JP2001191534A - Recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable recorder capable of preventing arrival positions of ink drops from being shifted, of performing high quality printing by achieving uniform dots and of corresponding to paper sheets having various thicknesses. SOLUTION: This recorder comprises an image carrier body 11 on which an electrostatic latent image is formed, an electrode housing section 13 having an aperture section 12 provided in close proximity to and in opposition to the electrostatic latent image forming face, a plurality of ink ejection electrodes 14 provided in such a manner that a part of each electrode 14 is dripped in the ink held in the electrode housing section 13 and the tip thereof is projected from the aperture section 12 and an electric field forming means 16 for applying a predetermined voltage across the image carrier body 11 and the plurality of ink ejection electrodes 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recording apparatus for recording and printing images such as characters and graphics by discharging ink onto a recording medium.

[0002]

2. Description of the Related Art In recent years, a recording apparatus (printing apparatus) using ink represented by an ink-jet printer has tended to have high image quality and high speed, and has been particularly noted as a color output apparatus which can be reduced in price. .

First, the principle of operation of a conventional recording apparatus will be described.

FIG. 9A is a front sectional view of a conventional recording apparatus, and FIG. 9B is a plan sectional view of the same. FIG.
10A is a front sectional view of a head portion of a conventional recording apparatus, and FIG. 10B is a plan sectional view thereof.

The conventional recording apparatus includes an ink 1 in which a pigment is dispersed in an insulating liquid, an ink discharge electrode 2, a sub tank 3 holding the ink 1 and having an opening, and an ink tank 4 for supplying ink to the sub tank 3. A driver 5 for applying a voltage to the ink ejection electrode 2 in accordance with a print signal; a platen 6 for holding and feeding the recording paper 5a;
And a paper feed roller 8 for applying a potential to the paper.

Next, the operation of the recording apparatus having the above configuration will be described.

The ink 1 is supplied from the ink tank 4 to the sub-tank 3 and is filled with ink up to the opening. The platen 6 is supplied with a potential of −3 kV by the power supply 7. The gap between the tip of the ink discharge electrode 2 and the opening is 300 μm.

By applying a pulse voltage of 300 V according to a print signal from the driver 5 to the electrode 2 for ink ejection,
Forming an electric field between the platen 6 and the ink discharge electrode 2;
The ink at the tip of the ink discharge electrode 2 receives electrostatic force and flies in the direction of the platen to discharge an ink droplet 9. The ink droplets 9 land on the recording paper 5a, and thereafter, the platen 6 moves by a pitch corresponding to the resolution, and the next line is printed. By repeating this line feed and printing, characters and graphics are created on the recording paper 5a.

[0009]

However, the above conventional recording apparatus has the following problems. (1) As shown in FIGS. 10A and 10B, the shape of the ink meniscus formed at the tip of the ink discharge electrode 2 becomes non-uniform, and the ink droplets may be misaligned when the ink is discharged. And the dot diameter to be printed varies. (2) Since ink having a high dielectric constant or a member having an opening is interposed around the tip of the ink discharge electrode 2, the electric field intensity in the vicinity of the ink discharge electrode 2 involved in discharge decreases or becomes non-uniform. In other words, there has been a problem that uniform ejection of ink is hindered and printing defects occur. (3) If the mounting parallelism between the ink discharge electrode 2 and the platen 6 deviates during the assembly of the apparatus, a landing deviation and a dot diameter variation occur, and the printing quality tends to deteriorate. (4) Since the distance between the platen 6 and the opening of the sub-tank 3 is small, when a plurality of recording papers are erroneously fed, the sub-tank 3 may be damaged due to contact, or printing may not be performed if the recording paper is thick. There was a point.

[0010] The present invention solves the above-mentioned problems of the prior art. It is possible to perform high-quality printing with little deviation of landing of ink droplets, high dot uniformity, and paper of various thicknesses. It is an object of the present invention to provide a highly reliable recording device that can perform the recording.

[0011]

In order to solve the above-mentioned problems, the present invention comprises an ink discharge electrode projecting from an opening of an ink storage means, and an image carrier disposed at a portion opposite to the electrode. is there.

[0012] This makes it possible to stabilize the ink meniscus at the tip of the ink discharge electrode, to improve the discharge failure due to the variation in the installation accuracy during assembly, and to prevent the ink droplet from being displaced when discharging the ink droplet. In addition, a highly reliable recording apparatus that has high dot uniformity, excellent printing quality, and can handle paper of various thicknesses can be obtained.

[0013]

According to a first aspect of the present invention, there is provided a recording apparatus comprising: an image carrier on which an electrostatic latent image is formed; and an opening provided to face the electrostatic latent image forming surface of the image carrier. Having an electrode housing portion, a plurality of ink ejection electrodes partially immersed in ink held in the electrode housing portion, and having a tip protruding from the opening, an image carrier, and an ink ejection electrode Electric field forming means for applying a predetermined voltage therebetween.

Accordingly, the following operation is provided. (A) Since the tip of the ink discharge electrode protrudes from the opening of the electrode accommodating portion, the tip of the ink discharge electrode can prevent interference due to electrostatic force or the like from the opening, and as a result, the ink to be discharged can be prevented. It is possible to perform printing with high dot uniformity with no landing deviation of droplets. (B) Since the tip of the ink discharge electrode is projected,
By reducing the radius of the ink meniscus at the tip,
It is possible to stably maintain the ink meniscus formed by increasing the static pressure at the meniscus and perform printing with excellent print quality. (C) Since an electric field forming means for applying a predetermined voltage between the image carrier and the ink discharging electrode is provided, the voltage is appropriately adjusted to the most preferable value, and the voltage is adjusted to correspond to various thicknesses of paper. Highly reliable printing can be performed.

According to a second aspect of the present invention, in the first aspect, the ink discharging electrode is supported by the substrate disposed in the electrode housing, and the tip of the ink discharging electrode projects from the end of the substrate. It is provided.

Thus, the following operation is obtained in addition to the operation of the first aspect. (A) Since the tip of the ink discharge electrode is provided so as to protrude from the end of the substrate, the electric field strength of the ink meniscus at the tip of the ink discharge electrode can be increased, and the ink discharge electrode and the image carrier can be used. Can be widened, and printing on paper having different thicknesses can be easily performed. (B) Since the tip of the ink discharge electrode is provided so as to protrude from the end of the substrate, the electric field strength of the ink meniscus at the tip of the ink discharge electrode can be increased, and the voltage supplied to the ink discharge electrode can be increased. Can be reduced, and the price of the device can be reduced.

According to a third aspect of the present invention, in the recording apparatus according to the first or second aspect, the tips of the plurality of ink discharge electrodes are arranged along the lateral direction of the image carrier, and the total arrangement width of the tips is determined by the image. The width is set to be longer than the width of the carrying area of the electrostatic latent image formed on the carrying body.

Thus, the following operation can be obtained in addition to the operation of the first or second aspect. (A) Since the dummy ink ejection electrodes are arranged in a wider area than the electrostatic latent image holding area where the actual printing is performed on the image carrier, the holding area and the ink ejection electrode arrangement area are different. The lines of electric force do not spread to the end side at the end of the printing area as in the case of matching, and the state of the lines of electric force is uniform at the end as well as the middle part And printing with high dot uniformity can be performed. (B) Since the tip of the ink discharge electrode is arranged along the side line direction of the image carrier, the rotation of the image carrier causes
Printing corresponding to the electrostatic latent image can be efficiently performed. (C) Since the ink discharge electrodes serving as dummy are arranged in a wider area than the holding area of the electrostatic latent image on which the actual printing is performed on the image carrier, the ink discharge electrodes and the image support required at the time of assembly are provided. At the time of alignment adjustment in the direction of the body side line, a rough adjustment step of installing the ink discharge electrode is not required, and assemblability can be improved.

According to a fourth aspect of the present invention, in the recording apparatus according to any one of the first to third aspects, at least one set of a plurality of ink discharging electrodes is electrically connected to each other, and each potential is set to an electric field forming means. , And are controlled equally.

Thus, the following operation can be obtained in addition to the operation of any one of the first to third aspects. (A) By applying a trigger pulse to the ink ejection electrode facing the image carrier using a common driver device or the like, a recording device with no landing displacement and excellent print quality can be obtained. (B) When all of the plurality of ink discharge electrodes are electrically connected to each other, the entire voltage control can be uniformly performed using a simple control mechanism. (C) Since the electric system is simple, it is possible to manufacture a low-priced recording apparatus with few failures and easy maintenance. (D) When at least one set of a plurality of ink ejection electrodes is electrically connected to each other, the load on the driver device can be reduced by reducing the number of ink ejection electrodes that one driver device handles, It is possible to form a stable electric field with little load fluctuation, and it is possible to obtain better printing quality.

According to a fifth aspect of the present invention, in the recording apparatus according to any one of the first to fourth aspects, each of the ink ejection electrodes is synchronized with an image signal of an electrostatic latent image formed on the image carrier. It is configured to have a driver for controlling the potential.

Thus, the following operation can be obtained in addition to the operation of any one of the first to fourth aspects. (A) By connecting a driver to each of the ink ejection electrodes facing the image carrier, the ink ejection electrodes are individually controlled, so that excellent print quality capable of area gradation can be obtained. (B) Since each of the ink discharging electrodes is controlled to a potential synchronized with the image signal of the electrostatic latent image, it is possible to reliably discharge an appropriate amount of ink droplets to the electrostatic latent image on the image carrier. Thus, it is possible to provide a recording apparatus having excellent gradation properties. (C) Since a potential synchronized with the image signal of the electrostatic latent image is added to each of the ink ejection electrodes, precise and diverse printing can be performed as compared with a case where the entire potential is uniformly controlled. .

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(Embodiment 1) FIG. 1 (a) is a front view of a recording apparatus according to Embodiment 1, FIG. 1 (b) is a plan view of the same, and FIG. FIG. 2B is a detailed front view of a print head unit of the recording apparatus in FIG. 2, and FIG. 2B is a detailed plan view thereof.

1 and 2, reference numeral 10 denotes a first embodiment.
Recording device 11 is an image carrier on which an electrostatic latent image is formed, 1
Reference numeral 2 denotes an opening provided to face the electrostatic latent image forming surface of the image carrier 11, reference numeral 13 denotes a sub-tank (electrode accommodating portion) having an opening 12 and having ink therein, and reference numeral 14 denotes a sub-tank 1
A plurality of ink ejection electrodes, some of which are immersed in the ink inside 3 and whose tips project from the opening 12;
Reference numeral 15 denotes a substrate for supporting the ink discharge electrode 14, and 1
Reference numeral 6 denotes an electric field forming means for applying a predetermined voltage between the image carrier 11 and the ink discharge electrode 14, and 17 denotes a sub tank 1
3 is an ink tank for supplying ink, 18 is a laser scan unit (LSU) for irradiating the image carrier 11 with laser light to form an electrostatic latent image, and 19 is charging the surface of the image carrier 11 Charger for charging, 2
Reference numeral 0 denotes a static elimination lamp for removing residual charges on the image carrier 11, 21 denotes a recording paper on which an image corresponding to an electrostatic latent image formed on the image carrier 11 is printed, and 22 denotes a recording paper of the image carrier 11. The inside conductive substrate, 23 is a photoconductor covered and formed on the conductive substrate 22, and 24 is a latent image portion formed on the photoconductor 23.

The ink used in the recording apparatus 10 is dispersed by adding positively charged carbon black as a pigment, metal soap as a charge control agent, resin, etc. to Isopar, a saturated hydrocarbon solvent having electrical insulation. The ζ potential is 80 mV and the specific resistance is 8 × 10 ⁸ Ω
cm, the surface tension is 24 mN / m, and the viscosity is 5 mPa · s.

The ink ejection electrodes 14 are formed on a polyimide substrate having a thickness of 75 μm and have a wiring pitch of 150 dpi and a number of electrodes of 3
Two flexible boards (FP) with nickel plating and gold plating on copper wiring with a line width of 70 μm and a copper thickness of 25 μm
C) was used.

The substrate 15 can be formed of ceramics, plastic, or the like, and can be formed by combining these.

The sub-tank 13 is made of transparent polycarbonate and has a height of 300 μm, a width of 8 mm, and a height of an opening 12 provided opposite the image carrier 11.
The ink is supplied via the.

The image carrier 11 is a rotating body also called a photosensitive drum, and is formed by covering a conductive substrate 22 with a surface layer made of a photoconductor 23 thereon. A laser scan unit (LSU: Laser Scan U) is provided on the photoconductor 23 on the surface of the photosensitive drum 11.
(nit) 18 to irradiate a laser beam corresponding to the print signal to write an electrostatic latent image.

The electric field forming means 16 includes the ink discharging electrode 1.
It is configured to apply a potential of 300 V between the image carrier 4 and the image carrier 11.

The pressure difference between the sub tank 13 and the ink tank 17 is -50 Pa, and the opening 12 of the ink discharge electrode 14 is
Is 300 μm, and the gap between the photosensitive drum 11 and the tip of the ink discharge electrode 14 is 1 mm.

The operation of the recording apparatus 10 having the above configuration will be described below. The photoconductor 23 on the surface of the photoconductor drum 11 is charged at a surface potential of 1 kV by the charging charger 19, while the conductive substrate 22 on the back surface of the photoconductor 23 is charged.
Indicates -1 kV. The LSU 18 forms an electrostatic latent image by scanning in the main scanning direction of the photosensitive drum 11 while oscillating laser light in response to a print signal. As a result, the surface potential of the latent image portion 24 drops to about 100V.

When a one-line latent image is formed, the photosensitive drum 11 rotates in the counterclockwise direction by the print resolution pitch in the sub-scanning direction.

As shown in FIG. 1B, the ink discharge electrodes 14 are formed so as to correspond to the maximum number of pixels and the pitch (resolution) in the main scanning direction formed on the photosensitive drum 11, Each of the discharge electrodes 14 is electrically connected to each other.
300V is provided.

Next, the photosensitive drum 11 on which the latent image portion 24 has been formed rotates counterclockwise, and is inserted into a position which is in close proximity to the ink discharge electrode 14 as shown in FIGS. 2 (a) and 2 (b). When applied, a potential difference of 1.2 kV is generated between the ink discharging electrode 14 and the conductive substrate 22 in the photosensitive drum 11, the electric field intensity becomes highest, and the ink at the tip of the electrode from the ink discharging electrode 14 is charged. And a positive charge, a Coulomb force is generated between the negatively charged latent image portion 24 side, the meniscus is torn off, the ink droplet 9 flies, and lands on the recording paper 21 to perform printing. Done.

Further, the photosensitive drum 11 is provided with a discharging lamp 20.
Removes electricity from the surface.

Again, the surface of the photosensitive drum 11 is charged by the charger 19. Hereinafter, the above operation is repeated.

Next, the Coulomb force and the static ink pressure acting on the ink meniscus will be described. The pressure P based on the Coulomb force acting on the ink meniscus is represented by the following equation, where E is the electric field strength and dielectric constant ε of the ink.

[0040] it is necessary to increase the electric field strength in order to increase the P = (1/2) εE ² Coulomb force acting on the ink meniscus from the above equation.

Assuming that the electric field strength E is r, the radius of the ink meniscus is d, the distance from the ink meniscus to the surface of the photosensitive drum 11 is d, and the potential difference is V, E = (1/2). ((1 / r) + (1 / (r + d)))
V / log ((r + d) / r)) where the electric field strength indicates that the electric field strength increases as the curvature r of the meniscus decreases.

Further, it shows the stability of the ink meniscus.
The ink static pressure h that can be held by the ink meniscus is represented by h = 2T / (ρgr), where r is the ink density ρ, gravitational acceleration g, ink surface tension T, and ink meniscus radius of curvature. It can be seen that the smaller the radius of curvature r of the ink meniscus, the more the ink meniscus can be stabilized.

As shown in FIG. 2A, the ink discharge electrode 14 protrudes from the opening 12 of the sub-tank 13, so that the ink discharge electrode 14, the substrate 15, and the sub-tank 1
The radius of curvature of the ink meniscus portion formed by the third opening 12 and the ink meniscus can be made smaller than before, and the Coulomb force acting on the ink can be increased without reducing the distance from the ink meniscus to the surface of the photosensitive drum 11. . Further, the meniscus shape is stabilized by reducing the radius of curvature of the ink meniscus. Further, each of the ink ejection electrodes corresponds to one pixel of the latent image. As described above, it is possible to form a high-quality image with little dot diameter variation and landing deviation. Further, since each ink discharge electrode and one latent image pixel correspond to each other, the photosensitive drum 11 and the ink discharge electrode
Image quality hardly deteriorates even if the relative position of
A high-precision adjustment mechanism is not required, the productivity of the apparatus can be increased, and an expensive driver is not required, so that a low-priced recording apparatus can be provided.

In this embodiment, the ink used was a saturated hydrocarbon solvent, but the specific resistance of the ink was 1 × 10 ⁶ to 1 × 10 ^6.
If the resistivity is within ¹² Ωcm, good printing performance is exhibited, so that an aqueous ink can be used as long as the resistivity is within the above-mentioned range.

(Embodiment 2) FIG. 3 (a) is a detailed front view of a print head portion of a recording apparatus according to Embodiment 2, and FIG. 3 (b) is a detailed plan view thereof.

In FIG. 3, reference numeral 30 denotes a subtank in the printing apparatus according to the second embodiment, 31 denotes an ink discharge electrode arranged in the subtank 30, and 32 denotes an ink discharge electrode 3.
1 is a substrate for supporting the substrate 1 at a predetermined position. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in the drawing, the recording apparatus according to the second embodiment uses an ink discharge electrode 31 formed on a substrate 32.
Are projected from the substrate 32. This is due to tape auto-mounting bonding (TAB: TAPE A).
UTMATED BONDING) manufacturing technology. Otherwise, the configuration is the same as that of the first embodiment.

In the recording apparatus having the above configuration, FIG.
As shown in (a) and (b), the ink discharge electrode 31 protrudes from the openings of the substrate 32 and the sub tank 30. Thereby, the radius of curvature of the ink meniscus can be reduced, and the ink meniscus is further stabilized,
Since the Coulomb force required for ink flying can be increased, the distance between the photosensitive drum 11 and the ink discharging electrode 31 can be increased, and reliability can be improved.
In addition, the amount of ink that is not involved in ejection can be further reduced in the electric field portion acting between the ink ejection electrode 31 and the photosensitive drum 11, and a high-quality image with less dot diameter variation and landing deviation can be formed.

(Embodiment 3) FIG. 4 is a detailed front view of a print head section of a recording apparatus according to Embodiment 3.

In FIG. 4, reference numeral 40 denotes a sub-tank in the printing apparatus of the third embodiment, 41 denotes an ink discharging electrode disposed in the sub-tank 40, and 42 denotes an ink discharging electrode 4.
1 is a substrate for supporting the substrate 1 at a predetermined position. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in the drawing, the recording apparatus according to the third embodiment includes an ink discharge electrode 41 formed on a substrate 42.
Are processed into a sharper shape, with the tip end of which protrudes from the substrate 42. This is similar to the method of forming the ink discharge electrode in the second embodiment, and after manufacturing the ink discharge electrode 41 protruding from the substrate 42 by the TAB manufacturing technique,
It can be manufactured by polishing the tip by electric field polishing.
Otherwise, the configuration is the same as that of the first embodiment.

In the recording apparatus having the above configuration, as shown in FIG. 4, the ink discharge electrode 41 protrudes from the openings of the substrate 42 and the sub tank 40, and the radius of curvature of the ink meniscus can be further reduced. Because the Coulomb force required for further stabilization and ink flying can be increased, the distance between the photosensitive drum 11 and the tip of the ink discharge electrode 41 can be increased, so that reliability can be improved. The amount of ink that is not involved in the ejection in the electric field portion acting between the ink ejection electrode 41 and the photosensitive drum 11 can be further reduced. Further, since the tip of the ink discharge electrode 41 is sharp, only one portion having the maximum electric field intensity is provided, so that the ink discharge can be further stabilized. As described above, it is possible to form a high-quality image with less dot diameter variation and landing deviation.

(Embodiment 4) FIG. 5 is a detailed front view of a print head section of a recording apparatus according to Embodiment 4.

In FIG. 5, reference numeral 50 denotes a sub-tank in the recording apparatus of the fourth embodiment, 51 denotes an ink discharge electrode disposed in the sub-tank 50, and 52 denotes a dummy electrode disposed on the end side of the opening of the sub-tank 50. Reference numerals 53 denote substrates for supporting the ink discharge electrodes 51 and the dummy electrodes 52 at predetermined positions. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in the drawing, the recording apparatus according to the fourth embodiment uses an ink ejection electrode 51 formed on a substrate 53.
The dummy electrodes 52 which are not involved in printing are provided at both ends (only one side is shown in FIG. 5) at both ends of the number of pixels formed on the photosensitive drum 11 in the main scanning direction. Otherwise, the configuration is the same as that of the first embodiment.

By providing the dummy electrodes 52 at both ends of the ink discharge electrode 51, the ink meniscus of the ink discharge electrodes 51 at both ends can be formed to have substantially the same shape as other ink discharge electrodes. Therefore, it is possible to form a high-quality image with less landing deviation due to uneven meniscus shape at the time of printing ink discharge electrodes at both ends.

(Embodiment 5) FIG. 6 (a) is a detailed front view of a print head section of a recording apparatus according to Embodiment 5, and FIG. 6 (b) is a detailed plan view thereof.

In FIG. 6, reference numeral 60 denotes a sub-tank in the printing apparatus of the fifth embodiment, 61 denotes an ink discharge electrode disposed in the sub-tank 60, and 62 denotes an ink discharge electrode 6.
Reference numeral 63 denotes a driver for supplying a voltage corresponding to a print signal to the ink discharge electrode 61. In the following, the first embodiment will be described.
The same components as those described above are denoted by the same reference numerals, and description thereof is omitted.

As shown in the figure, the plurality of ink discharge electrodes 61 are electrically connected to each other, and further connected to a driver 63 for supplying a voltage according to a print signal. Otherwise, the configuration is the same as that of the first embodiment.

A driver 63 is connected to the ink discharge electrode 61, and when the photosensitive drum 11 and the ink discharge electrode 61 approach each other, the driver 63 is activated by a print signal to operate the respective ink discharge electrodes 61. Up to 30
By applying a voltage having a trigger waveform having a voltage of 0 V and a pulse width of 100 μs, variation in the flight timing between the respective ink discharge electrodes is improved, and high-quality image formation with less landing deviation can be achieved.

(Embodiment 6) FIG. 7A is a detailed front view of a print head portion of a recording apparatus according to Embodiment 6, and FIG. 7B is a detailed plan view thereof.

In FIG. 7, reference numeral 70 denotes a sub-tank in the printing apparatus according to the sixth embodiment, 71 denotes an ink discharge electrode disposed in the sub-tank 70, and 72 denotes an ink discharge electrode 7.
Reference numeral 73 denotes a driver for supplying a voltage corresponding to a print signal to the ink discharge electrode 71. In the following, the first embodiment will be described.
The same components as those described above are denoted by the same reference numerals, and description thereof is omitted.

As shown in the figure, a driver 73 for supplying a voltage having a desired pulse width according to a print signal is connected to the ink discharge electrode 71. Further, as shown in FIG. 7B, the latent image portions 74 to 76 formed on the photosensitive drum 11 by the LSU 18 have different pixel areas, so that an area gray scale image can be obtained. Otherwise, Embodiment 1
This is the same configuration as.

A driver 73 is connected to each of the ink ejection electrodes 71. When the photosensitive drum 11 and the ink ejection electrode 71 approach each other, the driver 73 is connected.
Latent image portions 74 to 76 more facing the ink ejection electrode 71
By applying a potential of a pulse width corresponding to the area, the area gradation can be performed, and a high-quality image can be formed.

(Embodiment 7) FIG. 8 is a configuration diagram of a recording apparatus according to Embodiment 7.

In FIG. 8, reference numeral 80 denotes a recording apparatus according to the seventh embodiment; 81, a transfer drum for transferring an electrostatic latent image on the image carrier 11 onto recording paper 21; Is a pressure roller for pressing the recording paper 21, and 84 is a power supply for applying a predetermined voltage to the transfer drum 81. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in the figure, the steps of charging the photosensitive drum 11, latent image, and erasing are the same as those in the first embodiment.
The ink is landed directly on the photosensitive drum 11 and the power supply 8
The transfer to the recording paper 21 is performed by the transfer drum 81 to which the bias potential of -500 V is applied by the step 4. Next, fixing is performed by the heat roller 82 and the pressure roller 83.

In the present embodiment, since the ink is landed on the photosensitive drum 11 once, good print quality can be obtained with little dependence on the paper thickness and the material of the recording paper 21. Depending on the ink, a sufficient fixing strength can be obtained without the fixing step.

[0069]

According to the present invention, the following effects can be obtained.

According to the recording apparatus of the first aspect, the following effects can be obtained. (A) Since the tip of the ink discharge electrode protrudes from the opening of the electrode accommodating portion, the tip of the ink discharge electrode can prevent interference due to electrostatic force or the like from the opening, and as a result, the ink to be discharged can be prevented. It is possible to perform printing with high dot uniformity with no landing deviation of droplets. (B) Since the tip of the ink discharge electrode is projected,
By reducing the radius of the ink meniscus at the tip,
It is possible to stably maintain the ink meniscus formed by increasing the static pressure at the meniscus and perform printing with excellent print quality. (C) Since an electric field forming means for applying a predetermined voltage between the image carrier and the ink discharging electrode is provided, the voltage is appropriately adjusted to the most preferable value, and the voltage is adjusted to correspond to various thicknesses of paper. Highly reliable printing can be performed.

According to the recording apparatus of the second aspect, the following effects can be obtained in addition to the effects of the first aspect. (A) Since the tip of the ink discharge electrode is provided so as to protrude from the end of the substrate, the electric field strength of the ink meniscus at the tip of the ink discharge electrode can be increased, and the ink discharge electrode and the image carrier can be used. Can be widened, and printing on paper having different thicknesses can be easily performed. (B) Since the tip of the ink discharge electrode is provided so as to protrude from the end of the substrate, the electric field strength of the ink meniscus at the tip of the ink discharge electrode can be increased, and the voltage supplied to the ink discharge electrode can be increased. Can be reduced, and the price of the device can be reduced.

According to the recording apparatus of the third aspect, the following effects can be obtained in addition to the effects of the first or second aspect. (A) Since the dummy ink ejection electrodes are arranged in a wider area than the electrostatic latent image holding area where the actual printing is performed on the image carrier, the holding area and the ink ejection electrode arrangement area are different. The lines of electric force do not spread to the end side at the end of the printing area as in the case of matching, and the state of the lines of electric force is uniform at the end as well as the middle part And printing with high dot uniformity can be performed. (B) Since the tip of the ink discharge electrode is arranged along the side line direction of the image carrier, the rotation of the image carrier causes
Printing corresponding to the electrostatic latent image can be efficiently performed. (C) Since the ink discharge electrodes serving as dummy are arranged in a wider area than the holding area of the electrostatic latent image on which the actual printing is performed on the image carrier, the ink discharge electrodes and the image support required at the time of assembly are provided. At the time of alignment adjustment in the direction of the body side line, a rough adjustment step of installing the ink discharge electrode is not required, and assemblability can be improved.

According to the recording apparatus of the fourth aspect, in addition to the effect of any one of the first to third aspects,
The following effects can be obtained. (A) By applying a trigger pulse to the ink ejection electrode facing the image carrier using a common driver device or the like, a recording device with no landing displacement and excellent print quality can be obtained. (B) When all of the plurality of ink discharge electrodes are electrically connected to each other, the entire voltage control can be uniformly performed using a simple control mechanism. (C) Since the electric system is simple, it is possible to manufacture a low-priced recording apparatus with few failures and easy maintenance. (D) When at least one set of a plurality of ink ejection electrodes is electrically connected to each other, the load on the driver device can be reduced by reducing the number of ink ejection electrodes that one driver device handles, It is possible to form a stable electric field with little load fluctuation, and it is possible to obtain better printing quality.

According to the recording apparatus of the fifth aspect, in addition to the effect of any one of the first to fourth aspects,
The following effects can be obtained. (A) By connecting a driver to each of the ink ejection electrodes facing the image carrier, the ink ejection electrodes are individually controlled, so that excellent print quality capable of area gradation can be obtained. (B) Since each of the ink discharging electrodes is controlled to a potential synchronized with the image signal of the electrostatic latent image, it is possible to reliably discharge an appropriate amount of ink droplets to the electrostatic latent image on the image carrier. Thus, it is possible to provide a recording apparatus having excellent gradation properties. (C) Since a potential synchronized with the image signal of the electrostatic latent image is added to each of the ink ejection electrodes, precise and diverse printing can be performed as compared with a case where the entire potential is uniformly controlled. .

[Brief description of the drawings]

FIG. 1A is a front view of a recording apparatus according to a first embodiment; FIG.

FIG. 2A is a detailed front view of a print head unit of the recording apparatus according to the first embodiment; FIG.

FIG. 3A is a detailed front view of a print head unit of the recording apparatus according to the second embodiment, and FIG.

FIG. 4 is a detailed front view of a print head unit of the recording apparatus according to the third embodiment.

FIG. 5 is a detailed front view of a print head unit of a recording apparatus according to a fourth embodiment.

6A is a detailed front view of a print head unit of a recording apparatus according to Embodiment 5, and FIG.

7A is a detailed front view of a print head unit of a recording apparatus according to Embodiment 6, and FIG.

FIG. 8 is a configuration diagram of a recording apparatus according to a seventh embodiment.

9A is a front sectional view of a conventional recording apparatus. FIG. 9B is a plan sectional view of a conventional recording apparatus.

10A is a detailed front view of a head section of a conventional recording apparatus. FIG. 10B is a detailed plan view of a head section of a conventional recording apparatus.

DESCRIPTION OF SYMBOLS 10 Recording device 11 Photoreceptor drum (image carrier) 12 Opening 13 Subtank (electrode accommodating part) 14 Ink ejection electrode 15 Substrate 16 Electric field forming means 17 Ink tank 18 Laser scan unit (LSU) 19 Charging Charger 20 Static elimination lamp 21 Recording paper 22 Conductive substrate 23 Photoconductor 24 Latent image section 30 Subtank (electrode accommodation section) 31 Ink ejection electrode 32 Substrate 40 Subtank (electrode accommodation section) 41 Ink ejection electrode 42 Substrate 50 Subtank ( Electrode accommodation part) 51 Ink ejection electrode 52 Dummy electrode 53 Substrate 60 Sub tank (electrode accommodation part) 61 Ink ejection electrode 62 Substrate 63 Driver 70 Sub tank (electrode accommodation part) 71 Ink ejection electrode 72 Substrate 73 Driver 74 Latent image part 75 Latent image part 76 Latent image part 8 0 Recording device 81 Transfer drum 82 Heat roller 83 Pressure roller 84 Power supply

Claims (5)

[Claims] An image carrier on which an electrostatic latent image is formed, an electrode housing having an opening provided in close proximity to an electrostatic latent image forming surface of the image carrier, and an inside of the electrode housing. A plurality of ink ejection electrodes, some of which are immersed in the ink held at the end thereof and whose tips protrude from the opening, apply a predetermined voltage between the image carrier and the ink ejection electrodes. A recording apparatus comprising: an electric field forming means for adding. 2. The ink discharge electrode is supported by a substrate disposed in the electrode accommodating portion, and a tip of the ink discharge electrode is provided to protrude from an end of the substrate. The recording device according to claim 1, wherein 3. The image forming apparatus according to claim 1, wherein the tip portions of the plurality of ink discharge electrodes are arranged along a lateral direction of the image carrier, and the entire arrangement width of the tip portions is an electrostatic latent image formed on the image carrier. The recording apparatus according to claim 1, wherein the recording apparatus is set to be longer than a width of the carrying area. 4. The apparatus according to claim 1, wherein at least one set of said plurality of ink discharge electrodes is electrically connected to each other, and respective electric potentials are controlled equally using said electric field forming means. The recording device according to claim 1. 5. A device according to claim 1, further comprising a driver for controlling a potential of each of said ink discharging electrodes in synchronization with an image signal of an electrostatic latent image formed on said image carrier.
The recording device according to any one of claims 1 to 4.