JPH11119518A - Formation of image using ferroelectric substance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable long-term stable preservation of latent images in a bright room, the occasional writing and erasing of images and the formation of plural sheets of toner images with one time of writing of the latent images. SOLUTION: This image forming method consists of a first stage for arraying the dipoles of a ferroelectric substance of a ferroelectric element having a ferroelectric layer contg. an oxide ferroelectric substance of an inorg. system expressed general formula (1) or (2) mentioned below in one direction, a second stage for inverting the dipoles of an image part or non-image part, a third stage for uniformly heating the ferroelectric layer, then cooling this layer to develop the electrostatic latent image and a fourth stage for developing this electrostatic latent image. The oxide ferroelectric substance of the inorg. system expressed by the formula [(Bi2 O2 )<2+> (XY2 O7 )<2-> ], [X; Sr, Pb, Na0.5 Bi0.5 , Y; Ta, Nb] or the formula [Xn Bi4 Tin+3 O3n+12 ] [X; Sr, Ba, Pb, Na0.5 Bi0.5 , n; 1, 2].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method, and more particularly, to an image forming method of forming an electrostatic latent image using a ferroelectric substance and then visualizing the electrostatic latent image using toner. About the method.

[0002]

2. Description of the Related Art In general, an electrophotographic method, which is one of image forming methods used in copying machines and printers, charges a photosensitive member having a photosensitive layer composed of a photoconductor and then exposes the photosensitive member by image exposure. Form an electrostatic latent image on the photosensitive layer of the body, develop it with electrostatic toner, transfer the toner image on the photoconductor to film, plain paper, etc., and fix the transferred toner image To form a visible image. To form the same visible image again, the toner adhered to the photoconductor is cleaned, charged again, and the same steps such as image exposure, transfer, and fixing are repeated. Therefore, when a plurality of identical images are created, the copying speed is limited, and high-speed copying is difficult.

In order to solve this problem, "Photographic Science and Engineering (Ph.
otographic Science and Engineering ”Vol. 25 (1981)
Years) pp. 35-39 and 209-215 propose an electrophotographic photosensitive member having memory properties. According to this method, once image exposure is performed, a plurality of copies can be made by repeating the above-described steps from development to fixing.

However, the electrophotographic photoreceptor described in this document cannot store a latent image formed by image exposure for a long period of time, has a problem in memory, and cannot store it in a bright room. In addition, printing durability and environmental stability are poor, and they have not been put to practical use.

Also, a ferromagnetic material is used to form a latent image having memory properties according to the magnitude of its magnetic susceptibility, developed using a magnetic toner, transferred, fixed and transferred to a plurality of visible images by one image writing. Such as "Repro MG8000" (manufactured by Iwasaki Tsushinki), "Varipress M450" (Bull-Nipson)
Has been put to practical use.

Further, Japanese Patent Application Laid-Open No. Hei 5-221139 discloses that after an organic ferroelectric layer is subjected to a poling (dipole orientation) treatment, light is applied to write an image so that the exposed portion has a Curie point (Tc) or more. To form a latent image,
A recording method capable of continuous copying and storing a latent image has been proposed.

[0007]

As described above, the conventional electrophotographic method using a photoconductor is used in various fields such as a printer, a copying machine, and a direct plate making. Must be performed in a dark room,
Also, in order to create a plurality of identical images, the toner attached to the photoconductor is cleaned and then charged again, and then the same processes such as image exposure, transfer, and fixing are repeated. High-speed copying is difficult.

Further, in the method using a ferromagnetic material, a magnetic head is used as a writing head, so that the resolution is limited, and it is difficult to produce a color magnetic toner, so that a color image cannot be produced. There is a point.

Further, in writing an image using an organic ferroelectric substance, a method of irradiating light and heating an exposed portion to a temperature equal to or higher than the Curie point (Tc) to form a latent image is a method of forming a latent image. Due to the low mechanical strength, the surface is easily scratched by toner development or the like, and such scratches make it easier for toner to adhere to the non-image area, and the stain on the non-image area increases as the number of printed sheets increases. There is a problem. For this reason, there are problems that the method of toner development is limited and that the method is not suitable for printing many sheets.

Problems to be solved by the present invention are charging,
Image exposure and development can be performed in a bright room,
Colorization of images is possible, charging, image exposure, writing and erasing of images at any time are possible, it is possible to create multiple sheets of the same toner image with one image writing, and further mechanically An object of the present invention is to provide an image forming method using a ferroelectric material, which has high strength, is hardly scratched on the surface by toner development or the like, does not limit the method of toner development, and is suitable for printing many sheets.

[0011]

Means for Solving the Problems As a result of intensive studies, the present inventors have formed a latent image using a specific inorganic oxide ferroelectric and formed a toner image by electrophotography. Thus, the present invention has been completed.

That is, in order to solve the above problems, the present invention provides (1) a ferroelectric element in a ferroelectric element in a ferroelectric element having a ferroelectric layer containing a ferroelectric substance on a conductive support. A first step of arranging the dipoles of the body in one direction, (2) a second step of inverting the dipole in a portion corresponding to an image portion or a non-image portion, and (3) uniform heating of the ferroelectric layer. rear,
In the image forming method comprising: a third step of cooling to develop an electrostatic latent image and (4) a fourth step of developing the electrostatic latent image with toner, the ferroelectric used for the ferroelectric layer is General formula (1)

[0013]

Embedded image [(Bi ₂ O ₂ ) ²⁺ (XY ₂ O ₇ ) ^2- ]

Wherein X is Sr, Pb or Na _0.5 B
i represents _0.5 , and Y represents Ta or Nb. ] Or an inorganic oxide ferroelectric represented by the general formula (2):

[0015]

Embedded image _{[X n Bi 4 Ti n +} 3 O 3n + 12]

Wherein X is Sr, Ba, Pb or Na
_0.5 represents Bi _0.5 , and n represents 1 or 2. And an image forming method using an inorganic oxide ferroelectric material represented by the formula:

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A ferroelectric element used in an image forming method of the present invention comprises a ferroelectric layer and a conductive support layer. As shown in FIG. 1 or FIG. The conductive support layer may be in close contact with the conductive support layer, or an intermediate layer may be provided between the ferroelectric layer and the support layer.

The inorganic oxide ferroelectric represented by the general formula (1) used for the ferroelectric layer and the general formula (2)
Inorganic oxide ferroelectrics represented by the formula, the orientation of the dipole and the reversal of the dipole of the image part or non-image part by corona charging etc. should be possible, and the spontaneous polarization of the ferroelectric The electric resistance decreases when the temperature rises from normal temperature, and the electric resistance decreases when the temperature rises from normal temperature. Further, these inorganic oxide ferroelectrics preferably have a layered structure. These inorganic oxide ferroelectrics can be used alone or in combination of two or more.

The conductive support layer is not particularly limited as long as it has the necessary mechanical strength and smoothness and has conductivity, and the material is not particularly limited. Metals such as platinum and aluminum,
Conductive inorganic materials such as conductive polymers and carbon black,
And the like, and a laminate obtained by laminating a conductive film on plastic, paper, or another insulating substrate may be used.

The ferroelectric element used in the image forming method of the present invention includes, for example, (A) a method of forming a ferroelectric layer on a conductive support layer, and (B) a ferroelectric layer and a conductive support. A method in which the body layers are separately manufactured and then bonded to each other.

In the method (A), a ferroelectric material, a resin, and a solvent are mixed and dissolved, and the mixed solution is subjected to a dipping method, a bar coating method, a roll coating method, a spray coating method, a spin coating method, or the like. A method of forming a ferroelectric layer by removing a solvent after coating on a substrate, a method of further sintering the ferroelectric layer obtained above to form a ferroelectric layer, and a method of mixing A method in which a solution is used to form a film by an electrodeposition method to form a ferroelectric layer, and on a support layer, an organometallic complex decomposition method (MOCVD method), which is one of a magnetron sputtering method, a laser ablation method, and a chemical vapor deposition method ) Or a method of laminating ferroelectrics by a sol-gel method or the like.

As the method (B), there is a method in which a ferroelectric film is formed by a solid-phase reaction or the like, and the ferroelectric film is brought into close contact with a support layer using a conductive adhesive.

When a resin is used for forming the ferroelectric layer, examples of the resin material include polyvinyl butyral, polyester, polycarbonate, epoxy resin, and polymethyl methacrylate.

The solvent used for the mixed solution for forming the ferroelectric layer is a solvent which does not deteriorate the inorganic oxide ferroelectric substance and may be any solvent which can dissolve or disperse the resin material. Examples of suitable solvents include ketone solvents such as acetone and methyl ethyl ketone; chlorine solvents such as dichloromethane and 1,2-dichloroethane; and aromatic polar solvents such as toluene.

The thickness of the ferroelectric layer is such that a dipole is oriented by applying an electric field. If the thickness is too large, a high charging voltage is required or charging tends to be required repeatedly. On the contrary, if the thickness is too small, the difference between the surface potential of the image area and the surface potential of the non-image area tends to be small, and it tends to be difficult to form a visible image with toner.
The range of μm is preferred.

In the first step of the image forming method of the present invention, the method of arranging the ferroelectric dipoles in the ferroelectric layer in one direction (hereinafter referred to as dipole alignment treatment) is based on corona charging. A charging method used in electrophotography such as a method and a method using a roller electrode can be used.

The dipole alignment treatment by corona charging can be performed using a corona charger of a usual corotron type or scorotron type. In addition, the dipole orientation treatment by roller charging is performed by bringing a conductive rubber roller to which a high voltage is applied into contact with a dielectric layer, for example, with a resistance value of 10 ⁵ to 1.
0 ⁹ [Omega] cm approximately conductive method of charging by applying a few hundred volts or more voltage to the rubber roller, the resistance value 10 ³ to 10 ⁵ Omega
There is a method of attaching a fibrous wire rod having a thickness of cm to the surface of the conductive roller in a brush shape to enhance the contact property, and applying a high voltage to the conductive roller to charge the conductive roller. In both cases, a suitable method may be selected according to the system configuration of the apparatus.

The time required for dipole alignment is corona voltage,
It depends on the applied voltage of the roller electrode or its shape, and can be appropriately set according to the system configuration of the apparatus, the method of use of the apparatus, or the application.

In the second step of the image forming method of the present invention, the method of inverting the dipole in the portion corresponding to the image portion or the non-image portion includes a method in which a portion corresponding to the image portion or the non-image portion is corona-charged through a mask. And a method of inverting a dipole corresponding to an image portion or a non-image portion using a stylus head, a method of inverting a dipole of an image portion or a non-image portion by ion flow, and the like. No.

When the volume resistivity of the ferroelectric substance is small, for example, 10 ¹⁰ Ωcm, the electric field of the corona is not sufficiently applied, and the orientation of the dipole and the reversal of the dipole in the image portion or the non-image portion are suppressed. However, since the writing is not performed sufficiently, the image writing tends to be unsatisfactory.

Further, when the relative dielectric constant of the ferroelectric substance is large, for example, when it is 1000 or more, the electrostatic capacity is large. Therefore, when the film thickness is about 100 μm, an electrostatic contrast sufficient for toner development can be obtained. Because they tend not to be
The relative permittivity of the ferroelectric material is preferably small.

The capacitance of the ferroelectric layer can be reduced by increasing the film thickness. This increases the corona electric field required for dipole orientation and the like and the energy required for heating and cooling. It tends to increase significantly,
It is not preferable to increase the film thickness.

In order to convert the written latent image into an electrostatic latent image, in the third step of the image forming method of the present invention, a ferroelectric element in which a dipole of a portion corresponding to an image portion or a non-image portion is inverted. Body layer below the ferroelectric / paraelectric phase transition point of the dielectric,
After heating, it is cooled to develop an electrostatic latent image. It is essential that ferroelectrics have ferroelectricity at room temperature, and since the orientation of the dipoles of the ferroelectrics is resolved beyond the ferroelectric-paraelectric phase transition point, the stability of image information is reduced. Therefore, it is necessary to keep the heating temperature lower than the ferroelectric-paraelectric phase transition point.

By heating the ferroelectric layer to a temperature below the ferroelectric-paraelectric phase transition point, the spontaneous polarization of the ferroelectric is reduced, the bound surface charges become free charges, and in the heated state, , Since the electric resistance of the ferroelectric layer becomes lower,
This free charge leaks.

By cooling from the heated state, the spontaneous polarization reversibly returns to its original size, but the leaked surface charge is irreversible, so that a potential is generated due to the spontaneous polarization. Therefore, it is necessary that the spontaneous polarization of the ferroelectric decreases at a temperature rise from room temperature, and that the electric resistance of the ferroelectric layer decreases at a temperature rise from room temperature.

A device that heats the ferroelectric layer immediately after heating is suitable, and a device in which a heating element such as a heat roll contacts the ferroelectric to heat it is used. The smaller the heat capacity, the better.

As a means for heating the ferroelectric, a method of irradiating light or the like and converting the energy into heat can be used. The method of irradiating light is particularly preferable in that the method is non-contact and the temperature is lowered immediately after heating.

Examples of the light source of the light irradiation device include an infrared lamp, a halogen lamp, a xenon lamp, a metal halide lamp, an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a laser and the like.

In the method of heating by irradiating light, the light irradiation time and irradiation intensity require a certain intensity or more, but the emission wavelength of the light source, the absorption wavelength of the light absorbing material,
Since the optimum value of the light intensity to be irradiated varies depending on conditions such as the heat capacity of the ferroelectric element, it is necessary to select appropriate conditions as appropriate. That is, an appropriate value may be selected for the intensity of the irradiated light depending on conditions such as the emission wavelength, the absorption wavelength of the light absorbing substance, and the heat capacity of the ferroelectric element.

It is effective to uniformly irradiate the ferroelectric layer temporally and planarly in order to uniformly heat the inside of the ferroelectric layer.

In the fourth step of the image forming method of the present invention,
After forming an electrostatic latent image, at a temperature showing ferroelectricity,
The latent image is developed into a visible image by developing using an electrostatic powder toner or a liquid toner.

As the electrostatic powder toner and the liquid toner, appropriate ones may be selected from commercial products.

The toner image developed on the surface of the ferroelectric layer is electrostatically transferred to the plain paper or film by superimposing plain paper or a film and then charging the back of the plain paper or film. After that, fixing may be performed.

In order to continuously produce a plurality of identical images, if the surface of the ferroelectric layer has a surface potential contrast that allows electrostatic toner development, the electrostatic toner development, transfer, and fixing are successively performed. Just do it.

When the surface potential contrast or the like is lowered due to the influence of the transfer conditions or the surrounding environment, the surface potential contrast is formed by heating and cooling the ferroelectric layer, if necessary, and then the toner development is performed. Then, transfer and fixing may be performed.

[0046]

The present invention will be described in more detail with reference to the following examples. However, the invention is not limited to these examples. In the following examples, “%” represents “% by weight”.

Example 1 Strontium carbonate (SrC)
After sufficiently mixing 1 g of O ₃ ), 1.35 g of titanium oxide (TiO ₂ ) and 3.16 g of bismuth trioxide (Bi ₂ O ₃ ), the mixture was sintered at 810 ° C. for 1 hour using an electric furnace. The mixture after sintering was pulverized using a mortar to obtain powdery Sr ₂ Bi ₄ Ti ₅ O ₁₈ .

The thus obtained Sr ₂ Bi ₄ Ti ₅ O ₁₈
Powder 2.5%, polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) 2.5% and methyl ethyl ketone 4
The mixture consisting of 7.5% was dispersed and mixed by ball milling for 1 hour.

The dispersion mixture thus obtained was applied on a nickel substrate using a bar coater so that the film thickness after drying was 100 μm, and then dried by heating at 60 ° C. for 3 hours. By sintering at 1000 ° C. to form a ferroelectric layer, a ferroelectric element was obtained.

The pulse width of the ferroelectric element is 0.1
The alignment treatment was performed by applying a negative corona pulse having a voltage of 6 kV 50 times per second.

Through an arbitrary mask, a pulse width of 0.2
By applying a positive corona pulse having a voltage of 6 kV for 100 times per second, the polarization was inverted only in the portion corresponding to the image portion.

Next, the ferroelectric element was heated to 150 ° C. using a heater, and then cooled to form an electrostatic latent image. When the electrostatic latent image was visualized on the ferroelectric element treated in this manner using a powder toner of positive polarity, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to plain paper is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

After storing this ferroelectric element in a bright room for one month, the ferroelectric element was heated to 150 ° C. using a heater and then cooled to form an electrostatic latent image. When the electrostatic latent image was visualized on the thus treated ferroelectric element using the powder toner of the positive electrode, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated and cooled, and development, transfer and fixing are repeated in the same manner as in the first sheet to obtain a plurality of arbitrary images. I got

Further, the ferroelectric element was subjected to an alignment treatment by applying a negative corona pulse having a pulse width of 0.1 second and a voltage of 6 kV 50 times. By applying a positive corona pulse having a pulse width of 0.2 seconds and a voltage of 6 kV 100 times through an arbitrary mask, the polarization was inverted only in the portion corresponding to the image area. Next, the ferroelectric element was heated to 150 ° C. using a heater, and then cooled,
An electrostatic latent image was formed. When the electrostatic latent image was visualized on the ferroelectric element treated in this manner using a powder toner of positive polarity, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to plain paper is heated and then cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

Example 2 Strontium carbonate (SrC)
After sufficiently mixing 1 g of O ₃ ), 1.35 g of titanium oxide (TiO ₂ ) and 3.16 g of bismuth trioxide (Bi ₂ O ₃ ), the mixture was sintered at 810 ° C. for 1 hour using an electric furnace. The mixture after sintering was pulverized using a mortar to obtain powdery Sr ₂ Bi ₄ Ti ₅ O ₁₈ .

The thus obtained Sr ₂ Bi ₄ Ti ₅ O ₁₈
Powder 50%, polycarbonate (“PCZ” manufactured by Mitsubishi Chemical Corporation) 2.5%, 1,2-dichloroethane
A mixture of 5%, 7.5% dichloromethane and 25% toluene was dispersed and mixed for 1 hour by ball milling.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 80 μm, and then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the transfer of the visible image to plain paper is heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image in the same manner as in Example 1. When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, then cooled, and development, transfer, and fixing are repeated in the same manner as in the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of an image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated, then cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

Example 3 Strontium carbonate (SrC)
After sufficiently mixing 1 g of O ₃ ), 2.16 g of titanium oxide (TiO ₂ ) and 6.31 g of bismuth trioxide (Bi ₂ O ₃ ), the mixture was sintered at 820 ° C. for 1 hour using an electric furnace. The sintered mixture was pulverized using a mortar to obtain powdery SrBi ₄ Ti ₄ O ₁₅ .

The thus obtained SrBi ₄ Ti ₄ O ₁₅ powder 5%, polyvinyl butyral (“B” manufactured by Sekisui Chemical Co., Ltd.)
H-3 ") A mixture consisting of 3% and acetone 92% was dispersed and mixed using an ultrasonic homogenizer.

After two stainless steel (SUS-304) substrates were inserted into the dispersion mixture in parallel at an interval of 1 cm, a DC voltage of 300 V was applied between the two substrates for 20 seconds.

A powder was deposited on the negative electrode side and pulled up from the solution to obtain a ferroelectric element having a ferroelectric layer in which a ferroelectric powder was dispersed in a polyvinyl butyral film.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the transfer of the visible image to plain paper is heated and cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric device in a light room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer and fixing in the same manner as in the first sheet, thereby forming a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, the ferroelectric element was subjected to orientation treatment, polarization reversal of the image portion, heating and cooling to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to the plain paper is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

Example 4 Strontium carbonate (SrC)
O ₃₎ 1 g, bismuth trioxide (Bi ₂ O ₃₎ 3.16g and penta niobium oxide (Nb ₂ O ₅₎ was thoroughly mixed 1.8 g, 1 hour at 880 ° C. using an electric furnace and the mixture Sintered. The mixture after sintering was pulverized using a mortar to obtain powdery SrBi ₂ Nb ₂ O ₉ .

The powder of SrBi ₂ Nb ₂ O ₉ thus obtained, 50%, polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) 2.5%, and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 50 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Embodiment 1, and the first arbitrary image is formed. I got

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated and then cooled.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as in the first sheet, thereby forming a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to plain paper is heated and cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

Example 5 Strontium carbonate (SrC)
O ₃₎ 1 g, bismuth trioxide (Bi ₂ O ₃₎ 3.16g and penta tantalum oxide (Ta ₂ O ₅₎ was thoroughly mixed 2.99 g, 1 hour at 880 ° C. using an electric furnace and the mixture Sintered. The mixture after sintering is crushed using a mortar,
Powder SrBi ₂ Ta ₂ O ₉ was obtained.

The powder of SrBi ₂ Ta ₂ O ₉ thus obtained, 50%, polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) 2.5%, and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate by using a bar coater so that the film thickness after drying was 52 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Embodiment 1, and the first arbitrary image is formed. I got

Further, after transferring the visible image to plain paper, the ferroelectric element is heated and cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to plain paper is heated and cooled, and development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

Example 6 Barium carbonate (BaCO ₃ )
After sufficiently mixing 1 g, 4.72 g of bismuth trioxide (Bi ₂ O ₃ ) and 1.62 g of titanium oxide (TiO ₂ ),
This mixture was sintered at 820 ° C. for 1 hour using an electric furnace. The mixture after sintering was pulverized using a mortar to obtain powdery BaBi ₄ Ti ₄ O ₁₅ .

50% of the powder of BaBi ₄ Ti ₄ O ₁₅ thus obtained, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 62 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the transfer of the visible image to plain paper was heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image in the same manner as in Example 1. When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on the ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated, then cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

Example 7 Barium carbonate (BaCO ₃ )
1 g, bismuth trioxide (Bi ₂ O ₃ ) 2.36 g and titanium oxide (TiO ₂ ) 1.01 g
This mixture was sintered in an electric furnace at 820 ° C. for 2 hours. The mixture after sintering was pulverized using a mortar to obtain powdery Ba ₂ Bi ₄ Ti ₅ O ₁₈ .

The thus obtained Ba ₂ Bi ₄ Ti ₅ O ₁₈
Powder 2.5%, polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) 2.5% and methyl ethyl ketone 4
The mixture consisting of 7.5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 70 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the transfer of the visible image to plain paper was heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image in the same manner as in Example 1. When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric device to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image is transferred to plain paper is heated and cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

Example 8 1 g of lead carbonate (PbCO ₃ )
After sufficiently mixing 1.74 g of bismuth trioxide (Bi ₂ O ₃ ) and 0.99 g of niobium pentoxide (Nb ₂ O ₅ ), the mixture was sintered at 880 ° C. for 2 hours using an electric furnace. The mixture after sintering is pulverized using a mortar to obtain powdered PbBi.
₂ Nb ₂ O ₉ was obtained.

50% of the powder of PbBi ₂ Nb ₂ O ₉ thus obtained, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and 47% of methyl ethyl ketone.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 68 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the visible image was transferred to plain paper was heated and then cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a bright room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated and then cooled, and development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary images are printed. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to the plain paper is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

Example 9 1 g of lead carbonate (PbCO ₃ )
After sufficiently mixing 1.74 g of bismuth trioxide (Bi ₂ O ₃ ) and 1.65 g of tantalum pentoxide (Ta ₂ O ₅ ), the mixture was sintered at 880 ° C. for 2 hours using an electric furnace. The mixture after sintering is pulverized using a mortar to obtain powdered PbB.
i ₂ Ta ₂ O ₉ was obtained.

50% of the powder of PbBi ₂ Ta ₂ O ₉ thus obtained, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 75 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the transfer of the visible image to plain paper was heated and cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image and powdered When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as in the first sheet, thereby forming a plurality of arbitrary images. I got

Further, on this ferroelectric element, an orientation process, polarization reversal of an image portion, heating and cooling were performed in the same manner as in Example 1 to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

(Example 10) Lead carbonate (PbCO ₃ ) 1
g, bismuth trioxide (Bi ₂ O ₃ ) 3.49 g and titanium oxide (TiO ₂ ) 1.2 g were sufficiently mixed, and the mixture was sintered at 820 ° C. for 2 hours using an electric furnace. The mixture after sintering is pulverized using a mortar to obtain powdered PbB.
i ₄ Ti ₄ O ₁₅ was obtained.

50% of the powder of PbBi ₄ Ti ₄ O ₁₅ thus obtained, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 70 μm, and then heated and dried at 60 ° C. for 3 hours to obtain a strong solution. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, after the visible image was transferred to plain paper, the ferroelectric element was heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image in the same manner as in Example 1, and a powder of the positive electrode was formed. When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

(Example 11) Lead carbonate (PbCO ₃ ) 1
g, bismuth trioxide (Bi ₂ O ₃ ) 1.74 g and titanium oxide (TiO ₂ ) 0.75 g were sufficiently mixed, and the mixture was sintered at 820 ° C. for 2 hours using an electric furnace. The sintered mixture is pulverized using a mortar to obtain powdered Pb _2.
Bi ₄ Ti ₅ O ₁₈ was obtained.

The thus obtained Pb ₂ Bi ₄ Ti ₅ O ₁₈
Powder 2.5%, polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) 2.5% and methyl ethyl ketone 4
The mixture consisting of 7.5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 70 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and an arbitrary image on the first sheet is formed. I got

Further, after the visible image was transferred to plain paper, the ferroelectric element was heated and then cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer and fixing in the same manner as in the first sheet, thereby forming a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be formed. Image was obtained.

(Example 12) Sodium carbonate (Na ₂ C)
O ₃ ) 1 g, bismuth trioxide (Bi ₂ O ₃ ) 21.98 g
After sufficiently mixing 10.03 g of niobium pentoxide (Nb ₂ O ₅ ), the mixture was sintered at 880 ° C. for 2 hours using an electric furnace. The mixture after sintering is crushed using a mortar,
Powdery Na _0.5 Bi _2.5 Nb ₂ O ₉ was obtained.

The thus obtained Na _0.5 Bi _2.5 Nb ₂
50% powder of O ₉ , 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 4
The mixture consisting of 7.5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 68 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer and fixing are performed in the same manner as in Embodiment 1, and the first arbitrary image is formed. I got

Further, after the visible image was transferred to plain paper, the ferroelectric element was heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image is transferred to plain paper, the ferroelectric element is heated, then cooled, and development, transfer, and fixing are repeated in the same manner as in the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image has been transferred to plain paper is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

(Example 13) Sodium carbonate (Na ₂ C)
O ₃ ) 1 g, bismuth trioxide (Bi ₂ O ₃ ) 21.98 g
And 16.68 g of tantalum pentoxide (Ta ₂ O ₅ ) were thoroughly mixed, and the mixture was heated at 880 ° C. for 2 hours using an electric furnace.
Sintered for hours. The mixture after sintering was pulverized using a mortar to obtain powdery Na _0.5 Bi _2.5 Ta ₂ O ₉ .

The thus obtained Na _0.5 Bi _2.5 Ta ₂
50% powder of O ₉ , 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 4
The mixture consisting of 7.5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 77 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, the ferroelectric element after the visible image was transferred to plain paper was heated and then cooled, and the same as in the first sheet,
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a light room for one month, it was heated and cooled to 150 ° C. to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer, and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, after the visible image is transferred to plain paper, the ferroelectric element is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, so that a plurality of arbitrary sheets can be obtained. Image was obtained.

(Example 14) Sodium carbonate (Na ₂ C)
O ₃ ) 1 g, bismuth trioxide (Bi ₂ O ₃ ) 39.57
g and 12.06 g of titanium oxide (TiO ₂ ) were sufficiently mixed, and the mixture was sintered at 820 ° C. for 2 hours using an electric furnace. The mixture after sintering was pulverized using a mortar to obtain powdery Na _0.5 Bi _4.5 Ti ₄ O ₁₅ .

The thus obtained Na _0.5 Bi _4.5 Ti ₄
A mixture of 50% of O ₁₅ powder, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and 47.5% of methyl ethyl ketone was subjected to ball milling to give a mixture of 1%.
Time-dispersed and mixed.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 72 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and the first arbitrary image is formed. I got

Further, after the visible image was transferred to plain paper, the ferroelectric element was heated and then cooled.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a bright room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to plain paper, the ferroelectric element is heated and cooled, and the development, transfer and fixing are repeated in the same manner as in the first sheet, whereby a plurality of arbitrary images are transferred. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the transfer of the visible image to plain paper is heated and cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

(Example 15) Sodium carbonate (Na ₂ C)
O ₃ ) 1 g, bismuth trioxide (Bi ₂ O ₃ ) 21.98
g, 7.54 g of titanium oxide (TiO ₂ ) were thoroughly mixed, and the mixture was sintered at 820 ° C. for 2 hours using an electric furnace. The mixture after sintering was pulverized using a mortar to obtain a powdery NaBi ₅ Ti ₅ O _18.

50% of the powder of NaBi ₅ Ti ₅ O ₁₈ thus obtained, 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and methyl ethyl ketone 47.
The mixture consisting of 5% was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied to an alumite-treated aluminum substrate using a bar coater so that the film thickness after drying was 78 μm, and was then dried by heating at 60 ° C. for 3 hours. A ferroelectric element was obtained by forming a dielectric layer.

Using this ferroelectric element, orientation processing, writing of a latent image, formation of an electrostatic latent image, development, transfer, and fixing are performed in the same manner as in Example 1, and an arbitrary first image is formed. I got

Further, after the visible image was transferred to plain paper, the ferroelectric element was heated and then cooled, similarly to the first sheet.
Developing, transferring and fixing were repeated to obtain a plurality of arbitrary images.

After storing this ferroelectric element in a bright room for one month, it was heated and cooled to 150 ° C. in the same manner as in Example 1 to form an electrostatic latent image, When the electrostatic latent image was visualized using the toner, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a similar image.

After the visible image has been transferred to the plain paper, the ferroelectric element is heated, cooled, and repeatedly subjected to development, transfer and fixing in the same manner as the first sheet to obtain a plurality of arbitrary images. I got

Further, in the same manner as in Example 1, an orientation process, polarization reversal of the image portion, heating and cooling were performed on this ferroelectric element to form an electrostatic latent image, and the electrostatic latent image was visualized. Then, the toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the transfer of the visible image to plain paper is heated and cooled, and development, transfer and fixing are repeatedly performed in the same manner as in the first sheet, whereby a plurality of arbitrary sheets can be obtained. Image was obtained.

Comparative Example 1 A solution prepared by mixing and dissolving 15% of a copolymer (weight average molecular weight = about 300,000) composed of 8 parts of vinylidene fluoride and 2 parts of ethylene tetrafluoride and 85% of acetone was prepared as follows. After coating on an aluminum substrate using a spin coater so that the film thickness after drying becomes 5 μm, acetone is evaporated, and heat treatment is further performed at 130 ° C. for 1 hour, and room temperature at a rate of 1 ° C./min. Then, the ferroelectric element was obtained by forming a ferroelectric layer.

The pulse width of this ferroelectric element is 0.1
The alignment treatment was performed by applying a negative corona pulse having a voltage of 6 kV 50 times per second.

Through an arbitrary mask, a pulse width of 0.2
By applying a positive corona pulse having a voltage of 6 kV for 100 times per second, the polarization was inverted only in the portion corresponding to the image portion.

Next, the ferroelectric element was heated to 60 ° C. using a heater, and then cooled to form an electrostatic latent image. When the electrostatic latent image was visualized on the ferroelectric element treated in this manner using a powder toner of positive polarity, the toner adhered only to the portion where the polarization was inverted. This toner image was transferred to plain paper and fixed to obtain a first arbitrary image.

Further, the ferroelectric element after the visible image was transferred to plain paper was heated and cooled, and development, transfer and fixing were repeated in the same manner as in the first sheet. At the stage, the surface of the ferroelectric element was scratched, toner adhered to the non-image area, and the image quality was significantly reduced.

Comparative Example 2 Barium metatitanate (Ba)
TiO ₃₎ ( "BT-02" of Sakai Chemical Industry Co., Ltd.) 50
%, Polyvinyl butyral (“BH-
3 ") A mixture consisting of 2.5% and 47.5% methyl ethyl ketone was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied on a nickel substrate using a bar coater so that the film thickness after drying was 98 μm, and was dried by heating at 60 ° C. for 3 hours.
This coating film was sintered at 1150 ° C. to obtain a ferroelectric element.

This ferroelectric element has a pulse width of 0.1
The alignment treatment was performed by applying a negative corona pulse having a voltage of 6 kV 50 times per second.

Through an arbitrary mask, a pulse width of 0.2
For 2 seconds, a positive corona pulse having a voltage of 6 kV was applied 100 times.
Next, the ferroelectric element was heated to 100 ° C. using a heater, and then developed using a powder toner of positive polarity on the cooled ferroelectric element, but no image was obtained.

Comparative Example 3 Lead Titanate (PbTiO ₃ )
A mixture consisting of 50% (manufactured by Soegawa Rikagaku Corporation), 2.5% of polyvinyl butyral (“BH-3” manufactured by Sekisui Chemical Co., Ltd.) and 47.5% of methyl ethyl ketone was dispersed and mixed by ball milling for 1 hour.

This dispersion mixture was applied on a nickel substrate using a bar coater so that the film thickness after drying was 98 μm, and then dried by heating at 60 ° C. for 3 hours.
This coating film was sintered at 1150 ° C. to obtain a ferroelectric element.

This ferroelectric element has a pulse width of 0.1
The alignment treatment was performed by applying a negative corona pulse having a voltage of 6 kV 50 times per second.

Through an arbitrary mask, a pulse width of 0.2
For 2 seconds, a positive corona pulse having a voltage of 6 kV was applied 100 times.
Next, the ferroelectric element was heated to 80 ° C. using a heater, and then developed on the cooled ferroelectric element using a powder toner of positive polarity, but no image was obtained.

[0198]

According to the image forming method using the ferroelectric element of the present invention, the latent image can be stably stored in a bright room for a long period, and the image can be written and erased as needed.

According to the image forming method using the ferroelectric element of the present invention, the contrast of the surface potential at the time of toner development is a difference between potentials having different polarities. It is possible to form a sheet toner image.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a ferroelectric element of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ferroelectric layer 2 Ferroelectric 3 Resin 4 Support layer

FIG. 2 shows a schematic sectional view of a ferroelectric element of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ferroelectric layer 2 Ferroelectric 3 Support layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshihiro Nishio 1-21-13-105, Negishi, Urawa-shi, Saitama (72) Inventor Hiroshi Komon 4-9-12, Minamiyukiya, Ota-ku, Tokyo (72) Inventor Hoshino Katsuyoshi 5-9-1-304 Onakadai, Inage-ku, Chiba-shi, Chiba

Claims (4)

[Claims] (1) A ferroelectric element having a ferroelectric layer containing a ferroelectric substance on a conductive support, in which ferroelectric dipoles in the ferroelectric layer are arranged in one direction. One step, (2) a second step of inverting the dipole in a part corresponding to an image part or a non-image part, and (3) uniform heating of the ferroelectric layer, followed by cooling to develop an electrostatic latent image The third step,
And (4) in the image forming method comprising a fourth step of developing with a toner the electrostatic latent image, a ferroelectric material used in the ferroelectric layer, the general formula (1) ## STR1 ## [(Bi ₂ O ₂ ) ²⁺ (XY ₂ O ₇ ) ^2- ] wherein X represents Sr, Pb or Na _0.5 Bi _0.5 , and Y represents Ta or Nb. Inorganic oxide ferroelectric or general formula (2) ## STR2 ## represented _{by] [X n Bi 4 Ti n} + 3 O 3n + 12] [ In the formula, X, Sr, Ba, Pb or Na _0.5 represents Bi _0.5 , and n represents 1 or 2. An image forming method using an inorganic oxide ferroelectric material represented by the formula: 2. The image forming method according to claim 1, wherein the ferroelectric layer is a ferroelectric sintered layer. 3. The image forming method according to claim 1, wherein the ferroelectric layer is a ferroelectric resin dispersion layer. 4. The image forming method according to claim 1, wherein the ferroelectric layer is a layer deposited on a substrate by electrodeposition from a mixed solution comprising a ferroelectric powder and a resin solution.