JPH08220555A - Optical sensor, information recording device and information recording method - Google Patents

Abstract

PURPOSE: To provide the optical sensor which is free of irregularity in sensitivity and noise, and provide an information recording system. CONSTITUTION: This invention is concerned with an optical sensor which can record information onto an information medium with an intensity amplified by current greater than that caused by information exposure, can keep conductivity if voltage is applied continuously even after information exposure has been over, and thereby continuously keeps recording information onto the information medium, an optical induction current amplifying layer 16 is provided between an electrode 13 and an optical conductive layer 14, wherein the aforesaid amplifying layer exhibits a action to let current flow, which is caused by electric charge 17 injected in addition to optical current while energy barriers over the electrode interface are being flattened by carrier charge which is generated by letting optical carriers be trapped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical sensor capable of recording optical information on an information recording medium in the form of visible information or electrostatic information, and more particularly to a photo-induced current amplifying layer as an electrode and a photoconductive layer. It relates to an optical sensor provided between them. Further, the present invention relates to an information recording apparatus and an information recording / reproducing method comprising the optical sensor and an information recording medium, in particular, the information recording performance on the information recording medium is remarkably amplified to obtain a predetermined image density, and further image unevenness and image The present invention relates to an information recording device, an information recording method, and an information recording / reproducing method, each of which includes an optical sensor having no noise.

[0002]

2. Description of the Related Art An optical sensor composed of a photoconductive layer having an electrode provided on the front surface and an information recording medium composed of a charge holding layer having an electrode provided on the rear surface are arranged on the optical axis, facing the optical sensor. Then, exposure is performed while applying a voltage between both electrode layers, electrostatic charge is recorded on the charge holding layer according to the incident optical image, and the electrostatic charge is subjected to a toner phenomenon or a reproducing method by potential reading is performed by, for example, JP-A-1-290366,
It is described in JP-A-1-289975. Further, a method of visualizing the electrostatic charge recorded by forming a frost image on the surface of the thermoplastic resin in the charge retention layer in the above method is described in, for example, JP-A-3-192288.

Further, the applicant of the present invention uses the polymer-dispersed liquid crystal layer as the information recording layer in the information recording medium, exposes when a voltage is applied in the same manner as described above, and aligns the liquid crystal layer by an electric field formed by a photosensor. The information recording / reproducing method is described in Japanese Patent Application No.
3394, Japanese Patent Application No. 4-24722, Japanese Patent Application No. 6-64
Filed as No. 37. These information recording / reproducing methods can visualize recorded information without using a polarizing plate. However, in such information recording methods, an information recording method having higher sensitivity and higher resolution has been demanded.

[0004]

DISCLOSURE OF THE INVENTION The present invention is an optical sensor used for forming information on an information recording medium, which is a significant problem in an optical sensor having high resolution and high sensitivity. It is an object of the present invention to provide an optical sensor that can obtain a high-quality image without unevenness and noise, is excellent in information forming ability, and has improved information recording sensitivity, an information recording device including the optical sensor, and an information recording / reproducing method.

[0005]

The present invention has a photoconductive layer on an electrode, is semiconductive, and applies a voltage to a photosensor in a state where information is exposed, or a voltage is applied when a voltage is applied. When information is exposed, information can be recorded on the information recording medium with an intensity that is amplified more than the current caused by the information exposure, and if voltage is continuously applied even after the information exposure is completed, the conductivity is maintained and the information continues. In an optical sensor having a function of continuing to record information on a recording medium, an energy barrier at an electrode interface is flattened by a carrier charge generated by trapping photocarriers between an electrode and a photoconductive layer, and a photocurrent is generated. In addition, it is an optical sensor having a photo-induced current amplification layer having a function of causing a current to flow by the injected charges. An optical sensor used for forming information on an information recording medium,
Having a photoconductive layer on the electrodes, which is semi-conductive, a voltage is applied between the electrodes of the photosensor and the electrodes of the information recording medium in a state where information is exposed, or when information is exposed in a state where a voltage is applied, Information can be recorded on the information recording medium with an intensity amplified more than the current caused by the information exposure, and if the voltage is continuously applied even after the information exposure is completed, the conductivity is maintained, and the information is continuously recorded on the information recording medium. In an optical sensor having a function of continuing recording, between the electrode and the photoconductive layer,
An energy barrier at the electrode interface is flattened by carrier charges generated by trapping photocarriers, and has a photoinduced current amplification layer having a function of flowing a current due to injected charges in addition to a photocurrent generated by information exposure. It is an optical sensor.

An optical sensor used for forming information on an information recording medium, which has a photoconductive layer on an electrode, is semiconductive, and is capable of forming information on the electrode by an electric field or a charge amount. It is used by arranging it so as to face the information recording medium in which recording layers are laminated, and voltage is applied between the electrodes of the optical sensor and the electrodes of the information recording medium in the state where information is exposed, or the information is exposed while voltage is applied. Then, information recording can be performed on the information recording medium with an intensity that is amplified more than the current caused by the information exposure, and the conductivity is maintained when the voltage is continuously applied even after the information exposure is completed, and the information recording medium continues. In an optical sensor that has the function of continuing to record information, the energy of the electrode interface is trapped between the electrode and the photoconductive layer due to the carrier charge trapped by the charge trap generated by the photocarrier trapped. Wall is flattened, an optical sensor having a light-induced current amplifying layer having a function to flow a current due to the charge injected in addition to the photocurrent generated by the information exposure.

Also, the above-mentioned optical sensor has a specific resistance of the electrode of 10 ⁶ Ω · cm or less. Relative humidity 6
It is an optical sensor obtained by aging in a dark place of 0% or less. In the above optical sensor, the passing current density in the unexposed portion is 10 ⁻⁴ to 10 ⁻⁷ A / cm ² when an electric field strength of 10 ⁵ to 10 ⁶ V / cm is applied to the optical sensor when a voltage is applied. is there. When the voltage is applied, the conductivity of the exposed area increases more than the conductivity of the unexposed area, and the conductivity of the exposed area is higher than that of the unexposed area while the voltage is applied even after the exposure is completed. The above optical sensor is maintained at a high level, the conductivity in the exposed portion is rapidly reduced after the voltage application is completed and becomes equal to the conductivity in the unexposed portion, and the optical sensor can be repeatedly reused rapidly. 40 to 1 by thermal stimulation current measurement
It is the above optical sensor in which a clear peak is observed in the range of 50 ° C.

In an information recording apparatus for recording optical information on an information recording medium by information exposure, information obtained by connecting the optical sensor and the information recording medium having an information recording layer formed on an electrode on the optical axis with a gap provided therebetween. It is a recording device. In the above information recording device, the information recording layer is composed of a liquid crystal phase and a resin phase. The information recording device is the above-mentioned information recording device in which the information recording layer is made of an ultraviolet curable resin, a liquid crystal, and a surfactant. The information recording device as described above, wherein the liquid crystal is a mixture of a smectic liquid crystal and a nematic liquid crystal. In the above information recording device, the resin phase constituting the information recording layer is composed of an ultraviolet curable resin, and the surface layer of the information recording layer is composed of only a skin layer of the ultraviolet curable resin. The information recording device has the information recording layer having a memory property. To optical sensor 10 ⁵ ~ 1
During the application time of the electric field strength of 0 ⁶ V / cm, the passing current density in the unexposed portion was 10 ^-4 to 10 ^-7 A / cm ² , and the specific resistance of the information recording medium was 10 ¹⁰ to 10 ¹³ Ω. The information recording device is cm. In an information recording device in which a photoconductive layer, a dielectric layer, an information recording layer, and an upper electrode are laminated in this order on the lower electrode, the optical sensor section including the lower electrode and the photoconductive layer is composed of the above-mentioned optical sensor, and the lower electrode and It is an information recording device in which a voltage can be applied between the upper electrode and the upper electrode.

In an information recording / reproducing method for recording optical information on an information recording medium by information exposure, the above-mentioned optical sensor and an information recording medium having an information recording layer formed on electrodes are used, and at least the optical sensor or the information recording medium is used. One of the electrodes is used as a transparent electrode, and the optical sensor and the information recording medium are arranged opposite to each other on the optical axis with a gap, and a voltage is applied between both electrodes to expose the information recording medium by exposing the optical information. It is an information recording / reproducing method of recording information and reproducing optical information recorded on an information recording medium as visible information by transmitted light or reflected light. In the above information recording / reproducing method, the information recording layer in the information recording medium comprises a liquid crystal phase and a resin phase. The information recording / reproducing method described above, wherein the information recording layer in the information recording medium comprises an ultraviolet curable resin, a liquid crystal, and a surfactant. The information recording / reproducing method as described above, wherein the liquid crystal is a mixture of a smectic liquid crystal and a nematic liquid crystal. In the information recording / reproducing method, the resin phase constituting the information recording layer is composed of an ultraviolet curable resin, and the surface layer of the information recording layer is composed only of a skin layer of the ultraviolet curable resin.

In the information recording method for recording optical information on an information recording medium by information exposure, the information recording medium has a photoconductive layer, a dielectric layer, an information recording layer and a game electrode laminated in this order on the lower electrode. An optical sensor unit comprising an electrode and a photoconductive layer comprises the optical sensor according to claim 1, wherein at least one of a lower electrode and an upper electrode is a transparent electrode, and a voltage is applied between the lower electrode and the upper electrode. Is an information recording / reproducing method in which information is recorded on an information recording medium by exposure of optical information while applying light, and optical information recorded on the information recording medium as visible information is reproduced by transmitted light or reflected light. This is an information recording / reproducing method in which recorded optical information is read by a scanner having a CCD sensor and an image is output by a sublimation transfer printer.

The present invention will be described in detail below. The optical sensor in the information recording system of the present invention includes a photoconductive layer laminated on an electrode, and the photoconductive layer includes a single layer type and a laminated type in which a charge generation layer and a charge transport layer are laminated. . The photoconductive layer generally has a function of generating photocarriers (electrons, holes) in the irradiated portion when light is irradiated, and these carriers can move in the layer width. In the photosensor, the energy barrier at the electrode interface is flattened by the carrier charge generated by the trapping of photocarriers between the electrode and the photoconductive layer, so that the current caused by the injected charge flows in addition to the photocurrent. It has a photo-induced current amplification layer.

A single-layer type photosensor in which the photoconductive layer of the photosensor of the present invention is composed of a single layer will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a single-layer type optical sensor, in which 13 is an electrode, 16 is a photoinduced current amplification layer, 14 is a photoconductive layer, and 15 is a substrate. The photoconductive layer 14 is formed of an inorganic photoconductive material or an organic photoconductive material. As the inorganic photoconductive substance, Se, Se-Te, ZnO, Ti
O _2, Si, CdS, and the like, deposited singly or in multiple combinations, sputtering, the electrode on CVD, or the like, 1 to 30 [mu] m, preferably 3~20μm
Are laminated with a film thickness of. Alternatively, the photoconductive layer may be formed by using an inorganic photoconductive substance as fine particles and using a binder. Examples of the binder include silicone resin, polycarbonate resin, vinyl formal resin, vinyl acetal resin, vinyl butyral resin, styrene resin, styrene-butadiene copolymer resin, epoxy resin, acrylic resin, saturated or unsaturated polyester resin, methacrylic resin, Vinyl chloride resin, vinyl acetate resin, vinyl chloride-
Examples thereof include vinyl acetate copolymer resins, and the binder resins can be used alone or in combination of two or more. In this case, 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, of the photoconductive fine particles are dispersed in 1 part by weight of the resin.

Examples of the organic photoconductive substance include a polymer photoconductive substance and a dispersion of a low molecular weight photoconductive substance in an insulating binder. As the polymer photoconductive substance, for example, polyvinylcarbazole (PVK),
Poly-containing an ethylenically unsaturated group such as an allyl group or an acryloxyalkyl group instead of the vinyl group in PVK
There are N-ethylenically unsaturated group-substituted carbazoles, poly-N-ethylenically unsaturated group-substituted phenothiazines such as poly-N-acrylphenothiazine and poly-N- (β-acryloxy) phenothiazine, and polyvinylpyrene. . Among them, poly-N-ethylenically unsaturated group-substituted carbazoles, particularly polyvinylcarbazole are preferably used. Examples of the low molecular weight photoconductive substance include oxadiazoles substituted with an alkylaminophenyl group and the like, triphenylmethane derivatives, hydrazone derivatives, butadiene derivatives, stilbene derivatives and the like. The photoconductive layer may be used by mixing the charge generating substance and the charge transporting substance used in the laminated photosensor in a ratio of 1: 1 to 1:10, preferably 1: 2 to 1: 5. An organic photoconductive layer having a film-forming property is prepared by dispersing 1 part by weight of these organic photoconductive substances in 0.1 to 10 parts by weight, preferably 0.1 to 1 part by weight of an electrically insulating resin. Good.
The film thickness of these organic photoconductive layers after drying is 1 to 50 μm, and preferably 3 to 20 μm and formed on the electrode.
By setting the film thickness in this range, the optical sensor exhibits good sensitivity and image quality.

FIG. 2 is a sectional view for explaining a laminated photosensor in which the photoconductive layer is composed of a charge generation layer and a charge transport layer. In the figure, 13 is an electrode, 16 is a photo-induced current amplification layer,
14 'is a charge generation layer, 14''is a charge transport layer, and 15 is a substrate. The charge generation layer and the charge transport layer forming the photoconductive layer are made of an inorganic material or an organic material.

The charge generation layer 14 'made of an inorganic material is S
e-Te, vapor deposition of silicon doped with sulfur or oxygen,
0.05μ on the electrode by sputtering, CVD, etc.
It is laminated to a film thickness of m to 1 μm. Then, as a charge transport layer, Se, As2Se3, S is formed on the charge generation layer.
i, Si doped with methane or the like is similarly 1 μm to
It may be formed by laminating to a film thickness of 50 μm, preferably 3 to 20 μm. The charge generation layer 14 'made of an organic material is composed of a charge generation substance and a binder. Examples of the charge-generating substance include pyrylium-based dyes, thiapyrylium-based dyes, azurenium-based dyes, cyanine-based dyes, kaolin-based dyes such as azurenium-based dyes, squarylium-salt-based dyes, phthalocyanine-based pigments, perylene-based pigments, and pyranthrone-based pigments. Polycyclic quinone pigment, indigo pigment,
Dyes and pigments such as quinacridone pigments, pyrrole pigments and azo pigments can be used alone or in combination of two or more.

As the binder, for example, silicone resin, polycarbonate resin, vinyl formal resin, vinyl acetal resin, vinyl butyral resin, styrene resin, styrene-butadiene copolymer resin, epoxy resin, acrylic resin, saturated or unsaturated polyester resin, Methacrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin and the like can be mentioned, and each binder resin can be used alone or in combination of two or more. Regarding the mixing ratio of the charge generating substance and the binder, it is desirable to use the binder in an amount of 0.1 to 10 parts by weight, preferably 0.2 to 1 part by weight, relative to 1 part by weight of the charge generating substance. . The charge generation layer has a thickness after drying of 0.01 to 2 μm,
The thickness is preferably 0.1 to 0.5 μm, and such a film thickness exhibits good sensitivity and image quality. Further, among the above-mentioned charge-generating substances, those capable of forming a film by the vapor deposition method can also be formed alone without using a binder.

The charge transport layer 14 '' comprises a charge transport material and a binder. The charge-transporting substance is a substance having a good property of transporting charges generated in the charge-generating layer, and examples thereof include oxadiazole-based, oxazole-based, triazole-based, thiazole-based, triphenylmethane-based, styryl-based, pyrazoline-based, and hydrazone. System, aromatic amine system, carbazole system, polyvinylcarbazole system, stilbene system, enamine system, azine system, triphenylamine system, butadiene system, polycyclic aromatic compound system, stilbene dimer, etc.,
It is necessary to use a substance with good hole transport characteristics. As the binder, the same binders as those used in the charge generation layer described above, and polyarylate resin and phenoxy resin can be used, but styrene resin, styrene-butadiene copolymer resin and polycarbonate resin are preferable. The binder is used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 1 part by weight, based on 1 part by weight of the charge transport material. The charge transport layer has a thickness after drying of 1 to 50 μm, preferably 3 to 20 μm.
It is preferable that the thickness is m, and such a film thickness provides good sensitivity and image quality.

Further, the above-mentioned charge transporting substance which can be formed into a film by the vapor deposition method can also be formed into a film without using a binder. The electrode 13 needs to have transparency if the information recording medium described later is opaque.
When the information recording medium is transparent, it may be transparent or opaque and may be a material that stably gives a specific resistance of 10 ⁶ Ω · cm or less, such as gold, platinum, zinc, titanium, copper, iron,
Metal thin film conductive film such as tin, metal oxide conductive film such as tin oxide, indium oxide, zinc oxide, titanium oxide, tungsten oxide, vanadium oxide, organic conductive film such as quaternary ammonium salt, etc., alone or in combination of two or more. Can be used as a composite material. Of these, oxide conductors are preferable, and indium tin composite oxide (ITO) is particularly preferable. The electrode 13 is formed by vapor deposition, sputtering, CVD, coating, plating,
It is formed by a method such as dipping or electric field polymerization. Further, the film thickness needs to be changed depending on the electrical characteristics of the material forming the electrodes and the applied voltage at the time of recording information.
For example, an ITO film has a thickness of about 10 to 300 nm and is formed over the entire surface between the ITO film and the information recording layer or according to an arbitrary pattern. Further, two or more kinds of materials can be laminated and used.

The substrate 15 is required to have transparency if the information recording medium described later is opaque. However, if the information recording medium has transparency, it may be transparent or opaque. It has the shape of a tape, disk, etc., and strongly supports the optical sensor. If the optical sensor itself has supportability, it need not be provided, and if it has sufficient strength to support the optical sensor,
Many materials can be used. For example, a flexible plastic film, a plastic sheet such as glass, polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, polymethyl acrylate, polyester, or polycarbonate, a card, or the like can be used. When the electrode 13 is transparent, a layer having an antireflection effect is laminated on the other surface of the substrate surface on which the electrode 13 is provided, if necessary, or a film thickness capable of exhibiting the antireflection effect. The antireflection property may be imparted by adjusting a transparent substrate or combining the two.

An electron-accepting substance, an electron-donating substance, a sensitizing dye, an antioxidant, an ultraviolet absorber, a light stabilizer and the like may be added to the photoconductive layer. The electron-accepting substance and the sensitizing dye have the functions of adjusting the base current, stabilizing the base current, and sensitizing. Examples of the electron-accepting substance include nitro-substituted benzenes, amino-substituted benzenes, halogen-substituted benzenes, substituted naphthalenes, benzoquinones, nitro-substituted fluorenones, chloranil compounds and compounds listed in the charge-transporting substance. Examples of the dyes include triphenylmethane dyes, pyrylium salt dyes, xanthene dyes, leuco dyes and the like.

The antioxidants include phenolic antioxidants, sulfur antioxidants and phosphorus antioxidants, and the ultraviolet absorbers include salicylic acid ultraviolet absorbers, benzophenone ultraviolet absorbers and benzotriazole ultraviolet absorbers. Examples of the light absorber and the cyanoacrylate-based UV absorber include a UV stabilizer and a hindered amine-based light stabilizer.

The electron-accepting substance and the sensitizing dye are 0.001 to 10 parts by weight, respectively, relative to 1 part by weight of the photoconductive substance.
It is preferably added in a proportion of 0.01 to 1 part by weight.
If it is less than 0.001 part by weight, no action is shown, and if it is more than 10 parts by weight, the image quality is adversely affected. About antioxidants, ultraviolet absorbers, and light stabilizers, the proportion of 0.001 to 10 parts by weight, preferably 0.01 to 1 part by weight, relative to 1 part by weight of the photoconductive substance, alone or in combination. Is added in. If it is less than 0.001 part by weight, the effect of addition of these substances cannot be obtained, and if it is more than 10 parts by weight, the image quality is adversely affected. In the case of a laminated photosensor, they can be added to the charge generation layer and the charge transport layer in the same ratio. Preferably, these substances are added to the charge generation layer.

That is, in the photosensor of the present invention, trap sites are formed at the interface of the photoinduced current amplification layer 16 formed between the electrode 13 and the photoconductive layer 14 or in the photoinduced current amplification layer. . Charges 1 that are already trapped in this trap site without light
7 exists and is in an energy band state as shown in FIG. When a voltage is applied between both electrodes with the electrode 13 side being positive, an energy barrier as shown in FIG. 3B is generated between the electrode and the photoinduced current amplification layer. Further, when the information light irradiation is performed together with the voltage application, the photocarriers generated with the information light irradiation move in the layer width direction of the photoconductive layer in the voltage applied state, and part of the photocarriers in the process. It is trapped at the interface between the electrode and the photoinduced current amplification layer or at a trap site existing in the photoinduced current amplification layer. As shown in FIG. 3C, the trapped carrier charges cause a distortion in the energy barrier formed between the electrode and the photoinduced current amplification layer, and the energy barrier becomes flat as the accumulation of carriers progresses. Become As a result, a barrier modulation effect occurs and the injection current from the electrode to the photoinduced current amplification layer easily flows.

The trapped charges are accumulated with the passage of time, and in addition to the photocurrent generated by the exposure when a voltage is applied, an injection current due to the barrier modulation effect induced by the trapped charges flows.
It is considered that the apparent photoelectric flow rate is amplified as shown in (D). When the exposure is terminated while maintaining the voltage applied, the photocarriers generated by the exposure are immediately attenuated and disappeared, but the decay of the trapped charges is gradual, so that they are induced by the trapped charges. It is presumed that a sufficient amount of the injection current due to the barrier modulation effect flows while flowing. This photo-induced current is an effect due to amplification due to light in the optical sensor of the present invention, and since a current larger than the incident light flows, it enables effective information recording on the information recording medium. . Thereafter, the trapped charges are attenuated, and along with this, the injection current due to the barrier modulation effect is also attenuated, so that the photo-induced current is also attenuated. Since the decay speed is sufficiently faster than the time of repeated use of the optical sensor of the information recording method of the present invention, the repeated use of the optical sensor becomes possible.

For the photo-induced current amplification layer of the present invention, the same binders as those used in the charge generation layer described above can be used. For example, silicone resin, polycarbonate resin, vinyl formal resin, vinyl acetal resin, vinyl butyral resin, Styrene resin, styrene-butadiene copolymer resin, epoxy resin, acrylic resin, saturated or unsaturated polyester resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, and the like, respectively. The binder resins may be used alone or in combination of two or more. Furthermore, soluble polyamide, phenolic resin, polyurethane, polyurea, casein, polypeptide, polyvinyl alcohol, polyvinylpyrrolidone, maleic anhydride polymer, quaternary ammonium salt-containing polymer, cellulose compound and the like can be used, respectively. The binder resin may be used alone or in combination of two or more. Especially vinyl formal resin,
Vinyl acetal resin and vinyl butyral resin are preferable. The thickness of the photo-induced current amplification layer is 0.005 to 5 μm,
The thickness is preferably 0.05 to 0.5 μm and can be applied by a method such as dip coating, roll coating or spin coating. 0.005 μm
If it is thinner than 5 μm, the effect of reducing image noise is lost, and if it is thicker than 5 μm, injection of charge carriers from the electrode to the charge generation layer is hindered. In addition, various electron-accepting substances, electron-donating substances, photoconductive substances, inorganic salts, and organic salts are added to the photoinduced current amplification layer, if necessary. Can be used.

As the electron accepting substance, for example, 1,3
-Substituted benzene represented by dinitrobenzene, substituted naphthalene, p-benzoquinone, 2,5-dichloro-
Substituted and unsubstituted benzoquinones represented by p-benzoquinone and 2,3-dichloro-5,6-dicyano-p-benzoquinone, substituted and unsubstituted naphthoquinones, substituted and unsubstituted anthraquinones, 2,4,7- Trinitrofluorenone, substituted fluorenones typified by 2,4,5,7-tetranitrofluorenone, p-chloranil, chloranil typified by O-chloranil, 7,
Substituted quinodimethanes represented by 7,8,8-tetracyanoquinodimethane can be mentioned.

As the photoconductive substance, the inorganic and organic photoconductive substances in the above-mentioned single-layer type photosensor and the charge generating substance in the laminated type photosensor can be used. For example, the inorganic photoconductive substance can be used. As Se, Se-
Te, ZnO, TiO ₂ , Si, Si doped with sulfur, oxygen and the like, CdS and the like can be mentioned, and these can be used alone or in combination as a fine particle. As the conductive substance,
For example, polyvinylcarbazole (PVK), poly-N-ethylenically unsaturated group-substituted carbazoles containing an ethylenically unsaturated group such as an allyl group or an acryloxyalkyl group instead of the vinyl group in PVK, and poly-N- Examples thereof include poly-N-ethylenically unsaturated group-substituted phenothiazines such as acrylic phenothiazine and poly-N- (β-acryloxy) phenothiazine, and polyvinylpyrene. Examples of the low molecular weight photoconductive substance among the organic photoconductive substances include oxadiazoles substituted with an alkylaminophenyl group and the like, triphenylmethane derivatives, hydrazone derivatives, butadiene derivatives, stilbene derivatives and the like.

As the charge-generating substance, a pyrrole-based dye, thiapyrylium-based dye, azurenium-based dye, cyanine-based dye, azurenium-based dye, or other KAOTIN-based dye,
Squarylium salt dye, phthalocyanine pigment, perylene pigment, polycyclic quinone pigment such as pyrantrone pigment, indigo pigment, quinatridone pigment, pyrrole pigment, azo pigment, etc. Can be used in combination. Inorganic salts and organic salts include perchlorates, borofluorides, and thiocyanates whose cationic species are metal ions such as lithium, sodium, potassium, magnesium, calcium, and aluminum, quaternary ammonium ions, and organic ions. , Nitrates, carboxylates, sulfonates, halides and the like. These additives are added in a proportion of 0.001 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on 1 part by weight of the binder resin, and the additives may be used alone or in combination. It is preferable to use a combination of an electron-accepting compound and an organic photoconductive pigment, such as a combination of a substituted benzoquinone and an azo pigment, since a large amplifying effect can be obtained.

The photocurrent amplification effect of the photosensor of the present invention is achieved by the following steps: transparent glass, ITO electrode, photoinduced current amplification layer,
It can be measured using an amplification effect measuring optical sensor in which a photoconductive layer is laminated and a gold electrode is laminated on the photoconductive layer. A DC voltage is applied with the ITO electrode as the positive electrode and the gold electrode as the negative electrode, and light is irradiated from the substrate side to start the voltage application,
The behavior of the current value in the optical sensor is measured. It should be noted that the irradiation light is emitted at a illuminance of 20 Lux by using a xenon lamp as a light source and selecting green light with a green filter having the characteristics shown in FIG. When irradiated with light at this light intensity, a transparent substrate,
Considering the light transmittance of the ITO film and the spectral characteristics of the filter, 4.2 × 10 ¹¹ photons / cm ² seconds are incident on the photoconductive layer. Then, when all the incident photons are converted into photocarriers, theoretically a photocurrent and a current of 1.35 × 10 ⁻⁶ A / cm ² per unit area are generated.

Here, in the case of the photo-induced current actually generated in the optical sensor with respect to the theoretical photo-current in the case of measuring by the above-mentioned measured value (photo-induced current value actually generated in the optical sensor / theoretical The photocurrent value) is defined as the quantum efficiency of the photosensor. The photo-induced current is the current value of the light irradiation part minus the base current, which is the current that flows in the part that does not emit light, and is due to light irradiation above the base current during or after light irradiation. It means that a current flows, which is different from so-called photocurrent. The photocurrent amplification action in the photosensor of the present invention is defined as such behavior of photoinduced current.

An optical sensor having a photocurrent amplifying action and an optical sensor having no photocurrent amplifying action (hereinafter referred to as a comparative sensor) according to the present invention will be described with reference to the measurement results of the measuring device. First, the measurement result of the comparative sensor is shown in FIG. In FIG. 5, line (m) is a reference line indicating the theoretical value (1.35 × 10 ⁻⁶ A / cm ² ), and line (n) is an actual measurement line of an optical sensor having no photocurrent amplification effect. It was found that the photocurrent did not increase even during light irradiation, and that it had a constant value, and that constant value was also the theoretical value (1.35).
It does not exceed × 10 ^-6 A / cm ² ). The quantum efficiency of this comparative sensor is almost constant at 0.4. The change in quantum efficiency during light irradiation is indicated by A in FIG. On the other hand, in the photosensor of the present invention, as shown in FIG. 5, the photocurrent is increased during light irradiation, and the quantum efficiency is about 0.01 seconds as shown by B in FIG. It exceeds 1, and the quantum efficiency continues to increase thereafter.

Further, in the comparative sensor, since the photocurrent becomes zero at the same time as the light irradiation, the current does not flow even if the voltage is continuously applied after the light irradiation. On the other hand, in the photosensor of the present invention, the photoinduced current continuously flows by continuing the voltage application even after the light irradiation, and the photoinduced current can be subsequently taken out. Further, the photosensor of the present invention is preferably semiconductive as an element, and has a specific resistance in the dark of 10 ⁹ to 10 ¹³ Ω · cm in view of the flowing current density. In particular, the amplification effect is remarkable when the specific resistance is in the range of 10 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 like the optical sensor of the present invention in the electric field intensity range of 10 ⁵ to 10 ⁶ V / cm, and has a specific resistance of 10 ⁹ Ω. -In the case of an optical sensor of less than cm, a large amount of current flows, and noise due to the current is likely to occur, which is not preferable.

On the other hand, the photoconductor element used in general electrophotography has a dark resistivity of 10 ¹⁴ to 10 ¹⁶ Ω.
The photosensor of the present invention cannot achieve its purpose in electrophotography, and a photosensor having a specific conductive layer with a large dark resistivity for electrophotography is generally used in electrophotography. It cannot be used for the purposes of the invention. Further, between the specific resistance ρ (Ω · cm) of the optical sensor and the current density J (A / cm ² ) of the film pressure d of the optical sensor, the electrode area S, and the applied electric field strength E (V / cm), Since the relational expression of ρ = (E · d / J · S) × (S · d) = E / J is established, it can be obtained from the applied electric field strength and the current density. In the example,
Expressed by current density.

In the expression by the current density, the amplifying action is remarkable especially in the range of the current density in which the value of the base current is 10 ^-4 to 10 ^-7 A / cm ² . Base current is 10 ^-7 A / cm ²
The optical sensor of less than 1 does not show the amplifying effect as the optical sensor of the present invention in the electric field strength range of 10 ⁵ to 10 ⁶ V / cm. On the other hand, in order to set the base current value to 10 ^-7 A / cm ² or more, if an electric field strength of 10 ⁶ V / cm or more is applied, discharge breakdown or image noise will occur, so use with high electric field strength. I can't. Also, the base current is 10
An optical sensor with a voltage of ⁻⁴ V / cm ² or more is very unfavorable because it causes a large amount of current to flow and noise due to the current.

Further, the charge trap site of the photosensor of the present invention is a unique trap site existing in a steady state, and a certain amount of charge is trapped in the charge trap site before optical amplification. Therefore, it can be observed by thermal stimulation current measurement. In addition, although the above-mentioned semi-conductive electric characteristics should originally be difficult to flow current, since they have trap sites and carrier charges are trapped therein to some extent, they exhibit semi-conductive electric characteristics. Conceivable.

Due to the electric charge captured before this optical amplification, the optical sensor of the present invention having an amplifying action has 4
In the range of 0 to 150 ° C., a clear peak-shaped waveform other than the base current is observed, while it is unclear in the sample having no amplification effect. It is considered that this is due to the charges trapped in the trap sites of the optical sensor, and the amplification effect is expected unless the optical sensor accumulates enough electric charge that the peak can be clearly observed in the thermal stimulation current measurement. Can not. Also, the shape of this peak, the value of the peak,
The temperature range and the like differ depending on the material used.

Although the detailed reason is not clear, the optical sensor of the present invention does not stably exhibit sufficient sensitivity immediately after fabrication. Then, in order to fully exhibit the above-mentioned amplification effect, it is necessary to age the optical sensor for a certain period after manufacturing the optical sensor. In particular, the performance can be exhibited by performing the aging in a dark place where the relative humidity is 60% or less.

An information recording device using the optical sensor of the present invention will be described with reference to the drawings. FIG. 8 is a sectional view illustrating an example of the information recording device. The optical sensor 1 and the information recording medium 2 are arranged to face each other with a spacer 19 made of an insulating resin film such as polyimide interposed therebetween. The information recording medium 2 has an electrode 13 ′ of the information recording medium and an information recording layer 11 on a substrate 15, and either one of the electrodes 13 and 13 ′ or both of them may be transparent. A first information recording device for applying a voltage to both electrodes 13 and 13 'is configured.

Next, the second information recording device will be described. FIG. 9 is a cross-sectional view showing a second information recording apparatus of the present invention, in which 20 is a dielectric layer, and the portions denoted by the same reference numerals as those in FIG. 8 have the same contents as those in FIG. Show. Second
In the information recording apparatus, the optical sensor and the information recording medium in the first information recording apparatus are arranged so as to face each other with the dielectric layer 20 in between, and are directly laminated. The second information recording device is
It is particularly suitable when the photoconductive layer in the photosensor is formed by coating using a solvent, and when the information recording layer is directly formed by coating on the photoconductive layer, the liquid crystal in the information recording layer elutes due to their interaction. In addition, it is possible to prevent image unevenness due to the elution of the photoconductive material by the solvent for forming the information recording layer, and it is possible to integrate the optical sensor and the information recording medium. The dielectric layer 20 is
In forming it, it is necessary that it is not soluble in both the photoconductive layer forming material and the information recording layer forming material, and that it is not conductive. In the case of having conductivity, the space charge is diffused and the resolution is deteriorated, so that the insulating property is required. Further, the dielectric layer lowers the distribution voltage applied to the liquid crystal layer or deteriorates the resolution. Therefore, it is preferable that the film thickness is thin, preferably 2 μm or less. As a result, not only image noise is generated due to interaction over time, but also a problem of penetration due to a defect such as a pinhole occurs during multilayer coating. The penetrability due to defects such as pinholes varies depending on the solid content ratio of the material to be laminated and coated, the type of solvent, and the viscosity, so the thickness of the laminated coating is set appropriately, but a thickness of at least 10 μm or less is preferable. , Preferably 0.1 to 3 μm. further,
In consideration of distribution of voltage applied to each layer, it is preferable to use a material having a high dielectric constant as well as a thin film. As a material for forming the dielectric layer, inorganic materials such as SiO ₂ , TiO ₂ , and CeO are used.
₂ , Al ₂ O ₃ , GeO ₂ , Si ₃ N ₄ , AlN, TiN,
Using a combination of MgF ₂ , ZnS, a combination of silicon dioxide and titanium dioxide, a combination of zinc sulfide and magnesium fluoride, a combination of aluminum oxide and germanium, a vapor deposition method, a sputtering method, a chemical vapor deposition (CV
It may be formed by stacking by the method D) or the like. Alternatively, a water-soluble resin having a low compatibility with an organic solvent, for example, an aqueous solution of polyvinyl alcohol, water-based polyurethane, water glass, or the like may be used and laminated by a spin coating method, a blade coating method, a roll coating method, or the like. Further, a coatable fluororesin may be used, and in this case, it 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. The fluororesin which can be applied is, for example, JP-A-4-
Fluorine resins disclosed in Japanese Patent No. 24722 and the like, and organic materials such as polyparaxylylene film-formed in a vacuum system can be preferably used.

For the information recording layer, various information recording media capable of recording a photocurrent obtained by an optical sensor can be used, but it is particularly preferable to use liquid crystal as the information recording layer. Examples of the liquid crystal used as the information recording layer include polymer dispersed liquid crystals. Generally, a polymer-dispersed liquid crystal composed of a polymer resin material and liquid crystal has a structure in which a liquid crystal phase is dispersed in a resin phase in a capsule shape. As the polymer-dispersed liquid crystal, smectic liquid crystal, nematic liquid crystal, cholesteric liquid crystal, or a mixture thereof can be used. In addition, it is preferable to use a smectic liquid crystal from the viewpoint of so-called memory property that retains its orientation and retains information permanently. As smectic liquid crystals, a cyanobiphenyl-based substance having a long carbon group as a terminal group of a substance exhibiting liquid crystallinity,
Liquid crystal substance showing smectic A phase such as cyanota-phenyl type, phenyl ester type and fluorine type, liquid crystal substance showing smectic C phase used as ferroelectric liquid crystal, or liquid crystal showing smectic H, G, E, F, etc. Examples include substances.

As the resin material used for the resin phase, various polymer materials can be used.

The material for forming the resin particles is, for example, an ultraviolet curable resin that is compatible with the liquid crystal material in the monomer or oligomer state, or a solvent common to the liquid crystal material in the monomer or oligomer state. Those having compatibility with can be preferably used. Examples of such an ultraviolet curable resin include acrylic acid ester and methacrylic acid ester. In addition, solvent-soluble thermosetting resins that are compatible with the same solvent as the liquid crystal material, such as acrylic resin, methacrylic resin, polyester resin, polystyrene resin, and copolymers mainly containing these, epoxy resin, silicone resin Etc. may be used. Further, a polyfunctional monomer such as dipentaerythritol hexaacrylate, a photo-curing initiator, a smectic liquid crystal or a mixture of a smectic liquid crystal and a nematic liquid crystal, a coating solution obtained by uniformly dissolving a fluorine-containing surfactant in an organic solvent is prepared. The information recording layer obtained by coating the electrode surface on the substrate and then curing the coating film by UV irradiation has a surface covered with a UV-curable resin, and a liquid crystal forming a continuous phase inside the layer. It is preferable to use an information recording layer made of a polymer-dispersed liquid crystal filled with a resin particle phase having a small particle diameter as an information recording medium.

The material for forming the resin particles is, for example, an ultraviolet curable resin that is compatible with the liquid crystal material in the monomer or oligomer state, or a solvent common to the liquid crystal material in the monomer or oligomer state. Those having compatibility with can be preferably used. Examples of such an ultraviolet curable resin include acrylic acid ester and methacrylic acid ester. In addition, solvent-soluble thermosetting resins that are compatible with the same solvent as the liquid crystal material, such as acrylic resin, methacrylic resin, polyester resin, polystyrene resin, and copolymers mainly containing these, epoxy resin, silicone resin Etc. may be used. The liquid crystal material and resin used for forming the information recording layer may be used so that the content of the liquid crystal is 10% by weight to 90% by weight, preferably 40% by weight to 80% by weight. If it is present, even if the liquid crystal phase is aligned by information recording, the light transmittance is low, and if it exceeds 90% by weight, a phenomenon such as exudation of the liquid crystal occurs, resulting in image unevenness, which is not preferable. Since the film thickness of the information recording layer affects the resolution, the film thickness after drying is 0.1 μm to 10 μm, preferably 3 μm.
The range of m to 8 μm is preferable, and the operating voltage can be lowered while maintaining high resolution. If the film thickness is too thin, the contrast of the information recording portion will be low, and if it is too thick, the operating voltage will be high, which is not preferable. As described above, as the information recording medium, the recording by the information exposure is made visible by the alignment of the liquid crystal, but by selecting the combination of the liquid crystal and the resin, the information once aligned and the visualized information can be erased. Instead, a memory property can be provided. Further, by heating to a high temperature near the isotropic phase transition, the memory property can be erased, so that it can be used for recording information again.

Further, as an information recording medium in the information recording apparatus, in addition to the information recording layer using liquid crystal, for example, JP-A-3-7942, JP-A-5-107775, JP-A-5-107776, and JP-A-5-10776. No. 107777,
An electrostatic information recording medium may be used when the charge storage layer described in JP-A-4-70842 is used as an information recording layer. In this case, information is stored in the information recording medium in the form of electrostatic charge. Therefore, the electrostatic charge is developed by toner, or the electrostatic charge is developed by, for example, Japanese Patent Laid-Open No. 1-29033.
As described in Japanese Patent No. 66, etc., it can be reproduced by potential reading. Further, an information recording medium having a thermoplastic resin layer as an information recording layer described in JP-A-4-46347 may be used. In this case, the information is recorded in the form of electrostatic charge in the same manner as described above. When the thermoplastic resin layer is heated after being accumulated on the surface, information can be accumulated as a frost layer and reproduced as visible information.

Next, an information recording method in the first and second information recording devices of the present invention will be described. Figure 10
FIG. 6 is a diagram for explaining an information recording method in the first information recording device of the present invention. The same applies to the second information recording device. In the figure, 11 is an information recording layer, 13 is an electrode of an optical sensor, 13 'is an electrode of an information recording medium, 16 is a photoinduced current amplification layer, 14 is a photoconductive layer, 21 is a light source, 22 is a shutter having a drive mechanism, Reference numeral 23 is a pulse generator that serves as a power source, and 24 is a dark box. When information light is incident from the light source 21 while applying an appropriate voltage by the pulse generator 23 between the electrodes 13 and 13 ′, the photo carriers generated in the photoconductive layer 14 at the portion where the light is incident are generated on both electrodes. Is moved to the interface on the information recording layer 11 side by the electric field formed by the above, and the voltage is redistributed.
The liquid crystal layer is aligned, and recording is performed according to the pattern of the information light.

In the information recording method of the present invention, planar analog recording is possible, and when liquid crystal is used as the information recording medium, information recording is possible with the size of the liquid crystal as a basic unit. High-resolution recording is achieved, and the exposure pattern is retained as a visible image due to the orientation of the liquid crystal phase. As a form of the information recording system, there are a camera method and a laser recording method. As a method using a camera, an information recording medium is used as a recording member instead of a photographic film used in a normal camera, and an optical shutter can be used and an electric shutter can also be used. You can Further, the optical information is separated into R, G, and B light components by a prism and a color filter and taken out as parallel light to form one frame with three information recording media for each of R, G, and B, or Color recording can also be performed by recording R, G, and B images on different portions of one information recording medium to form one frame.

The laser recording method is as follows.
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. An analog recording such as an image is performed by modulating the light intensity of the laser, and a digital recording such as a character, a code or a line drawing is performed by ON / OFF control of the laser light. Further, in the image, halftone dots are formed by performing dot generator ON-OFF control on laser light. The spectral characteristic of the photoconductive layer in the optical sensor does not need to be panchromatic, and may be sensitive to the wavelength of the laser light source.

The exposure information recorded on the information recording medium is separated from the information recording medium in the case of the first information recording apparatus as shown in FIG. 11 and is kept as it is in the case of the second information recording apparatus. When the information 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, while the light B is scattered in the portion where the information is not recorded and the information recording portion The contrast of is obtained. Also,
You may read by reflected light via a light reflection layer. As shown in FIG. 10 in which this laminated body is incorporated, in the first information recording apparatus, for example, the optical sensor and the information recording medium of the present invention are attached in place of the photographic film of the imaging camera (for example, RB67 manufactured by Mamiya). , DC voltage of 700V between both electrodes of optical sensor and information recording medium 0.04
For 1/30 seconds,
By performing projection exposure from the side of the optical sensor, a recording portion including a light transmitting portion corresponding to gray scale is formed in the information recording layer of the information recording medium, and information recording can be performed.

Next, the information recorded on the information recording medium is read by the information output device shown in FIG. 12 by an image scanner having a CCD line sensor, and the information is read by a sublimation transfer printer (for example, Victor Company of Japan). A good printed matter corresponding to a gray scale can be obtained by outputting information using SP-5500 manufactured by Co., Ltd. The information recorded by the orientation of the liquid crystal is visible information that can be visually read, but it can also be read by enlarging it with a projector, and can read the information with high accuracy using laser scanning or a CCD. . If necessary, scattered light can be prevented by using a Schlieren optical system.

[0050]

In the photosensor of the present invention, by providing the photoinduced current amplification layer between the photoconductive layer and the electrode, the charge carrier injection between the electrode and the photoconductive layer is stably controlled and no light irradiation is performed. At the same time, the conductivity of the entire photosensor element is made semiconductive, and the effect of eliminating partial or local sensitivity unevenness of the photosensor which is likely to occur at the time of light irradiation is promising and has an amplifying effect. The detailed reason for this property is unknown,
Not all of the photocarriers generated by the irradiation of information light move in the layer width direction of the photoconductive layer when a voltage is applied, and some of the photocarriers are trapped at the trap site existing in the photoinduced current amplification layer. The trapped charge is accumulated over time, and in the state where voltage is applied, in addition to the photocurrent generated by exposure, the trapped carrier charge flattens the energy barrier at the electrode interface. Therefore, since it has a function of causing a current due to the injected charges to flow in addition to the photocurrent, it is considered that the injection current from the electrode flows to amplify the apparent photocurrent. When the exposure is terminated while maintaining the voltage applied, the photo carriers generated by the exposure immediately decay and disappear, but the decay of the trapped charges is slow, so the photo carriers are induced by the trapped charges. It is presumed that a sufficient amount of the injected current from the electrode is flowed while it is attenuated.

The trap sites existing in the photo-induced current amplification layer are partially filled before the light irradiation,
It is considered that the injection of charge carriers from the electrode to the photoconductive layer can be stably controlled by providing a photoinduced current amplification layer in which this state is set to a predetermined value between the electrode and the photoconductive layer. To be As a result, the conductivity of the entire photosensor element when not irradiated with light can be made semiconducting, which is the conductivity range of the present invention, and at the same time, the nonuniformity at the interface between the electrode and the photoconductive layer It is presumed that it is caused by nonuniform charge carrier injection from the electrode to the photoconductive layer, which is likely to occur due to contact. It is considered that the local unevenness observed as is eliminated.

As a result, when the optical sensor of the present invention is used to record information on an information recording medium, it is possible to perform high-sensitivity and high-quality information recording without sensitivity unevenness and noise.

[0053]

Embodiments of the present invention will be described below. Example 1 (Preparation of coating liquid for producing photoinduced current amplification layer)

[0054]

Embedded image

3 parts by weight of a fluorenone azo pigment having
1 part by weight of polyvinyl butyral resin was mixed with 98 parts by weight of 1,4-dioxane and 98 parts by weight of cyclohexanone, and sufficiently kneaded with a mixer to obtain a pigment dispersion liquid. In this pigment dispersion, 1 mol of the pigment was used as an electron-accepting substance having the following structure.

[0056]

Embedded image

2,5-dichloro-p-benzoquinone 0.
1 mol was completely dissolved to obtain a coating liquid for photoinduced current amplification layer.

(Production of Laminated Optical Sensor) An ITO film having a sheet resistance of 80 Ω / port and a film thickness of 100 nm was formed on a sufficiently washed glass substrate having a thickness of 1.1 mm by sputtering to obtain an electrode. Scrubber cleaning machine for electrodes (trade name: Plate Cleaner Model 602 Ultratech)
At this time, the cleaning treatment was performed twice: pure water spraying 2 seconds, scrubber cleaning 20 seconds, pure water rinse 15 seconds, water removal by high speed rotation 25 seconds, and infrared drying 55 seconds. The photo-induced current amplification layer preparation coating solution prepared above was applied on this electrode by a spinner while rotating at 4000 rpm for 0.4 seconds, and the coating solution was left standing in a dust-free state for leveling and drying.
After drying at 0 ° C. for 0.5 hour, a photoinduced current amplification layer having a film thickness of 100 nm was laminated. On the photo-induced current amplification layer, the following structure was used as a charge generating substance.

[0059]

Embedded image

Pyrrolopyrrole pigment having (manufactured by Ciba-Geigy) was vapor-deposited under a vacuum of 10 ⁻⁶ Torr at a rate of 3 nm / sec to form a 200 nm layer, which was left in acetone vapor for 1 hour. A charge generation layer was prepared. Next, on the charge generation layer, the following structure was formed as a charge transporting substance.

[0061]

[Chemical 4]

5 parts by weight of a biphenylamine derivative having 1 part by weight of a polycarbonate resin (Iupilon Z-200 manufactured by Mitsubishi Gas Chemical Co., Inc.) and 14 parts by weight of dichloromethane,
22 parts by weight of 1,1,2-trichloroethane are uniformly dissolved to obtain a coating solution, which is spinner at 400 rpm, 0.4
It is applied for 2 seconds, and the film is formed on the surface of the coating film, left to stand in a windless state for leveling drying until the surface does not adhere, and then dried at 80 ° C. for 2 hours to laminate the charge transport layer. And the film thickness consisting of the charge generation layer and the charge transport layer is 10 μm.
A photosensor having a photoconductive layer of
%, And aging was performed in a dark place.

(Electrical Characteristics of Optical Sensor) In order to measure the electrical characteristics of the obtained optical sensor, 0.16 cm ² , thickness of 10 nm and surface resistance of 1 were formed on the charge transport layer of the optical sensor.
A gold layer of kΩ / □ was vapor-deposited to form an electrode, which was used as a measurement optical sensor. It was mounted on a current measuring device as shown in FIG. In the figure, 15 is a photosensor support, 13 is a photosensor electrode, 16 is a photoinduced current amplification layer, 14 is a photoconductive layer consisting of a charge generation layer and a charge transport layer, 30 is a gold electrode, 31 is a light source, and 32 is A shutter (No. 0 electromagnetic shutter manufactured by Copal), 33 is a shutter drive mechanism, 34 is a pulse generator (manufactured by Yokogawa Hewlett-Packard), and 35 is an oscilloscope. In this current measuring device, a DC voltage of 150 V (15 V / μm) was applied between both electrodes with the electrode 13 in the photosensor being positive and the gold electrode being negative, and 0.5 seconds after the start of voltage application, the glass substrate Light was irradiated from the side for 0.033 seconds, and the light irradiation start time was set to t = 0, and the current flowing through the photosensor was measured. As the irradiation light, a xenon lamp (L2274 manufactured by Hamamatsu Photonics KK) was used as a light source, and green light obtained by a green filter (manufactured by Nippon Vacuum Optical Co., Ltd.) was irradiated at an intensity of 20 lux. The irradiation light intensity was measured with an illuminometer (manufactured by Minolta), and the characteristics of the filter used are shown in FIG.

After the light irradiation is completed, the voltage application is continued and the light irradiation is continued.
The voltage application was continued for 0.15 seconds from the irradiation start time. That
The time change of the current between was measured by an oscilloscope.
In addition, only voltage application is performed without exposure, and electricity is similarly applied.
Flow measurement results are also shown. The measurement was performed at room temperature. So
The results are shown in FIG. Horizontal axis shows voltage application time (sec), vertical
The axis is the current density (10 ^-6A / cm²). Figure smell
The (A) line is the measured current value when exposed, and the (B) line is
This is the case where only the voltage is applied without exposure. (A) line
As shown in FIG.
, Two inflection points (a) and (b) are observed. Inflection point
The current amount below (a) is the ratio to the comparison sensor described later.
From the comparison, the current corresponding to the exposure amount (hereinafter referred to as photoinduced current
U) amount. Also, the inflection point (b) is dew
This is the point where the amount of current changes with the end of light,
Even when unexposed, the current corresponding to the applied voltage continues to flow and
It can be seen that it gradually decreases. That is, this figure
, The photosensor in the present invention is
Flow continues to increase and the photo-induced current persists after exposure,
It can be seen that it decays over time. This light sensor
From the value of the current flowing in¹¹In Ω · cm
It was. Also, apparent quantum efficiency was calculated and shown in FIG.
did. In the optical sensor of the present invention, the quantum efficiency is significantly higher than 1.
The maximum value was close to 8.

(Production of Information Recording Medium) A 100 nm-thick ITO film was formed by sputtering on a glass substrate having a thickness of 1.1 mm to obtain an electrode, and then the surface was washed. On this electrode, a polyfunctional monomer (dipentaerythritol hexaacrylate, manufactured by Toagosei Kagaku Kogyo, M-
400) 40 parts by weight, photocuring initiator (2-hydroxy-
2 parts by weight of 2-methyl-1-phenylpropan-1-one, Ciba Geigy, Darocur 1173, 90% liquid crystal (smectic liquid crystal (Merck S-6), nematic liquid crystal (Merck E31LV)) Containing 10%)
A coating solution obtained by uniformly dissolving 50 parts by weight and 3 parts by weight of a surfactant (Sumitomo 3M, Florard FC-430) in 96 parts by weight of xylene was prepared using a blade coater set at intervals of 50 μm. After coating, the coating film is dried at 47 ° C. for 3 minutes, and then dried at 47 ° C. for 2 minutes under reduced pressure, and the coating film is immediately cured by irradiation with 0.3 J / cm ² of ultraviolet light, and an information recording layer having a thickness of 6 μm is recorded. A recording medium was obtained. After extracting the liquid crystal from the information recording layer surface with hot methanol and drying it, a scanning electron microscope (manufactured by Hitachi Ltd.)
When the internal structure was observed with S-800) at a magnification of 1000 times, the surface of the layer was covered with an ultraviolet curable resin having a thickness of 0.6 μm, and the inside of the layer had a particle size of 0.1 μm in a liquid crystal phase forming a continuous layer.
It had a structure filled with m resin particle phase.

(Information recording method and recording characteristics) The obtained optical sensor and information recording medium are set as shown in FIG.
The polyimide films having a thickness of 10 μm were laminated so as to face each other with an air gap provided therebetween. As shown in FIG. 10, this laminated body is provided with an imaging camera (RB6 manufactured by Mamiya Co., Ltd.).
7) was replaced with a photographic film, and a DC voltage of 700 V was applied for 0.04 seconds between both electrodes of the photosensor and the information recording medium, and at the same time, the grayscale exposure amount was 0.2-2.
Projection exposure was performed from the photosensor side at 00 lux for 1/30 seconds. After the exposure, the information recording medium was taken out. When the information recording medium was observed with transmitted light, a recording portion composed of a light transmitting portion corresponding to a gray scale was observed in the information recording layer, and the sensitivity was remarkably improved as compared with the comparative example, and recording was also performed. The image was free from image unevenness and image noise caused by partial or local sensitivity unevenness of the optical sensor, and a good recorded image was obtained.

Next, the recorded information on the information recording medium was reproduced by the information output device shown in FIG. Information recorded on the information recording medium is read by a scanner using a CCD line sensor, and the information is output using a sublimation transfer printer (SP-5500 manufactured by Victor Company of Japan, Ltd.). As a result, gradation corresponding to a gray scale is obtained. A good printed matter having the property of being free from image unevenness and image noise was obtained.

(Measurement of Thermally Stimulated Current of Optical Sensor) In the optical sensor of the present invention, since a certain amount of electric charge is trapped in the charge trap site before the optical amplification, the thermally stimulated current can be measured. is there. Film thickness 30 nm, surface resistance 1 kΩ / mouth, 0.16 cm ² on photoconductive layer of photo sensor
1 was prepared using a short-circuit thermally stimulated current measuring device (manufactured by Toyo Seiki Seisakusho Co., Ltd.).
With the current measuring device shown in 6, the electrode of the optical sensor is positive,
With a gold electrode as a negative electrode, a DC voltage of 1.5 V / μm is applied between both electrodes, and at the same time, the current flowing when the measurement optical sensor is heated at a temperature rising rate of 10 ° C./min Was measured 3 days after the production of the optical sensor. In the figure, 15 is an optical sensor support, 13 is an optical sensor electrode,
Reference numeral 16 is a photo-induced current amplification layer, 14 is a photoconductive layer including a charge generation layer and a charge transport layer, 30 is a gold electrode, 100 is a minute ammeter, 101 is a DC power source, and 100 and 101 are minute ammeters. A direct current power source (HP4140B manufactured by Hewlett-Packard Co.) was used.

The temperature of the sample was measured by an alumel chromel thermocouple in the vicinity of the sample in the sample mounting portion covered with a heat insulating cover. Results are shown in FIG. The horizontal axis represents the heating temperature (° C), and the vertical axis represents the current value (A). As shown in the line (A), in the photosensor having the photoinduced current amplification layer of the present invention, a clear peak-shaped waveform was observed in the range of 50 to 110 ° C. in addition to the base current, and at around 88 ° C. A peak is generated, and at that peak, 4.4 × 10 ⁻⁷ A / c
The current density was m ² .

Comparative Example 1 An optical sensor was manufactured in the same manner as in Example 1 except that the photoinduced current amplification layer was not provided. The electrical characteristics of this optical sensor were measured using the same current measuring device as in Example 1. The result is shown in FIG. From the figure, almost no increase in photocurrent due to light irradiation was observed, and the amount of current contributing to information recording was small. FIG. 19 shows the result of calculating the quantum efficiency as in Example 1. A similar information recording apparatus was manufactured using this comparative sensor and the information recording medium, and a DC voltage of 700 V was applied between both electrodes for 0.04 seconds, and at the same time, projection exposure was performed from the photosensor side. After the exposure, the information recording medium was taken out and read and output by the same information output device as described above, but the information recording medium was recorded only in the extremely narrow range of exposure amount of gray scale. In addition, in the recorded medium, image unevenness and white spots-like noise, which are presumed to be caused by partial or local non-uniformity of the optical sensor, were observed. Further, the thermal stimulation current measurement was performed in the same manner as in Example 1, and the result is shown in the line (B) of FIG. As shown in the line (B), in the photosensor without the photo-induced current amplification layer, 50 to 11
Within the range of 0 ° C, a peak-shaped waveform is observed in addition to the base current, but the peak is very small,
The current density at the peak near ℃ is also 4.5 × 10 ^-8 A
It was a very small value such as / cm ² .

Example 2 (Fabrication of laminated optical sensor) Instead of the electron-accepting substance of Example 1, the following structure was used.

[0072]

Embedded image

An optical sensor was produced in the same manner as in Example 1 except that 7,7,8,8-tetracyanoquinodimethane having (Characteristics of Optical Sensor) The electrical characteristics of this optical sensor were measured using the same current measuring device as in Example 1, and the results are shown in FIG. An increase in photocurrent was observed in response to light irradiation. Image recording was performed on the obtained optical sensor and the information recording medium manufactured in the same manner as in Example 1 in the same manner as in Example 1. The recorded image did not show image unevenness or image noise caused by partial or local sensitivity unevenness of the optical sensor, and good image recording was obtained. As a result of reading this information recording medium in the same manner as in Example 1 and outputting information, a good printed matter having gradation characteristics according to gray scale and free from image unevenness and image noise was obtained.

Example 3 (Fabrication of Laminated Photosensor) Instead of the electron accepting substance of Example 1, the following structure was used.

[0075]

[Chemical 6]

2,3-dichloro-5,6-dicyano-p
An optical sensor was produced in the same manner as in Example 1 except that benzoquinone was used. (Characteristics of Optical Sensor) The electrical characteristics of this optical sensor were measured using the same current measuring device as in Example 1, and the results are shown in FIG. From the figure, an increase in photocurrent was observed in response to light irradiation.

Image recording was performed on the obtained optical sensor and the information recording medium manufactured in the same manner as in Example 1 in the same manner as in Example 1. The recorded image did not show image unevenness or image noise caused by partial or local sensitivity unevenness of the optical sensor, and good image recording was obtained. As a result of reading this information recording medium in the same manner as in Example 1 and outputting information, a good printed matter having gradation characteristics according to gray scale and free from image unevenness and image noise was obtained.

Example 4 (Preparation of coating liquid for producing photoinduced current amplification layer)

[0079]

[Chemical 7]

3 parts by weight of a disazo pigment having 1 part by weight of polyvinyl acetal resin and 1,4-dioxane 9 parts
8 parts by weight and 98 parts by weight of cyclohexanone were mixed and sufficiently kneaded by a mixer to obtain a pigment dispersion liquid. In this pigment dispersion, 1 mol of the pigment was used as an electron-accepting substance having the following structure.

[0081]

Embedded image

Pyrrolopyrrole pigment having (manufactured by Ciba Geigy) was vapor-deposited under a vacuum of 10 ⁻⁶ Torr at a rate of 3 nm / sec to form a 200 nm layer, which was left in acetone vapor for 1 hour. A charge generation layer was prepared. Next, on the charge generation layer, the following structure was formed as a charge transporting substance.

[0083]

[Chemical 9]

5 parts by weight of a biphenylamine derivative containing 1 part by weight of a polycarbonate resin (Iupilon Z-200 manufactured by Mitsubishi Gas Chemical Co., Inc.) and 14 parts by weight of dichloromethane,
22 parts by weight of 1,1,2-trichloroethane are uniformly dissolved to obtain a coating solution, which is spinner at 400 rpm, 0.4
It is applied for 2 seconds, a coating is formed on the surface of the coating, and leveling drying is carried out by leaving it in a windless state until the surface of the coating is not adhered. And a film thickness consisting of a charge generation layer and a charge transport layer 1
An optical sensor according to the present invention having a photoconductive layer of 0 μm was prepared. The optical sensor was aged in a dark place with a relative humidity of 60% or less.

(Characteristics of Optical Sensor) The electrical characteristics of this optical sensor were measured using the same current measuring device as in Example 1, and the results are shown in FIG. From the figure, an increase in photocurrent was observed in response to light irradiation.

Image recording was performed on the obtained optical sensor and the information recording medium produced in the same manner as in Example 1 in the same manner as in Example 1. The recorded image did not show image unevenness or image noise caused by partial or local sensitivity unevenness of the optical sensor, and good image recording was obtained. As a result of reading this information recording medium in the same manner as in Example 1 and outputting information, a good printed matter having gradation characteristics according to gray scale and free from image unevenness and image noise was obtained.

Example 5 (Fabrication of Laminated Photosensor) Instead of the charge-generating substance of Example 1, the following structure was used.

[0088]

[Chemical 10]

An optical sensor was produced in the same manner as in Example 4 except that the pyrrolopyrrole pigment having the formula (Ciba Geigy) was used. (Characteristics of Optical Sensor) The electrical characteristics of the optical sensor were measured using the same current measuring device as in Example 1, and the results are shown in FIG. From the figure, an increase in photocurrent was observed in response to light irradiation.

Image recording was performed on the obtained optical sensor and the information recording medium produced in the same manner as in Example 1 in the same manner as in Example 1. The recorded image did not show image unevenness or image noise caused by partial or local sensitivity unevenness of the optical sensor, and good image recording was obtained. As a result of reading this information recording medium in the same manner as in Example 1 and outputting information, a good printed matter having gradation characteristics according to gray scale and free from image unevenness and image noise was obtained.

Example 6 (Fabrication of Multilayer Photosensor) Instead of the charge generating substance of Example 1, the following structure was used.

[0092]

[Chemical 11]

An optical sensor was produced in the same manner as in Example 4 except that the pyrrolopyrrole pigment having the formula (made by Ciba Geigy) was used. (Characteristics of Optical Sensor) The electrical characteristics of the optical sensor were measured using the same current measuring device as in Example 1, and the results are shown in FIG. From the figure, an increase in photocurrent was observed in response to light irradiation.

Image recording was performed on the obtained optical sensor and the information recording medium manufactured in the same manner as in Example 1 in the same manner as in Example 1. The recorded image did not show image unevenness or image noise caused by partial or local sensitivity unevenness of the optical sensor, and good image recording was obtained. As a result of reading this information recording medium in the same manner as in Example 1 and outputting information, a good printed matter having gradation characteristics according to gray scale and free from image unevenness and image noise was obtained.

[0095]

When the information is recorded on the information recording medium and the voltage is continuously applied after the information exposure is finished, the increased conductivity is maintained, and the light having the action of continuing the information recording on the information recording medium. Since the sensor has a large amplification effect and uniform characteristics, it is possible to obtain an excellent image without image unevenness and noise.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating a single-layer photosensor.

FIG. 2 is a cross-sectional view illustrating a laminated photosensor in which a photoconductive layer includes a charge generation layer and a charge transport layer.

FIG. 3 is a diagram illustrating an energy band state.

FIG. 4 is an illustration without explaining the characteristics of the filter used.

FIG. 5 is a diagram illustrating characteristics of an optical sensor having a photocurrent amplifying action and an optical sensor having no photocurrent amplifying action according to the present invention.

FIG. 6 is a diagram illustrating a change in quantum efficiency during light irradiation of an optical sensor having no amplification effect.

FIG. 7 is a diagram illustrating a change in quantum efficiency during light irradiation of an optical sensor having an amplification effect.

FIG. 8 is a cross-sectional view illustrating an example of an information recording device.

FIG. 9 is a diagram illustrating a second information recording device.

FIG. 10 is a diagram illustrating an information recording method using the information recording device of the present invention.

FIG. 11 is a diagram illustrating a method of reproducing recorded information.

FIG. 12 is a diagram illustrating an information output device.

FIG. 13 is a diagram illustrating a current measuring device.

FIG. 14 is a diagram illustrating characteristics of the optical sensor of the present invention.

FIG. 15 is a diagram illustrating quantum efficiency of the optical sensor of the present invention.

FIG. 16 is a diagram illustrating a current measuring device.

FIG. 17 is a diagram for explaining the results of thermal stimulation current measurement of the optical sensor of the present invention.

FIG. 18 is a diagram illustrating characteristics of the optical sensor of the present invention.

FIG. 19 is a diagram illustrating quantum efficiency.

FIG. 20 is a diagram illustrating characteristics of the optical sensor of the present invention.

FIG. 21 is a diagram illustrating characteristics of the optical sensor of the present invention.

[Explanation of symbols]

1 ... Optical sensor, 2 ... Information recording medium, 13 ... Electrode, 1
3 '... Electrode, 14 ... Photoconductive layer, 14' ... Charge generation layer, 1
4 '' ... Charge transport layer, 15 ... Substrate, 16 ... Photoinduced current amplification layer, 17 ... Charge, 19 ... Spacer, 11 ... Information recording layer, 20 ... Dielectric layer, 21 ... Light source, 22 ... Driving mechanism Shutter, 23 ... Pulse generator, 24 ...
Dark box, 30 ... Gold electrode, 31 ... Light source, 32 ... Shutter,
33 ... Shutter drive mechanism, 34 ... Pulse generator, 35 ... Oscilloscope, 41 ... Information recording medium scanner, 42 ... Personal computer, 43 ... Printer

Claims (23)

[Claims] 1. An information recording medium, which has a photoconductive layer on an electrode, is semiconductive, and is applied with a voltage in a state where information is exposed to a photosensor, or when information is exposed in a state where a voltage is applied. Information can be recorded with an intensity amplified more than the current caused by the information exposure, and if the voltage is continuously applied even after the information exposure is completed, the conductivity is maintained, and the information recording is continued on the information recording medium. In the photosensor having the action, the energy barrier at the electrode interface is flattened by the carrier charge generated by the trapping of the photocarrier between the electrode and the photoconductive layer, and the current caused by the injected charge is added to the photocurrent. An optical sensor having a photo-induced current amplification layer having a function of flowing a current. 2. An optical sensor used for forming information on an information recording medium, which has a photoconductive layer on an electrode and is semiconductive, and information between the electrode of the optical sensor and the electrode of the information recording medium. When voltage is applied in the exposed state or information is exposed in the state where voltage is applied, information can be recorded on the information recording medium with an intensity amplified more than the current caused by the information exposure, and the information exposure is completed. In the photosensor having the action of continuing the electrical conductivity when the voltage is continuously applied and continuing the information recording on the information recording medium, photocarriers are trapped between the electrode and the photoconductive layer. The energy barrier at the electrode interface is flattened by the carrier charges, and a photo-induced current amplification layer having a function of flowing a current due to the injected charges in addition to the photocurrent generated by the information exposure is characterized. Optical sensor to collect. 3. An optical sensor used for forming information on an information recording medium, which has a photoconductive layer on an electrode, is semiconductive, and can form information on the electrode by an electric field or a charge amount. It is used by arranging it facing the information recording medium in which various information recording layers are laminated, and a voltage is applied between the electrodes of the photosensor and the electrodes of the information recording medium in the state where information is exposed, or in the state where a voltage is applied. When information is exposed, information can be recorded on the information recording medium with an intensity that is amplified more than the current caused by the information exposure, and if voltage is continuously applied even after the information exposure is completed, the conductivity is maintained and the information continues. In an optical sensor having an action of continuing information recording on a recording medium,
Between the electrode and the photoconductive layer, the energy barrier at the electrode interface is flattened by the carrier charges captured by the charge traps generated by the photocarriers trapped and injected in addition to the photocurrent generated by the information exposure. An optical sensor having a photo-induced current amplification layer having a function of causing a current to flow due to an electric charge. 4. The photosensor according to claim 1, wherein the specific resistance of the electrode has a conductivity of 10 ⁶ Ω · cm or less. 5. The optical sensor according to claim 1, which is obtained by aging in a dark place having a relative humidity of 60% or less. 6. An optical sensor 10 is applied when a voltage is applied.
4. The optical sensor according to claim 1, wherein the passing current density in the unexposed portion is 10 ⁻⁴ to 10 ⁻⁷ A / cm ² when an electric field strength of ⁵ to 10 ⁶ V / cm is applied. . 7. The conductivity of the exposed portion increases more than the conductivity of the unexposed portion due to the exposure during voltage application, and the conductivity in the exposed portion remains unexposed while the voltage is applied even after the exposure is completed. The conductivity is maintained higher than the conductivity of No. 3, and the conductivity in the exposed portion is rapidly reduced after the voltage application is completed to become equal to the conductivity in the unexposed portion, and reusable quickly and repeatedly. Light sensor. 8. A thermostimulation current measurement, 40 to 150 ° C.
4. The photosensor according to claim 1, wherein a clear peak is observed in the range. 9. An information recording apparatus for recording optical information on an information recording medium by information exposure, wherein a gap is provided between the optical sensor according to claim 1 and the information recording medium having an information recording layer formed on an electrode. An information recording device characterized by being connected on the optical axis. 10. The information recording device according to claim 9, wherein the information recording layer comprises a liquid crystal phase and a resin phase. 11. The information recording layer comprises an ultraviolet curable resin, liquid crystal, and a surfactant.
The information recording device described in 0. 12. The liquid crystal material is a mixture of a smectic liquid crystal and a nematic liquid crystal, and the liquid crystal material is a mixture of the smectic liquid crystal and the nematic liquid crystal.
11. The information recording device according to item 11. 13. The resin phase constituting the information recording layer is composed of an ultraviolet curable resin, and the surface layer of the information recording layer is composed only of a skin layer of the ultraviolet curable resin. Information recording device described. 14. The information recording device according to claim 9, wherein the information recording layer has a memory property. 15. An optical sensor to 10 ⁵ to 10 ⁶ V / cm
The passing current density in the unexposed portion is 10 ⁻⁴ to 10 ⁻⁷ A / cm ² and the specific resistance of the information recording medium is 10 ¹⁰ to 10 ¹³ Ω · cm during the application time of the electric field strength of. The information recording device according to claim 9, which is characterized in that. 16. In an information recording device in which a photoconductive layer, a dielectric layer, an information recording layer, and an upper electrode are laminated in this order on the lower electrode, the photosensor unit comprising the lower electrode and the photoconductive layer is formed by the method of any one of claims 1 to 8. An information recording device comprising the optical sensor described in (1) above, wherein a voltage is applied between the lower electrode and the upper electrode to enable voltage application. 17. An information recording / reproducing method for recording optical information on an information recording medium by information exposure, according to claim 1.
The information recording medium having the information recording layer formed on the optical sensor and the electrode described in 1. is used, and at least one of the optical sensor and the information recording medium is a transparent electrode, and the optical sensor and the information recording medium are separated from each other by a gap. Are arranged opposite to each other on the optical axis, and information is recorded on the information recording medium by exposing the optical information while applying a voltage between both electrodes, and recorded on the information recording medium as visible information by transmitted light or reflected light. An information recording / reproducing method characterized by reproducing optical information. 18. An information recording layer in an information recording medium,
2. A liquid crystal phase and a resin phase.
7. The information recording / reproducing method described in 7. 19. The information recording layer of the information recording medium,
19. The information recording / reproducing method according to claim 17, which comprises an ultraviolet curable resin, a liquid crystal, and a surfactant. 20. The liquid crystal material is a mixture of a smectic liquid crystal and a nematic liquid crystal, and the liquid crystal material is a mixture of the smectic liquid crystal and the nematic liquid crystal.
19. The information recording / reproducing method described in 19. 21. The resin phase constituting the information recording layer is composed of an ultraviolet curable resin, and the surface layer of the information recording layer is composed only of a skin layer of the ultraviolet curable resin. Information recording and reproducing method described. 22. An information recording method for recording optical information on an information recording medium by information exposure, wherein the information recording medium comprises a photoconductive layer, a dielectric layer, an information recording layer, and a game electrode which are sequentially laminated on a lower electrode. An optical sensor part including a lower electrode and a photoconductive layer is formed of the optical sensor according to claim 1, wherein at least one of the lower electrode and the upper electrode is a transparent electrode, and a space between the lower electrode and the upper electrode. Information recording / reproducing characterized in that information is recorded on the information recording medium by exposing the optical information while applying a voltage to the information, and the optical information recorded on the information recording medium as visible information is reproduced by transmitted light or reflected light. Method. 23. The recorded optical information is read by a scanner having a CCD sensor, and an image is output by a sublimation transfer printer.
22. An information recording / reproducing method described in 22.