JPH0683244A - Electrophotographic method - Google Patents

Abstract

PURPOSE:To perform trial printing in terms of density, alignment, etc., so that exposure condition can be adjusted by performing consecutive copying in a printing mode by means of a consecutive copying system in addition to a copying mode by means of a Carlson system. CONSTITUTION:The consecutive copying system is constituted of an image storing process for storing image information on an image holding member 10 and a consecutive copying process for performing copying by using the image holding member 10 on which the image information is stored. First, as to the image storing process storing the image information, a corona charger 60 is relatively moved with respect to the image holding member 10 so that the surface is negatively electrostatically charged. Next, image exposure is performed. Thus, positive charge is injected in a thermosoftened layer from a charge generating layer 3, transferred in the layer, and neutralizes the negative charge of conductive particles 5 at a part illuminated by light. On the other hand, the negative charge remains on the conductive particles 5 at the part which is not illuminated by the light. Consequently, the trial printing can be performed before performing the consecutive copying and the exposure condition can be adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic method using an image holding member in which image information is stored by moving conductive particles in a heat softening layer containing a heat softening resin.

[0002]

2. Description of the Related Art In the conventional electrophotographic copying method, the surface of an electrophotographic photosensitive member is uniformly charged, then imagewise exposure is performed to attenuate the surface potential in an imagewise manner, and then toner development is performed. The Carlson method of transferring to paper is widely applied as a general method. However, in this method, each time one image is copied, exposure must be performed once. Therefore, high-speed copying complicates the device,
There was a problem of increasing the size.

In order to improve this point, the present inventor previously disclosed in Japanese Patent Application No. 3-69442 that image information is stored in an image holding member in which conductive particles are embedded near the surface of the heat-softening layer. We have proposed an image-holding member that can make a large number of continuous copies with only one image exposure, and an electrophotographic method using the image-holding member.

[0004]

The electrophotographic method proposed by the present inventors is very suitable for continuously copying a large number of sheets, but the image holding member is discarded after copying. However, it is not suitable when a large number of copies are not required, for example, when one or two copies need to be stretched. Therefore, in order to copy a small number of sheets, it is necessary to separately make a copy using an ordinary electrophotographic copying machine. Further, when a large number of copies are required, it is desirable to perform so-called off-printing for density, position adjustment, etc. before continuous copying. Since the image information is stored by one image exposure, there is an inconvenience in use that adjustment cannot be performed by trial printing. The present invention has been made in view of the above inconvenience. That is, it is an object of the present invention to provide an electrophotographic method capable of trial printing, and in which even if a small number of sheets are copied, the image holding member is not discarded.

[0005]

The electrophotographic method of the present invention comprises:
A conductive layer formed by sequentially stacking at least a charge generation layer and a heat-softening layer made of a charge-transporting substance and a heat-softening resin on the conductive surface of a substrate, and embedding conductive particles near the surface of the heat-softening layer. Using an image holding member provided with a conductive particle layer, and a copy image by the Carlson system having at least steps including charging, image exposure, toner development, transfer to paper, and cleaning for the image holding member. , Or subsequently, the image holding member is negatively charged to accumulate charges in the conductive particles, and then image exposure corresponding to the image information is performed to eliminate the charges of the conductive particles in the exposed portion. After that, the heat-softening layer is heated to a temperature equal to or higher than the softening point of the heat-softening resin, the conductive fine particles in which electric charges are accumulated are moved in the heat-softening layer, and an image storing step of storing image information, And, the image holding member, charging, toner development, transfer onto paper, and the continuous copying mode having a continuous copying process comprising the cleaning and forming a copied image.

The present invention will be described in detail below. First, the image holding member used in the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of an image holding member of the present invention. An image holding member 10 has a conductive layer 2 formed on a substrate 1 and a charge generation layer 3 provided thereon. Furthermore, a heat-softening layer 4 made of a charge-transporting substance and a heat-softening resin which is softened by heat is further provided thereon.
Conductive particles 5 are embedded near the surface of the thermal softening layer 4 to form a conductive particle layer.

In the image holding member of the present invention, examples of the substrate include plastic film, paper, metal foil,
Any material such as glass can be used as long as it can be used in the electrophotographic photoreceptor. The shape is not particularly limited, and any shape can be used.

The substrate must have at least a conductive surface. The conductive surface may be formed by providing a conductive layer. The conductive layer may be made of any material as long as the charge flows freely. For example, a metal film is formed by a method such as a vapor deposition method, a sputtering method, a plasma CVD method, a plating method, or a metal or a metal having a low resistance is used. A conductive paint in which conductive particles such as oxides are dispersed in resin may be applied. Also, if the substrate is conductive, it is not necessary to form a conductive layer. An undercoat layer may be provided on the conductive surface in order to improve adhesiveness, chargeability, image quality, and the like.

The charge generation layer provided on the conductive surface of the substrate is the same as the charge generation layer used in a normal function-separated electrophotographic photoreceptor. That is,
As the charge generating material, a phthalocyanine pigment such as metal or metal-free phthalocyanine, a squarylium compound, an azurenium compound, a perylene pigment, an indigo pigment, a quinacridone pigment, anthanthrone, a brominated anthanthrone, pyranthrone, a polycyclic quinone such as flavanthrone,
A cyanine dye, a xanthene dye, a charge transfer complex composed of poly-N-vinylcarbazole and trinitrofluorenone, a eutectic complex composed of a pyrylium dye and a polycarbonate resin, and the like are used as a binder resin and optionally a charge transporter. It may be formed by dispersing and coating the material. Further, a film formed by vapor-depositing the charge generating material, a vapor-deposited film of amorphous silicon, or the like is also effective. Furthermore, it is also possible to use a titanyl phthalocyanine or bisazo pigment having a specific crystal structure which has been developed in recent years. The thickness of the charge generation layer is usually 0.1 to 2
It is set in the range of μm.

As the charge-transporting substance used in the heat-softening layer, any substance can be used as long as it is used in the charge-transporting layer in the electrophotographic photoreceptor. For example, polycyclic aromatic compounds such as anthracene, pyrene, and phenanthrene, compounds having a nitrogen-containing heterocycle such as indole, carbazole, and imidazole, pyrazoline compounds, hydrazone compounds, triphenylmethane compounds, triphenylamine compounds, stilbene compounds, benzidine Examples include compounds.

As the thermosoftening resin, a glass transition point (T
A thermoplastic resin having a g) of 30 to 90 ° C. and a viscosity at a temperature of Tg or higher of 10 ² to 10 ⁶ poise is preferably used. For example, polyethylene, vinyl chloride resin, polypropylene, styrene resin, ABS resin, polyvinyl alcohol, acrylic resin, acrylonitrile-
Styrene resin, vinylidene chloride resin, AAS (AS
A) resin, AES resin, fibrin derivative resin, thermoplastic polyurethane, polyvinyl butyral, poly-4-methylpentene-1, polybutene-1, rosin ester resin and the like, among which styrene-acrylic acid ester copolymer The terpolymer of styrene-acrylic acid ester-acrylic acid is particularly preferable. The thickness of the heat softening layer is
Usually, it is set in the range of 3 to 15 μm.

A single layer or a plurality of layers of conductive particles are formed in the vicinity of the surface of the heat-softened layer, that is, within a few times the diameter of the conductive particles from the surface. The size of the conductive particles is 0.05
It is preferably in the range of ˜1 μm. If the size of the conductive particles is too large, it becomes difficult for the conductive particles to move, and
If it is too small, it becomes difficult to be charged, which is not preferable. Also,
When the conductive particles have a thin film shape, they are difficult to move, which is not preferable.

As the conductive material forming the conductive particles, carbon oxide, copper iodide, silver iodide, zinc sulfide, silicon carbide and the like, as well as metal oxides are preferably used. In particular, metal oxides containing oxygen vacancies and those containing a small amount of a foreign atom forming a donor with respect to the metal oxide used are preferable because they have high conductivity, that is, they contain many electron-hole pairs. . Examples of metal oxides include
ZnO, SnO ₂ , TiO ₂ , In ₂ O ₃ , MoO
₃ or the like, or a composite oxide of these, and examples of containing a different atom include ZnO, Al, In, etc.
Examples thereof include those containing Nb and Ta for TiO ₂ and those containing different atoms such as Sb, Nb, In and halogen elements for SnO ₂ . The addition amount of these heteroatoms is 0.0
The range of 1 to 30 mol% is preferable, and the range of 1 to 10 mol% is particularly preferable.

As a method for forming the conductive particle layer by embedding these conductive particles in the vicinity of the surface of the thermal softening layer, vapor deposition method (resistance heating, electron beam heating), ion plating method, glow discharge sputtering method, An ion beam sputtering method or the like can be used. For example, in the case of the vapor deposition method, the thermosoftening layer may be heated to be in a softened state and the conductive material may be evaporated under a low pressure of 10 to 10 ⁻³ Torr. As a result, the conductive material is aggregated on the surface of the heat-softening layer to form a fine particle having a particle size of 1 to 0.1 μm, and the particles are aligned in a single layer or in a plurality of layers to form a surface of the heat-softening layer. Embedded in the vicinity of. The glow discharge sputtering method known as a method for forming a transparent conductive film on a plastic film such as polyester can be used as it is for producing the image holding member of the present invention. Also in this case, by heating the thermosoftening resin in advance, the conductive material becomes fine particles and a conductive particle layer is formed near the surface. As another method of forming the conductive particle layer in the vicinity of the surface of the heat-softening layer, the conductive particles are dispersed in a coating solution having the same composition as the coating solution for forming the heat-softening layer, and the dispersion is used for the heat-softening layer. It is possible to apply a wet method of applying the above. In this case, when the dispersion liquid is applied, it is necessary to quickly dry the coating film of the dispersion liquid so that the thermosoftening layer existing in the lower layer is not dissolved.

The image holding member used in the present invention has conductive fine particles on the heat-softening layer, but since the conductive fine particle layer is very thin, the light transmittance is 95% or more. Therefore, the exposure is rarely weakened.
On the other hand, the heat softening layer can be operated almost in the same manner as the charge transporting layer in a usual electrophotographic photoreceptor. However, since the thermosoftening resin is used, it is inferior in durability, but can sufficiently endure the application of the electrophotographic method by the Carlson method.

Next, the electrophotographic method of the present invention will be described. FIG. 2 is a schematic configuration diagram of an example of an electrophotographic apparatus for carrying out the electrophotographic method of the present invention. In FIG. 2, the image holding member 10 is mounted on a pipe 11 to form a photoconductor drum, around which a corona charger 60, a diode 12 for emitting a light (laser beam) 61, a developing device 71,
A transfer charger 13, a cleaner 14 and a charge eliminator 15 are provided. Incidentally, 9 is a transfer paper. FIG. 3 is a schematic configuration diagram of another example of an electrophotographic apparatus for carrying out the electrophotographic method of the present invention. In FIG. 3, a lens system is used as the exposure device. That is, the image of the original 16 is irradiated by the light from the light source 17 through the lens 18 to the image holding member 10. In this apparatus, a developing device 71 that stores a positively chargeable developer,
A developing device 81 that stores a negatively chargeable developer is provided. Other symbols mean the same as above.

A case where an image is formed on the image holding member by the Carlson method will be described with reference to the drawings. 4 (a) to 4 (c) are drawings for explaining a method of producing a copy by the Carlson method. First, FIG.
As shown in (a), the corona charger 60 is relatively moved with respect to the image holding member 10 to negatively charge the surface. As a result, the above-mentioned conductive particles have electron-hole pairs at room temperature, and holes are immediately released to the negative charges on the surface to neutralize the surface charges through the charge transport material. Then, negative charges remain inside the conductive particles. At that time, when the surface potential is measured, it is about 80 to 95% as compared with the case where the conductive particles are not present.

Next, as shown in FIG. 4B, image exposure is performed. Reference numeral 61 is light that sensitizes the charge generation layer, and most of the light reaches the charge generation layer 3 through the sufficiently thin conductive particle layer. In the case of a diode laser beam, it is image-wise modulated by an electronic means and exposed, and in that case, the laser beam may be applied to a portion to which the developer is attached. As a result, positive charges are injected from the charge generation layer into the thermal softening layer and are transported through the layer to neutralize the negative charges of the conductive particles. On the other hand, negative charges remain in the conductive particles in the parts that were not exposed to the light.

In the formed latent image, since the potential of the exposed portion is low, the reversal development is performed by using the negative charging developer 8. Thereby, as shown in FIG. 4C, the latent image of the exposed portion is visualized. Then, a copy can be obtained by transferring to the transfer paper 9 by a conventional method. The developer remaining after the transfer onto the transfer paper is then removed by a cleaner and discharged by a charge eliminator to prepare for the next cycle or image storing process. It should be noted that the above-mentioned Carlson method of making a copy may be repeated.

When the exposure is performed by using the diode laser light, the exposure is performed by modulating so as to obtain a Yin Yang inverted image (that is, an image in which a black portion and a white background portion are inverted) as shown in FIG. 5 (a). You may let me. At that time, in the portion exposed to the light, a positive charge is injected from the charge generation layer into the thermal softening layer and is transported in the layer to neutralize the negative charge of the conductive particles. On the other hand, a negative charge remains in the conductive particles in the part that was not exposed to the light. (See FIG. 5 (a)) Next, when development is performed using the positively chargeable developer 7, a portion not exposed to light is visualized and then transferred to the transfer paper 9. (See FIG. 5 (b))

Next, the continuous copying method will be described. The continuous copying method includes an image storing step of storing image information in the image holding member and a continuous copying step of copying using the image holding member in which the image information is stored. First, the image storing step of storing the image information will be described. In the image storing step, as shown in FIG. 6, first, in the same manner as shown in FIG. The charger 60 is moved relatively to give a negative charge to the surface. (See FIG. 6A) Next, image exposure is performed in the same manner as shown in FIG. As a result, in the portion exposed to the light, positive charges are injected from the charge generation layer into the thermal softening layer and are transported through the layer to neutralize the negative charges of the conductive particles. On the other hand, in the portion not exposed to the light, negative charges remain on the conductive particles. (See FIG. 6 (b))

Thereafter, as shown in FIG. 6C, the image holding member is heated by heat 62. As a heating method,
Any method such as a method of passing it through a heating roller, a method of putting it in a heating container, or a method of heating with a heating wire can be adopted, and heating is performed for several seconds at a temperature not lower than the Tg of the thermosoftening resin. As a result, the conductive particles having the negative charges remaining therein move to the side of the base body to be an electrode in the heat-softened layer which is softened and whose viscosity is lowered, by electrostatic attraction. On the other hand, the heating lowers the electrical resistance of the thermosoftening layer, and the electric charge of the conductive particles suddenly discharges spontaneously.Therefore, the conductive particles do not all move to the electrode side, and the particle size and charge Due to variations in density, etc.
It stops sparsely in the heat-softened layer. In this way, a portion containing the moved conductive particles (moving particles 52) is formed. Then, if the image holding member is returned to room temperature,
The image holding member 20 in which the image information is stored is obtained.

Next, the continuous copying process for obtaining a copy by using the image holding member in which the image information is stored as described above will be described. As shown in FIG. 7A, the charging device 60 negatively charges the entire surface of the image holding member in which the image information is stored. As a result, in the portion where the conductive particles (non-moving particles 51) that have not moved exist,
Similar to the case shown in (a), negative charges remain on the conductive particles, and the surface potential is 85 to 85 when the conductive particles do not exist.
It will be about 95%. On the other hand, in the portion where the moved conductive particles (moving particles 52) are present, positive charges are successively injected from the particles closer to the electrode to neutralize the negative charges on the surface side, and as a result, The surface potential is 0 to 20%, which is very low compared to the case where no conductive particles are present. Therefore, a latent image having an electrostatic contrast corresponding to the image is formed only by uniform negative charging on the entire surface. The latent image thus formed is developed using the positively chargeable developer 7. Thereby, the latent image is visualized, and then transferred to the transfer paper 9 by a conventional method to obtain a copy. (See FIG. 7 (b))

After that, by recharging, as shown in FIG.
A latent image can be formed as shown in (a), and therefore copying can be continuously performed without performing image exposure. After copying, cleaning can be performed as needed. The image holding member after the completion of copying is discarded and replaced with a new one.

[0025]

【Example】

Example 1 A 50 μm-thick polyester film having a conductive layer on which aluminum was vapor-deposited was used as a substrate. 5 parts by weight of copolymer nylon (trade name: CM8000, manufactured by Toray Industries, Inc.) was dissolved in 40 parts by weight of methanol and 60 parts by weight of butanol. Anatase type titanium oxide (trade name: Taipaque W-10, manufactured by Ishihara Sangyo Co., Ltd.) was added to the obtained solution.
15 parts by weight was added and dispersed by a ball mill. The obtained dispersion is applied with a wire bar and the temperature is 100 ° C. for 10 minutes.
After drying for a minute, an undercoat layer having a film thickness of 2 μm was formed. This layer had a function of preventing interference of laser light. Next, 8 parts by weight of a solution prepared by previously dissolving 1 part by weight of polyvinyl butyral resin (ESREC BM-1, manufactured by Sekisui Chemical Co., Ltd.) in 19 parts by weight of cyclohexanone, 1.6 parts by weight of X-type phthalocyanine and 1 part of cyclohexanone
The mixture was mixed with 2.8 parts by weight, and the dispersion treatment was performed for about 1 hour by a paint shaker using glass beads having a diameter of about 2 mm as a dispersion medium. The obtained dispersion was applied onto the undercoat layer with a wire bar and dried at 100 ° C. for 10 minutes to form a charge generation layer having a film thickness of 0.3 μm.

On the other hand, 62 parts by weight of styrene, 36 parts by weight of ethyl acrylate, and 2 parts by weight of acrylic acid were used as starting materials.
Weight average molecular weight of about 80 synthesized using toluene as solvent
00 terpolymer was prepared. The Tg of this polymer is 48
C. and the viscosity at 110.degree. C. was 28,000 poise. 78 parts by weight of this polymer and N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1 '
22 parts by weight of -biphenyl] -4,4 'diamine were dissolved in 500 parts by weight of toluene. The obtained solution was applied onto the charge generation layer with a wire bar and dried at 110 ° C. for 15 minutes to form a heat softening layer having a film thickness of 8 μm. Next, 1 part by weight of tin oxide-indium oxide (ITO) powder,
6 parts by weight of the terpolymer, 2 parts by weight of the charge transport material,
A mixture consisting of 50 parts by weight of toluene and 50 parts by weight of butanol was treated with a ball mill to obtain a dispersion liquid. The average particle size of the dispersed particles was 0.35 μm. This dispersion was applied onto the heat-softened layer with a wire bar so that the film thickness after drying would be 0.6 μm. When the spectral sensitivity of the formed image holding member was measured, the results shown in FIG. 8 were obtained.

Next, using this image holding member, copying was first performed in the copy mode by the Carlson method. Using the electrophotographic copying machine shown in FIG. 2, the image holding member is 84 mm.
It was wound around a φ × 320 mm aluminum pipe to obtain a photosensitive drum. The surface was negatively charged under the condition of -600V. As a result, the negative charge was transferred to the ITO particles and the surface potential became −570V. Next, by a diode laser beam, the black portion (character portion) of the original document was extinguished and the white background portion of the original document was illuminated so as to be image-wise modulated, and exposure was performed at an intensity of 12 ergs / cm ² . The potential of the exposed portion was -100V. Next, development was performed using a positively chargeable developer, and the image was transferred to the paper 9, whereby a copy image could be obtained. The copy speed at this time is
The A4 size paper was 4 sheets per minute.

Continuous copying was performed in the print mode based on the image storage system. That is, after the image holding member is charged under the condition of −600 V, the diode laser beam modulates the black portion (character portion) of the document to emit light and the white background of the document is extinguished to perform image exposure. It was After that, heat treatment was performed by passing the heat roll on a heat roll kept at 115 ° C. in a dark place for 5 seconds. As a result, the unexposed areas of the ITO
The particles moved to the substrate side. As described above, the storage by writing the image is completed.

The image holding member in which the obtained image information was stored was wound around the same aluminum pipe as above, and a print test was conducted. That is, -6 with a corona charger
It was charged to 00V. As a result, the exposed portion (the portion where the conductive particles did not move) became −570V and the non-exposed portion (the portion where the conductive particles moved) became −80V. In that state, development was performed with a positively chargeable developer in the same manner as described above, and then transferred to a sheet to obtain a printed image. In this print mode, it was not necessary to perform image exposure, and no problems occurred even after continuous printing of 2000 sheets. The printing speed at that time was 100 sheets per minute because no image writing was required.

Example 2 In this example, the image holding member produced in Example 1 was used to form an image by electrophotography using an optical lens exposure instead of a laser beam. Using the electrophotographic apparatus shown in FIG. 3, an image holding member was wound around an 84 mmφ × 320 mm aluminum pipe to form a photosensitive drum. First, a copy image was prepared by the Carlson method. That is, after the surface of the image holding member was charged to −600 V, image exposure was performed. As a result, the potential of the black part (character part) is -560V and the potential of the white part is -100V
Became. After that, development was performed by a developing device having a positively chargeable developer, and the image was further transferred onto a sheet. By repeating this operation, 1000 copies could be obtained. However, the copy speed was 20 sheets per minute in A4 size. Next, copying was performed in the print mode by the continuous copying method. That is, after the electrostatic latent image is formed on the image holding member by the same operation as in the Carlson method, the image holding member is heated to 115 ° C.
It was heated for 5 seconds. As a result, the ITO particles in the black part moved to the substrate side, and the storage of the image was completed. Using this image holding member, a print test was conducted by the electrophotographic apparatus shown in FIG. That is, it is charged to −600 V by using a charger so that the black portion is −80 V and the white background portion is −57 V.
It became 0V. Next, development was performed using a developing device having a negatively chargeable developer, and the developer was attached to the black portion. Then, the transfer was performed on the paper. In that case, the polarity of the transfer charger is
It was negative in copy mode, but changed to positive in print mode. With the above operation, continuous printing of 2000 sheets was performed at a speed of 100 sheets per minute, but no problem occurred.

[0031]

Since the present invention has the above-mentioned structure, continuous copying can be performed in the print mode based on the continuous copying method in addition to the normal Carlson based copying mode. Therefore, when a large number of copies are required, it is possible to perform so-called off-printing for density, alignment, etc. before continuous copying, and it is possible to adjust the exposure state and the like. . Further, if a Carlson method is adopted when a small number of sheets are copied, there is an advantage that the image holding member does not have to be discarded, and wasteful operation and a large reduction in cost can be achieved.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an image holding member used in the present invention.

FIG. 2 is a schematic configuration diagram of an electrophotographic apparatus of a method of exposing with a diode laser beam for carrying out the present invention.

FIG. 3 is a schematic configuration diagram of an electrophotographic apparatus of the type that exposes with an optical lens for carrying out the present invention.

FIG. 4 is a diagram illustrating an example of a copying process by the Carlson method according to the present invention.

FIG. 5 is a diagram illustrating another example of a copying process by the Carlson method according to the present invention.

FIG. 6 is a diagram illustrating an image storing process according to the present invention.

FIG. 7 is a diagram illustrating a continuous copying process in the present invention.

8 is a graph showing the spectral sensitivity characteristics of the image holding member in Example 1. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Conductive layer, 3 ... Charge generating layer, 4 ... Thermal softening layer, 5 ... Conductive particles, 7 ... Positively chargeable developer, 8 ... Negatively chargeable developer, 10 ... Image holding member, 11 … Pipe, 12… Diode, 13… Transfer charger, 14… Cleaner, 15
... static eliminator, 16 ... manuscript, 17 ... light source, 18 ... lens, 2
0 ... Image holding member storing image information, 51 ... Non-moving particles, 52 ... Moving particles, 60 ... Corona charger, 61 ... Light,
62 ... Heat, 71 ... Developing device, 81 ... Developing device.

Claims (4)

[Claims] 1. A conductive surface of a substrate, on which at least a charge generation layer and a thermal softening layer composed of a charge transport substance and a thermal softening resin are sequentially laminated, and conductive particles are embedded in the vicinity of the surface of the thermal softening layer. The image holding member provided with a conductive particle layer formed by forming a copy image by the Carlson method including at least charging, image exposure, toner development, transfer to paper, and cleaning, or Subsequently, the image holding member is negatively charged to accumulate electric charges in the conductive particles, and then image exposure corresponding to the image information is performed to eliminate the electric charges of the conductive particles in the exposed portion, and then heat softening. An image storage step of heating the layer to a temperature equal to or higher than the softening point of the thermosoftening resin to move the conductive fine particles in which the charge is accumulated in the thermosoftening layer to store the image information, and storing the image information. It An electrophotographic method characterized in that a copied image is formed on the formed image holding member by a continuous copying method having a continuous copying process including charging, toner development, transfer to a sheet, and cleaning. 2. The electrophotographic method according to claim 1, wherein image exposure is performed using a laser beam modulated by an electric signal. 3. The electrophotographic method according to claim 2, wherein the image exposure by the Carlson method and the image exposure in the image storing step are positive image reversal image exposure. 4. A toner development in the Carlson system,
2. The electrophotographic method according to claim 1, wherein one of toner development in a continuous copying method in which continuous copying is performed using an image holding member in which image information is stored is reversal development for developing a portion having a low potential.