particular, it is completely new that can achieve both high sensitivity and low shrinkage, good storage, dry processing, and multiple recording characteristics. Development of a recording system has been strongly desired.
"Holographic Display", Junpei Uchiuchi, Industrial Books JP-A-6-43634 JP-A-2-3082 Japanese Patent Laid-Open No. 3-50588 WO9744365A1 publication Japanese Patent Laid-Open No. 5-107999 JP-A-8-16078 Special table 2001-523842 Special table 11-512847

  Therefore, the object of the present invention is to achieve both high sensitivity and high diffraction efficiency, good storability, low shrinkage, and dry processing applicable to high-density optical recording media, three-dimensional displays, holographic optical elements, and the like. A hologram recording material and a hologram recording method are provided.

  As a result of intensive studies by the inventors, the object of the present invention has been achieved by the following means.

(1) A hologram recording material comprising at least one dye having a polymerizable group.
(2) In the absorption spectrum of the dye having a polymerizable group, it has λmax which is 10 to 200 nm shorter than the hologram reproduction wavelength, ε is 10000 or more, and the molar extinction coefficient at the hologram reproduction wavelength is 100 or less. (1) The hologram recording material according to (1).
(3) The hologram recording material (4) according to (1) or (2), further comprising at least a sensitizing dye, a polymerization initiator, and a binder in addition to the dye having the polymerizable group. The hologram recording material according to (3), comprising at least one polymerizable compound having no portion.
(5) The hologram recording material according to (4), wherein at least one of the polymerizable compounds having no dye portion is a liquid having a boiling point of 100 ° C. or higher.
(6) The hologram recording material according to any one of (3) to (5), wherein the refractive index at the hologram reproduction wavelength is larger for the dye having a polymerizable group than for the binder.
(7) The hologram recording material according to any one of (4) to (6), wherein the refractive index at the hologram reproduction wavelength is higher for a polymerizable compound having no dye portion than for a binder.
(8) The polymerizable compound having no dye portion contains at least one aryl group, aromatic heterocyclic group, chlorine atom, bromine atom, iodine atom, or sulfur atom, and the binder does not contain them. The hologram recording material according to any one of (4) to (7), which is characterized.
(9) Using the hologram recording material according to (4), the excited state of the sensitizing dye generated by absorbing light by irradiation with hologram recording light activates the polymerization initiator by electron transfer or energy transfer, and polymerizes. Polymerization of a dye having a polymerizable group and a polymerizable compound not having a dye part occurs, and at that time, the dye having a polymerizable group and the polymerizable compound not having a dye part are mainly moved in a bright interference part. A hologram recording method, wherein interference fringes are recorded by refractive index modulation due to binder being mainly driven into an interference dark part where light is weaker.
(10) The hologram recording method according to (9), wherein the polymerization reaction is any one of radical polymerization, cationic polymerization, and anionic polymerization in (9).
(11) When the polymerizable group of the polymerizable compound having the polymerizable group or the polymerizable compound not having the dye portion is radical polymerization, an acryloyl group, a methacryloyl group, a styryl group, vinyl is used as the polymerizable group. It has an ethylenically unsaturated group moiety such as a group, and when polymerization is cationic polymerization or anionic polymerization, it has any of an oxirane ring, oxetane ring, vinyl ether group, and N-vinylcarbazole moiety as a polymerizable group The hologram recording material according to (1) to (8).
(12) The polymerization initiator is 1) a ketone polymerization initiator, 2) an organic peroxide polymerization initiator, 3) a bisimidazole polymerization initiator, 4) a trihalomethyl-substituted triazine polymerization initiator, and 5) a diazonium. Salt-based polymerization initiator, 6) diaryl iodonium salt-based polymerization initiator, 7) sulfonium salt-based polymerization initiator, 8) triphenylalkyl borate-based polymerization initiator, 9) diaryl iodonium organic boron complex-based polymerization initiator, 10) sulfonium organic boron complex polymerization initiator, 11) cationic dye organic boron complex polymerization initiator, 12) anionic dye onium salt complex polymerization initiator, 13) metal arene complex polymerization initiator, 14) sulfone The hologram recording material according to any one of (3) to (8) and (11), wherein the hologram recording material is any one of an acid ester polymerization initiator.
(13) In (12), the polymerization initiator is a radical polymerization initiator that generates radicals, 1) a ketone polymerization initiator, 2) an organic peroxide polymerization initiator, and 3) a bisimidazole polymerization start. 4) Trihalomethyl-substituted triazine polymerization initiator, 5) Diazonium salt polymerization initiator, 6) Diaryliodonium salt polymerization initiator, 7) Sulfonium salt polymerization initiator, 8) Triphenylalkylborate salt Polymerization initiator, 9) Diaryliodonium organic boron complex polymerization initiator, 10) Sulfonium organic boron complex polymerization initiator, 11) Cationic dye organic boron complex polymerization initiator, 12) Anionic dye onium salt complex polymerization The hologram recording material according to (12), which is any one of an initiator and 13) a metal arene complex polymerization initiator.
(14) In (12), the polymerization initiator is a cationic polymerization initiator that generates an acid, 4) a trihalomethyl-substituted triazine polymerization initiator, 5) a diazonium salt polymerization initiator, 6) a diaryl iodonium salt system The hologram recording material according to (12), which is any one of a polymerization initiator, 7) a sulfonium salt polymerization initiator, 13) a metal arene complex polymerization initiator, and 14) a sulfonate ester polymerization initiator .
(15) The hologram recording material as described in (10), which contains a photobase generator when the polymerization reaction is anionic polymerization in (10).
(16) The hologram recording material according to any one of (3) to (8) and (11) to (15), wherein the molar absorption coefficient of the sensitizing dye at a hologram recording wavelength is 1 or more and 2000 or less.
(17) The hologram recording material has a film thickness of 100 μm or more, and a sensitizing dye is added so that the transmittance of light having a hologram recording wavelength is 10% or more and 99% or less (3 ) To (8) and (11) to (16).
(18) The hologram recording method according to (9) or (10), wherein the hologram recording wavelength and the reproduction wavelength are the same.
(19) The hologram recording method according to (18), wherein the hologram recording / reproducing wavelength is 532 nm in (18).
(20) The hologram recording method according to (18), wherein the hologram recording / reproducing wavelength is in a range of 405 to 415 nm in (18).
(21) A volume phase hologram recording method comprising performing volume phase hologram recording using the hologram recording method according to (9), (10), (18) to (20).
(22) The hologram recording material according to any one of (1) to (8) and (11) to (17), wherein the hologram recording is a system that cannot be rewritten.
(23) A hologram recording method comprising performing multiple hologram recording 10 times or more using the hologram recording material according to (1) to (8), (11) to (17), and (22).
(24) The exposure described in (9), (10), (18) to (21), (23) is characterized in that the exposure amount at the time of multiplex recording can be kept constant throughout the multiplex recording. Hologram recording method and hologram recording material capable of such recording.
(25) The hologram recording method described in (9), (10), (18) to (21), (23), (24) and such a process are characterized in that a wet process is not performed after hologram exposure. Hologram recording material that is possible.
(26) The hologram recording material according to (1) to (8), (11) to (17), (22), (24), and (25) is made of ultraviolet light other than recording light and reproduction light, visible light, The hologram recording material according to any one of (1) to (25), wherein a light shielding filter capable of cutting a part of the wavelength region of infrared light is provided on the front surface, the back surface, or both surfaces of the hologram recording material.
(27) An optical recording medium using the hologram recording material according to (1) to (8), (11) to (17), (22), or (24) to (26).
(28) The recording / reproducing method for the optical recording medium according to (27), wherein a hologram recording / reproducing method is used.
(29) The hologram recording material described in (1) to (8), (11) to (17), (22), (24) to (27) is stored in a light-shielding cartridge at the time of storage. Optical recording media.
(30) (1) to (8), (11) to (17), (22), a three-dimensional display hologram using the hologram recording material described in (24) to (26), and (9), (10), A method for producing a three-dimensional display hologram using the hologram recording method according to any one of (18) to (21) and (23) to (25).
(31) A holographic optical element using the hologram recording material according to (1) to (8), (11) to (17), (22), (24) to (26), and (9), (10), A method for producing a holographic optical element using the hologram recording method according to any one of (18) to (21) and (23) to (25).

  According to the present invention, a hologram recording material that can be applied to a high-density optical recording medium, a three-dimensional display, a holographic optical element, etc., and can achieve both high sensitivity and high diffraction efficiency, good storage stability, low shrinkage, and dry processing. And a hologram recording method is obtained.

  The hologram recording method and hologram recording material of the present invention will be described in detail below.

The hologram recording material of the present invention is preferably not subjected to wet processing.
The hologram recording material of the present invention is preferably a system that cannot be rewritten. 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 light used for hologram recording of the present invention is preferably any of ultraviolet light, visible light, and infrared light having a wavelength of 200 to 2000 nm, more preferably ultraviolet light or visible light having a wavelength of 300 to 700 nm, and still more preferably. It is visible light of 400 to 700 nm.
Furthermore, the actinic radiation of the present invention is preferably a coherent laser beam (having the same phase and wavelength). The laser used may be any of a solid laser, a semiconductor laser, a gas laser, and a liquid laser. Preferred laser beams include, for example, a 532 nm YAG laser double wave, a 355 nm YAG laser triple wave, and a wavelength around 405 to 415 nm. GaN laser, 488 or 515 nm Ar ion laser, 632 or 633 nm He—Ne laser, 647 nm Kr ion laser, 694 nm ruby laser, 636, 634, 538, 534, 442 nm He—Cd laser, etc. .
It is also preferable to use a nanosecond or picosecond order pulse laser.
When the hologram recording material of the present invention is used for an optical recording medium, it is preferable to use a 532 nm YAG laser double wave or a GaN laser near 405 to 415 nm.
The wavelength of light used for hologram reproduction is preferably the same or longer than the wavelength of light used for hologram exposure (recording), and more preferably the same.

In the hologram recording material of the present invention, after the hologram exposure, a fixing step may be performed by light, heat, or both.
In particular, when an acid proliferating agent or a base proliferating agent is used in the hologram recording material of the present invention, it is preferable to use heating for fixing in order to make the acid proliferating agent or the base proliferating agent function effectively.
In the case of light fixing, the entire area of the hologram recording material is irradiated with ultraviolet light or visible light (non-interference exposure). Preferably, the light source used includes 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, an organic EL, and the like.
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.

  The refractive index modulation amount at the time of interference fringe recording is preferably 0.00001 to 0.5, and more preferably 0.0001 to 0.3. In addition, it is preferable that the refractive index modulation amount is smaller as the film thickness of the hologram recording material is larger, and it is preferable that the refractive index modulation amount is larger as the film thickness of the hologram recording material is thinner.

The (relative) diffraction efficiency η of the hologram recording material is given by the following equation.
η = Idiff / Io (Formula 1)
Here, Io is the intensity of transmitted light that is not diffracted, and Idiff is the intensity of light that is diffracted (transmitted) or reflected (reflected). The diffraction efficiency takes any value from 0 to 100%, preferably 30% or more, more preferably 60% or more, and most preferably 80% or more.

The sensitivity of the hologram recording material is generally expressed by the exposure amount per unit area (mJ / cm ² ), and it can be said that the smaller the value, the higher the sensitivity. However, the exposure amount at which time is taken as sensitivity varies depending on documents and patents. When the exposure amount starts recording (refractive index modulation), the exposure amount gives the maximum diffraction efficiency (refractive index modulation). In some cases, the exposure amount giving a diffraction efficiency that is half of the maximum diffraction efficiency may be the exposure amount at which the gradient of the diffraction efficiency is maximum with respect to the exposure amount E.
Further, from the Kugelnick's theoretical formula, the refractive index modulation amount Δn for giving a certain diffraction efficiency is inversely proportional to the film thickness d. That is, the sensitivity for giving a certain diffraction efficiency varies depending on the film thickness, and the smaller the refractive index modulation amount Δn is, the thicker the film thickness d is. Therefore, unless conditions such as film thickness are matched, the sensitivity cannot be generally compared.
In the present invention, sensitivity is defined as “exposure amount giving half the maximum diffraction efficiency (mJ / cm ² )”. The sensitivity of the hologram recording material of the present invention is preferably 1 J / cm ² or less, more preferably 500 mJ / cm ² or less, and 200 mJ / cm ² or less, for example, when the film thickness is about 10 to 200 μm. More preferably, it is most preferably 100 mJ / cm ² or less.

  When the hologram recording material of the present invention is used as an optical recording medium in a holographic memory, a large amount of two-dimensional digital information (referred to as signal light) is recorded using a spatial light modulation element (SLM) such as DMD or LCD. Is preferred. In order to increase the recording density, it is preferable to use multiplex recording. The multiplex recording method includes multiplex recording such as angle multiplex, phase multiplex, wavelength multiplex, and shift multiplex. It is preferable to use shift multiple recording. Also, CCD and CMOS are preferably used for reading the reproduced two-dimensional data.

  When the hologram recording material of the present invention is used in a holographic memory as an optical recording medium, it is essential to perform multiplex recording in order to improve the capacity (recording density). At that time, it is more preferable to perform multiplex recording 10 times or more, more preferably to perform multiplex recording 50 times or more, and most preferably to perform multiplex recording 100 times or more. Furthermore, it is more preferable from the viewpoints of simplifying the recording system, improving the S / N ratio, etc. that the exposure amount in the multiple recording can be kept constant throughout the multiple recording.

  When the hologram recording material of the present invention is used for an optical recording medium, it is preferable that the hologram recording material during storage is stored in a light shielding cartridge. In addition, a light shielding filter capable of cutting a part of the wavelength range of ultraviolet light, visible light, and infrared light other than the recording light and reproduction light wavelengths may be provided on the front surface, back surface, or both surfaces of the hologram recording material. preferable.

  When the hologram recording material of the present invention is used for an optical recording medium, the optical recording medium may be disk-shaped, card-shaped, tape-shaped, or any shape.

  Hereinafter, each hologram recording method of the present invention and each component of the hologram recording material capable of such a recording method will be described in detail.

  The hologram recording material of the present invention includes at least one dye having a polymerizable group. Here, the “dye” in the present invention refers to a compound that absorbs any of ultraviolet light, visible light, and infrared light having a wavelength of 300 to 2000 nm, and more preferably ultraviolet light having a wavelength of 330 to 700 nm or visible light. It refers to a compound that absorbs light, and more preferably refers to a compound that absorbs visible light of 400 to 700 nm. In that case, the molar extinction coefficient in the region is preferably 5000 or more, more preferably 10000 or more, and most preferably 20000 or more.

  The hologram recording material of the present invention preferably has at least a sensitizing dye, a polymerization initiator, and a binder in addition to the dye having a polymerizable group, and further has a polymerizable compound having no dye portion. preferable. Here, it is more preferable that at least one of the polymerizable compounds having no dye portion is a liquid having a boiling point of 100 ° C. or higher.

  In the hologram recording method of the present invention, a sensitizing dye excited state generated by absorbing light by holographic recording light irradiation activates a polymerization initiator by electron transfer or energy transfer, and a dye and a dye part having a polymerizable group Polymerization of a polymerizable compound that does not have light, and in that case, the dye having a polymerizable group and the polymerizable compound that does not have a dye part move mainly in the bright interference part where the light is stronger, and the interference dark part where the light is weaker Further, it is characterized in that interference fringes are recorded by refractive index modulation caused mainly by the binder being driven away.

At that time, it is important that the refractive index is different between the interference bright part and the interference dark part. In the hologram recording material of the present invention, it is preferable that the refractive index is large in the bright interference part.
Therefore, it is preferable that the refractive index at the hologram reproduction wavelength of the present invention is larger for the dye having a polymerizable group than for the binder.
In general, the refractive index of a dye takes a high value in the region where the wavelength is longer than that near the absorption maximum wavelength (λmax), and particularly takes a very high value in a region where the wavelength is about 200 nm longer than λmax to λmax. It takes a high value exceeding 2 and even exceeding 2.5.
On the other hand, an organic compound that is not a pigment such as a binder polymer usually has a refractive index of about 1.4 to 1.6.
Therefore, the hologram recording material of the present invention is advantageous in terms of high sensitivity because a dye having a large refractive index is used for refractive index modulation. In order to increase the sensitivity, the dye having a polymerizable group preferably has a λmax that is 10 to 200 nm shorter than the hologram reproduction wavelength in the absorption spectrum, more preferably 30 to 130 nm. It has a certain λmax and ε is 10,000 or more, more preferably 20000 or more.
Furthermore, for high diffraction efficiency, the molar extinction coefficient at the hologram reproduction wavelength is preferably 100 or less, more preferably 10 or less, and most preferably 0.

Furthermore, in the hologram recording material of the present invention, also when a polymerizable compound having no dye portion is used, the refractive index at the hologram reproduction wavelength is preferably larger for the polymerizable compound having no dye portion than the binder. .
At that time, the polymerizable compound having no dye portion contains at least one aryl group, aromatic heterocyclic group, chlorine atom, bromine atom, iodine atom, sulfur atom, and the binder may not contain them. More preferred.

  The polymerization reaction in the present invention is preferably radical polymerization, cationic polymerization or anionic polymerization, and is preferably radical polymerization or cationic polymerization.

  At that time, when the polymerizable group of the polymerizable compound having a polymerizable group or a polymerizable compound having no dye portion is radical polymerization, the polymerizable group may be acryloyl group, methacryloyl group, styryl group, vinyl group, etc. It has an ethylenically unsaturated group portion, preferably an acryloyl group or a methacryloyl group, and when the polymerization is cationic polymerization or anionic polymerization, the polymerizable group is an oxirane ring, oxetane ring, vinyl ether group, N-vinylcarbazole moiety. It is preferable to have any one, preferably an oxirane ring or an oxetane ring.

Next, the pigment | dye which has a polymeric group of this invention is demonstrated in detail.
Among the dyes having a polymerizable group of the present invention, the dye part is preferably a cyanine dye, squarylium cyanine dye, styryl dye, pyrylium dye, merocyanine dye, arylidene dye, oxonol dye, azurenium dye, coumarin dye, ketocoumarin dye. , Styrylcoumarin dye, pyran dye, xanthene dye, thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, phthalocyanine dye, azaporphyrin dye, porphyrin dye, condensed aromatic dye, perylene dye, azomethine dye, anthraquinone dye , Metal complex dyes, azo dyes and the like, more preferably cyanine dyes, squarylium cyanine dyes, styryl dyes, merocyanine dyes, arylidene dyes, oxonol dyes, coumarin colors , Xanthene dyes, phenothiazine dyes, condensed aromatic dyes, include azo dyes, still more preferably, cyanine dyes, merocyanine dyes, arylidene dyes, oxonol dyes, coumarine dyes, xanthene dyes, and azo dyes.

  In addition, "Dye Handbook" (Shin Okawara et al., Kodansha 1986), "Chemistry of Functional Dye" (Shin Okawara et al. CMC 1981), "Special Functional Materials" (Chemical Icmori Taro Saburo et al. CMC 1986) The dyes and dyes described in 1 can also be used as the dye part of the present invention.

  Regarding the dye having a polymerizable group of the present invention, the polymerizable group is as described above. As the polymerizable group, any part of the dye may be substituted.

  Although the specific example of the pigment | dye which has the polymeric group of this invention is shown below, this invention is not limited to this.

  First, the sensitizing dye that absorbs light by hologram exposure and generates an excited state in the hologram recording material of the present invention will be described in detail.

  The sensitizing dye of the present invention preferably generates an excited state by absorbing any of ultraviolet light, visible light, and infrared light having a wavelength of 200 to 2000 nm, more preferably ultraviolet light having a wavelength of 300 to 700 nm. It absorbs light or visible light to generate an excited state, and more preferably absorbs visible light of 400 to 700 nm to generate an excited state.

The sensitizing dye of the present invention is preferably a cyanine dye, squarylium cyanine dye, styryl dye, pyrylium dye, merocyanine dye, arylidene dye, oxonol dye, azurenium dye, coumarin dye, ketocoumarin dye, styrylcoumarin dye, pyran dye, xanthene dye. Thioxanthene dye, phenothiazine dye, phenoxazine dye, phenazine dye, phthalocyanine dye, azaporphyrin dye, porphyrin dye, condensed aromatic dye, perylene dye, azomethine dye, anthraquinone dye, metal complex dye, metallocene dye, etc. And more preferably cyanine dyes, squarylium cyanine dyes, pyrylium dyes, merocyanine dyes, oxonol dyes, coumarin dyes, ketocoumarin dyes, styryl coumarin dyes. Pyran dyes, xanthene dyes, thioxanthene dyes, condensed aromatic dyes, metal complex dyes, include metallocene dyes, more preferred are cyanine dyes, merocyanine dyes, oxonol dyes, metal complex dyes, metallocene dyes. The metal complex dye is particularly preferably a Ru complex dye, and the metallocene dye is particularly preferably a ferrocene.
In addition, "Dye Handbook" (Shin Okawara et al., Kodansha 1986), "Chemistry of Functional Dye" (Shin Okawara et al. CMC 1981), "Special Functional Materials" (Chemical Icmori Taro Saburo et al. CMC 1986) The dyes and dyes described in 1) can also be used as the sensitizing dye of the present invention. The sensitizing dye of the present invention is not limited to these, and any dye and dye that absorbs visible light can be used. These sensitizers can be selected in accordance with the wavelength of the radiation used as a light source according to the purpose of use, and two or more sensitizing dyes may be used in combination depending on the application.

Here, the hologram recording material of the present invention is preferably used for an optical recording medium, that is, a holographic memory. In the holographic memory, in order to increase the recording density, multiple recording is performed over 50 times, and preferably over 100 times. At that time, the film thickness of the hologram recording material is generally required to be at least 100 μm or more, more preferably 500 μm or more in order to generate severe angle dependency due to severe black conditions. Therefore, it is preferable that the hologram recording light passes through the hologram recording material, preferably 10% to 99%, more preferably 20% to 90%.
Therefore, when a sensitizing dye having a high molar extinction coefficient is used, it is necessary to considerably reduce the amount of the sensitizing dye in order for the recording light to pass through such a thick hologram recording material. This is a problem because it causes a significant decrease. Therefore, as a sensitizing dye for holographic memory, ε is as low as possible, and it is preferable that the amount is increased in view of sensitivity and multiplex recording characteristics.
The molar extinction coefficient of the sensitizing dye at the hologram exposure wavelength is preferably from 1 to 10,000, more preferably from 1 to 5000, further preferably from 5 to 2000, and more preferably from 10 to 1000. Most preferred.

  Specific examples of the sensitizing dye of the present invention are given below, but the present invention is not limited thereto.

  Other preferred examples of the sensitizing dye of the present invention are described in Japanese Patent Application No. 2003-300059. The sensitizing dye of the present invention is a commercial product, or can be synthesized by a known method.

Next, the polymerization initiator in the hologram recording material of the present invention will be described in detail.
The polymerization initiator of the present invention is a radical or acid (Bronsted acid or Lewis acid) or base (Bronsted acid) by performing energy transfer or electron transfer (giving or receiving electrons) from the excited state of the sensitizing dye. Base or Lewis base) and a compound capable of 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 14 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) Sulphonium organoboron complex polymerization initiator
11) Cationic sensitizing dye organoboron complex polymerization initiator
12) Anionic sensitizing dye onium salt complex polymerization initiator
13) Metal arene complex polymerization initiator
14) Sulfonic acid ester polymerization initiator

The preferred system described above will be specifically described below. 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. Moreover, the substituent which can be used for the compound in the present invention may be any substituent regardless of the presence or absence of substitution.
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.

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 (eg, 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-tetrahydronaphthacene Non, as well as 1,2,3,4-tetrahydrobenz (a) anthracene-7,12-dione).

  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

  Preferred among bisimidazole 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).

  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 acid generator

  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, such as vinyl, allyl, 2-butenyl, 1,3-butadienyl), cycloalkyl group (preferably C 3-20, 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). For example, pyridyl, thienyl, furyl, thiazolyl, imidazolyl, pyrazolyl, pyrrolidino Piperidino, morpholino), alkynyl groups (preferably having 2 to 20 carbon atoms, such as ethynyl, 2-propynyl, 1,3-butadiynyl, 2-phenylethynyl), halogen atoms (for example, 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, acyl group (Preferably C 1-20, such as acetyl, benzoyl, salicyloyl, pivaloyl), alkoxy group (preferably C 1-20, such as methoxy, butoxy, cyclohexyloxy), aryloxy group (preferably C 6 -26, for example, phenoxy, 1-naphthoxy), alkylthio group ( Preferably C number 1-20, for example, methylthio, ethylthio), arylthio group (preferably C number 6-20, such as 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-methylsulfamoyl) N-phenylsulfamoyl), a carbamoyl group (preferably having a C number of 1 to 20, for example, carbamoyl, N-methylcarbamoyl, N, N-dimethylcarbamoyl, N-phenylcarbamoyl), an acylamino group (preferably having a C number of 1). -20, for example acetylamino, Nzoylamino), imino group (preferably C 2-20, eg phthalimino), acyloxy group (preferably C 1-20, eg acetyloxy, benzoyloxy), alkoxycarbonyl group (preferably C 2-20, eg , Methoxycarbonyl, phenoxycarbonyl), carbamoylamino group (preferably having 1 to 20 carbon atoms, such as carbamoylamino, N-methylcarbamoylamino, N-phenylcarbamoylamino), more preferably alkyl group, 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 preferably represents —CR ₂₁ R ₂₂ R ₂₃ , more preferably —CCl ₃ group, and R ₂₅ is preferably —CR ₂₁ R ₂₂ R ₂₃ , an alkyl group, an alkenyl group, and an aryl group.

  Specific examples of the trihalomethyl-substituted triazine acid generator 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, etc. . Preferable examples also include compounds described in British Patent No. 1388492 and JP-A No. 53-133428.

5) Diazonium salt acid generator

  The diazonium salt acid generator 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, 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 acid generators such as benzene diazonium, 4-methoxy diazonium, 4-methyl aforementioned X ₂₁ of diazonium ^- such salts.

6) Diaryliodonium salt acid generator

  The diaryliodonium salt acid generator 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 represent 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 represents an integer of 0 to 5, preferably an integer of 0 to 1. When a22 and a23 are 2 or more, the 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-based acid generator include diphenyliodonium, 4,4′-dichlorodiphenyliodonium, 4,4′-dimethoxydiphenyliodonium, 4,4′-dimethyldiphenyliodonium, 4,4′-di- chlorides such as t-butyldiphenyliodonium, 3,3′-dinitrodiphenyliodonium, phenyl (p-methoxyphenyl) iodonium, phenyl (p-octyloxyphenyl) iodonium, bis (p-cyanophenyl) iodonium, bromide, iodide, Tetrafluoroborate, hexafluorophosphate, hexafluoroarsenate, hexafluoroantimonate, perchlorate, trifluoromethanesulfonate, 9,10-dimethoxyanthracene-2-sulfonate, methanes Examples thereof include sulfonate, benzenesulfonate, 4-trifluoromethylbenzenesulfonate, tosylate, and tetra (pentafluorophenyl) borate.
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 acid generator

  The sulfonium salt acid generator 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 , and R ₃₂ each independently represents an alkyl group, an aryl group, or a heterocyclic group (preferred examples are the same as those for R ₂₄ ), preferably an alkyl group, a phenacyl group, or an aryl group.

  Specific examples of the sulfonium salt acid generator 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-sulfonate , Methanesulfonate, benzenesulfonate, 4-trifluoromethylbenzenesulfonate, tosylate, tetra (pentafluorophenyl) borate and the like.

8) Borate polymerization initiator

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

In 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, R ₃₃ , R ₃₄ , R ₃₅ and R ₃₆ are not all aryl groups 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-based 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 the general formula (17), R ₃₃ , R ₃₄ , R ₃₅ and R ₃₆ have the same _{meaning as} in the general formula (15). R ₃₇ , R ₃₈ and R ₃₉ are each independently an alkyl group, aryl group, alkenyl group, alkynyl group, cycloalkyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group or amino group (more preferred examples) Are 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-based 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) Cationic sensitizing dye organoboron complex polymerization initiator

When the polymerization initiator of the present invention is a cationic sensitizing dye organic boron complex polymerization initiator, the cationic sensitizing dye may serve as the sensitizing dye of the present invention.
The cationic sensitizing dye organoboron complex polymerization initiator is preferably represented by the general formula (18).

In the general formula (18), (Dye-1) ⁺ is a cationic sensitizing dye, and a preferable example is a cationic sensitizing dye among the sensitizing dyes described above. For example, a cyanine dye and a merocyanine dye are preferable, and a cyanine dye is more preferable. R ₃₃ , R ₃₄ , R ₃₅ , and R ₃₆ have the same _{meaning as} in general formula (15).

  Specific examples of the cationic sensitizing dye organic boron complex polymerization initiator include the following I-11, I-12, I-13, I-14, and the like.

  Specific examples include cationic dye-borate anion complexes described in JP-A-62-143044 and 62-150242.

  12) Anionic sensitizing dye onium salt complex polymerization initiator

When the polymerization initiator of the present invention is an anionic sensitizing dye onium salt complex polymerization initiator, the anionic sensitizing dye may serve as the sensitizing dye of the present invention.
The anionic sensitizing dye onium salt-based polymerization initiator is preferably represented by the general formula (19).

In the general formula (19), (Dye-2) ⁻ is an anionic sensitizing dye, and a preferable example is an anionic sensitizing dye in the sensitizing dye described above. For example, a cyanine dye, a merocyanine dye, and an oxonol dye are preferable, and a cyanine dye and an oxonol dye are more preferable. X ₂₃ ⁺ represents a cation moiety of the diazonium salt of the general formula (12), a cation moiety of the diaryliodonium salt of the general formula (13), and a cation moiety of the sulfonium salt of the general formula (14) (all preferred examples are described above). A cation moiety of the diaryliodonium salt of the general formula (13) or a cation moiety of the sulfonium salt of the general formula (14).

  Specific examples of the anionic sensitizing dye onium salt-based polymerization initiator include I-15 to I-32 shown below.

  13) 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.)”, Vol. 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), titanones described in JP-A No. 61-151197, and the like.

14) 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.

15) 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), 1- benzyl-2-cyano-pyridinium salt pyridinium salts such as hexafluoroantimonate, phenyl iso oxazolone, silanol-aluminum complex, such as aluminate complexes described in JP-a-3-209477 and the like.

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 that can activate radical polymerization generates radicals by performing energy transfer or electron transfer (giving electrons to or receiving electrons from the sensitizing dye) from the excited state of the sensitizing dye. And a polymerization initiator capable of initiating 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) Sulphonium organoboron complex polymerization initiator
11) Cationic sensitizing dye organoboron complex polymerization initiator
12) Anionic sensitizing dye onium salt complex polymerization initiator
13) Metal arene complex polymerization initiator

More preferably as a polymerization initiator capable of activating radical polymerization,
1) Ketone-based polymerization initiator 3) Bisimidazole-based polymerization initiator 4) Trihalomethyl-substituted triazine-based polymerization initiator 6) Diaryliodonium salt-based polymerization initiator 7) Sulfonium salt-based polymerization initiator
11) Cationic sensitizing dye organoboron complex polymerization initiator
12) Anionic sensitizing dye onium salt complex polymerization initiators are mentioned, more preferably
3) Bisimidazole polymerization initiator 6) Diaryliodonium salt polymerization initiator 7) Sulfonium salt polymerization initiator
11) Cationic sensitizing dye organoboron complex polymerization initiator
12) Anionic sensitizing dye onium salt complex polymerization initiators.

  A polymerization initiator that can only activate cationic polymerization means that an acid (Bronsted acid or Lewis acid) is generated without generating a radical by performing energy transfer or electron transfer from the excited state of the sensitizing dye, and polymerization is performed with the acid. It is a polymerization initiator capable of initiating cationic polymerization of a functional compound.

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

  Examples of the cationic polymerization initiator include “UV curing; science and technology (UVCURING; SCIENCE AND TECHNOLOGY)” [p. 23-76, S.M. Edited by S. PETER PAPPAS, A TECHNOLOGY MARKING PUBLICATION] and “Comments Inorg. Chem.” [B. Klingelt, M.M. Reedy Car and A. Rolov (B. KLINGERT, M. RIEDICER and A. ROLOFF), Volume 7, No. 3, p109-138 (1988)] and the like can also be used.

  A polymerization initiator capable of simultaneously activating radical polymerization and cationic polymerization is generated by simultaneously generating radicals or acids (Bronsted acid or Lewis acid) by performing energy transfer or electron transfer from the excited state of the sensitizing dye. It is a polymerization initiator capable of initiating radical polymerization of a polymerizable compound by radicals and cationic polymerization of the polymerizable compound by generated acid.

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.

  When using cationic polymerization, it is also preferable to use an acid proliferating agent from the viewpoint of increasing sensitivity. Specific examples of preferred acid proliferating agents include those described in Japanese Patent Application No. 2003-182849.

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 a sensitizing dye or colored body excited state. 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 a sensitizing dye or a colored body excited state.
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.

  It is also preferable to use a base proliferating agent from the viewpoint of increasing sensitivity. Specific examples of preferred base generators and base proliferators as anionic polymerization initiators include the examples described in Japanese Patent Application No. 2003-178083.

  Specific examples of preferred polymerization initiators in the present invention are listed below, but the present invention is not limited thereto.

  Next, the polymerizable compound having no dye portion in the hologram recording material of the present invention will be described.

  In the hologram recording material of the present invention, the refractive index of the polymerizable compound having no dye portion and the binder is preferably different, and the polymerizable compound having no dye portion is preferably higher than that of the binder. As a result, the photopolymerization caused by hologram exposure causes non-uniformity in the composition ratio of the polymerizable compound and its polymerization reaction product to the binder in the interference bright part (amplification part) and interference dark part (non-amplification part). Interference fringe recording by rate modulation becomes possible.

In order to increase the refractive index modulation, it is preferable that the refractive index difference in the bulk of the polymerizable compound having no dye portion and the binder is large, and the refractive index difference is preferably 0.01 or more, and 0.05 or more. Is more preferably 0.1 or more.
For this purpose, the polymerizable compound having no dye portion contains at least one aryl group, aromatic heterocyclic group, chlorine atom, bromine atom, iodine atom, or sulfur atom, and the binder does not contain them. Garage.
In order to increase the refractive index modulation, it is preferable that the polymerizable compound easily moves in the hologram recording material.

The polymerizable compound of the present invention is a radical, acid (Bronsted acid or Lewis acid), base (Bronsted base or Lewis base) generated by irradiating light to a sensitizing dye (or color former) and a polymerization initiator. ) Is a compound capable of undergoing addition polymerization to be oligomerized or polymerized.
The polymerizable compound of the present invention may be monofunctional or polyfunctional, may be a single component or a multicomponent, and may be a monomer, a prepolymer (eg, a dimer or oligomer), or a mixture thereof, but is a monomer. It is preferable.
The form may be liquid or solid at room temperature, but it is preferably a liquid having a boiling point of 100 ° C. or higher, or a mixture of a liquid monomer having a boiling point of 100 ° C. or higher and a solid monomer. .

The polymerizable compound having no dye moiety of the present invention is roughly classified into a polymerizable compound capable of radical polymerization and a polymerizable compound capable of cationic or anionic polymerization.
Below, a preferable example is demonstrated for every polymerizable compound in which radical polymerization is possible, and every polymerizable compound in which cation or anion polymerization is possible.

  The radical polymerizable compound preferably has a high refractive index, and the high refractive index radical polymerizable compound of the present invention has at least one ethylenically unsaturated double bond in the molecule, and further has at least one or more A compound containing an aryl group, an aromatic heterocyclic group, a chlorine atom, a bromine atom, an iodine atom or a sulfur atom is preferred, and a liquid having a boiling point of 100 ° C. or higher is preferred.

  Specific examples thereof include the following polymerizable monomers and prepolymers (dimers, oligomers, etc.) comprising them.

  As the high refractive index radical polymerizable monomer, styrene, 2-chlorostyrene, 2-bromostyrene, methoxystyrene, phenyl acrylate, p-chlorophenyl acrylate, 2-phenylethyl acrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenol ethoxylate acrylate, 2- (p-chlorophenoxy) ethyl acrylate, benzyl acrylate, 2- (1-naphthyloxy) ethyl acrylate, 2,2-di (p-hydroxyphenyl) Propane diacrylate or dimethacrylate, 2,2-di (p-hydroxyphenyl) propane dimethacrylate, polyoxyethyl-2,2-di (p-hydroxyphenyl) propane dimethacrylate, di (2-methacryloxy) of bisphenol-A Ethyl) ether, ethoxylated bisphenol-A diacrylate, bisphenol-A di (3-acryloxy-2-hydroxypropyl) ether, bisphenol-A di (2-acryloxyethyl) ether, tetrachloro-bisphenol-A Di (3-acryloxy-2-hydroxypropyl) ether, di (2-methacryloxyethyl) ether of tetrachloro-bisphenol-A, di (3-methacryloxy-2-hydroxypropyl) ether of tetrabromo-bisphenol-A, tetrabromo -Di (2-methacryloxyethyl) ether of bisphenol-A, di (3-methacryloxy-2-hydroxypropyl) ether of diphenolic acid, 1,4-benzenediol dimethacrylate, 1,4-diisopropenyl vinyl And 1,3,5-triisopropenylbenzene, benzoquinone monomethacrylate, 2- [β- (N-carbazyl) propionyloxy] ethyl acrylate, phenylthioacrylate, 4-iodophenylacrylate, and the like. Preferably 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, phenol ethoxylate acrylate, 2- (p-chlorophenoxy) ethyl acrylate, p-chlorophenyl acrylate, phenyl acrylate, 2-phenyl acrylate Examples include ethyl, di (2-acryloxyethyl) ether of bisphenol-A, ethoxylated bisphenol-A diacrylate, and 2- (1-naphthyloxy) ethyl acrylate.

  The polymerizable compounds useful in the present invention are liquids, but they are N-vinylcarbazole, H.I. Journal of Polymer Science: Polymer Chemistry Edition, Vol. 18, pages 9-18 (1979) by Kamogawa et al., Ethylenically unsaturated carbazole monomers, 2-naphthyl acrylate, pentachlorophenyl acrylate, acrylic acid 2, It may be used in admixture with a second solid polymerizable compound such as 4,6-tribromophenyl, bisphenol-A diacrylate, 2- (2-naphthyloxy) ethyl acrylate, and N-phenylmaleimide.

  The cationic polymerizable compound of the present invention is a compound that is polymerized by an acid generated by a sensitizing dye or color former and a cationic polymerization initiator, and the anionic polymerizable compound of the present invention is an anionic polymerization with a sensitizing dye or color former. A compound in which polymerization is initiated by a base generated by an initiator, such as “Chemtech. Oct.” [J. V. JV Crivello, page 624, (1980)], Japanese Patent Application Laid-Open No. 62-149784, Journal of the Adhesion Society of Japan [Vol. 26, No. 5, pp. 179-187 (1990)] and the like.

The cationically polymerizable compound of the present invention is preferably a compound having at least one oxirane ring, oxetane ring, vinyl ether group or N-vinylcarbazole moiety in the molecule, more preferably a compound having an oxirane ring moiety.
The anionic polymerizable compound of the present invention is preferably an oxirane ring, an oxetane ring, a vinyl ether group, an N-vinylcarbazole moiety, an ethylenic double bond moiety having an electron-withdrawing substituent, a lactone moiety, a lactam moiety, or a cyclic urethane moiety. , A compound having at least one cyclic urea moiety or cyclic siloxane moiety in the molecule, and more preferably a compound having an oxirane ring moiety.

  The cation or anion polymerizable compound preferably has a high refractive index, and is preferably a compound containing at least one aryl group, aromatic heterocyclic group, chlorine atom, bromine atom, iodine atom or sulfur atom, and at least one or more. It is preferable that the aryl group is included. Moreover, it is preferable that it is a liquid whose boiling point is 100 degreeC or more.

  Specific examples thereof include the following polymerizable monomers and prepolymers (dimers, oligomers, etc.) comprising them.

  Preferred as a high refractive index cation or anion polymerizable monomer having an oxirane ring is phenyl glycidyl ether, p-t-butylphenyl glycidyl ether, diglycidyl phthalate, resorcin diglycidyl ether, dibromophenyl glycidyl ether, dibromoneopentyl glycol Diglycidyl ether, 4,4′-bis (2,3-epoxypropoxyperfluoroisopropyl) diphenyl ether, p-bromostyrene oxide, bisphenol-A-diglycidyl ether, tetrabromobisphenol-A-diglycidyl ether, bisphenol-F -Diglycidyl ether etc. are mentioned. 1,3-bis (3 ', 4'-epoxycyclohexyl) ethyl) -1,3, -diphenyl-1,3, -dimethyldisiloxane and the like.

  In addition, the following compounds are also preferred as the high refractive index cation or anion polymerizable monomer.

  Specific examples of the high refractive index cation or anion polymerizable monomer having an oxetane ring include compounds in which the oxirane ring in the specific examples of the high refractive index cation or anion polymerizable monomer having an oxirane ring is replaced with an oxetane ring. It is done.

  Specific examples of the high refractive index cation or anion polymerizable monomer having a vinyl ether group moiety include, for example, vinyl-2-chloroethyl ether, 4-vinyl ether styrene, hydroquinone divinyl ether, phenyl vinyl ether, bisphenol A divinyl ether, and tetrabromobisphenol A. Examples thereof include divinyl ether, bisphenol F divinyl ether, phenoxyethylene vinyl ether, and p-bromophenoxyethylene vinyl ether.

  In addition, N-vinylcarbazole is also preferable as the high refractive index cationic polymerizable monomer.

The binder in the hologram recording material of the present invention is usually used for the purpose of improving the film formability of the composition before polymerization, film thickness uniformity, storage stability, and the like. As the binder, a dye having a polymerizable group, a polymerizable compound having no dye portion, a polymerization initiator, and a compound having good compatibility with a sensitizing dye 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 may be a reactive binder that can react when radical polymerization or cationic polymerization occurs. In that case, the reactive oligomer which has an ethylenically unsaturated group, an oxirane ring, etc. specifically is preferable.

As described above, the binder of the present invention preferably has a refractive index different from that of the polymerizable compound, and more preferably has a refractive index smaller than that of the polymerizable compound.
For this purpose, the binder preferably does not contain an aryl group, an aromatic heterocyclic group, a chlorine atom, a bromine atom, an iodine atom, or a sulfur atom.

  Specific examples of preferred low refractive index binders in the present invention include acrylate and alpha-alkyl acrylate esters and acidic polymers and interpolymers such as polymethyl methacrylate and polyethyl methacrylate, methyl methacrylate and other (meth) acrylic acids. Alkyl ester copolymers), polyvinyl esters (eg, polyvinyl acetate, polyacetic acid / vinyl acrylate, polyacetic acid / vinyl methacrylate and hydrolyzable polyvinyl acetate), ethylene / vinyl acetate copolymers, saturated and non-polymerized. Saturated polyurethane, butadiene and isoprene polymers and copolymers and polyglycol high molecular weight poly (ethylene oxide) having an average molecular weight of approximately 4,000 to 1,000,000, epoxidized (e.g. having acrylate or methacrylate groups) Poxy compounds), polyamides (eg N-methoxymethyl polyhexamethylene adipamide), cellulose esters (eg cellulose acetate, cellulose acetate succinate and cellulose acetate butyrate), cellulose ethers (eg methyl cellulose, ethyl cellulose, ethyl benzyl) Cellulose), polycarbonate, polyvinyl acetal (eg, polyvinyl butyral and polyvinyl formal), polyvinyl alcohol, polyvinyl pyrrolidone, acid-containing polymers disclosed in US Pat. No. 3,458,311 and US Pat. No. 4,273,857, and And amphoteric polymer binders disclosed in U.S. Pat. No. 4,293,635, more preferably cellulose acetate butyrate polymer, Cellulose acetate lactate polymer, polymethyl methacrylate, acrylic polymers and interpolymers, including methyl methacrylate / methacrylic acid and methyl methacrylate / acrylic acid copolymer, methyl methacrylate / acrylic acid or C2-C4 alkyl methacrylate / Ternary polymer of acrylic acid or methacrylic acid, polyvinyl acetate, polyvinyl acetal, polyvinyl butyral, polyvinyl formal, and mixtures thereof.

  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.

Also, preferred examples include silicon compounds such as poly (dimethylsiloxane) and silicon oils that do not contain aromatics.
In addition, the epoxy oligomer compounds listed below can also be used as the low refractive index reactive binder.

It may be preferable to use a chain transfer agent for the hologram recording material of the present invention. 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 hologram recording material of the present invention in order to improve 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. The dinitroso dimers described in Pazos US Pat. No. 4,168,982 are also useful.

  The plasticizer is used to change the adhesiveness, flexibility, hardness, and other mechanical properties of the hologram 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.

In general, the proportion of each component in the hologram recording material of the present invention is preferably in the range of the following% based on the total mass of the composition.
Binder: preferably 0 to 90% by mass, more preferably 35 to 75% by mass,
Dye having a polymerizable group: preferably 1 to 60%, more preferably 5 to 30%
Polymerizable compound having no dye portion: preferably 0 to 60%, more preferably 15 to 50% by mass,
Polymerization initiator: preferably 0.01 to 30% by mass, more preferably 0.1 to 15% by mass
Sensitizing dye: preferably 0.0001 to 10% by mass, more preferably 0.01 to 5% by mass

The hologram 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, N-amide solvents such as dimethylformamide, and nitrile-based solvents such as acetonitrile.

The hologram recording material of the present invention can be applied directly on the substrate by using a spin coater, roll coater, bar coater or the like, or cast as a film and then laminated on the substrate by a usual method. It can be a hologram recording material.
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.

  Furthermore, a protective layer for blocking oxygen may be formed on the hologram 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 hologram recording material of the present invention is used for holographic optical memory applications, it is more preferable that the hologram recording material does not shrink before and after hologram recording from the viewpoint of improving the S / N ratio during signal reproduction.
Therefore, for example, an expansion agent described in JP-A-2000-86914 is used for the hologram recording material of the present invention, or a shrink-resistant binder described in JP-A-2000-250382, 2000-172154, and JP-A-11-344917 is used. It is also preferable to use it.
In addition, it is also preferable to adjust the interference fringe interval by using a diffusing element described in JP-A-3-46687, 5-204288, JP-A-9-506441 and the like.

  The known ordinary photopolymers such as Patent Documents 1 to 3 and 5 to 8 have a problem that the recording sensitivity is low and the recording speed cannot be obtained. On the other hand, since the hologram recording material of the present invention can be expected to have a large refractive index change even with the same exposure amount, high sensitivity can be expected, and is particularly useful for an optical recording medium (holographic optical memory).

  In addition to the optical recording medium, the hologram recording material of the present invention includes a three-dimensional display hologram, a holographic optical element (HOE, for example, a head-up display (HUD) mounted on an automobile, a pickup lens for an optical disk, a head mount, etc. Displays, color filters for liquid crystals, reflective liquid crystal reflectors, lenses, diffraction gratings, interference filters, optical fiber couplers, optical polarizers for facsimiles, architectural window glass), covers for books, magazines, displays such as POPs, It can be preferably used for credit cards, banknotes, packaging and the like for security purposes for preventing gifts and counterfeiting.

[Example]
In the following, specific examples of the present invention have been described based on experimental results. Of course, the present invention is not limited to these examples.

[Hologram recording method by radical polymerization method]

  As disclosed in JP-A-6-43634, Example 1, sensitizing dye DEAW 0.3%, radical polymerization initiator PI-2, 1.20%, chain transfer agent MBO 1.80%, POEA 46.3% as a monomer, cellulose acetate butyrate as a binder CAB531-1 50.4% was used and dissolved in 3 times mass of methylene chloride (with 2-butanone if necessary) to prepare Comparative Example 1. In Comparative Example 1, instead of reducing POEA to 31.3%, 15% of dye compounds DM-2, DM-15, DM-51 having a polymerizable group of the present invention were added, and then Sample 101, 102 and 103 were prepared.

  This hologram recording material composition comparative example 1, samples 101 to 103 were applied to a glass substrate with a blade so as to have a thickness of 100 μm (overcoated if necessary) to form a photosensitive layer, and then at 40 ° C. The solvent was distilled off by heating and drying for 3 minutes. Furthermore, the hologram recording material comparative example 1 and the samples 101 to 103 were produced by covering the photosensitive layer with a TAC film.

The hologram recording material was exposed and recorded using a YAG laser double wave (532 nm, output 2 W) as a light source by the two-beam optical system for transmission hologram recording shown in FIG. The angle between the object beam and the reference beam is 30 degrees. The beam has a diameter of 0.6 cm and an intensity of 12 mW / cm ² , and the holographic exposure time varies from 0.1 to 100 seconds (irradiation energy ranges from 1.2 to 1200 mJ / cm ² ). And exposed. While exposing the hologram, a He—Ne laser beam of 632 nm was passed through the center of the exposure area at a black angle, and the ratio of the diffracted light to the transmitted light (relative diffraction efficiency) was measured in real time.

  In the hologram recording material comparative example 1, when the exposure energy when the half value of the maximum diffraction efficiency is shown is 1, the exposure energies at 101 to 103 are all as small as 0.40, 0.35, and 0.22. It was found that the hologram recording material of the present invention has a higher sensitivity than the known photopolymer method.

In addition, dyes having a polymerizable group are DM-1, DM-20, DM-22, DM-23, DM-27, DM-30, DM-32, DM-36, DM-38, DM-41, DM. The same effect can be obtained by changing to -44, DM-46, DM-49, or DM-53.
Further, sensitizing dyes are S-1, S-6, S-10, S-11, S-23, S-31, S-34, S-42, S-43, S-45, S-50, The same effect can be obtained by changing to S-58, S-60, S-67, S-71, S-73, S-75, S-76, S-77, and S-81.
Further, the same effect can be obtained even if the radical polymerization initiator is changed to PI-1 or PI-3 to PI-13.
The same effect can be obtained by using M-2, M-3, M-4 instead of POEA as a polymerizable compound having no dye moiety.
The same effect can be obtained even if the binder is changed to polystyrene, polyvinyl acetal, polyvinyl butyral, or polymethyl methacrylate.

[Hologram recording method by cationic polymerization method]

  Sensitizing dye S-67 1%, cationic polymerization initiator PI-5, 10%, M-5 44% as monomer, PMMA 45% as binder, 3-4 times mass of methylene chloride (2-butanone if necessary And Comparative Example 2 was prepared. In Comparative Example 1, instead of reducing M-5 to 30%, 15% of the dye compounds DM-3, DM-21 and DM-52 having a polymerizable group of the present invention were added, and then the same sample 201, 202 and 203 were prepared.

  This hologram recording material composition comparative example 2, samples 201 to 203 were applied to a glass substrate with a blade so as to have a thickness of 100 μm (overcoated if necessary) to form a photosensitive layer, and then at 40 ° C. The solvent was distilled off by heating and drying for 3 minutes. Furthermore, the hologram recording material comparative example 2 and the samples 201 to 203 were produced by covering the photosensitive layer with a TAC film.

The hologram recording material was exposed and recorded using a YAG laser double wave (532 nm, output 2 W) as a light source by the two-beam optical system for transmission hologram recording shown in FIG. The angle between the object beam and the reference beam is 30 degrees. The beam has a diameter of 0.6 cm and an intensity of 12 mW / cm ² , and the holographic exposure time varies from 0.1 to 100 seconds (irradiation energy ranges from 1.2 to 1200 mJ / cm ² ). And exposed. While exposing the hologram, a He—Ne laser beam of 632 nm was passed through the center of the exposure area at a black angle, and the ratio of the diffracted light to the transmitted light (relative diffraction efficiency) was measured in real time.

  In the hologram recording material comparative example 2, when the exposure energy when the half value of the maximum diffraction efficiency is shown as 1, the exposure energy in 201 to 203 is all as small as 0.37, 0.34, and 0.24. It was found that the hologram recording material of the present invention has a higher sensitivity than the known photopolymer method.

The dyes having a polymerizable group are DM-5, DM-16, DM-17, DM-24, DM-28, DM-29, DM-33, DM-37, DM-39, DM-42, DM. The same effect can be obtained by changing to -45, DM-47, DM-50, or DM-54.
Further, sensitizing dyes are S-1, S-6, S-10, S-11, S-23, S-31, S-34, S-42, S-43, S-45, S-50, The same effect can be obtained by changing to S-58, S-60, S-67, S-71, S-73, S-75, S-76, S-77, and S-81.
The same effect can be obtained even when the cationic polymerization initiator is changed to PI-6 to PI-10.
The same effect can be obtained by using M-6 instead of M-5 as a polymerizable compound having no dye moiety.
The same effect can be obtained even if the binder is changed to polystyrene, polyvinyl acetal, polyvinyl butyral, cellulose acetate butyrate, or MO-1.

It is the schematic explaining the two-beam optical system for hologram exposure.

Explanation of symbols

10 YAG laser 12 Laser beam 14 Mirror 20 Beam splitter 22 Beam segment 24 Mirror 26 Spatial filter 40 Beam expander 30 Hologram recording material 28 Sample 32 He-Ne laser beam 34 He-Ne laser 36 Detector 38 Rotating stage

Claims (21)

  A hologram recording material comprising at least one dye having a polymerizable group.   The absorption spectrum of a dye having a polymerizable group has a λmax that is 10 to 200 nm shorter than the hologram reproduction wavelength, ε is 10000 or more, and the molar extinction coefficient at the hologram reproduction wavelength is 100 or less. The hologram recording material according to claim 1, characterized in that:   3. The hologram recording material according to claim 1, further comprising at least a sensitizing dye, a polymerization initiator, and a binder in addition to the dye having the polymerizable group.   The hologram recording material according to claim 3, further comprising at least one polymerizable compound having no dye portion.   The hologram recording material according to claim 4, wherein at least one of the polymerizable compounds having no dye portion is a liquid having a boiling point of 100 ° C. or higher.   6. The hologram recording material according to claim 3, wherein the dye having a polymerizable group has a higher refractive index at the hologram reproduction wavelength than that of the binder.   7. The hologram recording material according to claim 4, wherein a refractive index at a hologram reproduction wavelength is higher for a polymerizable compound having no dye portion than for a binder.   The polymerizable compound having no dye portion contains at least one aryl group, aromatic heterocyclic group, chlorine atom, bromine atom, iodine atom, or sulfur atom, and the binder does not contain them. The hologram recording material according to claim 4.   A sensitizing dye excited state generated by absorbing light by holographic recording light irradiation using the hologram recording material according to claim 4 activates a polymerization initiator by electron transfer or energy transfer, and forms a polymerizable group. Polymerization of a polymerizable compound having no pigment part and a pigment having a dye having a polymerizable group having a polymerizable group in a bright interference part where the light is stronger is mainly transferred, A hologram recording method characterized in that interference fringes are recorded by refractive index modulation due to binder being mainly driven into a weak interference dark part.   10. The hologram recording method according to claim 9, wherein the polymerization reaction is any one of radical polymerization, cationic polymerization, and anionic polymerization.   When the polymerizable group of the polymerizable compound having the polymerizable group or the polymerizable compound not having the dye portion is a radical polymerization, the polymerizable group may be an acryloyl group, a methacryloyl group, a styryl group, or a vinyl group. An ethylenically unsaturated group moiety, and when the polymerization is cationic polymerization or anionic polymerization, the polymerizable group has any one of an oxirane ring, an oxetane ring, a vinyl ether group, and an N-vinylcarbazole moiety. The hologram recording material of 1-8.   The polymerization initiator is 1) a ketone polymerization initiator, 2) an organic peroxide polymerization initiator, 3) a bisimidazole polymerization initiator, 4) a trihalomethyl-substituted triazine polymerization initiator, and 5) a diazonium salt polymerization. Initiator, 6) diaryl iodonium salt polymerization initiator, 7) sulfonium salt polymerization initiator, 8) triphenylalkyl borate polymerization initiator, 9) diaryl iodonium organoboron complex polymerization initiator, 10) sulfonium Organic boron complex polymerization initiators, 11) Cationic dyes Organic boron complex polymerization initiators, 12) Anionic dye onium salt complex polymerization initiators, 13) Metal arene complex polymerization initiators, 14) Sulfonate esters The hologram recording material according to claim 1, wherein the hologram recording material is a polymerization initiator.   The polymerization initiator according to claim 12, wherein the polymerization initiator is a radical polymerization initiator that generates radicals, 1) a ketone polymerization initiator, 2) an organic peroxide polymerization initiator, 3) a bisimidazole polymerization initiator, 4 3) a trihalomethyl-substituted triazine polymerization initiator, 5) a diazonium salt polymerization initiator, 6) a diaryliodonium salt polymerization initiator, 7) a sulfonium salt polymerization initiator, 8) a triphenylalkyl borate polymerization initiator. 9) diaryliodonium organic boron complex polymerization initiator, 10) sulfonium organic boron complex polymerization initiator, 11) cationic dye organic boron complex polymerization initiator, 12) anionic dye onium salt complex polymerization initiator, 13. The hologram recording material according to claim 12, wherein the hologram recording material is any one of a metal arene complex polymerization initiator.   The polymerization initiator according to claim 12, wherein the polymerization initiator is a cationic polymerization initiator that generates an acid, 4) a trihalomethyl-substituted triazine polymerization initiator, 5) a diazonium salt polymerization initiator, and 6) a diaryl iodonium salt polymerization initiator. The hologram recording material according to claim 12, wherein the hologram recording material is any one of: 7) a sulfonium salt polymerization initiator, 13) a metal arene complex polymerization initiator, and 14) a sulfonate ester polymerization initiator.   The hologram recording material according to claim 3, wherein the sensitizing dye has a molar extinction coefficient at a hologram recording wavelength of 1 or more and 2000 or less.   9. A sensitizing dye is added such that the film thickness of the hologram recording material is 100 μm or more and the light transmittance of the hologram recording wavelength is 10% or more and 99% or less. The hologram recording material according to 11 to 15. A hologram recording material used in the hologram recording method according to claim 9 or 10.   The hologram recording material according to claim 1, wherein the hologram recording is a system in which hologram recording cannot be rewritten.   A hologram recording method comprising performing multiple recording 10 times or more using the hologram recording material according to claim 1.   An optical recording medium comprising the hologram recording material according to claim 1.   19. An optical recording medium, wherein the hologram recording material according to claim 1 is stored in a light shielding cartridge during storage.

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