JPH10228670A - Information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent noise without requiring a high impressed voltage by incorporating a specific liquid crystal compd. into a mixture composed of cyanobiphenyl liquid crystals in a liquid crystal phase constituting an information recording layer. SOLUTION: At least one kind of 4-alkyl-4'-cyanobiphenyl liquid crystals or 4-alkoxy-4'-cyanobiphenyl liquid crystals are incorporated into the mixture described above and at least one kind of the liquid crystal compds. expressed by formula I, formula II, formula III and formula IV are incorporated therein. The amt. of the addition is recommended to be specified to a range of 0.5 to 20wt.% of the cyanobiphenyl based liquid crystals. The amts. of the addition of the formula I and formula II are preferably 1 to 6wt.% and the amts. of the addition are preferably 1 to 10wt.% in the case of the formulas III and the formula IV. In the formulas, R1 , R2 , R3 , R4 , R5 , R6 , R7 : alkyl, alkoxy group, A1 , B1 : bivalent groups consisting of phenyl pyrimidine, biphenyl, phenyl benzoic acid, phenyl cyclohexane, phenylbiphenyl carboxylic acid, biphenyl benzoic acid, etc., as skeleton, (n): 3 to 15, (m): 0 or 1.

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 having an information recording layer composed of a liquid crystal phase and a resin phase facing a photoconductive layer whose conductivity changes upon exposure to optical information.
In particular, the present invention relates to an information recording medium free from noise and capable of high-sensitivity recording.

[0002]

2. Description of the Related Art An optical sensor in which a photoconductive layer is laminated on an electrode and an information recording medium in which an information recording layer composed of a liquid crystal-polymer composite is laminated on the electrode are arranged on the optical axis so as to face each other.
Exposure while applying a voltage between both electrode layers, orienting the liquid crystal layer by an electric field formed by an optical sensor to record information, and reproducing the information recording as visible information with transmitted light or reflected light Playback method
First, JP-A-5-270140 and JP-A-5-165
005 and JP-A-6-130347.

[0003] The present applicant uses an ultraviolet curable resin as a resin for forming the information recording layer, thereby having a structure in which a liquid crystal phase and an ultraviolet curable resin phase are dispersed inside the information recording layer. Since the surface of the information recording layer is formed only of the resin layer, no liquid crystal seeping phenomenon occurs,
It has been found that information can be recorded without noise in information recording using an optical sensor, and that an electrode layer can be directly formed on a resin layer by sputtering, vapor deposition, or the like.

However, as a liquid crystal material for such an information recording medium, a smectic liquid crystal is preferably used from the viewpoint of recording properties. However, if the threshold voltage of the liquid crystal is high, it is difficult to apply a voltage when photographing. The voltage applied to the information recording medium increases, and a high voltage may be locally applied to each layer. Then, when a high voltage is locally applied, the portion where the transmittance of the information recording layer is higher than the transmittance corresponding to that obtained when the normal photographing is performed, which causes image noise.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an information recording medium which does not require a high applied voltage at the time of inputting information and therefore does not have noise.

[0006]

A first information recording medium according to the present invention has an information recording layer comprising a liquid crystal phase and a resin phase on an electrode layer, and the information recording layer is formed of a liquid crystal or an ultraviolet curable resin. In an information recording medium comprising a type resin and a fluorine-based surfactant, the liquid crystal phase contains at least one of a 4-alkyl-4'-cyanobiphenyl liquid crystal and a 4-alkoxy-4'-cyanobiphenyl liquid crystal, and Characterized by containing at least one of the liquid crystal compounds represented by the general formulas (1) to (4).

[0007]

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(Wherein A ₁ and B ₁ are divalent groups having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine. , R ₁ and R ₂ represent an alkyl group or an alkoxy group, and n represents an integer of 3 to 15.)

[0009]

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Wherein A ₂ and B ₂ are divalent groups having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine. , R ₃ and R ₄ each represent an alkyl group or an alkoxy group.)

[0011]

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(Wherein, R ₅ and R ₆ represent an alkyl group or an alkoxy group, and m represents an integer of 0 or 1).

[0013]

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(Wherein R ₇ represents an alkyl group or an alkoxy group.) The second information recording medium of the present invention is an information recording medium having an electrode layer, a photoconductive layer, an information recording layer, and an electrode layer sequentially provided. A medium,
In an information recording medium in which at least one of the electrode layers is transparent and the information recording layer is composed of a liquid crystal phase and a resin phase and is composed of a liquid crystal, an ultraviolet curable resin and a fluorine-based surfactant, Is 4-alkyl-4'-
Containing at least one of a cyanobiphenyl liquid crystal or a 4-alkoxy-4'-cyanobiphenyl liquid crystal,
It is characterized by containing at least one liquid crystal compound represented by the above general formulas (1) to (4).

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for schematically explaining a cross section of a first information recording medium according to the present invention, wherein 3 is an information recording medium, 11 is an information recording layer, and 13 is an electrode layer. , 15 are substrates.

The information recording layer 11 comprises a liquid crystal phase and a resin phase. At least one of 4-alkyl-4'-cyanobiphenyl liquid crystal and 4-alkoxy-4'-cyanobiphenyl liquid crystal in the liquid crystal phase constituting the information recording layer 11 (hereinafter, also referred to as cyanobiphenyl-based liquid crystal) has the following general formula: It is a compound represented by the formula (5).

[0017]

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(In the formula, R is an alkyl group having 2 to 18 carbon atoms or an alkoxy group having 2 to 18 carbon atoms.) The above-mentioned cyanobiphenyl-based liquid crystal can be prepared according to the intended use temperature or the like. The number of carbon atoms in the alkyl side chain or the alkoxy side chain is appropriately selected and used. In general, it is preferable to select a compound having a side chain having 2 to 18 carbon atoms, particularly 8 to 12 carbon atoms, to obtain a smectic material which is stable at around room temperature. It is preferable because a liquid crystal layer can be easily obtained.

As the cyanobiphenyl-based liquid crystal used in the present invention, only one compound may be used, but in order to obtain a liquid crystal composition having a low melting point, it is necessary to use a mixture of two or more compounds. preferable.

4-alkyl-4'-cyanobiphenyl has an excellent effect on lowering the melting point, and 4-alkoxy-4'-cyanobiphenyl has an excellent effect on stabilizing the smectic phase. When 4-alkyl-4'-cyanobiphenyl and 4-alkoxy-4'-cyanobiphenyl are used in combination with different kinds of compounds, a liquid crystal composition which is suitable for the purpose can be obtained relatively easily.
Particularly, 4-alkoxy- having 9 to 10 carbon atoms in the side chain.
Mainly a mixture of 1 to 4 parts by weight of 4-alkyl-4'-cyanobiphenyl having 9 to 10 carbon atoms in the side chain with respect to 1 part by weight of 4'-cyanobiphenyl, When a small amount of the cyanobiphenyl-based liquid crystal is mixed and used, the stability of the smectic phase is high and the melting point can be lowered, which is preferable. When the number of carbon atoms in the side chain is 1
One or more cyanobiphenyl-based liquid crystals lose the nematic phase in the liquid crystal phase series when the mixing amount is increased,
When used as an information recording medium, graininess (roughness) occurs. The amount at which this phenomenon occurs depends on the type and amount of the cyanobiphenyl-based liquid crystal, and therefore the mixing amount cannot be specified. However, a cyanobiphenyl-based liquid crystal having 11 or more carbon atoms in the side chain is a cyanobiphenyl-based liquid crystal. Is preferably 50% by weight or less based on the total amount of the mixture.

On the other hand, when a cyanobiphenyl-based liquid crystal having 8 or less carbon atoms in the side chain is mixed in a large amount, the temperature range of the nematic phase is widened, and the contrast is lowered when used as an information recording medium. The amount at which this phenomenon occurs also depends on the type and amount of the cyanobiphenyl-based liquid crystal, so that the amount of mixture cannot be specified unequivocally. Is preferably 50% by weight or less based on the total amount of the mixture. The driving voltage can be reduced by adding a small amount of cyanobiphenyl-based liquid crystal having 3 to 5 carbon atoms, for example, 1 to 10% by weight.

These cyanobiphenyl-based liquid crystals are generally commercially available and easily available. For example, 4-alkyl-4'-promobiphenyl or 4-alkoxy-4'-promobiphenyl can be used in combination with copper cyanide. By reacting, the corresponding 4-alkyl-4′-cyanobiphenyl or 4-alkoxy-4′-cyanobiphenyl can be synthesized.

In the present invention, the above-mentioned cyanobiphenyl-based liquid crystal or a mixture thereof is added to the above-mentioned general formula (1) to (4).
At least one of the compounds selected from the compounds represented by
Although seeds are added, the amount of each of these compounds is preferably in the range of 0.5 to 20% by weight.

The addition of the compounds of the above general formulas (1) and (2) imparts a strong torsional force to the smectic phase, disturbs the orientation of the liquid crystal, thereby improving the contrast and suppressing the roughness, and further reducing the driving voltage. Can be caused. The amount of this type of compound to be added may be appropriately selected in a total range of 0.1 to 20% by weight. If the amount is less than 0.1% by weight, the effect of improving the contrast and suppressing the roughness cannot be remarkably exhibited, and if the amount exceeds 20% by weight, the melting point tends to be undesirably high. These compounds are preferably added in an amount of 0.5 to 10% by weight, particularly 1 to 6% by weight, in order to obtain a particularly remarkable effect.

The groups A ₁ , A ₂ , B ₁ and B ₂ in the compounds of the general formulas (1) and (2) do not break the phase structure of the smectic phase of the cyanobiphenyl-based liquid crystal and have a phase with the biphenyl group. Any of the above-described groups having excellent solubility may be used, but a phenylpyrimidine group is particularly preferable because of its high compatibility.

The alkyl group and the alkoxy group of these compounds preferably have 1 to 15 carbon atoms, particularly preferably 5 to 12 carbon atoms, because of easy availability. Also,
N in the general formula (1) may be 3 to 15, and particularly, 6 to 12 is preferable because it is easily available.

Since the compounds of the general formulas (1) and (2) have an asymmetric carbon, there are optically active substances. In the present invention, a racemic form can be used, but an optically active substance is particularly preferable because it imparts a twist between the layers to weaken the force acting between the layers and disturbs the orientation to give a higher contrast.

More preferred compounds of the above general formula (1) include 2,9-dimethyldecyl-1,10-bis [4- (5-octylpyrimidin-2-yl) benzoate], 9-dimethyldecyl-1,10-bis (4-octyloxybenzoate), 2,9-
Dimethyldecyl-1,10-bis [4- (4-cyanophenyl) benzoate], 2,9-dimethyldecyl-1,10-bis [4- (4-octyloxyphenyl) benzoate], 2 , 9-dimethyldecyl-
1,10-bis [4- (4-octylphenylcarbonyloxy) benzoate], 2,9-dimethyldecyl-1,10-bis [4- (4-hexylcyclohexanyl) benzoate] and the like. Can be illustrated.

These compounds are obtained by ring-opening α, β, ψ, ω-diepoxyalkane with trimethylaluminum,
After converting to a primary alkanediol, diethyl azodicarboxylate triphenylphosphine [DEAD-P
(Ph) ₃ ] in the presence of a dehydrating agent. In this case, when an optically active substance (for example, S, S-form) is used as the diepoxide, the diol obtained above becomes an optically active substance (for example, R, R-form) in which the absolute configuration is inverted with respect to the diepoxide,
An optically active ester (for example, R, R-isomer) of the ester in a state where this is maintained is obtained.

Further, more preferred compounds of the general formula (2) are, for example, bis [4- (5-octylpyrimidin-2-yl) phenyl ester] 2-methylsuccinate and 2-methylsuccinic acid. Acid bis (4-octyloxyphenyl ester), 2-methylsuccinic acid bis [4
-(4-octyloxyphenyl) phenyl ester] and bis [4- (4-hexylcyclohexyl) phenyl ester] 2-methylsuccinate can be exemplified.

These compounds are obtained by dehydration condensation of 2-methylsuccinic acid and the corresponding phenol in the presence of a dehydrating agent such as dicyclohexylcarbodiimide in the presence of a catalyst such as N, N-dimethylaminopyridine. can get. In this case, when an optically active substance is used for the above-mentioned 2-methylsuccinic acid, the ester obtained above is an optically active substance in which the absolute configuration of 2-methylsuccinic acid is maintained.

On the other hand, the compounds of the above general formulas (3) and (4) have a function of lowering the viscosity of liquid crystal, that is, a so-called thinner, and their addition contributes to lowering of the driving voltage.

The addition amount of this type of compound is 0.5 to 30.
% By weight. If it is added in an amount of 0.5% by weight or less, it is difficult to sufficiently exhibit the effect of improving contrast and the effect of lowering the driving voltage. Is not preferred. These compounds are preferably added in an amount of 0.5 to 20% by weight, more preferably 1 to 10% by weight. The alkyl group and the alkoxy group of these compounds preferably have 1 to 15 carbon atoms, particularly preferably 1 to 10 carbon atoms, because of easy availability.

More preferred compounds of the general formula (3) include 4- (trans-4-bentylcyclohexyl) -4'-methylbiphenyl and 4- (trans-4-propylcyclohexyl)- 4'-ethylbiphenyl, 4- (trans-4-butylcyclohexyl) -4'-ethylbiphenyl, 4- (trans-4-
Pentylcyclohexyl) -4′-ethylbiphenyl,
4- (trans-4-hexylcyclohexyl) -4 ′
-Ethylbiphenyl, 4- (trans-4-pentylcyclohexyl) -4'-propylbiphenyl, 4- (trans-4-pentylcyclohexyl) -4'-pentylbiphenyl, 4- (trans-4-pentylcyclohexyl) -4 '-Methoxybiphenyl, 4- (trans-4-butylcyclohexyl) -4'-methoxybiphenyl, 4- (trans-4-propylcyclohexyl)
Examples thereof include -4'-methoxybiphenyl, 4- (trans-4-pentylcyclohexyl) -4'-propyloxymethylbiphenyl, and the like.

These compounds are prepared by reacting 4- (4-alkylcyclohexyl) -4'-biphenyl with alkyl acid chloride in the presence of anhydrous aluminum chloride.
(4-alkylcyclohexyl) -4′-alkanoylbiphenyl, which is reduced with hydrogen in the presence of palladium carbon, or 4- (4-alkylcyclohexyl) -4′-formylbiphenyl is treated with sodium borohydride Reducing to 4- (4-alkylcyclohexyl) -4'-hydroxymethylbiphenyl, reacting with thionyl chloride to form 4- (4-alkylcyclohexyl) -4'-chloromethylbiphenyl, and reacting with sodium alkoxide Is obtained by

More preferred compounds of the general formula (4) are, specifically, 4-hexylbenzoic acid-4
-Fluorophenyl ester, 4-octylbenzoic acid-
Examples thereof include 4-fluorophenyl ester and 4-hexyloxybenzoic acid-4-fluorophenyl ester. These compounds can be obtained by dehydrating and condensing 4-alkyl or 4-alkoxybenzoic acid and 4-fluorophenol in the presence of a catalyst such as N, N-dimethylaminopyridine in the presence of dicyclohexylcarbodiimide or the like.

The compounds of the above general formulas (1) to (4) may be added alone, but provide higher contrast,
In order to achieve good granularity and low driving voltage and obtain good images, the compound of the general formula (3) and / or (4) is added to the compound of the general formula (1) and / or (2). It is preferable to use them in combination. The amount of addition in this case may be appropriately selected within the above-mentioned range. In the liquid crystal composition of the present invention, in addition to these compounds, a liquid crystal compound such as 4-alkyl-4 ″ -cyanoterphenyl or a non-liquid crystal compound in a range that does not damage the liquid crystal layer may be added. it can.

Next, as a material for forming the resin phase, an ultraviolet curable resin which is compatible with the liquid crystal at room temperature or by heating in a monomer or oligomer state,
Alternatively, a compound having compatibility with a solvent common to a liquid crystal material at room temperature or by heating in a state of a monomer or an oligomer may be 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 , Polyfunctional monomers such as polypropylene glycol diacrylate, isocyanuric acid (ethylene oxide-modified) triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetraacrylate, neopentyl glycol diacrylate, hexanediol diacrylate, and the like. Ester oligomers, further nonylphenol-modified acrylates, N-vinyl-2-pyrrolidone, 2-
Monofunctional monomers or oligomers such as hydroxy-3-phenoxypropyl acrylate are exemplified.

As the UV-curable resin, general formulas (6) and (7)

[0041]

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The following can also be used.

Next, as a common solvent for the liquid crystal and the ultraviolet-curable resin monomer, a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate is used. It must be a common solvent for each of the fluorine-based surfactants. "A solvent having a relative evaporation rate to n-butyl acetate of less than 2"
For example, Yuji Harazaki, "Easy-to-understand coating technology" 2
17 to 221, published by Riko Publishing Co., and the evaporation rate is the volatility at a certain temperature, R is smaller than 2.

The solvent that can be used in the present invention includes:
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 (“Darocur 1173” manufactured by Ciba-Geigy), 1-
Hydroxycyclohexyl phenyl ketone (“IRGACURE 184” manufactured by Ciba-Geigy), 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one (“Darocur 111” manufactured by Ciba-Geigy)
6 "), benzyldimethyl ketal (" Irgacure 651 "manufactured by Ciba-Geigy), 2-methyl-1- [4-
(Methylthio) phenyl] -2-morpholinopropanone-1 (“Irgacure 907” manufactured by Ciba-Geigy),
A mixture of 2,4-diethylthioxanthone (Nippon Kayaku Co., Ltd. “Kayacure DETX”) and ethyl p-dimethylaminobenzoate (Nippon Kayaku Co., Ltd. “Kayacure EPA”),
Isopropyl thioxanthone (a mixture of "Kuntacure ITX" manufactured by Ward Brekinsop and ethyl p-dimethylaminobenzoate, etc., and the like.
-Hydroxy-2-methyl-1-phenylpropane-1
-One is particularly preferred in terms of compatibility.

In addition to the wettability of the information recording layer with respect to the electrode layer, a fluorine-based surfactant is added for the purpose of forming a skin layer made of only resin on the surface of the information recording 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.

The content ratio of the liquid crystal in the information recording layer is 1
It is 0% to 90% by weight, preferably 40% to 80% by weight. When the content of the liquid crystal is less than 10% by weight, the light transmittance is low even when the liquid crystal phase is oriented by information recording, and when the content exceeds 90% by weight, phenomena such as oozing of the liquid crystal occur and image unevenness occurs. Not preferred. Further, according to the present invention, the outer surface of the information recording layer can be a skin layer composed of a resin layer. As a result, the content of the liquid crystal can be increased to 40% to 80% by weight of the liquid crystal, and high sensitivity,
A high-contrast information recording medium can be obtained.

Further, the information recording layer is opaque due to light scattering when no electric field is applied by setting the light refractive index of the aligned liquid crystal phase and the light refractive index of the resin phase to be substantially the same. The liquid crystal phase is oriented so that 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.

Next, as a method of forming the information recording layer, a liquid crystal, an ultraviolet curable resin monomer, a photopolymerization initiator, and a surfactant are mixed with a solvent having a relative evaporation rate of less than 2 with respect to n-butyl acetate. , Solids concentration of 10-60% by weight
To be a mixed solution. Solvent dilution is 1 to 500 cps
(20 ° C), preferably 10 to 200 cps (20 ° C)
It is. 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 melted at a temperature higher than the temperature at which the liquid crystal maintains an isotropic phase, preferably within a temperature range of the isotropic phase transition point + 10 ° C. , Blade coater,
Alternatively, a uniform coating is applied by a coating method such as a roll coater.

Next, the dried coating layer is irradiated with ultraviolet rays using a UV lamp to cure the coating layer. When the coating layer is irradiated with ultraviolet rays, infrared rays are shielded and the coating layer is irradiated with ultraviolet rays.
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 of 1% or more at a wavelength of m to 400 nm at an energy of 0.1 mJ / cm ² or more. .

When the information recording layer is formed as described above,
On the surface of the information recording layer, 0.01% to 3% of the thickness of the information recording layer
A skin layer having a thickness of 0% is formed, and the inside of the information recording layer has a primary particle size of 0.03 μm to 0.2 μm.
A structure in which resin particles of 3 μm are filled and a liquid crystal phase is communicated therebetween can be obtained. When the ultraviolet-curable resin monomers represented by the above general formulas (6) and (7) are used, the surface skin layer can have excellent durability. 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.

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 is a problem that the contrast cannot be obtained. Also,
If the phase separation is incomplete, the information recording layer itself will have low resistance, and when recording information by the action of an electric field by electrostatic information using an optical sensor, no voltage is applied to the liquid crystal phase in the information recording layer effectively. In addition, there is a problem that the liquid crystal drive becomes slow and the sensitivity is lowered. Also, if the phase separation is incomplete, when the UV-curable resin-forming material is irradiated by a UV lamp containing infrared rays, unnecessary heating causes non-uniform shrinkage. There is a serious problem that the recording layer cannot be used.

The average thickness of the information recording layer is 1 μm to 30 μm.
m. If the film thickness is too thick, the operating voltage will increase,
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 make the contrast ratio excellent with the sensitivity, the film thickness is preferably 3 μm to 20 μm, more preferably 5 μm to 20 μm.
The thickness is preferably from 10 μm to 10 μm. Thus, the operating voltage can be reduced while maintaining high contrast.

The thickness of the skin layer in the information recording layer can be in the range of 0.01% to 50% of the thickness of the information recording layer. Even if the information is recorded, noise occurs. Therefore, it is preferable that the thickness of the skin layer is 0.01% to 30% of the thickness of the information recording layer.
The thickness of the skin layer can be appropriately adjusted by the amount of ultraviolet irradiation, the addition of a fluorine-based surfactant, and the like, although the detailed reason is unknown.

Further, in the information recording medium of the present invention,
It is necessary that the thickness of the information recording layer be accurately and uniformly applied. However, by forming the information recording layer by the above method, the uniformity of the film thickness can be improved when the film thickness is 5 μm to 10 μm. Has a surface roughness Ra of 200 ° or less, has no contrast unevenness, and does not cause a shading phenomenon even during information recording.

In general, in the case of this type of polymer-dispersed liquid crystal, it is considered that the resolution depends more on the domain size of the liquid crystal than on the film thickness. In the case of a layer where the content of liquid crystal is large, such as a layer, and the resin forms a phase in the form of particles, the domain size of the liquid crystal needs to be taken into account much like a polymer-dispersed liquid crystal with a low content of ordinary liquid crystal. Without high sensitivity
In addition, an information recording medium having a high contrast ratio can be easily provided.

Further, by forming a skin layer on the surface of the information recording layer of the present invention, it is possible to prevent the liquid crystal from bleeding out. A thermoplastic resin film, a thermosetting resin film,
An ionizing radiation curable resin film such as an ultraviolet curable resin may be laminated by a coating method. As a material for forming these resin layers, particularly preferably, polyethylene terephthalate, polyethylene, polypropylene, ultraviolet ray and electron beam curable resin and the like can be mentioned, and even when formed into a thin film, a hard coat layer having a high surface hardness can be obtained. It is possible to improve the durability of the information recording medium. The thickness of the resin layer is 0.1
The thickness is preferably from 20 μm to 20 μm, more preferably from 0.1 μm to 5 μm. However, when the thickness of the resin layer is large, the operating voltage applied to the liquid crystal phase during information recording is low. Therefore, when an optical sensor described later is used as the information recording mode, the applied voltage is increased. There is a need to.
By laminating such a resin layer, the bleeding phenomenon of liquid crystal from the surface of the information recording layer can be further prevented, and the hardness of the surface of the information recording layer can be increased. By changing the film thickness, the voltage applied to the information recording layer can be controlled, so that the recordable exposure range can be controlled.

The electrode layer 13 is required to be transparent when the information recorded on the information recording layer is read by transmitted light, and has a specific resistance of 10 ⁶ Ω · cm or less. Film, inorganic metal oxide conductive film such as indium tin oxide,
Organic conductive films such as quaternary ammonium salts. The electrode layer is formed by a method such as vapor deposition, sputtering, CVD, coating, plating, dipping, and electrolytic polymerization. Further, the film thickness needs to be changed depending on the electrical characteristics of the material constituting the electrode and the applied voltage at the time of information recording. For example, the thickness of the ITO film is about 100 to 3000 °, and the entire surface between the information recording layer and Alternatively, it is formed according to the formation pattern of the information recording layer.

When information recorded on the information recording layer is read by reflected light, the electrode layer may be made light-reflective, or a light reflection layer may be laminated on the transparent electrode layer. In order to make the electrode layer light-reflective, a metal electrode such as aluminum may be used. The light reflecting layer may be, for example, a dielectric mirror layer, and may be provided on at least one of the electrode layers or on both surfaces.

The substrate 15 may be transparent or opaque, depending on whether information is read with transmitted light or reflected light. The information recording medium can have a shape such as a card, a film, a tape, a disk, etc., but the support supports the information recording medium in a strong manner, and when the information recording layer has a supporting property, No need to provide. The material and thickness of the support are not particularly limited, for example, a flexible plastic film or glass,
Rigid bodies such as plastic sheets and cards are 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.

When information is reproduced with transmitted light, whether a layer having an anti-reflection effect is laminated on the substrate as necessary or the transparent substrate is adjusted to a film thickness capable of exhibiting the anti-reflection effect. It is preferable to provide an antireflection property by combining the two.

Next, a method for recording information on the first information recording medium of the present invention will be described. The information is recorded using a method such as an optical sensor, heat, laser, or corona charging. Preferably, the information is recorded using an optical sensor.

An optical sensor is one in which an electrode layer and a photoconductive layer are laminated on a transparent substrate. The photoconductive layer is a single-layer system 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.

The single-layer photoconductive layer is formed of an inorganic photoconductive substance or an organic photoconductive substance. Se, Se—Te, ZnO, TiO ₂ , S
i, CdS, etc .;
5-30 μm alone or in a mixed system on the electrode layer by a method or the like
m, preferably 20 to 30 μm. Further, the above-mentioned inorganic photoconductor as fine particles, an organic insulating resin, for example, a silicone resin, a polyester resin, a polycarbonate resin, a styrene-butadiene resin, a styrene resin, a polyvinyl acetal resin may be dispersed to form a photoconductive layer, In this case, the photoconductive fine particles may be dispersed in a proportion of 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 1 part by weight of the resin.

The organic photoconductive substance includes a polymer photoconductive substance and a dispersion of a low molecular weight photoconductive substance in an insulating binder. Examples of the polymer photoconductive substance include polyvinyl carbazole (PVK), and poly-N-ethylenically unsaturated group substitution containing an ethylenically unsaturated group such as an allyl group or an acryloxyalkyl group instead of a vinyl group in PVK. There are also carbazoles, poly-N-ethylenically unsaturated group-substituted phenothiazines such as poly-N-acrylphenothiazine, poly-N- (β-acryloxy) phenothiazine, polyvinylpyrene and the like. Among them, poly
N-ethylenically unsaturated group-substituted carbazoles, particularly polyvinyl carbazole, are preferably used. Examples of the low molecular weight photoconductive substance include oxadiazoles substituted with an alkylaminophenyl group, a triphenylmethane derivative, a hydrazone derivative, a butadiene derivative, and a stilbene derivative. In an amount of 0.1 to 5 parts by weight, preferably 0.1 to 1 part by weight of an electrically insulating resin such as a silicone resin, a polyester resin, a polycarbonate resin, a styrene-butadiene copolymer resin, a styrene resin, and a polyvinyl acetal resin. To form a film-forming organic photoconductive substance. The film thickness of these organic photoconductive materials after drying is 5 to 30.
μm, preferably 10 to 30 μm.

The organic photoconductive layer may be added, if necessary, with a sustained conductivity imparting agent described in Japanese Patent Application No. 4-287983. The above-mentioned organic photoconductive layer itself has sustained conductivity, and this persistent conductivity imparting agent is added for the purpose of enhancing the sustained conductivity in the above-mentioned organic photoconductive layer. The sustaining conductivity imparting agent is 0.001 to 1 part by weight based on 1 part by weight of the organic photoconductive substance,
Preferably, it is added in a ratio of 0.001 to 0.1 parts by weight. When the amount of the sustained conductivity-imparting agent exceeds 1 part by weight,
This is not preferable because the amplifying function of the photoconductive layer is significantly reduced. Also, some sustained conductivity-imparting substances do not have spectral sensitivity in visible light, and when utilizing light information in the visible light region, an electron-accepting material is used to increase sensitivity in the visible light region. A dye or the like can be further added. Examples of the electron accepting substance include nitro-substituted benzene, cyano-substituted benzene, halogen-substituted benzene, quinones, and trinitrofluorenone. Examples of the sensitizing dye include a triphenylmethane dye, a pyrylium salt dye, and a xanthene dye. Electron accepting substances, sensitizing dyes, etc.
0.001 to 1 part by weight, preferably 0.01 to 1 part by weight, is added to 1 part by weight of the organic photoconductive substance. At the same time, if the optical information is in the infrared region, it is advisable to add the same amount of a pigment such as phthalocyanine, a pyrrole-based dye, or a cyanine-based dye, and conversely, there is information light in the ultraviolet region or in a wavelength region below it. In this case, the purpose is achieved by adding the same amount of each wavelength absorbing substance.

Next, the laminated photoconductive layer is formed by sequentially laminating a charge generation layer and a charge transport layer on an electrode, and includes an inorganic material type photoconductive layer and an organic material type photoconductive layer. The charge generation layer in the inorganic system is formed by depositing Se-Te, Si doped with sulfur, oxygen, or the like on the electrode to a thickness of 0.05 μm to 1 μm by an evaporation method, a sputtering method, a CVD method, or the like. Next, on this charge generation layer, Se, As
_It is preferable to form a layer of 10 μm to 50 μm in thickness in the same manner, for example, by doping ₂ Se ₃ , Si, Si or the like doped with methane.

Next, the charge generation layer in the organic system is composed of a charge generation material and a binder.
Fluorenone azo pigments, monoazo pigments, bisazo pigments, pyrrole pigments, azulenium salt pigments, phthalocyanine pigments, polycyclic aromatic pigments, pyrylium salt pigments, triazo pigments, squarylium salt pigments, perylene pigments And anthantrone pigments, cyanine pigments, polycyclic quinone pigments, imidazole pigments and the like, and specific examples thereof include charge generation substances described in Japanese Patent Application No. 4-287983.

Examples of the binder include a silicone resin, a styrene-butadiene copolymer resin, an epoxy resin, an acrylic resin, a saturated or unsaturated polyester resin, a PMMA resin, a vinyl chloride resin, a vinyl acetate resin, and a vinyl chloride-vinyl acetate mixed resin. And formed by dispersing the charge generating material in a binder. The charge generator is preferably a fluorenone azo pigment or a bisazo pigment, and the binder is preferably a polyester resin or a vinyl chloride-vinyl acetate mixed resin. The mixing ratio of the charge generating agent and the binder is preferably 0.1 to 10 parts by weight, and more preferably 0.1 to 1 part by weight, per 1 part by weight of the charge generating agent. The charge generation layer has a thickness of 0.01 to 1 μm after drying, preferably 0.1 to 1 μm.
It is good to be 0.3 μm.

The charge transport layer comprises a charge transport substance and a binder. The charge transport substance is a substance having a good charge transport property of the charge generated by the charge generation substance, for example, a hydrazone type,
There are pyrazoline type, PVK type carbazole type, oxazole type, triazole type, aromatic amine type, amine type, triphenylmethane type, butadiene type, stilbene type, polycyclic aromatic compound type, etc. It is necessary to. Preferred are butadiene-based and stilbene-based charge transport agents.
And the charge transport materials described in JP-A-289833.

As the binder, those similar to the binders in the above-described charge generation layer can be used, and preferred are polyvinyl acetal resin, styrene resin, and styrene-butadiene copolymer resin. The binder is
It is desirable to use 0.1 to 10 parts by weight, preferably 0.1 to 1 part by weight, per 1 part by weight of the charge transporting agent. The thickness of the charge transport layer after drying is 1 to 50 μm, and preferably 10 to 30 μm.

Examples of combinations of these charge generating substances and charge transporting substances include a combination of a fluorenone azo pigment (charge generating substance) and a stilbene type charge transporting agent, a bisazo type pigment (charge generating substance) and a butadiene type, and a hydrazone type. And the like are good.

The sustaining conductivity-imparting agent and the electron-accepting substance described in the section of the single-layer photoconductive layer are added to the charge generating layer and the charge transporting layer in the stacked photoconductive layer at the same ratio. However, it is preferably added to the charge generation layer.

When the single-layer photoconductive layer and the laminated photoconductive layer are organic photoconductive layers, dichloroethane, 1,1,2-trichloroethane, monochlorobenzene, tetrahydrofuran, cyclohexane, dioxane, and dioxane are used as solvents. , 2,3-trichloropropane, ethyl cellosolve, 1,1,1, -trichloroethane, methyl ethyl ketone, chloroform, toluene, etc., and the coating solution may be used. The coating method includes a blade coating method, a dipping method, and a spinner. Coating methods and the like can be mentioned.

The photoconductive layer may contain an electron-accepting substance, a sensitizing dye, an antioxidant, an ultraviolet absorber, a light stabilizer and the like. The electron-accepting substance or the sensitizing dye has a base current regulating action, a base current stabilizing action, or a photo-induced current amplifying action. Examples of the electron-accepting substance include compounds listed as nitro-substituted benzenes, amino-substituted benzenes, halogen-substituted benzenes, substituted naphthalenes, benzoquinones, nitro-substituted fluorenones, chloranyls, and charge-transporting substances. Examples of the sensitizing dye include a triphenylmethane dye, a pyrylium salt dye, a xanthene dye, and a leuco dye. The electron-accepting substance and the sensitizing dye are used in an amount of 0.0
It is added in an amount of from 0.01 to 10 parts by weight, preferably from 0.01 to 1 part by weight. When the amount is less than 0.001 part by weight, no action is exhibited. When the amount is more than 10 parts by weight, the image quality is adversely affected.

Examples of the antioxidant include a phenolic antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant, and examples of the ultraviolet absorber include a salicylic acid-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, and a benzotriazole-based ultraviolet absorber. Examples of the light stabilizer include a cyanoacrylate-based ultraviolet absorber and a light stabilizer. Examples of the light stabilizer include an ultraviolet stabilizer and a hindered amine-based light stabilizer.

The antioxidant, the ultraviolet absorber and the light stabilizer may be used alone or in combination of two or more, in an amount of 0.001 to 10 parts by weight, preferably 0.01 to 1 part by weight, per 1 part by weight of the photoconductive substance. Parts are added. 0.001
If the amount is less than 10 parts by weight, the effect of adding these substances cannot be obtained. If the amount is more than 10 parts by weight, the image quality is adversely affected. In the case of a stacked optical sensor, it can be added to the charge generation layer and the charge transport layer at the same ratio. Preferably, these substances are added to the charge generation layer.

A photo-induced current amplification layer may be provided between the electrode 13 and the photoconductive layer 14. The photo-induced current amplification layer is
(1) The function of amplifying the current generated by the light induction in the optical sensor and (2) the charge carrier injection property from the electrode to the photoconductive layer is controlled to adjust the voltage substantially applied to the information recording medium. And (3) uniformity of charge carrier injection from the electrode to the photoconductive layer to reduce noise and unevenness of information recorded on the information recording medium. The first effect is effective in improving the recording sensitivity of the optical sensor, the second effect is effective in controlling the image density of the recorded image, and the third effect is effective in improving the image quality of the recorded image. It is effective.

The photo-induced current amplification layer may be made of, for example, a silicone resin, a polycarbonate resin, a vinyl formal resin, a vinyl acetal resin, a vinyl butyral resin, a styrene resin, a styrene-butadiene copolymer resin, an epoxy resin, an acrylic resin, a saturated or non-saturated resin. It is composed of a saturated polyester resin, a methacrylic resin, a vinyl chloride resin, a vinyl acetate resin, a vinyl chloride-vinyl acetate copolymer resin, or a combination of plural resins. Furthermore, soluble polyamide, phenolic resin, polyurethane, polyurea, casein, polypeptide, polyvinyl alcohol, polyvinylpyrrolidone, maleic anhydride polymer, quaternary ammonium salt-containing polymer, cellulose compound, etc., alone or in combination of plural ones Can also be used. Particularly, a vinyl formal resin, a vinyl acetal resin, and a vinyl butyral resin are preferable.

The thickness of the photo-induced current amplification layer is 0.005 to
The thickness is 5 μm, preferably 0.05 to 0.5 μm, and can be applied by a method such as dip coating, roll coating, and spin coating. 0.0
When the thickness is less than 05 μm, the effect of reducing image noise is lost, and when the thickness is more than 5 μm, injection of charge carriers from the electrode to the charge generation layer is hindered.

The photo-induced current amplifying layer may include various electron-accepting substances, photoconductive substances, inorganic salts,
Organic salts are added, and each additive can be used alone or in combination. Examples of the electron accepting substance include substituted benzenes, substituted naphthalenes, substituted and unsubstituted benzoquinones, substituted and unsubstituted naphthoquinones, substituted and unsubstituted anthraquinones, substituted fluorenones, chloranyls, and substituted quinodimethanes. be able to.

As the photoconductive substance, the above-mentioned inorganic and organic photoconductive substances in the single-layer system and the charge-generating substances in the multilayer system can be used. As the charge-generating substance, pyrylium dyes, thiapyrylium dyes,
Azurenium dyes, cyanine dyes, chaotic dyes such as azurenium dyes, squarylium salt dyes, polycyclic quinone pigments such as phthalocyanine pigments, perylene pigments, pyranthrone pigments, indigo pigments, quinacridone pigments, pyrrole Dyes and pigments, such as a system pigment and an azo pigment, can be used alone or in combination.

These additives are used in an amount of 0.001 to 10 parts by weight, preferably 0.1 to 10 parts by weight, based on 1 part by weight of the binder resin.
And an additive may be used alone or in combination of two or more. Particularly, an electron accepting compound such as a combination of a substituted benzoquinone and an azo pigment may be used. It is preferable to use a conductive pigment in combination, since a large amplification effect can be obtained.

Next, a description will be given of the photo-induced current amplifying action in the optical sensor section including the electrode and the photoconductive layer. The photo-induced current is the current value of the light-irradiated part minus the base current value, which is the current flowing in the part not irradiated with light. Say.

In the photosensor of the present invention, not all of the photoinduced charge carriers generated by the irradiation of information light move in the layer width direction of the photoconductive layer when the voltage is applied. Is trapped in a trap site existing in the photoconductive layer or at the interface between the electrode and the photoconductive layer, and the trapped charges are accumulated with time and are generated by exposure when a voltage is applied. In addition to the photo-induced current, the injected current from the electrode induced by the trapped charges flows, and the apparent photo-induced current is amplified over time. When the exposure is terminated while maintaining the voltage applied, the photocarriers generated by the exposure are immediately attenuated and disappear, but the decay of the trapped charge is slow, so that the induced charge is induced by the trapped charge. It is presumed that a sufficient amount of injection current flows from the electrode while attenuating. This photo-induced current is an effect of current amplification triggered by light in the optical sensor of the present invention,
Since a current equal to or more than a photo-induced current caused by incident light expected in a normal photoconductor flows, it is possible to effectively provide optical information to an information recording medium.

The photosensor portion comprising the electrode and the photoconductive layer according to the present invention is semiconductive as a whole element including the electrode, and has a specific resistance in darkness of 10 ⁹ to 1 depending on the current density flowing.
It is preferably 0 ¹³ Ω · cm. In particular, the specific resistance is 1
The amplification effect is remarkable in the range of 0 ¹⁰ to 10 ¹¹ Ω · cm. An optical sensor having a specific resistance of more than 10 ¹³ Ω · cm does not exhibit an amplifying effect as in the optical sensor of the present invention in an electric field intensity range of 10 ⁵ to 10 ⁶ V / cm. In the case of an optical sensor having a specific resistance of less than 10 ⁹ Ω · cm, a very large amount of current flows, and noise due to the current is likely to occur, which is not preferable. On the other hand, a photosensitive element used for general electrophotography has a dark resistivity of 10 ¹⁴ Ω · cm to 10 ¹⁶ Ω · cm.
Are used, and the optical sensor of the present invention cannot achieve its purpose even when used for general electrophotography,
Further, a photosensitive element having a photoconductive layer having a large dark resistivity for general electrophotography cannot be used for the purpose of the present invention.

The specific resistance ρ (Ω · cm) of the optical sensor is represented by the following equation: the current density J (A / cm ² );
Assuming that the electrode area S and the applied electric field strength E (V / cm), the relational expression of ρ = (E · d / J · S) × (S / d) = E / J holds. Can be obtained from

When the information recording layer of the information recording medium is a polymer-dispersed liquid crystal, it is necessary to set the sensitivity of the optical sensor in the operating voltage range of the liquid crystal. That is, the contrast voltage, which is the difference between the potential (bright potential) applied to the information recording medium in the exposed part and the potential (dark potential) applied to the information recording medium in the unexposed part, is the operating voltage of the liquid crystal in the information recording medium. It is necessary to take a certain size in the area. Therefore, for example, the dark potential applied to the liquid crystal layer in the unexposed portion of the optical sensor needs to be set to about the operation start potential of the liquid crystal. Therefore, the resistivity of the information recording medium at room temperature is 10 ¹⁰ to 10 ¹³ Ω ·
cm, and a conductivity is required to generate a base current of 10 ^-4 to 10 ^-7 A / cm ^{2 when} an electric field of 10 ⁵ to 10 ⁶ V / cm is applied to the optical sensor. The range is preferably 10 ^-5 to 10 ^-6 A / cm ² . In an optical sensor having a base current of less than 10 ^-7 A / cm ² , the liquid crystal layer is not aligned even in the exposed state, and in an optical sensor having a base current of 10 ^-4 A / cm ² or more, the voltage is simultaneously applied even in the unexposed state. A large amount of current flows, the liquid crystal is oriented, and even when exposed, no difference in transmittance is obtained between the unexposed portion and the unexposed portion. Since the operating voltage and the range vary depending on the liquid crystal, it is necessary to consider the voltage distribution in the information recording medium when setting the applied voltage and the voltage application time.

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, 13 'are electrode layers, 14 is a photoconductive layer, 11 is an information recording layer, 15 is a substrate, 19 is a spacer, 21 is a light source, 22
Denotes a shutter having a driving mechanism, 23 denotes a pulse generator (power supply), and 24 denotes a dark box.

First, a voltage is applied between the electrodes 13 and 13 'by a power supply. When recording on this information recording medium, the information recording medium is heated, for example, by resistance heating (not shown) embedded in its support, and the liquid crystal is heated to a temperature that indicates a liquid crystal phase. Can be 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 at 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 the recording according to the information light pattern is performed. In the figure, the photoconductor side is a positive electrode and the information recording medium side is a negative electrode. However, it goes without saying that 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 first 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.

Further, as a recording method using a laser,
The light source is an argon laser (514.488n)
m), a helium-neon laser (633 nm), a 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 images 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 laser light. 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 read visually, but can also be read by enlarging it with a projector, using laser scanning or CC.
Information can be read with high accuracy by reading using D, and scattered light can be prevented by using a schlieren optical system as needed. Further, as described above, by making the electrode layer itself light-reflective or by laminating a light-reflective layer on the electrode layer, reading can be performed by reflected light.

Next, a second information recording medium of the present invention will be described. The second information recording medium has a photoconductive layer incorporated in the first information recording medium, and does not require an optical sensor or the like when recording information, and can record information by itself. FIG. 4 (a) is a diagram for schematically explaining the cross section, in which 3 is an information recording medium, 11 is an information recording layer, 13 and 13 'are electrode layers, 14 is a photoconductive layer, and 15 is a photoconductive layer.
Is a substrate.

Photoconductive layer 14 laminated on electrode 13 '
Is the same as the photoconductive layer in the above-described optical sensor. On this photoconductive layer, the information recording layer 11 described in the section of the first information recording medium is provided with the first information recording medium. It is laminated in the same manner.

Further, according to the first method for forming the information recording layer, the liquid crystal can be prevented from seeping out from the surface of the information recording layer.
3 can be formed by sputtering.
The information recording layer can have high insulation properties and can be an information recording layer free of noise when recording information.

For the electrode layers 13 and 13 ', the same material and the same forming method as those of the above-mentioned electrode layer in the first information recording medium can be adopted. When reading with reflected light, either one of the electrode layers may be made light-reflective, or a light-reflecting layer such as a dielectric mirror layer may be laminated on one of the electrode layers. Further, a substrate may be laminated on the electrode 13 on the information recording layer.

In the second information recording medium, an intermediate layer 12 may be provided between the photoconductive layer 14 and the information recording layer 11, as shown in FIG. When the photoconductive layer is an organic photosensitive layer formed using a solvent, the intermediate layer 12 may elute liquid crystal in the information recording layer depending on the solvent, When forming on the layer, the solvent for forming the information recording layer elutes the photoconductive material to cause image unevenness, which is provided to prevent this.

As such an intermediate layer, inorganic materials such as SiO ₂ , TiO ₂ , CeO ₂ , Al ₂ O ₃ , GeO ₂ , Si ₃ N ₄ , AlN,
It is preferable to use TiN, MgF ₂ , ZnS, or the like, and to form a layer by vapor deposition, sputtering, chemical vapor deposition (CVD), or the like.

An aqueous solution such as polyvinyl alcohol, water-based polyurethane, or water glass is used as a water-soluble resin having low compatibility with an organic solvent, and is laminated by spin coating, blade coating, roll coating, or the like. Good. Further, a fluorine resin which can be applied may be used. In this case, the resin may be dissolved in a fluorine-based solvent and applied by a spin coating method, or may be laminated by a blade coating method, a roll coating method or the like. As the fluorine resin which can be applied, the fluorine resin described in Japanese Patent Application No. Hei 4-24722 can be suitably used.

In the case of an organic material formed in a vacuum system, there is no fear that the photoconductive layer is dissolved when the film is formed. Among these materials, polyethylene, polypropylene, poly (monochlorotrifluoroethylene), polytetrafluoroethylene, etc. can be used as a material to be formed by a vapor deposition method.
In addition, as a material for forming a film by the CVD method, polyparaxylene or the like specifically described in Japanese Patent Application No. 4-24722 can be used.

Among the above-mentioned various materials, it is particularly preferable to use polyvinyl alcohol, and when a material having a saponification degree of 97% or more and a polymerization degree of 1500 or more is used, the formation of the information recording layer is improved. I can do it.

In forming the intermediate layer, it is necessary that the intermediate layer does not have compatibility with any of the organic photoconductive layer forming material and the information recording layer forming material. Since diffusion occurs and the resolution deteriorates, an insulating property of 10 ⁷ Ωcm or more is required. Also,
The thickness of the intermediate layer is preferably 2 μm or less, and more preferably 0.01 μm to 1.5 μm, because it reduces the distribution voltage applied to the liquid crystal layer or deteriorates the resolution. If the thickness is too small, not only image noise due to the interaction with time will occur, but also a problem of penetration due to defects such as pinholes at the time of lamination coating will occur. Since the permeability varies depending on the solid content ratio of the material to be laminated and applied, the type of solvent, and the viscosity, the thickness of the material to be laminated and coated may be appropriately set. The intermediate layer is required to have transparency, and in consideration of the voltage distribution applied to each layer, a material having a high dielectric constant as well as a thin film is preferable. When there is no interaction such as liquid crystal seepage with the information recording layer such as when the photoconductive layer is formed of an inorganic material, it is not necessary to provide an intermediate layer.

The method of recording information on the second information recording medium will be described with reference to FIG. First, electrode 1
When the information light 18 enters while applying a voltage between 3 and 13 ', the photocarriers generated in the photoconductive layer 14 at the portion where the light enters are moved by the electric field formed by both electrodes,
When the voltage is redistributed, the liquid crystal phase in the information recording layer is oriented, and recording according to the pattern of the information light 18 is performed. The voltage may be applied for a predetermined time while the information light 18 is being incident.

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 in the information recording medium is appropriately set, and the voltage distribution applied to the information recording layer is determined by the operation of the liquid crystal. It is preferable to set the voltage range.

In this information recording method, planar analog recording is possible, and recording at the liquid crystal particle level is obtained, so that high resolution is obtained. Further, the exposure pattern is visualized and maintained by the orientation of the liquid crystal phase. Is done. As the information input method, the same method as the method using a camera or the method using a laser described in the section of the first information recording medium can be used. Further, a recording method using a laser can be similarly performed. Further, the spectral characteristics of the photoconductive layer do not need to be panchromatic, as long as they have sensitivity to the wavelength of the laser light source.

Information recorded on the second information recording medium is as follows:
In the case of reading by transmitted light, the reproduction is performed by the transmitted light from the information recording layer side in the same manner as in the case of the first information recording medium shown in FIG. 3, and the same is applied in the case of reading by the reflected light.

Next, as shown in FIG. 4C, the second information recording medium of the present invention comprises an insulating light reflecting layer 12 between the photoconductive layer and the information recording layer in the second information recording medium. ', A transparent insulating layer 12 "may be provided.
Recorded information can be read by inputting read light from the information recording layer side and reflected light.

The insulating light reflecting layer 12 ′ includes, for example, a dielectric mirror layer, a light-reflecting light-shielding film, and the like. As the dielectric mirror layer, a layer formed of, for example, a combination of silicon dioxide and titanium dioxide, or a combination of zinc sulfide and magnesium fluoride with a film thickness of λ / 4 can be given. As a light-shielding film having light reflectivity, for example, aluminum oxide as an insulating material and germanium as a light-shielding material are deposited at a deposition rate of 50 ° /
Seconds and germanium at a deposition rate of 20 ° / sec, and are simultaneously deposited to a thickness of about 1 μm.

The transparent insulating layer 12 ″ is the insulating light reflecting layer 1.
If the information recording layer 11 is formed directly on the layer 2 ', there is a problem that the insulating light reflecting layer 12' is peeled off. The layer is provided to prevent the peeling and improve the formation of the information recording layer 11. The transparent insulating layer 12 ″ is the same as the above-described intermediate layer 12.

Since the insulating light reflecting layer 12 'and the transparent insulating layer 12 "lower the distribution voltage applied to the liquid crystal layer or deteriorate the resolution similarly to the above-mentioned intermediate layer, the thinner the film, the better. Is preferably 2 μm or less, and more preferably 0.1 μm to 1 μm.

In this information recording medium, the readout light does not pass through the generally colored photoconductive layer when reading out the information, so that the reproduced information can be free of noise.

In each of the first and second information recording media of the present invention, a primer layer is provided between each of the above-mentioned electrode layers, light reflection layers or light reflection prevention layers, and substrates in order to improve adhesion. May be provided.

The primer layer is selected in consideration of the respective materials of the electrode layer, the light reflection layer or the antireflection layer, and the substrate, and is selected from ionizing radiation curable resins such as thermoplastic resins, thermosetting resins, and ultraviolet curable resins. The resin may be formed by coating, or in the case of a combination of an inorganic material and an organic material, a known organic metal compound such as a silane coupling agent, an organic titanium compound, or an organic aluminum compound may be used. Further, a primer layer may be provided between the electrode layer and the information recording layer, and the above-mentioned materials can be used in the same manner, and the film thickness in this case is 0.01 μm to 10 μm. Range. Since the voltage applied to the information recording layer can be controlled by improving the adhesion and changing the film thickness, the recordable exposure range can be controlled.

Further, the first and second information recording media of the present invention are used after being cut into appropriate sizes in the layer width direction according to the usage mode. The inside of the layer is exposed, and the liquid crystal phase exudes 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.

Further, the first and second information recording media of the present invention record electrostatic information in a state where the electrostatic information is visualized by the orientation of liquid crystal. Oriented and visualized information is not erased, providing memory. The memory may be erased by heating to a high temperature near the isotropic phase transition, and can be used again for information recording.

Examples will be described below. In the examples,
"Parts" indicates parts by weight, and "%" indicates% by weight. Further, the liquid crystal used in the embodiments is abbreviated as follows.

[0120]

Embedded image

[0121]

Example 1 A first information recording medium of the present invention was produced as follows. A 100-nm-thick indium tin oxide (ITO) film on a well-cleaned 1.1-mm-thick glass substrate
The film was formed by a sputtering method to obtain an electrode layer of 80Ω / □. On the electrode, a smectic liquid crystal having the following composition: 5.5 parts 1-b 40% 1-c 15% 1-d 15% 2 -A 18% 3-a 2% 3-c 5% 3-d 5% UV curable resin (dipentaerythritol hexaacrylate, trade name: D-310, manufactured by Nippon Kayaku Co., Ltd.) 4.5 parts-Photopolymerization initiator (2-hydroxy-2-methyl-1-phenylpropane-1-one, manufactured by Ciba-Geigy: Darocur, trade name) 1173) ··· 0.22 parts · Surfactant (manufactured by Sumitomo 3M; trade name: Florado FC-430) ··· 0.1 parts with xylene (manufactured by Junsei Chemical Co., Ltd., special grade of reagent) with a solid content of 50 adjust weight%, after spinner coating, and held at 49 ° C., ultraviolet 500 mJ / cm ² Irradiation is performed, the film thickness 6μ
m information recording layers were formed to obtain a first information recording medium of the present invention.

After the liquid crystal was extracted from the cut surface of the obtained information recording layer with hexane and dried, the internal structure was observed with a scanning electron microscope (S-800, manufactured by Hitachi, Ltd., 10000 times). After that, the surface of the layer was covered with resin,
The inside of the layer was filled with resin particles having a diameter on the order of submicron.

(Preparation of Optical Sensor) An indium tin oxide (ITO) film having a thickness of 100 nm was formed on a sufficiently cleaned glass substrate having a thickness of 1.1 mm by a sputtering method.
An Ω / □ electrode layer was obtained.

A solution of bisazo pigment DPDP-3 (manufactured by Dainichi Seika Kogyo Co., Ltd.) as a charge generating agent was coated on the electrode by a blade coater, dried at 100 ° C. for 1 hour and dried to a thickness of 300 nm. Were laminated. On this charge generation layer, a hydrazone-based solution D
After applying PDT-3 (manufactured by Dainichi Seika Kogyo Co., Ltd.) using a spinner, it was dried at 80 ° C. for 2 hours to form a 10 μm-thick photoconductive layer composed of a charge generation layer and a charge transport layer. I got

Next, the obtained optical sensor and the information recording medium produced above were arranged facing each other with a 10 μm PET film as a spacer, and incorporated in the recording apparatus of FIG.

The recording apparatus was exposed to a gray scale for 33 msec from the optical sensor side and a voltage of 650 V and 40 msec was applied between both electrodes. After observing the information recording medium, the transmittance of the gray scale was determined. Thus, the transmittance of the information recording layer changed according to the above, and it was found that the information was recorded.

An image is read with 488 nm light,
When A / D conversion was performed and the image was reproduced at 256 gradations, the image was recorded from 0.01 lux · sec without local noise.

[0128]

[Comparative Example 1] A coating liquid in the information recording layer of the information recording medium of Example 1 was used. ・ Smectic liquid crystal having the following composition: 5.5 parts: 1-b 60% 1-d 15% 2-a 25% UV curable resin (dipentaerythritol hexaacrylate, trade name: D-310, manufactured by Nippon Kayaku Co., Ltd.) 4.5 parts Photopolymerization Initiator (2-hydroxy-2-methyl-1-phenylpropane-1-one, manufactured by Ciba-Geigy: trade name Darocur 1173) 0.22 parts Surfactant (manufactured by Sumitomo 3M: trade name) Florad FC-430) Information was obtained in the same manner as in Example 1 except that 0.3 part was replaced with a solid content of 50% by weight adjusted with xylene (manufactured by Junsei Chemical Co., Ltd., reagent grade). A recording medium was created.

Similarly to Example 1, when the gray scale was projected and exposed from the optical sensor for 33 msec and photographed, a voltage was applied between both electrodes, and photographing became possible by applying a voltage of 700 V for 40 msec. In comparison with Example 1, a higher voltage was required for photographing.

When the image was read with 488 nm light, A / D converted and reproduced at 256 gradations, the image was recorded from 0.01 lux · sec.
Local noise was observed.

[0131]

Example 2 A second information recording medium of the present invention was produced as follows. (Formation of Photoconductive Layer) A 100 nm-thick indium tin oxide (IT) film was formed on a sufficiently cleaned glass substrate having a thickness of 1.1 mm.
O) A film was formed by a sputtering method to obtain an electrode layer of 80Ω / □. A photoconductive layer was laminated on the electrode layer in the same manner as in Example 1.

(Formation of Intermediate Layer) 5 g of polyvinyl alcohol (AT, manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved in 95 g of pure water.
An intermediate layer solution was applied to the previously prepared photoconductive layer using a spinner and dried at 80 ° C. for 1 hour to obtain an intermediate layer having a thickness of 0.6 μm. At this time, the film surface was good without eroding the photoconductive layer.

(Formation of Information Recording Layer) On the obtained intermediate layer, a coating liquid for forming an information recording layer was coated with:-a smectic liquid crystal having the following composition--5.5 parts-1-b- · 40% 1-c ··· 15% 1-d ··· 15% 2-a ··· 18% 3-a ··· 2% 3-c ··· 5% 3- d 5% UV curing resin (dipentaerythritol hexaacrylate, trade name: D-310, manufactured by Nippon Kayaku Co., Ltd.) 4.5 parts Photopolymerization initiator (2-hydroxy-2) -Methyl-1-phenylpropane-1-one, manufactured by Ciba-Geigy: trade name Darocur 1173) 0.22 parts Surfactant (Sumitomo 3M: trade name Florard FC-430) 0 1 part was adjusted with xylene (special grade reagent, manufactured by Junsei Chemical Co., Ltd.) to 50% solids And, after spinner coating, and held at 49 ° C., subjected to ultraviolet irradiation of 500 mJ / cm ^2, thickness 6μ
m information recording layers were formed.

Further, a film having a thickness of 100 nm was formed on the information recording layer.
The indium tin oxide (ITO) film was formed by a sputtering method to form an electrode layer of 80 Ω / □ to obtain a second information recording medium of the present invention.

After the liquid crystal was extracted from the cut surface of the obtained information recording layer with hexane and dried, the internal structure was observed with a scanning electron microscope (S-800, manufactured by Hitachi, Ltd., 10000 times). After that, the surface of the layer was covered with resin,
The inside of the layer was filled with resin particles having a diameter on the order of submicron.

On the information recording medium, a gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 50 V and 40 msec, the information recording medium was observed. As a result, it was found that the transmittance of the information recording layer changed according to the transmittance of the gray scale, and that the information was recorded.

An image is read with 488 nm light,
When A / D conversion was performed and the image was reproduced at 256 gradations, the image was recorded from 0.01 lux · sec without local noise.

[0138]

[Comparative Example 2] The information recording layer of the information recording medium of Example 2 was composed of:-a smectic liquid crystal having the following composition-5.5 parts: 1-b-60% 1-d- ··· 15% 2-a ··· 25% · UV curable resin (dipentaerythritol hexaacrylate, trade name: D-310, manufactured by Nippon Kayaku Co., Ltd.) ··· 4.5 parts · Photopolymerization initiator (2-Hydroxy-2-methyl-1-phenylpropane-1-one, manufactured by Ciba-Geigy: trade name Darocur 1173) 0.22 parts Surfactant (Sumitomo 3M: trade name Florard FC) -430) 0.3 part was adjusted to 50% by weight of solid content with xylene (manufactured by Junsei Chemical Co., Ltd., reagent special grade), and after spinner application, kept at 47 ° C. and irradiated with 500 mJ / cm ² ultraviolet rays. Irradiation, film thickness 6μ
An information recording layer was formed in the same manner as in Example 2 except that the information recording layer was m.

On this information recording layer, an electrode layer of 80Ω / □ was formed in the same manner as in Example 2 to obtain an information recording medium.

When the gray scale was projected and exposed to the information recording medium from the photoconductive layer side for 33 msec and a voltage was applied between both electrodes, photographing became possible by applying a voltage of 400 V and 40 msec. It was necessary to apply a higher voltage during photographing than in the case of.

When the image was read with light of 488 nm, A / D converted and reproduced at 256 gradations, the image was recorded from 0.01 lux · sec.
Local noise was observed.

[0142]

Embodiment 3 The liquid crystal composition in the information recording layer of the embodiment 2 is 1-a 5% 1-b 49.14% 1-d 12.29% 2-a ··· 20.47% 3-a ··· 2% 3-b ··· 2% 3-e · · · 9.10% An information recording medium was obtained in the same manner as in Example 2, except that the temperature was kept at 54 ° C., and the same ultraviolet ray irradiation was performed to obtain the same information recording layer.

In the same manner as in Example 2, the gray scale was projected and exposed for 33 msec from the photoconductive layer side, and 30 g between the two electrodes.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0144]

Embodiment 4 The liquid crystal composition in the information recording layer of the embodiment 2 is 1-a 5% 1-b 50.50% 1-d 12.63% 2-a ··· 21.04% 3-a ··· 2% 3-b ··· 2% 3-d ··· 0.91% 3-e ··· Replaced with 5.92% An information recording medium was prepared in the same manner as in Example 2, except that the coating liquid was similarly prepared, and after spinner application, the temperature was maintained at 50 ° C., and the same ultraviolet ray irradiation was performed to form a similar information recording layer.

In the same manner as in Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0146]

Fifth Embodiment The liquid crystal composition in the information recording layer of the second embodiment is 1-a... 5% 1-b... 50.67% 1-d... 12.67% 2-a ··· 21.11% 3-a ··· 4% 3-b ··· 2% 3-d ··· 1.82% 3-e ··· 2.73% An information recording medium was prepared in the same manner as in Example 2, except that the coating liquid was similarly prepared, and after spinner application, the temperature was maintained at 50 ° C., and the same ultraviolet ray irradiation was performed to form a similar information recording layer.

In the same manner as in Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0148]

Embodiment 6 The liquid crystal composition in the information recording layer of the embodiment 2 is as follows: 1-a 5% 1-b 50.67% 1-d 12.67% 2-a ··· 21.11% 3-a ··· 3% 3-b ··· 3% 3-d ··· 1.82% 3-e ··· 2.73% An information recording medium was prepared in the same manner as in Example 2, except that the coating liquid was similarly prepared, and after spinner application, the temperature was maintained at 50 ° C., and the same ultraviolet ray irradiation was performed to form a similar information recording layer.

In the same manner as in Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0150]

Embodiment 7 The liquid crystal composition in the information recording layer of the embodiment 2 is as follows: 1-b 55.80% 1-d 13.95% 2-a 23.25% 3 -A ... 2% 3-f ... 5% instead of a coating solution, and after spinner application, kept at 50 ° C and similarly irradiated with ultraviolet light to obtain a similar information recording layer. Except for the above, an information recording medium was prepared in the same manner as in Example 2.

In the same manner as in Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0152]

Embodiment 8 The liquid crystal composition in the information recording layer of the embodiment 2 is 1-b ··· 58.80% 1-d ··· 14.70% 2-a ··· 24.50% 3 -A: In the same manner as in Example 2 except that the coating liquid was replaced with 2%, the spinner was applied, the temperature was kept at 52 ° C., the ultraviolet irradiation was performed, and the same information recording layer was formed. As an information recording medium.

As in the case of Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

[0154]

Ninth Embodiment The liquid crystal composition in the information recording layer of the second embodiment is expressed as 1-a 5% 1-b 52.8% 1-d 13.2% 2-a ... 22% 3-b ... 2% 3-e ... 5% instead of a coating solution, and after spinner application, kept at 50 ° C and similarly irradiated with ultraviolet light. An information recording medium was formed in the same manner as in Example 2 except that the same information recording layer was used.

In the same manner as in Example 2, the gray scale was projected and exposed from the photoconductive layer side for 33 msec.
After applying a voltage of 0 V and applying a voltage of 40 msec for the same photographing, the image was read with 488 nm light, A / D converted, and reproduced at 256 gradations.
Recording was performed without local noise from 1 lux · sec.

Further, the information recording layer coating solutions prepared in Examples 3 to 9 were used for forming the information recording layer of the information recording medium in Example 1, and information recording media were prepared in the same manner as in Example 1. . In addition, the holding temperature at the time of irradiating the ultraviolet ray at the time of manufacturing the information recording layer was as in Example 3.
-9, the temperature was the same as the holding temperature at the time of irradiating the ultraviolet rays when the information recording layer was produced.

Each of the obtained information recording media faces the optical sensor in the same manner as in the first embodiment, and is photographed under the same photographing conditions as in the first embodiment. When D-converted and reproduced with 256 gradations,
The image was recorded from 0.01 lux · sec without local noise.

[0158]

According to the information recording medium of the present invention, high-sensitivity recording is possible without noise.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a cross section of a first information recording medium of 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 with transmitted light.

FIG. 4 is a schematic view showing a cross section of a second information recording medium according to the present invention, and FIGS. 4 (a), 4 (b) and 4 (c) are views showing different embodiments.

FIG. 5 is a diagram for explaining a method of recording information on a second information recording medium.

[Explanation of symbols]

1 is an optical sensor, 3 is an information recording medium, 11 is an information recording layer, 12 is an intermediate layer, 12 'is an insulating light reflecting layer, 12 "is a transparent insulating layer, 13 and 13' are electrode layers, and 14 is photoconductive. layer,
15 is a substrate, 18 is an information light, 19 is a spacer, 21 is a light source, 22 is a shutter having a driving mechanism, 23 is a pulse generator (power supply), 24 is a dark box, A is transmitted light,
B is the scattered light.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akinori Takeshige 1-1-1 Ichigaya Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd.

Claims (2)

[Claims] 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 and a fluorine-based surfactant. The liquid crystal phase contains at least one of a 4-alkyl-4'-cyanobiphenyl liquid crystal and a 4-alkoxy-4'-cyanobiphenyl liquid crystal, and is represented by the following general formulas (1) to (4). An information recording medium comprising at least one liquid crystal compound. Embedded image (Wherein A ₁ and B ₁ are divalent groups having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine, R ₁ And R ₂ is an alkyl group or an alkoxy group, and n is an integer of 3 to 15.) (Wherein A ₂ and B ₂ are divalent groups having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine, R ₃ And R ₄ represent an alkyl group or an alkoxy group, respectively. (In the formula, R ₅ and R _{6 each} represent an alkyl group or an alkoxy group, and m represents an integer of 0 or 1.) (In the formula, R ₇ represents an alkyl group or an alkoxy group.) 2. An information recording medium comprising an electrode layer, a photoconductive layer, an information recording layer, and an electrode layer sequentially provided, wherein at least one of the electrode layers is transparent and the information recording layer is a liquid crystal phase. And an information recording medium comprising a liquid crystal, an ultraviolet curable resin and a fluorine-based surfactant, wherein the liquid crystal phase is a 4-alkyl-4'-cyanobiphenyl liquid crystal or a 4-alkoxy-4'-cyanobiphenyl. An information recording medium comprising at least one liquid crystal and at least one liquid crystal compound represented by the following general formulas (1) to (4). Embedded image (Wherein A ₁ and B ₁ are a divalent group having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine, R ₁ And R ₂ represents an alkyl group or an alkoxy group, and n represents an integer of 3 to 15.) (Wherein A ₂ and B ₂ are divalent groups having a skeleton of phenylpyrimidine, biphenyl, phenylbenzoic acid, phenylcyclohexane, phenylbiphenylcarboxylic acid, biphenylbenzoic acid, terphenyl or 1,5-diphenylpyrimidine, R ₃ And R ₄ represent an alkyl group or an alkoxy group, respectively. (In the formula, R ₅ and R _{6 each} represent an alkyl group or an alkoxy group, and m represents an integer of 0 or 1.) (In the formula, R ₇ represents an alkyl group or an alkoxy group.)