JPH10235868A - Recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To process in a noncontact manner at high speed by forming and separating by a predetermined distance in a plane direction at least a source electrode and a part for supplying electric charges to ink. SOLUTION: In a state with a high voltage applied between a source electrode 3 and a counter electrode 6 from a driving power source 8, a photoconductive body 2 is irradiated with a write light 10 by a light projection means 7 from the side of the source electrode 3. As a result, a resistance value at a projected area of the photoconductive body 2 is decreased and consequently a light current flows at the area thereby electrically connecting the source electrode 3 and an ink chamber 5. Since electric changes are injected to the ink chamber 5, the ink receiving a Coulomb's force flies to the counter electrode 6 from an ink jet part 11, adheres and is fixed to a medium 9 to be recorded. Not only the electric charges are directly injected to the ink chamber 5 from the photoconductive body 2, but a terminal point of the source electrode 3 as a charge injection source and a charge injection part are arranged via a predetermined distance in an in-plane direction of a film of the photoconductive body 2. Moreover, the source electrode 3, ink jet part 11 and counter electrode 6 are set linearly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a printing industry that requires high-speed output of high-quality images, an office, a printer industry based on personal requirements, a low-cost general-purpose output device using various recording media, and the like. The present invention relates to a recording head used in a recording apparatus for obtaining an output image on a recording medium that can respond to a wide range of needs up to the consumer goods industry that demands a printer.

[0002]

2. Description of the Related Art As shown in FIG. 10, a conventional electrostatic acceleration type ink jet recording apparatus [Takami Uehara: "Electrostatic acceleration type ink jet recording apparatus", Japanese Unexamined Patent Publication No. 2-72960] has a slit shape. Ink jet port 1010, the upper plate 1012 and the substrate 1011 forming the ink jet port 1010, and the substrate 101
1, a recording electrode 1014 arranged in recording pixel units,
A counter electrode 1002 disposed opposite to the ink ejection port 1010, a recording paper 1005 moving along the counter electrode 1002, and a driving power supply (HVP) for supplying a high voltage to a selected electrode of the recording electrode 1014. ), And in the ink recording head 1001 having a photoconductor 1016 provided between the recording electrode 1014 and the ground electrode 1015, the oil-based ink 1018 is filled until reaching the ink ejection port 1010, and the recording electrode 1014 By applying a voltage pulse corresponding to an image pixel between the opposing electrodes 1002, the oil-based ink 1018 is ejected and flies, and adheres and permeates on the recording paper 1005 to obtain a desired output print or image.

In particular, in the conventional example shown here, the recording electrode 1
By connecting the photoconductor 1016 with light corresponding to an image pixel signal by connecting the photoconductor 1016 to the ground electrode 1015 via a photoconductor 1016, the photoconductor 1016 can be easily connected without using a high withstand voltage driving integrated circuit. A voltage pulse corresponding to an image pixel can be generated between the recording electrode 1014 and the counter electrode 1002. Further, in this example, the light corresponding to the image pixels can be easily obtained by the light signal irradiating unit 1004 which can collect the light from the original 1019 by the selfoc lens 1020. In this conventional example, at least the recording electrode 101
Needless to say, 4 is divided and formed corresponding to the recording image pixels.

[0004] Such a conventional electrostatic acceleration type ink jet recording apparatus (hereinafter, referred to as a slit jet method) is
By replacing the nozzles used for inkjet recording with the elongated slit-shaped ink ejection ports 1010, the resolution of the nozzles is not restricted, and
Cleaning of the ink ejection port 1010 can be facilitated. Further, in the slit jet method, color output printing can be easily obtained by using a plurality of the ink jet ports 1010 and injecting the oil-based ink 1018 of a different color into each ink jet port 1010.

[0005]

The conventional ink jet recording method has the following problems. (1) Since nozzles are used for ejecting ink, it is difficult to improve the resolution. (2) There are two types of inkjet recording systems: continuity type and on-demand type. The continuity type has a high recording speed, but it is difficult to simplify the device to collect unnecessary ink. Although the device configuration is simplified, it is difficult to increase the recording speed.

The following problems have been encountered in the slit jet method for solving the above-mentioned problems of the ink jet recording method. (1) It is difficult to improve the resolution because the recording electrodes corresponding to the recording pixel units are arranged to make the ink jump. (2) When a high voltage is applied to the recording electrode, a discharge phenomenon occurs between the selected recording electrode and the non-selected recording electrode when both electrodes are adjacent to each other. Therefore, optimization of ink characteristics, application voltage and timing thereof Difficult to control. (3) Since a high voltage is applied while the recording electrode is in contact with the ink, the recording electrode is greatly deteriorated.

It is therefore an object of the present invention to provide a recording head capable of performing high-definition and high-quality printing at high speed and capable of performing non-contact output printing regardless of the shape of a recording medium. .

[0008]

In order to solve the above-mentioned problems, a recording head according to the present invention optically switches a photoconductor provided between a source electrode serving as a charge supply source and ink. As a result, electric charges are supplied from the source electrode to the ink, and the ink supplied with the electric charges is separated and fly from a predetermined portion by electrostatic force. The specific configuration is shown below. [Configuration 1] A charge is supplied to a predetermined ink portion by optically switching a photoconductor provided between a source electrode, which is a charge supply source, and ink, and the ink portion to which the charge has been supplied is charged by electrostatic force. In a recording head that separates and flies, at least a source electrode and a portion that supplies electric charges to ink are formed so as to be separated by a predetermined distance in the plane direction. [Arrangement 2] In the recording head of Arrangement 1, at least the source electrode and the portion where the charged ink is separated and fly are separated by a predetermined distance in the ink flying direction. [Configuration 3] In the recording head according to Configuration 1 or 2, the substrate, the source electrode, the photoconductor, the ink supply path for supplying ink to the insulating film and the photoconductor, and the ink supply path formed on the photoconductor. An ink chamber, a counter electrode disposed at a predetermined distance from the ink chamber, a power supply for applying a voltage between the source electrode and the counter electrode, and a light for irradiating the photoconductor with light corresponding to a desired image pixel. At least an irradiation means. [Structure 4] In the recording head according to Structure 3, the ink chamber has an ink flying portion formed with a gap separated from the source electrode by a predetermined distance, and a portion irradiated with light corresponding to an image pixel is formed by the source electrode and the photoconductor. And at least part or all of a predetermined gap provided between the boundary between the photoconductor and the ink chamber. [Arrangement 5] In the recording head according to any one of Arrangements 3 and 4, the substrate is made of a transparent substrate and arranged so that light emitted from the light irradiating means is emitted from the transparent substrate side. [Arrangement 6] In the recording head according to any one of Arrangements 1 to 5, at least a gap between the ink and the source electrode is protected by an insulating film. [Arrangement 7] In the recording head according to any one of Arrangements 2 to 6, a part of the ink chamber is formed by a substrate, a photoconductor, a source electrode, or a wall provided on an insulating film. [Arrangement 8] In the recording head according to any one of Arrangements 2 to 7, a top plate having a slit hole formed corresponding to the ink flying portion is provided so as to sandwich the ink chamber between the top plate and the photoconductor. [Configuration 9] In the recording head according to any one of Configurations 2 to 8, the source electrode is formed linearly. [Configuration 10] In the recording head according to any one of Configurations 2 to 8, the source electrode is formed in a ladder shape. [Configuration 11] In the recording head according to any one of Configurations 2 to 8, the source electrode is formed in a comb shape. [Configuration 12] In the recording head according to any one of Configurations 2 to 8, the source electrode is formed in an irregular manner. [Configuration 13] In the recording head according to any one of Configurations 2 to 12, the photoconductor is divided and formed. The above configuration has solved the above problem.

[0009]

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 8 is an explanatory diagram schematically showing the basic configuration of the recording head of the present invention and the operation of each component. FIG. 9 is an explanatory diagram extracted to show some names and parts of FIG.
A and C are shown. Here, reference numerals shown in FIGS. 8 and 9 denote 1 a substrate, 2 a photoconductor, 3 a source electrode, 4 an insulating film, 5 an ink chamber, 6 a counter electrode, 7 a light irradiation means, and 8 a light irradiation means. A drive power source, 9 is a recording medium, 10 is a writing light, 11 is an ink jetting part, 12 is a top plate, 13 is a wall, and 14 is an electric field.

First, the basic configuration of the recording head according to the present invention will be described. In the basic configuration of the recording head of the present invention shown in FIG. 8, a photoconductor 2 is formed on a substrate 1 made of glass, transparent plastic, or the like. In addition, a metal material such as aluminum, chromium, or gold, or ITO (Indium-T
A source electrode 3 (see FIG. 9) made of a metal oxide conductive film such as in-oxide, a conductive polymer material, or the like is formed. Here, it goes without saying that the photoconductor 2 may be formed after the source electrode 3 is formed on the substrate 1. Next, an insulating film 4 (see FIG. 9) is formed on the source electrode 3 so as to completely cover the end point (part A shown in FIG. 9). That is, the insulating film 4 has a form in which the source electrode 3 and the ink chamber 5 are insulated. The insulating film 4 may be formed using a polymer material such as an acrylic resin, a polyimide resin, a polyethylene resin, or a rubber resin, or an insulating material such as silicon dioxide or silicon nitride. . Further, the top plate 1 having a slit-shaped opening held by the wall 13 is provided on the insulating film 4.
2 are installed. An area surrounded by the top plate 12, the wall 13, the insulating film 4, and the photoconductor 2 becomes the ink chamber 5. Here, the slit-shaped opening formed in the top plate 12 is located on a straight line connecting the source electrode 3 and the counter electrode 6, and the meniscus of the ink in the ink chamber 5 formed in this opening is ejected. It becomes part 11. In addition, the top plate 1
2 can be formed using a polymer material such as an acrylic resin, a polyimide resin, or a polyethylene resin, or an insulating material such as glass or ceramic. The ink chamber 5 has a channel for supplying ink to the slit-shaped opening, and the ink is supplied to the ink chamber 5 through an external ink supply unit. As the photoconductor 2, a silicon-based optical semiconductor such as hydrogenated amorphous silicon (hereinafter abbreviated as a-Si: H) formed by plasma CVD or reactive sputtering, or CdSe or CdTe is used.
For example, a chalcogenide-based optical semiconductor such as, or an organic optical semiconductor (hereinafter, abbreviated as OPC) can be used.

In the recording head of the present invention, a counter electrode 6 is provided so as to face the slit-shaped opening, and the counter electrode 6 and the source electrode 3 are electrically connected to a driving power source 8. I have. Here, the slit-shaped opening, that is, the ink ejection portion 11 is formed on a straight line connecting the source electrode 3 and the counter electrode 6, so that the electric field acting on the ejected ink can be given linearly, that is, efficiently. Also,
In the example shown in FIG. 8, an air layer is provided between the counter electrode 6 and the ink ejection unit 11 or the top plate 12, and a recording medium is provided between the air layer and the ink ejection unit 11 or the top plate 12. By inserting the ink, the ejected ink is attached to the recording medium, and a dot pattern corresponding to a desired image pixel is recorded.

Next, the operation of the recording head of the present invention will be briefly described. A driving power supply 8 applies a DC voltage of 1 to 5 kV between the source electrode 3 and the counter electrode 6. The voltage applied at this time varies depending on the structure and dimensions of the recording head or the physical properties of the ink. At this time, the electric charge (in this case, electrons) supplied from the driving power supply 8 is transmitted through the source electrode 3 and reaches an end thereof (part A shown in FIG. 9). Since the source electrode 3 is covered with an insulating film made of an acrylic polymer or the like, its charge is
Then, the ink passes through the photoconductor 2, passes through the ink chamber 5 from the vicinity of the end of the insulating film 4 (the portion C shown in FIG. 9), and accumulates in the ink ejection unit 11. At this time, if there is no external light irradiation, the volume resistance of the photoconductor 2 is 10E9 to 10E11Ωc.
m. Furthermore, the counter electrode 6 and the ink ejection portion 11
Until the air layer of 0.2 to 1 mm exists, and a recording medium such as printing paper is also inserted, the resistance value during this period is significantly larger than the resistance values of other components. Has become. Therefore, at this time, most of the DC voltage applied by the drive power supply 8 is divided into the air layer. The magnitude of the drive voltage divided into the photoconductor 2 and the ink chamber 5 varies depending on the thickness of the photoconductor 2 and the distance between the portions A and C, and depends on the width and height of the ink chamber 5. Is also different. In such a state, the light irradiation means 7
The writing light 10 is applied to the portion B of the photoconductor 2 shown in FIG.
Is irradiated, the volume resistance value is reduced by about 10E3 to 10E5 of the volume resistance value at the time of non-irradiation only in this irradiated portion,
As a result, the ink is injected from the end of the source electrode 3 (part A shown in FIG. 9) into the ink chamber 5 through the region B of the photoconductor 2 and the end of the insulating film 4 (part C shown in FIG. 9). The charge amount increases. The injected charges are attracted to the counter electrode 6 side together with the ink by the electric field 14 from the counter electrode 6, and as a result, the radius of curvature of the interface of the ink ejection section 11 increases, and the charges concentrate on the interface of the ink ejection section 11. Then, a large suction force is received from the counter electrode 6. This process continues one after another, and the ink extends to the counter electrode side, and finally separates from the interface of the ink ejection portion 11, flies toward the counter electrode 6, and further adheres to the surface of the recording medium 9. Fixed. This process continues even after the irradiation of the writing light 10 from the light irradiating means 7 is completed, provided that a sufficient charge has been injected to cause the ink to fly.

In this manner, the writing light 10 corresponding to the image pixel is successively irradiated with the beam diameter corresponding to the dot diameter to be caused to fly, so that the amount of ink corresponding to the desired image pixel is caused to fly and the recording is performed. It can be attached and fixed to the medium. The recording head of the present invention is characterized in that the photoconductor 2
At the same time as directly injecting the electric charge into the ink chamber 5, the end point of the source electrode 3 (part A in FIG. 9) and the electric charge injection part (part C in FIG. The source electrode 3 is arranged at a predetermined distance in the direction.
And the ink ejection section 11 and the counter electrode 6 are installed in a straight line. If the charge injection portion of the source electrode 3 serving as the charge injection source and the photoconductor 2 are simply placed one on top of the other, the structure is such that the ink chamber 5 and the source electrode 3 are separated by the photoconductor 2, and the movement of the charge is caused by the photoconductor. It will be done in the direction perpendicular to the body membrane. On the other hand, since a DC voltage of 1 to 5 kV is applied to the source electrode 3 and the counter electrode 6 as described above, a high voltage of about 100 to 500 V is applied to the photoconductor 2. Therefore, for example, if the photoconductor 2 is a-S
i: H, the film thickness is about 2
If the thickness is not more than 0 μm, an appropriate optical switching function cannot be obtained. This is because a as the photoconductor 2
The production time of -Si: H extends from several hours to several tens of hours, which causes an increase in price. Furthermore, thin-film photoconductors such as OPC tend to cause pinholes in the film, which is a factor that reduces the yield. However, as shown in the present invention, the charge is directly injected from the photoconductor 2 into the ink chamber 5, and at the same time, the distance between the charge injection source and the end point of the source electrode 3 (near point C in FIG. 4) is substantially reduced. This is equivalent to the thickness of the photoconductor 2.

For example, when a-Si: H is used as the photoconductor 2, the distance between the charge injection point (A in FIG. 9) and the charge discharge point (C in FIG. 9) is set to 20 to 50 μm. Thereby, the same effect as when a-Si: H having a film thickness of substantially 20 to 50 μm can be obtained. of course,
The writing light 10 applied at this time is applied over the entire surface from the charge injection point to the charge discharge point. Further, at this time, the magnitude of the driving voltage divided into the photoconductor 2 depends not only on the distance from the charge injection point to the charge discharge point, but also on the thickness of the photoconductor 2. That is, as the thickness of the photoconductor 2 is reduced, the film resistance increases, and the switching of the charge over a correspondingly large voltage range can be performed. Furthermore, it goes without saying that even if a pinhole occurs in the photoconductor, it does not significantly affect optical switching. Therefore, the recording head of the present invention has an advantage that the recording head can be made inexpensive and have a high yield because the optical switching function can be easily obtained by using a photoconductor having a small film thickness. .

In addition, the flying of the ink is caused by the charge injection portion (FIG. 9).
This is because the electric charge injected into the ink from the point (C) shown in FIG. 3 is collected in the ink ejection portion 11 by the diffusion and the electric field, and the ink ejection portion 11 is attracted to the counter electrode 6 mainly by the action of the electric field. For this reason, by making the electric field concentrated and effectively acting, it is possible to facilitate the ink flying and to reduce the energy thereof. As shown in FIG. 8, the ink ejection portion 1 is located on a portion where the action of the electric field generated by applying a voltage to the source electrode 3 and the counter electrode 6 by the driving power supply 8 is large, that is, on the straight line.
By installing No. 1, it is easy to fly stable ink,
In addition, the applied voltage can be reduced.

Next, the case where OPC is used as the photoconductor 2 will be described. In this case, special care must be taken when using a stacked OPC in which the charge generation layer and the charge transport layer are separated from each other. In this case, referring to FIG. 8, it is preferable to form the charge generation layer only on the portion of the photoconductor 2 that is in contact with the source electrode 3. This is the same when the source electrode 3 is formed on the substrate side. This is because, in general, the conductivity of the charge generation layer of the OPC is relatively large even in the dark, so that when the charge generation layer is formed on the entire surface up to the ink chamber 5, the distance between the charge injection point and the charge discharge point is reduced. This is because it must be formed to exceed 100 μm, so that practical writing light energy irradiation cannot be performed.

If the photoconductor 2 is made of Bi ₁₂ SiO ₂₀ crystal (hereinafter abbreviated as BSO crystal) or the like, the above problem does not occur, and the photoconductor itself can be used as a substrate. However, the driving voltage to be used is extremely high and the material itself is expensive.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 shows a first configuration of a recording head according to the present invention.
It is explanatory drawing which shows an Example. 1 is a substrate, 2 is a photoconductor,
Reference numeral 3 denotes a source electrode, 4 denotes an insulating film, 5 denotes an ink chamber, 6 denotes a counter electrode, 7 denotes a light irradiation unit, 8 denotes a driving power source, 9 denotes a recording medium, 10 denotes a writing light, and 11 denotes an ink ejection unit. In FIG. 1, a high voltage is applied between the source electrode 3 and the counter electrode 6 by using the driving power supply 8, and writing is performed on the photoconductor 2 from the source electrode 3 side by using the light irradiation unit 7. Light 10 is irradiated. As a result, the resistance of the irradiation area of the photoconductor 2 decreases, and a photocurrent flows through the area. As a result, the source electrode 3 and the ink chamber 5 are energized, electric charges are injected into the ink chamber 5, and the ink flies from the ink ejection portion 11 toward the counter electrode 6 side under the Coulomb force. The recording medium 9 is attached and fixed.

In this embodiment, the photoconductor 2 and the source electrode 3
The insulating film 4 itself formed thereon forms an ink chamber 5 and has a structure in which ink is held by its surface tension. That is, the ink is supplied from an external ink supply means (not shown), and is transmitted through the ink chamber 5 by surface tension to fill the ink chamber 5. Although not clearly shown in FIG. 1, the ink chamber 5 is formed linearly in a direction perpendicular to the paper surface. This structure is characterized by an extremely simple structure, although the degree of filling of the ink in the ink chamber 5 changes depending on the holding posture of the recording head, and its flying characteristics are affected.

The insulating film 4 is formed as a thick film of about 10 to 50 μm. In the present example, a photoreactive acrylic resin was applied by spin coating, and then exposed and developed using an exposure mask corresponding to a predetermined shape pattern. Of course, as this insulating film 4, after printing another resin material, or forming an insulating material such as silicon dioxide or silicon nitride by a physical vapor deposition method such as vacuum evaporation or sputtering, and then using a resist, Needless to say, it can be formed into a predetermined shape.

As the photoconductor 2 of the present invention, a Se type, C
dS based, ZnO-based, BSO (Bi ₁₂ SiO ₂₀₎ photoconductive single crystal material inorganic photoconductors or i-type, such as, pi-type, p
Hydrogenated amorphous silicon such as in-type or CTL
A stacked organic photoconductor such as / CGL can be used. As the photoconductor 2, photoconductivity is important,
It is preferable that the potential difference of the surface potential due to light attenuation is large. The dark resistance of the inorganic photoconductor and the organic photoconductor is 10E.
The resistance is reduced to 10E8 to 10E11 Ω · cm by irradiating the photoconductor 2 with light, so that a photocurrent flows into the irradiation area. The thickness of the photoconductor 2 is 20 to
50 μm is preferable, and as the electrical characteristics, it is required that the resistance in a dark place is large, the sensitivity is high, and the photoresponsiveness is fast.

When amorphous silicon is used, the dark resistance is 10E9 to 10E11 Ω · cm.
The resistance value can be reduced to 4 to 10E6 Ω · cm, and a large surface potential difference can be secured. It goes without saying that the dark resistance increases as the thickness of the photoconductor decreases and as the distance from the charge injection point to the charge discharge point increases. In this embodiment, a-Si: H of 1 to 10 μm is used, but it is most preferable that the thickness be about 5 μm or less.

In order to increase the dark resistance and at the same time minimize the spread of electric charges in the direction of the film surface to realize a high-resolution ink leap, it is necessary to use an i-type hydrogen amorphous with an impurity element removed. It is preferable to use silicon. A semiconductor laser can be used as the light irradiating means 7 of the present invention, and the light irradiating means 7 irradiates the writing light 10 to a position corresponding to a desired image pixel on the photoconductor 2. On the photoconductor 2, the resistance decreases only in the irradiated desired image pixel region. Here, the light sensitivity can be improved by matching the oscillation wavelength of the laser light with the absorption coefficient of the photoconductor 2 for the oscillation wavelength to improve the optical attenuation rate of the photoconductor 2. The light irradiating means 7 optimizes the irradiation light intensity and the shape of the imaging light spot of the light irradiated from the semiconductor laser or the like by an optical lens or the like, and also forms an optical scanning mechanism including a polygon mirror or the like. can do. In the recording head of the present invention, since the laser light is emitted from the light irradiating means 7, an image can be formed on the photoconductor 2 at a position corresponding to a desired image pixel in a non-contact manner and at a high speed. In the present embodiment, a semiconductor laser is used as a light emitting source of the light irradiating means 7. However, the present invention is not limited to this.
e-Ne laser or semiconductor laser array or LED
An array, a halogen lamp, or the like can be sufficiently used as a light source. Needless to say, an optical shutter array or a liquid crystal television may be used instead of the optical scanning optical system.

In the present embodiment, the electric charge is injected into the ink by irradiating the photoconductor 2 with light. The amount of injection of the electric charge depends on the spot diameter of the laser light by the light irradiation means 7 and the irradiation light. It is determined by the intensity and the irradiation pulse width. The larger the laser spot diameter, the larger the irradiation area of the photoconductor 2 and the greater the injection amount. Further, by increasing the intensity of the irradiation light, the resistance value in the photoconductor 2 is greatly reduced, so that the photocurrent easily flows and the amount of the photocurrent injected into the ink also increases. This is the same when the irradiation pulse width is changed. In the recording head of the present invention, by controlling the amount of electric charge injected into the ink, the ink jump speed can be changed at a high speed according to the recording target.

As the source electrode 3 of the present invention, a metal thin film obtained by a general thin film forming process can be used. In this embodiment, an Al thin film having a thickness of 1 micron was used. In addition, any electrode material may be used as long as it is a conductive material.
Such as (Indium-Tin-Oxide) The ZnO or SnO ₂ or of these compounds or a conductive polymer material may be used. However, in the structure of the recording head of the present invention, although it functions as long as the resistance value of the source electrode 3 is smaller than the dark resistance of the photoconductor, a material having as low a resistance as possible is desired to obtain a stable operation. As the counter electrode 6 of the present invention, a material having good conductivity such as aluminum, copper, and gold can be used.

The power supply voltage applied between the source electrode 3 and the counter electrode 6 of the present invention was 1 kV to 4 kV.
This value varies depending on the conductivity, viscosity or surface tension of the ink filled in the ink chamber 5 and the material used for the photoconductor 2 or the film thickness or material of the insulating film 4. It is needless to say that the polarity of the driving power supply 8 is not affected in principle even if the polarity of the driving power supply 8 is reversed. However, since many inks are easily charged to the negative electrode, the opposite electrode 6 side is used as the positive electrode. Is preferred.

The physical properties of the ink of the present invention, which particularly affect the ink leap, include surface tension, viscosity, and electrical conductivity. For example, when the conductivity and the viscosity are considered to be constant, the maximum interval (hereinafter referred to as a maximum recording interval) of the ink jumped to the counter electrode has a surface tension of 20 to 50 dy.
In the range of n / cm, it increases as the surface tension decreases.
Therefore, as the surface tension is smaller, the resistance in the ink ejection process becomes smaller, and the ink can be ejected even with a weak electric field, so that the maximum recording interval can be increased. The surface tension is generally higher for water-based inks and 72.8 dyn for pure water.
/ Cm (20 ° C.), but the organic solvent is 20 dyn / c
m to 35 dyn / cm, it is desirable to use an ink in which a dye is dissolved in an organic solvent as the ink used in the present invention. It is also possible to dissolve an anionic surfactant, a cationic surfactant, a nonionic surfactant, or the like as a surfactant in the ink to reduce the surface tension and increase the maximum recording interval.

The viscosity of the ink solvent can be selected from a wide range. However, since the solvent having a low viscosity has high volatility, the storability of the ink is deteriorated, and the boiling point is 2 to ensure the storability.
Select a solvent in the range above 00 ° C. The relationship between the viscosity and the maximum recording interval is such that when the surface tension and the electrical conductivity are considered to be constant, the maximum recording interval increases as the viscosity decreases. Therefore, when the viscosity is low as in the case of the surface tension, the resistance in the ink ejection process is reduced, and the maximum recording interval can be increased.

In order for the ink to be ejected, it is necessary to inject electric charge from the photoconductor 2 into the ink and move the electric charge to the ink ejection port 11. Therefore, it is desirable that the electric conductivity is low. However, if the electric conductivity is too low, the electric charge injected into the ink before the electric charge reaches the tip of the ink meniscus formed in the ink ejection port 11 is charged in the ink. Is diffused, so that no ink ejection occurs. Therefore, the appropriate range of the ink conductivity of the present invention is desirably 2 × 10E-9 S / cm or less.

The above-mentioned ink characteristic setting values are as follows.
The light source conditions of the light irradiating means 7, the voltage value applied between the source electrode 3 and the counter electrode 6, the distance between the charge injection part to the photoconductor 2 and the charge discharge part to the ink chamber 5, the photoconductor 2
And the maximum inter-electrode distance, the thickness of the insulating film 4, etc., depend on whether or not the ink can fly.
It goes without saying that characteristic ranges such as viscosity and conductivity are not necessarily limited to the above values.

Further, by inserting the recording medium 9 between the counter electrode 6 and the ink ejection section 11 from a paper feeding means (not shown), the flying ink adheres to the recording medium 9. As a result, a desired print or image can be obtained on the recording medium 9. At this time, the dot size of the image pixel transferred onto the recording medium is determined by the distance between the recording medium 9 and the recording head, the voltage value applied between the source electrode 3 and the counter electrode 6, and the amount of the ink that has flown. Is determined by The amount of the flying ink can be controlled by the amount of writing light energy given from the light irradiation means 7 to the photoconductor 2. That is, dot modulation is possible. Regarding the distance between the recording medium 9 and the ink ejection section 11, if the distance is too short, there is a possibility that the recording medium 9 may come into contact with the ink due to a method of inserting the recording medium 9 or wrinkles thereof. Falls due to gravity, making it difficult to form image pixels at desired locations. Therefore, the distance between the recording medium 9 and the ink jetting portion 11 in this embodiment is preferably about 0.2 to 1 mm, and the desired distance is preferably about 0.5 mm.

As described above, by using the recording head shown in this embodiment, printing corresponding to dot-modulatable image pixels can be performed. (Embodiment 2) FIG. 2 shows a second embodiment of the recording head according to the present invention.
It is explanatory drawing which shows an Example, 13 is a wall. FIG.
In the figure, components having the same functions as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

The configuration of FIG. 2 differs from the configuration of FIG. 1 in that a wall 13 is provided on the photoconductive film 2 so that the ink chamber 5 is formed by the photoconductive film 2, the insulating film 4 and the wall 13. It is a point. With such a configuration, the ink state of the ink chamber 5 of the recording head of the present invention pointed out in the first embodiment is less affected by the posture position of the recording head.

In FIG. 2, as in the first embodiment, a state in which a high voltage is applied between the source electrode 3 and the counter electrode 6 by using the driving power supply 8 is applied. Is used to irradiate the photoconductor 2 with the writing light 10. At this time, the resistance of the irradiation area of the photoconductor 2 is reduced, and the source electrode 3 and the ink chamber 5 are energized. Electric charges are injected into the ink chamber 5, and the ink receives the Coulomb force, and the ink is ejected. It flies from the part 11 toward the counter electrode 6 and is attached and fixed to the recording medium 9.

The direction of ink jump is controlled by using the wall 13, the amount and speed of ink ejection with respect to the distance between the opposed electrodes 6 are stabilized, and the ink ejection is controlled by controlling the curve of the ink meniscus. The efficiency of concentration of electric charges in the vicinity of the portion 11 is increased, and energy for ink jump can be reduced. The width of the ink chamber 5 is preferably wide for ink introduction, but if it is too wide, there is no significant difference from the structure shown in FIG. In order to efficiently concentrate the electric charges in the ink ejection section 11, the narrower the better. The width of the ink chamber 5 differs depending on the structure and material of the ink and the ink chamber.
It is preferably about 0 to 200 μm.

When ink flows out from the wall 13, the ink jumps toward the counter electrode 6, and it is difficult to continue a desired image pixel. Therefore said wall 1
As the material of No. 3 or the state of the surface facing the counter electrode 6, it is necessary to have a large contact angle with ink and high insulation properties. However, since the contact angle is related to the ease of ink introduction into the ink chamber 5, simply increasing the contact angle is not sufficient. It is necessary to appropriately select the ink to be used (physical properties such as viscosity and surface tension) and the material and surface condition of the wall.

As described above, by using the present structure, the influence of the attitude position on the ink is reduced, and at the same time, the flying direction and conditions are stabilized, and the low energy of the flying condition is improved by improving the effect of concentrating the electric charges on the ink ejection section 11. And stabilization. As described above, the structure shown in FIG. 2 is a structure with a high cost merit because the above-described effect can be obtained with a small addition of the structure shown in FIG.

(Embodiment 3) FIG. 3 is an explanatory view showing an embodiment of a third configuration of the recording head according to the present invention, and 12 is a top plate. In FIG. 3, components having the same functions as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted. The configuration of FIG. 3 is different from the configuration of FIG. 1 in that a top plate 12 having a slit-shaped opening (hereinafter, referred to as a slit) corresponding to the ink ejection unit 11 is supported by a wall 13 and arranged. That is the point. With such a configuration, the ink state of the ink chamber 5 of the recording head of the present invention pointed out in the first and second embodiments becomes less affected by the posture position of the recording head, and at the same time, the ink ejection unit 11 The effect of concentrating charges on the substrate can be significantly improved.

In FIG. 3, as in the other embodiments, a state in which a high voltage is applied between the source electrode 3 and the counter electrode 6 by using the driving power source 8 and light irradiation means is applied from the source electrode 3 side. 7 is used to irradiate the photoconductor 2 with the writing light 10. At this time, the resistance of the irradiation area of the photoconductor 2 is reduced, and the source electrode 3 and the ink chamber 5 are energized. Electric charges are injected into the ink chamber 5, and the ink receives the Coulomb force, and the ink is ejected. It flies from the part 11 toward the counter electrode 6 and is attached and fixed to the recording medium 9.

The width of the slit provided on the top plate 12 determines the maximum value of the static ink pressure at the ink ejection section 11,
The ink that has received the static pressure forms a half-moon-shaped convex surface, that is, a meniscus, on the ink ejection portion 11, and determines the ink supply amount. Further, as the slit width is smaller, the curvature of the ink meniscus can be made smaller, and the Coulomb force for ejecting the ink can be made larger, so that the smaller the slit width, the better the recording characteristics. Therefore, the width of the slit provided on the top plate 12 is preferably about 50 to 100 μm which does not hinder the supply of the ink. Further, when ink flows out to the top plate 12,
The leaked ink flies toward the counter electrode 6 side, and it is difficult to continue a desired image pixel. Therefore, as the material of the top plate 12, it is necessary to use a material having a large contact angle with the ink used for the recording head of the present invention and a good insulating property. Therefore, as the top plate, a contact angle is secured by using a polyimide resin, a fluororesin, or the like, or treating the surface of the top plate made of an insulating material such as glass or ceramics with a silane coupling agent or the like. As a result, the above unstable phenomenon can be canceled if the static pressure of the ink is appropriate. Furthermore, the use of the top plate 12 controls the flight direction of the ink, stabilizes the amount and speed of ink ejection with respect to the distance between the ink ejection unit 11 and the counter electrode 6, and furthermore, changes the curve of the ink meniscus. By managing, the concentration efficiency of the ink is increased, and the energy required to fly the ink can be reduced.

(Embodiment 4) FIG. 4 is an explanatory view showing an embodiment of a fourth configuration of the recording head according to the present invention. In FIG. 4, components having the same functions as those in FIGS. 1, 2, and 3 are denoted by the same reference numerals, and description thereof is omitted. 4 differs from the configuration of FIG. 3 in the positional relationship between the photoconductor 2 and the source electrode 3 and the size of the photoconductor 2. Regarding the positional relationship, in the configuration of FIG. 3 (the same applies to FIGS. 1 and 2), the source electrode 3 is formed on the photoconductor 2, whereas in FIG.
Has the photoconductor 2 formed on the source electrode 3.
The recording head of the present invention can have such a configuration, and its structure can be changed by compatibility of the materials of the photoconductor 2 and the source electrode 3 in the manufacturing process. That is, the manufacturing process has a high degree of freedom, which is effective for improving productivity. Further, the size of the photoconductor 2 can be omitted because there is no necessity for the function except for the region that performs the optical switching function as the recording head. This is a necessary structure when using a high-cost material and the like, and is also an important structure in terms of limiting the functional area and increasing the flying position accuracy.

In FIG. 4, the function is the same as that of the other embodiments. A high voltage is applied between the source electrode 3 and the counter electrode 6 by using the driving power supply 8, and the source electrode 3 The light irradiation means 7 irradiates the photoconductor 2 with the writing light 10 from the side. At this time, the resistance of the irradiation area of the photoconductor 2 is reduced, and the source electrode 3 and the ink chamber 5 are energized. Electric charges are injected into the ink chamber 5, and the ink receives the Coulomb force, and the ink is ejected. It flies from the part 11 toward the counter electrode 6 and is attached and fixed to the recording medium 9.

(Embodiment 5) FIG. 5 is an explanatory view schematically showing one embodiment of the form of the photoconductor, source electrode and insulating film in the configuration of the recording head of the present invention. In FIG. 5, 2
Denotes a photoconductor, 3 denotes a source electrode, and 4 denotes an insulating film. still,
5 (a) and 5 (b), the photoconductor is formed only in the source electrode portion, that is, only in the region that functions by the writing light, but the present invention is not limited to this.

FIG. 5A shows a state in which the source electrode 3, the photoconductive film 2, and the insulating film 4 or the photoconductive film 2, the source electrode 3, and the insulating film 4 are formed on the substrate in this order. This is because, since the photoconductive film 2 is formed of a solid color, the charge discharging region is the entire long side end portion of the insulating film 4, and ink can be ejected from any location in principle. That is, in the configuration of the three portions of the photoconductive film, the source electrode, and the insulating film,
The resolution can be considered infinite. This is one feature of the recording head of the present invention.

FIG. 5B shows a state in which the photoconductive film 2 is divided while having the same form as FIG. 5A. With such a structure, the charge discharging region can be limited. In other words, this is effective when the resolution is to be finite or when the charge discharging area is to be limited for the spot of the writing light. As described above, if there is no functional problem and it is necessary, the photoconductor 2 can be processed into various shapes such as division.

(Embodiment 6) FIG. 6 is an explanatory view schematically showing another embodiment of the configuration of the photoconductor, source electrode and insulating film of the recording head according to the present invention, similarly to FIG. . FIG.
(A) has shown the whole image of this structure. This shows one embodiment of a configuration using a ladder-shaped electrode as a source electrode. As this configuration, a source electrode, a photoconductive film,
An insulating film or a photoconductive film, a source electrode, and an insulating film are formed in this order. The description of each of these components is given in FIG.
6B to 6D, FIG. 6B shows a source electrode, FIG. 6C shows a photoconductive film, and FIG. 6D shows an insulating film.

The charge discharging region, which is an element limiting the ink flying portion of the recording head, is a window portion formed in the insulating film, and is formed corresponding to the pitch of the ladder-like source electrode. For example, with this configuration,
It is possible to obtain effects such as defining the resolution and reducing interference between dots. As described above, if there is no functional problem and it is necessary, the shape of the insulating film can be changed.

(Embodiment 7) FIG. 7 is an explanatory view schematically showing several embodiments of the source electrode used in the configuration of the recording head of the present invention. FIG. 7A shows a comb-shaped electrode, and FIG.
7B shows a meandering electrode, FIG. 7C shows a ladder-like electrode provided with a float electrode, and FIG. 7D shows a state in which the float electrode and the ladder-like electrode are formed in different layers.

The charge injection is the most important function of the source electrode, and if it satisfies this, no matter what the shape of the source electrode, the basic problem is that the function of the recording head cannot be fulfilled. Absent. The shape of the source electrode is
It can be determined according to the shape problem of the recording head, the purpose of promoting the recording function (for example, controlling how the electric field is applied), and the like.

The float electrode is different from the function of the source electrode and serves to promote the charge discharging function, but it is also one of the applications of the present configuration, so that it is described here. (Embodiment 8) An embodiment of color printing using the recording head of the present invention will be described. Four line-shaped recording heads corresponding to the printing width of the recording medium are vertically stacked, and each recording head has yellow (Y), magenta (M), cyan (C), black (Bk ).

As a recording procedure, a high voltage is applied between a source electrode and a counter electrode by a power supply, and a yellow ink recording head is set at a printing position. Next, the photoconductor is irradiated with writing light from the source electrode side of the yellow ink recording head by a light irradiation means. At this time, the resistance of the irradiation area of the photoconductor is reduced, the source electrode and the ink chamber are in a state of being energized, electric charges are injected into the yellow ink chamber, and the yellow ink receives a Coulomb force and faces from the ink ejection section. It flies toward the electrode side and is attached and fixed to the recording medium. As a result, yellow ink of a desired image pixel is obtained in one line area of the recording medium.

Next, the recording head is moved, and the magenta ink recording head is set at the printing position. Then, magenta ink of a desired image pixel is obtained in one line area of the recording medium by the recording procedure. Next, move the recording head,
The cyan ink recording head is set at the printing position, and the same printing as described above is performed.

Finally, the recording head is moved, the black ink recording head is set at the printing position, and the same printing as described above is performed. After printing one line on the recording medium by the above procedure, the recording medium is moved by one line by the paper feeding means, and four recording heads are moved to return to the home position. By repeating this process, desired color image pixels for each image can be obtained on the recording medium.

In this embodiment, there are four types of ink configurations. However, by increasing the number of recording heads and supplying multicolor inks individually, full-color high-definition output printing and images with no restrictions on printing colors can be obtained. Will be. Furthermore, in the present embodiment, the method of driving the recording head of the present invention every time each color of YMCBk is transferred to the recording medium has been described. However, by providing a structure for simultaneously accessing each pixel information of YMCBk in the light irradiation means, It goes without saying that the recording pixel information of each color of YMCBk can be simultaneously irradiated on the photoconductor. In this embodiment, the line-shaped recording head has been described. However, since the recording head of the present invention can be used in a serial shape, the entire apparatus can be made compact.

(Embodiment 9) An embodiment of the fifth configuration using the recording head of the present invention will be described. The present embodiment has a configuration in which a recording head ejects multiple inks. For example, when color printing is used as a control, the recording head is formed with a source electrode, a photoconductor, and an insulating film corresponding to each divided into four on a substrate, and provided with ink chambers corresponding to each source electrode. . Then, yellow (Y), magenta (M), cyan (C), black (B
k) Ink is supplied.

As a recording procedure, a high voltage is applied between the individual source electrode and the counter electrode by a power supply, and the photoconductor is irradiated with writing light from the source electrode side of the yellow ink region by light irradiation means. I do. At this time, the resistance of the irradiation area of the photoconductor is reduced, the source electrode and the ink chamber are energized, electric charges are injected into the yellow ink chamber, and the yellow ink receives a Coulomb force and faces from the ink ejection section. It flies toward the electrode side and is attached and fixed to the recording medium. As a result, yellow ink of a desired image pixel is obtained in one line area of the recording medium. next,
Move the recording head and place the magenta ink recording head at the printing position. Then, magenta ink of a desired image pixel is obtained in one line area of the recording medium by the recording procedure.

Next, the recording head is moved, the cyan ink recording head is set at the printing position, and the same printing as described above is performed. Finally, the recording head is moved, the black ink recording head is set at the printing position, and the same printing as described above is performed. After printing one line on the recording medium by the above procedure, the recording medium is moved by one line by the paper feeding means, and the recording head is moved to return to the home position. By repeating this process, desired color image pixels for each image can be obtained on the recording medium.

In this embodiment, there are four types of ink configurations. However, by increasing the number of divisions of the recording head and supplying multicolor inks individually, full-color high-definition output printing and images can be obtained. . Further, when a type using a slit-shaped top plate is used as the recording head of the present invention, it goes without saying that four slits are formed in the top plate.

Although the present embodiment has been described with respect to a line-shaped recording head, the recording head of the present invention can be used in a serial shape, so that the entire apparatus can be made compact. The embodiments of the present invention have been described above.
It is needless to say that the operation of the recording head having this configuration is performed in the same manner for the opening of the top plate, even if it is a round hole often used in a conventional ink jet printer. By applying this embodiment or this embodiment, 1
Various recording heads such as a slit type, a multi-slit type, a slit-less type, a one-nozzle type, and a multi-nozzle type are possible.

[0060]

As described above, the recording head of the present invention has the following configuration. (1) At least a source electrode and a portion for supplying charges to ink are formed separated by a predetermined distance in the plane direction. (2) At least a source electrode and a portion where the charged ink is separated and fly are separated by a predetermined distance in the ink flying direction. (3) a substrate, a source electrode, a photoconductor, an ink supply path for supplying ink to the insulating film and the photoconductor, an ink chamber formed on the photoconductor, a counter electrode, and a counter electrode. An air layer having a predetermined layer thickness between the ink chamber and the ink chamber, a power supply for applying a voltage between the source electrode and the counter electrode, and a light irradiation unit for irradiating the photoconductor with light corresponding to a desired image pixel. At least. (4) The ink chamber is provided with an ink flying portion formed with a gap at a predetermined distance from the source electrode, and a portion irradiated with light corresponding to an image pixel is formed between the source electrode and the boundary between the photoconductor and the photoconductor. It is included in at least a part or the entirety of a predetermined gap provided between the ink chamber and the boundary. (5) A transparent substrate is used as the substrate, and the substrate is arranged so that light emitted from the light irradiating means is emitted from the transparent substrate side. (6) At least the gap between the ink and the source electrode is protected by an insulating film. (7) A part of the ink chamber is formed by a wall provided on a substrate, a photoconductor, a source electrode, or an insulating film. (8) A top plate having a slit hole formed corresponding to the ink flying portion is installed so as to sandwich the ink chamber between the top plate and the photoconductor. (9) The source electrode is formed linearly. (10) The source electrode is formed in a ladder shape. (11) The source electrode is formed in a comb shape. (12) The source electrode is formed in an irregular manner. (13) The photoconductor is divided and formed.

As a result, the following effects can be obtained. (1) Since the light is irradiated from the light irradiation means onto the photoconductor, the recording process is processed in a non-contact and high-speed manner. (2) By controlling the light energy of the light irradiating means, the amount of electric charge to be injected into the ink can make the ink jump speed high and can be varied for each recording medium object. (3) Basically, a nozzle for each image pixel is not required in the recording head, and high resolution, low cost, and cleaning after ink ejection can be easily performed by a slit configuration using a slit plate. (4) By providing a slit on the top plate, the direction of ink jump is controlled, the amount of ink ejected and the jump speed with respect to the distance between the opposing electrodes are stabilized, and the ink concentration efficiency is controlled by managing the curve of the ink meniscus. And the energy for the ink jump can be reduced. (5) Since the recording heads are vertically stacked, a plurality of recording units can be used. That is, there is no limitation on the printing color, and high-definition output printing in full color can be obtained. (6) Since the recording head is formed in a line shape, the printable range can correspond to the recording paper, the recording speed is greatly reduced, and high-speed printing can be performed. (7) Full-color high-definition output printing can be obtained by increasing the number of recording head divisions and supplying multicolor inks individually. (8) Since the recording head is formed in a serial shape, the recording head can be made compact. (9) Since the ink supply amount can be controlled by the photoconductor at the high speed of the continuity type, it can be performed with an apparatus configuration close to an on-demand type. (10) Since the resolution can be restricted by the spot diameter of the light supply means as compared with the ink jet method, the resolution can be as high as that of electrophotography. (11) Compared with the electrophotographic method, the apparatus configuration is simplified and the cost is low.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing one embodiment of a first configuration of a recording head according to the present invention.

FIG. 2 is an explanatory view schematically showing one embodiment of a second configuration of the recording head of the present invention.

FIG. 3 is an explanatory view schematically showing one embodiment of a third configuration of the recording head of the present invention.

FIG. 4 is an explanatory view schematically showing one embodiment of a fourth configuration of the recording head of the present invention.

FIG. 5 is an explanatory view schematically showing one embodiment of a form of a photoconductor, a source electrode, and an insulating film in the configuration of the recording head of the present invention. FIG. 5A shows a state in which the photoconductor is formed only near the source electrode. FIG. 5B shows a state in which the photoconductor is formed only near the source electrode and divided.

FIG. 6 is an explanatory view schematically showing one embodiment of the form of a photoconductor, a source electrode, and an insulating film in the configuration of the recording head according to the present invention. FIG. 6 (a) shows a configuration using a ladder-like electrode. In one embodiment, (b) is the ladder electrode used in (a) and (c) is
In the photoconductor used in (a), (d) is the insulating film used in (a).

FIGS. 7A and 7B are explanatory views schematically showing some examples of the source electrode used in the configuration of the recording head of the present invention, and FIG.
Is a comb-like electrode, (b) is a meandering electrode, (c) is a ladder-like electrode provided with a float electrode, and (d) is a state in which the float electrode and the ladder-like electrode are formed in different layers. .

FIG. 8 is an explanatory diagram schematically showing a basic configuration of the recording head of the present invention and the operation of each component.

FIG. 9 is an explanatory diagram supplementing FIG. 8;

FIG. 10 is an explanatory view schematically showing a configuration of a conventional electrostatic acceleration type ink jet recording apparatus in ink jet recording.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Photoconductor 3 Source electrode 4 Insulating film 5 Ink chamber 6 Counter electrode 7 Light irradiation means 8 Drive power supply 9 Recording medium 10 Writing light 11 Ink ejection part 12 Top plate 13 Wall 14 Electric field 1001 Ink recording head 1002 Counter electrode 1004 Optical signal irradiation means 1005 Recording paper 1010 Ink jetting part 1011 Substrate 1012 Upper plate 1014 Recording electrode 1015 Installation electrode 1016 Photoconductor 1018 Oil-based ink 1019 Document 1020 Selfoc lens

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Koji Kawaguchi 1-8-8 Nakase, Mihama-ku, Chiba-shi, Chiba Prefecture Inside Seiko Electronic Industry Co., Ltd. (72) Satoshi Ohama 1-8-1, Nakase, Mihama-ku, Chiba-shi, Chiba Within Seiko Electronic Industry Co., Ltd. (72) Inventor Seiji Kuwahara 1-8-1 Nakase, Mihama-ku, Chiba-shi, Chiba Inside SIID Rd. Center (72) Inventor Hiroshi Okano 1 Nakase, Mihama-ku, Chiba-shi, Chiba 8th Street Inside SII R.D. Center

Claims (13)

[Claims] 1. A charge is supplied to a predetermined ink portion by optically switching a photoconductor provided between a source electrode serving as a charge supply source and ink, and the ink portion supplied with the charge is provided. Wherein the source electrode and a portion for supplying electric charges to the ink are separated by a predetermined distance in a plane direction. 2. The ink jet recording apparatus according to claim 1, wherein at least the source electrode and a portion where the charged ink is separated and fly are separated by a predetermined distance in the ink flying direction. Recording head. 3. A substrate, a source electrode, a photoconductor, an insulating film and an ink supply path for supplying ink onto the photoconductor, an ink chamber formed on the photoconductor, and the ink. A counter electrode arranged at a predetermined distance from the chamber, a power supply for applying a voltage between the source electrode and the counter electrode, and a light irradiation unit for irradiating the photoconductor with light corresponding to a desired image pixel 3. The recording head according to claim 1, wherein the recording head has at least the following. 4. The ink chamber has an ink flying portion formed with a gap separated by a predetermined distance from the source electrode, and a light irradiation portion corresponding to the image pixel is formed by the source electrode. 4. The method according to claim 3, further comprising at least a part or all of a predetermined gap provided between the photoconductor and the boundary between the photoconductor and the boundary between the photoconductor and the ink chamber. Recording head. 5. The substrate according to claim 3, wherein the substrate is a transparent substrate, and the light irradiated from the light irradiating means is arranged to be irradiated from the transparent substrate side.
The recording head according to any one of the above. 6. The recording head according to claim 1, wherein at least a gap between the ink and the source electrode is protected by an insulating film. 7. The ink chamber according to claim 2, wherein a part of the ink chamber is formed by a wall formed on the substrate, the photoconductor, the source electrode, or the insulating film. Recording head. 8. A top plate having a slit hole formed corresponding to the ink flying portion, wherein the top plate is provided so as to sandwich the ink chamber between the top plate and the photoconductor. 8. The recording head according to any one of items 2 to 7. 9. The recording head according to claim 2, wherein the source electrode is formed in a straight line. 10. The recording head according to claim 2, wherein said source electrode is formed in a ladder shape. 11. The recording head according to claim 2, wherein said source electrode is formed in a comb shape. 12. The recording head according to claim 2, wherein said source electrode is formed in an irregular manner. 13. The recording head according to claim 2, wherein said photoconductor is formed in a divided manner.