JPH09254413A - Ink jet head used for gradation recording, ink jet head cartridge, ink jet apparatus and method for ink jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet head which can discharge the ink of small to large volumes at a suitable speed and refill the ink at a high speed by respectively providing a plurality of ink discharge units having different ink discharging amounts at a plurality of ink channels to guide the ink to the discharge ports. SOLUTION: This ink jet head is formed with an ink supply port 2 on a silicon board 1 by anisotropic etching to discharge ink droplets from discharge ports t, t' for constituting a discharge port via an ink channel 3 from an ink supply port 2 having a width of 57.1μm. Heating elements (heaters) H, h for constituting the discharge unit are disposed together with the discharge port corresponding to the ports t, t' substantially directly under the ports t, t' provided for the one ink channel. With such a constitution, ink droplets having different sizes can be satisfactorily discharged, and gradation recording of high image quality can be performed. The discharge ports themselves can also be arranged in high density, and further highly minute recording can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet head, an ink jet head cartridge, an ink jet apparatus and an ink jet recording method for recording ink on a recording material by ejecting ink droplets by pressure generated by the generation of bubbles.

[0002]

2. Description of the Related Art An ink jet head is a device for applying electric energy to a heater to generate bubbles and ejecting ink droplets by the pressure of the bubbles to record on a recording material.
It is widely used due to its quiet operation, the possibility of high density, and the ease of colorization.

In order to drive an ink jet head stably with high energy efficiency and at high speed, various contrivances have hitherto been made for high density recording.

As a method of performing gradation recording using an ink jet head, Japanese Patent Laid-Open Nos. 55-132258 and 63-160853 disclose a heater having a gradient in width and thickness in one ink passage. There is disclosed a recording liquid ejecting head in which a heater is provided and a plurality of heaters are provided.

In general, as a method for efficiently ejecting ink droplets, as disclosed in Japanese Patent Laid-Open No. 5-16365, there is a method of communicating with the atmosphere in the process of growing bubbles. is there. In this method, since the distance between the heating resistor and the discharge port is short, the ratio of the work done by the bubbles to the electric energy given to the heater is better than that of the recording liquid ejecting head before that. Further, since almost all the ink between the heater and the ejection port is ejected, there is an advantage that the volume of the ejected ink is stabilized.

[0006]

However, the above-mentioned conventional example has the following problems to be solved.

First, in a head that discharges ink by communicating air bubbles with the atmosphere, small droplets (15 × 10 ^-15
m ³ ) or less) is relatively good, but when trying to eject a relatively large droplet of ink, it is necessary to enlarge the ejection port, and as a result, the size of the ejection port is The ejected liquid droplet becomes flattened far beyond the distance between the heater and the ejection port, and the ejection direction becomes unstable. Moreover, the capillary force at the time of refilling decreases and the refilling time becomes longer,
High-speed recording cannot be performed.

On the other hand, in the case of a head in which the ejection openings for ejecting very small droplets are arranged at a high density, conventionally, the ink passages and the ejection openings have a one-to-one correspondence, and therefore each ink passage is thin. Therefore, the flow path resistance becomes high, and the refill time becomes long.

Next, in order to perform gradation recording, a heater having a gradient in width and thickness or a plurality of heaters are arranged in one ink passage communicating with one ejection port. In the case of a misaligned head, the volume of the ejected ink droplet and the flying speed have a correlation, and this influence deteriorates the quality of the recorded image.

That is, if the standard is to fly a large droplet at an appropriate ejection speed, the flying speed of a small droplet becomes low, the ejection direction becomes unstable, and it becomes difficult to stabilize the image. On the other hand, if the standard is to make small droplets fly at an appropriate ejection speed, the flying speed of large droplets will significantly increase, and so-called jumping will occur when landing on the recording material, and the image tends to become dirty.

An object of the present invention is to provide an ink jet head, an ink jet head cartridge, an ink jet device and an ink jet recording method which can eject a small volume to a large volume of ink at an appropriate speed and can be refilled at a high speed. . Another object of the present invention is to provide a recording liquid ejecting head and the like which can perform good gradation recording.

[0012]

The ink jet head of the present invention for achieving the above object is as follows.

A plurality of ink flow paths for guiding the ink to the ejection port, and the ejection port and the ink provided in the ejection port are caused to act on the ink in the ink channel to eject the ink. And a discharge element configured to generate a bubble for generating a bubble, and a plurality of ink discharge sections having different ink discharge amounts are provided in each ink flow path.

The ink jet head cartridge of the present invention is a head cartridge having the above-mentioned ink jet head and an ink container for holding ink to be supplied to the ink jet head, and the ink jet apparatus of the present invention is the above ink jet head. And a recording medium conveying unit that conveys the recording medium that receives the ejected ink.

Further, in the ink jet recording method of the present invention, the ejection portion constituted by the heating element for generating heat for ejecting the ink and the ejection port for ejecting the ink is provided for one ink flow path. This is a recording method in which a plurality of heads are used to selectively drive the plurality of ejection units to eject different amounts of ink from the ejection ports, thereby performing recording.

(Operation) With such a configuration and method, ink droplets of different sizes can be ejected favorably, and high-quality gradation recording can be achieved. Further, since the ejection openings themselves can be arranged at a high density, it is possible to achieve higher definition recording.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIGS. 1A and 1B are views for explaining a first embodiment of an ink jet head according to the present invention. FIG. 1A is a plan view and FIG. 1B is a drawing. A-A '
It is a line sectional view.

The head has an ink supply port 2 formed on a silicon substrate 1 by anisotropic etching. Width 57.
Droplets are ejected from the 1 μm ink supply port 2 through the ink flow path 3 and the ejection ports t and t ′ that constitute the ejection portion. A heating element (heater) H, which constitutes an ejection portion together with the ejection port corresponding to each of the ejection ports t and t ′, is formed substantially directly below the ejection port t and t ′ provided for one ink flow path. , H is located. Reference numeral 4 is a partition wall 4'constituting the ink flow path and a flow path constituent member (nozzle material) having the above-described ejection port, which is formed by a known manufacturing method such as an exposure technique or etching. Reference numeral 5 indicates a protective film.

The heaters H and h are arranged side by side in the y direction at a pitch of 84.7 μm, and are arranged in a staggered manner with the supply port 2 sandwiched therebetween being offset by 84.7 / 2 μm. The head prints while scanning in the x direction. This head performs recording at a pixel pitch (both in the x and y directions) of 84.7 μm. t and t '(or H and h) pair up to 80 per second
Pixel recording is performed 00 times. Therefore, the main scanning speed of the head is (84.7 / 2 μm) × 8000 / sec = 338.
It is 8 mm / sec.

Reference numeral 4'denotes a partition (for separating each ink flow path) which fluidly separates adjacent pairs and has a width of 12.7.
μm, and the end is 10 μm from the end of the supply port. The sheet resistance of the heater is 80Ω, the wiring resistance is about 0.2Ω, the waveform of the drive signal (pulse) is a rectangular wave, and the drive voltage is 14.
The heater H has a pulse width of 5 V, 4.0 μsec, and the heater h has a pulse width of 2.5 μsec. The ink used is DE
G. 80%, water 20% C. I. It is a product in which 4% of Food Black 2 is dissolved.

The size of the discharge port t is 25 μm × 25 μm,
The size of the discharge port t'is 18 μm × 18 μm, heater H
Is 32 μm × 32 μm, and the size of the heater h is 24 μm × 24 μm. The thickness of the nozzle material 4 is 20μ
m, of which the thickness of the discharge port is 9 μm.

When the heaters H and h are individually driven, the volumes of ink ejected from the ejection ports t and ^t'are 11 × 10 ^-15 m ³ and 5 × 10 ^-15 m ³ , respectively. Also, when these are driven at the same time, 11 × 10 from t
^-15 m ³ , ^{5'10 -15} m ³ of ink is ejected from t ',
Ejection can be performed on the same pixel. Therefore, in each pixel, 0 m ³ , 5 × 10 ⁻¹⁵ m ³ , 11 × 10 ⁻¹⁵ m ³ , 16 ×
The recording of four levels of ink amount of 10 ⁻¹⁵ m ³ can be selected by the image data. When driven simultaneously, the discharge speed was 19 m / s from t and 18 m / s from t '. The refill time is 95 μsec on the t side and 70 μs on the t ′ side.
ec.

FIG. 2 is a wiring pattern diagram of the heaters H and h of FIG. Reference numeral 11 is an Al wiring layer of a common electrode, reference numeral 11 'is an Al wiring layer of an individual electrode of h, and reference numeral 11 "is H.
Is an Al wiring layer of the individual electrode of FIG. Reference numeral 12 is a heater layer (HfB ₂ layer). The relative positions of the partition wall and the heater are L ₁ = 3 μm and L ₂ = 92 μm in the figure. The size of the heater H is 32 μm × 32 as described above.
Since it is μm, the shortest distance between H and h is 92 μm-3 μm-3
2 μm = 57 μm. This value is sufficiently larger than the distance between the heater and the tip of the ejection port of 20 μm so that the ink is not ejected from the other ejection port by driving either H or h.

FIG. 3 is a graph showing the meniscus amplitude of the ejection port t '(the ejection port directly above h) when H is driven when the center distance between the heaters H and h is changed. According to this, it is understood that even if h and H come close to each other, ink droplets cannot be ejected from the ejection port t ′ even if they come close to each other. In the case of this example, the liquid path height (9 μm) is extremely low, and the distance between the heater and the discharge port (20 μm) is short, and thus such a property is exhibited.

The distance between the centers of H and h is 92 μm +
(24 μm / 2) -3 μm- (32 μm / 2) = 85 μm
Although the distance is about 2 pixels in m, it is actually an integer pixel ±
There is no problem if it is set to about 20 μm. Further, the distance between the corresponding heaters sandwiching the supply port 2, for example, the distance in the x direction between H in the right column and h in the left column in FIG. 1 is 254.1 μm.
Is exactly 6 pixels apart. Therefore, in the case of the right column, H records two pixels ahead of h, and the right column records six pixels ahead of the left column.

In order to prevent ink from being ejected from the other ejection port when ink is ejected individually from each ejection port as described above, the distance OH from the heater to the ejection port is 30 μm or less. Therefore, it is more desirable that HC / OH> 1 (HC; distance between heater centers).

FIG. 4 shows a drive circuit for one pair of heaters in this example. Symbol VH in the drawing indicates a head drive power source, a indicates a drive signal input portion of the heater h, and b indicates a drive signal input portion of the heater h.

This head has 128 pairs of heaters on one side of the supply port and a total of 256 pairs of heaters. The driving order is 16 pairs in order from the top (+ y direction), and the blocks are sequentially driven in 16 blocks. ing. Since the time difference between adjacent blocks is 7 μsec, for example, when recording a vertical line, the straight line shifts for each block and becomes oblique as a whole for each scanning. To avoid this, set the head to ta with respect to the y-axis.
Scanning was performed with a tilt of n ^-1 (2.3716 / 677.6).

In this example, four heads (black,
By using (yellow, magenta, cyan), 42.
It was possible to perform 4-value color recording at a pitch of 35 μm (600 dpi).

As a modified example of this example, instead of tilting the head as described above, there is also a method of maintaining the linearity of vertical line recording by shifting the distance between the heater and the supply port end by 2.37 μm for each drive block. Needless to say.

Further, although the heaters H and h and the orifices t and t'are made different in this embodiment, the present invention is not limited to this, and the present invention can be carried out even when one size is made different. There is no problem in doing it.

In the head of this example, the type of ejection was such that it was ejected from the ejection port and communicated with the atmosphere while the bubbles generated on the heater were growing.

(Second Embodiment) FIG. 5 is a view for explaining a second embodiment of the ink jet head according to the present invention. FIG. 6 is a wiring pattern diagram of the heaters H and h corresponding to the discharge ports t and t ′ of FIG. 5, respectively.

In this example, unlike the first example, two large and small heaters per pixel are arranged in the y direction instead of the x direction. This example is a head having 1200 pixels / 25.4 mm in the x direction and 600 pixels / 25.4 mm in the y direction.
The number of heaters is 64 pairs on the left and right sides. Outlet t,
t ′ is 16 μm × 16 μm and 13 μm × 13 μ, respectively
The heater size corresponding to each discharge port is 20 μm (width) × 24 μ (length) for the heater H and 15 μm (width) × 20 μm (length) for the heater h. Also,
The distance between the centers of the heaters is 22 μm. The thickness of the nozzle material 24 is 17 μm, of which the orifice portion is 8 μm. The discharge volumes when the heaters H and h are driven individually are 5 × 10 ^-15 m ³ and 3 × 10 ^-15 m ³ , respectively, and the volumes when both are driven simultaneously are approximately 8 × 10 ^-15 m ³ . . The ejection speed at this time was 18 m / s from the ejection port t, 16 m / s from the ejection port t ′, and the refill time was 60 μsec on the ejection port t side and 45 μsec on the ejection port t ′ side.
When one of the heaters H and h was driven, the meniscus vibrated from the other orifice port, but the droplet was not discharged. FIG. 5 is a wiring diagram of the heater, and the drive circuit is the same as in the first embodiment.

In FIG. 5, the discharge port pair (t ₁ ,
t ′ ₁ ), (t ₂ , t ′ ₂ ), ... Are arranged with a period of 8 pairs, and the x coordinate difference between adjacent pairs is 5.3.
0 μm, driving (t _{8n + 1} , t ′ _{8n + 1} ), (t _{8n + 2} , t ′
_{8n + 2} ) ..., (t _{8n + 7} , _{t'8n + 7} ) (n = 0, 1,
2, 3, 4, 5, 6, 7) and the driving time difference between adjacent blocks is 12.5 μsec.

Using this head, 600 × 1200 pixels /
It was possible to satisfactorily carry out four-value recording at 25.4 ² mm ² .

(Third Embodiment) In the first and second embodiments, the flow path corresponding to one pixel and the flow path corresponding to the adjacent pixel are separated by the partition walls, but this embodiment has a plurality of pixels. In the case where the minute heater also includes a heater that is driven at the same time, it is characterized in that it is arranged in one flow path without being partitioned by partition walls.

FIG. 7 is a layout view of ejection ports in a third embodiment of the ink jet head according to the present invention. In this figure, the discharge ports 411 to 414 are located directly above a heater group (4 heaters) (not shown) that are driven simultaneously,
Four ejection ports are arranged in one ink flow path 43. The size of the discharge ports 411 and 412 is 22 μm × 22 μ
m, heater size 26 × 32 μm ² and discharge amount 8
It is × 10 ⁻¹⁵ m ³ (8 pl). Meanwhile, the size is 17 × 17 .mu.m ² of the discharge ports 413 and 414, the corresponding heater size is 24 × 26 .mu.m ^2, the discharge amount of 4 × 10 ^-15
It becomes m ³ (4 pl). If the left row of ejection ports is a large ejection port, the ejection ports located in the X-axis direction are small ejection ports (413, 41).
4), and the ejection ports are arranged in the X direction in order of size. Therefore, when recording is performed by scanning the head in the X-axis direction, it is possible to superpose ink droplets having large and small ink ejection amounts in one pixel by one scan. Therefore, by recording with this head, 0 pl, 4 p
It is possible to achieve recording with four gradations of 1, 8 pl, and 12 pl.

The arrangement pitch of the ejection ports 411 and 412 is 35.4 μm and the ejection ports on the opposite side of the ink supply port 42 are arranged in a staggered manner, so that the pixel density is 35.4 μm.
It becomes m / 2. The adjacent heater group, which separates the partition wall, ejects ink at a timing 8 μsec apart from the main heater group.

The thickness of the nozzle material is 20 μm, and the thickness of the discharge port portion is 8 μm, so the flow path height is 12 μm. Ink is not ejected from the adjacent ejection ports in the same block 35.4 μm apart by driving one heater, and the meniscus only slightly vibrates. Therefore, as long as the four heaters surrounded by the partition wall are driven at the same time, there is no interaction that affects the ejection. However, if multiple heaters that are driven at different timings are placed in the same block, for example, when a high pressure bubble is generated from another heater while the meniscus is being refilled at a certain discharge port, a very small droplet is discharged. It is not preferable because it may cause adverse effects such as being lost.

Also in this example, the discharge speed was 15 m / s and the refill time was 120 μsec.

(Embodiment 4) Also in this embodiment, as in the previous embodiment, a plurality of ejection ports capable of ejecting different amounts of ink to be driven simultaneously are provided in one flow path. There is.

FIG. 8 is a schematic plan view showing the arrangement of the ejection ports of the ink jet head of this embodiment. Similar to the previous embodiment, the ejection ports 511 to 514 are arranged at positions facing the heater.

In this embodiment, four ejection ports for ejecting different amounts of ink are provided in the ink flow path 53 branched from the ink supply port 52 for supplying the ink to the head. The discharge ports 511, 512, 513, 514 are 28 × 28 μm ² , 22 × 22 μm ² and 17 × 17 μm, respectively.
² and 13 × 13 μm ² , and the corresponding heater sizes are 34 × 34 μm ² and 26 × 3, respectively.
4 μm ² , 26 × 26 μm ² , 24 × 24 μm ² and 4
They are arranged at a pitch of 2.2 μm. The discharge amount of such a discharge unit is 17.6 × 10 ⁻¹⁵ m ³ (17.6p), respectively.
l), 8.8 × 10 ⁻¹⁵ m ³ (8.8 pl), 4.4 × 1
0 ^-15 m ³ (4.4 pl), 2.2 × 10 ^-15 m ³ (2.2
pl). The other structure of the head is similar to that of the previous embodiment.

When recording is performed by scanning such a head, if one pixel is recorded by a plurality of scans, it is an integral multiple of 2.2 pl and a maximum of 16 pl of 16 pl.
A gradation can be achieved. When printing is performed by two scans, in the areas where printing is performed by 511 and 512 in the first scan, printing may be performed by 513 and 514 in the second scan.

(Other Embodiments) FIG. 9 shows that the ink jet head having the ejection port 11 of the present invention and the ink container 15 holding the ink to be supplied to the ink jet head can be separated at the position of the boundary line K. It is the connected inkjet head cartridge 17. The inkjet head cartridge is provided with an electrical contact (not shown) for receiving an electrical signal from the carriage side when the cartridge is mounted on the carriage on the apparatus side, and the head is driven by the electrical signal. To be done.

A fibrous or porous ink absorber is provided in the ink container constituting the head cartridge for holding the ink, and the ink is held by these ink absorbers.

FIG. 10 is an external view of an example of an ink jet recording apparatus in which the ink jet recording head having the above structure is mounted. The inkjet recording device IJRA has a lead screw 2040 that rotates via driving force transmission gears 2020 and 2030 in association with forward and reverse rotations of a drive motor 2010. The carriage HC on which the inkjet cartridge IJC in which the inkjet recording head and the ink tank are integrated is placed,
Carriage shaft 2050 and lead screw 2040
Supported by the lead screw 2040, the rhombus groove 204
1 has a pin (not shown) to be engaged with 1, and as the lead screw 2040 rotates, arrows a, b
It is reciprocated in the direction. Reference numeral 2060 denotes a paper pressing plate that presses the paper P against the platen roller 2070 that constitutes a conveying unit that conveys the recording medium in the carriage movement direction. Reference numerals 2080 and 2090 denote photocouplers, which operate as home position detecting means for confirming the presence of the lever 2100 provided on the carriage HC in this area and switching the rotation direction of the motor 2010. Reference numeral 2110 is a member that caps the entire surface of the recording head, and is supported by a support member 2120.
2130 is an absorbing means for absorbing the inside of the cap,
The suction recovery of the recording head is performed through the opening in the cap.
A cleaning blade 2140 for cleaning the end face of the recording head is provided on a member 2150 so as to be movable in the front-rear direction, and these are supported by a main body support plate 2160. The blade 2140 is not limited to this form,
It goes without saying that a known cleaning blade can be applied to this example. Further, 2170 is a lever for recovering the suction of the suction recovery, which is moved along with the movement of the cam 2180 engaging with the carriage HC, whereby the driving force from the driving motor 2010 is switched to the clutch. The movement is controlled by known transmission means such as.

The capping, cleaning, and suction recovery are configured so that desired processing can be performed at their corresponding positions by the action of the lead screw 2040 when the carriage HC comes to the home position side area. Any desired operation can be applied to the present example.

Further, the ink jet device of the present invention has a drive signal supply means for giving a signal for driving the heating element of the ink jet head of the present invention to the head.

[0052]

As described above, according to the present invention, ink can be ejected at an appropriate speed even for ink droplets having a small volume and ink droplets having a large volume. As a result, high definition and gradation recording can be achieved. In addition, since a plurality of discharge parts that discharge different amounts are arranged in one flow path, the discharge port arrangement density can be made extremely high. Further, according to the structure of each embodiment, it is possible to optimize the ink ejection speed and improve the refill time.

[Brief description of drawings]

1A and 1B are views for explaining a first embodiment of a recording liquid ejecting head according to the present invention, in which FIG. 1A is a plan view and FIG. 1B is a sectional view taken along the line AA ′ in FIG. It is a figure.

FIG. 2 is a wiring pattern diagram of heaters H and h in FIG.

FIG. 3 is a graph showing a meniscus amplitude of a discharge port t ′ when H is driven when the center distance between heaters H and h is changed.

FIG. 4 is a drive circuit for one pair of heaters in FIG.

FIG. 5 is a diagram for explaining a second embodiment of the inkjet head according to the present invention.

6 is a wiring pattern diagram of heaters H and h corresponding to the discharge ports t and t'of FIG. 5, respectively.

FIG. 7 is a diagram for explaining a third embodiment of the inkjet head according to the present invention.

FIG. 8 is a layout view of ejection ports in a fourth embodiment of the inkjet head according to the present invention.

FIG. 9 is a schematic diagram for explaining the configuration of the inkjet head cartridge of the present invention.

FIG. 10 is a schematic diagram for explaining the configuration of the inkjet device of the present invention.

[Explanation of symbols]

 1 Silicon substrate 2, 22, 32, 42 Ink supply port 3, 23, 33 Ink flow path 4, 24, 34, 44 Nozzle material 4 ', 24', 34 ', 44' Partition wall 5 Protective film 11 Common electrode (Al Layer) 11 'Individual electrode of heater h (Al layer) 11 "Individual electrode of heater H (Al layer) 12 Heater layer h, H heater t, t', 411-414 Discharge port

Claims (15)

[Claims] 1. A plurality of ink flow paths for guiding ink to an ejection port, the ejection port, and ink by applying thermal energy to the ink provided in the ejection port in the ink channel. An ink jet head having a heating element configured to generate bubbles for ejecting ink, and an ejection unit configured of, wherein a plurality of the ink ejection units having different ink ejection amounts are provided in each of the ink flow paths. Inkjet head characterized in that 2. The ink jet head according to claim 1, wherein the ejection port and the heating element forming the ejection unit face each other. 3. The plurality of ink ejecting units have different ejection port sizes or heating element sizes.
2. The inkjet head according to item 1. 4. The plurality of ink ejection portions have different ejection openings or heating elements.
2. The inkjet head according to item 1. 5. A plurality of ink flow paths for guiding the ink to the ejection port, and the ink by applying thermal energy to the ink in the ink channel provided in the ejection port and the ejection port. An ink jet head having an ejecting section composed of a heating element for emitting bubbles for ejecting, and a plurality of the ink ejecting sections having different ink ejecting amounts are provided in each of the ink flow paths, and the ink jet head. And an ink container that holds ink supplied to the inkjet head cartridge. 6. The ink jet head cartridge according to claim 5, wherein the ejection port and the heating element forming the ejection unit face each other. 7. The plurality of ink ejecting units have different ejection port sizes or heating element sizes.
The inkjet head cartridge described in 1. 8. The size of the ejection port or the size of the heating element is different in the plurality of ink ejection units.
The inkjet head cartridge described in 1. 9. A plurality of ink flow paths for guiding the ink to the ejection ports, and the ink by applying thermal energy to the ink in the ink channels provided in the ejection ports and the ejection ports. An ink jet head having a discharge part formed of a heating element for generating bubbles for discharging the ink, and a plurality of ink discharge parts having different ink discharge amounts are provided in each of the ink flow paths; An inkjet apparatus, comprising: a recording medium conveying unit that conveys a recording medium that receives ejected ink. 10. The ink jet apparatus according to claim 9, wherein the ejection port and the heating element forming the ejection unit face each other. 11. The ink jet apparatus according to claim 9, wherein the plurality of ink ejection portions have different ejection port sizes or heating element sizes. 12. The size of the ejection port or the size of the heating element of the plurality of ink ejection units are different from each other.
The inkjet device according to item 9. 13. A head provided with a plurality of ejection portions for one ink flow path, each of which is composed of a heating element for generating heat for ejecting ink and an ejection port for ejecting ink, An ink jet recording method, wherein recording is performed by ejecting different amounts of ink from the ejection ports by selectively driving the plurality of ejection units. 14. The ink jet recording method according to claim 13, wherein one pixel is formed by overlapping different amounts of ink. 15. The ink jet recording method according to claim 13, wherein bubbles are generated in the ink by the generation of the heat, and the bubbles are communicated with the atmosphere to eject the ink.