JP3382563B2 - Ink jet recording apparatus and ink jet recording method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus and an ink jet recording method.
The present invention relates to reduction of ink mist that occurs when ink is ejected.

[0002]

2. Description of the Related Art In recent years, there have been remarkable advances in colorization, speedup, and high image quality in ink jet recording systems. With the spread of the Internet and digital cameras, the demand for color recording that is comparable to photographic quality is increasing.

As a method for achieving such high-definition and high-quality recording with gradation in the ink jet recording system, the size of the ejection port for ejecting ink in the recording head is reduced to increase the array density. At the same time, the ink droplets ejected from the ejection port are made smaller to record a small dot, thereby improving the resolution of the recorded image, and a dark ink for one color is used without increasing the ejection port density. A plurality (at least two or more) including a head for ejecting and a head for ejecting a light ink having a density lower than this ink
A method of preparing the heads of the above and performing overprinting as necessary, thereby improving the gradation of the recorded image and improving the image quality, ejection from these ejection ports without increasing the ejection port density A method is known in which the amount of ink is made variable so that the size of dots to be printed can be changed within a relatively large range, the gradation is improved, and the image quality is improved.

However, a so-called bubble jet method (hereinafter, referred to as a bubble jet method) in which bubbles are formed in the ink by the thermal energy generating element and the ink is ejected by the foaming pressure at that time
The bubble-jet method) is generally said to be difficult to implement.

On the other hand, in the above method, if the number of shades of one color ink is more than two, the number of print heads used may increase and the cost may increase. For this reason, it is general to use two kinds of dark and light ink for one color ink. Therefore, in this case, the number of gradations of light and shade is limited, and there is a certain limit in pursuit of high image quality.

From the above points, in the bubble-jet method,
The method of performing recording by ejecting relatively small ink droplets from one ejection port as in the above method is effective in terms of high image quality. Such small droplets (10 in discharge volume)
As a method for ejecting the ink (pl or less), it is a kind of bubble-jet method, in which the generated bubbles are communicated with the outside air in the vicinity of the ejection port before the ink droplet leaves the ejection port (hereinafter, this system). Is also referred to as a “bubble through method” or a “BTHJ method”).
It is known in Japanese Patent Laid-Open No. 0940, Japanese Patent Application Laid-Open No. 4-10941, Japanese Patent Application Laid-Open No. 4-10742, and the like. In addition,
Hereinafter, of the bubble-jet methods, methods other than the BTHJ method, that is, methods that perform discharge without communicating with the outside air near the discharge port are referred to as bubble-jet methods.

In the bubble-jet method, the smaller the ejected ink droplet is, the thinner the liquid flow path communicating with the ejection port from which the ink droplet is ejected is required. In this case, the ejection efficiency is lowered and the ejection speed is also lowered. When the ejection speed decreases in this way, the ejection direction and ejection amount become unstable, and the ejection becomes unstable due to the thickening due to the evaporation of ink moisture when the recording head is not ejecting, initial ejection failure, etc. Are likely to occur, and reliability problems are likely to occur.

On the other hand, the BTHJ method is suitable for ejecting small droplets, and the amount of ejected droplets is mainly determined by the geometrical shape of the ejection port. It has the advantages that it is less susceptible to the effects of temperature and the like, and the ejection amount of ejected droplets is relatively stable compared to the bubble-jet method.

[0009]

However, in general, the smaller the size of the liquid droplets ejected from the ejection port, the more the number of times ink is ejected to fill a predetermined recording area. Therefore, the amount of satellites generated with the ejection of the ink droplets also increases with the increase in the number of times of driving. Further, increasing the number of times of driving may bring about a decrease in throughput, and therefore it is considered to increase the number of ejection ports to compensate for this decrease.
This increase in the number of ejection ports further increases satellites.

As described above, when the amount of satellites is increased, the mist in the device is increased, resulting in a problem of stains in the device.
In the worst case, the problem arises that mist adheres to the electrical contact portion and causes malfunction of the printer. Even when the liquid droplets are not made so small, when the above-mentioned method is combined with the above method and two recording heads of dark and light are used, the number of heads increases and the amount of satellites to be ejected also increases. Similar problems occur.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ink jet recording apparatus and an ink jet recording method capable of suppressing an increase in ink mist associated with higher image quality. To provide.

[0012]

The present invention has been made based on the following characteristics of satellites in the bubble-jet system and the BTHJ system, which the inventors of the present invention have studied.

1 (a), 1 (b), 1 (c) and 1 (d)
FIG. 4 is a schematic diagram showing a process of ejecting ink droplets in the bubble-jet method over time. On the other hand, as shown in FIG.
(B), (c) and (d) are schematic diagrams showing a similar process in the BTHJ method. In these FIGS. 1 and 2, 4 is a discharge port, 11 is a main droplet, and 12 is a satellite.

In principle, in the BTHJ method, all the ink in front of the heater is ejected. Moreover, since there is no defoaming process as in the bubble-jet method, the timing at which the main droplet leaves the ejection port is earlier than in the bubble-jet method. In this way, in the BTHJ method, since all the ink in front of the heater is ejected in principle, satellites do not occur, but in reality, a part of the ink remains on the wall surface of the ejection port and is pulled by the main droplets, as shown in FIG. Tail as shown. The tail thickness d _BTJ is characteristically smaller than in the case of the bubble-jet method (d _BJ shown in FIG. 1A). At the time point shown in FIG. 2B, the tail length is lengthened by being pulled by the velocity of the main droplet portion, and when the surface tension to be united is overcome, a plurality of satellites as shown in FIG. Divided into. The BTHJ satellites 12 (FIG. 2D) thus formed are generally larger in number and smaller in size than the bubble-jet satellites 12 (FIG. 1D). In the bubble-jet method, satellites are, as shown in FIG.
The thick tail makes it difficult for satellites to split into multiple parts, and the number of satellites is small.

As described above, in the bubble-jet method, the size of the satellite is about 0.1 to 6 pl in volume. On the other hand, the volume of satellites in the BTHJ method is about 0.01 to 0.5 pl, which is smaller than that of bubble jets, and there is a large number of satellites.

The present invention has been made as a result of research on the phenomenon of satellites of the BTHJ method and the bubble-jet method. That is, a recording head that has a thermal energy generating element that generates thermal energy according to the ejection port and the applied energy, and ejects at least the main ink droplet from the ejection port by the pressure of the bubble generated in the ink by the thermal energy. In an ink jet recording apparatus that performs recording by using a high duty ratio , a high duty ratio is set according to an ejection duty obtained based on binary image data in a predetermined recording area.
And means for distinguishing the tea portion and a low duty portion, wherein
When performing recording on the high duty portion, the energy applied to the thermal energy generating element is made relatively small so that ink is ejected in a state where the bubbles are not in communication with the atmosphere, and the low duty portion is discharged. And record
In this case, the energy applied to the thermal energy generating element is relatively increased so that the generated bubbles communicate with the atmosphere.
The thermal energy is generated so that the ink is ejected.
And a control means for controlling the energy applied to the raw element .

Further, it has a thermal energy generating element for generating thermal energy according to the ejection port and the applied energy, and at least the main ink droplet is ejected from the ejection port by the pressure of the bubble generated in the ink by the thermal energy. In the inkjet recording method for performing recording using the recording head, the high duty is increased according to the ejection duty obtained based on the binary image data in the predetermined recording area.
Section is distinguished from the low duty section, and the high duty
-When recording on the upper part, the thermal energy generated
The energy applied to the element is made relatively small so that the ink is ejected in a state where the bubbles generated in the ink do not communicate with the atmosphere, and recording is performed on the low duty portion.
In this case, the energy applied to the thermal energy generating element
It is characterized in that recording is performed by making the bubble relatively large and communicating the generated bubbles with the atmosphere to eject ink.

According to the above configuration, the low duty portion is
On the other hand, when recording is performed , the ink is ejected by a method (BTHJ method) in which bubbles in the ink communicate with the atmosphere. Here, since the duty is low, few satellites are generated as a whole. Further, since the volume of the discharged small droplets is uniform and small, it is possible to obtain a high-quality image in which the graininess is not conspicuous and there is no unevenness.

On the other hand, recording is performed in the high duty area.
Cormorants time bubble method that does not communicate with the atmosphere - it is possible to reduce the satellite itself generated since ink is ejected in (bubble jet system). In the case of the bubble-jet method, there is a possibility that the discharge volume may not be uniform,
Since the duty is high, there are almost no dots formed independently, and there is no problem in terms of image quality. Further, it is possible to prevent a decrease in throughput.

[0020]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

(Embodiment 1) FIGS. 3A and 3B
3A and 3B are diagrams showing a schematic configuration of an inkjet recording head according to the present embodiment. FIG. 3A is a cross-sectional view of an ink ejection port viewed from a side, and FIG. 3B is a front view of the ejection port. It is a front view.

In the ink jet recording head of this embodiment, 256 ejection ports are arranged at a density of 600 dpi,
The volume of the ink droplet ejected from each ejection port is 8.5 pl. A rectangular heater 1 as an electrothermal conversion element is provided at a predetermined position on the element substrate 2. An orifice plate 3 is arranged in parallel with the upper portion of the substrate 2, and the orifice plate 3 has a discharge port 4 opening in a rectangular shape at a position facing the heater 1. The space surrounded by the substrate 2, the orifice plate 3 and the liquid flow path wall 6 forms the communication passage 105 and the liquid flow path 5 communicating with the communication passage 105. As shown in FIG. 3B, the liquid flow path 5 extends in the x direction shown in the figure, and in this case, a plurality of discharge ports 4 are arranged in the y direction. Further, the recording head of this embodiment has the same configuration as that shown in FIGS. 3A and 3B symmetrically with respect to the y-axis. That is, two rows of the ejection ports 4 arranged in the y direction are formed.

Next, regarding the present embodiment, depending on the energy applied by applying a voltage pulse to the heater 1, the discharge by the above-mentioned BTHJ system (hereinafter also referred to as “BTHJ discharge”) and the discharge by the bubble-jet system (hereinafter referred to as “BTHJ discharge”). , (Also referred to as “bubble-jet ejection”) will be described. FIG. 4 is a diagram illustrating the concept of this control.

In FIG. 4, Eth is the bubbling threshold energy or the ejection lower limit energy. When the input energy to the heater 1 is equal to or smaller than Eth, the bubbling required for ejecting the liquid cannot be obtained and the ink is not ejected. . If the input energy is larger than Eo,
As shown in FIG. 5A, sufficient energy is supplied to eject substantially all of the ink in front of the heater 1 in the ejection direction, and BTHJ ejection is performed. on the other hand,
If the input energy is smaller than Eo, the energy required to eject all the ink in front of the heater 1 cannot be obtained, and the bubble-jet ejection state as shown in FIG. In this case, the energy E applied for bubble-jet discharge is 1 ² <E / Eth <
(1.1) ² , where Eo / Eth = (1.1) ² .

As shown in FIGS. 5 (a) and 5 (b), it is determined whether the discharge state is BTHJ discharge or bubble-jet discharge, immediately after discharge in the discharge direction in front of the heater 1 in the discharge direction. This can be easily determined by observing whether or not ink remains in the area up to 4. That is, when ink is not left in front of the heater 1 as in the case shown in FIG. 7A, BTHJ is ejected, and when ink is left as shown in FIG. It can be determined that the bubble-jet is being discharged.

In one embodiment of the present invention, control is performed to switch the bubble-jet discharge and the BTHJ discharge controlled as described above according to the print duty of the image. Here, the high duty part in the image data used for the control is defined. The high-duty portion is a predetermined area in the binary image data, and is a portion in which more than half of the pixels in that area are on (ejection) data. On the other hand, the low duty portion is a portion in which less than half of the pixels have on-data.

In the ink jet recording apparatus of the present embodiment, the high duty and the low duty are distinguished according to whether the number of pixels ejected in the predetermined recording area is 1/2 or less as described above. / 2
Of course, it is not limited to. As for this criterion, the state of mist may be checked in advance for every several duties, and the criterion may be set based on this.

Next, concrete means for changing the input energy in the above control will be described. In the bubble-jet method or the BTHJ method according to this embodiment, the input energy can be changed by the shape of the voltage pulse applied to the heater. When only one pulse shown in FIG. 6A is added (hereinafter, also referred to as “single pulse”), as shown in FIG. 6B, foaming occurs before the ejection pulse (hereinafter, main pulse). When a short pulse (hereinafter referred to as “prepulse”) that is not allowed (hereinafter also referred to as “double pulse”) is applied, the double pulse has a larger input energy. Note that the period from the fall of the pre-pulse to the rise of the main pulse is called a pause time.

In the head of this embodiment, the flow path height Th shown in FIG. 3A is 13 μm, the orifice plate thickness To is 12 μm, the heater size is a 26 μm square, and the heater area Sn is 676 μm ^2. Is. Figure 3
The discharge port area An shown in (b) is 400 μm ² , and the volume discharged from the head is 8.5 pl in the BTHJ method when a voltage of 9 V is applied to the heater.

At the time of low duty, it is driven by a double pulse having a voltage of 9 V, a pre-pulse width of 0.5 μsec, a dwell time of 1.0 μsec, and a main pulse width of 1.6 μsec.
As a result, the BTHJ ejection state as shown in FIG. 2 is obtained. On the other hand, at high duty, the voltage is 9V and 1.9.
Drive with a single pulse of μsec width. This allows
A bubble-jet discharge state as shown in FIG. 1 is obtained.
As described above, by ejecting BTHJ at the time of low duty, the droplets ejected from the head can be made relatively small and the volume thereof can be kept constant to obtain a high-definition image without unevenness. At the same time, since the duty is low, the total satellite amount can be reduced, and the amount of mist in the device can be reduced. On the other hand, at the time of high duty in which there are almost no dots that are formed in isolation, by performing bubble-jet ejection, the satellite itself can be reduced and the amount of mist can be reduced as well. Since this is good, it is possible to prevent a decrease in throughput.

In the present embodiment, the BTHJ ejection and the bubble-jet ejection are switched by increasing / decreasing the pulse width, but the inventors of the present application have made earnest studies and found that the switching is the structure of the head. It has been found to have a close relationship with.

In the head structure of FIG. 3 (a), whether or not to bubble through is determined by the front inertance in the ejection direction,
It depends on the balance with the backward inertance in the flow direction. T ₀
Is shorter, that is, the thinner is the orifice plate, the smaller is the front inertance in the discharge direction, and the easier is BTJ discharge. Similarly, the shorter the distance Th in the flow path height direction, the greater the rear inertance in the flow path direction, and the more the power does not escape in the flow path direction, the easier the BTHJ discharge. On the other hand, if the thickness T _{0 of the} orifice plate is large, the front inertance on the discharge direction side becomes large and it becomes difficult to discharge BTHJ. Similarly, the longer the distance Th in the flow path height direction, the smaller the rear inertance in the flow path direction, and the power escapes in the flow path direction, making it difficult to eject BTHJ.

By increasing or decreasing the pulse width, BTHJ
It has been found that the nozzle structure of the head capable of switching ejection and bubble-jet ejection has the following relationship.

When the value is smaller than 0.5 <T ₀ / Th <1.5 0.5, there are two cases where T ₀ is extremely small and Th is large. In the former case,
Due to manufacturing limitations, the orifice plate cannot be made extremely small to the order of a few μm, so in reality, the orifice plate is extremely thin, and stable BTHJ discharge is possible with almost no forward inertance in the discharge direction. Have difficulty. Next, in the latter case, Th increases, rear inertance decreases, power does not concentrate in the discharge direction, and the power escapes in the flow path direction, so stable BTHJ discharge is difficult.

As Comparative Example 1 of this embodiment, T ₀ = 15
Even in the case of the head having μm and Th of 12 μm, it was possible to switch the pulse width as in the present embodiment. However, as Comparative Example 2, in the case of the head having T ₀ = 18 μm and Th = 12 μm, BTHJ ejection could not be stably performed.

Further, as Comparative Example 3 of the second embodiment, T
In the case of the head structure of h = 16 μm and T ₀ = 9 μm, the pulse width could be similarly switched. However, as Comparative Example 4, in the case of a head having Th = 18 μm and T ₀ = 9 μm, BTHJ ejection could not be stably performed.

In the embodiment of the present invention, T ₀ + Th is 2 as a condition for more stable BTHJ ejection.
The range of about 0 μm to 30 μm is a particularly preferable condition. When T ₀ + Th is less than that, the following reasons can be considered.

When Th is 10 μm or less, the response frequency of the head is lowered.

When T ₀ is 6 μm or less, it becomes difficult to form a robust orifice.

If T ₀ + Th is much larger than 30 μm, only ordinary bubble-jets are likely to occur.

(Embodiment 2) The recording head of this embodiment has To of 9 μm and Th of 12 μm shown in FIG. Heater size is 26μm × 31μm
And has Sn of 806 μm ² . Figure 3
An shown in (b) is 400 μm ² , and when a voltage of 10 V is applied to the heater, the volume ejected from the head in the BТHJ method is 5 pl.

In this embodiment, the bubble-jet method,
In any of the BHHJ methods, the single pulse drive described above is performed, and the input energy applied to the heater is changed by increasing or decreasing the pulse width. That is, at low duty, the voltage is 10 V and the pulse width is 2.3 μsec.
Drive with. This allows the BTH as shown in FIG.
J ejection state is set. On the other hand, at the time of high duty, driving is performed with a single pulse having a voltage of 10 V and a pulse width of 1.8 μsec, and bubble-jet ejection as shown in FIG. 1 is performed. The bubbling threshold pulse width or the ejection lower limit pulse width Pth of the recording head of the present embodiment is 1.5 μsec, and the drive pulse P at the time of bubble-jet ejection is 1 ²
The relationship of <(P / Pth) <(1.1) ² is satisfied. In this way, BTHJ ejection is performed at low duty,
On the other hand, by performing bubble-jet discharge at the time of high duty, it is possible to reduce satellites and reduce mist inside the aircraft, as in the first embodiment.

(Third Embodiment) In the third embodiment, the driving voltage is increased or decreased as a means for changing the energy input to the heater. That is, at the time of low duty, a single pulse with a voltage of 10 v and a pulse width of 2.3 sec is used for driving. As a result, the BTHJ ejection state as shown in FIG. 2 is obtained. On the other hand, at high duty, the voltage is 9V,
Driving with a single pulse having a pulse width of 2.3 μsec, bubble-jet ejection as shown in FIG. 1 is performed. At this time, the drive voltage V at the time of bubble-jet ejection is 1 <
The relationship of (V / Vth) <1.1 is satisfied. in this way,
By performing BTHJ ejection at low duty, while performing bubble-jet ejection at high duty, the same effects as those of the above-described two embodiments can be obtained.

FIG. 7 is a perspective view showing an example of the ink jet printing apparatus according to each of the above-mentioned embodiments.

In FIG. 7, reference numeral 130 is a carriage on which two ink jet heads and two ink cartridges can be mounted. Of the two ink jets, one has a predetermined number of ejection ports for ejecting cyan, magenta, and yellow inks integrally formed, and accordingly, the ink cartridge separately stores the above three types of inks. It is to store. The other ink jet head ejects black ink, and the other ink cartridge stores the black ink accordingly. Carriage 130
Is slidably supported by guide rails 132 and 133, both ends of which are supported and extended by the chassis 131. A drive belt 134 for transmitting drive from a drive motor (not shown) to the carriage 130.
And a flexible cable 135 for transmitting an image signal to the mounted head 10, respectively. As a result, printing can be performed by ejecting ink from each inkjet head 10 onto a recording medium, such as a recording medium.

At the home position HP provided at one end side of the carriage movement range, a cap (capping means) 136 used for suction or protection for the purpose of recovery of ejection to the ink jet head mounted on the carriage 130 is provided. Has been. The cap 136 is used, and the cap 1 is provided by a pump (pump means) not shown.
By making the space between 36 and the head part negative pressure,
Alternatively, by performing preliminary ejection on the cap 136, it is possible to positively eliminate clogging of the ejection port of the head portion or the ink flow path (ejection port) communicating with this. Although not shown, an ink tube communicating with the inside of the cap 136 and guiding the ink discharged from the head portion to a predetermined portion is attached to the cap 136.

FIG. 8 is a block diagram showing the control arrangement of the ink jet recording apparatus shown in FIG.

The control unit 800 has a CPU 801 which executes processing of recording data, operation control processing of each mechanism, and the like, and controls the recording apparatus. ROM 802 is the CP
Stores the processing program by U801 and also RAM
Reference numeral 803 is used as a work area for processing execution by the CPU 801. Further, the CPU 801 can control the drive of the carriage motor 806 and the paper feed motor 807 via the motor drivers 806D and 807D.

The drive control of each ink jet head shown in FIG. 7 is performed by the head controller 804 based on the control of the CPU 801. That is, the head drive controller 804 supplies binary ejection data stored in the one-line memory to the driver of the inkjet head 808 in association with each ejection port of the inkjet head 808 in accordance with the timing of movement of the carriage 130. Based on this, ink is ejected from the inkjet head 808.

At this time, in the above-described first embodiment, C
The PU 801 counts the number of ON (ejection) data when storing the print data for one line from the predetermined buffer in the one-line memory 805, and stores this in the predetermined memory of the head drive controller 804. Then, when the ejection data stored in the 1-line memory 805 is transferred to the inkjet head 808, as described above, the duty obtained based on the count number is equal to or greater than a preset reference duty. A waveform signal of a drive pulse is sent from the waveform setting unit 804A to the driver of the inkjet head 808, and the heater is driven with a drive pulse having a pulse width or a voltage value according to the duty.

[0051]

As is apparent from the above description, according to the present invention, the system in which the bubbles in the ink communicate with the atmosphere (BTHJ system) when printing is performed on the low duty portion.
Ink is ejected. Here, since the duty is low, few satellites are generated as a whole. Further, since the volume of the discharged small droplets is uniform and small, it is possible to obtain a high-quality image in which the graininess is not conspicuous and there is no unevenness.

On the other hand, recording is performed for the high duty part.
Cormorants time bubble method that does not communicate with the atmosphere - it is possible to reduce the satellite itself generated since ink is ejected in (bubble jet system). In the case of the bubble-jet method, there is a possibility that the discharge volume may not be uniform,
Since the duty is high, there are almost no dots formed independently, and there is no problem in terms of image quality. Further, it is possible to prevent a decrease in throughput.

As a result, the amount of mist discharged into the recording apparatus can be reduced while maintaining both high speed and high image quality.

[Brief description of drawings]

FIG. 1A to FIG. 1D are schematic diagrams showing in chronological order the states of ink droplets and satellites during bubble-jet ejection.

FIG. 2A to FIG. 2D are schematic diagrams showing the states of ink droplets and satellites during BTHJ ejection in time series.

FIG. 3A is a cross-sectional view showing a configuration of a main part of an inkjet recording head according to an embodiment of the present invention from a lateral side of an ejection port, and FIG. 3B is a front view of the configuration.

FIG. 4 is a diagram showing a relationship between energy applied to a thermal energy generating element and a discharge state.

FIG. 5A is a BTHJ of an inkjet recording head.
FIG. 3B is a schematic view of the vicinity of the discharge port at the time of discharge as seen from the side surface, and FIG. 7B is a schematic view of the vicinity of the discharge port at the time of bubble-jet discharge as viewed from the side face.

6A and 6B show drive pulses applied to the thermal energy generating element in the present embodiment, FIG. 6A is a diagram showing a single pulse, and FIG. 6B is a diagram showing a double pulse having a prepulse.

FIG. 7 is a perspective view showing an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 8 is a block diagram showing a control configuration of the inkjet recording apparatus shown in FIG. 7.

[Explanation of symbols]

1 Heater 2 Element substrate 3 Orifice plate 4 Discharge port 5 Liquid channel 6 Liquid channel wall 105 _{Communication} channel 11 Main droplet 12 Satellite Th Channel height To Channel thickness Sn Orifice plate thickness Sn Heater area An Discharge port area d _BTJ BTHJ During discharge Thickness of ink droplets of the ink droplet d _BJ bubble-thickness of ink droplets when jetting

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/05 B41M 5/00

Claims (14)

(57) [Claims] 1. A thermal energy generating element that generates thermal energy in accordance with an ejection port and applied energy, and at least a main ink droplet is ejected from the ejection port by the pressure of bubbles generated in the ink by the thermal energy. In an ink jet recording apparatus that performs recording using a recording head, the high duty section and the low duty section are selected according to the ejection duty obtained based on the binary image data in the predetermined recording area.
A means for distinguishing between a tee portion and an ink ejected in a state where the energy applied to the thermal energy generating element is relatively small when recording is performed on the high duty portion so that the bubbles do not communicate with the atmosphere. And perform recording on the low duty section.
When performing, the energy applied to the thermal energy generating element is made relatively large and the generated bubbles are released into the atmosphere.
The thermal energy is used so that ink is ejected by communicating with each other.
-Control means for controlling the energy applied to the generating element
An ink jet recording apparatus comprising the and. 2. The recording head comprises the low duty
2. The ink jet recording apparatus according to claim 1, wherein the ink is ejected after the generated bubbles are communicated with the atmosphere by the energy applied by the control unit when recording is performed on the copy. . 3. The means for applying the energy to be applied to the thermal energy generating element in the form of a pulse, and controlling the energy by changing the shape of the pulse. The inkjet recording device according to item 1. 4. The inkjet according to claim 3, wherein the means controls the energy by using a plurality of pulses including a combination of a pulse directly related to ink ejection and a pulse other than the pulse. Recording device. 5. Recording is performed on the low duty portion.
In this case, the pulse in the case of being composed of a plurality of pulses including a combination of a pulse directly related to the ejection of ink and a pulse other than that, and when recording is performed on the high duty portion.
The ink jet recording apparatus according to claim 4, wherein the pulse is a single pulse. 6. Recording is performed on the high duty portion.
Energy E to be applied to the thermal energy generating element when cormorants
1 ² <E / Eth <(1.1) ² Here, Eth is the ejection lower limit energy required for ejection, and the inkjet recording apparatus according to any one of claims 1 to 5. 7. The recording is performed on the high duty portion.
In this case, the width P of the pulse applied to the heat energy generating element
However, 1 ² <(P / Pth) <(1.1) ² Here, Pth is an ejection lower limit pulse width required for ejection, and inkjet recording according to any one of claims 3 to 5. apparatus. 8. The generated bubbles are discharged by communicating with the atmosphere.
The ejected ink droplet is divided into the main droplet and the main droplet.
The ink droplet according to claim 1, which is a broken satellite droplet.
Recording device. 9. A thermal energy generating element that generates thermal energy in accordance with an ejection port and applied energy, and at least an ink main droplet is ejected from the ejection port by the pressure of bubbles generated in the ink by the thermal energy. In the ink jet recording method for performing recording using the recording head, the high duty part and the low duty part are selected according to the ejection duty obtained based on the binary image data in the predetermined recording area.
When the recording is performed on the high duty portion by distinguishing from the tee portion ,
The energy applied to the thermal energy generating element is relatively
The ink is ejected in a state where air bubbles generated in the ink do not communicate with the atmosphere by making it small, and
When recording on the other hand,
An ink jet recording method, wherein recording is performed by relatively increasing the energy to be applied and communicating the generated bubbles with the atmosphere to eject ink. 10. The step of performing the recording, the energy applied to the thermal energy generating element is applied in the form of a pulse, the shape of the pulse is made different to control the energy, and the ejection is communicated to the atmosphere. Alternatively, the ink jet recording method according to claim 9 , wherein ejection is performed without communicating with the atmosphere. 11. The method according to claim 10, wherein the recording step controls the energy using a plurality of pulses including a combination of a pulse directly related to ink ejection and a pulse other than the pulse. Inkjet recording method described. 12. Recording to the low duty portion
The pulse to be performed is composed of a plurality of pulses including a combination of a pulse directly related to ink ejection and a pulse other than that, and when recording is performed on the high duty portion.
The ink jet recording method according to claim 11, wherein the combined pulse comprises a single pulse. 13. A recording is performed on a high duty portion.
Energy E given to the thermal energy generating element in this case
1 ² <E / Eth <(1.1) ² Here, Eth is the ejection lower limit energy required for ejection, and the inkjet recording method according to any one of claims 9 to 12. 14. Recording is performed on a high duty portion.
In this case , the width P of the pulse applied to the heat energy generating element
^{There, 1 2 <(P / Pth} ) <(1.1) 2 where, Pth jet recording according to any one of claims 9, characterized in that a discharge lower limit pulse width required for discharge 12 Method.