JPS60199668A - Picture recorder - Google Patents

Abstract

PURPOSE:To make the writing and erasure of a portion of picture possible, by arranging the recording electrodes assembly prepared by laminating the first electrode and the second electrode with an insulation layer being interposed thereween, adjacent to the back surface of a recording medium. CONSTITUTION:Respective gaps between the first electrode 8 and the second electrode 9, and between the second electrode 9 and the third electrode 10 are insulated with dielectrics 11 and 12, and the second electrode 9, the dielectric 12 and the third electrode 10 are perforated with an open hole 13. The recording electrodes assembly 2 composed of their assembly faces to each other in adjacency of a recording medium 1. When alternating voltage is applied between the first electrode 8 and the second electrode 9, corona discharge is generated between the dielectric 11 and the second electrode 9 and positive ion and negative ion are generated in the open hole 13. Thereby, when it is designed that the picture recording in the case of moving the recording medium 1 in the arrowed mark A direction while the picture erasure in the case of moving it inversely to the A direction are carried out, the freely writing and erasure of toner picture on the recording medium are enabled.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image recording apparatus, and particularly to an image recording apparatus that records an image by directly attaching magnetic and conductive toner to a recording medium in response to an image signal.

Conventional image recording apparatuses of this type employ a method generally known as a contrast method.

This uses an insulating film with high electrical resistance as a recording medium, moves the insulating film, places a recording electrode close to the back of the film, and contacts conductive magnetic toner carried on a developing member on the top and bottom surfaces. Then, a recording signal voltage corresponding to the image pattern is applied to the recording electrode to cause toner to adhere to the recording medium and visualize it.

An outline of a conventional example of such an image recording apparatus will be explained with reference to FIG. In Fig. 1, reference numeral 1 denotes a recording medium such as an insulating film, and on the back side, a recording electrode 2 consisting of a number of needle electrodes arranged insulated from each other is placed close to and facing each other. A signal voltage corresponding to the image pattern is applied independently to the signal generator 3. A developing device 4 is disposed on the opposite side of the recording medium 1, that is, on the surface side facing the recording electrode 2, and the developing device 4 has a sleeve 5 made of a hollow cylinder made of a non-magnetic conductive material. Inside it there is a fixed and stationary magnet 6. The sleeve 5 contains conductive toner T (preferably magnetic) housed in the toner hopper 7.
immersed in

The recording medium 1 moves in the direction of arrow A, and the character signal generator 3 applies a recording voltage to the recording electrode 2 according to the multi-image pattern.

As the sleeve 5 rotates in the direction of arrow B, the toner T is transferred to the magnet 6.
When the toner T is transported over the system sleeve 5 and comes into contact with the recording medium 1 due to the zero action, this toner T becomes the opposite electrode of the recording electrode 2, and a discharge occurs between the tip of the recording electrode 2 to which the recording voltage is applied and the recording medium 1. At the same time that an electric charge is generated on the recording medium 1, an electric charge of the opposite polarity to the electric charge is injected from the sleeve 5 through the entire toner T, and due to the electrostatic attraction of these electric charges, the electric charge is generated on the recording medium 1. The toner T adheres and a visible image is obtained.

The disadvantage of this device is that the distance between the recording electrode 2 and the recording medium 1 is several μm.
This means that the gaps must be made as small as several tens of micrometers, and it is difficult to create uniform gaps over a wide mesobody.

In order to solve this problem, there is a method to make the surface of the recording medium 1 rough as described in Japanese Patent Application Laid-open No. 57-105758, but if this is done, the recording medium 1 is transparent and it is unsightly when viewed directly. Otherwise, when the recording medium 1 is used repeatedly, the operation becomes unstable due to wear and the like.

Furthermore, in order to perform divided driving in the apparatus shown in FIG. 1, divided counter electrodes are provided on the sleeve surface as shown in Japanese Patent Laid-Open No. 57-185453, and a voltage is applied to the group of counter electrodes in response to an image signal. Although this is possible by applying voltage, there are drawbacks such as alignment of the divided counter electrode and recording electrode and the need for a special power source. (Divided driving divides the recording electrodes into blocks, connects the recording electrode groups in parallel, divides the electrodes (sleeve surface) facing the recording electrode group, and applies voltage between the electrodes.) The present invention It is an object of the present invention to provide an image recording device which eliminates the drawbacks of the above-mentioned conventional example and at the same time makes it possible to partially erase and write an image.

An image recording apparatus according to a first aspect of the present invention includes a toner carrier that conveys conductive toner and brings it into contact with one surface of a recording medium such as a moving dielectric film; I→, and the 111th !
It is penetrated by a large number of openings distributed in the width direction that open toward the recording medium except for the electrode and the insulating layer, and at least the second electrode forms an electrode group whose number corresponds to the number of the openings, It is characterized by having means for applying an alternating current voltage between the first electrode and the second electrode, and means for applying an image signal voltage between the second electrode and the toner carrier.

An image recording apparatus according to a second aspect of the present invention includes a toner carrier that conveys and brings conductive toner into contact with one surface of a recording medium made of a moving dielectric film; The recording electrode assembly is provided with a recording electrode assembly disposed close to each other in the width direction of the recording electrode assembly on the other side, and the recording electrode assembly is distributed in the width direction opening toward the recording medium except for the side far from the recording medium and the first insulating layer. It is penetrated by many holes,
At least the second electrode forms a number of electrode groups corresponding to the number of openings, an alternating current voltage is applied between the first electrode and the second electrode, and an alternating current voltage is applied between the second electrode and the toner carrier. The second invention is characterized in that the image signal voltage is provided with means for applying a DC voltage or an AC voltage having a phase opposite to the AC voltage between the third electrode and the toner carrier. The basic configuration of the embodiment is shown.

The same numbers as in FIG. 1 represent parts having the same configuration and function. 8 is a first electrode, 9 is a second electrode, 1° is a third electrode, and between each electrode is a first dielectric 11 and a second dielectric.
a dielectric 12 insulated, and a second electrode 9;
The second dielectric 12 and the third electrode 10 are penetrated by an opening 13 . These combinations are recorded as a whole using electrode assembly 2.
shall be. The recording electrode assembly 2 closely faces the recording medium 1 and extends over its entire width. A large number of openings 13 are arranged and distributed in the width direction of the recording medium 1.
The electrodes 9 form a group of independent electrodes as many as the number of apertures 1β, and are adapted to receive individual signal voltages corresponding to the image from the character signal generator 3. When an AC voltage is applied between the first electrode 8 and the second electrode 9, corona discharge occurs between the first dielectric 11 and the second electrode 9, and positive ions,
Negative ions are generated.

At this time, the M2 electrode 9,
If a potential gradient is applied between the third electrode 10 and the sleeve 5, ions will adhere to the recording medium 1. The principles of these ion generation and movement processes are detailed in Japanese Patent Application Laid-Open No. 54-78134.

At the same time, these charged particles (ions) attached to the recording medium 1
Charges of opposite polarity are induced in the toner T through the sleeve 5, and the toner adheres to the recording medium 1 due to their electrostatic attraction, forming a visualized toner image. This point is the first
This is the same as explained in the figure.

In order to later remove the attached toner T (that is, erase the image), the charge on the recording medium 1 may be eliminated.

For this purpose, the second electrode 9, the third electrode 10, and the sleeve 5 are made to have the same potential. Then, among the positive ions and negative ions in the apertures 13, ions with a polarity opposite to the polarity of the charge on the recording medium 1 are attracted to the recording medium 1, the previous charge on the recording medium 1 is eliminated, and the toner is removed. The charge on T also returns to the sleeve, and the adhesion between the recording medium 1 and the toner T disappears, and the toner T is attracted to the magnet 6 and collected by the toner carrier or -7.

In the configuration described above, if the image is recorded when the recording medium 1 is moved in the direction of the arrow A, and the busy image is erased when the recording medium 1 is moved in the opposite direction to the arrow A, the toner image can be freely recorded on the recording medium. It becomes possible to write and erase. To erase the image, instead of moving the recording medium in the opposite direction to that during image formation, the recording medium may be made into an endless belt and the image may be erased when the recording medium is rotated once in the same direction as during image formation. .

Hereinafter, a specific explanation of this embodiment will be given.

As the recording medium l, a dielectric film such as polyester, polyethylene, polyvinyl chloride, etc.
- A film having a resistance value of 2 or more and high tensile strength is desirable. The thickness may be 1 μm to 500 μm, but it is desirable to make it thinner to increase the resolution, and thicker to increase the tensile strength.

In this example, a 25 μm thick polyester film was used.

The thickness of the first dielectric 11 is related to the output voltage of the AC power supply 14, and the thinner the first dielectric 11, the lower the applied voltage.
Mica with a thickness of 0 μm was used. Moreover, the first electrode 8. The second electrode 9 and the third electrode 10 are each made of 20μ thick stainless steel foil. As the second dielectric 12, the opening 13
In this example, ceramic with a thickness of 100 μm is used, but other insulators such as mica, glass, or polymeric resin such as polyimide may also be used), and the diameter of the opening 13 is 130 μm. The aperture 13 is usually formed on the recording medium 1
The second electrodes 9 are arranged in a line perpendicular to the movement direction of the second electrodes 9.
An electrode array is formed so that the voltage can be independently controlled by the number of openings 13.

However, when increasing the recording density, the apertures 13 are arranged staggered or diagonally in several rows, and the first electrode 8 and second electrode 9
It is also possible to form a matrix array shape as shown in FIG. 3 in combination with the above. That is, in FIGS. 3(a) and 3(b), 10 is a finger-shaped third electrode, 1'1 is a first electric wire, 12 is a second dielectric, and 13 is an opening. The first electrode 8 intersects with the selector pars 8-1, 8-2.・
..., in the shape of an 8-4. The second electrode 9 and the second dielectric 12 have a finger-like shape similar to the third electrode 10.

Alternatively, the second dielectric and the third electrode 1o may each be made of a single plate with a slit (elongated hole), but the third electrode is usually made of a single plate with a hole 13. A plate-shaped piece is often used.

When the first electrode 8 is divided into a houndstooth pattern or a shape as shown in FIG. 3, it is desirable to cover them with an insulator to improve insulation. In this case, as shown in Fig. 3, the first electrode 8-1.8-2
．． An alternating current voltage is finally applied to 8-3 and 8-4 to form an intersection where the signal voltage is applied to the signal electrodes, thereby performing divided driving.

The distance between the third electrode 10 and the recording medium 1 was set to 0.2 mm.

As the sleeve 5 facing the recording electrode assembly 2, a stainless steel cylinder with a diameter of 22 m is used, and the internal magnet 6 has four poles evenly magnetized to create a magnetic flux density of 46 on the surface of the sleeve 50.
One that yielded 0 Gauss was used. Sleeve 5 is indicated by arrow B
direction at 64 revolutions per minute by a drive source (not shown).

The gap between the recording medium 1 and the sleeve 5 is 0. ! 5m+, and a non-magnetic doctor blade 15 is attached to the toner hopper 7 in order to form a uniform radius of toner on the sleeve 5.

The toner T may be any magnetic toner having a resistance value of 10Ω-α or less, but in this example, 355 Image Nong Powder manufactured by 3M Company was used.

With the above configuration, the recording medium 1 is moved in the direction of the arrow at 180 mm per second, the frequency is 500 k)lz, the voltage is 2,
An AC voltage of 5 kV vP-T (peak-to-peak voltage) is applied between the first electrode 8 and the second electrode 9 from the AC power supply 14, and the character signal generator 3 applies the AC voltage to the second electrode 9. , -700V image signal if image signal is present, -40V if not
A voltage of 0v is applied. However, 1700V is applied to the second electrode 9 for the area where an image is to be recorded, and 1400V is applied to the second electrode 9 for other areas. This voltage is a value based on sleeve 5 (ground). Third
A DC power supply 16'p-400V is constantly applied to the electrode 1o.

In this state, when a recording signal voltage corresponding to the image pattern is applied to the character signal generator 3 as described above, negative ions adhere to the recording medium 1. At this time, a glass charge is injected into the toner T on the opposite side from the surface of the sleeve 5, and the negative ions attached to the recording medium 1 and the toner T are injected into the toner T on the opposite side.
are attracted to each other, and the toner T adheres to the recording medium 1. When there is no recording signal, the second electrode 9 is maintained at -400V, and the second electrode 9 inside the aperture 13 and the third electrode 1o create a reverse electric field that does not allow ions to pass through, so ions do not enter the recording medium 1. Since - does not adhere, toner T does not adhere. By continuously performing the above operations, a visible image made of toner appears on the recording medium 1.

On the other hand, when removing the toner T attached to the recording medium 1, the recording medium 1 is moved in the opposite direction, and an AC power source is connected between the first electrode 8 and the second electrode 9.
By applying an alternating current voltage to 4 and grounding the second electrode 9, the third electrode 10, and the sleeve 5, the first electrode 8 and the second
Of the ions obtained by alternating current corona discharge with the electrode 9, ions of opposite polarity are attracted to the recording medium 1 by the charges already attached to the recording medium 1.

In this embodiment, since negative charges are attached to the recording medium 1 as described above, the glass ions are attracted, and these cancel each other out, so that the charges on the recording medium 1 disappear. At the same time, the charge injected into the toner T is transferred to the sleeve 5.
Since the toner T flows into the toner T, there is no adhesive force between the recording medium 1 and the toner T. This toner T is collected by the magnetic force generated by the magnet 6 into the toner hole/4-7 and is reused n1.

Furthermore, in the above explanation, the second electrode 9 and the third electrode 10 are grounded, but the second electrode 9 may be supplied with an AC voltage of the same phase as the AC power supply 14. It is preferable to set the output voltage of the switch slightly higher.

The visible image obtained on the recording medium 1 may be transferred to another recording paper using pressure transfer, heat transfer, corona transfer, etc. (not shown), or this recording medium 1 may be If it is transparent, the toner can be fixed on it by heating, or it can be irradiated with illumination light without being fixed.
Of course, it is also possible to use it as a projection display as it is in a form that functions as an original film for an overhead flow projector, or it can also be used as a display that can be viewed directly without projection.

FIG. 4 is a schematic cross-sectional view of an image recording apparatus based on the first aspect of the present invention. The symbols in the figure correspond to those in FIG. 3. In FIG. 4, the basic operation is the same as in FIGS. 2 and 3, but the third electrode IO is not provided. An AC voltage is applied between the first electrode 8 and the second electrode 9, and an image signal voltage is applied between the second electrode 9 and the sleeve 5. Figure 2 also shows the case of erasure.

It is sufficient to follow the method shown in Fig. 3. Compared to the configuration shown in FIG. 4, the configurations shown in FIGS. 2 and 3 have advantages such as being able to obtain an electric field that accelerates ions, preventing the ions generated in the aperture 13 from spreading, and improving the recording resolution. be.

As explained above, according to the present invention, by bringing the recording electrode needle and the recording medium close to each other with a small gap, a good image can be obtained without the need to roughen the recording medium, and at the same time, it is possible to partially erase and erase images.
Writing is also possible. Not only is it possible to widen the gap between the recording electrode assembly and the recording medium, which makes the design easier, but also because there is no contact between the recording medium and the recording electrode assembly, the life of the recording medium is significantly extended. becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a sectional view illustrating an example of an image recording device using a conventional contrast graphing method, FIG. 2 is a schematic sectional view illustrating an embodiment of an image recording device according to a second aspect of the present invention, and FIG. 3(a)
*(b) is a diagram of a detailed example of the electrode in FIG. 2, and FIG. 4 is a schematic diagram showing the first aspect of the present invention. 1... Recording medium 2... Recording electrode (assembly) 3...
・Character signal generator 5...Sleeve 6...Magnet 8
...First electrode 9...Second electrode 10...Third electrode 11...First
Dielectric 12... Second dielectric 13... Opening 14.
...AC power supply 16...DC power supply T...Toner Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. A toner carrier that conveys and contacts conductive toner on one side of a recording medium such as a moving dielectric film, and a toner carrier on the other side of the recording medium opposite to the toner carrier. and a recording electrode assembly arranged close to each other in the width direction, and the recording electrode assembly is penetrated by a large number of openings distributed in the width direction that open from the recording medium to the recording medium except for the insulating layer. At least the second electrode forms a number of electrode groups corresponding to the number of openings, and an AC voltage is applied between the first electrode and the second electrode, and an AC voltage is applied between the second electrode and the toner carrier. An image recording device characterized in that the device comprises means for applying an image signal voltage. 2. A toner carrier that conveys and brings conductive toner into contact with one surface of a recording medium such as a moving dielectric film, and a toner carrier that faces the toner carrier and extends across the width of the other surface of the recording medium. and a recording electrode assembly disposed in close proximity to each other, the recording electrode assembly being pierced by a number of openings distributed in the width direction that open toward the recording medium and the recording medium except for the first electrode and the first insulating layer. At least the second electrode forms a number of electrode groups corresponding to the number of the apertures, an AC voltage is applied between the first electrode and the second electrode, and an AC voltage is applied between the second electrode and the toner carrier. An image recording apparatus characterized by comprising means for applying an image signal voltage between the third electrode and the toner carrier, and a means for applying a DC voltage or an AC voltage having a phase opposite to the AC voltage between the third electrode and the toner carrier.