JPH03234674A - Electrostatic recording device - Google Patents

Abstract

PURPOSE:To present a recording speed changeable electrostatic recording device by a method wherein by using a recording device which extracts ion from an ion generating device conforming to recording signals, on a moving speed changeable solid dielectric recording medium, an electrostatic pattern is formed. CONSTITUTION:For an electrostatic recording device 20, around a recording medium drum 23 for which a dielectric layer 22 is provided on a grounded electrically conductive body 21, an ion recording head 24, non-contact type single component non-magnetic developing apparatus 25, toner transfer apparatus 26, cleaning blade 27 and a static eliminator 28 are provided. A recording signal which is modulated at the transmitting side enters a receiving unit of a facsimile on the receiving side through a transmitting passage, and is demodulated by a demodulator 29, and is stored in a buffer memory 30. By control by a control unit 31, an ion memory head driving circuit 32 is operated conforming to the stored memory signal, and on the surface of the dielectric layer 22 which passes through the ion recording head 24, a charge pattern is formed by ion which is extracted from the ion recording head 24 conforming to a recording signal. The charge pattern is developed by the developing apparatus 25 with a dry developing agent of which polarity is opposite to that of the charge pattern, and is made visual.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to an electrostatic recording device for forming and visualizing an electrostatic pattern, and particularly relates to an electrostatic recording device suitable for facsimile.

(Prior Art) The facsimile is showing remarkable popularity as an information communication device. The receiving section (recording section) of a facsimile uses a thermal recording printer that uses thermal paper, an electrostatic recording printer that uses electrostatic recording paper, or an electrophotographic laser printer that uses plain paper. Thermal recording printers record by using a special recording paper called thermal paper that directly develops color using a thermal head, so they can record at any time, have excellent maintainability and reliability, and are widely used in popular facsimile machines. Electrostatic recording printers apply a high voltage according to the recording signal between a special recording paper with an insulating surface and a recording stylus, and ions generated by air gap breakdown form an electrostatic pattern on the insulating surface of the recording paper. However, this is visualized using a developer and recorded, and it is excellent in high speed and can be recorded at any time. A laser printer is a plain paper recording method that forms an electrostatic pattern by optically writing on a uniformly charged photoconductive intermediate medium in accordance with a recording signal, and then visualizes this using a developer to record.・Excellent high speed,
Applied to high-performance facsimiles. In the facsimile machine on the sending side, the original is read by the reading input unit, converted into binary data, and recorded at the output unit of the facsimile machine on the receiving side via a communication circuit. If there is a wide margin in a document, the signal for that portion is compressed and transmitted in order to increase communication efficiency, and in the receiving section, the recording paper is fed faster than the recording section for the portion corresponding to the margin. In this way, facsimiles generally record intermittently. Conventional facsimile machines will be able to mix and exchange not only characters or binary images, but also code signals and nature-like Ija images. In such a case, it is expected that the processing time will be different in order to record signals in various modes at the receiver, and in order to record such mixed signals, intermittent recording is required. . Furthermore, as communication networks become more sophisticated, it is required to output high-speed, high-quality records. Facsimiles are expected to be used not only as communication devices, but also as office equipment used in a wide range of offices, and even as complex information input/output devices used in general households. The ability to record on paper is required.

Future facsimile machines will require a receiving unit that can record on plain paper at high speed and at any time. Laser printers are attracting attention in response to these demands, but they often have problems with recording performance. FIG. 11 shows the basic configuration of a receiving section using a laser printer as an output device. 1 is a photosensitive drum, and a photosensitive layer 3 made of an inorganic photoconductive material such as Se or an organic photoconductive material is provided on a conductive sleeve 2. Surrounding the photosensitive drum 1 are a charging corona charger 4, a developing device 5 such as a two-component magnetic brush developing device or a developing device using non-magnetic component toner, a transfer corona charger 6, a blade cleaning 7, and a light source for charge removal. 8 is placed. The recording signal modulated on the transmitting side enters the receiving section of the receiving side facsimile via the transmission line, is demodulated by the demodulator IO, and is stored in the page memory 12 under the control of the control section U. After the recording signals for one page are stored, the recording signals are sent in time series from the page memory 12 to the semiconductor laser drive circuit 13 under the control of the control section 11. A semiconductor laser (not shown) emits light in accordance with a recording signal, and main scanning (in the axial direction of the photosensitive drum 1 ) is performed by the laser beam scanning system 14 and mirror 15 to irradiate the photosensitive layer 3 . Prior to irradiation, the photosensitive layer 3 is uniformly charged by the corona charger 4 to a surface potential of approximately aoov, and the potential of the portion irradiated with the laser beam decreases to approximately toov, resulting in an electrostatic pattern ( (not shown) is formed.

The electrostatic pattern is developed and visualized using toner from the developing device 5 having a polarity opposite to the charged potential. The toner image is electrostatically transferred to the cut sheet 17 of plain paper suspended from the cassette L6 by the action of an electric charge of opposite polarity to the toner applied from the corona charger 6 to the cut sheet 17. The transferred toner image is fixed on the cut sheet 17 by a heat roller 18. After the residual toner on the photosensitive layer on which the electrostatic pattern has been formed is removed by a cleaning blade 7, the entire surface is irradiated with light from a light source 8 to erase the electrostatic pattern and become ready for recording again.

(Problem to be solved by the invention) In order to obtain high-quality recording with this printer, the potential contrast of the electrostatic pattern from development to transfer must be sufficiently large, and the electrostatic pattern must be completely erased during full-surface light irradiation. It is necessary to For this purpose, a photoconductive material is required in which the surface potential of the photosensitive layer exhibits almost no dark attenuation and attenuation due to light irradiation occurs with high sensitivity. If the attenuation due to light irradiation is slow and the attenuation is fast in the dark, the electrostatic alpha contrast of the electrostatic pattern will be insufficient, resulting in low image density or background stains.If the attenuation due to light irradiation is slow, the electrostatic pattern will not be erased by full-surface light irradiation. It becomes incomplete and a ghost occurs. However, a photoconductive material that simultaneously satisfies the attenuation characteristics due to light irradiation and the attenuation characteristics in the dark, which are suitable for the electrophotographic recording process, has not yet been obtained. In general, if the attenuation due to light irradiation is highly sensitive, the attenuation in the dark will also be faster (higher sensitivity). Therefore, laser printers using electrophotographic recording processes use photoconductive materials with characteristics commensurate with the process speed, in other words, the moving speed of the photosensitive layer. In other words, in order to obtain high-quality records, it is necessary to record at a constant process speed, and when recording is performed by changing the moving speed of the recording medium depending on the received signal, as in facsimile, there is a problem that the recording quality is not constant. occurs.

To avoid this, in a facsimile receiving section using a laser printer for original documents, the recording signal for one page is temporarily stored in a page memory and recorded, as shown in FIG. In a facsimile, recording signals for one communication are continuously received, so a problem arises in that a page memory for two or more pages is required to receive data even during recording.

This means that for recording signals such as gradation signals that require several bits per pixel, the memory size becomes enormous, resulting in a large burden on the device cost.

The present invention has been made in view of the above-mentioned problems, and an object of the invention is to provide an electrostatic recording device with variable recording speed. Another object of the present invention is to provide an electrostatic recording device that maintains recording quality even when a recording medium is intermittently conveyed. Another object of the present invention is to provide an electrostatic recording apparatus that performs recording on plain paper with the same recording quality even if the recording speed changes by transporting the recording medium intermittently. Still another object is to provide an electrostatic recording device that can perform high-quality recording at high speed and while intermittently feeding a recording medium. Still another object is to provide an electrostatic recording device that can perform high-quality recording at high speed without being equipped with a page memory and while feeding the recording medium intermittently.

The present invention forms an electrostatic pattern on a solid dielectric recording medium that is conveyed at a variable moving speed or intermittently using a recording means that extracts ions from an ion generator as a recording signal, and the electrostatic pattern is visualized by a developing means. The purpose of this invention is to solve the above problems by using an electrographic recording device. Furthermore, a solid dielectric recording medium that is intermittently conveyed is uniformly charged by a precharging means, and an electrostatic pattern is formed by a recording means that extracts ions having a polarity opposite to the charging from an ion generator according to a recording signal. The above problem is solved using an electrostatic recording device. As an ion generator constituting these electrostatic recording devices, a first electrode is provided on one surface of a solid dielectric member, and an air gap region is provided at the joint of the solid dielectric member opposite to the first electrode on the other surface. An ion generator is provided with a second electrode so as to be present, and an electric potential is applied between the first electrode and the second electrode to cause a discharge in the air gap region. An ion generator having a first electrode on one side of a dielectric member and a second electrode on the other side opposite to the first electrode such that an air gap region exists at the joint of the solid dielectric member. and a bias power supply for forming a predetermined potential between the dielectric recording medium and the AC power supply for supplying an AC potential between the first electrode and the second electrode to generate a discharge in the air gap region. The present invention provides an electrostatic recording device in which the precharging means is a non-contact type non-magnetic one-component developing means as a developing means or a contact-type non-magnetic one-component developing means using an elastic roller as a developing roller. Furthermore, a precharging means for uniformly charging a solid dielectric recording medium that is intermittently conveyed, and a recording device for extracting ions of opposite polarity to the charging from an ion generator according to a recording signal to form an electrostatic pattern. The present invention provides an electrostatic recording device comprising a precharging means, a developing means, and a transfer means, and each of the precharging means, the recording means, and the transfer means includes an ion generating means for generating ions by destroying an air gap.

(Function) In the electrostatic recording device according to the present invention, the first electrode is provided on one side of the solid dielectric member, and an air gap region exists at the joint of the solid dielectric member opposite to the first electrode on the other side. By using an ion generator that is equipped with a second electrode and applies an alternating current potential between the first electrode and the second electrode to generate a discharge in the air gap region, ions can be generated at a high current density. Since the recording means can accumulate charges on the solid dielectric recording medium at high speed, a large electrostatic contrast of several 100 nanoseconds to several 10μSee can be obtained.

It can be obtained with Further, the time constant of the surface potential decay of the electrostatic pattern can be arbitrarily determined only from the resistance and dielectric constant of the solid dielectric recording medium, and a time constant of several tens of seconds or more can be obtained. In the precharging means included in the present invention, the solid dielectric recording medium is instantaneously and uniformly charged by ions at a high current density, and when a predetermined surface potential is reached, the transfer of ions is stopped. A predetermined surface potential can be obtained regardless of the residence time of the medium in the precharging means. A non-contact type non-magnetic single-component developing means, which is a developing means included in the electrostatic recording device of the present invention, in which development is performed while the toner and electrostatic pattern are separated from each other, or an insulating toner and an elastic roller is used as a developing roller. By using the non-contact type non-magnetic one-component developing means used, development is performed according to a predetermined surface potential regardless of the residence time of the electrostatic pattern in the developing means. In a transfer means including an ion generating device exhibiting the above-mentioned ion generating operation, a predetermined transfer potential can be obtained regardless of the residence time of the toner image in the transfer means. Therefore, in the electrostatic recording apparatus according to the present invention, a predetermined process is executed regardless of the residence time in each means.

(Example) Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 shows an embodiment of an electrostatic recording device according to the present invention.

The electrostatic recording device 20 has a dielectric layer 2 on a grounded conductor 21.
The recording medium drum 23 is surrounded by an ion recording head 24, a non-contact one-component non-magnetic developer 25, a toner transfer device 26, a cleaning blade 27, and a static eliminator 28. The recording signal modulated on the transmitting side enters the receiving section of the receiving facsimile machine via a transmission line, is demodulated by a demodulator 29, and is stored in a buffer memory 30. The ion storage head drive circuit 32 is driven in accordance with the stored storage signal under the control of the control unit 31, and by the recording operation described later, data is extracted from the ion recording head 24 onto the surface of the dielectric layer 22 passing through the ion recording head 24 according to the recording signal. A charge image is formed by the ions. The charge image is processed by a developing device 25 using a dry developer (hereinafter referred to as toner) having a polarity opposite to that of the charge image.
The image is developed and visualized. The toner image passing through the toner transfer device 2B is generated by the toner transfer device 26, and is transferred onto the recording paper 33 by electrostatic force formed by ions of opposite polarity to the toner image applied to the back surface of the recording paper 33. The toner image transferred to the recording paper 33 passes through a heat roller (not shown), which is a fixing device, and is fixed. Toner remaining on the dielectric layer 22 without being transferred to the recording paper 33 is removed by the cleaning blade 27.
will be removed.

When the surface of the dielectric layer 22 from which the toner has been removed passes through the remover 28, the charge on the surface is neutralized and the surface is reused.

The recording medium drum 23 is an aluminum drum with a specific resistance of 1O12 to 1014Ω/cm and a thickness of 100μm (
7) A film coated with polyvinylidene fluoride was used.

The configuration and recording operation of the ion recording head 24 will be explained using FIG. The ion recording head 24 consists of an ion generator 24-A and an accelerating electrode 24-B. The ion generator 24-A is 0. [On an alumina substrate 34 with a thickness of 135 o+m, gold is used as an electrode material and crystallized glass is used as a dielectric material, a solid dielectric material is formed in the pattern shown in FIG. 3 by a well-known thick film forming method, photolithography and etching. Five dielectric electrodes 35 as first electrodes and 20 ion generating electrodes 36 as second electrodes were formed with a certain 25 μm thick crystallized glass sandwiched therebetween. The dielectric electrode 35 (indicated by a broken line in FIG. 3, which will be described later) has a width of 160 μm and a thickness of 3 μm.

The thickness of the dielectric layer 37 is 25 μm. The width of the ion generating electrode 36 (indicated by a solid line in FIG. 3) is 180 μm.
5 has a thickness of 15 μm, and as shown in FIG. 3, five holes 38 each having a diameter of 100 μm are provided for each ion generating electrode at the intersections of the induction electrode 35 and the ion generating electrode 36 which intersect in a matrix shape. Two hundred holes 38 are arranged in the axial direction of the recording medium drum 23 at a pitch of 100 μm. The accelerating electrode 24-B has a thickness of 60 μm machined with a through hole of 200 μm in diameter in the same arrangement as the hole 38 shown in FIG.
A photosensitive polyimide was coated on the polyimide film 39 and a copper foil with a thickness of 18 μm so that the thickness after curing was 5 μm.
Copper/polyimide was etched in the same arrangement as the holes 38 shown in the figure, and a film provided with through holes of 100 μm in diameter was laminated so as to be concentric with the holes 38 provided in the ion generating electrode. 5 induction electrodes 35-1.35-2.3
5-3.35-4.35-5 are respectively induction electrode selection switches 41-1.41 whose other ends are connected to the AC electrode 40;
-2.41-3.41-4.41-5. The ion generating electrodes 3B-1, 36-2, 36-3 each have a signal voltage source 42 and an ion generating electrode selection switch 43-.
1.43-2.43-3.43-4.

Next, electrostatic pattern formation will be explained. Induction electrode 3
For example, as shown in FIG. 3, by selecting the switch 41 connected to the inductive electrode 41-2, an alternating current potential with a repeak voltage of 1000 V and a frequency of 20 KHz is applied from the power source 40 to the ion generating electrode 36 that intersects with the induction electrode 41-2. A high density current of positive and negative ions is generated within the 38. The ion generation mechanism of this type of ion generator is described in detail in Japanese Patent Laid-Open No. 54-53537, but will be briefly explained here. An AC positive potential is applied between the induction electrode 35 and the ion generation electrode 36 from the power source 40, and when the peripheral electric field Eh in the hole 38 exceeds the breakdown electric field of the air, air gap breakdown occurs in the region 37-r of the dielectric 37. occurs, forming positive ions within the hole 38. When the region 37-r is charged by the generated ions and its potential approaches that of the ion generating electrode 36, ion generation stops. Subsequently, when a negative potential is applied, negative ions are generated by the same mechanism as before. In this way, ion generation is not limited by previously generated ions, so ions with a high density current are generated. At the same time, by selecting the ion generating electrode selection switch 43, for example, the ion generating electrode 43-2 according to FIG.
300V is applied. Negative ions are extracted in the hole 38-a at the intersection of the selected image electrodes, and the extracted negative ions are applied to the dielectric layer 22 by the electric potential of -600V applied to the acceleration electrode 24-B and the conductor 21 by the electrode 44. attracted to the top. By matrix driving the induction electrode and the ion generating electrode, a surface potential according to the recording signal is generated on the dielectric layer 23 passing under the ion recording head 24 as described above.
A charge image of 500V is formed.

The charging time (surface potential formation) of the dielectric layer 22 by ions is several hundred nanoseconds to several 1O because the ionic current density is high.
μSee, which is extremely short, and when the accelerating electrode potential and the dielectric layer surface potential become the same, no more ions are attracted to the dielectric layer, so the dielectric layer surface potential is the accelerating electrode 24-B.
The potential applied to the conductor 21 will not exceed or exceed the potential applied to the conductor 21.
A given surface potential is obtained regardless of the transit time of the dielectric layer under the ion recording head.

The formed electrostatic pattern is sent to a non-contact one-component non-magnetic developer 25 by rotation of the recording medium drum 23.

The insulating toner of positive polarity supplied to the rotating developing sleeve 45 develops the electrostatic pattern of negative potential, and the electrostatic pattern is visualized. The toner on the developing sleeve 45 is separated from the guide layer 22.

Therefore, even if the developed toner image stops, the toner image will not be disturbed by the toner layer on the rotating developing sleeve 45, and the charge of the electrostatic pattern will not leak through the toner. .

An alternating current potential superimposed on a bias potential of -150 V is applied to the developing sleeve 45 as a developing potential.

The electrostatic pattern potential decreases as the toner develops, and the toner is attracted to the electrostatic pattern until it becomes approximately equal to the bias potential of the development potential. Even after the development has been saturated (when the potential difference has almost disappeared), the dielectric layer 22 is being fed intermittently, so even if the developed electrostatic pattern remains in the development area, the toner image will no longer be formed by the alternating current potential. Toner peels off.
Although the adhesion is repeated, an equilibrium state is reached and the toner concentration does not change.

That is, the toner density corresponding to the electrostatic pattern potential is maintained regardless of the residence time of the electrostatic pattern in the development area.

The toner image is transferred onto recording paper 33 by toner transfer device 26 . The function of the toner transfer device 26 will be explained using FIG. 4. The toner transfer device 26 has the same cross-sectional structure as the ion generator 24-A of the ion recording head 24, but has an ion generation electrode 4B and a hole 47 formed in the shape of a slit with a width of too μm.
A dielectric electrode 48 is provided in the axial direction of the dielectric drum 23 with a length exceeding the width of the recording paper 33. The manufacturing method is roughly the same as that of the ion generator 24-A except for the design, so the explanation will be omitted here. When an AC potential with a peak voltage tooov and a frequency of 25 KHz is applied from the electrode 49 to the induction electrode 48 and the ion generating electrode 46, positive and negative ions of high density current are generated in the hole 47. The explanation of the ion generation mechanism is omitted since it overlaps with the explanation in FIG. 2. The negative ions extracted by the action of the bias potential -eoov applied to the ion generating electrode 46 from the electrode 50 adhere to the back surface of the recording paper, and the positively charged toner is transferred to the recording paper 33 by the electrostatic field formed by the attached charges. will be stopped. Similar to the electrostatic pattern formation on the dielectric layer by the ion recording head, the surface potential of the back surface of the recording paper 33 (hereinafter referred to as transfer potential)
When the voltage approaches the bias potential applied to the ion generating electrode, the generated ions are no longer attracted to the recording paper 33.
Even if ion generation continues, the transfer potential saturates at a value close to the bias potential applied to the ion generation electrode.

If the recording paper 33 is plain paper, when the environmental temperature rises, ions that have absorbed moisture and adhered leak out, the transfer potential decreases, and density decreases and density unevenness occur due to poor transfer. Since this toner transfer device 26 generates a high-density current of ions, ions are supplied in the form of ions corresponding to the decrease in the transfer potential, and the transfer potential is restored. Even when the recording medium drum 23 and the recording paper 33 stop, the transfer potential does not rise any further and can always maintain a constant transfer potential. Toner remaining on the electrostatic pattern portion after toner transfer is removed by a cleaning blade 27. The electrostatic pattern is erased by a static eliminator 28.

The structure of the ion generator of the static eliminator 28 is the same as that of the ion transfer device described above, but the power source 50 is removed from the structure of the ion transfer device shown in FIG. The explanation of the ion generation mechanism is omitted since it overlaps with the explanation in FIG. 2. In the static eliminator 28, positive and negative ions are generated, and the positive ions are attracted by the potential of the electrostatic pattern and neutralize and erase the formed charge image. enables reuse.

Since positive and negative ions are generated in the static eliminator 28, the dielectric layer 22 is not charged even if it is stopped.

As is clear from the above description, the electrostatic recording device 20 can record on plain paper while rotating the recording medium drum 23 intermittently. Due to this feature, when this electrostatic recording device is used as a receiver output device of a facsimile, the capacity of the line buffer memory 30 that stores the recording signal demodulated by the demodulator 29 is sufficient for several lines, and the capacity for several pages is sufficient. It is possible to significantly reduce memory capacity compared to conventional devices that require additional instructions. Furthermore, since it is not necessary to record in page units, continuous paper can be used as the recording paper 33. In this case, a cutter may be provided if necessary.

Next, an electrostatic recording device which is another embodiment of the present invention will be described with reference to FIG. The electrostatic recording device 51 includes a recording medium drum 54 provided with a dielectric layer 53 on a grounded conductor 52.
Around the buri charger 55, ion recording head 56,
It consists of a contact type developer 57 using an insulating component non-magnetic toner that performs reversal development, a pressure roller 58, and a cleaning blade 59. Negative ions extracted from the ion recording head 56 in accordance with recording signals form a charge-neutralized image (static electrical pattern) is formed. The neutralized image is developed and visualized by a developing device 57 with toner having the same polarity as the charged charge. The toner image is pressed against the recording paper 60 by the pressure roller 58 and the recording medium drum 54, and is transferred to the recording paper BO and fixed at the same time. Toner remaining on the surface of the dielectric layer 53 without being transferred to the recording paper is removed by a cleaning blade 59.
Recording media drum 54 is reused.

As the recording medium drum 54, an aluminum drum whose surface was made of anodized aluminum impregnated with resin or the like was used.

The structure of the ion recording head 56 is schematically shown in FIG.

The ion recording head 5B consists of an ion generator 56-A and a control electrode 5B-B. Ion generator 5B-A is 0.63
After electrolytically plating the entire surface of the alumina substrate 61 with a thickness of 5+ am, a plate of 3 μm in thickness and 180 μm in width was formed using the pattern arrangement shown in FIG. 7 by photolithography and etching.
Five induction electrodes (indicated by hatching in FIG. 7) 82 were formed. Next 1 becomes the solid dielectric member 25
A 18 μm thick copper foil laminated on a μm polyimide film is subjected to photolithography and etching to form an ion generating electrode 63 and a shielding electrode 64 in the pattern arrangement shown in FIG. 7 (indicated by solid lines in FIG. 7). did. The ion generating electrode 63 and the shielding electrode 64 are connected to a common electrode 85 and grounded. The width of the shielding electrode 64 is 40 μm, and the distance between the shielding electrode 64 and the ion generating electrode B3 is 40 μm. The included angle with respect to the air gap region formed at the joint of the ion generating electrode 63 and the shielding electrode 64 with the polyimide film was processed to be 75 degrees. This sheet was laminated with a dielectric material B6 made of a polyimide film in between so that the induction electrode 62, ion generation electrode 63, and shielding electrode B4 had the positional relationship shown in FIG. 7, thereby constructing an ion generator 58-A. A feature of the ion generator 56-A is that a shielding electrode 64 is provided between the ion generating electrodes 63 so as to be at least partially included in a region facing the induction electrode 62, as shown in FIG. The shielding electrode 64 is provided to shield the electric field leaking between the ion generating electrodes 63 at an alternating current potential for ion generation, and effectively acts on the low voltage control of the ion current of this electrostatic recording apparatus. The control electrode 56-B was manufactured in the same manner as the acceleration electrode 24-B of the ion recording head shown in Figure 2, and was laminated with the ion generator 56-A to obtain the ion recording head 56. Electrostatic pattern formation in this electrostatic recording device will be explained using FIG. 8. Recording medium drum 54
The surface of the dielectric layer 53 is uniformly charged with positive charges by the bricharger 55. The structure of the bricharger 55 is the same as that of the transfer device shown in FIG. 4, and the ion generation mechanism is also the same, so a description thereof will be omitted. Dielectric electrode 67 and ion generating electrode 6
When an alternating current potential with a peak voltage of 1500 V and a frequency of 20 KIlz is applied from the voltage 1Fj69 during 8, positive and negative ions with a high current density are generated due to air gap destruction as described above. Positive ions are extracted by the +600v potential applied to the ion generating electrode from the power source 70, and the dielectric layer 5
3. Charge the surface to +600V. Even if the recording medium drum 54 stops rotating and the dielectric layer 53 remains under precharge, the charge on the recording paper in the transfer device shown in FIG. 4 is maintained at a constant potential even if the recording paper remains. Similarly, the precharge potential is kept approximately the same as the bias potential of the power supply 70. When the dielectric layer 63 charged in the same manner as - passes through the ion recording head 56, negative ions extracted from the ion recording head 56 according to the recording signal cause the dielectric layer 63 to
3 selectively neutralizes and eliminates positive ions on the surface to form a neutralized image 71. Induction electrode 62 of ion recording head 56
-L 62-2.62-3.62-4.62-5 is switch 72-1.72-2.72-3.72-4.72-
5 are sequentially switched and connected to the power source 73. The ion generating electrode 63 and the shielding electrode 64 are connected to a power source 73 and a power source 74 that applies a cutoff potential of ~40V. When applied from the power supply 73 to the selected induction electrode (induction electrode 72-1 is selected in FIG. 7 as an example), the ion generation electrode 63, and the shielding electrode 64, an AC potential with a peak voltage of 1500 V and a frequency of 20 KHz is applied. , selected induction electrode, ion generation electrode 63 and shielding electrode B
Positive and negative ions are generated in the hole 75 corresponding to the area where the two intersect. The control electrode 56-B has ~40
An ion current control potential of V (ON) or earth potential (OFF) is applied. When an earth potential is applied to the control electrode 56-B, a reverse electric field is generated that attracts negative ions toward the ion generation electrode, and the negative ions are attracted to the surface of the dielectric layer 53 by the surface potential of the dielectric layer 53. It will not be done. ~40V to control electrode 56-B
is applied, no force is generated to attract negative ions toward the ion-derived electrode, so negative ions are attracted to the dielectric layer 53.
is extracted from the ion recording head 5B and attracted to the surface of the dielectric layer 53 by the surface potential of the ion recording head 5B. The negative ions attracted to the surface of the dielectric layer 53 neutralize the positive ions on the surface of the dielectric layer 53, lowering the surface potential to 150 V or less, and forming a neutralized image 71. According to the electrostatic pattern forming method of this electrostatic recording device, the potential contrast of the electrostatic pattern can be selected almost by the precharge potential. A large potential contrast similar to the potential contrast can be obtained. Even if the recording medium drum 54 stops rotating after the electrostatic pattern is formed, an electric field that attracts negative ions toward the ion generating electrode acts between the control electrode 56-B, the ion generating electrode 63, and the shielding electrode 64. Therefore, an erroneous electrostatic pattern is not formed on the dielectric layer 53 in the non-recording portion. Positive ions are recorded in the ion recording head 5.
6, but since the surface potential of the formed electrostatic pattern is a positive potential or earth potential, it will not be attracted to the dielectric layer 53, and therefore the formed electrostatic pattern will not be disturbed. . When the shielding electrode 64 is present, extraction control of high-density negative ions into the dielectric layer 53 can be achieved with a control potential of several lOv as described above, but when there is no shielding electrode 64, the control potential of several toov is required. Is required. The function of the shield electrode 64 will be explained in detail.

In the case of the corona ion flow generator without the shielding electrode 64 shown in FIG. When each of the ion generation electrodes H8 of the generation source 115 is biased to +311V and an AC voltage with a peak-to-peak voltage of 1800 for ion generation is applied to the induction electrode 119, negative ions are generated from the ion generation electrode 118 and the recording medium 103 reach. The potential distribution at this time is as shown in FIG. 2(b).

However, as shown in FIG. 13(a), the shielding electrode 64
If the ion generating electrode is set at the same potential as the first
The potential distribution is shown in FIG. 3(b).

That is, when the shielding electrode 64 is present, the potential distribution between the ion source 15 and the control electrode 11B is less than several lOv, and it is possible to apply a reverse electric field to negative ions simply by setting the control electrode 116 to OV. This makes it possible to control negative ions. Furthermore, the ion generation electric field in the vicinity of the ion generation electrode is hardly affected, and stable ions are generated.

On the other hand, positive ions of opposite polarity generated by the AC voltage applied to the ion generating electrode 11g and the induction electrode 119 are
03 and the control electrode 116, the recording medium 1
03 and is absorbed by the control electrode 11B.

In this way, even if the shielding electrode 64 is provided, the amount of ions generated does not decrease. The reason is that the region where ions are generated is a strong electric field a few microns near the ion generating electrode.
This is because electric field fluctuations in this region hardly change because a 50 micron wide shielding electrode is provided in a 100 micron ion generation slit.

Next, the above-mentioned operating principle will be further explained theoretically. The basic operation is almost the same as that of a diode vacuum tube, but the difference is that a vacuum tube handles electrons, whereas the present invention handles ions.

Therefore, the relational expression between carrier velocity and voltage is different, resulting in a difference in the basic equation of ion current. Here, explanation will be given using basic equations and formulas for ionic current derived therefrom.

The basic equation showing the movement of ions is shown by the following equation.

V ■−μ d, , l−ρV ... (1) ■
is the potential at a point distance y from the ion source, ε
is the dielectric constant of air, ε. is the dielectric constant in vacuum, and ρ is the distance My
The charge f due to the ion flow that exists as a space charge in
f1TIV is the velocity at distance y, μ is the ion mobility, and i is the ion current at distance y.

The above equation shows a steady state in which space charges due to ions exist, and the ion generation electrode 11g and the dielectric electrode 11
The cycle of the AC voltage 123 for ion generation applied during 9 is the time for ions to reach the recording medium 103 (~2μSee
time), and the period of the signal voltage 124 applied to the control electrode 116 also needs to be sufficiently longer than this time.

By proactively creating and controlling space charges in this way, low-voltage drive is possible.In contrast to the conventional method, ion on/off control is performed by removing space charges. Multilevel recording is not possible and is fundamentally different.

Furthermore, an alternating current voltage (preferably a rectangular wave) is applied so that the applied signal voltage 124 and the generation of negative ions are synchronized,
It is preferable that an approximation to a low-temperature state is established.

When a voltage Vg is applied between the ion generation electrode 118 and the ion generation electrode 11B, the negative ions generated in this way are exposed to a surface potential V
s in the direction of the recording medium 103 as shown by the following equation, where a is the distance between the recording medium 103 and the control electrode IIB, and b is the distance between the control electrode 11G and the ion source 115.

k is a voltage amplification factor that takes into account the peripheral effect of the control electrode corresponding to the grid, as in the case of a diode vacuum tube. In other words,
If the ion through holes 118a on the control electrode 11B are approximated as existing periodically like the grid of a vacuum tube, the voltage amplification factor changes as a function of the distance from the electrode center due to the effect of the control electrode, and the voltage amplification factor changes as a function of the distance from the electrode center due to the effect of the control electrode. The value is the minimum.

The formula for the ion current above is, if the amount of ions generated is small,
The ionic current according to the above equation flows until it reaches the saturation current, but
Above the saturation current value, the current becomes constant. Therefore, when the amount of ions to be generated is less than the amount of ions to be generated, it does not depend on the amount of ions to be generated, but changes depending on the electrode structure, the voltage applied to the control electrode tte, and the surface potential of the recording medium 103.

From the above, by setting the ion generation AC voltage of each element of the ion recording head to a value higher than the ion generation amount necessary for recording, it is possible to suppress fluctuations in the ion generation amount caused by variations in the ion generation electrodes 11&. It becomes possible.

Further, the control voltage for shielding the ion flow is expressed by the following equation, and the voltage at which the upper width ratio is minimum at the center of the electrode is the maximum shielding voltage value.

By applying this voltage to the control type 1116 as a bias voltage, it becomes possible to cut off the ion current.

V--V/l (...(3) S Furthermore, it is preferable that the signal voltage applied to the control electrode tte has a value smaller than the bias voltage applied to the ion-generating electrode 118. This value is smaller than the voltage of the ion-derived electrode 118. is also large, some of the generated negative ions are transferred to the control a electrode 1.
1g, resulting in poor ion usage efficiency, and furthermore, the ion flow flowing toward the control electrode causes the recording medium 10
The potential between the control electrode 116 and the control electrode 116 fluctuates, further deteriorating the ion usage efficiency. Therefore, it is preferable to set the control electrode voltage according to the signal to a value below OV that maximizes the ion current. Therefore, it is preferable to use the shield electrode 64.

Electrostatic pattern 71 is developed by contact developer 57 using an insulating-component non-magnetic toner. The developing device 57 contacts the recording medium drum U with a developing sleeve 76, which is made of an elastic roller base coated with a thin layer of insulating non-magnetic toner using a blade (not shown) and coated with a flexible resistance layer. The dielectric layer 53 is rotated in the same direction at a speed faster than the moving speed of the dielectric layer 53 to perform development.

An example of such a developing device is Japanese Patent Laid-Open No. 62-336159. Developing bias voltage +200 is applied to developing sleeve 7B.
The electrostatic pattern is formed into a toner image by applying V and reversal development. This developing device has good reproducibility of fine lines because the developing sleeve, which serves as a developing electrode, is close to the electrostatic pattern. Even when the rotation of the recording medium drum 54 is stopped during development, the insulating toner is present between the developing sleeve and the electrostatic pattern, so leakage of electric charge from the non-image area is extremely small, and the leakage of the electric charge from the dielectric layer is extremely small. The decay time constant of the surface charge is long, so the potential contrast of the electrostatic pattern does not deteriorate.
A toner image that always provides the same optical density is obtained regardless of whether the recording medium drum 54 rotates or stops. When the toner image passes through a pressure roller 58 that is in contact with the recording medium drum 54 with a predetermined pressure, it is pressed against the recording paper 60.
Transfer and fixing occur simultaneously. Transcription. Fixing is performed only by pressure, and even if the rotation of the recording medium drum 54 is stopped and the pressure contact time becomes longer, the transfer and fixing of the toner image will not be adversely affected.

The recording paper is cut into a predetermined length using a cutter (not shown) as needed, and then discharged. The electrostatic pattern to which the toner image has been transferred is cleaned of remaining toner by a metal blade 59. In this electrostatic recording device, since the surface insulating layer of the recording medium drum 54 is very hard and smooth, toner cleaning efficiency is good and printing durability is excellent.

The dielectric layer 53 is again precharged and reused. The remaining portion of positive ions is replenished with enough ions to reach the bias potential of the recharger 55, and the neutralized portion is recharged to the bias potential of the recharger 55.

As is clear from the above description, this electrostatic recording device can always record with the same print quality even if the rotation of the recording medium drum changes or rotates intermittently.

Next, an electrostatic recording device according to an embodiment of the present invention will be described with reference to FIG. An electrostatic recording device 90 is the electrostatic recording device shown in FIG. 5, in which the pressure roller 58 for transferring toner is replaced with a roller transfer device 91, and a fixing device (not shown) is added.

Components in FIG. 9 that are the same as those in FIG. 5 are designated by the same numbers. The electrostatic recording device 90 uses a recording medium drum 54 having a dielectric layer 53 on a grounded conductor 52, a bricharger 55, an ion recording head 56, and an insulating component non-magnetic toner for reversal development. It consists of a contact type developing device 57, a roller transfer device 91, and a cleaning blade 59. Except for toner image transfer and fixing, the recording process, the electrostatic pattern forming process, the recording medium drum 54, the flash charger 55, the ion recording head 56, the contact type developer 57,
The cleaning blade 59 is the same as that shown in FIG. 5, so its explanation will be omitted. The structure and transfer operation of the roller transfer device 91 will be explained with reference to FIG. 10. The roller transfer device 91 consists of a transfer roller 92 and a power source 93 that supplies a transfer voltage. The transfer port 92 includes a flexible resistive layer 94, a conductive layer 95, a deformable 4Iiii layer 96, and a metal shaft 97. As the recording medium drum H rotates, the toner image 98 is conveyed to the toner transfer section (section B-C). At the toner transfer section,
The toner image 98 is pressed against the recording paper 60. The metal shaft 97 has a transfer voltage of minus 1, 5K, which has the opposite polarity to the toner.
V is supplied to the power supply 93, and the resistance layer 94 and the recording medium drum 5 are connected to each other.
The toner image 98 is transferred onto the recording paper 60 by the electrostatic force that acts between the toner images 98 and 4. In the toner transfer section, a transfer roller 92
Due to the elastic deformation of the elastic layer 96, the transfer pressure is also kept approximately constant. As such a transfer device, JP-A-63-104
There is No. 080. In this transfer device, toner is transferred by electrostatic force acting between the resistive layer 94 and the recording medium drum 54, so that it is not affected by the hygroscopicity of the recording paper. Even if the conveyance of the toner image stops at the toner transfer section (section B-C), the electrostatic force acting on the toner image does not change, and the flexible structure of the transfer roller prevents excessive pressure from being applied, so the toner is transferred to the dielectric layer. 53, and recording with constant image quality was obtained regardless of the passage time of the toner transfer portion of the dielectric layer.

It is clear from the above description that the electrostatic recording apparatus of the second and third embodiments can also be used as a facsimile receiver output device in the same way as the electrostatic recording apparatus of the first embodiment. It goes without saying that the present invention can also be used in recording apparatuses other than facsimile machines that perform variable recording speed or intermittently record.

[Effects of the Invention] With the electrostatic recording device of the present invention, high-quality recorded images can be obtained even if the recording speed changes during recording of one recording screen or even if recording is performed intermittently. In addition, it is possible to configure an electrostatic recording device that has a wide operating range with respect to environmental humidity and can obtain high-quality recorded images even if the recording speed changes while recording the recording screen or even if recording is performed intermittently. . By using the electrostatic recording device of the present invention in a facsimile receiving section, it is possible to construct a facsimile receiving section that can perform high-speed and intermittent recording on plain paper. In addition, the operating range is as wide as that of a thermal facsimile, it is capable of faster recording than a laser facsimile, and it can be used as a facsimile receiver that can perform intermittent recording. By using the electrostatic recording device of the present invention in a facsimile receiving section, it has become possible to significantly reduce memory capacity.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an electrostatic recording device according to a first embodiment of the present invention and the configuration of a facsimile receiving section using the electrostatic recording device as an output section, and FIG. A diagram for explaining the configuration of the recording head and the electrostatic pattern forming operation, FIG. 3 is a diagram showing the electrode configuration of the ion recording head shown in FIG. 2, and FIG. A diagram for explaining the function of the toner transfer device, FIG. 5 is a diagram showing the configuration of an electrostatic recording device according to a second embodiment of the present invention, and FIG. 6 is a diagram showing the structure of the electrostatic recording device of FIG. 7 is a diagram showing the configuration of the ion recording head shown in FIG. 6, and FIG. 8 is a diagram showing the electrode configuration of the ion recording head shown in FIG.
FIG. 9 is a diagram showing the configuration of the electrostatic recording device which is a third embodiment according to the present invention, and FIG. FIG. 11 is a diagram for explaining the configuration and operation of the roller transfer device of the electrostatic recording device shown in FIG. Figures 1 to 13 are diagrams for explaining the action of the shielding electrode. 1O129...Demodulator 12.30...Memory 22.53...Dielectric layer 23.54...Recording medium drum 24.56...Ion: 2 Recording head 24-B...Accelerating electrode 25 .57...Developer 26.58.91...Transfer device 27.59...Cleaning blade 28...Static eliminator 35.48.62.67...Induction electrode 36.46.6
3.68...Ion generation electrode 56-B...Control electrode

Claims (1)

[Scope of Claims] (1) In an electrostatic recording device in which an electrostatic pattern is formed on a solid dielectric recording medium according to a recording signal by a recording means and visualized by a developing means, ions are extracted by an ion generator according to the recording signal. 1. An electrostatic recording device characterized in that an electrostatic pattern is formed on a solid dielectric recording medium whose moving speed is variable using recording means. (2) In an electrostatic recording device in which an electrostatic pattern is formed on a solid dielectric recording medium according to a recording signal by a recording means and visualized by a developing means, an electrostatic pattern is formed intermittently by a recording means that extracts ions from an ion generator according to a recording signal. 1. An electrostatic recording device that forms an electrostatic pattern on a solid dielectric recording medium that is conveyed. (3) The ion generator has a first electrode on one side of the solid dielectric member, and a second electrode on the other side opposite to the first electrode so that an air gap region exists at the joint of the solid dielectric member. 3. The ion generator according to claim 1, wherein the ion generator is provided with an electrode, and an alternating current potential is applied between the first electrode and the second electrode to generate a discharge in the air gap region. electrostatic recording device. (4) The developing means is a non-contact type non-magnetic one-component developing means or a contact-type non-magnetic one-component developing means using an elastic roller having an insulating toner and a resistance layer on the surface as a developing roller. The electrostatic recording device according to claim 1 or 2. (5) The recording means has a first electrode on one side of the solid dielectric member, and a second electrode on the other side of the solid dielectric member so that an air gap region exists at the joint of the solid dielectric member. providing an electrode, applying an alternating current potential between the first electrode and the second electrode;
Claim comprising: an ion generator configured to generate a discharge in an air gap region; and means for extracting ions having a polarity opposite to the charging potential from the ion generator in accordance with a recording signal at a potential lower than the charging potential. 1 or 2
The electrostatic recording device described. (6) In an electrostatic recording device in which an electrostatic pattern is formed on a solid dielectric recording medium according to a recording signal by a recording means and visualized by a developing means, the solid dielectric recording medium that is intermittently conveyed by a puy charge means is uniformly An electrostatic recording device, characterized in that an electrostatic pattern is formed by a recording means that charges an ion and extracts ions of opposite charged polarity from an ion generator according to a recording signal. (7) The precharging means has a first electrode on one side of the solid dielectric member and a second electrode on the other side opposite to the first electrode so that an air gap region exists at the joint of the solid dielectric member. A predetermined potential is applied between an ion generator provided with an electrode, an AC power source that supplies an AC potential between a first electrode and a second electrode, and a dielectric recording medium to generate a discharge in an air gap region. 7. The electrostatic recording device according to claim 6, further comprising a bias power source for forming the electrostatic recording device. (8) The ion generator has a first electrode on one side of the solid dielectric member and a second electrode on the other side opposite to the first electrode so that an air gap region exists at the joint of the solid dielectric member. Claim 7, characterized in that the ion generator includes an ion generator provided with an electrode, and an AC power source that supplies an AC potential between the first electrode and the second electrode to generate a discharge in the air gap region.
The electrostatic recording device described. (9) The developing means is a non-contact type non-magnetic one-component developing means or a contact-type non-magnetic one-component developing means using an elastic roller having an insulating toner and a resistance layer on the surface as a developing roller. Claim 6
Or the electrostatic recording device according to 10. (10) In an electrostatic recording device in which an electrostatic pattern is formed on a solid dielectric recording medium according to a recording signal by a recording means, visualized by a developing means, and the visible image is transferred to the recording medium by a transfer means, the electrostatic pattern is intermittently conveyed. a precharging means for uniformly charging a solid dielectric recording medium, a recording means for extracting ions having a polarity opposite to the charging from an ion generator according to a recording signal to form an electrostatic pattern, and a developing means. . An electrostatic recording apparatus, comprising a transfer means, and each of the precharge means, the recording means, and the transfer means includes ion generation means for generating ions by destroying an air gap.