JPH07132604A - Recorder - Google Patents

Abstract

PURPOSE:To prevent image irregularities due to vibrations and to form a high resolution image by providing a means to control the drive of a recording means in such a manner that will time irregularly the discharge of ink drops. CONSTITUTION:Timing signals of pulse form to be sent to an electricity-to-heat converter of a recording head form a large cycle A similar to conventional ones, but multiple small cycles a1 to a4 forming a cycle A consist of multiple small signals of different cycles. The electricity-to-heat-converter is heated, and ink is discharged by a predetermined timing. Oscillation waveforms of ink caused by ink drop discharge by each pulse are different from discharge to discharge, therefore, waveforms interfere with each other, making the amplitude smaller. Making vibrations inherent in driving systems, including a belt, irregular as with the timing of discharge mentioned above, will help reduce a deterioration (irregularities, etc.) in image quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus for outputting information such as characters and images on a recording medium in an information processing system such as a copying machine, a facsimile, a printer, a word processor, a personal computer and the like. In particular, the present invention relates to an inkjet recording apparatus equipped with an inkjet recording head.

[0002]

2. Description of the Related Art Conventionally, paper, cloth, plastic sheet, O
A recording apparatus for recording on a recording medium such as a HP sheet (hereinafter also simply referred to as recording paper) can be equipped with recording heads of various recording methods, for example, a wire dot method, a thermal method, a thermal transfer method, and an inkjet method. It has been proposed as a form.

Among these methods, the ink jet method is one of the low-noise, non-impact methods for ejecting ink and directly adhering it to recording paper. It is a continuous method due to the method of forming ink droplets and the method of generating ejection energy fields. It is roughly classified into a charge particle control method and a spray method and an on-demand method (including a piezo method, a spark method and a bubble jet method).

In the continuous system, ink is continuously ejected and only necessary liquid droplets are charged. The charged droplets adhere to the recording paper, and the rest is wasted. On the other hand, in the on-demand method, ink is ejected only when printing is necessary, so that there is no waste of ink and the inside of the device is not contaminated. In addition, the on-demand method starts and stops ink ejection, and therefore has a lower response frequency than the continuous method. Therefore, increasing the number of nozzles realizes high speed. Therefore, most of the recording devices currently on the market are of the on-demand type, and a recording device equipped with such an ink jet type recording head is capable of high-density and high-speed recording operation.
A printer as an output terminal of an information processing system, such as a copying machine, a facsimile, an electronic typewriter, a word processor, a workstation, or a handy or portable printer provided in a personal computer, a host computer, an optical disk device, a video device, or the like. It is used as and is commercialized. In this case, the inkjet recording apparatus has a configuration corresponding to the function, usage pattern, etc. peculiar to these apparatuses.

Generally, an ink jet recording apparatus comprises a recording means (recording head), a carriage on which an ink tank is mounted, a conveying means for conveying recording paper, and a control means for controlling these. Then, the recording head for ejecting ink droplets from the plurality of ejection ports is serially scanned in the direction (main scanning direction) orthogonal to the recording paper conveyance direction (sub-scanning direction), while the recording paper is set to the recording width when not recording. The same amount is intermittently conveyed. This recording method is
Ink is ejected onto a recording sheet according to a recording signal to perform recording, and it is widely used as a quiet recording method with low running cost. Further, by using a recording head in which a large number of nozzles for ejecting ink are arranged in a straight line in the sub-scanning direction, the recording head scans the recording paper once to perform recording with a width corresponding to the number of nozzles. It Therefore, it is possible to speed up the recording operation.

Further, in the case of a color ink jet recording apparatus, a color image is formed by superimposing ink droplets ejected by recording heads of a plurality of colors. Generally, when performing color recording, yellow (Y),
There are required four types of recording heads and ink cartridges corresponding to the three primary colors of magenta (M) and cyan (C) or the four primary colors including black (B). Recently, an apparatus capable of forming an image in full color, which is equipped with such a recording head of 3 to 4 colors, has been put into practical use.

Furthermore, the above-mentioned ink jet recording apparatus can be configured so that large-format recording such as A1 can be performed relatively easily. That is, a plotter such as a printer for CAD output, for example, a recording device compatible with A1 version color recording for connecting a reader for reading an image and copying an original has been commercialized. In addition, on the other hand, various usages have been demanded, and there is an increasing demand for recording on an OHP film which can be projected for presentations at conferences, lectures and the like. In order to meet such demands, when a recording medium having different ink absorption characteristics is selected as needed, a recording apparatus capable of performing the best recording regardless of the type of the recording medium is being developed and commercialized. .

As described above, the ink jet recording apparatus is in high demand in a wide range of industrial fields (for example, the apparel industry) as an excellent recording means, and it is also required to provide higher quality images.

Next, an ink jet recording head (hereinafter also referred to as a recording head) provided in the ink jet recording apparatus will be described.

As the energy generating means for generating energy for ejecting ink in the recording head, one using an electromechanical transducer such as a piezo element or a liquid is heated by an electrothermal transducer having a heating resistor. There are things to do.

Among them, a recording head of a system for ejecting a liquid by utilizing thermal energy (utilizing a film boiling phenomenon) (so-called bubble jet system) is high because the liquid ejection ports can be arranged at a high density. It is possible to record the resolution.

Here, in order to facilitate understanding of the prior art and the present invention, an example of a conventional ink jet recording head and an ink jet recording apparatus equipped with the recording head will be described with reference to FIGS.

FIG. 5 is a sectional perspective view for explaining a schematic structure of an ink jet recording head mounted on the ink jet recording apparatus.

Reference numeral 51 indicates a plurality of grooves 53 which serve as nozzles for passing ink, a groove 54 which serves as a common liquid chamber and communicates with these grooves, and a supply port 55 which supplies ink to the common liquid chamber. Reference numeral 52 denotes a formed top plate, and 52 denotes a substrate on which an electrothermal converter 56 corresponding to each nozzle and an electrode 57 for supplying electric power to each electrothermal converter are integrally formed by a film forming technique. A plurality of ejection ports (orifices) for ejecting ink by combining the top plate 51 and the substrate 52 as described above.
58 is formed.

The recording head 51 having such a structure
Forms an inkjet cartridge together with an ink tank that supplies ink to the recording head from the supply port. FIG. 6 is an external perspective view for explaining a schematic configuration of an inkjet recording apparatus equipped with the inkjet recording head shown in FIG.

In the figure, reference numeral 20 is a platen 2.
Inkjet head (recording head) of an inkjet head cartridge IJC including a nozzle group that ejects ink to face the recording surface of the recording sheet that has been fed onto the recording sheet 4.
Is. 16 is a carriage H for holding the recording head 20
C is a part of the drive belt 18 that transmits the drive force of the drive motor 17, and is slidable with the two guide shafts 19A and 19B that are arranged in parallel to each other. It is possible to reciprocate over the entire width of the recording paper. During this reciprocating movement, the recording head 20 records an image according to the received data on the recording paper. This one
Each time the main scanning is completed, the recording paper is conveyed by a predetermined amount and the sub scanning is performed.

Reference numeral 26 is a head recovery device, which is disposed at one end of the movement path of the recording head 20, for example, at a position facing the home position. The head recovery device 26 is operated by the driving force of the motor 22 via the transmission mechanism 23, and the recording head 20 is capped. In association with the capping portion for the recording head 20 by the cap portion 26A of the head recovery device 26, ink absorption (suction recovery) is performed by an appropriate suction means (for example, a suction pump) provided in the head recovery device 26, As a result, the ink is forcibly ejected from the ejection port, thereby performing the ejection recovery process such as removing the thickened ink in the ejection port.
Further, the recording head is protected by capping at the end of recording. Such an ejection recovery process is performed when the power is turned on, when the recording head is replaced, or when the recording operation is not performed for a certain period of time.

Reference numeral 31 is a blade as a wiping member, which is disposed on the side surface of the head recovery device 26 and is made of silicon rubber. The blade 31 is a blade holding member 31.
The head recovery device 26 is held by A in a cantilever form.
Similarly to the above, the motor 22 and the transmission mechanism 23 operate to enable engagement with the ejection surface of the recording head 20. As a result, the blade 31 is projected into the movement path of the recording head 20 at an appropriate timing in the recording operation of the recording head 20 or after the ejection recovery process using the head recovery device 26. Dew condensation, wetness, dust, etc. on the ejection surface of the head 20 is wiped off.

A bubble jet type ink droplet forming process performed by the recording head having the above structure will be briefly described.

First, when the heating resistor (heater) reaches a predetermined temperature, film bubbles covering the heater surface are generated. The internal pressure of this bubble is very high and pushes out the ink in the nozzle. The ink is moved toward the common liquid chamber outside the nozzle and in the opposite direction by the inertial force due to this extrusion. As the movement of the ink progresses, the internal pressure of the bubble becomes a negative pressure, and the flow path resistance is added, so that the speed of the ink inside the nozzle becomes slow. Since the ink ejected from the nozzle orifice (orifice) is faster than inside the nozzle, the ink is separated and separated into droplets due to inertia force, flow path resistance, bubble contraction, and ink surface tension variation. Simultaneously with the contraction of the bubbles, ink is supplied from the common liquid chamber into the nozzle by the capillary force and waits for the next pulse.

As described above, the recording head using the electrothermal converting element as the energy generating means can generate bubbles in the ink in the liquid passage in a one-to-one correspondence with the driving electric pulse signal, and it can be immediately and appropriately used. Since it is possible to cause the bubbles to grow and contract, it is possible to achieve ink droplet ejection with excellent responsiveness. In addition, the recording head can be easily made compact, and the advantages of IC technology and microfabrication technology, which have been significantly improved in technology and reliability in the recent semiconductor field, can be fully utilized, and high-density mounting is easy. This is advantageous because the manufacturing cost is low.

[0022]

However, in the above-mentioned conventional recording apparatus, there is a problem that vibration during driving of the recording head causes instability of ink ejection.

That is, ink droplets are ejected after foaming and defoaming on the heating resistor (heater) of the electrothermal converting element.
The bubbling generates a force to fly an ink droplet in the ejection direction, and at the same time, pushes the ink in the opposite direction (that is, the common liquid chamber direction) with an equivalent force. This is transmitted as pressure oscillation from the nozzle to the common liquid chamber. Therefore, if a plurality of nozzles discharge at the same time, this pressure vibration will be large, which may affect the inside of the ink tank or the refilling of the ink.
If the ink is not sufficiently supplied and the ink is ejected, image quality is deteriorated due to ejection failure.

Here, the relationship between the ejection timing and the ink vibration state will be described with reference to FIGS. 7 and 8.

As shown in these figures, since the recording head receives an electric pulse signal having a constant pulse width, the ejection timing appears as a constant cycle b1 which matches the pulse cycle. Therefore, with a constant cycle b1, a constant period
Since bubbling and defoaming of the ink occur over B, the amplitude of the vibration of the ink due to this also becomes a constant cycle b1 that matches the cycle of the ejection timing. Therefore, the vibration of the liquid path of the recording head has a large amplitude due to the overlapping of the vibration waveforms. The large amplitude of the ink vibration requires, for example, a time for returning from a violently vibrating state after ink ejection to a steady state, or when the timing for boiling the film does not match the phase within the vibration, an extra amount of ink is ejected Need energy. On the other hand, when the film boiling timing matches the phase in the vibration, it is necessary to limit the frequency for ejecting ink.

Further, the problem of ink vibration is caused not only by the recording head but also by driving the carriage. That is, in an apparatus that forms an image while moving the ink jet recording head mounted on a carriage, the image is formed while a steady vibration is generated by a motor for driving the carriage, a belt, or the like. Since the timing for ejecting ink is always constant, the finally formed image is an image in which the vibration waveform of the carriage appears as it is, and in some cases, an image with periodic unevenness that can be visually recognized. .

Therefore, an object of the present invention is to solve the above problems and to provide a recording apparatus and a recording apparatus capable of always forming a stable and high-quality image without causing image unevenness due to vibration of the recording head or the like. It is to provide an information processing system as an output means.

[0028]

In order to solve the above problems, an ink jet recording apparatus according to the present invention has a carriage having a recording means for recording image information on a recording medium by ejecting ink droplets. The inkjet recording apparatus is characterized in that a means for controlling the drive of the recording means is provided so that the timing of ejecting ink droplets is irregular. Preferably, it has a means for controlling the drive of the carriage so that the movement of the carriage becomes irregular. More preferably, the irregularity of ink droplet ejection timing and / or the irregularity of carriage driving is formed by random numbers. The recording means is preferably an inkjet recording head that uses an electrothermal converter that causes film boiling in the ink as a means for generating energy for ejecting the ink.

Next, an information processing system according to the present invention is characterized by including such a recording device as output means.

[0030]

Since the drive control of the recording means is performed so that the ink droplet ejection timing is irregular, and preferably the carriage drive control is also performed so that the carriage movement is irregular, The amplitude of the vibration waveform of the ink due to the ink droplet ejection becomes small. By forming the irregularity of the ink droplet ejection timing and / or the irregularity of the drive of the carriage by using random numbers, the irregularity is sure.

By using an ink jet recording head using an electrothermal converter that causes film boiling in the ink as a recording means for generating energy for ejecting ink, high-quality and high-density image formation can be performed. Done.

[0032]

EXAMPLES The schematic structure of an ink jet recording apparatus according to the present invention and an ink jet recording head mounted on the apparatus is the same in that it has the components shown in FIGS. It is different in that it has a head drive section capable of controlling the ink ejection timing described in section 1 and that the print operation is controlled so that an appropriate print operation can be performed by this drive section.

FIG. 1 shows an example of a recording operation control system of an ink jet recording apparatus according to the present invention.

In this figure, reference numeral 1 is a host computer connected to the recording apparatus. The computer 1 sends an external signal 2 including recording data and various commands to a micro processing unit (MP) of a recording device.
U, also called central processing unit CPU) 3. MPU3
Processes the input external signal 2 and sends control signals 7 and 10 to the head drive unit 6 and the motor drive unit 9. The head drive unit 6 is electrically connected to the recording head 4,
The electrothermal converter 5 of the recording head 4 is driven. On the other hand, the motor drive unit 9 drives the carriage 8 carrying the recording head 4.

FIG. 2 is for explaining the ink ejection timing controlled by the control system having the configuration shown in FIG.

The head drive unit 6 sends a pulse-shaped control (timing) signal corresponding to a predetermined ink ejection timing to the electrothermal converter 5 of the recording head 4 based on the control signal sent from the MPU 3. The timing signal has the same large cycle A as the conventional one, but the plurality of small cycles a1 to a4 constituting the large cycle A are different from the conventional one. That is, it is composed of a plurality of small pulse signals having different periods. Based on this, the electrothermal converter generates heat and ink is ejected at a predetermined timing. By causing the ink to be ejected at the ejection timings of different cycles in this way, the vibration waveform of the ink caused by the ejection of the ink droplets by each pulse is different for each ink droplet ejection, so that the waveforms interfere with each other and the waveforms of FIG. The vibration waveform is as shown in. This vibration waveform has a smaller amplitude than the conventional one.

On the other hand, the periodic vibrations of the carriage driving motor 8 driven by the motor driving unit 9 and the vibrations peculiar to the driving system such as the belt driven by the driving motor 8 are similar to the ejection timing shown in FIG. It is possible to suppress the deterioration of image quality (unevenness, etc.), which has been a problem in the conventional apparatus, by providing irregularity in the.

It is also possible to use random numbers as a method for forming various ejection timings having irregularity. For example, a1 to a4 in which all ejection timings are predetermined
It is possible to use a random number of

As another method using random numbers, in order to keep the cycle A constant, for example, a1 to a3 are selected by random numbers, and the sum of the selected a1 to a3 is subtracted from A to obtain a.
4 can be set.

FIG. 4 shows a second example of the recording operation control system of the ink jet recording apparatus according to the present invention, which forms the ejection timing shown in FIG. 2 similarly to the control system shown in FIG. However, the following points are different.

The control system in this figure is constructed as follows because the number of signal lines of the connecting cable is reduced.
That is, the shift register 12, the latch circuit 13, and the drive timing generation circuit 14 are interposed between the head drive unit 6 and the recording head 4.

In this control system, a serial drive control signal 11 is sent from the head drive section 6 to the shift register 12 through a cable. The serial drive control signal 11 can drive the electrothermal converter 5 of the head 4 via the shift register 12 and the latch circuit 13. On the other hand, a drive timing signal 15 and a common drive signal, and a signal 16 such as VH are sent to the drive timing generation circuit 14 via a cable.

As described above, in the present embodiment, the head drive section 6 or the drive timing generation circuit 14 is provided as a means for controlling the drive of the recording means such that the timing of ejecting ink droplets becomes irregular. , Or by adding, and preferably by providing a motor drive unit 9 as a means for controlling the drive of the carriage so that the movement of the carriage becomes irregular,
By reducing the amplitude of ink vibration in the ink liquid path of the recording head, it is possible to maintain a steady state without requiring extra energy, and also to reduce image quality (image unevenness) due to carriage drive. It becomes possible to prevent it.

(Others) The present invention is particularly provided with means for generating heat energy as energy used for ejecting ink (for example, an electrothermal converter or a laser beam) even in the ink jet recording system. The present invention brings about excellent effects in a recording head and a recording apparatus of a system that causes a change in the state of ink by thermal energy. This is because such a system can achieve high density recording and high definition recording.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
It can be applied to any of the continuous type, but especially in the case of the on-demand type, it can be applied to the sheet holding the liquid (ink) or the electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recording information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and film boiling is caused on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal in a one-to-one correspondence
It is effective because bubbles can be formed inside. Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angle liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration corresponding to the ejection portion is disclosed in JP-A-59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording medium which can be recorded by the recording apparatus. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the main body of the apparatus or the ink jet from the main body of the apparatus is electrically connected to the main body of the apparatus by being mounted on the main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, as the constitution of the recording apparatus of the present invention, it is preferable to add the ejection recovery means of the recording head, the preliminary auxiliary means and the like because the effects of the present invention can be further stabilized. Specifically, heating is performed by using a capping unit, a cleaning unit, a pressure or suction unit for the recording head, an electrothermal converter or a heating element other than this, or a combination thereof. Examples thereof include a preliminary heating unit for performing the discharge and a preliminary discharge unit for performing discharge different from the recording.

Regarding the type and number of recording heads mounted, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. A plurality of pieces may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but it may be either the recording head is integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for an apparatus provided with at least one of full-color recording modes by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature may be used. Or, in the inkjet system, it is common to control the temperature of the ink itself within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature so that the viscosity of the ink is within the stable ejection range. Sometimes, a liquid ink may be used. In addition, the temperature rise due to thermal energy is positively prevented by using it as the energy of the state change of the ink from the solid state to the liquid state, or in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent No. 1260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the ink jet recording apparatus of the present invention may be used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function. It may be a form or the like.

And, without being limited to the above fields,
The ink jet recording apparatus of the present invention may take a form used as an apparatus for printing a cloth made of cotton, silk, rayon, acetate, nylon, polyester fiber or the like and a mixed spinning cloth thereof.

[0054]

As described above, the ink jet recording apparatus according to the present invention is an ink jet recording apparatus having a carriage equipped with recording means for recording image information on a recording medium by ejecting ink droplets. A means for controlling the drive of the recording means is provided so that the timing of ejecting the ink droplets is irregular, and preferably a means for controlling the drive of the carriage is also irregularly arranged. Since the recording means is driven so that the timing of ejecting ink droplets is irregular and the drive of the carriage is also irregularly controlled, the amplitude of the vibration waveform of ink due to the drive of the recording head and the carriage is small. As a result, deterioration of image quality is suppressed, and it is possible to always form stable and high-quality images. It is possible to provide an information processing system output means recording device and the device.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating an example of a control system of an inkjet recording apparatus according to the present invention.

FIG. 2 is a diagram for explaining control of ink ejection timing by the inkjet recording apparatus according to the present invention.

FIG. 3 is a diagram for explaining an irregular change in a vibration waveform of ink accompanying ink ejection controlled by an inkjet recording device according to the present invention.

FIG. 4 is a block diagram for explaining another example of the control system of the inkjet recording apparatus according to the present invention.

FIG. 5 is a cross-sectional perspective view for explaining a schematic configuration of an inkjet recording head mounted in a conventional inkjet recording device.

FIG. 6 is a perspective view for explaining a schematic configuration of a conventional inkjet recording device.

FIG. 7 is a diagram for explaining control of ink ejection timing by a conventional inkjet recording apparatus.

FIG. 8 is a diagram for explaining an irregular change in an ink vibration waveform associated with ink ejection controlled by a conventional inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Host computer 2 External signal 3 MPU 4 Inkjet recording head 5 Electrothermal conversion element 6 Recording head drive unit 7 Control signal 8 Drive motor 9 Motor control unit 10 Control signal 11 Serial drive control signal 12 Shift register 13 Latch circuit 14 Drive timing generation Circuit 15 Drive timing signal 16 Signal

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B41J 3/10 101 F

Claims (5)

[Claims] 1. An inkjet recording apparatus having a carriage equipped with recording means for recording image information on a recording medium by ejecting ink droplets, wherein the timing of ejecting the ink droplets is irregular. An inkjet recording apparatus comprising means for controlling drive of the recording means. 2. The ink jet recording apparatus according to claim 1, further comprising means for performing drive control of the carriage such that movement of the carriage becomes irregular. 3. The ink jet recording according to claim 1, wherein the irregularity of the ink droplet ejection timing and / or the irregularity of the carriage drive is formed by a random number. apparatus. 4. The recording apparatus according to claim 1, wherein the recording unit is an electric heater that causes film boiling in the ink as a unit that generates energy for ejecting the ink. An inkjet recording apparatus, which is an inkjet recording head using a converter. 5. An information processing system comprising the recording device according to claim 1 as output means.