JP3122647B2 - Information recording medium and information recording / reproducing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium capable of recording, as visible information, information recording by a voltage application exposure recording method using a photosensitive member or information recording by a voltage application, and an information recording / reproducing method thereof.

[0002]

2. Description of the Related Art In the conventional electrophotographic technique, there is known an information recording medium in which a liquid crystal cell in which a nematic liquid crystal is sealed on a photoconductive layer and an insulating layer for liquid crystal alignment are sequentially laminated between a pair of electrodes. It is known that a liquid crystal is aligned by lowering the resistance of a photoconductive layer in an information exposure section by applying information while a voltage is applied between the electrodes, and obtaining a visible image using a deflecting plate.

This information recording medium needs to be formed into cells in order to enclose the liquid crystal. In addition, in order to perform twist nematic alignment at the initial stage, an insulating film in which both surfaces of the cells are subjected to an alignment treatment by rubbing treatment or the like is provided. In order to keep the gap constant, it is necessary to mix spacers, so that a high-resolution image cannot be obtained. In addition, there is an optical problem because a rigid and transparent support is required for producing a gap or a cell.
Further, there is a problem that the alignment treatment in the initial state cannot be detected unless a polarizing plate is used for reading.

On the other hand, recently, a liquid crystal layer in a liquid crystal cell has been developed by using a polymer-dispersed liquid crystal, and such a medium is held in a state sandwiched between two substrates having ITO electrodes. This medium is used as a substrate / ITO electrode /
When used in a method of recording electrostatic information on the liquid crystal layer by a discharge phenomenon corresponding to the information light by exposing at the time of voltage application in the state of facing the photoreceptor with a liquid crystal layer configuration, the polymer dispersion type There is a problem that the liquid crystal oozes out on the surface of the liquid crystal and causes noise at the time of recording information. In addition, by forming the ITO electrode directly on the liquid crystal layer, the substrate / ITO electrode / liquid crystal layer / ITO electrode is formed. ,
When information is recorded by applying a voltage between the two electrodes to orient the liquid crystal layer, the liquid crystal oozes out, and the I of the surface layer also increases.
There is a problem that cracks, embossments, etc. occur on the TO electrode and the conductivity is reduced. Further, when the electrode layer and the liquid crystal layer are formed by the laminating method, there are problems of uniformity of the gap and noise due to the spacer.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an information recording medium and an information recording / reproducing method which can record information accurately without using a liquid crystal cell and which can easily reproduce information. In particular, it is an object of the present invention to provide an information recording medium and an information recording / reproducing method which do not cause image unevenness due to oozing of liquid crystal when using a polymer dispersed liquid crystal as an information recording layer.

[0006]

Means for Solving the Problems The information recording medium of the present invention is an information recording medium in which an information recording layer comprising a smectic liquid crystal phase and an ultraviolet curable resin phase is provided as an uppermost layer on an electrode layer, The information recording layer has a structure in which resin particles are filled in a smectic liquid crystal phase forming a continuous layer, and its outer surface layer is formed as a skin layer made of only an ultraviolet curable resin.

The method for recording and reproducing information on an information recording medium according to the present invention is directed to an information recording medium having an information recording layer comprising a smectic liquid crystal phase and an ultraviolet curable resin phase as an uppermost layer on an electrode layer. An information recording medium in which the information recording layer has a structure in which resin particles are filled in a smectic liquid crystal phase forming a continuous layer and an outer surface layer of which is formed on a skin layer made of only an ultraviolet curable resin; A photoconductor provided with a photoconductive layer is arranged facing or non-contacting with a photoconductor,
After exposing information from the photoconductor or the information recording medium side while applying a voltage between both electrodes of the information recording medium and the photoconductor, and performing information recording by orienting the smectic liquid crystal phase according to the information, The information recording medium is separated, and information recorded on the information recording medium is reproduced as visible information by transmitted light or reflected light.

Hereinafter, an information recording medium and an information recording / reproducing method of the present invention will be described. FIG. 1A is a diagram for schematically explaining a cross section of the information recording medium of the present invention, in which 3 is an information recording medium, 11 is an information recording layer, 13 is an electrode layer,
Reference numeral 15 denotes a substrate. The electrode layer 13 only needs to have one or both of them transparent, and has a specific resistance of 10 ⁶ Ω · cm.
The following metal thin-film conductive films, inorganic metal oxide conductive films, and organic conductive films such as quaternary ammonium salts are used. The electrode layer 13 is formed by evaporation, sputtering, CVD, coating, plating,
It is formed by a method such as dipping or electrolytic polymerization. Further, the film thickness needs to be changed depending on the electric characteristics of the material constituting the electrode and the applied voltage at the time of information recording.
For example, an ITO film has a thickness of about 100 to 3000, and is formed on the entire surface between the information recording layers or in accordance with the formation pattern of the information recording layers.

The substrate 15 includes a card, a film, a tape,
It supports the information recording medium having the shape of a disk or the like in terms of strength. It is not necessary to provide the information recording layer when the information recording layer has a supporting property. The material and thickness are not particularly limited as long as they have, and for example, a flexible plastic film or a rigid body such as glass, a plastic sheet, or a card is used. Specifically, when the information recording medium takes the form of a flexible film, tape, disk, or card, a flexible plastic film is used, and when strength is required, a rigid sheet or glass is used. And the like.

On the other side of the substrate on which the electrode layer 13 is provided, a layer having an antireflection effect is laminated as necessary, or the transparent substrate is formed to a thickness capable of exhibiting the antireflection effect. The antireflection property may be imparted by adjusting or further combining them.

Next, the information recording layer 11 is composed of a smectic liquid crystal phase and a resin phase. As a liquid crystal material, a smectic liquid crystal alone or a mixture of a smectic liquid crystal, a nematic liquid crystal, and a cholesteric liquid crystal can be used. Although it is possible, it is preferable to use a smectic liquid crystal from the viewpoint of maintaining the orientation of the liquid crystal and retaining information permanently, that is, from the viewpoint of so-called memory property.

The smectic liquid crystal includes a liquid crystal substance exhibiting a smectic A phase such as a cyanobiphenyl-based, cyanoterphenyl-based, phenylester-based, and fluorine-based liquid crystal substance having a long carbon chain at a terminal group of a substance exhibiting liquid crystallinity, and a ferroelectric substance. A liquid crystal material exhibiting a smectic C phase used as a liquid crystal;
Alternatively, a liquid crystal substance exhibiting smectic H, G, E, F, or the like can be given.

Further, a nematic liquid crystal may be mixed with a smectic liquid crystal, for example, a Schiff base type, an azoxy type,
Azo, phenyl benzoate, phenyl cyclohexyl, biphenyl, terphenyl, phenylcyclohexane, phenylpyridine,
Known nematic liquid crystals such as phenyl oxazine type, polycyclic ethane type, phenyl cyclohexene type, cyclohexyl pyrimidine type, phenyl type and tolan type can be used.

When a liquid crystal material is selected, a material having a different direction of the refractive index is preferable because contrast can be obtained.

The material forming the resin phase is a UV-curable resin which is compatible with the liquid crystal material in the form of a monomer or oligomer, or is compatible with a common solvent with the liquid crystal material in the form of a monomer or oligomer. Those having solubility can be preferably used.

Examples of such UV-curable resins include acrylic acid esters and methacrylic acid esters. In the form of monomers and oligomers, for example, dipentaerythritol hexaacrylate, trimethylolpropane triacrylate, polyethylene glycol diacrylate , Polypropylene glycol diacrylate, isocyanuric acid (ethylene oxide modified) triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetraacrylate, neopentyl glycol diacrylate, hexanediol diacrylate, and other polyfunctional monomers or urethanes , Ester-based oligomers, nonylphenol-modified acrylates, N-vinyl-2-pyrrolidone,
Monofunctional monomers or oligomers such as 2-hydroxy-3-phenoxypropyl acrylate are exemplified.

As the solvent, there is no particular problem as long as it is a common solvent. For example, hydrocarbon solvents such as xylene, halogenated hydrocarbon solvents such as chloroform, and methyl cellosolve are examples. And ether solvents such as dioxane.

Examples of the photocuring agent include 2-hydroxy-2-methyl-1-phenylpropan-1-one (“Darocur 1173” manufactured by Merck) and 1-hydroxycyclohexylphenylketone (“Irgacure” manufactured by Ciba Geigy). 184 "), 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one (" Darocure 1116 "manufactured by Merck), benzyldimethylketal (" Irgacure 65 "manufactured by Ciba-Geigy)
1 "), 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1 (" Irgacure 907 ", manufactured by Ciba-Geigy), 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd.) A mixture of “Kayacure DETX”) and ethyl p-dimethylaminobenzoate (“Kayacure EPA” manufactured by Nippon Kayaku Co., Ltd.), isopropylthioxanthone (“Kuntacure I” manufactured by Ward Brekinsop)
A mixture of "TX" and ethyl p-dimethylaminobenzoate, and the like. Liquid 2-hydroxy-2-methyl-1-phenylpropan-1-one is a liquid crystal, and a polymer-forming monomer or oligomer. It is particularly preferable in terms of compatibility with the resin forming material.

The ratio between the liquid crystal and the resin-forming material is preferably such that the content of the liquid crystal is 10 to 90% by weight, preferably 40 to 80% by weight, and less than 10% by weight. Even if the liquid crystal phase is oriented by the information recording, the light transmittance is low, and if it exceeds 90% by weight, phenomena such as oozing of the liquid crystal occur, which is not preferable because image unevenness occurs. When a large amount of liquid crystal is present in the information recording layer, the contrast ratio can be improved and the operating voltage can be reduced.

The method for forming the information recording layer is as follows: a mixed solution of a resin forming material and liquid crystal is coated on the electrode layer with a blade coater,
It is formed by applying and curing by a coating method such as a roll coater or a spin coater. In addition,
If necessary, a leveling agent may be added to improve the applicability of the solution and improve the surface properties.

Further, it is necessary to heat the liquid crystal to a temperature higher than a temperature at which the liquid crystal maintains an isotropic phase, and to completely dissolve the liquid crystal and the ultraviolet-curable resin-forming material. When the information recording layer is cured by ultraviolet light at a temperature lower than the temperature at which the liquid crystal exhibits an isotropic phase, a problem arises due to partial phase separation between the liquid crystal and the ultraviolet-curable resin material. That is, the liquid crystal domain grows too much, the skin layer is not completely formed on the surface of the information recording layer, and the liquid crystal bleeds out or the ultraviolet curable resin is matted, so that it is difficult to take in information accurately. Is not preferred. Further, the ultraviolet curable resin may not be able to hold the liquid crystal and may not even form the information recording layer. On the other hand, when evaporating the solvent, if heating is necessary to maintain the isotropic phase, there is a problem that the wettability to the electrode layer is reduced and a uniform information recording layer cannot be obtained.

Further, a fluorine-based surfactant is added for the purpose of maintaining wettability to the electrode layer. Examples of such a fluorine-based surfactant include, for example, Sumitomo 3M Co., Ltd.
Manufactured by Florad FC-430 and Florad FC-43
1, N- (n-propyl) -N- (β-acryloxyethyl) -perfluorooctylsulfonic acid amide [EF-125M manufactured by Mitsubishi Materials Corporation], N- (n-propyl) -N- (β -Methacryloxyethyl) -perfluorooctylsulfonic acid amide [Mitsubishi Materials Corporation
EF-135M], perfluorooctanesulfonic acid [EF-101 from Mitsubishi Materials Corporation], perfluorocaprylic acid [EF-20 from Mitsubishi Materials Corporation]
1], N- (n-propyl) -N-perfluorooctanesulfonic acid amide ethanol [Mitsubishi Materials Corporation]
EF-121 manufactured by Mitsubishi Materials Corporation.
102, EF-103, EF-104, EF-1
05, EF-112, EF-121, EF-12
2A, EF-122B, EF-122C, EF-
122A3, EF-123A, EF-123B, EF-132, EF-301, EF-303, E
F-305, EF-306A, EF-501, E
F-700, EF-201, EF-204, EF
-351, EF-352, EF-801, EF-
802, EF-125DS, EF-1200, E
FL-L102, EF-L155, EF-L174,
EF-L215 and the like. Also, 3- (2-perfluorohexyl) ethoxy-1,2-dihydroxypropane [MF-100 manufactured by Mitsubishi Materials Corporation], N
-N-propyl-N-2,3-dihydroxypropyl perfluorooctylsulfonamide [MF-110 manufactured by Mitsubishi Materials Corporation], 3- (2-perfluorohexyl) ethoxy-1,2-epoxypropane [Mitsubishi Materials MF-120], Nn-propyl-N
-2,3-epoxypropyl perfluorooctylsulfonamide [MF-130 manufactured by Mitsubishi Materials Corporation],
Perfluorohexyl ethylene [Mitsubishi Materials Corporation
MF-140], N- [3-trimethoxysilyl) propyl] perfluoroheptylcarboxylic acid amide [MF-150 from Mitsubishi Materials Corporation], N- [3-trimethoxysilyl) propyl] perfluoroheptylsulfone Amide [MF-160 manufactured by Mitsubishi Materials Corporation] and the like. The fluorine-based surfactant is used in a ratio of 0.1 to 20% by weight based on the total amount of the liquid crystal and the resin-forming material.

The solid content concentration in the coating solution for forming the information recording layer is preferably 10 to 60% by weight, and upon curing, the curing conditions such as the type of resin, the concentration, the temperature of the coating layer, and the conditions for irradiating ultraviolet rays are appropriately adjusted. By setting
A skin layer consisting of only a resin layer having no liquid crystal phase as an outer surface layer can be favorably formed.

Since the thickness of the information recording layer affects the resolution, the thickness after drying is 0.1 μm to 10 μm, preferably 3 μm.
The operating voltage can be reduced while maintaining high resolution. If the film thickness is too thin, the contrast of the information recording section is low, and if it is too thick, the operating voltage is undesirably high.

By forming the skin layer on the outer surface of the information recording layer, it is possible to increase the use ratio of the liquid crystal in the information recording layer and to prevent the liquid crystal from seeping out.

Hereinafter, the photosensitive member of the present invention will be described. The photoconductor can be a single-layer photoconductor or a laminated photoconductor. A single-layer photoreceptor is formed by laminating a mixture of a charge-generating substance and a charge-transporting substance on an electrode. This is a type in which a layer and a charge transport layer are sequentially laminated on an electrode.

The photoreceptor used in the present invention has the following general formula (1):

[0028]

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(Wherein X in the formula may be the same or different selected from hydrogen, lower alkyl group, lower alkoxy group, nitro group, sulfonic group, hydroxyl group, carboxyl group, halogen atom, and n is An integer of 0 to 3, and R is a hydrocarbon ring group, a heterocyclic group, or an alkyl group which may be substituted.) As a charge generating substance, and an electron accepting substance. In the case of a single-layer type photoreceptor, it is added together with a bisazo compound, and in the case of a multilayer type photoreceptor, it is added together with a bisazo type compound to the charge generation layer or added together with the charge generation layer and added to the charge transport layer. Is also added.

The photoreceptor used in the present invention can not only provide electrostatic information corresponding to the information pattern with high sensitivity and high contrast to the charge holding medium, but also provide the photoreceptor after the photoreceptor is prepared. Even during the course, the contrast ratio is excellent in stability over time since the dark potential does not increase.

First, bisazo compounds which can be preferably used in the present invention are exemplified below by combinations of the substituents in the above general formula (1).

[0032]

[Table 1]

Among them, preferred bisazo compounds are exemplified below.

[0034]

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Next, the charge transporting material forming the charge transporting layer is a material having a good property of transporting the charge generated by the charge generating material, for example, hydrazone type, pyrazoline type and PVK type.
System, carbazole system, oxazole system, triazole system, aromatic amine system, amine system, triphenylmethane system, polycyclic aromatic compound system, etc. it can. Among them, compounds represented by the following formulas (24) to (33) are preferred.

[0036]

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[0037]

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Next, as the electron accepting substance added to the charge generation layer or the charge generation layer and the charge transport layer,
4,7-trinitrofluorenone, tetrafluoro-P
-Benzoquinone, tetracyanoquinodimethane, triphenylmethane, maleic anhydride, hexacyanobutadiene and the like can be used.

Next, a method for manufacturing a photoreceptor will be described. First, the laminated photoreceptor is prepared by mixing a charge generating substance and an electron accepting substance in a ratio of 0.001 part by weight to 10 parts by weight of an electron accepting substance with respect to 1 part by weight of the charge generating substance. To form a charge generation layer by coating and drying on an electrode, and then dissolving or dispersing a charge transport material in a medium as appropriate on the charge generation layer to form a charge transport layer. Alternatively, the electron-accepting substance is mixed at a ratio of 0.001 part by weight to 10 parts by weight with respect to 1 part by weight of the charge transporting substance, dispersed in a suitable medium, dissolved and coated, dried, coated and dried. To form a charge transport layer. The charge generation layer has a thickness of 0.1 to 10 μm after drying, and the charge transport layer has a thickness of 1 to 50 μm.
m.

In a single-layer type photoreceptor, the charge generating substance and the charge transporting substance are preferably mixed in a ratio (parts by weight) of 1: 100 to 100: 100, and the electron accepting substance is mixed with the charge generating substance and the charge transporting substance. 0.1 parts per 1 part by weight of the total amount of the substance.
It is advisable to mix them in a ratio of 001 parts by weight to 10 parts by weight, and they are dispersed or dissolved in a medium, coated on an electrode, and dried to form a layer. The thickness is preferably 1 to 50 μm.

A charge transfer complex may be formed by forming a complex between the charge generating substance and the charge transporting substance. Normal,
The photoreceptor has photosensitivity determined by the light absorption characteristics of the charge generating material. However, when a charge generating material and a charge transporting material are mixed to form a complex, the light absorption characteristics change. For example, polyvinyl carbazole (PVK) is used in the ultraviolet region. Although only trinitrofluorenone (TNF) feels only around 400 nm wavelength, the PVK-TNF complex becomes sensitive up to 650 nm wavelength range.

In both the single-layer type and the laminated type, a binder can be used to form the photoconductive layer. Examples of the binder include a silicone resin, a styrene-butadiene copolymer resin, an epoxy resin, and an acrylic resin. , A saturated or unsaturated polyester resin, a polycarbonate resin, a polyvinyl acetal resin, a phenol resin, a polymethyl methacrylate (PMMA) resin, a melamine resin, a polyimide resin, a vinyl chloride resin, a vinyl acetate resin, and the like. It is preferable to use 0.1 to 10 parts by weight for 1 part by weight of each material of the transport substance. In the case where the charge generating substance and the charge transporting substance show the role of the binder itself, the binder is unnecessary.

As the solvent, dichloroethane, 1,1,
2-trichloroethane, monochlorobenzene, tetrahydrofuran, cyclohexane, dioxane, 1,2,3
-Trichloropropane, ethyl cellosolve, 1,1,
Examples thereof include 1, -trichloroethane, methyl ethyl ketone, chloroform, and toluene.

As a coating method, a coating method such as a blade coating method, a dipping method, and a spinner coating method can be used.

In the photoreceptor of the present invention, it is not always necessary to provide the photoreceptor in order to cause a decrease in sensitivity, but a photoconductive layer may be laminated on the electrode via a charge injection preventing layer as means for suppressing a change with time.

The charge injection preventing layer is provided on at least one or both surfaces of the photoconductive layer, a dark current (for example, charge injection from an electrode) when a voltage is applied to the photoconductive layer, that is, when the photoconductive layer is not exposed. Nevertheless, it is provided to prevent a phenomenon in which charges move in the photoconductive layer as if exposed.

The charge injection preventing layer is classified into two types, one utilizing a so-called tunneling effect and one utilizing a rectification effect. First, in a device utilizing the so-called tunneling effect, current does not flow to the photoconductive layer or the insulating layer surface due to the charge injection preventing layer only by applying a voltage, but when light is incident, it corresponds to an incident portion. In the charge injection preventing layer, a high electric field is applied due to the presence of one of the charges (electrons or holes) generated in the photoconductive layer, causing a tunnel effect and causing a current to flow through the charge injection preventing layer. .

Such a charge injection preventing layer has an inorganic insulating property.
Film, organic insulating polymer film, insulating monolayer, etc.
Or, they are formed by laminating them, and as an inorganic insulating film
Is, for example, As_TwoO_Three , B_TwoO_Three, Bi_TwoO_Three , CdS, CaO, CeO_Two,
Cr_TwoO_Three , CoO, GeO_Two, HfO_Two, Fe _TwoO_Three , La_TwoO_Three , MgO, Mn
O_Two, Nd_TwoO_Three , Nb_TwoO_Five , PbO, Sb_TwoO_Three , SiO_Two, SeO_Two, Ta_TwoO
_Five , TiO_Two, WO_Three , V_TwoO_Five, Y_TwoO_Five, Y_TwoO_Three, ZrO_Two, BaTiO_Three, Al
_TwoO_Three , Bi_TwoTiO_Five , CaO-SrO, CaO-Y_TwoO_Three, Cr-SiO, LiTa
O_Three, PbTiO_Three, PbZrO_Three, ZrO_Two-Co, ZrO_Two-SiO_Two , AlN, B
N, NbN, Si_ThreeN_Four , TaN, TiN, VN, ZrN, SiC, TiC
 , WC, Al_FourC_Three Glow discharge, evaporation, sputtering etc.
And the like. The thickness of this layer prevents charge injection
It is used in consideration of insulation properties and tunnel effect.
Determined for each material.

Next, the charge injection preventing layer utilizing the rectifying effect is formed by providing a charge transporting layer having a charge transporting ability of a polarity opposite to that of the electrode substrate utilizing the rectifying effect. As such a charge injection preventing layer, an inorganic photoconductive layer,
It is formed of an organic photoconductive layer and an organic-inorganic hybrid type photoconductive layer, and has a thickness of about 0.1 to 10 μm. Specifically, when the electrode is negative, amorphous silicon photoconductive layer doped with B, Al, Ga, In, etc., amorphous selenium photoconductive layer, polyvinyl carbazole photoconductive layer, or oxadiazole, pyrazoline, polyvinyl carbazole, Stilbene, anthracene, naphthalene, tridiphenylmethane, triphenylmethane, azine, amine,
An organic charge transport layer formed by dispersing an aromatic amine or the like in a resin, and P, N, As, Sb, B
amorphous silicon photoconductive layer doped with i, etc., Zn
An O photoconductive layer, a polyvinyl carbazole-trinitrofluorenone organic photoconductive layer, and the like are formed by a method such as glow discharge, vapor deposition, sputtering, CVD, and coating.

The photoreceptor support is not particularly limited in thickness and material as long as it has a certain strength capable of supporting the photoreceptor. For example, a flexible plastic film, metal foil, paper Alternatively, a rigid body such as a glass, a plastic sheet, or a metal plate (which can also serve as an electrode) is used. However, when used in a device that records information by irradiating light from the photoconductor side, it is naturally necessary to have the property of transmitting that light.For example, when using natural light as incident light and using it in a camera that enters from the photoconductor side Has a thickness of 1
A transparent glass plate of about mm or a plastic film or sheet is used.

The photoreceptor electrode is formed on the photoreceptor support except when a metal support is used for the photoreceptor support,
The material is not limited as long as the specific resistance value is 10 ⁶ Ω · cm or less, and examples thereof include an inorganic metal conductive film, an inorganic metal oxide conductive film, and an organic conductive film such as a quaternary ammonium salt. Such a photoreceptor electrode is formed on a photoreceptor support by vapor deposition, sputtering, CVD, coating, plating, dipping, electrolytic polymerization, or the like. The film thickness needs to be changed depending on the electrical characteristics of the material constituting the photoreceptor electrode and the applied voltage when recording information. For example, in the case of aluminum, it is about 100 to 3000. This photoreceptor electrode also needs the above-mentioned optical characteristics when it is necessary to transmit information light, similarly to the support. For example, if the information light is visible light (400 to 700 nm), the IT
Transparent electrodes such as O (In ₂ O ₃ -SnO ₂ ), SnO _2, etc., which are formed by sputtering, vapor deposition, or inking and coating fine powders thereof with a binder, Au, Al,
Translucent electrodes made of Ag, Ni, Cr, etc. by evaporation or sputtering, tetracyanoquinodimethane (TCN
Q), an organic transparent electrode with a coating of polyacetylene or the like is used.

The above-mentioned electrode material can also be used when the information light is infrared (700 nm or more) light. In some cases, a colored visible light absorbing electrode can be used to cut off visible light.

Further, when the information light is ultraviolet light (400 nm or less), the above electrode material can be basically used. However, the electrode substrate material which absorbs ultraviolet light (organic polymer material,
Soda glass) is not preferred, and a material that transmits ultraviolet light, such as quartz glass, is preferred.

It is preferable to form an antireflection film on the light incident surface. This anti-reflection film can be formed by depositing an inorganic material such as magnesium fluoride, titanium oxide or the like in a single layer or by lamination by a sputtering method or the like.

Next, a method for recording information on an information recording medium according to the present invention will be described. FIG. 2 is a diagram for explaining a method of recording information on the information recording medium shown in FIG. 1 (a), wherein 1 is a photoconductor, 5 is a photoconductive layer support, 7 is a photoconductor electrode, 9
Is a photoconductive layer, and 17 is a power supply.

First, a 1000-mm thick indium tin oxide (ITO) film was formed on a photoconductive layer support 5 made of glass having a thickness of 1 mm.
A transparent photoreceptor electrode 7 made of
The photoconductor 1 is formed by forming about m photoconductive layers 9.

As shown in FIG. 2A, an information recording medium 3 is arranged on the photosensitive member 1 with a gap of about 10 μm. Then, a voltage is applied between the electrodes 7 and 13 by the power supply 17 as shown in FIG. In a dark place, the photoconductive layer 9 is a high-resistance body.

In this state, when light 18 is incident from the photoreceptor 1 side, the photoconductive layer 9 in the portion where the light is incident becomes conductive and has a low resistance, and an electric field acts on the information recording layer. , The liquid crystal orientation occurs.

When forming the information charges, since the operating voltage and the range vary depending on the liquid crystal, when setting the applied voltage and the applied voltage time, the voltage distribution between the photosensitive member, the air gap, and the information recording medium is required. May be appropriately set, and the voltage distribution applied to the information recording layer may be set in the operating voltage region.

The method of recording information on an information recording medium according to the present invention is capable of performing planar analog recording and obtaining high resolution because alignment at the liquid crystal level is obtained, and the exposure pattern is variable depending on the alignment of the liquid crystal phase. It is visualized and held.

The information input method includes a method using a high-resolution electrostatic camera and a recording method using a laser. The information light may be incident from the photoconductor side or may be incident from the information recording medium side. First, a high-resolution electrostatic camera forms a recording member by a photoreceptor 1 and an information recording medium 3 instead of a photographic film used in a normal camera, and may use an optical shutter. An electric shutter may also be used.

Further, optical information is separated into R, G, and B light components by a prism and a color filter, extracted as parallel light, and R, G, and B separated into three information recording media.
Color photography can be performed by forming frames or by arranging R, G, and B images on one plane to form one frame in one set.

As a recording method using a laser, an argon laser (514.488 nm) is used as a light source,
A helium-neon laser (633 nm) or a semiconductor laser (780 nm, 810 nm, or the like) can be used. The photosensitive member and the information recording medium are brought into close contact with each other in a planar state, or they are opposed to each other at a certain interval, and a voltage is applied. In this state, laser exposure corresponding to the image signal, character signal, code signal, and line drawing signal is performed by scanning. Analog recording such as an image is performed by modulating the light intensity of a laser, and digital recording such as characters, codes, and line drawings is performed by ON-OFF control of a laser beam. In the case where halftone dots are formed in an image, the laser light is formed by performing dot generator ON-OFF control. Note that the spectral characteristics of the photoconductive layer in the photoreceptor need not be panchromatic, but may be any as long as they have sensitivity to the wavelength of the laser light source.

In addition, instead of the photoreceptor, corona charging, or a method in which a voltage is applied by a needle electrode or a pattern electrode in a contact or non-contact state, or information is recorded by an ion printer using an ion head. You can also.

The information recorded by the orientation of the liquid crystal is visible information that can be read visually, but can be enlarged and read by a reflection type projector, and further reflected by laser scanning or CCD. Information can be read with high accuracy by reading with light or transmitted light.

The information recording medium of the present invention records electrostatic information in a state visualized by the orientation of liquid crystal, and has a memory property. This memory property is erased when the liquid crystal is heated to a temperature near its isotropic phase transition, and can be reused.

Next, another embodiment of the information recording medium will be described. FIG. 1B is a diagram showing a cross section of another embodiment of the information recording medium of the present invention, in which 13 'is an electrode layer, and the same reference numerals as those in FIG. 1A indicate the same contents.

In this information recording medium, an electrode layer 13 'is further provided in a pattern on the information recording layer surface of the information recording medium. Such an electrode layer 13 '
The material described for the electrode layer 13 described above can be used. For example, an ITO layer may be provided by a sputtering method or a vapor deposition method.

Normally, when a mixture of a curable resin and a liquid crystal is used and the resin is cured to form a film, the liquid crystal oozes out on the film surface. For example, even if ITO is laminated by sputtering or vapor deposition, Cracks occur in the ITO film, causing a decrease in conductivity.

An information recording medium according to another embodiment of the present invention comprises:
Since there is a skin layer made of only an ultraviolet curable resin on the surface of the information recording layer, there is no bleeding of liquid crystal, and even if ITO or the like is directly provided on the information recording layer by a vacuum evaporation method or a sputtering method, the electrode layer Cracks do not occur, and the conductivity does not decrease. In addition, heat resistance and spatter resistance can be improved. Further, since the electrode layer is integrated with the information recording layer as compared with the first information recording medium, the gap between the electrodes can be made uniform.

To record information on the information recording medium of another embodiment, a voltage is applied between the electrodes 13 and 13 ', and the electrode 13'
This is performed by orienting the liquid crystal layer at the site where (1) exists.
Alternatively, the electrode layers 13 and 13 'may be arranged in a matrix, and a pattern may be recorded by manipulating the voltage. Both electrodes may be provided uniformly on both sides of the information recording layer, and a low voltage may be applied between the two electrodes. In advance, the information recording layer may be heated in a pattern using a laser beam or the like, and the operating voltage at the heated portion may be reduced to about the applied voltage to record the laser beam pattern. For information reproduction, for example, when using transmitted light, light is transmitted in the information recording unit, but light is scattered in a part where information is not recorded,
The contrast with the information recording unit can be obtained.

[0072]

The information recording medium of the present invention holds liquid crystal in the information recording layer and does not cause liquid crystal bleeding on its surface. When used in the method, there is no disturbance of information recording by liquid crystal on the surface of the information recording layer, and electrostatic information without image unevenness can be recorded. Also, since the information recording layer can be uniformly thinned by a coating technique, the gap between the information charges formed on the information recording layer and the electrode layer can be made uniform and small, and a large-area information recording medium can be manufactured. Yes, high-resolution images can be recorded and reproduced.

In the case of the information recording medium of another embodiment, since the bleeding of the liquid crystal on the surface of the information recording layer can be prevented, the electrode layer such as an ITO film can be formed by a vapor deposition method or the like. There is no generation of wrinkles, cracks and the like, and deterioration of conductivity can be prevented. Further, since the electrode layer can be provided directly on the information recording layer, the gap between both electrodes can be made uniform.

The information recording medium of the present invention can easily obtain an electro-optical effect, and can record and store analog information. When an electric field is not applied by an information charge, the liquid crystal phase is opaque due to light scattering. When an electric field is applied by an information charge, the liquid crystal phase is oriented and the information recording section is made transparent. Therefore, the optical system for reading can be simplified.

Examples will be described below. In the examples, "part" means "part by weight" and "%" means "% by weight".

Example 1 Multifunctional monomer (dipentaerythritol hexaacrylate, manufactured by Toa Gosei Chemical Co., Ltd., M-40)
0) 40 parts, photocuring initiator (2-hydroxy-2-methyl-1-phenylpropan-1-one, manufactured by Merck, Darocur 1173) 2 parts, smectic liquid crystal (S-6 manufactured by BDH) 60 parts, Surfactant (Fluorard FC-43
(Manufactured by Sumitomo 3M Co., Ltd.) 3 parts in 195 parts of xylene, and an ITO film is formed on a glass substrate (thickness: 1.1 mm) by sputtering with a thickness of about 2000.
The film was coated on the film side using a blade coater, dried at 50 ° C. for 3 minutes, and then dried at 50 ° C. for 3 minutes under reduced pressure.
Immediately, ultraviolet rays of 300 mJ / cm ² were irradiated to cure the polyfunctional monomer. The thickness was 6 μm.

After the liquid crystal was extracted from the cross section of the information recording layer using hot methanol and dried, the internal structure was observed with a scanning electron microscope (manufactured by Hitachi, Ltd., S-800, 10000 ×). However, as shown in FIG. 4, the surface of the layer is covered with a UV-curable resin having a thickness of 0.6 μm, and inside the layer, a resin particle phase having a particle size of 0.1 μm is contained in a liquid crystal phase forming a continuous layer. It can be seen that it has a filled structure.

Next, on the cured information recording layer, an ITO film was formed as an upper electrode by a sputtering method for about 500.
The information recording medium of the present invention was produced.

A lead wire is attached between both electrodes of the medium,
A voltage of 400 V DC was applied to the terminals for 0.1 second. Before the application of the voltage, the transmittance of the light of 633 nm was 40%, but after the application of the voltage, it became 80%.

This transparent state was maintained at room temperature for one year or more and showed good memory properties. Next, the information recording medium to which the voltage was applied was placed on a hot plate at 60 ° C., and after 10 seconds, immediately cooled to room temperature. The liquid crystal did not exude, and the whole returned to the scattering state before voltage application. ,
Reuse is possible.

[0080]

Example 2 The smectic liquid crystal (BD) in Example 1
In the same manner as in Example 1 except that a smectic liquid crystal (S1 manufactured by BDH) was used instead of S-6 manufactured by Company H, 105 parts of xylene was used, and the coating layer temperature was dried at 32 ° C. An information recording medium was manufactured and tested in the same manner as in Example 1. As a result, the same performance as in Example 1 was shown.

[0081]

Embodiment 3 (Preparation of photoreceptor) The following formula is used as a charge generation material.

[0082]

Embedded image

3 parts of a bisazo pigment and 1 part of a polyvinyl acetal resin were mixed with dioxane: cyclohexane = 1: 1.
A solution obtained by sufficiently dispersing a 100 g solution having a solid content of 2% with a mixed solvent by a ball mill was used for a glass substrate having an ITO transparent electrode (film thickness: about 500, resistance value: 80 Ω / sq.).
The coating was applied to the TO side using a 2 mil gap blade coater and dried at 100 ° C. for 1 hour to form a 0.3 μm-thick charge generating layer.

Next, 15 parts of p-diethylaminobenzaldehyde-N-phenyl-benzylhydrazone as a charge transporting material and 10 parts of a polycarbonate resin (trade name: Iupilon S-100, manufactured by Mitsubishi Gas Chemical Co., Ltd.) were added to dichloromethane, 1,1: 1. , 2-Trichloroethane = 4: 6 to adjust the solid content to 17.8%.
The resultant was coated on the above-mentioned charge generating layer with a blade coater having a mill gap thickness, and dried at 80 ° C. for 2 hours to form a charge transporting layer having a thickness of 10 μm, thereby producing an organic photoreceptor.

On the other hand, in the information recording medium in Example 1, an information recording medium without an upper electrode was produced, and the photosensitive member produced above was used as a spacer with a 9 μm-thick polyester film as a spacer. A DC voltage of 800 V was applied with the medium side being negative.

With the voltage applied, the illuminance 10
Exposure using a 00-lux halogen lamp as a light source is 0.
This was performed for 1 second, and after the exposure was completed, the information recording medium was taken out, and the information recording was completed. The exposed portion became transparent, and the transmittance of this portion was 90%.

A normal camera was used as an exposure method, and an exposure f = 1.4, a shutter speed of 1/60 sec., And outdoor and daytime photocopies were taken with a voltage of 800 V applied through a gap in the same manner as described above. Was done. When the information recording medium was taken out after the exposure, an image having gradation was formed.

Further, the medium was read by a film scanner using a CCD sensor, and output by a sublimation transfer printer. As a result, a hard copy having gradation was obtained.

[0089]

Example 4 (Preparation of photoreceptor) As a charge generating material, 3 parts of the bisazo pigment represented by the above [Chemical Formula 6] and a mixed resin of a vinyl chloride resin and a vinyl acetate resin (DENKA CORPORATION)
100%), and a solid content of 1.3% with a mixed solvent of dioxane: cyclohexane = 1: 1.
g The solution obtained by sufficiently dispersing the solution with a ball mill is
A glass substrate having a transparent electrode (thickness: about 500, resistance value: 80 Ω / sq.) Was coated on the ITO side using a blade coater with a 2 mil gap, dried at 100 ° C. for 1 hour,
A charge generation layer having a thickness of 0.3 μm was formed.

Next, as a charge transport material, 1,1-bis (4-diethylaminophenyl-1,3-butadiene 1
0 parts and polystyrene resin (manufactured by Denka Corporation: trade name MW-
1) 1 part was adjusted to a solid content of 15% with a mixed solvent of dichloromethane: 1,1,2-trichloroethane = 4: 6, and this solution was coated on the charge generating layer with a blade coater having a gap thickness of 5 mil. The resultant was applied and dried at 80 ° C. for 2 hours to form a charge transporting layer having a thickness of 20 μm, thereby producing an organic photoconductor.

On the other hand, in the information recording medium of Example 2, an information recording medium without an upper electrode was produced, and the photosensitive member produced above was used as a spacer with a polyester film having a thickness of 9 μm as a spacer, and the information recording side was positive. A DC voltage of 800 V was applied with the medium side being negative.

With the voltage applied, the illuminance 10
Exposure using a 00-lux halogen lamp as a light source is 0.
This was performed for 1 second, and after the exposure was completed, the information recording medium was taken out, and the information recording was completed. The exposed portion became transparent, and the transmittance of this portion was 90%.

Further, a normal camera is used as an exposure method, and an illuminance of 2000 lux and an exposure f =
4. The subject was photographed at a shutter speed of 1/30 second. When the information recording medium was taken out after the exposure, an image having gradation was formed.

Further, the medium was read by a film scanner using a CCD sensor, and output by a sublimation transfer printer. As a result, a hard copy having gradation was obtained.

[0095]

Comparative Example In place of the resin forming material in Example 1,
A thermosetting resin, bisphenol A resin (Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd.) and an aliphatic curing agent (B-002, manufactured by Ibid.) Were used and cured by heating to 60 ° C. An information recording medium was manufactured in the same manner as in Example 1.

When information was recorded on this information recording medium in the same manner as in Example 1, stains occurred on the information recording surface,
It was found that liquid crystal bleeding occurred.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an information recording medium according to the present invention.

FIG. 2 is a diagram for explaining a method of recording information on an information recording medium according to the present invention.

FIG. 3 shows a grain structure in a cross section of an information recording layer of the information recording medium of the present invention, and is a scanning electron microscope photograph instead of a drawing.

[Explanation of symbols]

1 is a photoreceptor, 3 is an information recording medium, 5 is a photoconductive layer support,
7 is a photoreceptor electrode, 9 is a photoconductive layer, 11 is an information recording layer, 1
3, 13 'are electrode layers, 15 is substrate, 17 is power supply, 18 is pattern exposure

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-196229 (JP, A) JP-A-2-4215 (JP, A) JP-A-3-155525 (JP, A) JP-A-2- 6924 (JP, A) JP-A-4-86807 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/13 505 G02F 1/1334

Claims (3)

(57) [Claims] 1. An information recording medium having an information recording layer comprising a smectic liquid crystal phase and an ultraviolet curable resin phase as an uppermost layer on an electrode layer, wherein the information recording layer forms a continuous layer. An information recording medium having a structure in which resin particles are filled in a phase and an outer surface layer of which is formed as a skin layer made of only an ultraviolet curable resin. 2. An information recording medium in which an information recording layer comprising a smectic liquid crystal phase and an ultraviolet curable resin phase is provided as an uppermost layer on an electrode layer, wherein the information recording layer forms a continuous layer. An information recording medium having a structure in which resin particles are filled in a phase and the outer surface layer of which is formed of a skin layer made of only an ultraviolet curable resin, and a photoreceptor having a photoconductive layer provided on an electrode layer. Alternatively, information is recorded by aligning the smectic liquid crystal phase in accordance with the information by exposing information from the photoconductor or the information recording medium side while applying a voltage between both electrodes of the information recording medium and the photoconductor, in a non-contact arrangement. After performing, the photoconductor and the information recording medium are separated,
An information recording / reproducing method, wherein recorded information on an information recording medium is reproduced as visible information by transmitted light or reflected light. 3. The information recording / reproducing method according to claim 2 , wherein the photoconductor contains a compound represented by the following general formula (1) in its photoconductive layer. General formula (1) (However, X in the formula may be the same or different selected from hydrogen, lower alkyl group, lower alkoxy group, nitro group, sulfonic acid group, hydroxyl group, carboxyl group, halogen atom, and n is 0 to 3) And R is an optionally substituted hydrocarbon ring group, heterocyclic group, or alkyl group.)