JPH06262760A - Recorder - Google Patents

Abstract

PURPOSE:To provide an electrostatic accelerating type ink jet recorder which is little influenced from a kind of an ink solution and variation in physical properties, and can record highly precisely by a method wherein discharge of the ink is enabled to be easily controlled without necessitating a high voltage pulse generation circuit requiring a high costed high tension proof IC. CONSTITUTION:A recording medium 2 bearing an electrostatic latent image, and an ink solution discharge part 1 which is provided, in a non-contact state, opposed to the recording medium 2, and has an ink holding part 13, at least one counter electrodes 15 provided so as to be immersed in the ink solution in the solution holding part, and an opening part 18 for discharging the ink solution are equipped to a recorder. The ink solution is discharged from the opening part 18 by an electric field between the electrostatic latent image on the recording medium and the counter electrode 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium carrying an electrostatic latent image, an ink liquid holding portion, an ink liquid holding portion, and an ink liquid in the ink liquid holding portion. The present invention relates to an electrostatic acceleration type ink jet recording apparatus including at least one counter electrode provided so as to be buried in a substrate, and an ink liquid ejecting section having an opening for ejecting ink liquid.

[0002]

2. Description of the Related Art A so-called ink jet recording method has been conventionally known in which liquid ink is ejected onto a recording medium to form recording dots.

This ink jet recording method has the advantages that it is less noisy than other recording methods and does not require processing such as development and fixing, and is drawing attention as a plain paper recording technique.

To date, many ink jet recording methods have been devised and disclosed. In particular, an ink jet recording method called a slit jet recording method in which ink ejection openings are formed in a slit shape is provided in the longitudinal direction of the slit ink ejection openings. It has attracted attention because of its advantages such as a large number of recording electrodes for controlling ink ejection, high-speed recording being possible, and ink clogging being less likely to occur.

The electrostatic acceleration type ink jet recording apparatus according to this slit jet recording method is arranged at a rate of about 8 lines / mm in the slit longitudinal direction in a slit-shaped ink ejection port having a width of about 100 μm and a length of about 200 mm. It is provided with a large number of recording electrodes and means for applying a high voltage pulse corresponding to recording information between the recording electrodes selected from the recording electrode group. Then, the ink in the vicinity of the recording electrode, to which the high voltage is selectively applied, is attracted to the back electrode by electrostatic force and adheres to the recording body arranged between the ink ejection port and the back electrode, corresponding to the recording information. The ink image points are formed on the recording medium.

As a method for selectively applying a high voltage pulse to a large number of recording electrodes, a large number of recording electrodes are connected to respective high voltage pulse generating circuits, and the high voltage pulse generating circuit is selected according to recording information. Method is used. However, this method requires a number of high-voltage pulse generation circuits as many as the recording electrodes, which makes the device itself large and expensive, which is not practical.

In recent years, each of the recording electrodes is commonly connected to the first high-voltage applying electrode via the photoconductive insulator, and each of the recording electrodes is connected to the second high-voltage applying electrode via a fixed resistor. A method has been proposed in which a recording electrode potential is changed corresponding to recording information by irradiating the photoconductive insulator with an optical signal corresponding to recording information while applying a DC high voltage in between. (Kaisho 60-250962). But,
The method of changing the recording electrode potential by irradiating the photoconductive insulator with an optical signal utilizes the property that the electric resistance changes in accordance with the amount of light received by the photoconductive insulator. . However, this method has a limit to the withstand voltage of the photoconductive insulator and the fixed resistor interposed between the recording electrode and the high-voltage applying electrode, and it is not possible to increase the potential change width of the recording electrode. Discharge control was difficult.

In addition to the above-mentioned problems, the method of selectively applying a high voltage pulse to a large number of these recording electrodes has a problem of electric field interference between adjacent recording electrodes.
/ 1, Vol. J66-C, No. 1, p48). In order to avoid this interference, it is not possible to apply a voltage to adjacent recording electrodes at the same time, and it is necessary to carry out a division drive in which high voltage pulses are applied to the recording electrodes every other pulse. For this reason, the printing speed must be reduced. Also,
In order to prevent current leakage through the ink liquid between the recording electrodes, it is necessary to use a petroleum-based ink liquid having a high electric resistance.
Further, there is a drawback in that the discharge characteristic of the ink liquid is largely changed due to the change of the physical properties of the ink liquid due to the current leakage, especially the change of the electric resistance due to the temperature change. Further, the current leakage between the recording electrodes becomes more severe as the distance between the recording electrodes becomes shorter. Therefore, the number of recording electrodes per unit length should be increased in order to achieve high-definition recording, that is, the electrode density should be increased. Is difficult. Therefore, there is a limit to high-definition recording in slit jet recording.

[0009]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and does not require a high-voltage pulse generation circuit that requires an expensive high-voltage IC, and facilitates ink ejection control. Therefore, it is an object of the present invention to provide an electrostatic acceleration type inkjet recording apparatus which is less affected by changes in the type and physical properties of ink liquid and which enables high-definition recording.

[0010]

According to the present invention, there is provided a recording medium carrying an electrostatic latent image, and an ink liquid holding section, which is provided in a non-contact state so as to face the recording medium. At least one counter electrode provided so as to be buried in the ink liquid, and an ink liquid ejecting portion having an opening for ejecting the ink liquid are provided, and the electrostatic latent image on the recording medium is opposed to the electrostatic latent image. An ink liquid is ejected from the opening by an electric field between the electrode and the recording device.

In the ink jet recording apparatus of the present invention, it is the electrostatic latent image on the recording medium that determines the ON / OFF state of ink ejection. Therefore, high voltage pulses are individually applied to the counter electrodes in the ink liquid. It is not necessary to apply the pulse voltage, and it is possible to apply the pulse voltage to all the counter electrodes at the same time. Therefore, an individual high voltage pulse generation circuit or the like becomes unnecessary, and high definition recording is realized. In addition, there is no difficulty in controlling ink ejection as in the case of a device using a conventional photoconductive insulator.

In the present invention, the recording medium on which the ink droplets are finally recorded is provided between the recording medium and the ink ejecting portion (on the recording medium) to directly perform the recording by the ink droplets. It is also possible to perform indirect recording in which an image is formed by ink droplets on the upper surface and then transferred from the recording medium to the recording medium.

As the ink ejecting section in the ink jet recording apparatus of the present invention, any of those conventionally used in the electrostatic acceleration type can be applied. That is, not only the simplest single-nozzle type inkjet nozzle can be applied, but also an inkjet nozzle for slit jet having a plurality of electrodes on the inner wall can be used without adding a pulse generating circuit to each electrode.

In a further advanced embodiment of the present invention, a recording medium carrying an electrostatic latent image, which comprises a back electrode and a layer made of a pyroelectric material provided thereon, is used. An electrostatic latent image is formed on the pyroelectric layer by heating the recording medium, and a DC or AC bias voltage is applied to the back electrode to record information.

The potential of the electrostatic latent image on the recording medium must be high in order to stabilize the ejection of ink, but it is easy to heat the recording medium by using a pyroelectric material as the recording medium. It is possible to obtain an electric potential of about several 100V to 2000V. Therefore, it is not necessary to use a high voltage source for forming the electrostatic latent image.

As a recording medium, a dielectric layer may be provided between the pyroelectric layer and the back electrode to raise the apparent potential with respect to the back electrode. It is also possible to form a floating electrode layer on the pyroelectric layer, which is made of a dielectric material and metal fine particles and is insulated from each other.

Examples of such a pyroelectric material are polyvinylidene fluoride, copolymers of vinylidene fluoride and ethylene trifluoride, copolymers of vinylidene fluoride and ethylene tetrafluoride,
Pyroelectric resin material such as a copolymer of vinylidene cyanide and another monomer, or PZT (Pb ₂ ZrO ₃ ,
PbTi0 ₃ ) ceramics, PLZT (Pb ₂ Zr
O ₃ , PbTiO ₃ , La ₂ O ₃ ) pyroelectric ceramics such as BaTiO ₃ , LiTaO ₃ , LiN
Inorganic pyroelectric crystal materials such as bO ₃ and quartz, and organic pyroelectric crystal materials such as Rochelle salt and triglycine sulphate powdered into a resin selected from the group consisting of thermoplastic resins or thermosetting resins Materials dispersed in can be used. The pyroelectric body formed of these materials is used as a recording medium by forming it into an electret by a polarization operation such as poling, or by aligning the directions of spontaneous polarization.

In still another embodiment of the present invention, as a recording medium carrying an electrostatic latent image, a recording medium composed of a back electrode and a layer made of a photoconductor provided thereon is used, and the recording is carried out. By irradiating the medium with light, an electrostatic latent image is formed on the photoconductor, and DC and AC bias voltages are applied to the back electrode to record information.

By using a photoconductive insulator as a recording medium, it is possible to apply all of the known electrophotographic method for forming an electrostatic latent image on a photoconductor and its parts and materials. .

It is also effective to prevent the surface of the photoconductor from becoming dirty by using a photoconductor having a transparent insulating layer on a photoconductive layer as a recording medium.

[0021]

The recording method in the conventional electrostatic acceleration type ink jet recording apparatus is the on-demand type in which the pulse voltage is applied to the electrode in the ink ejection portion only during recording, or the periodic voltage is applied to the electrode in the ink ejection portion. To continuously eject ink droplets, and deflect the flight direction of the ink droplets by a deflection electrode to determine whether to record on the recording medium or drop it in the gutter and collect it in the ink tank. Broadly divided.

On the other hand, in the ink jet recording apparatus of the present invention, it is the electrostatic latent image on the recording medium that determines the ON / OFF of the ink ejection. It is not necessary to individually apply a high voltage pulse to each of the electrodes, and it is possible to apply a pulse voltage to all the counter electrodes at the same time. Therefore, an individual high voltage pulse generation circuit or the like is unnecessary. Therefore, the structure of the ink ejection portion can be greatly simplified, and an ink ejection portion that requires a large-scale electrode such as a slit nozzle can be easily manufactured, which is a drawback of inkjet recording. The problem of nozzle clogging can be easily solved by adopting a slit jet nozzle that does not easily clog. Further, the problem of interference between adjacent electrodes, which is a drawback of slit jet recording, can be solved because all counter electrodes have the same potential.

Also, the problem of current leakage to the adjacent electrode through the ink liquid is eliminated, and in the conventional slit-jet recording, only oil-based ink using a petroleum-based solvent that has environmental problems and risk of fire due to ignition can be used. Although not available, water-based ink can be used.

Further, in addition to the pulse voltage applied to the counter electrode in the ink ejection portion at the time of recording, DC and AC bias voltages, which are impossible in the conventional slit jet recording, are applied to the counter electrode in the ejection portion in a superimposed manner. By doing
It is also possible to electrically vibrate the ink to facilitate the formation of a meniscus of the ink and to improve the recording speed.

[0025]

EXAMPLES Examples of the present invention will be described in detail below. (Embodiment 1) FIG. 1 is a sectional view showing a main part of an ink jet recording apparatus according to this embodiment, and FIG. 2 is a perspective view thereof.

The ink ejection section 1 comprises an ink ejection port forming substrate 11 and a slit-shaped ink ejection port forming upper plate 12, and the substrate 11 and the upper plate 12 constitute an ink holding section 13. Ink 1 is stored in the ink holding unit 13.
7 is held, and a slit-shaped ink ejection port 18 for ejecting ink is formed at the tip thereof.

A plurality of counter electrodes 15 and a common electrode 14 are formed on the ink discharge port forming substrate 11. The counter electrode 15 is formed by vacuum-depositing metal chrome on the ink discharge port forming substrate 11 and etching away the tip of the ink discharge port side in a pattern of 5 mm, and the width thereof is 60 μm. Further, the counter electrodes 15 were formed so that the array density was 8 lines / mm. The above-mentioned vapor-deposited metal chrome rear end portion is not etched, and the portion becomes the common electrode 14 for high voltage application. In this embodiment, an amorphous silicon nitride film is formed on each electrode in order to prevent the electrode from being corroded by the ink. This amorphous silicon nitride film is plasma CVD (Ch
The film is formed by the electrical vapor deposition method.

The ink ejection port forming upper plate 12 is placed on the ink ejection port forming substrate 11 provided with the counter electrode 15 and the common electrode 14 through the spacer 16 as described above, and the both plates are adhered and fixed to the ink ejection unit. Got 1.

In the ink holding portion 13 of the ink ejecting portion 1, an aqueous ink 17 (electrical conductivity of 0.06 [1 / (Ω
M)] and a viscosity of 1.75 × 10 ⁻³ [m ² / s]).

The recording medium 2 carrying an electrostatic latent image comprises a back electrode 21, a pyroelectric body 22 formed thereon, and a dielectric 23 serving as a protective layer for the back electrode.

In this embodiment, LiT is used as the pyroelectric body 22.
Composite of aO ₃ and polyvinylidene fluoride (pyroelectric coefficient 12n
C / cm ² · K) having a thickness of 8 μm, aluminum for the back electrode 21 having a thickness of 100 nm and polyethylene terephthalate having a thickness of 3.5 μm for the dielectric 23 serving as a protective film were used.

A recording head 3 is arranged on the opposite side of the recording medium 2 from the ink ejection section 1. In this embodiment, the recording head 3 is composed of a thermal head for thermal recording of 200 dpi.

The recording medium 4 is conveyed in close contact with the recording medium 2 during recording. In this example, a smooth recording paper having a thickness of 60 μm was used as the recording medium 4.

In such a structure, first, the recording cycle is 1 msec. , Pulse width 0.5 ms
ec. The recording medium 2 was heated by. At this time, the surface voltage of the pyroelectric material 22 on the surface of the recording medium was a high voltage with a potential peak of 700 V with respect to the back electrode 21. A DC bias voltage of 300 V was applied to the back electrode 21 during recording.

In the ink ejection section 1, the counter electrodes 15 are arranged so as to face each other with a distance of 500 μm from the tip of the recording head 3.
In synchronization with the pulse voltage application signal to the recording head 3 as a bias voltage for the common electrode 14 for high voltage application of the ink ejection unit 1, the pulse voltage 300V of the opposite electrode is 200V of the same polarity.
When applied by superimposing it on the DC voltage of
It is possible that ink droplets are ejected onto the surface of the recording medium on which the electrostatic latent image exists from 8 and recording can be performed on the recording medium (recording paper) 4 provided in contact with the recording medium 2. confirmed. (Embodiment 2) FIG. 3 is a sectional view of a main part of an ink jet recording apparatus according to this embodiment, and FIG. 4 is a perspective view thereof.

The basic structure of the ink ejection portion 1 is similar to that of the first embodiment, and includes an ink ejection port forming substrate 11 and a slit-shaped ink ejection port forming upper plate 12, and these substrates 11 are provided.
The upper plate 12 constitutes an ink holding portion 13. Ink 17 is held in the ink holding portion 13, and a slit-shaped ink ejection port 18 for ejecting ink is formed at the tip thereof.

A plurality of counter electrodes 15 and a common electrode 14 are formed on the ink ejection port forming substrate 11. The counter electrode 15 and the common electrode 14 are formed in the same manner as in the first embodiment, and the shape and size thereof are also the same as in the first embodiment.

Further, the ink ejection port forming upper plate 12 is provided with a second electrode 19 for applying a high voltage in a direction intersecting with the recording electrode 13. The second electrode 19 for applying a high voltage was previously formed by the same method as the electrode 15. Note that, also in this embodiment, in order to prevent the counter electrode 15 and the second electrode 19 for high voltage application from being corroded by the ink and the electric field,
An amorphous silicon nitride film is deposited on each electrode by plasma CVD.

Thus, the counter electrode 15 and the common electrode 14 are
The ink ejection port forming upper plate 12 was placed on the ink ejection port forming substrate 11 provided with the spacers 16 through the spacers 16, and both plates were bonded and fixed to obtain the ink ejection unit 1.

In the ink holding portion 13 of the ink ejection portion 1, the oil-based ink 17 (electrical conductivity 6 × 10 ^-8 [1 /
(Ω · m)] and a viscosity of 0.90 × 10 ⁻⁶ [m ² / s]).

The recording medium 2 carrying an electrostatic latent image is composed of a back electrode 21, a photoconductor 24 made of a photoconductive insulator formed thereon, and a dielectric 25 coated on the photoconductor. It has a cylindrical shape.

In this embodiment, the photoconductor 24 is a composite of CdS and polyester and has a thickness of 40 μm, the back electrode 21 is made of aluminum having a thickness of 100 nm, and the dielectric 25 serving as a protective film is used. A 25 μm thick transparent polyethylene terephthalate was used.

A recording head 3 is arranged on the opposite side of the recording medium 2 from the ink ejection portion 1. In this embodiment, the recording head 3 is composed of a 300 dpi electrophotographic LED head.

In this embodiment, an ink image is formed on the recording medium 2 in correspondence with the electrostatic latent image, and then the ink image is transferred onto the recording medium 4. As the recording medium 4, a smooth recording paper having a thickness of 60 μm was used.

In order to form an electrostatic latent image on the recording medium 2 with such a configuration, first, the surface of the dielectric 25 is positively charged. Next, the surface of the dielectric 25 is discharged, and at the same time, the recording head 3 irradiates the recording medium 2 with light to perform image exposure. Then, uniform electrostatic exposure is performed to form an electrostatic latent image. In this example, the light irradiation conditions for the recording medium were set to a recording period of 2 msec and a pulse width of 0.5 msec. When the electrostatic latent image was formed, the voltage on the surface of the dielectric 25 of the recording medium 2 was as high as the potential peak of 1300 V with respect to the back electrode 21.

The ink ejecting portion 1 is 5 from the front end of the recording medium 2.
Opposing electrodes 15 are arranged to face each other with an interval of 00 μm, and an AC bias voltage having a peak value of 50 V and a frequency of 4 kHz is applied to the high-voltage applying second electrode 19 of the ink ejecting unit 1 to electrostatically discharge the ink liquid. Giving vibration. Then, as a bias voltage for the high-voltage applying common electrode 14, a pulse voltage 300 of opposite polarity is synchronized with the pulse voltage applying signal to the recording head 3.
When V was applied, it was confirmed that ink was ejected from the ink ejection port 18 onto the surface of the recording medium on which the electrostatic latent image was present, and recording was possible. (Embodiment 3) FIG. 5 is a sectional view of a main portion of an ink jet recording apparatus according to this embodiment, and FIG. 6 is a perspective view thereof.

The basic structure of the ink ejection portion 1 is similar to that of the first embodiment, and includes an ink ejection port forming substrate 11 and a slit-shaped ink ejection port forming upper plate 12, and these substrates 11 are provided.
The upper plate 12 constitutes an ink holding portion 13. Ink 17 is held in the ink holding portion 13, and a slit-shaped ink ejection port 18 for ejecting ink is formed at the tip thereof.

A plurality of counter electrodes 15A and 15B are formed on the ink discharge port forming substrate 11, and a common electrode 14A corresponding to the counter electrode 15A is further formed. The common electrode 14B corresponding to the counter electrode 15B is formed from the substrate 11 to the spacer 16.
The counter electrodes 15A and 15B are formed by vacuum-depositing metallic chrome on the slit-shaped ink discharge port forming substrate 11 and etching it to remove it in a pattern, and the width thereof is set to 60 μm. Alternately formed on 11. The counter electrodes 15A and 15B were formed so that the arrangement density thereof was 8 lines / mm, and the rear end portions of these were made into separate high-voltage applying common electrodes 14A and 14B. In this embodiment also, the counter electrode 1 is exposed to the ink and the electric field.
For the purpose of preventing corrosion of 5A and 15B, an amorphous silicon nitride film is deposited on each electrode by plasma CVD.

In this way, the ink ejection port forming substrate 1 provided with the counter electrodes 15A and 15B and the common electrodes 14A and 14B.
Ink ejection port forming upper plate 12 on which spacers 16 are provided
Was placed, and both plates were bonded and fixed to obtain an ink ejection portion 1.

In the ink holding portion 13 of the ink ejection portion 1, the oil-based ink 17 (electrical conductivity 1.1 × 10 ⁻⁸ [1
/ (Ω · m)], viscosity 1.85 × 10 ⁻⁶ [m ² / s])
Was filled.

The recording medium 2 carrying an electrostatic latent image is composed of a back electrode 21, a photoconductor 24 made of a photoconductive insulator formed thereon, and a dielectric 25 coated on the photoconductor. It has a cylindrical shape.

In this embodiment, the photoconductor 24 is an n-type hydrogenated amorphous silicon film having a thickness of 1 μm, and the back electrode 21 is made of aluminum having a thickness of 1 mm.
As the dielectric 25 to be the protective film, transparent polyethylene terephthalate having a thickness of 25 μm was used.

A recording head 3 is arranged on the opposite side of the recording medium 2 from the ink ejection portion 1. In this embodiment, the recording head 3 is composed of a 300 dpi electrophotographic LED head.

In this embodiment, unlike the second embodiment, the direct recording method is adopted, and the recording medium 4 is conveyed in close contact with the recording medium 2 during recording. As the recording medium 4, a smooth recording paper having a thickness of 60 μm was used.

In order to form an electrostatic latent image on the recording medium 2 in such a structure, first, the surface of the dielectric 25 is positively charged. Next, the surface of the dielectric 25 is discharged, and at the same time, the recording head 3 irradiates the recording medium 2 with light to perform image exposure. Then, uniform electrostatic exposure is performed to form an electrostatic latent image. In this embodiment, the recording cycle is set to 1 msec and the pulse width is set to 0.5 msec. As for the voltage of the surface of the dielectric 25 of the recording medium 2 when the electrostatic latent image was formed, a high voltage with a potential peak of 1500 V was obtained with respect to the back electrode 21.

The ink ejecting portion 1 is 5 from the front end of the recording medium 2.
Opposing electrodes 15A and 15B are arranged to face each other with a space of 00 μm, and electrodes 14A and
An AC bias voltage having a peak value of 30 V and a frequency of 4 kHz was applied to 4B so that the mutual phase difference was 180 °, and electrostatic vibration was applied to the ink liquid. Then, when a pulse voltage of 300 V having a reverse polarity is applied to the common electrodes 14A and 14B for high voltage application in synchronization with the pulse voltage application signal to the recording head 3, the surface of the recording medium on which the electrostatic latent image is present from the ink ejection port. It was confirmed that the ink droplets were ejected onto the recording medium 4 and recording could be performed on the recording medium 4 directly above the recording medium 2. (Embodiment 4) FIG. 7 is a sectional view of a main part of an ink jet recording apparatus according to this embodiment, showing a recording apparatus using a serial type ink jet recording system.

The ink ejecting section 1 is basically constructed in the same manner as in the first embodiment. That is, the ink ejection port forming substrate 11
And the slit-shaped ink ejection port forming upper plate 12 are provided, and the ink holding unit 1 is formed by the substrate 11 and the upper plate 12.
3 are configured. Ink 17 is stored in the ink holding portion 13.
Is held, and a slit-shaped ink ejection port 18 for ejecting ink is formed at the tip thereof. Then, the counter electrode 15 and the common electrode 14 made of metallic chromium are formed on the substrate 11. The width of the counter electrode was set to 60 μm and the array density was set to 8 lines / mm. In this example, an amorphous silicon nitride film was deposited on the counter electrode 15 by plasma CVD in order to prevent the electrode from being corroded by the ink.

Thus, the counter electrode 15 and the common electrode 14 are
The ink ejection port forming upper plate 12 was placed on the ink ejection port forming substrate 11 provided with the spacers 16 through the spacers 16, and both plates were bonded and fixed to obtain the ink ejection unit 1.

In the ink holding portion 13 of the ink ejection portion 1, the oil-based ink 17 (electrical conductivity 1.8 × 10 ⁻⁷ [1
/ (Ω · m)] and a viscosity of 5.5 × 10 ⁻⁶ [m ² / s]).

In the recording medium 2 carrying an electrostatic latent image, a back electrode 21, a pyroelectric material 22 formed thereon, and further thereon, fine particles composed of hemispherical stainless fine particles having a diameter of 10 μm are mutually disposed. An insulated float electrode layer 26,
And a resistor layer 27 serving as a heating medium behind the back electrode.

In this embodiment, as the pyroelectric material 22, a copolymer of polyvinylidene fluoride and ethylene trifluoride (a pyroelectric coefficient of 8) is used.
nC / cm ² · K) having a thickness of 25 μm, aluminum for the back electrode 21 having a thickness of 100 nm, and the resistor layer 27 serving as the heating layer has a thickness of 15 μm for the carbon-containing polyaramid film (surface). A resistance of 600 ohms) was used.

A recording head 3 is arranged on the opposite side of the recording medium 2 from the ink ejection portion 1. In this embodiment, the recording head 3 is composed of 180 needle electrodes 31 and return electrodes 32 at 360 dpi. As the recording medium, a smooth recording paper having a thickness of 60 μm was used.

The recording cycle by the recording head 3 is 0.5 mse.
c, the needle electrode is driven with a constant current at a pulse width of 0.2 msec, and a current is passed through the resistor layer 27 of the recording medium 2 to cause the pyroelectric layer 2 to flow.
2 was heated. The current flows from the needle-shaped electrode 31 to the back electrode 21 through the resistor 27 and again to the return electrode 32 through the resistor 27. At this time, the float electrode 2 on the surface of the recording medium
The voltage of 6 became a high voltage with a potential peak of 500 V with respect to the back electrode 21.

In the ink ejecting section 1, the counter electrodes 13 are arranged so as to face each other with a distance of 300 μm from the tip of the recording head 3.
When a pulse voltage of 300V having a reverse polarity is superimposed and applied to a DC bias voltage of 200V having the same polarity in synchronization with the pulse voltage application signal to the recording head 3, the common electrode 14 for high voltage application of the ink ejecting unit 1 is applied. It was confirmed that the ink droplets were ejected from the ejection port 18 onto the surface of the recording medium on which the electrostatic latent image exists, and recording was possible.

The recording medium of this embodiment moves continuously after the ink is attached, and the ink on the surface of the recording medium is transferred from the recording medium onto the recording medium by pressing. The ink remaining on the recording medium is removed by a cleaner. (Embodiment 5) FIG. 8 is a perspective view showing an ink ejecting portion of an ink jet recording apparatus according to this embodiment, showing a recording apparatus using a serial type ink jet recording system.

The structure of the ink discharge port (slit) 42 in which the counter electrode 41 is formed on the inner surface is the same as that of the above-described embodiments, but in FIG. 8, one surface of the substrate on which the ink holding portion 44 is formed. It is characterized in that the piezo element 43 is bonded to. The piezo element 43 is electrically connected to the pulse generator 44 and deforms inward when a pulse is applied. The substrate forming the ink holding portion 43 is deformed inward,
The pressurized ink deforms the ink meniscus so as to project outward from the slit 42, the ink is ejected at that timing, and the ejection is continued thereafter. After the pulse voltage returns to the reference level, the substrate of the ink holding unit 43 returns to its original shape, and as a result, the negative pressure of the ink is forcibly stopped. In this way, by adding the function of applying pressure vibration from the outside, it is possible to improve the controllability of the start / stop of ink ejection.

Although the piezo element 43 is adhered to one place in FIG. 8, a plurality of small piezo elements are used to improve the response frequency of the piezo element and to make the distribution of pressure waves in the slit direction uniform. It is more desirable to bond and drive simultaneously. (Embodiment 6) FIG. 9 is a perspective view showing a slit portion of an apparatus in this embodiment, in which a slit 51 is provided with a porous film 5.
This is an example in which 2 is fixed. The pitch and size of the holes 53 are smaller than the resolution specified in the specifications of the recording apparatus. Film 5
2 can be easily manufactured by, for example, etching or electroforming. The film 52 is made of a material such as Teflon that is hard to get wet, or is subjected to a surface treatment to make the recording medium side water repellent.
As shown in FIG. 3, a meniscus 54 is formed in each hole 53, and it is possible to prevent ink from adhering to a non-hole portion of the film surface to form the same meniscus 55 as shown in FIG. It For this reason, the phenomenon in which the ink in the holes is attracted by the electric potential of the image pattern formed on the back electrode to be turned into particles occurs independently in each hole of the porous film.

In this embodiment, since the pitch and size of the holes are fine, the number of ink particles 62 is 1 as shown in FIG.
The pixel 60 is formed. For this reason, even if ink is not generated from one hole for some reason, pixels are formed by ink particles from other holes, and dot omission is unlikely to occur. As a result, one ink particle produces one
The reliability of the apparatus is improved as compared with the inkjet recording method for forming pixels.

In this conventional method, interference between adjacent holes, which is a cause of image disturbance in the conventional slit-jet method, and the flight direction and speed of particles generated by electric charges of other particles are disturbed. However, if a plurality of particles as a group adheres evenly to the image pattern forming portion of the back electrode, the function of the recording device is satisfied even if the behavior of each particle is slightly disturbed. In this respect, it is similar to the electrophotographic developing process. Therefore, a photoconductor may be used as the back electrode in addition to the pyroelectric body, and the invention can be applied to an analog copying machine in which reflected light of light applied to a document is directly applied to the photoconductor. Even in this case, the advantage of the present invention that a fixing device is not necessary is maintained, and therefore the energy consumption is smaller than that of the conventional analog copying machine.
The device can be downsized.

Although a porous film is used in this application example, the same effect can be obtained with a porous block. For the porous block, a spongy material such as a sponge, a sintered metal, or a mesh mesh can be used. The effect of the present invention can be obtained if the holes are minute holes such as rectangular or polygonal.

Although the present invention relates to an ink jet recording apparatus, the basic principle of the present invention can be applied to an electrophotographic recording apparatus. An example will be described below.

Since the electrophotographic recording apparatus is non-impact recording, it has features such as low noise, clear recording of characters, high recording speed, and relatively low running cost. Recently, it has been used as an output terminal device for office automation equipment, and its market is expanding rapidly. However, in such an electrophotographic recording apparatus, the toner image developed on the photosensitive member is transferred onto the recording paper by the transfer charger, but the transfer rate is generally about 80 to 90%, and the transfer residual toner is always present. Will occur. Furthermore, this transfer rate greatly changes depending on the characteristics of the recording medium such as environmental conditions such as temperature and humidity, the thickness and material of the paper used. from these things,
The toner left on the photoconductor needs to be separated from the surface of the photoconductor by a cleaner including a cleaning blade or the like. The cleaning blade is made of an elastic material such as rubber and strongly rubs the surface of the photoconductor. There is also a problem that the surface of the photoconductor is damaged by the cleaner and the life of the photoconductor is shortened. Further, the toner collected by the cleaner is difficult to use again because it is mixed with paper powder, and must be discarded as it is. That is, several 10% of all toner is discarded as waste toner.
Further, since the transfer rate changes, it is difficult to obtain an image with stable image quality.

In order to reduce the amount of waste toner, a cleanerless system has recently been developed in which the toner remaining on the photoconductor is reused. In the cleanerless system, the residual toner that has not been transferred is cleaned by the developing device and collected inside the developing device. The collected toner is reused for recording by the developing device again. By doing so, the cleaner unit can be omitted, and the device can be downsized. Further, since the waste toner is also eliminated, the toner is not wastefully used. However, since the recording paper and the toner come close to or come into contact with each other in the transfer unit, dust, dust, talc, or the like on the surface of the recording paper may be mixed in with the waste toner inside the developing device. In such a case, the charging characteristics of the toner may change and the recorded image may be deteriorated.

On the other hand, by using the basic principle of the present invention and using the method of directly adhering the toner onto the recording paper without providing the transfer unit, the electrostatic field leaking to the outside through the recording paper is used. By this, the toner of the developing device is attracted onto the recording paper, and an image according to the latent image is formed on the recording paper. By doing so, it is not necessary to transfer the toner from the photoconductor onto the recording paper, so that it is not necessary to use a transfer unit or a cleaner unit, and the electrophotographic printer can be downsized. . The greatest feature is that waste toner can be completely eliminated without reusing the toner. Due to this feature, the recording cost can be reduced as compared with the conventional non-reuse type, and the characteristics of the toner are not changed by the paper dust compared with the reusable type, so it is stable forever. There is a feature that can provide the image.

Examples of such an electrophotographic recording apparatus will be described below. (Embodiment 7) FIG. 12 is a view for explaining the outline of an electrophotographic printer according to this embodiment. In this electrophotographic recording apparatus, the surface of the photosensitive drum 100 is first charged with a negative charge by the charger 101 of the corona charger.
The entire surface is uniformly charged to about 700V. Next, the laser beam 102 is applied to the photosensitive drum 100 according to the image signal. Since the resistance of the photosensitive member is reduced only in the portion irradiated with light, the negative charge in the portion irradiated with the laser beam 102 is erased and an electrostatic latent image is formed. Here, the recording paper 105 is taken out from a paper cassette (not shown) by a paper feed roller or the like and conveyed to the vicinity of the photoconductor drum 100.

In the electrophotographic printer of this example, next, on the photosensitive drum 100 on which the electrostatic latent image is formed,
It is characteristic that the recording paper 105 is directly overlaid. When the recording paper 105 is superposed on the photoconductor drum 100, the developing device 103 is brought into a state of coming close to or in contact with the surface of the recording paper 105, and an electric field due to the latent image potential formed on the photoconductor drum 100 is generated. By the action, the toner moves from the developing device 103 side to the recording paper 105 side, and the toner is directly developed on the recording paper 105. That is, the toner, which is the colored fine particles negatively charged by the reversal development, is applied to the recording paper 105 corresponding to the portion of the electrostatic latent image on the photoconductor drum 100 where the negative charge is erased, by applying the developing bias. However, the electrostatic latent image is visualized.

The recording paper 1 on which the toner image is formed in this way
05, and finally, the recording paper 105 is heated and processed by the fixing device 111 including the heat roller 110.
The toner is fixed on the top, and the recording ends. In the fixing device, the heat roller 110 is provided on both sides or on the side that comes into contact with toner. Here, the toner adheres to the surface of the recording paper opposite to the photoconductor. Therefore, when one of the rollers of the fixing device is a heat roller, the side on which the toner adheres, that is, the lower roller in the drawing is the heat roller 110, which enables efficient fixing.
The photosensitive drum 100 is entirely exposed by an erasing lamp 109 composed of an LED array or the like to erase electric charges and is used for the next recording.

In such an electrophotographic recording apparatus, the transfer unit and the cleaner unit can be completely removed, and the apparatus can be made compact and inexpensive. Further, since the toner can be used in nearly 100%, the running cost can be reduced.

In this example, several developing methods can be considered. An example of the developing method will be described below with reference to FIG.

As the developing system, there are a contact developing system and a non-contact developing system. Basically, the non-contact developing is suitable as the developing system applied to the present embodiment, and the toner is caused to fly to develop on the recording paper. The method of doing is adopted.

FIG. 13 shows a developing device using a one-component non-magnetic toner which is an example of the non-contact developing system. An electrostatic latent image 200 is formed on the photosensitive drum 100. The electrostatic latent image 200 is formed by exposing the surface of the photoconductor drum in a negatively uniformly charged state so that the potential of the image portion is higher than that of the base portion. The recording paper 105 is brought into contact with the photosensitive drum 100.

The main part of the developing unit 103 is a developing roller 201 made of a conductive elastic body, a layer thickness regulating blade 202 made of an elastic body, and a toner reservoir 20.
3, a toner supply roller 204 and the like.
The developing roller 201 is rotating in the direction of the arrow in the figure, and is rotated to the contact portion between the recording paper 105 and the photosensitive drum with the toner layer having a thickness of about one toner layer being formed by the layer thickness regulating blade 202. Come on. Guide rings 205 are attached to both ends of the developing roller 201, and the diameter of the guide ring 205 is larger than the diameter of the developing roller 201. Therefore, the guide ring 205 is attached to the recording paper 105.
By pressing it against, the developing roller 201 can be kept a certain distance without contacting the recording paper 105.

A DC bias 207 and an AC bias 208 are applied to the developing roller 201 as a developing bias. The DC bias 207 has a voltage of about 500 to 1000 V, and this is the main bias for development. Since the toner is usually negatively charged, a negative voltage is applied to the developing roller 201 as the DC bias 207, and the toner flies to the photosensitive member in the portion where the negative charge of the electrostatic latent image 200 is erased. Then, reversal development 206 is performed. In this way, the development can be performed only with the DC bias 207, but
An AC bias 208 of about 5 to 2 kVpp is also applied. By applying this AC bias 207,
Since the toner constantly vibrates between the photoconductor 100 and the developing roller 201, there is an effect that an image having a stable density can be formed.

In a developing device of a type in which toner and recording paper are basically in contact with each other, unnecessary toner is clogged between fibers of the recording paper due to mechanical force, which causes scumming. However, since special paper or resin sheet whose surface is smoothed does not easily cause background stains, not only a non-contact type developing device but also a contact type developing device can be used. When there is unevenness on the surface of the recording paper like general plain paper, general contact development cannot be used. It is desirable to use a contact development method (for example, two-component magnetic brush development) in which the surface of the recording paper is not strongly rubbed. The two-component magnetic brush development is a commonly used development method and will be briefly described. It is composed of two components, a carrier made of iron powder and a toner, and these are triboelectrically charged to adhere the toner to the carrier by electrostatic force. The carrier attaches to the developing roller by magnetic force and forms a brush, forming a magnetic brush. The magnetic brush softly contacts the recording paper, and the toner adhering to the carrier moves toward the recording paper by the electrostatic force from the electrostatic latent image to form an image. Since the magnetic brush comes into soft contact with the recording paper, underground dirt is unlikely to occur even if plain paper is used. Further, since the recording paper and the toner can be brought very close to each other, there is an advantage that the latent image potential can be reduced as compared with the non-contact developing method. (Embodiment 8) FIG. 14 is a view for explaining the structure of a photosensitive drum 100 which plays an important role in the electrophotographic recording apparatus of this embodiment. The feature of this system is that the recording paper is directly superposed on the photosensitive drum 100 on which the electrostatic latent image is formed, and the toner image is directly developed on the recording paper. If the electric field due to the electrostatic latent image does not sufficiently leak to the outside of the recording paper 105, development is impossible. Therefore, the recording paper needs to be as close to the electrostatic latent image as possible. Since it is difficult to maintain a stable distance between the recording paper and the photoconductor drum, a method of pressing the paper on the photoconductor drum is suitable. In this case, if the recording paper is an insulating material such as an electrostatic recording paper or a resin film, there is no problem even if the recording paper is directly stacked on the photosensitive drum. That is, FIG.
As shown in 2, it is possible to realize an electrophotographic printer using an ordinary photosensitive drum.

However, when it is desired to use plain paper, there is a problem in bringing the recording paper into direct contact with the photosensitive drum. Paper is a material with high electrical resistance, but its electrical conductivity is several orders of magnitude higher than that of insulators, and it is easy for current to flow. Therefore, when the photosensitive drum on which the electrostatic latent image is formed and the plain paper are brought into direct contact with each other, a current flows through the recording paper and the electrostatic latent image is disturbed. Further, the paper has a large dependency on the resistivity, the humidity and the temperature, and the resistivity changes by several orders of magnitude with respect to the change of several tens of percent of the humidity. In order to prevent such a problem, the electrophotographic recording apparatus of the present invention uses a photosensitive drum having an insulating layer formed on the photosensitive layer. That is, as shown in FIG. 3, the photosensitive drum 100 of the type in which the photosensitive layer 121 is formed on the conductive metal drum 120 and the insulating layer 122 is further formed thereon is used. Here, as the photoconductor layer 11, all ordinary photoconductors such as Se-based, a-Si, and OPC can be used. Of course, the photoconductor layer 121 may have a multi-layer structure, and may be divided into, for example, a carrier generation layer and a carrier transport layer. The inner structure may be any structure, but it is necessary that the insulating layer 122 is formed on the outermost portion that contacts the recording paper. (Embodiment 9) FIG. 15 is a view for explaining the outline of an electrophotographic printer according to this embodiment, and particularly considers a portion where toner is fixed on a recording sheet. The recording sheet on which the toner image is formed is finally fixed and the recording is completed. Therefore, as shown in FIG. 12, near the exit of the recording paper,
A fixing device is required. Recording paper 105 and photoconductor drum 10
0 is once in contact, but will be separated from the photoconductor drum 100 after the toner image is formed. The toner adheres onto the recording paper 105 due to the electrostatic force of the latent image, but when the recording paper 105 and the photoconductor drum 100 are separated, the electrostatic force due to the electrostatic latent image disappears. Actually, the toner adheres to the recording paper even if the photosensitive drum recording paper is peeled off due to a van der Waals force, a polarization force, or a mechanical force such as friction with the recording paper. However, when a large mechanical vibration or the like occurs, the toner image may be disturbed.

In order to solve such a problem, FIG.
In the apparatus of No. 5, before the recording paper 105 is separated from the photoconductor drum 100, the toner is applied to the recording paper 1 by the hypothetical attachment roller 210.
I will wear it on top of 05. This hypothetical wearing roller 210
Is pressed against the recording paper, it plays a role of fixing the toner on the recording paper 105 by pressure into the surface of the recording paper by an unstable electric force so that the toner does not fall off by some impact. have. When the recording paper 105 is peeled off from the photoconductor drum 100 in such a presumed state, the toner is prevented from falling before reaching the fixing unit 111 and the toner image is disturbed.

The hypothetical fixing roller may be a rigid roller for pressure fixing or a roller for heat fixing. However, since full-scale fixing is performed by the fixing device 111, the hypothetical fixing roller 210 may be simple. As long as it is a roller for pressure fixing, even if it is a soft roller having elasticity to some extent, it does not matter if it is assumedly attached. Further, even when a heat roller for heat fixing is used, it is not necessary to raise the temperature to such a high temperature because it is sufficient that the toner can be temporarily fixed. Further, in order to prevent the toner from adhering to the hypothetical fixing roller 210, if the voltage of the same polarity as the toner is applied to the hypothetical fixing roller 210, the toner can be fixed more beautifully.

FIG. 16 shows another example. In this embodiment, the recording sheet 1
In this system, 05 is completely fixed before being separated from the photosensitive drum 100. By doing so, it is possible to realize the downsizing of the recording apparatus. Also in this case, the fixing roller 211 may be a heat roller or a pressure fixing roller. However, unlike the hypothetical fixing described above, a sufficient fixing strength is required, so that the heat roller requires a high temperature of at least 100 ° C. or higher, and in the case of pressure fixing, a rigid roller is required. (Embodiment 10) Electrophotographic recording apparatuses are also roughly classified into some, but the above-mentioned examples are all examples of laser printers. A printer that records an electrostatic latent image with light, such as a laser printer, can be classified as an optical printer and occupies most of the electrophotographic printer. In addition to laser printers, heads such as LEDs, ELs, phosphors, and liquid crystals can be classified as optical printers.

On the other hand, there is an electrophotographic printer which directly records an electrostatic latent image by using ions on an insulator. Such a method is called an ion flow recording method or an ion deposition recording method. This embodiment shows an example in which the present invention is applied to ion deposition recording.
FIG. 17 is a diagram for explaining the outline of the electrophotographic printer according to the present embodiment. The basic configuration is the same as that of the embodiment shown in FIG. 15, but the method shown in FIGS. 12 and 16 may be used. However, in comparison with the fact that the portion for recording the latent image is light, in this embodiment the ion head 22
The difference is 0.

In the ion deposition recording, a recording drum 221 made of an insulating material is used. This recording drum 2
21 is first uniformly charged by the charger 222. The charger 222 may be a corona charger as shown in FIG. 12, but in this case, a solidified ion generator was used. The ion head 220 has a charger 222 inside.
There is an ion generator having substantially the same structure as described above, and the ions generated here are controlled by control electrodes based on an image signal to record an electrostatic latent image on the recording drum 221. For details on ion deposition recording,
It is described in Japanese Patent Application Laid-Open No. 04-211971. When the electrostatic latent image is formed on the recording drum in this manner, the recording paper 105 is then brought into contact with the recording drum 221, and thereafter, the recording paper 105 is contacted by the same method as described above. A toner image is formed directly on top.

The major difference from the above-mentioned optical printer is that
That is, the recording drum 221 made of an insulating material is used.
Therefore, if the recording paper 105 is an insulator, (a) in FIG.
The method shown in is also sufficient. However, when the recording paper is plain paper, the electrostatic latent image formed on the insulating recording drum 221 is disturbed due to the conductivity of the plain paper. In the case of an optical printer, this problem can be addressed by using a photoreceptor as shown in FIG. 14 in which an insulating layer is formed between the photoreceptor and the recording paper. However, in the case of ion deposition recording, it is necessary to directly form an electrostatic latent image on the surface of the insulator with ions and then to insulate the recording sheet 105 to bring it into contact with the surface.

Therefore, a printer is constructed as shown in FIG. In other words, using the insulator film 223,
The ion recording head 2 is uniformly charged by the charger 222.
First, the insulating film 223 is brought into contact with the recording drum 221 on which the electrostatic latent image is formed on the recording drum 10.
5 is brought into contact with the insulating film 223 to perform development. By doing so, in the case of ion deposition recording, the toner image can be directly formed on the plain paper without disturbing the electrostatic latent image. Although not shown, the insulating film 223 is in the form of an endless beetle, and it is desirable that the insulating film 223 be used again after being discharged by a charger or the like. In the case where the structure is not endless, the insulating film 223 is wound between the take-up reel and the pay-out reel, and there is also a method of reciprocating between these reels to use many times. The insulating film is not particularly limited, but a PET film or the like that can be obtained at low cost can be used. (Embodiment 11) In the embodiments described so far, the case where an electrostatic latent image is recorded with a non-magnetic toner has been described, but an embodiment using a magnetic toner is also conceivable. In this case, a magnetic latent image is formed instead of the electrostatic latent image, and this is developed with magnetic toner. The characteristic of the magnetic latent image is that it is very stable against changes in environmental temperature. The electrostatic latent image has a large potential change due to the influence of humidity and the like, whereas the magnetic latent image does not have such a problem. However, since the magnetic material is generally black, there is a problem that even if color recording is performed using colored magnetic toner, a beautiful full color cannot be produced due to color superposition. Still, in the case of black-and-white recording, multi-color recording, or full-color recording by juxtaposed mixing, the magnetic toner can sufficiently withstand use. FIG. 18 shows an example using a magnetic toner.
A further major feature of the magnetic latent image is that since the relative magnetic permeability of paper and resin is almost 1, even when recording paper is inserted between the recording drum and the developing unit, the magnetic latent image shows these characteristics. That is, it is hardly affected by the recording paper. This is because the relative permittivity of paper or resin is, for example, about 2 to 3 and is different depending on the material, so that the electrostatic latent image formed on the photoconductor is slightly blurred on the recording paper. It is a feature. That is, when the magnetic latent image is used, stable image formation can be performed without being influenced by the environment or the material of the recording paper.

Here, a magnetic drum 230 having a surface coated with a magnetic material as shown in FIG. 18 is used. The magnetic latent image previously recorded on the magnetic drum 230 is first degaussed by the degaussing head 231. As the degaussing head 231, a magnetic head capable of electrically controlling the generation of a magnetic field, or a permanent magnet constantly generating a magnetic field can be used, and the magnetic field generated by the degaussing head 231 can be used for the magnetic drum. A remanent magnetization pattern in the same direction is formed on 230 and demagnetized. Next, the magnetic head 232 forms a magnetic latent image on the magnetic drum 230 according to the image data. FIG.
The magnetic recording head 232 shown in FIG. 2 performs recording in a horizontal plane, and a plurality of unit heads as shown in the drawing are arranged in the direction perpendicular to the paper surface to form the recording head 232. Using such a recording head 232, a residual magnetization pattern as indicated by a small arrow in FIG. 7 is recorded to form a magnetic latent image 233.
In the magnetic latent image 233, the magnetization pattern is reversed at the place where the image point is desired to be recorded, and the same magnetization pattern is formed when the image point is not recorded. The magnetic drum 230 on which such a magnetic latent image 233 is formed is rotated to the developing device 234 while being pressed against the recording paper 105. The basic structure of the developing unit 234 is a magnet roll 235 in which N and S magnetic poles are alternately formed, and a sleeve 236 made of a non-magnetic material outside the magnet roll 235. The magnetic toner adheres to the magnet roller 235 due to the magnetic force, and is conveyed on the sleeve 236 as the magnet roller 235 rotates.
The conveyed magnetic toner comes into contact with the magnetic drum 230 via the recording paper 105. A magnetic field formed by the magnetic latent image 233 formed on the magnetic drum 230 passes through the recording paper and leaks, and the magnetic toner is attracted to the magnetic field, so that the recording paper 105 is developed. After the toner image is formed on the recording paper, it is fixed on the recording paper in the same manner as described above.

In this embodiment, as the developing device, the magnet roller is rotated to convey the toner, but the sleeve rotation method has the same effect. Further, although an example in which the magnetic toner is attached to the developing roller by magnetic force is shown, a method of attaching the magnetic toner to the developing roller by electrostatic force and conveying the magnetic toner may be used. Further, in this embodiment, the method of forming the magnetic latent image in the horizontal plane has been described, but perpendicular recording may be performed. (Embodiment 12) This embodiment is an example in which an electrostatic latent image is used again, but is characterized by a method of forming an electrostatic latent image. The electrophotographic recording apparatus of this example is shown in FIG. In this electrophotographic recording apparatus, the pyroelectric belt 240 and the thermal head 24 are
1 and the recording paper 105 are pressed against the pyroelectric belt 240. The pyroelectric material is a material that generates a voltage by generating polarization inside the material when heated. That is, by selectively heating the pyroelectric belt 240 according to the image with the thermal head 241, an electrostatic latent image is formed on the pyroelectric belt 240. The electric field leaking from the electrostatic latent image acts on the toner on the developing device 242 to attract the toner onto the recording paper 105, whereby a toner image is directly formed on the recording paper 105. Although not shown, the recording paper 105 on which an image is formed is finally fixed and recording is completed. The pyroelectric belt 240 is configured to be used endlessly or repeatedly, and is cooled by a natural cooling device or a forced cooling device so that the potential is erased and then used again. Note that FIG. 19A shows the pyroelectric belt 2
This is an embodiment in which the thermal head 241 is heated from the back side of 40, and is characterized in that latent image formation and development can be performed almost simultaneously. On the other hand, FIG. 19B shows the pyroelectric belt 24.
It is a method of heating the front side of 0. Although the latent image is formed on the surface side of the pyroelectric belt 240, it has a feature of compensating for the blurring of the latent image due to the diffusion of heat, though there is a drawback that it takes time from the formation of the latent image to the development.

As described above, the present invention can also be applied to an electrophotographic recording device that heats a pyroelectric material to form an electrostatic latent image. Although the thermal head is used as the method for heating the pyroelectric body in this embodiment, an optical head may be used. For example, a method in which a pyroelectric surface is scanned with laser light or the like and heated with laser light to form an electrostatic latent image is also conceivable. When recording with an optical head, it is ideal to form a light absorbing layer on the opposite side of the surface of the pyroelectric material that contacts the recording paper so that the conversion efficiency from light to heat is improved. is there. Further, in the embodiment of FIG. 19, a belt-shaped medium is used as the medium for forming the latent image, but like the embodiments up to FIG. 18, it may be formed in a drum shape. Even if it is a drum shape, there is no problem as long as the temperature of the pyroelectric body is sufficiently lowered before it is used again.
On the contrary, even in the embodiments up to FIG. 18, there is no problem even if a belt-shaped medium, that is, a photosensitive belt, an insulating belt, a magnetic belt or the like is used.

[0096]

As described in detail above, according to the present invention,
An inkjet recording device that can adopt an electrostatic acceleration type inkjet recording system that is compact and has excellent operability and that can form a recording pattern with high accuracy that was impossible with the conventional inkjet recording system paste printing system. Can be provided. Further, according to the ink jet recording method of the present invention, it is possible to perform recording without using an expensive high-voltage driving IC, large-scale microfabrication of a complicated structure such as a resistor / electrode, and to construct an inexpensive system. Is possible.

Further, it is also possible to use a water-based ink having a low electric resistance, which was impossible in the conventional slit-jet type recording apparatus of the present invention. For this reason, it is possible to provide a safe and hygienic recording apparatus that is free from environmental problems such as a bad odor caused by the oil-based ink, and from causing the oil-based ink to catch fire and cause a fire. Further, since the water-based ink has a high surface tension as compared with the oil-based ink, it is easy for the particles to be fine particles. Therefore, it is possible to print a higher definition image at high speed.

[Brief description of drawings]

FIG. 1 is a sectional view showing an inkjet recording apparatus according to an embodiment of the present invention.

2 is a perspective view of the device of FIG. 1. FIG.

FIG. 3 is a sectional view showing an inkjet recording apparatus according to another embodiment of the present invention.

4 is a perspective view of the device of FIG.

FIG. 5 is a sectional view showing an ink jet recording apparatus according to still another embodiment of the present invention.

6 is a perspective view of the device of FIG.

FIG. 7 is a sectional view showing an ink jet recording apparatus according to still another embodiment of the present invention.

FIG. 8 is a perspective view showing an ink ejection portion of an inkjet recording apparatus according to still another embodiment of the present invention.

FIG. 9 is a diagram showing ink ejection ports of an inkjet recording apparatus according to still another embodiment of the present invention.

FIG. 10 is a cross-sectional view of the ink ejection port portion shown in FIG.

FIG. 11 is a diagram showing a pixel portion recorded by using the device shown in FIG.

FIG. 12 is a structural diagram showing an example in which the principle of the present invention is applied to an electrophotographic recording device.

FIG. 13 is an explanatory view showing an example of a developing device of an electrophotographic recording apparatus according to another example.

FIG. 14 is an explanatory diagram of an example of a photosensitive drum used in an electrophotographic recording apparatus according to another example.

FIG. 15 is a structural diagram of an electrophotographic recording apparatus which is another example and performs hypothetical attachment.

16 is a structural diagram of a fixing type electrophotographic recording apparatus which is a modified example of FIG.

FIG. 17 is a structural view of an ion deposition type electrophotographic recording apparatus which is still another example.

FIG. 18 is a structural diagram illustrating still another example in which the present system is applied to a magnetic recording device which is an example of electrophotographic recording.

FIG. 19 is a structural view of an electrophotographic apparatus, which is another example, in which the recording drum is formed of a pyroelectric material.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ink ejection part, 2 ... Recording medium, 3 ... Recording head, 4
Recording medium, 11 ... Ink ejection port forming substrate, 12 ... Ink ejection port forming upper plate, 13 ... Ink holding section, 14, 14
A, 14B ... Common electrode, 15, 15A, 15B ... Counter electrode, 16 ... Spacer, 17 ... Ink, 18 ... Ink ejection port, 19 ... Second electrode for voltage application, 21 ... Back electrode, 22
... Pyroelectric material, 23, 25 ... Dielectric material, 24 ... Photosensitive material, 26 ...
Float electrode, 27 ... Resistor layer, 31 ... Needle electrode, 32
… Return electrode.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Takayama 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki City, Kanagawa Prefecture Corporate Research & Development Center, Toshiba Corporation (72) Inventor Sakae Tamura Komukai-Toshiba, Kawasaki-shi, Kanagawa Prefecture Town No. 1 Incorporated company Toshiba Research and Development Center (72) Inventor Tsutomu Saito No. 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki City, Kanagawa Prefecture Incorporated company Toshiba Research and Development Center (72) Inventor Hideki Nukita Kawasaki, Kanagawa Prefecture Komukai-Toshiba-cho No. 1 Inside the Toshiba R & D Center Co., Ltd. (72) Inventor Shuzo Hirahara No. 1 Komukai-Toshiba Town Co., Ltd. Kawasaki City Kanagawa

Claims (1)

[Claims] 1. A recording medium carrying an electrostatic latent image and a recording medium which is provided in a non-contact state so as to face the recording medium, and is soaked in an ink liquid holding portion and the ink liquid in the ink liquid holding portion. An ink liquid ejecting section having at least one counter electrode provided and an opening for ejecting the ink liquid; and ink by an electric field between the electrostatic latent image on the recording medium and the counter electrode. A recording apparatus, wherein liquid is discharged from the opening.