JPH0470844A - Photosensitive body and method for recording electrostatic information - Google Patents

Abstract

PURPOSE:To impart electric charges with information having arbitrary polarity to an information recording medium as well as to enhance the sensitivity and resolution of the medium by forming an electric charge generating layer with a specified bisazo compd. CONSTITUTION:A photosensitive body obtd. by successively laminating an electrically conductive layer 7, an electric charge transferring layer and an electric charge generating layer on a substrate 5 is placed opposite to an information recording medium 3 having a photoconductive layer 13 and an electric charge retaining layer 11, voltage is impressed between the photosensitive body 1 and the medium 3 and electrostatic information is recorded on the medium 3 by exposure. The electric charge generating layer is formed with a bisazo compd. represented by formula I, wherein each X is H, lower alkyl, lower alkoxy, nitro, sulfonic acid, hydroxyl, carboxyl or halogen, n is an integer of 0-3, in case of n>=2, X's may be different from each other, and each R is an optionally substd. cyclic hydrocarbon group, a heterocyclic group or alkyl. Light with information incident from the medium 3 side can directly form an image on the surface of the photosensitive body 1 and the information can be recorded with high resolution without blurring the image.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a photoreceptor and an electrostatic information recording method, and in particular, to improving the sensitivity and resolution of electrostatic information recording on an information recording medium, and to improving information recording. The present invention relates to an information recording medium and an electrostatic information recording method capable of imparting information charges of arbitrary polarity to the medium.

[Conventional technology]

Conventionally, silver halide photography is known as a high-sensitivity photographing technique. In this photography method, the photographed image goes through a developing process and is recorded on film, etc., and when reproducing information, a silver salt emulsion (
This is done by using a photographic paper (such as photographic paper) or by optically scanning a developed film and reproducing it on a cathode ray tube (hereinafter referred to as CRT).

In addition, a conductive layer is deposited on the photoconductive layer, the entire surface of the photoconductive layer is charged by corona charging in a dark place, and then exposed to strong light to make the photoconductive layer conductive in the exposed areas. By leaking and removing the charge, an electrostatic latent image is optically formed on the surface of the photoconductive layer, and a toner having a charge of the opposite polarity (or a charge of the same polarity) as the residual electrostatic charge is attached. There is an electrophotographic technology that develops the image using a process, but this is mainly used for copying and cannot be used for photography due to its low sensitivity. It is normal to develop toner immediately.

In addition, TV photography technology takes pictures with an image pickup tube, extracts the information obtained using an optical semiconductor as an electrical signal, outputs it as is to a CRT, or records it as a video using magnetic recording, etc., and displays it on the CRT at any time. There are methods such as outputting an image.

[Problem to be solved by the invention]

Silver halide photography is an excellent means of preserving images of subjects, but it requires a developing process to form silver halide images, and image reproduction involves complex optical processes such as hard copy and soft copy (CRT output). physical, electrical, or chemical treatment is required.

Although electrophotographic technology allows the electrostatic latent image to be visualized more easily and quickly than silver salt photography, the storage time of the latent image is extremely short, and developer dissociation properties, image quality, etc. are inferior to silver salt photography.

TV photographing technology requires line-sequential scanning in order to extract and record electrical image signals obtained by an image pickup tube. Line-sequential scanning is performed with an electron beam in the image pickup tube and with a magnetic head in video recording, but resolution depends on the number of scanning lines and is significantly worse than planar analog recording such as silver halide photography. .

Furthermore, TV imaging systems using solid-state imaging devices (CCDs, etc.), which have been developing in recent years, are essentially the same in terms of resolution.

Problems inherent in these technologies include complicated processing steps if the information recording is of high quality and high resolution, and lack of storage function or basic deterioration of image quality if the steps are simple.

The present inventor has developed a photoconductor consisting of a photoconductive layer on which a conductive layer is provided on the front surface, and an information recording medium consisting of a charge retention layer facing the photoconductor and provided with a conductive layer on the rear surface. An application was filed for an electrostatic information recording method in which an electrostatic latent image corresponding to an incident optical image is formed on an information recording medium by arranging it on the axis and exposing it while applying a voltage between both groove electrolytic layers (Patent application filed in 1983). .3-121
No. 592) However, the photoreceptor used in this electrostatic information recording method has certain problems in its ability to form electrostatic information on an information recording medium.

The present invention is intended to solve the above-mentioned problem U, and is particularly directed to a photoconductor that can improve the green sensitivity and resolution of electrostatic information to an information recording medium and can impart information charges of arbitrary polarity to the information recording medium. and to provide an electrostatic information recording method.

[Means to solve the problem]

The photoreceptor of the present invention includes a photoreceptor in which a conductive layer, a charge transport layer, and a charge generation layer are sequentially laminated on a substrate, and an information recording medium provided with a conductive layer and a charge retention layer in opposition to the photoreceptor. A photoreceptor used in an electrostatic information recording method in which electrostatic information is recorded on an information recording medium by exposing information while applying a voltage between the photoreceptor and an information recording medium, or by applying a voltage while exposing information. It is characterized in that the charge generation layer is made of a bisazo compound represented by the following formula (1).

Formula (1) (However, X in the formula may be the same or different selected from hydrogen, lower alkyl group, lower alkoxy group, nitro group, sulfonic acid group, hydroxyl group, carboxyl group, and halogen atom, and n is an integer of 0 to 3, and R is an optionally substituted hydrocarbon ring group, heterocyclic group, or alkyl group.

) Furthermore, the electrostatic information recording method of the present invention includes a photoreceptor having a conductive layer and a photoconductive layer provided on a substrate, and an information recording medium having a conductive layer and a charge retention layer provided opposite to the photoreceptor. Place the
In an electrostatic information recording method in which electrostatic information is recorded on an information recording medium by exposing information while applying a voltage between a photoreceptor and an information recording medium, or by applying a voltage while exposing information, the photoreceptor has a conductive layer. It is characterized by being a functionally separated photoreceptor in which a charge transport layer and a charge generation layer are sequentially laminated on top, or a single-layer photoreceptor in which a photoconductive layer having both a charge transport function and a charge generation function is provided on a conductive layer. shall be.

The photoreceptor in the present invention will be explained below.

The photoconductor of the present invention is a functionally separated photoconductor (laminated photoconductor).
Alternatively, it can be a single-layer photoreceptor.

First, the functionally separated photoreceptor will be explained.

Charge-generating materials easily absorb light but have the property of trapping light, and charge-transporting materials have good charge transport properties but poor light absorption properties. Therefore, it is a type in which a charge generation layer and a charge transport layer are laminated in order to separate the two and fully exhibit their respective characteristics.

Examples of substances forming the charge generation layer include azo, bisazo, trisazo, phthalocyanine, acidic xanthene dye, cyanine, styryl dye, pyrylium dye, perylene, methine, and a- 5
λ, azulenium salt system, squalium ring system, etc.

Among these, the bisazo compound represented by the above formula (I) is preferably used to form the charge generation layer in the functionally separated photoreceptor.

Regarding specific examples of bisazo compounds in formula (I),
Compound numbers 1 to 23 are exemplified below depending on the combination of each substituent in formula (1) above.

in particular, Among these, compounds represented by the following formula are preferably used.

2H5 Next, the charge transport material forming the charge transport layer is a material that has good transport properties for charges generated by the charge generation material, such as hydrazone type, pyrazoline type, PVK type, carbazole type, oxazole type, triazole type, etc. There are aromatic amine-based materials, amine-based materials, triphenylmethane-based materials, polycyclic aromatic compound materials, etc., and any material having hole-transporting properties or electron-transporting properties can be used.

2H5 Next, a method for laminating photoconductive layers will be explained.

The photoreceptor in the present invention includes a functionally separated type photoreceptor and a single-layer type photoreceptor.

First, as a lamination method for a functionally separated photoreceptor, a charge generating substance is dispersed in the form of fine particles (diameter of 5 x 1 m or less, preferably 3 μm or less, particularly 1 μm or less) in a suitable solvent together with an inder resin, etc. A charge-generating layer is formed by coating and drying on the conductive layer, and then a charge-transporting material is dissolved or dispersed in an appropriate solvent and coated on the charge-generating layer to form a charge-transporting layer. As a coating method, blade coating method, dipping method, spinner coating method, flexo printing method, etc. can be used.
The charge generation layer has a film thickness of 0.1 μm to 110 A1.
The thickness of the charge transport layer is preferably 1 μm to 50 μm.

In addition to the organic photoreceptor, a selenium photoreceptor can also be used as the functionally separated photoreceptor.

As a selenium photoreceptor, elemental selenium is used as a charge transport layer material, a-selenium-tellurium, arsenic selenium compound (As
2Ses) or an arsenic selenium compound + Te as the material for the charge generation layer, which is either formed on the conductive layer by vapor deposition or sputtering, or a charge injection blocking layer (S1
02,^1203, SiC, Si3N4 is formed on the conductive layer by vapor deposition, sputtering, glow discharge method, etc.). In this case, the thickness of the charge generation layer is preferably 0.03 μm to 3 μm, and the thickness of the charge transport layer is preferably 1 μm to 100 μm.

Next, a single layer photoreceptor will be explained.

Organic single-layer photoreceptors are formed from a mixture of a charge generating material and a charge transporting material.

Charge-generating substances are substances that easily generate charges by absorbing light, such as azo pigments, bisazo pigments, trisazo pigments, phthalocyanine pigments, perylene pigments, pyrylium dyes, cyanine dyes, and methine dyes. system is used.

In addition, the charge transport substance is a substance that has good transport properties for ionized charges, such as hydrazone type, pyrazoline type, polyvinylcarbazole type, carbazole type, stilbene type, anthracene type, naphthalene type, tridiphenylmethane type, azine type, and amine type. There are various types such as aromatic amine type and aromatic amine type.

The photoconductive layer in this single-layer photoreceptor may be formed by forming a complex with a charge-generating substance and a charge-transporting substance to form a charge-transfer complex.

Normally, photoreceptors have photosensitivity determined by the light absorption properties of the charge-generating substance, but when a charge-generating substance and a charge-transporting substance are mixed to form a complex, the light absorption properties change; for example, polyvinylcarbazole (PVK) Trinitrofluorenone (T N F ) is only felt at wavelengths around 400 nm, but PVK-TNF complexes are only felt at wavelengths around 650 nm.
You will be able to feel up to the m wavelength range.

As a coating method, a blade coating method, a dipping method, a spinner coating method, a flexographic printing method, etc. can be used. The thickness of such a single-layer photoreceptor is preferably 10 to 50 μm.

In addition to the organic photoreceptor, an a-selenium or a-silicon photoreceptor can also be used in the present invention. The a-silicon photoreceptor is made by doping silicon with impurities (B, AI, Ga, In, TI, etc.),
P-type (hole transport type), silicon with impurities (
P, Ag.

A material doped with Sb, Bi, etc.) to become N type (electron transport type) can be used.

The formation method involves introducing silane gas and impurity gas together with hydrogen gas into a low vacuum of 10-2 to I Torr.
), it can be formed by depositing it on a conductive layer substrate that is heated or not heated by glow discharge, it can be formed by a thermochemical reaction on a simply heated conductive layer substrate, or it can be formed by vapor deposition or sputtering of a solid raw material. It can be used as a single layer or in a laminated form. The film thickness is 1 to 50 μm. In this case, it is preferable to provide a charge injection prevention layer on the surface of the conductive layer. As the charge injection prevention layer, a-SjsN< layer, a-3iC layer, 5102 layer, AIa layer is formed on one or both of the conductive layer and the top layer (surface layer) of the photoreceptor by glow discharge, vapor deposition, sputtering, etc.
It is preferable to provide an insulating layer such as the 03 layer. If this insulating layer is made too thick, no current will flow when exposed to light, so it must be at least 1000 Å or less, and in consideration of ease of fabrication, it is preferably about 400 to 500 A. In addition, as a charge injection prevention layer, it is preferable to provide a charge transport layer on the conductive layer substrate using a rectifying effect, which has a charge transport ability with a polarity opposite to that of the conductive layer.If the conductive layer is negative, a hole transport layer is preferably provided. , if the conductive layer is positive, an electron transport layer is provided.

For example, a-5t:H(n+
) has improved hole transport properties, provides a rectifying effect, and functions as a charge injection prevention layer.

In the case of organic photoreceptors, silicone resins, styrene-butadiene copolymer resins, epoxy resins, acrylic resins, saturated or unsaturated polyester resins, polycarbonate resins, polyvinyl acetal resins, phenol resins, polymethyl methacrylates are used as binders. (P
It is preferable to add 01 to 10 parts of MMA) resin, melamine resin, polyimide resin, etc. to 1 part each of the charge generating material and the charge generating material.

The material of the conductive layer in the photoreceptor has a specific resistance value of 106
It is not limited as long as it is 0.cIT1 or less, and transparent or semi-transparent conductive layers such as inorganic metal conductive films, inorganic metal oxide conductive films, organic conductive films such as quaternary ammonium salts, and light reflective conductive films. , conductive plates can be used.

In the present invention, the sensitivity of information recording on an information recording medium can be increased by making the conductive layer in the photoreceptor particularly light reflective. For example, a conductive material such as aluminum, gold, platinum, zinc, indium, tin, silver, copper, nickel, or chromium is formed on a support by a method such as vapor deposition or sputtering, or a metal plate having a supporting function is formed. can be used.

The thickness of the conductive layer needs to be changed depending on the electrical properties of the material constituting the photoreceptor conductive layer and the applied voltage when recording information.
There are 3000 people.

There are no particular restrictions on the thickness or material of the support for the photoreceptor as long as it has a certain level of strength to support the photoreceptor, such as a flexible plastic film with a thickness of about 100 μm or glass. , a rigid body such as a plastic sheet is used, but if the conductive layer is a transparent conductive layer, it is preferable to use a rigid body with a light-reflecting function. It is not necessary in cases such as a board.

The photoreceptor used in the present invention has been described above. Next, the information recording medium on which electrostatic information is recorded by the photoreceptor will be described.

An information recording medium is formed by laminating a charge retention layer or a recording layer capable of visualizing electrostatic information on a conductive layer. The charge retention layer is made of a highly insulating polymeric material in order to suppress the movement of charges, and is required to have an insulating property of 0.14 Ω·cm or more in terms of specific resistance. Furthermore, it is necessary that the glass transition temperature of the polymeric material constituting the charge retention layer be higher than the operating environment temperature.

As such polymeric materials, thermoplastic resins, energy beam curing resins such as thermosetting resins, ultraviolet curing resins, electron beam curing resins, engineering plastics, etc. can be used. For example, fluororesins such as polytetrafluoroethylene,
Fluorinated ethylene propylene, tetrafluoroethylene
Using perfluoroalkyl vinyl ether copolymers, their dispersion type or modified type (coating type), polyether ether ketone resin, polyparaxylylene, etc., it is dissolved in a solvent and coated on the conductive layer. Film thickness of 1 μm to 1 μm by vapor deposition, etc.
The layer is formed to a film thickness of 00 μm.

Further, as a recording layer capable of visualizing electrostatic information, a frost-forming material made of a thermoplastic resin or a material having an electro-optic effect such as liquid crystal can be used.

Since the information recording medium of the present invention requires light transparency when exposed from the information recording medium side, transparency is required for the conductive layer and the support. As such a conductive layer, a transparent conductive layer forming material described for the above-mentioned photoreceptor is used. For example, if the information light is visible light (400 nm to 700 nm), indium oxide-t& (In , O, -3n02) (I T○
) films, tin oxide films, etc., the number of workers is about 100 to 3000, and transparent conductive layers such as those coated by sputtering, vapor deposition, or by making ink with their fine powders together with a binder, Au, AI, Ag, Ni5Cr, etc. evaporation, etc.
Alternatively, a semi-transparent conductive layer prepared by sputtering, an organic transparent conductive layer coated with tetracyanoquinodimethane (TCNQ), polyacetylene, etc. are used.

The above conductive layer material can also be used when the information light is infrared light (700 nm or more), but in some cases, a colored visible light absorbing conductive layer can also be used to cut visible light. Furthermore, when the information light is ultraviolet light (below 40 IJnmu), the above conductive layer materials can basically be used, but conductive layer substrate materials that absorb ultraviolet light (such as polymeric materials, soda glass, etc.) This is not preferred, but materials that transmit ultraviolet light, such as quartz glass, are preferred.

As a support for an information recording medium, as long as it has a certain degree of strength that can support the information recording medium,
There are no particular restrictions on the thickness or material; for example, a flexible plastic film with a thickness of about 100 μm, glass,
A rigid body such as a plastic sheet is used, particularly preferably transparent.

Further, it is preferable to form an antireflection film on the information light incident surface of the information recording medium. This antireflection film can be formed by a single layer or a stack of inorganic materials such as magnesium fluoride, zinc sulfide, and titanium oxide by vapor deposition, sputtering, or the like.

In the organophotoreceptor and information recording medium of the present invention,
By providing a charge injection prevention layer between a conductive layer and a photoconductive layer, or between a charge retention layer, an increase in dark current can be prevented.

There are two types of charge injection prevention layers: one that utilizes the so-called non-ring effect and one that utilizes a rectification effect.

First, in the case of a device that utilizes the so-called non-ring effect, when only voltage is applied, this charge injection prevention layer prevents the photoconductive layer.
Alternatively, no current flows to the surface of the insulating layer, but when light is incident, one of the charges (electrons or holes) generated in the photoconductive layer is present in the charge injection prevention layer corresponding to the incident area. When a high electric field is applied, a tunnel effect occurs and current flows through the charge injection prevention layer.

Such a charge injection prevention layer is formed of a single layer such as an inorganic insulating film, an organic insulating polymer film, an insulating monomolecular film, or a stack of these films.
203, B1n5, B+Js, CdS, CaO, C
eO2, Cr2O3, (:o[l, Ge0z,)l
fO,, Pe2ts, LazO+, MgO, MnO2
, NdJ3, NI]zOs, PbO1Sb20s,
5102.5ea2, TawDs, TiO2, WO,
, ν2υ5, Y, 05, Y, 00, ZrL, 13a7
io+, ^1203, B12TIO5, CaO-5r
O, Can-Y2O3, Cr-5iO1LiTaOs,
PbT+Os, PbZr0a, Zr0=-Co, 2r
L-5QL, ^IN 5all, NbN, 5i3L
, TaN, TiN, , VN, ZrN, S
iC, TiC.

The ridges, ^1-Cs, etc. are formed by glow discharge, vapor deposition, sputtering, etc. The thickness of this layer is determined depending on the material used, taking into account insulating properties to prevent charge injection and tunneling effects.

Next, a charge injection prevention layer using a rectification effect is formed by providing a charge transport layer having a charge transport ability with a polarity opposite to that of the conductive layer substrate using a rectification effect. Such a charge injection prevention layer is formed of an inorganic photoconductive layer, an organic photoconductive layer, or an organic-inorganic composite photoconductive layer, and its film thickness is 0.
．． It is about 1 to 10 μm. Specifically, when the conductive layer is negative, an amorphous silicon photoconductive layer doped with 8% A1, Ga, In, etc., an amorphous selenium photoconductive layer, a polyvinylcarbazole photoconductive layer, or oxadiazole, pyrazoline, polyvinylcarbazole, etc. , stilbene, anthracene, naphthalene, tridiphenylmethane, triphenylmethane, azine, amine, aromatic amine, etc., dispersed in a resin. When the conductive layer is positive, P, N, As, An amorphous silicon photoconductive layer doped with Sb, Bi, etc., a ZnO photoconductive layer, a polyvinylcarbazole-trinitrofluorenone organic photoconductive layer, etc. are formed by methods such as glow discharge, vapor deposition, sputtering, CVD, and coating.

Next, the electrostatic information recording method of the present invention will be explained with reference to FIG. In the figure, 1 is a photoreceptor, 3 is an information recording medium, 7 is a photoreceptor conductive layer, 9 is a photosensitive layer, 11 is a charge retention layer or information recording layer, 13 is a conductive layer, 15 is a support, and 17 is a power source. be.

To record electrostatic information on an information recording medium, first see Figure 2 (
As shown in a), the information recording medium 3 is set on the photoreceptor 1 with gaps of 1 μm to 100 μm,
As shown in the same figure (b), the conductive layer 7.13 is
Apply voltage to open.

In a dark place, since the photosensitive layer 9 is a high-resistance material, no change occurs between the conductive layers. When light is incident from the information recording medium 3 side, photocarriers are generated in the charge generation layer of the photosensitive layer where the light is incident, a discharge occurs between the charge retention layer 11, and charges are accumulated in the charge retention layer 11. be done.

Since the electrostatic information recording method of the present invention uses a photoreceptor in which a charge-generating substance is arranged on the outermost layer of the photoreceptor facing the information recording medium, information light when incident from the information recording medium side is This enables direct image formation on a charge-generating substance, and enables high-resolution accumulated charges to be applied to an information recording medium without causing image blurring. In addition, by making the conductive layer or support of the photosensitive member light-reflective, the reflected light of the information light can also be used, so that information can be recorded with high sensitivity.

In addition, since the charge generation layer is on the outermost surface, blurring of the charge image due to the diffusion of generated carriers in the charge transport layer does not occur, and high-resolution electrostatic information is formed on the information recording medium side. be able to.

Furthermore, when applying a voltage between the photoconductor electrode and the information recording medium electrode, if the photoconductive layer of the photoconductor has hole transport properties, such as an organic photoconductor or a selenium photoconductor, the first As shown in the figure, it is necessary to make the photoreceptor electrode side a negative electrode, thereby giving the information recording medium a negative accumulated charge.

That is, in the case where the photoreceptor has a structure different from that of the present invention, for example, in a photoreceptor in which a charge generation layer and a charge transport layer having hole transport properties are sequentially arranged on a conductive layer, a voltage can be applied using the photoreceptor electrode as a positive electrode. In contrast, in the electrostatic information recording method of the present invention, a charge-generating substance is placed on the surface layer of the photoreceptor, so that information is recorded on the information recording medium. The recording medium is capable of accumulating negative information charges.

Depending on the material forming the recording layer of the information recording medium, the retention properties may differ depending on the polarity of the accumulated charge. For example, if the information recording medium has a recording layer made of fluororesin, it may have negative charge retention characteristics. is better than positive ones, but
In such cases, the electrostatic information recording method of the present invention can be suitable.

It goes without saying that the voltage applied between the photoreceptor and the information recording medium is generally determined in consideration of the charge transport properties of the photosensitive layer.

In this way, when the exposure is completed, the voltage is turned off as shown in the figure (C), and then the information recording medium 3 is taken out as shown in the figure (d), thereby completing the formation of the electrostatic latent image. do. In order to retain the charges accumulated in the information recording medium for a long period of time, an insulating protective film may be laminated on the charge retention layer.

Information input methods in the electrostatic information recording method include a method using an electrostatic camera and a recording method using a laser. First, electrostatic cameras consist of a recording member consisting of a photoreceptor and an information recording medium instead of the photographic film used in ordinary cameras, and a voltage is applied to both groove conductive layers, allowing light to be emitted according to the incident light. The conductive layer is made conductive, and charges are accumulated on the charge retention layer according to the amount of incident light.A mechanical nyatta or an electric nyatta can be used.

In addition, optical information can be converted to R using prisms and color filters.
, G, and B light components, extracted as parallel light, and R,
Color photography can also be performed by forming one frame with three sets of information recording media separated into G and B, or by arranging R1GSB images on one plane and making one frame with one set.

For recording methods using lasers, the light sources include argon laser (514,488 nm), helium-neon laser (633 nm), and semiconductor laser (780 nm).
nm, 810 nm, etc.), and is used for information signals, character signals,
Laser exposure corresponding to code signals and line drawing signals is performed by scanning. Analog recording such as information is performed by modulating the light intensity of the laser, and digital recording such as characters, codes, and line drawings is performed by controlling the laser light. Further, halftone dots are formed in information by applying dot generator 〇N-0FF control to laser light. Note that the spectral characteristics of the photoconductive layer in the photoreceptor do not need to be panchromatic, but only need to be sensitive to the wavelength of the laser light source.

Next, the electrostatic information recorded on the information recording medium may be reproduced by reading its surface potential, or it may be visualized by toner development or liquid crystal display; for example, by reading the potential. Explain how to play.

FIG. 2 is a diagram showing a method for reading the potential of electrostatic information stored in an information recording medium, and the same numbers as in FIG. 1 indicate the same contents. In the figure, 3 is an information recording medium, 21 is a potential reading section, 23 is a detection conductive layer, 25 is a guard conductive layer, 27 is a capacitor, and 29 is a voltmeter.

When the potential reading section 21 is placed to face the charge accumulation surface of the information recording medium 3, an electric field generated by the charges accumulated on the charge retention layer 11 of the information recording medium 3 acts on the detection conductive layer 23, and an electric field is generated on the detection conductive layer surface. An induced charge equal to the charge on the information recording medium is generated. Since the capacitor 27 is charged with an equal amount of charge of opposite polarity to this induced charge, a potential difference corresponding to the accumulated charge is generated between the conductive layers of the capacitor, and this value is measured by a voltmeter.
9, the potential of the charge carrier can be determined. Then, by scanning the surface of the information recording medium with the potential reading section 21, the electrostatic latent image can be output as an electrical signal. Note that if only the detection conductive layer 23 is used, an electric field (line of electric force) due to charges in a wider range than the area facing the detection conductive layer of the information recording medium will act, resulting in a decrease in resolution.
A grounded guard conductive layer 25 may be arranged around the detection conductive layer. As a result, the lines of electric force are oriented perpendicularly to the surface, so that the lines of electric force only act on the area facing the detection conductive layer 23, and the potential of the area approximately equal to the area of the detection conductive layer 23 is can be read. The accuracy and resolution of potential reading vary greatly depending on the shape and size of the detection conductive layer and guard conductive layer, as well as the distance from the information recording medium, so it is necessary to determine the optimum conditions and design according to the required performance. be.

In addition, an information recording medium that has stored information in the form of electrostatic charges is irradiated with laser light, etc., and the information is transmitted using the polarization phenomenon caused by electrostatic charges through an element made of liquid crystal or electro-optic crystal that has an electro-optic effect. May be played. For example, an electro-optic crystal may be placed in the optical path, and as such an electro-optic crystal, one having an electro-optic effect such as lithium niobate (LiNb05), barium titanate, or lithium tantalate (L+Ta03) may be used. I can do it.

FIG. 3 is a diagram showing a schematic configuration of the electrostatic information reproducing method, in which 31 is a potential reading device, 33 is an amplifier, and 35 is a C
RT, 37 is a printer.

In the figure, a potential reading device 31 detects the charge potential, and an amplifier 33 amplifies the detected output, which can be displayed on a CRT 35 and printed out using a printer 37. In this case, it is possible to arbitrarily select and output the part to be read at any time, and it is also possible to reproduce it repeatedly.

Furthermore, since the electrostatic latent image is obtained as an electrical signal, it can also be used for recording on other recording media, etc., if necessary.

[Action and effect of invention]

On the electrostatic information recording layer of the present invention, information charges corresponding to the exposure are accumulated in the information recording medium through information exposure using a photoreceptor having a layer having a charge generation function on the surface of the photoreceptor. Therefore, the information light incident from the information recording medium side can be directly imaged on the charge generation material layer on the outermost surface of the photoreceptor, without causing image blurring, and without causing carrier diffusion in the charge transport layer. Since there is no influence of , high resolution information recording can be performed. Furthermore, by making the conductive layer or support of the photoreceptor light-reflective, it is possible to utilize the reflected light of the information light, thereby making it possible to record information with high sensitivity.

Furthermore, information charges of arbitrary polarity can be applied to the electrostatic information recording layer, and depending on the material for forming the charge retention layer, it may be particularly suitable when the retention performance differs depending on the polarity of the information charge. can.

Examples will be described below.

[Example 1] 15 parts by weight of p-diethylaminobenzaldehyde-N-phenyl-benzylhydrazone and 10 parts by weight of polycarbonate resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name: Nipiron S-100) were used as charge transport materials, and zig-o-lomethane: l
, 1. 2-) Prepare a solution with a solid content of 178% using a mixed solvent of 4:6 dichloroethane, and apply this solution to an IT○ transparent electrode (wN thickness of about 500, resistance value 80Ω).
/SQ,) on a glass substrate with a blade coater with a gap thickness of 2 mils and heated at 80 °C for 2
After drying for a while, a charge transport layer having a thickness of 0 μm was formed.

Next, a solution was prepared in which 3 parts by weight of bisazo pigment of Compound No. 2 and 1 part by weight of polyvinyl acetal resin were adjusted to a solid content of 2% with a mixed solvent of dioxane and hexane (1.1 parts) as a charge generating material. , coated on the charge transport layer using a 2 mil gap blade coater,
A photoreceptor was prepared by drying at 100° C. for 1 hour to form a charge generation layer of 0.3 μm.

On the other hand, 50% xylene solution of methyl-phenyl silicone varnish (manufactured by Toshin Ricoh Co., Ltd.: trade name Ko 5R-144)
was added with n-butyl alcohol at a weight ratio of 1=1, and a diluted curing catalyst (manufactured by Toshin Silicone Co., Ltd.: trade name CR-
12) was added in an amount of 2% by weight to the above xylene solution, thoroughly stirred, and then filtered through a mesh. This filtrate was transferred to an IT○ transparent electrode (film thickness approximately 500 mm, resistance value 80 Ω/sq.)
The coating was applied onto the electrode of a glass substrate having a spin code method by rotating at 400 rpm for 2 seconds and then slowing down the rotation for 30 seconds.

Then, heat it in an oven at 150°C for 1 hour to dry it.
By curing, a 6 μm thick methylphenyl silicone layer was formed on the ITO electrode to produce an information recording medium.

The photoreceptor and the information recording medium prepared as described in 2 above were placed facing each other and grounded using a 10 μm thick polyester film as a spacer. Next, a DC voltage of 750 V was applied between the two electrodes, with the photoreceptor electrode as the negative electrode and the information recording medium electrode as the positive electrode, and at the same time a grayscale (step wedge: Fuji Photo Film Co., Ltd.)
(manufactured by), 30 μW/cm2 (color temperature 3200K)
) was projected for 0.1 seconds from the information recording medium side, and the potential was measured using a non-contact potential reader (Trek Model 344). An image was formed on the information recording medium.

Further, even when this information recording medium was left in an oven at 60° C. for one month, the electrostatic latent image hardly attenuated.

Further, when R, G, and B filters were inserted into the projection exposure optical path and grayscale exposure was performed, electrostatic latent images corresponding to the RSG and B spectral lights were formed.

Also, when exposed using a resolution chart formed by the photomask method, 66 μm lines and spaces were 1°
1, resolved electrostatic information was obtained.

[Example 2] Information was recorded in the same manner as in Example 1 except that the gray scale and resolution chart were used and the information exposure was performed from the photoreceptor side. Although the sensitivity due to B spectrum light decreased slightly,
As in Example 1, the lines and spaces of 6° and 6 μm are 1:
It was resolved in 1.

[Example 3] Instead of the ITO electrode as the conductive layer in the photoreceptor in Example 1, a light-reflective conductive layer was made by laminating aluminum to a film thickness of 1000 mm on a glass substrate by vacuum evaporation. A photoreceptor was produced in the same manner as in Example 1, except for using the following.

On the other hand, an ITO transparent conductive layer (resistance value of about I KΩ/sq) was formed on one side of a 12.5 μm thick FEP film (hexafluoropropylene-tetrafluoroethylene copolymer: manufactured by DuPont) by sputtering, Furthermore, an information recording medium was produced by adhering the conductive layer side onto a glass substrate having a thickness of 1 mm using an adhesive.

The photoconductor and information recording medium thus prepared were exposed to information in the same manner as in Example 1, and the potential was measured using a surface electrometer, which corresponded to gray scale (step wedge: manufactured by Fuji Photo Film Co., Ltd.). It was found that an electrostatic latent image with a negative charge was formed on the information recording medium, and information charges could be obtained at a lower exposure amount than in the method of Example 1.

In this information recording medium as well, the electrostatic latent image hardly attenuated even if it was left in an oven at 60° C. for one month.

[Comparative Example 1] In Example 1, the stacking order of the charge generation layer and the charge transport layer was changed, and the charge generation layer was first placed on the conductive layer, and the charge transport layer was placed on the charge generation layer using the same lamination method as in Example 1. A photoreceptor was produced by laminating the layers.

This photoreceptor and the information recording medium produced and used in Example 3 were placed facing each other and grounded using a 10 μm thick polyester film as a spacer. Next, a DC voltage of 750 cm was applied between the two electrodes, with the photoreceptor electrode being the positive electrode and the information recording medium electrode being the negative electrode, and at the same time,
Bracekel (Step Wedge: Fuji Photo Film [
Co., Ltd.) through 30 uW/cm2 (color temperature 320
0K) light from the information recording medium side. Projection exposure was carried out for 1 second, and measurement using a surface electrometer revealed that a positively charged electrostatic latent image corresponding to the brace was formed on the information recording medium.

However, if this information recording medium is left in an oven at 60°C for one month, the electrostatic latent image will attenuate and a potential corresponding to the gray scale cannot be observed. It was found that the retention characteristics of electrostatic information were not good.

[Comparative Example 2] Same as Comparative Example except that instead of the ITO electrode which is the conductive layer in the photoreceptor in Comparative Example 1, a light reflective conductive layer was made by laminating aluminum electrodes with a thickness of 1000 mm. A photoreceptor was produced.

Using this photoreceptor and the information recording medium produced and used in Example 1, electrostatic information recording was performed in the same manner as in Comparative Example 1.

As a result, a positively charged electrostatic latent image corresponding to the gray scale was formed on the information recording medium, but when R, G, and B filters were inserted into the projection exposure optical path and the gray scale was exposed, charge transport was detected. Since the layer was yellow, the blue sensitivity was lowered, and an electrostatic latent image corresponding to the gray scale could not be formed when exposed to B spectrum light.

[Example 3] Poly-N-vinylcarbazole (manufactured by Anan Koryo ■) Log
, 2.4.7-) A mixed solution containing 10 g of linitrofluorenone, polyester resin (binder: manufactured by Toyobo ■, trade name Vylon 200), and 9 g of tetrahydrofuran was prepared in a dark place, and an ITO transparent electrode ( Film thickness approximately 500
A glass substrate (1
mm thickness) on the polar surface using a doctor blade, and
A photoreceptor having a photoconductive layer with a film thickness of about 10 μm was prepared by drying with ventilation at 0°C for 1 hour, and then drying for 1 hour to completely dry the photoreceptor.
Naturally dried for several days.

This single-layer photoconductor and the information recording medium produced and used in Example I were prepared in the same manner as in Example 1, except that the photoconductor electrode side was positive and the information recording medium electrode side was negative. As a result of information recording, the same results as in Example 1 were obtained.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the electrostatic information recording method of the present invention, FIG. 2 is a diagram showing an example of a DC amplification type potential reading method, and FIG. 3 is a diagram showing a schematic configuration for reproducing electrostatic information. It is a diagram. In the figure, 1 is a photoreceptor, 3 is an information recording medium, 5 is a support, 7 is a conductive layer, 9 is a photoconductive layer, 11 is a charge retention layer, 13 is a conductive layer, 15 is a support, and 17 is a power source. . Applicant Dainippon Printing Co., Ltd. Agent Patent attorney (1) Number (7 others) Figure 1 (b) (C) (CI)

Claims (5)

[Claims] (1) A photoreceptor in which a conductive layer, a charge transport layer, and a charge generation layer are sequentially laminated on a substrate, and an information recording medium provided with a conductive layer and a charge retention layer facing the photoreceptor are arranged, and the photoreceptor is In a photoconductor used in an electrostatic information recording method in which electrostatic information is recorded on an information recording medium by exposing information while applying a voltage between the information recording medium and the information recording medium, or by applying a voltage while exposing the information, a charge generation layer is used. A photoreceptor comprising a bisazo compound represented by the following formula (I). Formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, X in the formula is selected from hydrogen, lower alkyl group, lower alkoxy group, nitro group, sulfonic acid group, hydroxyl group, carboxyl group, and halogen atom) may be the same or different, n is an integer of 0 to 3, and R is an optionally substituted hydrocarbon cyclic group, heterocyclic group, or alkyl group.) (2) The photoreceptor according to claim 1, wherein the substrate or conductive layer of the photoreceptor is light reflective, and the exposure method is performed from the information recording medium side. (3) A photoconductor provided with a conductive layer and a photoconductive layer on a substrate, and an information recording medium provided with a conductive layer and a charge retention layer facing the photoconductor, the photoconductor and the information recording medium In an electrostatic information recording method in which electrostatic information is recorded on an information recording medium by exposing information while applying a voltage between them or by applying a voltage while exposing information, the photoreceptor has a charge transport layer on a conductive layer; A functionally separated photoreceptor with charge generation layers laminated in sequence,
Alternatively, an electrostatic information recording method characterized in that the photoreceptor is a single-layer photoconductor, in which a photoconductive layer having both a charge transport function and a charge generation function is provided on a conductive layer. (4) The electrostatic information recording method according to claim 3, wherein the charge generation layer in the functionally separated photoreceptor is made of a bisazo compound represented by the following formula (I). Formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, X in the formula is selected from hydrogen, lower alkyl group, lower alkoxy group, nitro group, sulfonic acid group, hydroxyl group, carboxyl group, and halogen atom) may be the same or different, n is an integer of 0 to 3, and R is an optionally substituted hydrocarbon cyclic group, heterocyclic group, or alkyl group.) (5) The electrostatic information recording method according to claim 3 or 4, wherein the substrate or conductive layer of the photoreceptor is light reflective, and the exposure method is performed from the information recording medium side.