JP3187575B2 - Information recording medium manufacturing method 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 a method for manufacturing an information recording medium and an information recording / reproducing method capable of obtaining, as visible information, electrostatic information recorded by an exposure recording method at the time of applying a voltage. The present invention relates to a method for manufacturing an information recording medium having a uniform thickness and excellent contrast, and an information recording / reproducing method.

[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 when recording information. In the case of using the method of recording information by applying a voltage between the two electrodes to form the substrate / ITO electrode / liquid crystal layer / ITO electrode and aligning the liquid crystal layer, the liquid crystal oozes out, and the ITO of the surface layer is also formed. A problem arises in that the electrodes are cracked, embossed, etc., and the conductivity is reduced.

[0005] The applicant of the present invention used an ultraviolet curable resin as a resin for forming the information recording layer in this type of medium, whereby the liquid crystal phase and the ultraviolet curable resin phase were dispersed inside the information recording layer. It has been found that it has a structure, and its outer surface can be formed as an ultraviolet-curable resin skin layer, and has previously filed an application (Japanese Patent Application No. 4-24580). Since the surface of the information recording layer is formed only of the resin layer, the liquid crystal does not seep out, the information recording using the optical sensor can be performed without noise, and the information recording layer is formed on the resin layer by a sputtering method. This makes it possible to directly form an electrode layer such as an ITO film. However, in this type of information recording medium, since a spacer or the like is not used, if the film thickness is not exactly uniform, contrast unevenness and accurate recording cannot be performed at the time of information recording, which causes shading and the like.

[0006]

The present invention relates to an improvement in a method for manufacturing an information recording medium using a polymer dispersed liquid crystal as a liquid crystal layer, wherein the information recording layer has a uniform film thickness and the contrast is low. It is an object of the present invention to provide a method for manufacturing an information recording medium that enables accurate and accurate information recording.

[0007]

According to the present invention, there is provided a method of manufacturing an information recording medium, comprising: an information recording medium having an information recording layer comprising a liquid crystal phase and a resin phase on an electrode layer; After dissolving the resin-forming material and the fluorine-based surfactant in a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate, the solution is applied onto the electrode layer, and then cured by irradiation with ultraviolet light to cure the outer surface. It is characterized in that an information recording layer is formed by forming a skin layer made of only an ultraviolet curable resin.

According to the information recording / reproducing method of the present invention, in an information recording medium having an information recording layer comprising a liquid crystal phase and a resin phase on an electrode layer, the information recording layer is formed of a liquid crystal, an ultraviolet curable resin-forming material, and fluorine. After applying a mixed solution of a surfactant and a solvent having a relative evaporation rate to n-butyl acetate smaller than 2 on the electrode layer, the mixture is cured by irradiation with ultraviolet light, and the outer surface thereof is formed only of an ultraviolet-curable resin. An information recording medium that is formed on a skin layer made of, and an optical sensor having a photoconductive layer provided on an electrode layer are disposed facing each other in contact or non-contact, and between the information recording medium and both electrodes of the optical sensor. Information exposure is performed while applying voltage, and information is recorded by orienting the liquid crystal phase according to the information. When reproducing the recorded information, the information is reproduced as visible information using transmitted light or reflected light. And it features.

First, an information recording medium manufactured according to the present invention will be described. FIG. 1 is a diagram schematically illustrating a cross section of an information recording medium. In FIG.
1 is an information recording layer, 13 is an electrode layer, and 15 is a substrate.

The information recording layer 11 is composed of a liquid crystal phase and a resin phase.
Nematic liquid crystal, cholesteric liquid crystal, or a mixture thereof can be used, but it is preferable to use a smectic liquid crystal from the viewpoint of so-called memory property that maintains the orientation of the liquid crystal and permanently retains information.

The smectic liquid crystal includes a liquid crystal material exhibiting a smectic A phase such as a cyanobiphenyl-based, cyanoterphenyl-based, phenylester-based, or fluorine-based one having a long carbon chain at the terminal group of a substance exhibiting liquid crystallinity. 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 used, and the memory property can be improved by mixing with a smectic or cholesteric liquid crystal. For example, Schiff base type, azoxy type, azo type, phenyl benzoate type, phenyl cyclohexylate Known nematic liquid crystals such as ester, biphenyl, terphenyl, phenylcyclohexane, phenylpyridine, phenyloxazine, polycyclic ethane, phenylcyclohexene, cyclohexylpyrimidine, phenyl and tolane can be used. Further, a mixture obtained by mixing a polyvinyl alcohol or the like with a liquid crystal material to form a microcapsule 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.

As a material for forming the resin phase, a solvent-soluble thermosetting resin having compatibility with a common solvent with the liquid crystal material, for example, an acrylic resin, a methacrylic resin, a polyester resin, a polystyrene resin, and mainly these materials It is also possible to use an epoxy resin, a silicone resin, or the like, such as a copolymer, which is a UV-curable resin that is compatible with the liquid crystal material in a monomer or oligomer state, or a monomer or oligomer state And those having compatibility with a common solvent with the liquid crystal material can be preferably used.

Examples of such an ultraviolet-curable resin 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.

[0014] The solvent is a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate, and is a solvent common to liquid crystal, an ultraviolet-curable resin-forming material, a photocuring agent, and a fluorine-based surfactant. That is necessary. The “solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate” is described, for example, in Yuji Harazaki, “Easily Understandable Coating Technology”, pp. 217-221, published by Riko Publishing Co., Ltd. Volatile at a certain temperature, Wherein R is less than 2.

[0015] Solvents that can be used in the present invention include:
Xylene (R = 0.76), cyclohexanone (R =
0.32) or the like having a relatively low evaporation rate is preferable.
Examples of the solvent include halogenated hydrocarbon solvents such as chloroform, alcohol derivative solvents such as methyl cellosolve, and ether solvents such as dioxane. In addition, specifically, methyl alcohol,
Denatured ethanol, isopropanol, n-propanol, sec-butanol, isobutanol, n-butanol, methylisobutylcarbinol, diisobutylcarbinol, hexylene glycol, acetic acid-sec-butanol, isobutyl acetate (98%), n-butyl acetate , Methyl aluminum acetate, aluminum acetate (95% isomer mixture), ethyl lactate, methyl oxitol, ethyl oxitol, isopropyl oxytol, methyl oxytol acetate, ethyl oxytol acetate, butyl oxytol, methyl dioxitol, ethyl Dioxitol, butyl dioxitol, butyl dioxytol acetate, methyl isobutyl ketone, ethyl amyl ketone, Pent-O-xone (ME-6K), methyl cyclohexanone, Sobuchiruketon, diacetone alcohol, isophorone, 1,4-dioxane, perchlorethylene, dichloropropane, 2-nitropropane,
Toluene, SBP100 / 140, rubber solvent, xylene, SBP140 / 165, SBP6, SBP11, S
hellsolA, white spirit (LOWS),
ShellsolE, ShellsolTD, White Spirit (115 ° F ignition), ShellsolT,
ShellsolAB, Distilate, Sol
vent300, ShellsolN, Shellso
lRA, ShellsolK, ShellsolR, S
solvent350 and the like.

Examples of the photocuring agent include 2-hydroxy-2-methyl-1-phenylpropan-1-one ("Darocure 1173" manufactured by Ciba-Geigy) and 1-hydroxycyclohexylphenyl ketone ("Irgacure" manufactured by Ciba-Geigy). 184 "), 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-1-
ON (“Darocur 1116” manufactured by Ciba-Geigy), benzyldimethyl ketal (“Irgacure 651” manufactured by Ciba-Geigy), 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropanone-1 (Ciba -"Irgacure 907" manufactured by Geigy Corporation), 2,4-diethylthioxanthone ("Kayacure DE" manufactured by Nippon Kayaku Co., Ltd.)
TX ") and ethyl p-dimethylaminobenzoate (" Kayacure EPA "manufactured by Nippon Kayaku Co., Ltd.), and isopropylthioxanthone (" Kuntacure ITX "manufactured by Ward Brekinsop Co., Ltd.) and ethyl p-dimethylaminobenzoate Mixtures and the like can be mentioned, and liquid 2-hydroxy-2-methyl-1-phenylpropan-1-one is particularly preferable in view of compatibility with a liquid crystal material, a polymer-forming monomer or an oligomer.

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

The information recording layer is made opaque due to light scattering when no electric field is applied, by making the light refractive index of the liquid crystal phase and that of the resin phase substantially the same. The phase is oriented and the information recording portion can be made transparent. The information reproducing device does not require a deflecting plate, and the reading optical system can be simplified.

In the present invention, a fluorine-based surfactant is added for the purpose of forming a skin layer composed of only a resin on the surface of the information recording layer as well as wettability to the electrode layer. Examples of such a fluorine-based surfactant include Florad FC-430, Florad FC-431, and N- (n-propyl) -N- (β-acryloxyethyl) -perfluoro manufactured by Sumitomo 3M Co., Ltd. Octylsulfonic acid amide [EF-125M manufactured by Mitsubishi Materials Corporation], N
-(N-propyl) -N- (β-methacryloxyethyl) -perfluorooctylsulfonic acid amide [EF-135M manufactured by Mitsubishi Materials Corporation], perfluorooctanesulfonic acid [EF-10 manufactured by Mitsubishi Materials Corporation]
1], perfluorocaprylic acid [Mitsubishi Materials Corporation
EF-201], N- (n-propyl) -N-perfluorooctanesulfonic acid amide ethanol [EF-121 from Mitsubishi Materials Corp.], and EF-102 and EF-103 from Mitsubishi Materials Corp. , EF-10
4, EF-105, EF-112, EF-12
1, EF-122A, EF-122B, EF-1
22C, EF-122A3, EF-123A, E
F-123B, EF-132, EF-301, E
F-303, EF-305, EF-306A, E
F-501, EF-700, EF-201, EF
-204, EF-351, EF-352, EF-
801, EF-802, EF-125DS, EF
-1200, EF-L102, EF-L155, EF-L174, and EF-L215. Also, 3- (2-perfluorohexyl) ethoxy-1,
2-dihydroxypropane [M manufactured by Mitsubishi Materials Corporation
F-100], Nn-propyl-N-2,3-dihydroxypropylperfluorooctylsulfonamide [MF-110 manufactured by Mitsubishi Materials Corporation], 3- (2-
Perfluorohexyl) ethoxy-1,2-epoxypropane [MF-120 manufactured by Mitsubishi Materials Corporation], N-
n-propyl-N-2,3-epoxypropylperfluorooctylsulfonamide [MF-130 manufactured by Mitsubishi Materials Corporation], perfluorohexylethylene [MF-140 manufactured by Mitsubishi Materials Corporation], N- [3- Trimethoxysilyl) propyl] perfluoroheptylcarboxylic acid amide [MF-150 manufactured by Mitsubishi Materials Corporation],
N- [3-trimethoxysilyl) propyl] perfluoroheptylsulfonamide [M manufactured by Mitsubishi Materials Corporation
F-160]. The fluorine-based surfactant is used in an amount of 0.1 to 20% by weight based on the total amount of the liquid crystal and the resin-forming material.
Used in proportions. If necessary, a leveling agent may be added to improve the applicability of the solution and improve the surface properties.

Next, a method of forming the information recording layer will be described step by step. (1) Mixing a liquid crystal, a resin-forming material, a photopolymerization initiator, and a surfactant with a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate to obtain a solid content of 10 to 60% by weight. Make a solution. Solvent dilution is 1 to 500 cps (2
0 ° C.), preferably 10 to 200 cps (20 ° C.). If the viscosity is low, the coating liquid flows and the film thickness after coating cannot be maintained, and if the viscosity is high, leveling becomes difficult. Further, the liquid crystal is heated and dissolved at a temperature higher than the temperature at which the liquid crystal maintains an isotropic phase, preferably within a temperature range of + 10 ° C. of the isotropic phase transition point. At this time, the gelled material, dust and the like of the ultraviolet-curable resin-forming material present in the solution are removed by filtration. The presence of gelled matter, dust and the like causes noise as an information recording medium.

(2) Next, the mixed solution is applied uniformly on the electrode layer at room temperature by a coating method such as a spin coater, a bar coater, a blade coater, or a roll coater.

(3) After the coating layer is heated to a temperature at which the liquid crystal maintains an isotropic phase or more, the isotropic phase transition point is preferably ± 10.
The temperature is kept in the range of ° C. and the solvent is evaporated off. If the solvent is evaporated and dried when the mixed solution is heated to a temperature equal to or higher than the isotropic phase temperature, the mixed solution undergoes phase separation, and a uniform film is not formed. Therefore, in the present invention, a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate is used. If the relative evaporation rate is greater than 2, evaporation will be too fast, causing the above problem. Usually, as long as the solvent can be dissolved by heating up to 70 ° C., even if the solvent has R of 0.3 or more and 1 or less, there is no problem, and xylene (R = 0.7) may be used. When heating at 70 ° C. or more is required to perform the heating, a solvent having a R of less than 0.3;
For example, cyclohexanone (R = 0.2) may be used.

If the temperature of the coating layer is lower than the isotropic phase transition temperature by 10 ° C. or more, there is a problem that the liquid crystal and the ultraviolet curable resin material undergo phase separation before curing. 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 seeps out, or the ultraviolet curable resin is matted, making it difficult to capture 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. When the temperature is equal to or higher than the isotropic phase transition point + 10 ° C., the detailed reason is unknown, but the phase separation between the liquid crystal phase and the resin phase in the information recording layer becomes unclear.

(4) In order to complete the removal of the solvent, the drying treatment is preferably performed in two stages, food drying and vacuum drying, thereby preventing unevenness of the information recording layer surface due to the flow of air. In addition, interference fringes can be prevented.

(5) Next, the dried coating layer is subjected to UV
The coating layer is irradiated with ultraviolet light by using a lamp and cured.
An information recording layer having excellent phase separation between a liquid crystal phase and a resin phase can be obtained by irradiating with ultraviolet light having a wavelength portion of 1% or more from 00 nm to 400 nm at an energy of 0.1 mJ / cm ² or more. .

(6) The average thickness of the information recording layer formed in this manner is 1 μm to 30 μm. If the thickness is too large, the operating voltage becomes high.
In general, it is preferable to reduce the film thickness in order to increase the sensitivity, and to increase the film thickness in order to increase the contrast. In order to improve the sensitivity and the contrast ratio, the film thickness is preferably 3 μm to 20 μm, more preferably 5 μm to 10 μm. Thus, the operating voltage can be reduced while maintaining high contrast. Further, in the information recording medium of the present invention, spacers such as glass beads used in ordinary liquid crystal cells cause noise. Therefore, it is necessary that the thickness of the information recording layer be accurately and uniformly applied, and this can be achieved by the above-described forming method. If the film thickness is not uniform, it may cause contrast unevenness, and may also cause shading during information recording. When the information recording layer is formed by the above method, the thickness of the information recording layer is determined to be 5 μm to 10 μm.
In the case of m, the surface roughness Ra can be set to 200 ° or less, there is no contrast unevenness, and no shading phenomenon can occur even during information recording.

If the phase separation between the liquid crystal phase and the resin phase is incomplete in the fine structure inside the information recording layer, there arises a problem that the contrast cannot be obtained. In addition, if the phase separation is incomplete, the information recording layer itself will have low resistance, and when information is recorded by the action of an electric field by electrostatic information using an optical sensor, a voltage is effectively applied to the liquid crystal phase in the information recording layer. However, there is a problem that the liquid crystal drive becomes slow and the sensitivity is lowered. Further, if the phase separation is incomplete, the UV-curable resin-forming material may be converted to a UV-containing UV-containing resin.
Irradiation with a lamp causes non-uniform shrinkage due to unnecessary heating, causing a serious problem that a critically uniform information recording layer cannot be formed as an information recording medium.

When the information recording layer is formed as described above,
A skin layer having a thickness of about 0.6 μm is formed on the surface of the information recording layer, and the inside of the information recording layer has a primary particle size of 0.0
It can have a structure in which resin particles of 3 μm to 0.3 μm are filled and a liquid crystal phase is communicated therebetween. When a polyfunctional ultraviolet-curable resin material having an average molecular weight / average functional group parameter of 160 or less is used as the ultraviolet-curable resin-forming material, the surface skin layer has excellent durability. And can be. By forming a durable skin layer on the surface of the information recording layer, it is possible to increase the use ratio of the liquid crystal in the information recording layer, and there is no bleeding of the liquid crystal onto the surface of the information recording layer. Can be eliminated, and a high-quality image can be obtained.

A mixed solution of the resin-forming material and the liquid crystal is applied and dried, and then a smooth substrate such as a quartz glass plate is placed on the applied surface, and the ultraviolet light is applied while uniformly pressing the applied layer. When the curable resin is cured by irradiation, and then the substrate is peeled off to obtain an information recording medium, an information recording layer with less variation in light transmittance can be obtained.

The electrode layer 13 may be transparent or opaque, but has a specific resistance of 10 ⁶ Ω · cm or less, a conductive film of an inorganic metal oxide such as indium tin oxide, a quaternary ammonium salt, or the like. Organic conductive film. Electrode layer is 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 may be transparent or opaque, but strongly supports an information recording medium having a shape such as a card, a film, a tape, or a disk. If it has, there is no need to provide it, but the material and thickness are not particularly limited as long as it has a certain strength capable of supporting the information recording layer. 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 shape of a flexible film, tape, disk, or card,
When a flexible plastic film is used and strength is required, a rigid sheet or an inorganic material such as glass is used.

When information is reproduced by transmitted light, the electrodes and the substrate need to have transparency. In this case, the other surface of the substrate on which the electrode layer is provided may be provided as necessary. The anti-reflection property may be imparted by laminating layers having an anti-reflection effect, or by adjusting the transparent substrate to a film thickness capable of exhibiting the anti-reflection effect, or by combining both.

Next, a method of recording information on an information recording medium will be described. Information is recorded on the information recording medium of the present invention by using a method such as an optical sensor, heat, laser, or corona charging. Preferably, information is recorded using an optical sensor. Such an optical sensor is formed by laminating an electrode layer and a photoconductive layer on a transparent substrate, and the photoconductive layer is a single layer having both a charge generation function and a charge transport function according to information light. And a laminate type in which a charge generation layer and a charge transport layer are sequentially laminated on an electrode layer. The photoconductive layer generally has a function of generating photocarriers (electrons and holes) at an irradiated portion when irradiated with light, and the carriers can move the layer width. This layer has a remarkable effect when present. An example of such an optical sensor is the optical sensor described in Japanese Patent Application No. 4-287983. In the optical sensor described in this publication, the electric field or electric charge applied to the information recording medium at the time of light irradiation is amplified with light irradiation, and the conductivity is maintained when a voltage is continuously applied even after the light irradiation is completed. It has a function of sustaining and continuously applying an electric field or a charge amount to the information recording medium.

FIG. 2 shows an information recording apparatus incorporating an optical sensor. In the figure, 1 is an optical sensor, 3 is an information recording medium, 1
3 ″ is a photosensor electrode, 14 is a photoconductive layer, 11 is an information recording layer, 13 is an information recording medium electrode, 15 is a substrate, 19 is a spacer, 21 is a light source, 22 is a shutter having a driving mechanism, and 23 is a pulse generator. (Power supply), 24 indicates a dark box.

First, a voltage is applied between the two electrodes 13 and 13 ″ by a power supply. In recording on the information recording medium, the information recording medium is, for example, a resistance heater (not shown) embedded in its support. When the liquid crystal is heated to a temperature indicating a liquid crystal phase, the memory property of the liquid crystal can be further improved.

When information light is incident from the light source 21 while a voltage is applied by the pulse generator 23 between the electrodes 13 and 13 ″, the photocarriers generated in the photoconductive layer 14 in the portion where the light is incident are applied to both electrodes. Move to the interface on the information recording layer 11 side by the electric field formed by the above, the voltage is redistributed, the liquid crystal phase in the information recording layer 11 is oriented, and recording according to the pattern of information light is performed. Has a positive pole on the photoreceptor side and a negative pole on the information recording medium side. Needless to say, the polarity is set according to the discharge characteristics of the optical sensor.

In setting the applied voltage, since some liquid crystal materials operate at a low voltage, the voltage distribution of the optical sensor, the air gap, and the information recording medium is appropriately set and applied to the information recording layer. The voltage may be set in its operating voltage range. Information recording by this optical sensor can be performed in the form of planar analog recording, and the liquid crystal phase can be oriented at the level of electrostatic charge.
A high resolution similar to that of silver salt photography is obtained, and the exposure pattern is kept visible by the orientation of the liquid crystal phase.

As a method of inputting information to the information recording medium of the present invention, there are a method using a camera and a method using a laser. As a method using a camera, an information recording medium is used instead of a photographic film used in a normal camera, and a recording member is used. An optical shutter can be used, and an electric shutter can also be used. It is a good thing. Further, the optical information is separated into R, G, and B light components by a prism and a color filter, extracted as parallel light, and one frame is formed by three sets of R, G, and B information recording media, or on one plane. By arranging the R, G, and B images side by side to form one frame in one set, color photography can also be performed.

As a recording method using a laser,
As a light source, an argon laser (514.488n)
m), helium-neon laser (633 nm), semiconductor laser (780 nm, 810 nm, etc.) can be used,
Laser exposure corresponding to an image signal, a character signal, a code signal, and a 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.

As shown in FIG. 3, when the electrostatic information recorded on the information recording medium is reproduced by the transmitted light, the light A is transmitted because the liquid crystal is oriented in the direction of the electric field in the information recording portion. On the other hand, the light B is scattered in a portion where information is not recorded, and a contrast with the information recording portion can be obtained.
The information recorded by the orientation of the liquid crystal is visible information that can be visually read with transmitted light, but can also be read by enlarging with a projector, and is read with laser scanning or transmitted light using a CCD. Thus, information can be read with high accuracy, and scattered light can be prevented by using a schlieren optical system as needed. Further, it can be read by reflected light. If contrast is a problem, a reflective layer may be provided on any of the layers.

The information recording medium is used after being cut in an appropriate size in the layer width direction in accordance with the use mode, and the inside of the information recording layer is exposed at the cut surface.
Bleeding of the liquid crystal phase occurs during storage. When this bleeding phenomenon occurs, there occurs a problem that when information is recorded, accurate information recording cannot be performed at the end of the information recording medium. In order to prevent this, after the information recording medium is cut into an appropriate shape, a resin layer may be similarly laminated on the cut surface by a coating method or a laminating method to protect the cut surface.

The information recording medium of the present invention records electrostatic information in a state visualized by the orientation of liquid crystal.
By selecting a combination of liquid crystal and resin, once oriented,
The visualized information is not erased, but is given a memory property. The memory may be erased by heating to a high temperature near the isotropic phase transition, and can be used again for information recording.

[0043]

The method of manufacturing an information recording medium according to the present invention can form an information recording layer with a uniform film thickness, does not cause contrast unevenness due to non-uniformity of the film thickness, and is free from information unevenness. Shading can be prevented from occurring even during recording.

Further, since the liquid crystal does not bleed out on the surface of the information recording layer, if it is used in an information recording method combined with an optical sensor, the information recording due to the bleeding out of the liquid crystal on the surface of the information recording layer can be prevented. It is possible to record electrostatic information without disturbance and without image unevenness. In addition, since the information recording layer can be uniformly thinned by a coating technique, a large-area information recording medium can be manufactured, and a high-resolution image can be recorded and reproduced. Hereinafter, examples will be described. In the examples, “parts” indicates “parts by weight” and “%” indicates “% by weight”.

[0045]

EXAMPLE An indium tin oxide (ITO) film having a thickness of 1000 .ANG. Was formed on a sufficiently cleaned glass substrate having a thickness of 1.1 mm by a sputtering method to obtain an electrode layer. On the electrode, 40 parts of a polyfunctional monomer (dipentaerythritol hexaacrylate, manufactured by Toa Gosei Chemical Co., Ltd., M-400, molecular weight / functional group = 117), a photocuring initiator (2-hydroxy-2-methyl-) 1-phenylpropan-1-one, manufactured by Ciba-Geigy: 2 parts of Darocur 1173;-Smectic liquid crystal (S-6: manufactured by BDH): 60 parts;-Surfactant (manufactured by Sumitomo 3M: Florard FC) −
430) A solution prepared by uniformly dissolving 3 parts in 105 parts of xylene (special grade reagent, manufactured by Junsei Chemical Co., Ltd.) was applied using a blade coater, and immediately dried at 50 ° C. for 3 minutes, and then dried at 50 ° C.
After drying under reduced pressure for 3 minutes, immediately 600 mJ / cm ²
UV light of 6 μm and the surface roughness Ra = 5
An information recording layer of 0 ° was formed to obtain an information recording medium of the present invention. The transmittance of this information recording medium at 600 nm light is 4
It was 0%.

(Preparation of Optical Sensor) The following structure is used as a charge generating agent

[0047]

Embedded image

Using 3 parts of a fluorenone azo pigment (manufactured by Nippon Kosaku Dye Co., Ltd.), 1 part of a polyester resin (manufactured by Toyobo Co., Byron 200), and a mixed solvent of 1,4-dioxane: cyclohexanone = 1: 1, A 100 g solution having a solid content of 2% was sufficiently dispersed with a paint shaker to form a coating liquid, and an IT having a film thickness of 500 ° and a resistance value of 80 Ω / cm ² was used.
A glass substrate having an O film is coated on the ITO side using a blade coater with a gap of 2 mils,
After drying for a time, a charge generation layer having a thickness of 0.3 μm was laminated.

On this charge generation layer, a charge transport agent having the following structure

[0050]

Embedded image

25 parts of paradimethylstilbene, 5 parts of a polystyrene resin (HRM-3, manufactured by Denka), 1,
102 parts of 1,2-trichloroethane, dichloromethane 6
8 parts of the coating liquid, coated using a blade coater, dried at 80 ° C. for 2 hours, laminated with a charge transport layer, and formed into a 20 μm thick photoconductive layer composed of a charge generation layer and a charge transport layer. A layer was provided to obtain an optical sensor.

Next, the obtained optical sensor and the information recording medium of the present invention produced as described above are arranged facing each other with a 10 μm PET film as a spacer, and incorporated in the recording apparatus of FIG. Is positive and the information recording medium side is negative, and a DC voltage of 800 V is applied. With the voltage applied, exposure was performed for 0.1 second using a halogen lamp having an illuminance of 1000 lux as a light source from the optical sensor side. After the exposure was completed, the information recording medium was taken out, and the information recording was completed. The exposed part becomes transparent, the transmittance of this part becomes 80%,
The contrast ratio was excellent.

An ordinary camera was used as an exposure method, and an object was photographed outdoors and in the daytime at an exposure f = 1.4 and a shutter speed of 1/60 second with a voltage of 600 V applied. After the exposure, when the information recording medium was taken out, it was possible to see through an image having no noise and gradation. The information recording medium was read by a scanner using a CCD line sensor, and further output by a sublimation printer. As a result, a high-resolution hard copy having gradation was obtained.

After the liquid crystal is extracted from the cut surface of the information recording layer of the information recording medium of the present invention with hot methanol and dried, a scanning electron microscope (manufactured by Hitachi, Ltd., S-
(800, 10000 times)
The surface of the layer is covered with a 0.6 μm thick UV curable resin,
It was found that the inside of the layer had a structure filled with resin particles having a particle size of 0.1 μm.

[0055] Further, in the information recording layer, an ITO film having a film thickness of 500Å was formed by sputtering as the upper electrode, was measured for the liquid crystal driving resistance, V ₁₀ (transmittance at light at 600nm of 10% 200 V, V ₉₀ (600
(voltage at which the transmittance for light at 10 nm becomes 10%) is 260 V
Met.

Further, in the method for producing the information recording medium,
Cyclohexanone instead of xylene as a solvent used as well to produce an information recording medium, the measured liquid driven, V ₁₀ is 200V, V ₉₀ was 260 V.

[0057]

Comparative Example In the method for producing an information recording medium in Example 1, ethyl acetate (R =
Using 4.2), coating was performed on the ITO film in the same manner.

However, while the coating layer was dried at 50 ° C. for 3 minutes, phase separation between the liquid crystal phase and the resin phase occurred, and a coating film in which the liquid crystal phase and the resin phase were uniformly dispersed was not formed.
The information recording medium could not be formed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a cross section of an information recording medium according to the present invention.

FIG. 2 is a schematic diagram of an information recording device using an optical sensor.

FIG. 3 is a diagram for explaining a method of reproducing recorded information on an information recording medium.

[Explanation of symbols]

1 is an optical sensor, 3 is an information recording medium, 11 is an information recording layer, 13 and 13 ″ are electrode layers, 14 is a photoconductive layer, 15 is a substrate, 19 is a spacer, 21 is a light source, and 22 is a shutter having a driving mechanism. , 23 are a pulse generator (power supply), 24 is a dark box, A is transmitted light, and B is scattered light.

Claims (2)

(57) [Claims] 1. A method for manufacturing an information recording medium having an information recording layer comprising a liquid crystal phase and a resin phase on an electrode layer,
After dissolving the liquid crystal, the ultraviolet-curable resin-forming material and the fluorine-based surfactant in a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate, the solution is applied onto the electrode layer, and then cured by irradiation with ultraviolet light. Forming an information recording layer by forming an outer surface of the outer layer on a skin layer made of only an ultraviolet curable resin. 2. An information recording medium having an information recording layer comprising a liquid crystal phase and a resin phase on an electrode layer, wherein the information recording layer comprises a liquid crystal, an ultraviolet-curable resin-forming material, and a fluorine-based surfactant. After applying a mixed solution dissolved in a solvent having a relative evaporation rate with respect to -n-butyl acetate smaller than 2 on the electrode layer, it is cured by irradiation with ultraviolet light, and its outer surface is formed on a skin layer made of only an ultraviolet-curable resin. An information recording medium, and an optical sensor having a photoconductive layer provided on an electrode layer are disposed in contact or non-contact with each other, and while applying a voltage between both electrodes of the information recording medium and the optical sensor, An information recording / reproducing method, wherein information is recorded by exposing and orienting a liquid crystal phase according to the information, and when reproducing the recorded information, the information is reproduced as visible information by transmitted light or reflected light. .