JPH054372A - Electrostatic recording device - Google Patents

Abstract

PURPOSE:To obtain a recording image having high resolution for a prolonged term by smoothly fluidizing a developer between a recording electrode and a counter electrode without compaction and preventing the fusion of the developer to the electrodes. CONSTITUTION:The surface layer 29b of a cylindrical electrode 29 is formed of an elastic material having surface hardness of 30 deg.-90 deg. (a JIS spring type measuring method) and a volume electric resistance value of 10<6>-10<11>(OMEGA.cm), a recording electrode, in which a slit is formed at the front end of a recording electrode sheet 17 faced oppositely to the cylindrical electrode 18, is formed, and the recording electrode is constituted so as to be held by a cushion member 28b. According to the constitution, even when a magnetic toner (d) intends to be consolidated between the electrodes by the swing of the cylindrical electrode 29 and the irregularities of the recording electrode, the recording electrode corresponding to the position of the consolidation is rocked, the cushion member 28b is deflected, the surface section 29b of the cylindrical electrode 29 is indented flexibly, and an interelectrode distance L between the recording electrode and the cylindrical electrode 29 is kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type electrostatic recording apparatus which forms an electrostatically recorded image without bringing a recording head and a recording medium into contact with each other.

[0002]

2. Description of the Related Art Conventionally, a multi-stylus printer is well known as one of electrostatic recording devices.
This multi-stylus printer forms a recording head by arranging a large number of needle-shaped electrodes (styluses) at equal minute intervals in the main scanning direction, and selectively applies a voltage to each needle-shaped electrode in accordance with a recording signal to print on the paper. Is directly discharged to form an electrostatic latent image. In this case, special paper coated with a high electric resistance agent is used so that the electric charge can be easily and stably retained on the paper. However, such a special paper has a poor writing property with a pencil or a pen, and is deteriorated depending on environmental conditions such as humidity.

If the distance between the tip of the needle-shaped electrode and the surface of the paper is large, the discharge electric field spreads and the dots formed become large, making it difficult to obtain a high-resolution recorded image. Therefore, a gap material is provided on the surface of the paper, and the gap material is brought into sliding contact with the tip of the needle electrode to secure a minute gap. However, according to this method, there is a problem that the tip of the needle-shaped electrode is worn.

Therefore, as an electrostatic recording system in which plain paper can be used and a minute gap between the recording medium and the tip of the recording electrode can be accurately secured, a toner image is formed on a drum-shaped intermediate recording medium, and A method of transferring a toner image onto a sheet is used. In the case of this method, the size of the apparatus tends to increase due to the use of the intermediate recording medium. Therefore, in general, a process of simultaneously performing recording and development is adopted to avoid the size increase of the apparatus. In this case, the recording electrodes are arranged in parallel in the width direction (main scanning direction) of the developer conveying path, and the developer is selectively transferred from the recording electrodes onto the surface of the counter electrode which also serves as an intermediate recording medium according to the recording information. There are many methods of forming images. In this method, it is required to keep the electrode facing distance between the recording electrode and the counter electrode constant over the entire width direction.

However, the counter electrode is usually formed in a drum shape and rotated in order to serve also as a recording medium. In that case,
The peripheral surface of the counter electrode tends to swing in the axial direction and the circumferential direction with the rotation. In addition, a minute convex portion may be formed on the surface of the developer transport path on which the recording electrode is installed. In that case, the recording electrode approaches the counter electrode by the height of the convex portion. In this way, a part where the electrode facing interval becomes narrower in the electrode facing part occurs, and when the developer is carried into the narrowed part, the density of the developer increases and the pressure between the electrodes is increased,
The developer appears to be compacted. As a result, the electric resistance value of the developer, which is usually about 1 × 10 ¹¹ [Ω], is reduced to 1 × 10 ³ to 1 × 10 ⁶ [Ω] in the consolidated portion, and the developer is transferred through the consolidated developer. Excessive leakage current flows,
Due to the energizing heat and the filling pressure, a serious problem may occur in which the developer is fused to the electrode. When the developer is fused to the electrodes, not only the resolution of the image is lowered but also the sharpness is lost.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and prevents abrasion of electrodes and fusion of toner onto recording electrodes, and provides high resolution and high quality recorded images for a long period of time. It is an object of the present invention to provide an electrostatic recording device that can be formed by the above method.

[0007]

SUMMARY OF THE INVENTION To achieve the above object, the present invention comprises a developer carrying member laid along a predetermined path, and a developer carrying means for carrying the developer along the surface of the developer carrying member. A plurality of recording electrodes arranged in parallel on the surface of the developer carrying member with a gap therebetween, and a counter electrode arranged with a required gap with respect to the recording electrodes. In the electrostatic recording device, which applies a voltage in accordance with the above, selectively transfers the developer carried along the surface of the developer carrying member to the counter electrode side, is involved in at least image formation of the recording electrode. The tip portions are individually swingably separated from each other, and at least a portion of the developer carrying member that supports the recording electrode tip portion is formed of an elastic material,
And at least a surface portion of the counter electrode facing the recording electrode is made of an elastic material, and at least a surface portion of the counter electrode facing the recording electrode is made of an elastic material, and at least an image of the recording electrode The point is that the tip portions involved in the formation are individually swingably separated, and at least the portion of the developer carrying member supporting the tip portion of the recording electrode is made of an elastic material.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below with reference to the drawings. First, referring to FIG. 1 to FIG.
An example will be described.

FIG. 1 is a schematic sectional view showing the overall construction of the electrostatic recording apparatus of the first embodiment. In the figure, reference numeral 1 denotes a paper feed cassette in which plain papers P are stacked and stored, and is attached to the side of the machine body so as to be freely inserted and removed. A paper feed roller 1a is disposed above the leading end of the mounted paper feed cassette 1 so as to be rotatable in the arrow direction. In front of the paper feed roller 1a, upper and lower transport guide plates 2a and 2b made of an insulating member are laid to form a paper carry-in path. A standby roll pair 3 is disposed in the sheet carry-in path, and the sheet P fed out by the sheet feed roller 1a is temporarily stopped from advancing to adjust the transport posture, and then transferred to the image transfer section T on the downstream side. Refeeding is performed in synchronization with the arrival timing of the recorded image described later.

At the image transfer portion T on the downstream side of the standby roll pair 3, a transfer charger 4 and a cylindrical electrode 5 which also serves as an image carrier are arranged to face each other. In this example, the cylindrical electrode 5 is indicated by an arrow "a".
Drive and rotate in the counterclockwise direction indicated by.

A recording image forming unit U, which will be described later, is installed opposite to the peripheral surface on the opposite side of the cylindrical electrode 5. A toner recording image is formed on the surface of the cylindrical electrode 5 by the recording image forming unit U, and the toner recording image is conveyed to the image transfer portion T as the cylindrical electrode 5 rotates, and is transferred onto the sheet fed again. The configuration of the recording image forming unit U will be described in detail later.

At the downstream side of the image transfer portion T, the tip of the separation claw 6 is arranged in pressure contact with the peripheral surface of the cylindrical electrode 5. An air suction type conveyor belt 7 is horizontally stretched on the downstream side of the separating claw 6, and the back surface of the sheet separated from the peripheral surface of the cylindrical electrode 5 by the separating claw 6 after the transfer of the recorded image is completed. While being sucked, it is conveyed toward the fixing device 8 provided in front of it. The fixing device 8 is composed of a heating roll 8a and a pressure contact roll 8b, and heat-fixes the toner image when the paper is sandwiched and conveyed between the rolls. Paper that has been fixed is
The sheets are discharged and stacked on the discharge tray 10 in a face-down state with the image surface facing down from the discharge port 9.

As described above, in the electrostatic recording apparatus of this embodiment, since the entire sheet conveying path from the sheet feeding to the sheet discharging is formed in a substantially straight shape, the sheet passing operation is generally smooth. Yes, it is difficult for image defects and paper passing defects such as jams to occur. In addition, there is an advantage that a face-down sheet discharge state that does not require page alignment, which is preferable for the recording apparatus, can be obtained through the straight sheet passage.

The detailed structure of the recording image forming unit U will be described below. As shown in FIG. 2, the recording image forming unit U is roughly composed of a developing / recording tank 12 having a recording means and a developer conveying means, and a developer storage tank 11 for storing a replenishment developer. A stirring blade 11a is rotatably arranged in the developer storage tank 11. In this example, the developer is a one-component developer containing at least an insulating resin, magnetic fine powder and colorant particles, and an insulating magnetic toner having a negative (−) triboelectrification polarity is used. A two-component developer in which a magnetic carrier and an insulating toner are mixed in a predetermined ratio can also be used as the developer.

At the bottom of the developing / recording tank 12, a horizontal circulation path 13 for the developer shown in FIG. 3 is formed. In the figure, in the pair of parallel longitudinal paths 13a and 13b in the horizontal circulation path 13, a pair of auger rolls 14a,
14b is rotatably installed. Each auger roll 14
The shafts 14a1 and 14b1 are provided with a plurality of screw blades 14a2 and 14a2 standing on the peripheral surfaces of the shafts 14a1 and 14b1 and reverse feed blades 14a3 and 14b3 having opposite screwing directions standing on one end of each shaft. (See Figure 5). Then, the auger rolls 14a, 14b are moved along the longitudinal paths 13a, 13b so that the respective reverse feed vanes 14a3, 14b3 are located on the opposite sides.
Place each inside. These pair of auger rolls 14a,
14b is driven and rotated in the directions opposite to each other as shown by arrows "b" and "c" and in the direction in which the developer is conveyed toward the reverse feed blades 14a3, 14b3. As a result, at the corners where the reverse feed vanes 14a3 and 14b3 are provided, the conveying forces in the opposite directions facing each other collide with each other, and the magnetic toner is ejected at a right angle and flows toward the other longitudinal path side. In this way, the magnetic toner is circulated and agitated in the direction shown by the broken line arrow "d" in this example, and at this time, the magnetic toner can be sufficiently tribocharged. By changing the material and shape of the auger rolls 14a and 14b, it is possible to sufficiently frictionally charge the developer with a necessary charge amount.

In the central portion of the horizontal circulation path 13 constructed as described above, the surrounding wall S is provided so that the circulating developer does not enter.
A space S surrounded by w is formed. Then, as shown in FIG. 2, the auger roll 14 closer to the developer storage tank 11 is provided.
A replenishment port 11b for the replenishment magnetic toner d _O is formed in the upper part of a along the axial direction of the auger roll 14a.

Above the other auger roll 14b, a developing sleeve 15 for vertically conveying the developer is installed horizontally. The developing sleeve 15 has a magnet rotor 16 rotatably incorporated therein, and has the cylindrical electrode 5 described above.
It is installed opposite to. Different magnetic poles are alternately magnetized on the peripheral surface of the magnet roll 16, and the magnetic toner d is driven and rotated in the counterclockwise direction indicated by an arrow "e" to transfer the magnetic toner d to the peripheral surface of the developing sleeve 15. The paper is conveyed in the clockwise direction indicated by the broken line arrow "F".

A doctor blade 12a for restricting the layer thickness of the magnetic toner d to an appropriate thickness is arranged near the peripheral surface of the developing sleeve 15 serving as a developer transport path and upstream of the developer transport direction "F". It is set up. A toner scattering prevention plate 12b is arranged above the doctor blade 12a. The toner scattering prevention plate 12b is provided to prevent the inconvenience that the developer conveyed downstream due to the layer thickness regulation by the doctor blade 12a scatters outside the recording image forming unit U and stains the image. In this example, the upper end of the tank wall of the developer recording tank 12 is bifurcated, and one of the doctor blades 1
2a, and the other is formed on the toner scattering prevention plate 12b.

A recording portion W on which a toner recording image is formed on the peripheral surface of the cylindrical electrode 5 is constructed as follows on the downstream side of the toner layer thickness regulating portion "F" in the toner conveying direction. FIG. 4 is a diagram for explaining the configuration of the recording section W in detail. As shown in FIG. 4, a portion of the peripheral portion of the developing sleeve 15 which is close to the peripheral surface of the cylindrical electrode 5 is horizontally cut off to form a flat portion 15a.
Are formed over the entire width direction of the developing sleeve 15. A cushion member 15b made of an elastic material is fixedly provided on the entire surface of the half area on the upstream side with respect to the toner transport direction "F" on the flat surface portion 15a. In this case, as the material of the cushion member 15b, an elastic material having an elastic coefficient E of 1 × 10 ⁶ ≦ E ≦ 3 × 10 ⁹ [N / m ² ] can be preferably used. This cushion member 1
The surface of 5b is formed as a circumferential surface having the same curvature so that the peripheral surface of the developing sleeve 15 is continuous. Therefore, the downstream end of the surface of the cushion member 15b comes to the position closest to the peripheral surface of the cylindrical electrode 5, and the step G is formed immediately downstream thereof.

The recording electrode sheet 17 is provided on the peripheral surface upstream of the developing sleeve 15 from the surface of the cushion member 15b.
Has been laid. In this case, the tip of the recording electrode sheet 17 is aligned with the end surface of the cushion member 15b forming the step G. The recording electrode sheet 17 of this example is composed of a flexible printed circuit board (FPC), and as shown in FIG.
A plurality of recording electrodes 17a extending parallel to each other in the sheet longitudinal direction along the circumferential surface of the developing sleeve 15 are provided on the base film 17b at a predetermined fine pitch in the sheet width direction (toner conveying path width direction: main scanning direction). It is arranged side by side. The number of recording electrode lines 17a corresponds to the maximum number of data for one main scanning line. In this example, a large number of recording electrode lines 17a made of a non-magnetic conductive material are patterned at a density of 84.6 μm pitch (300 DPI) with a gap of 40 μm.

An insulating coat 17c is applied to the surface of the recording electrode sheet 17 except the predetermined minute area Z from the tip of the recording electrode EL. As a result, the insulation between the recording electrode wires 17a can be ensured, and the abrasion of the recording electrodes 17a due to the friction with the magnetic toner can be prevented. The reason why the insulating coat 17c is not applied to the leading end of the recording electrode sheet 17 is as follows.

In the toner recording image, a recording voltage corresponding to the recording data is applied to the recording electrode wire 17a to form an electric field between the toner and the cylindrical electrode 5, and the toner charged by this electric field force is applied to the cylindrical electrode. It is formed by selectively transferring to the 5 side. However, if the insulating coat 17c is deposited on the surface of the recording electrode line 17a to which the recording voltage is applied, not only the necessary electric field cannot be efficiently formed, but also unnecessary charges are accumulated in the insulating coat 17c, and this unnecessary charge is accumulated. Causes image defects such as background stains and image distortion.
Therefore, as shown in FIG. 5, the leading end region Z related to the formation of the toner recording image on the recording electrode sheet 17 is set to the recording electrode EL.
The recording electrode wire 17a without applying the insulating coat 17c.
By exposing, it is possible to efficiently form a necessary electric field, and it is possible to reliably prevent generation of image defects such as scumming due to the above-mentioned unnecessary charges not accumulating.

As shown in FIGS. 6A and 6B, slits C are formed in the base film 17b between the recording electrodes EL, respectively. Each of these slits C is cut not only in the portion between the recording electrodes EL, but also in the base portion of the recording electrode EL coated with the insulating coat 17c. As a result, each recording electrode EL is separated from the recording electrodes EL on both sides and individually swingable in the thickness direction (vertical direction in (a) of the figure). By laying the tip end portion of the recording electrode sheet 17 thus constructed on the cushion member 15b as shown in FIG. 7A, the upper surface of the recording electrode EL and the cylindrical electrode 5 shown in FIG. The distance L between the electrodes and the peripheral surface can always be kept at a constant required minute distance. The mechanism will be described below based on (a) and (b) of FIG. In addition, (a) and (b) of the same figure are schematic three-dimensional surfaces of the recording unit W viewed from the downstream side in the toner conveying direction.

As shown in (b) of the same figure, a part of the peripheral surface of the cylindrical electrode 5 is swung to the recording electrode EL side from several μm to several + μm.
Even if it approaches to a certain degree, the cushion member 15b in the portion facing the magnetic toner d is bent accordingly and the recording electrode EL
Subsides and the inter-electrode distance L is maintained at a distance substantially the same as the required distance shown in FIG. This reliably prevents the magnetic toner d from being excessively compacted in the sway portion. As a result, the magnetic toner d is smoothly conveyed over the entire width direction of the electrode facing portion (recording portion W) without an overcurrent flowing through the compacted magnetic toner to generate heat and fuse the magnetic toner to the electrodes. A recorded image with high resolution can be stably formed.

Further, as shown in FIG. 8, even if a foreign substance r mixed in the magnetic toner d, a block of the magnetic toner d, or the like is conveyed to the electrode facing portion (recording portion W), the foreign substance r is removed from the cylindrical electrode. The recording electrode EL1 sandwiched between 5 and
Since the EL is separated from the EL by the slit C, the foreign matter r can be passed through by being largely bent separately from the EL. In this way, the inconvenience of solid matter such as foreign matter clogging the recording portion W is reliably prevented, and a high-quality recorded image can be formed more stably.

When the recording electrode sheet 17 having the above-described structure is manufactured, a base film 17b made of a flexible insulating material coated with a copper foil is subjected to an etching process to form a large number of recording electrode wires 17a in a pattern. Then, the insulating coat 17c is applied to the region excluding the tip end region Z to form the recording electrodes EL, and then the slit C may be cut between the recording electrodes EL.

In FIG. 2, the horizontal circulation path 13 described above is provided on the downstream side of the toner transport direction “F” of the recording section W.
Of the wall surrounding the central space S of the developer storage tank 11 side
The w1 is extended and its tip is brought into contact with the peripheral surface of the developing sleeve 15. As a result, the magnetic toner d ′ that has not been transferred in the recording portion W and remains on the peripheral surface of the developing sleeve 15 and has been conveyed along with the rotation of the magnet roll 16 is scraped off onto the replenishing tank path 13a of the horizontal circulation path 13, and the magnetic toner is discharged. This prevents the inconvenience that d ′ enters the central space S or is returned directly to the upstream side along the peripheral surface of the developing sleeve 15 without passing through the horizontal circulation path 13. The residual magnetic toner d ′ attached to the developing sleeve 15 separately from the peripheral wall of the central space S.
A dedicated flat plate member for scraping off may be provided. In this case, the scraping member may be supported in the vertical direction, the tip may be brought into contact with the peripheral surface of the developing sleeve 15, and the other end may be extended to the bottom of the central space S. If the scraping member is made of a magnetic material, the magnetic force of the magnet roll 16 can be blocked.
A smoother scraping and returning effect can be obtained.

As described above, the recording electrode sheet 17 having the recording electrode EL formed on the tip thereof is laid over the peripheral surface of about half of the developing sleeve 15, and is pulled out in the horizontal direction and then vertically lowered, as described above. It extends into the central space S of the horizontal circulation path. A plurality of drive circuit elements 17 'for applying a recording voltage to each recording electrode EL according to recording data are mounted on a vertically extending portion of the recording electrode sheet 17. Then, as shown in FIG. 5, the recording electrode lines 17a of the recording electrode sheet 17 described above are connected to each drive circuit element 17 'by dividing the recording electrode lines 17a into N lines. In this way, the recording electrode sheet 1
The other end portion on which the drive circuit element 17 'of No. 7 is mounted is attached to the central space S
By being installed inside, the drive circuit element 17 'can be protected from dust such as developer, and the structure of the developing recording tank 12 can be made extremely compact.

Next, a recording image forming operation in the electrostatic recording apparatus of this example will be described. In FIG. 2, when the magnet roll 16 is driven and rotated in the direction of the arrow "e", a rotating magnetic field for rotating the particles of the magnetic toner d is formed on the outer peripheral surface of the developing sleeve 15, and the magnetic toner d forms ears. Meanwhile, the magnetic roll 16 is conveyed in the arrow “F” direction opposite to the rotating direction. The magnetic toner d conveyed is
The doctor blade 12a reaches the recording portion W after the cutting is regulated to a predetermined thickness. At this time, the magnetic toner d is negatively charged by friction between the magnetic toners and the peripheral surface of the developing sleeve 15. In the recording unit W, (a) of FIG.
As shown in FIG. 3, a large number of recording electrodes EL are laid in parallel. For each recording electrode EL, the drive circuit element 1 is formed as described above.
7'selectively applies a recording voltage according to recording data. In this case, in FIG. 7A, when the 1-bit recording data is, for example, “H”, the corresponding recording electrode EL
Since a voltage of −200 V is applied to the cylindrical electrode 5 and a voltage of −50 V is applied to the cylindrical electrode 5 facing the recording electrode EL by the bias power source 5a, a potential difference of 150 V is formed from the cylindrical electrode 5 to the recording electrode EL. To be done. Since the negatively charged magnetic toner d moves to a higher potential, −20
Only the magnetic toner d on the recording electrode EL to which a voltage of 0V is applied is selectively transferred to the surface of the cylindrical electrode 5 to form one black dot.

On the other hand, when the 1-bit recording data is "L", the recording electrode EL is at the ground potential. As a result, the potential difference when the corresponding recording electrode EL is seen from the cylindrical electrode 5 is −50 V.
Therefore, the negative magnetic toner d remains held on the recording electrode EL side and does not transfer.

As described above, the potential of each recording electrode EL is selectively controlled to -200 V and the ground potential according to the input recording data, and the toner recording image according to the recording data is formed on the surface of the corresponding cylindrical electrode 5. To be done. In this case, each recording electrode E
A slit C is cut between L to separate each recording electrode EL so as to be swingable in the thickness direction.
Since L is supported by the cushion member 15b, as described above, the upper surface of the recording electrode EL in the recording portion W and the cylindrical electrode 5 are
The inter-electrode distance L between the peripheral surfaces can always be kept constant at a necessary minute distance. As a result, the magnetic toner d smoothly moves to the recording portion W.
While being transported, the inconvenience that the magnetic toner is compacted in the recording portion W and melted and adhered to the electrode is surely prevented. Therefore, a high-resolution and high-quality toner recording image can be stably formed on the peripheral surface of the cylindrical electrode 5.

Further, as shown in FIG. 4, since the step G is formed on the downstream side of the recording portion W, the magnetic toner d'which is not used for image formation and remains on the developing sleeve 15 is recorded. Immediately after passing through the portion W, it moves away from the surface of the cylindrical electrode 5. Therefore,
The problem that the toner recording image formed on the surface of the cylindrical electrode 5 in the recording portion W is disturbed by mutual interference with the residual magnetic toner d'is surely avoided.

Further, as shown in FIG. 6A, since the recording electrode EL is exposed without being covered with the insulating coat 17c, unnecessary charges are not accumulated on the recording electrode EL. Therefore, the background stain due to unnecessary electric charges and the voltage leak phenomenon between the recording electrodes are prevented, and a clear toner recorded image with high resolution and high density can be stably formed.

In FIG. 1, the toner recording image formed on the surface of the cylindrical electrode 5 is conveyed to the image transfer portion T with the rotation of the cylindrical electrode 5 in the counterclockwise direction "a" as shown in FIG. It is transferred onto the re-fed paper by measuring the timing with Pair 3. The bias voltage of the bias power source 5a may be changed to adjust the density of the toner recording image. In that case, the appropriate adjustment range is 0
It is about -50V, and the closer to 0V, the higher the image density.

In FIG. 2, the magnetic toner d ′ remaining without being transferred to the cylindrical electrode 5 side in the recording section W moves to the downstream side as the magnet roll 16 rotates, and is scraped from the surface of the developing sleeve 15 by the scraping section Sw1. taken, it is stirred and mixed with the magnetic toner d _o to be supplied from the supply port 11 to fall into the auger roll 14a.

With the rotation of the auger roll 14a, the residual magnetic toner d'returned and returned and the replenishing magnetic toner d _O are mixed and stirred and circulated and conveyed. In FIG. 3, the magnetic toner that is circulated and conveyed in the direction of the dashed arrow "d" is again conveyed in the vertical direction by the rotating magnetic field of the magnet roll 16 that extends above when it is conveyed in the longitudinal path 13b on the opposite side. Be transported.

As described above, in the recording portion W, the cylindrical electrode 5
Of the residual magnetic toner d ′ that has been transferred to the downstream side without being transferred to the side
Is scraped off onto the horizontal circulation path 13, and is smoothly returned to the upstream side while being agitated through this horizontal circulation path 13,
It is again used for forming a toner recording image. In this case, the magnetic toner d before being conveyed in the vertical direction is not transferred to the developing sleeve 15
The developing sleeve 1 is always agitated and conveyed along the axial direction (width direction of the toner conveyance path: main scanning direction).
It is supplied uniformly over the entire width direction of the surface of five circumferences. Therefore,
On the peripheral surface of the developing sleeve 15, the magnetic toner d is always carried uniformly over the entire widthwise direction thereof and is conveyed to the recording portion W, so that a good recorded image having a uniform image density can be stably obtained. Become. Further, the magnetic toner d is transferred to the horizontal circulation path 13
When the toner is circulated and conveyed while being stirred, the magnetic toner particles rub against each other, and the magnetic toner is sufficiently frictionally charged.

Next, a second embodiment of the present invention will be described with reference to FIGS. 9 to 11. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. The electrostatic recording apparatus according to the present embodiment differs from that according to the first embodiment in that the structure of the cylindrical electrode and the slit C and the cushion member provided at the tip of the recording electrode sheet are not used. First, the cylindrical electrode will be described. Although the cylindrical electrode 5 used in the first embodiment is entirely made of metal, the cylindrical electrode 18 of this embodiment has a conductive material such as metal as shown in FIG. The difference is that a conductive surface layer 18b made of an elastic material is deposited on the peripheral surface of a raw material pipe 18a made of a material. As the elastic material forming the surface layer 18b, the surface hardness Hs is H by JIS spring type measurement method.
s = 30 ° to 90 °, and its volume electric resistance value (specific resistance) is 1 × 10 in order to have an effect as a counter electrode.
An elastic material having each characteristic of ⁶ to 1 × 10 ¹¹ [Ω · cm] is selected and used. Further, the cylindrical electrode 18 of this example has a surface hardness H on the peripheral surface of the stainless steel tube 18a.
s is 90 ° and volume electric resistance is 1 × 10 ¹¹ [Ω · cm]
The conductive urethane rubber surface layer 18b is coated.
In this way, by forming the cylindrical electrode 18 into a soft roll whose surface layer 18b flexes flexibly in response to external pressure, an inter-electrode distance L (see FIGS. 10 and 11) described below is always kept constant at a necessary minute distance. be able to. As a result, fusion of the developer on the electrode surface is prevented, and a high-resolution recorded image can be stably formed. The action and effect will be described later in detail. The cylindrical electrode 18 configured as described above is driven and rotated in the counterclockwise direction indicated by the arrow "a" also in this example.

Another structure different from the first embodiment is that the cushion member provided on the developing sleeve 15 is not used and the slit C is formed in the recording electrode sheet 17 (recording electrode EL). Is not. In other words, as shown in FIG. 9, the step G is only formed at the position closest to the cylindrical electrode 18 side on the peripheral surface of the developing sleeve 15. The size (drop) of the step G is about 10 times the gap L between the surface of the recording electrode EL and the circumferential surface of the cylindrical electrode 18, and the step G having such a drop is the developing sleeve 15 in this example. It is formed over the entire width direction of the peripheral surface. With this configuration, the recording unit W of this embodiment has the configuration shown in FIG. 10 when viewed from the downstream side in the toner transport direction.

As in the above-described embodiment, a recording electrode sheet 17 having a large number of recording electrodes 17a is attached and laid on the peripheral surface of the developing sleeve 15 upstream from the step G. As shown in FIG. 5, a large number of recording electrode wires 17a extend along the circumferential direction of the peripheral surface of the developing sleeve 15 and extend parallel to each other in the sheet longitudinal direction, and at a predetermined fine pitch in the sheet width direction. (Toner transport path width direction: main scanning direction).

Next, a recording image forming operation in the electrostatic recording apparatus of this embodiment will be described. Similar to the first embodiment, when the magnet roll 16 is driven and rotated in the direction of the arrow "e", a rotating magnetic field for rotating the particles of the magnetic toner d is formed on the outer peripheral surface of the developing sleeve 15, as shown in FIG. As shown in FIG. 3, the magnetic toner d is conveyed in the arrow “F” direction opposite to the rotation direction of the magnet roll 16 while forming the ears, and reaches the recording portion W.

In the recording section W, as shown in FIG. 10 described above, a large number of recording electrodes EL are laid in parallel. For each of these recording electrodes EL, the drive circuit element 17 'converts the recording data in the same manner as described above. Accordingly, the recording voltage is selectively applied. Therefore, 1
When the bit recording data is, for example, “H”, a voltage of −200 V is applied to the corresponding recording electrode EL, and the cylindrical electrode 1
Since the bias power supply 18c applies a voltage of -50V to the magnetic disk 8, the magnetic toner d charged negatively based on the potential difference of 150V is the same as the cylindrical electrode 1 having a high electric potential.
8 to form black dots on the peripheral surface of the cylindrical electrode 18.

On the other hand, when the 1-bit recording data is "L", the recording electrode EL becomes the ground potential, and the negative polarity magnetic toner d is retained on the recording electrode EL side and does not transfer.
In this way, a toner image corresponding to the input recording data is formed on the peripheral surface of the cylindrical electrode 18, but in the electrostatic recording apparatus of this example, the surface layer 18b of the cylindrical electrode 18 has a required surface hardness. It is formed of urethane rubber which is an elastic material having an electric resistance value. Thereby, the inter-electrode distance L between the upper surface of the recording electrode EL and the peripheral surface of the cylindrical electrode 18 in the recording portion W is
It can be kept constant at a necessary minute distance. That is, FIG.
As shown in FIG. 1, even if the projection A is formed on the recording electrode sheet 17 for some reason and the inter-electrode distance L between the recording electrode EL and the cylindrical electrode 18 is partially reduced (in the example of FIG. When the EL approaches the circumferential surface of the cylindrical electrode 18 by several μm to several tens of μm, for example, the surface layer 18b of the cylindrical electrode 18 bends inward, and the electrode between the upper surface of the recording electrode EL in the recording section W and the circumferential surface of the cylindrical electrode 18 The distance L can always be kept constant at a necessary minute distance. On the contrary, the cylindrical electrode 18 swings,
A part of the peripheral surface may approach the recording electrode side, but similarly the surface layer 18b can be flexibly dented and the interelectrode distance L can be made constant. As a result, the magnetic toner d is smoothly conveyed through the recording portion W, and an excessive leak current flows through the compacted magnetic toner to damage the electrode, or the magnetic toner melts and adheres to the electrode. A high-resolution, high-quality toner-recorded image can be stably formed on the circumferential surface of the cylindrical electrode 18.

Also in this embodiment, since the recording electrode EL is exposed without being covered with the insulating coat 17c, unnecessary electric charges are not accumulated on the recording electrode EL, and scumming due to unnecessary electric charges or between recording electrodes is caused. As in the first embodiment, the voltage leak phenomenon is prevented and a clear toner recording image with high resolution and high density can be stably formed.

Further, the toner image formed on the cylindrical electrode 18 as described above is moved to the image transfer portion T by the cylindrical electrode 18 rotating in the "a" direction as in the above-described embodiment, and is transferred to the transfer charger 4. Is transferred to a sheet conveyed by. Also,
The magnetic toner d ′ remaining on the developing sleeve 15 is scraped off by the scraping unit Sw1, drops on the auger roll 14a, and is stirred and mixed with the magnetic toner d _o to be used for new image formation.

Here, the results of a comparative experiment in which an image is actually formed by changing the material and structure of the surface layer 18b of the cylindrical electrode 18 within a range satisfying the conditions of the surface hardness and the volume electric resistance value described above will be described.

First, as in the case of the above example, the cylindrical electrode 1
As described in the description of the structure of No. 8, the surface layer 18b has a surface hardness Hs of 90 ° and a volume electric resistance value of 1 × 10 ¹¹ [Ω · c.
m] of the conductive urethane rubber. This cylindrical electrode 1
Even when 8 is attached to the electrostatic recording apparatus shown in FIG. 1 and recording image formation (printing) is repeated 10,000 times, a good image quality without image defects such as white stripes can be stably obtained. It was

Next, the surface hardness Hs of the surface layer 18b is 30.
A cylindrical electrode 18 made of conductive silicone rubber having a volume electric resistance value of 1 × 10 ⁷ [Ω · cm] at a temperature of 0 ° was attached to the electrostatic recording apparatus of FIG. 1 and printing was repeated 10,000 times in the same manner. It was possible to stably obtain good image quality without image defects such as white stripes.

Further, the surface layer 18b is referred to as a first surface layer and a second surface layer.
It has a two-layer structure in which the first surface layer is a volume layer
Electric resistance is 1 × 10¹¹~ 1 x 10¹²[Ω · cm]
The volume resistivity of the second surface layer is made of rilurethane rubber.
Is 1 × 10⁶[Ω · cm] nitrile rubber (NBR)
Each of them is formed, and the volume electric resistance value of the entire surface layer is 1 × 10. ⁶
A cylindrical electrode 18 having a surface hardness Hs of 60 ° at [Ω · cm]
Configured. This cylindrical electrode 18 is installed in the electrostatic recording device of FIG.
And then repeated 10,000 prints in the same way
Stable image quality with no image defects such as white lines
I was able to get it. From the above, the range that satisfies the above conditions
By changing the surface hardness and volume electric resistance of the surface layer 18b
Being able to obtain stable images when printed
I was able to confirm.

Next, a third embodiment of the present invention will be described with reference to FIGS. 12 and 13. In the description of the present embodiment, the same components as those in the first and second embodiments described above are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, similarly to the first embodiment, the slit C is formed in the recording electrode sheet (recording electrode EL), and the cushion member is arranged. It is configured to have a surface layer using the conductive elastic member described in the second embodiment.

Specifically, as shown in FIG. 12, a portion of the peripheral portion of the developing sleeve 28 close to the peripheral surface of the cylindrical electrode 28 is cut off so as to form a predetermined step G, and the flat portion 28a is formed on the developing sleeve 28. Is formed over the entire area in the width direction of the cushion member 28b made of an elastic material on the front surface of the half area on the upstream side with respect to the toner transport direction "F" on the flat surface portion 28a.
Is provided. In this case, as the material of the cushion member 28b, a material having an elastic coefficient E within the range of 1 × 10 ⁶ ≦ E ≦ 3 × 10 ⁹ [N / m ² ] is used as in the first embodiment. . The surface of the cushion member 28b is formed as a circumferential surface having the same curvature so that the circumferential surface of the developing sleeve 28 is continuous, and the circumferential surface of the developing sleeve 28 upstream from the step G has A recording electrode sheet 17 having a large number of recording electrodes is adhered and laid as in the embodiment. A large number of recording electrode wires 17a are arranged in parallel on the recording electrode sheet 17 at a predetermined fine pitch, and an insulating coat 17c is attached to the surface of the recording electrode sheet 17.

Further, similar to the first embodiment described above, slits C are cut in the base film 17b between the recording electrodes EL, and the recording electrodes EL are cut off from the recording electrodes EL on both sides, respectively. It has a swingable structure.

On the other hand, as shown in FIG. 12, the cylindrical electrode 29 is constructed by depositing a surface layer 29b made of an elastic material on the peripheral surface of a raw tube 29a made of a conductive material such as metal. The surface hardness Hs of 29b is Hs = 30 ° -9.
It is 0 ° and the volume electric resistance value (specific resistance) is 1 × 10.
An elastic material having a characteristic of ⁶ to 1 × 10 ¹¹ [Ω · cm] is used. Specifically, the cylindrical electrode 29 of the present example has a surface hardness Hs of 90 ° and a volume electric resistance value of 1 × 1 on the peripheral surface of a stainless steel tube 29a as in the second embodiment.
Surface layer 19b of 0 ¹¹ [Ω · cm] conductive urethane rubber
Use the one that has been attached.

Next, a recording image forming operation in the electrostatic recording apparatus of this embodiment will be described. As shown in FIG. 12, when the magnet roll 16 is driven and rotated in the direction of the arrow "e", a rotating magnetic field for rotating the particles of the magnetic toner d is formed on the outer peripheral surface of the developing sleeve 28. Similarly, the magnetic toner d is conveyed in the arrow “F” direction opposite to the rotation direction of the magnet roll 16 and reaches the recording unit W. A large number of recording electrodes EL are laid in parallel in the recording portion W as shown in FIG. 13, and a recording voltage according to recording data is selectively applied to each of the recording electrodes EL. Therefore, when the 1-bit recording data is, for example, "H", a voltage of -200 V is applied to the corresponding recording electrode EL, and the negatively charged magnetic toner d is transferred to the surface of the cylindrical electrode 29, as in the above-described embodiment. Then, a black dot is formed. On the other hand, when the 1-bit recording data is "L", the recording electrode EL is at the ground potential, and the magnetic toner d is retained on the recording electrode EL side and does not transfer.

In this way, a toner recording image corresponding to the recording data is formed on the surface of the cylindrical electrode 29. At this time, in this example, the surface layer 29b of the cylindrical electrode 29 is made of an elastic material having the above-mentioned surface hardness and electric resistance. In addition, the recording electrode sheet 17 and the recording electrode EL are divided by a slit C, and a cushion member 28b is disposed below the recording electrode EL. Therefore, for example, when a foreign substance is mixed in the magnetic toner d or a block of the magnetic toner d is conveyed to the recording unit W, the recording electrode EL at the position sandwiching the foreign substance or the like with the cylindrical electrode 29 is the surface of the paper. It can be greatly bent downward to allow foreign matters to pass through. That is, in such a case, it is possible to prevent the inconvenience that the recording portion W is clogged with foreign matter or the like. Further, even if there is a portion where the inter-electrode distance L is narrow because, for example, the developing sleeve 28 or a part of the cylindrical electrode 29 is deformed, as shown in FIG. Since the recording electrode EL at the corresponding position bends downward and the surface layer 29b of the cylindrical electrode 29 flexes flexibly inward, the interelectrode distance L can be kept constant at a predetermined minute distance. Further, for example, even when the axial distance between the developing sleeve 28 and the cylindrical electrode 29 is deviated due to wear, aging, or the like, the recording electrode EL is similarly operated.
The interval L can be kept constant by the swinging of the cushion member 28b, the bending of the cushion member 28b, and the bending of the surface layer 29b. Therefore, also in the electrostatic recording apparatus of the present embodiment, the compacted magnetic toner is not formed, it is possible to prevent the damage of the electrode due to the leak current or the like and the fusion of the developer to the electrode surface, and it is possible to obtain the high resolution. A recorded image can be stably formed.

The toner image thus stably formed on the cylindrical electrode 29 is moved to the image transfer portion T by the rotation of the cylindrical electrode 29, and is transferred onto the sheet as described above. Further, the magnetic toner d ′ remaining on the developing sleeve 28 is
After passing through the recording portion W, it is moved away from the cylindrical electrode 29 due to the step G, is accommodated in the developing recording layer 12, and is used for new image formation.

Next, some other embodiments of the present invention will be described with reference to FIGS. 14 to 16. The same components as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

The fourth embodiment shown in FIG. 14 employs a coil carrying member 19 for generating a traveling wave magnetic field by an exciting coil instead of a magnet roll as the developer carrying means.
The developer transport path is formed in a non-circular path. The coil carrying member 19 has a large number of grooves 2 extending parallel to the width direction on the outer periphery of a base body 20 formed of a magnetic material having a non-circular cross section.
0a is recessed, and a conductor wire is wound around each groove 20a to form the exciting coil 21. This exciting coil 21
Is divided into n groups, and an alternating current whose phase is shifted by π / n is applied to each group, a traveling wave magnetic field that advances in the arrow “T” direction is generated along the outer peripheral surface of the coil conveying member 19. The recording electrode sheet 17 having the same structure as that of the above-mentioned embodiment is laid on the outer peripheral surface of the coil conveying member 19, one end of the recording electrode sheet 17 is drawn into the base body 20, and the recording electrode drive circuit element 17 'is mounted. Since the developer carrying means by the coil carrying member 19 of the present example does not use a rotating member, the durability of the device is improved, and the developer carrying path can be freely set, which greatly promotes downsizing of the device. Is possible.

Next, in a fifth embodiment shown in FIG. 15, a pair of magnet rolls 22 and 22 are used as the developer conveying means, and the developer is carried in an elliptical shape by the cooperation of the rotating magnetic fields of the two. 23 is conveyed along the surface in the direction of arrow "H". In this case as well, one end of the recording electrode electrode sheet 17 having the same configuration, which becomes the recording electrode, is installed along the surface of the developer carrying member 23, and the other end is pulled into the developer carrying member 23 to drive the recording electrode. Circuit element 1
It has a 7 '.

Further, in the sixth embodiment shown in FIG. 16, the magnet roll 25 is arranged inside the developing sleeve 24, one end of the recording electrode sheet 26 is laid on the peripheral surface of the developing sleeve 24, and the other end is arranged. A drive circuit element 17 'extending to the outside of the developing sleeve 24 and having a recording electrode protruding is mounted on the end thereof. In this case, a plurality of openings 26a are formed along the width direction of the recording electrode sheet 26 so as not to prevent the developer carrying member from advancing.

As described above, in any of the fourth to sixth embodiments described above, as described in the first to third embodiments, the distance between the electrodes is always kept constant and the high resolution is obtained. Similarly, it is possible to stably form a high-quality and high-quality recorded image.

Furthermore, the present invention should not be limited to the above-mentioned first to sixth embodiments, and various modifications can be made within the technical scope of the present invention. For example, in FIG. 7A, if the base film 17b carrying the recording electrode EL is formed of a highly elastic member, the recording electrode EL can be swung more sharply following the deflection of the counter electrode. it can.
In this case, if the base film 17b has the required elasticity, the cushion member 15b can be omitted. Further, when the recording electrode wire having the tip portion as the recording electrode EL is directly laid on the developer carrying member, it is not necessary to individually separate the tip portion of each recording electrode wire so as to be swingable. In this case, by making a cut in the portion of the developer carrying member that supports the recording electrodes, each recording electrode EL can be swung with greater sensitivity. Further, although the toner having the negative (−) chargeability is used as the toner shown in FIG. 2, it is also possible to use the toner having the positive (+) chargeability. In that case, the bias voltage applied to the recording electrode and the counter electrode may be positive (+) polarity.

[0063]

As described above in detail, according to the present invention, the developer is conveyed along the surface of the developer carrying member, and a plurality of recording electrodes are formed on the surface of the developer carrying member with respect to the counter electrode. By laying them in parallel with a gap between them, separating the recording electrodes individually so that they can swing, and by supporting the recording electrodes with an elastic material, the distance between the recording electrodes and the counter electrode is always maintained. It can be kept constant at the necessary minute intervals. As a result, the developer is compacted between the electrodes and the electric resistance value of the developer is reduced, which prevents the inconvenience that overcurrent flows and heat is generated, and the pressure when the developer is energized and between the electrodes is reduced. Therefore, there is no possibility of melting and adhering to the electrode.

Further, since the electrostatic recording apparatus of the present invention is a non-contact recording system, there is no fear that the recording electrodes will be worn. Therefore, the durability of the recording head is improved, the developer is smoothly conveyed between the electrodes kept in a constant gap, and a high-resolution, high-quality recorded image can be stably formed for a long period of time.

Further, according to the present invention, at least the surface portion of the counter electrode is made of an elastic material having required surface hardness and volume electric resistance, so that either one of the recording electrode and the counter electrode is a developer. Even if you try to get closer to the other side with
In response to this, the surface portion of the counter electrode flexes flexibly, and the distance between the recording electrode and the counter electrode can always be kept constant at a necessary minute distance.

Further, the developer is always smoothly transported between the electrodes kept at a constant gap, and a high-resolution and high-quality recorded image can be stably formed for a long period without image defects such as white stripes. .

Further, since the opposing electrodes are individually swingable and the cylindrical electrode is also made of an elastic member, it is possible to reliably prevent the generation of compacted toner due to the synergistic effect of the two, and it is possible to further improve the quality. A recorded image can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the overall configuration of an electrostatic recording device according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a recording image forming unit and its peripheral configuration in the electrostatic recording apparatus.

FIG. 3 is a plan sectional view showing a horizontal circulation path of the recording image forming unit.

FIG. 4 is a schematic cross-sectional view showing a configuration of a recording unit and a cylindrical electrode in the electrostatic recording device.

FIG. 5 is a perspective view showing the entire recording image forming unit.

FIG. 6 is an enlarged perspective view and a plan view of a recording unit.

FIG. 7 is a schematic elevation view showing the recording unit and a schematic elevation view showing the operation.

FIG. 8 is a schematic elevational view showing the operation of the recording unit.

FIG. 9 is a configuration diagram of a recording unit and a cylindrical electrode according to a second embodiment of the present invention.

FIG. 10 is a schematic elevational view showing a recording unit of the second embodiment.

FIG. 11 is a schematic elevational view showing the operation of the second embodiment.

FIG. 12 is a configuration diagram of a recording unit and a cylindrical electrode showing a third embodiment of the present invention.

FIG. 13 is a schematic elevational view showing a recording unit of the third embodiment.

FIG. 14 is a perspective view showing an entire recording image forming unit of an electrostatic recording device according to a fourth exemplary embodiment of the present invention.

FIG. 15 is a perspective view showing the entire recorded image forming unit of the electrostatic recording apparatus according to the fifth embodiment of the present invention.

FIG. 16 is a perspective view showing the entire recorded image forming unit of the electrostatic recording apparatus according to the sixth embodiment of the present invention.

[Explanation of symbols] 4 Transfer charger 5, 18, 29 Cylindrical electrode 18a, 29a Tube 18b, 29b surface layer 5c, 18c Bias power supply (cylindrical electrode side) 11 developer storage tank 12 Development recording tank 13 Horizontal circulation path 14a, 14b auger roll 15, 24, 28 Development sleeve 16,22,25 magnet roll 17,26 Recording electrode sheet 17a recording electrode wire 17c Insulation coat 17 'drive circuit element 19 Coil transfer member 21 Excitation coil EL recording electrode G step S central space U Record image forming unit W recording section

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tadao Yamamoto             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office (72) Inventor Hideaki Inoue             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office (72) Inventor Yasuto Sato             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office (72) Inventor Hideki Takahashi             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office (72) Inventor Toshiro Honda             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office (72) Inventor Kenichiro Asako             2-229 Sakuragaoka, Higashiyamato-shi, Tokyo             Shio Computer Co., Ltd. Tokyo office

Claims (5)

[Claims] 1. A developer carrying member laid along a predetermined path, a developer carrying means for carrying a developer along the surface of the developer carrying member, and a developer on the surface of the developer carrying member. It has a plurality of recording electrodes extended along the agent transport direction and a counter electrode arranged with a required gap with respect to the recording electrodes, and a voltage is applied to each of the recording electrodes according to recording information. In an electrostatic recording device that selectively transfers the developer carried along the surface of the developer carrying member to the counter electrode side, at least the tip ends of the recording electrodes involved in image formation are shaken individually. An electrostatic recording apparatus characterized in that it is movably separated and at least a portion of the developer carrying member that supports the recording electrode tip is made of an elastic material. 2. A developer carrying member laid along a predetermined path, a developer carrying means for carrying the developer along the surface of the developer carrying member, and a gap on the surface of the developer carrying member. A plurality of recording electrodes arranged in parallel with each other and a counter electrode arranged with a required gap with respect to the recording electrodes, and a voltage is applied to each of the recording electrodes according to recording information, In an electrostatic recording device for selectively transferring the developer conveyed along the surface of a carrying member to the counter electrode side,
An electrostatic recording apparatus, wherein at least a surface portion of the counter electrode facing the recording electrode is formed of an elastic material. 3. A developer carrying member laid along a predetermined path, a developer carrying means for carrying the developer along the surface of the developer carrying member, and a gap on the surface of the developer carrying member. A plurality of recording electrodes arranged in parallel with each other and a counter electrode arranged with a required gap with respect to the recording electrodes, and a voltage is applied between each of the recording electrodes and the counter electrode according to recording information. In the electrostatic recording device that selectively transfers the developer carried along the surface of the developer carrying member to the counter electrode side, at least the surface portion of the counter electrode facing the recording electrode is made of an elastic material. And at least the tips of the recording electrodes involved in image formation are individually swingably separated from each other, and at least the portions of the developer carrying member supporting the tips of the recording electrodes are made of an elastic material. Characterized by Electronic recording device. 4. The electrostatic recording apparatus according to claim 1, wherein the elastic coefficient E of the elastic material is 1 × 10 ⁶ ≦ E ≦ 3 × 10 ⁹ [N / m ² ]. 5. The volume electric resistance value R of the surface portion of the counter electrode.
Is 1 × 10 ⁶ ≦ R ≦ 1 × 10 ¹¹ [Ω · cm], The electrostatic recording device according to claim 2 or 3.