JP3984706B2 - Image recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet image recording apparatus that records an image by ejecting ink droplets onto a recording material.
[0002]
[Prior art]
In recent years, with the progress of office automation and the spread of personal computers and the like, ink jet printers using ink jet print heads for recording digital images on personal computers are rapidly spreading.
[0003]
In addition, in order to shorten the printing time of the digital image and improve the image quality of the output image, a recording head (hereinafter referred to as a multi-recording head) in which a plurality of recording elements are integrated and ink discharge ports and ink flow paths are integrated at high density. Head) is the mainstream.
[0004]
Furthermore, in order to cope with colorization of an image, one having a plurality of the multiheads is generally used.
[0005]
However, with the generalization of color image recording using multicolor ink, in addition to image quality when recording only in monochrome, color development, reproducibility, gradation, uniformity, etc. are also important for image quality. It is an element.
[0006]
In particular, with regard to the uniformity of color image recording, slight variations in nozzle units that occur in the multi-head manufacturing process adversely affect the printing accuracy of each nozzle, resulting in variations in the amount and direction of ink ejection during printing. To make it happen. This variation in the manufacturing process eventually becomes the density unevenness of the recorded image and causes the image quality to deteriorate.
[0007]
Therefore, as a measure for preventing density unevenness due to nozzle variation, for example, Japanese Patent Application Laid-Open No. 60-107975 proposes a method of recording an image while a multi-head is scanned a plurality of times in the main scanning direction.
[0008]
According to this method, in order to complete the recording of the entire nozzle width area of the multihead in which a plurality of nozzles are arranged, the multihead is scanned three times in the main scanning direction, and the area of each half of all the pixels of the multihead width is scanned. Each recording is completed in two scans. In this case, all the nozzles of the multi-head are divided into the upper half and lower half groups of the head, and the dots formed by one nozzle in one scan are thinned out in half according to a predetermined image data arrangement. Corresponding to In the second scan, image output is completed by forming dots corresponding to the remaining half of the image data.
[0009]
In the recording method, an image is usually recorded in accordance with an image data array (mask pattern) so that the image data divided in the first scan and the second scan complement each other. As this mask pattern, as shown in FIGS. 21A and 21B, a pattern in which vertical and horizontal pixels are in a staggered pattern is generally used. In the first scan, dots corresponding to the image data thinned out using the pattern of FIG. 21A are formed in the unit recording area, and in the second pattern, the inverted staggered lattice shown in FIG. 21B is formed. A dot corresponding to the thinned image data is formed using a pattern. Thus, the image of the unit recording area is output by two scans.
[0010]
As described above, since the image in the unit recording area is recorded using two different types of nozzles, it is possible to record a high-quality image without density unevenness.
[0011]
FIG. 2 is a perspective view showing a schematic configuration of a conventional image recording apparatus.
[0012]
As shown in FIG. 2, when the carriage 202 at the home position before printing starts receives a printing start command, the carriage 202 reciprocates in the main scanning direction (X-axis direction) to thereby n multi-nozzles on the multi-head 206. Are reciprocated on the recording area of the divided recording material. When ink ejection to the recording material by the forward movement is completed and the carriage 202 reaches the carriage inversion position, the carriage 202 starts the backward movement toward the home position 201. When the carriage 202 reaches the carriage reversal position on the home position side, the carriage 202 starts the forward movement again.
[0013]
The recording material 204 is conveyed by the rotation of the recording material conveyance roller 203 and the recording material discharge roller 205 from the end of the first printing by the reciprocating movement of the carriage 202 to before the start of the second printing. Is done. This feed amount is controlled so as to be fed in the main scanning direction (Y direction) by the divided recording area width. In this way, the image output is completed by repeatedly performing printing by the multi-head and conveyance of the recording material for each scan of the carriage.
[0014]
FIG. 3 is a block diagram showing a general inkjet image recording apparatus.
[0015]
As shown in FIG. 3, reference numeral 301 denotes a CPU, and a ROM 302 and a RAM 303 are connected to the internal bus. The CPU 301 reads the program from the ROM 302 and executes the program by repeating read / write to the RAM 303. An interface 304 performs command transfer and image data transfer between the image recording apparatus and an external host device (not shown), and is connected to the CPU 301 and a band memory 307 described later. Reference numeral 305 denotes an operation / display unit for displaying input operations and operation states using various keys, and is connected to the CPU 301. Reference numeral 307 denotes a band memory. Image data for printing is transferred from the interface 304, and image data necessary for image recording in a recording area divided into a predetermined width as image data for one band is controlled by the CPU 301. Stored. The output of the band memory 307 is input to the multipath data processing unit 308. Under the control of the CPU 301, the multi-pass data processing unit 308 performs image data thinning processing so that image recording of the divided print areas is completed by a plurality of scans, generates image data for one scan, Output to the controller 309. Reference numeral 309 denotes a head controller whose output is connected to the multi-head 310. Under the control of the CPU 301, the head controller 309 drives the multi-head 310 so that image recording of a print area divided into a predetermined width is performed while the carriage performs one scan operation. The multi-head 310 is controlled by the head controller 309, and ejects ink from a plurality of ink ejection ports formed on the head, and executes image recording for one scan in synchronization with the carriage operation.
[0016]
FIG. 6 is a diagram showing a head position and a recorded image at the time of multi-pass printing set to two passes.
[0017]
As shown in FIG. 6, in two-pass printing, an image is recorded by ejecting ink while a carriage on which a head is mounted reciprocates on a recording material, and ½ bandwidth is used for each scanning operation. The recording material is transported. In one scan operation, the image data thinned out for the adjacent pixels in the image data for one band is recorded. Then, image recording for one band is completed by two scans.
[0018]
[Problems to be solved by the invention]
However, even if the recording area is divided and recorded as in the conventional example, the adverse effect of density unevenness is not completely eliminated.
[0019]
For example, if an ink supply operation or a head recovery operation is required during a printing operation, and it takes time from the end of the first scan to the start of the second scan, this is caused by a difference in the printing time, particularly in high duty printing. It is known that density changes appear as density unevenness (time difference unevenness).
[0020]
Here, density unevenness due to a printing time difference will be described with reference to FIGS. 9 and 10 show how ink permeates and fixes on the recording material when the time interval between the two scans is short and when the image recording for the predetermined recording area is completed by two scans. FIG.
[0021]
9 and 10, reference numeral 801 denotes an ink droplet, and 802 denotes a recording material. The ink droplet 801a that has permeated the recording material 802 in the first scan permeates in a direction perpendicular to the paper surface and a direction spreading on the paper surface, and a pigment such as a dye as an ink component is physically and chemically bonded to the recording material. To do.
[0022]
FIG. 9 is a diagram illustrating a case where the time interval between the first pass and the second pass is short.
[0023]
In FIG. 9, after the first pass printing, the ink droplet 801b in the second pass also penetrates in the direction perpendicular to the recording material and the direction spreading on the surface of the recording material, but in the area where the previously landed 801a is fixed. Does not penetrate or settle well. The cause is considered to be that the ink droplet 801a that has landed first is still penetrating, and that the chemical bond between the recording material and the ink component is finite. Therefore, the ink droplet 801b that has landed later penetrates and fixes further downward in the region where the ink droplet 801a that has landed earlier has permeated.
[0024]
FIG. 10 is a diagram illustrating a case where the time interval between the first pass and the second pass is long.
[0025]
In FIG. 10, ink droplets 801b that have landed later permeate a relatively large amount in the area that has landed first and penetrated and fixed. This is because the ink droplet 801a that has landed first spreads sufficiently and the volatile component has evaporated, so that the amount of the ink droplet 801a per unit volume decreases, and the ink droplet 801b that landed later can penetrate. It is thought that it was because it became.
[0026]
That is, the longer the time interval between the first pass and the second pass, the larger the amount of ink that is fixed near the surface of the recording material, that is, more dyes and ink components such as dyes remain. Further, since the density corresponds to the absorption of light of the dye fixed near the surface of the recording material, the density becomes higher as the time interval becomes longer.
[0027]
As described above, when an image is recorded by the divided recording method, if printing in the midway pass is interrupted, density unevenness occurs in the images before and after the interruption.
[0028]
In view of the above-described problems, the present invention aims to perform other operations such as ink supply and head recovery without causing density unevenness even when printing is interrupted when performing recording by band division, and then performing the printing operation. An image recording apparatus and an image recording method that can be resumed are provided.
[0029]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve the object, an image recording apparatus according to the present invention includes a head having a plurality of ink ejection openings with respect to a unit recording area of a recording material. 3 In an image recording apparatus that records an image by scanning twice, a transport unit that transports the recording material, a pattern selector that selects a second mask pattern for determining an ink discharge port used for recording in each scan, The second mask pattern and the image data to be recorded in the unit recording area are 3 Based on a first mask pattern to be divided into multiple scans, the image data is thinned to generate thinned image data for each scan, and the transport means, the pattern selector, and the head are controlled. Control means for executing recording before and after resuming recording based on the thinned-out image data, and the control means (A) performs the recording between two scans immediately before the recording interruption. The conveyance means is controlled so as not to convey the recording material between two scans immediately after resuming the recording, and the recording immediately before the recording is interrupted for the unit recording area where the recording is completed immediately before the recording is interrupted. The second mask pattern is selected so that different ink ejection port groups are used in the two scans, and immediately after the recording is resumed for the unit recording area where the recording is started immediately after the recording is resumed. The first recording for executing the recording before the recording interruption and after the resumption of recording by controlling the pattern selector so as to select the second mask pattern so that the same ink discharge port group is used in the scanning of one time. The conveying means is controlled so that the recording material is conveyed between the two scans immediately after the restart of recording, and (B) the recording material is not conveyed between the two scannings immediately before the interruption of recording. The second mask pattern is selected so that the same ink discharge port group is used in the two scans immediately before the recording interruption for the unit recording area where the recording is completed immediately before the recording interruption, and immediately after the recording is resumed. The pattern selector is controlled to select the second mask pattern so that different ink ejection port groups are used in the two scans immediately after the recording is resumed with respect to the unit recording area where recording is started. It, the second recording operation to execute the recording after the recording interruption before and recording resuming a selectively feasible.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments according to the present invention will be described below in detail with reference to the accompanying drawings.
[First Embodiment]
FIG. 4 is a schematic block diagram of an image recording apparatus equipped with an ink jet recording head according to a typical embodiment of the present invention.
[0032]
As shown in FIG. 4, 401 is a CPU, and ROM 402 and RAM 403 are connected to its internal bus. The CPU 401 reads the program from the ROM 402 and executes the program by repeating read / write to the RAM 403. Reference numeral 404 denotes an interface for transferring commands and image data with an external host device (not shown), and is connected to the CPU 401 and a band memory 407 described later. Reference numeral 405 denotes an operation / display unit that displays various key input operations and operation states on the apparatus, and is connected to the CPU 401. A mask pattern selector 406, which will be described later, is connected to and controlled by the CPU 401, and its output is connected to a multipath data processing unit 408, which will be described later. Reference numeral 407 denotes a band memory. Image data for printing is transferred from the interface 404, and image data necessary for printing an area divided into a predetermined width is stored as image data for one band under the control of the CPU 401. . The output of the band memory 407 is input to the multipath data processing unit 408. The multi-pass data processing unit 408 performs image data thinning processing so that printing of the divided areas is completed by a plurality of scans under the control of the CPU 401, generates image data for one scan, and the head controller Output to 409. Reference numeral 409 denotes a head controller whose output is input to the multi-head 410. Under the control of the CPU 401, the head controller 409 drives the multi-head 410 so that printing of an area divided into a predetermined width is executed while the carriage performs one scan operation. The multi-head 410 is controlled by the head controller 409, and ejects ink from a plurality of ink discharge ports formed on the recording head, and executes printing for one scan while synchronizing with the carriage operation.
[0033]
Next, an operation (two-pass printing) in which the image recording apparatus according to the present embodiment prints an area having a predetermined width by two scans will be described.
[0034]
FIG. 1 is a diagram illustrating changes in the head position and the distribution positions of the ink ejection ports when the two-pass printing operation is paused and resumed. FIG. 5 is a flowchart showing the control operation of the CPU 401.
[0035]
In FIGS. 1, 4 and 5, first, when a print request command is input to the CPU 401 via the interface 404, the CPU 401 writes image data for one band in the band memory 407 (step S501).
[0036]
Next, the multipath data processing unit 408 reads all image data for one band from the band memory 407 (step S502). Next, the CPU 401 refers to a result flag of the ink remaining amount detection process and a counter that counts up the number of scan lines, and determines whether or not there is a request for interrupting the printing operation. If there is no interruption request in step S503 (NO in step S503), the multi-pass data processing unit 408 performs a thinning process for performing two-pass printing (step S504). This thinning process is realized by masking the image data read from the band memory 407 with a predetermined mask pattern.
[0037]
In this embodiment, the mask pattern for thinning out image data to be printed in the first scan of the two-pass printing is a staggered pattern shown in FIG. 21A, and the mask for thinning out image data to be printed in the second scan. The pattern is an inverted zigzag pattern shown in FIG. In addition, the recording head has eight ink discharge ports arranged in a line for simplification of description, thinning out four pixels of data every other pixel with a staggered pattern mask, and thinning out with a reversed staggered pattern mask last time. Assume that the data of four pixels are thinned out.
[0038]
Next, the thinned image data is output to the head controller 409, and ink is ejected from the multi-head 410 while the carriage is scanned in the main scanning direction to print an image on the recording material (step S505). The area of the head position and the discharge nozzle in step S505 is the area A in FIG. 1, and the area thinned out by the staggered pattern or the inverted staggered pattern among all the discharge ports is distributed over the entire area for one scan.
[0039]
When printing by ink ejection for one scan is completed, the recording material is transported by a ½ bandwidth of the recording material (step S506). In step S506, the head position is an area B that is advanced by ½ band width from the area A shown in FIG.
[0040]
If printing for one sheet of recording material has not been completed (NO in step S507), the process returns to step S501 to output the next image data transfer request from the interface 404 and newly transferred from an external host device or the like. The incoming image data is written into the band memory 407 under the control of the CPU 401.
[0041]
Thereafter, by repeating the operations from step S501 to step S507, the image data is transferred for all areas as shown in FIGS. 7 and 8, and the two-pass printing operation is completed. Here, FIGS. 7 and 8 are diagrams showing output images when two-pass printing is performed on the recording material.
[0042]
Although not shown, the CPU 401 uses a software interrupt process, a hardware counter, or the like to detect the remaining amount of ink in the ink tank and to perform a head recovery process every time a predetermined amount of ink is consumed. A program for monitoring an operating environment for continuing printing, such as a printing dot count counting process, is executed together with the printing operation program. The CPU 401 first sets a print operation interruption request flag when the print operation needs to be interrupted due to ink supply or head recovery operation.
[0043]
If the CPU 401 determines that the flag for requesting the interruption of the printing operation is set during execution of the two-pass printing from step S501 to step S507 (YES in step S503), the CPU 401 uses the mask pattern selector 406 to perform data The mask pattern for the thinning process is switched (step S508).
[0044]
Here, the mask pattern will be described with reference to FIGS.
[0045]
The multi-pass data processing unit 408 generates thinned image data by masking the image data with the mask pattern shown in FIG. At this time, in the mask pattern selector 406, the mask pattern shown in FIG. Then, in the multi-pass data processing unit 408, the mask pattern of FIG. 15C obtained by multiplying the mask patterns of FIG. 15A and FIG. 15B is used as a mask pattern for the thinning process, and a thinned image is obtained. Data is generated.
[0046]
However, in the mask pattern switching in step S508, the mask pattern shown in FIG. Then, the multi-pass data processing unit 408 uses the pattern shown in FIG. 16C obtained by multiplying the mask pattern shown in FIG. 16A and the mask pattern shown in FIG. 16B as a new mask pattern. This is performed (step S509). Here, the mask pattern in FIG. 16B is a pattern for thinning out image data so as to prohibit the 2/2 pass printing operation of the 2 pass printing by the multi-head 410.
[0047]
Further, the CPU 401 outputs the image data after the thinning process to the head controller 409, and discharges ink from the ink discharge ports of the multi-head 410 to complete the 1/2 pass printing (step S510). This corresponds to prohibiting printing on a new 2/2 pass area and printing a half band which is a 1/2 pass. An image output in this way is shown in FIG. When the second scan printing of the two-pass printing is completed, the printing of the second / second pass image is completed, and the relationship between the head position and the discharge nozzle area at this time becomes the area B in FIG. Only the upper half of the area is printed.
[0048]
Thereafter, the printing operation enters a pause state and shifts to region C in FIG. The CPU 401 resets the print interruption request flag after executing predetermined head recovery processing, ink supply processing, and the like (step S511).
[0049]
When the ink supply process and the head recovery process in step S511 are completed and printing is resumed, the image data for one band is read again from the band memory 407 in FIG. 4 under the control of the CPU 401 (step S512), and the mask pattern In the selector 406, the mask pattern is changed to the pattern shown in FIG. 17B (step S513). The mask pattern in FIG. 17B is a mask pattern inverted so as to complement the mask pattern changed in step S508, and the image data is not subjected to the half-pass printing of the two-pass printing. It is a pattern for thinning out.
[0050]
Next, in the multi-pass data processing unit 408, the mask patterns of FIG. 17A and FIG. 17B are multiplied and the image data is thinned by the new mask pattern of FIG. 17C (step S514). . A head drive signal corresponding to the thinned image data is output to the head controller 409, and a thinned image is output to the recording material by the multi-head 410 (step S515). The relationship between the head position and the discharge nozzle area at this time is as shown by area D in FIG. The head position of the area D and the head position of the area B exist at the same position, but the area of the ink ejection port is the lower half of one band corresponding to the area B and complementary to each other.
[0051]
In step S506, the recording material conveyance operation is performed again, so that the head position becomes the area E in FIG. 1, and then normal two-pass printing is continued.
[0052]
In this way, by completing two-pass printing before and after printing interruption and resumption, density unevenness does not occur between the images of the first pass and the second pass, and the output of the thinned image is output in step S510. The printing operation is interrupted between the carriage scanning operation for the printing operation and the carriage operation in step S515 so that the recording material conveyance operation is not performed, thereby making the joint of the output image inconspicuous. Is possible.
[0053]
When the printing in step S515 is completed, the CPU 401 selects the mask pattern shown in FIG. 15B in the mask pattern selector 406 and uses this mask pattern in order to continuously execute normal two-pass printing. The processes from step S501 to step S507 are sequentially repeated.
[0054]
Next, selection of a mask pattern by the mask pattern selector 406 from immediately before interruption of multi-pass printing to immediately after resumption will be described.
[0055]
FIG. 11 is a diagram showing a mask pattern selected by the mask pattern selector 406 when performing two-pass printing. FIG. 14 is a diagram showing a circuit configuration of the mask pattern selector 406.
[0056]
As shown in FIG. 14, in the case of two-pass printing, the CPU 401 selects a predetermined mask pattern from the mask patterns P1 to P3 (see FIG. 11) of the mask pattern selector 406.
<Mask pattern selection for 2-pass printing>
In FIG. 11, a black area is a print area, and a white area is an area that is not printed by being masked. FIG. 22 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material transport operation when the printing is interrupted and resumed during the two-pass printing operation of FIG.
[0057]
First, a normal two-pass printing operation will be described.
[0058]
As shown in FIG. 22, the mask P1 of FIG. 11 is selected as a mask pattern for limiting the discharge ports of the multi-head 410. Then, the print interruption request flag is monitored (step S1701), an image is output using the mask P1 of FIG. 11 (step S1702), and the recording material is conveyed by ½ band width (step S1703). If the image data has been transferred via the interface 404 (NO in step S1704), the process returns to step S1701, and if the image data transfer via the interface 404 has been completed (YES in step S1704), two-pass printing is performed. End operation.
[0059]
If the CPU 401 determines that the print interruption request flag is set during execution of two-pass printing by repeating steps S1701 to S1704 (YES in step S1701), the mask pattern is switched from the mask P1 to the mask P2 in FIG. Step S1705).
[0060]
Next, an image masked by the mask P2 of FIG. 11 is output with respect to the image data subjected to the thinning process for two-pass printing (step S1706). Then, after step S1706, the recording material conveying operation is not executed, and the printing state is interrupted by the head recovery operation or the like (step S1707). Thereafter, when the two-pass printing operation is resumed, the mask pattern is switched to the mask P3 in FIG. 11 (step S1708), and the image data thinned out for the two-pass printing is masked by the mask P3 in FIG. The processed image is output (step S1709). Next, the mask pattern is switched to the mask P1 in FIG. 11 (step S1710). Then, the recording material is conveyed by ½ band width (step S1703), and normal two-pass printing is continued with the mask pattern of the mask P1.
[0061]
As described above, when the printing operation is interrupted while performing the two-pass printing, the two-pass printing can be performed so that the density unevenness caused by the pause time interval does not occur by once completing the printing operation until the middle. It becomes possible. Further, by selecting a mask pattern so that the recording material conveyance operation is not performed during the printing pause period from the pause to the restart of the printing operation, it is possible to control the feeding image so as not to cause uneven feeding at the joint of the output image. .
[Second Embodiment]
In the first embodiment, the two-pass printing operation has been described as an example of the multi-pass printing operation. However, the present invention can be applied to other numbers of passes (for example, three passes or four passes).
<Mask pattern selection in 3-pass printing part 1>
Therefore, the 3-pass printing operation will be described with reference to FIGS.
[0062]
12 and 13, when the three-pass printing operation is interrupted and resumed, the ink is ejected only from the ink ejection port that scans the area where the three-pass overprinting is not completed, and from the interruption to the restart. FIG. 5 is a diagram showing a mask pattern that does not perform the recording material conveyance operation and the recording material conveyance operation.
[0063]
In the case of three-pass printing, there are two combinations of the ink ejection port capable of ejecting ink by the mask pattern and the transporting operation of the recording material, as shown in FIGS. 12 and 13. As a mask pattern, FIG. And FIG. P1-P 5 and P4 ' The six patterns are appropriately selected and printed.
[0064]
The mask pattern selector 406 selects a predetermined mask pattern from these six patterns, and appropriately executes a recording material conveyance operation with each mask pattern, thereby interrupting and resuming printing without causing time difference unevenness. Is possible.
[0065]
First, a printing operation using the mask pattern of FIG. 12 will be described with reference to FIGS.
[0066]
FIG. 23 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveying operation when printing is interrupted and resumed during the 3-pass printing with the mask pattern of FIG.
[0067]
First, a normal three-pass printing operation will be described.
[0068]
As shown in FIG. 23, the mask P1 in FIG. 12 is selected as a mask for restricting the ink discharge ports of the multi-head 410. Then, the print interruption request flag is monitored (step S1801), an image is output using the mask P1 in FIG. 12 (step S1802), and the recording material is conveyed by 1/3 bandwidth (step S1803). If the image data has been transferred via the interface 404 (NO in step S1804), the process returns to step 1801, and if the image data transfer via the interface 404 has been completed (YES in step S1804), three-pass printing. Ends printing by operation.
[0069]
If the CPU 401 determines that the print interruption request flag is set during execution of 3-pass printing by repeating steps S1801 to S1804 (YES in step S1801), the mask pattern is switched from P1 to P2 in FIG. 12, and 3-pass printing is performed. Therefore, an image masked by the mask P2 in FIG. 12 is output with respect to the image data subjected to the thinning process (step S1805). Here, the recording material is conveyed by 1/3 bandwidth (step S1806).
[0070]
Next, the mask pattern is switched from P2 to P3 in FIG. 12, and an image masked by the mask P3 is output with respect to the image data subjected to the thinning process for three-pass printing (step S1807). Then, after step S1807, the recording material conveyance operation is not executed, and the printing state is interrupted by the head recovery operation or the like (step S1808). Thereafter, the printing operation is resumed. First, the mask pattern is switched from P3 to P4 in FIG. 12, and an image masked by the mask P4 is output with respect to the image data subjected to the thinning process for three-pass printing (step S1809). ). Further, the mask pattern is switched to P5 in FIG. 12, and an image masked by the mask P5 is output with respect to the image data subjected to the thinning process for three-pass printing (step S1810). This completes the third pass in the 3-pass printing. Thereafter, the mask pattern is switched to P1 (step S1811), and normal three-pass printing using the mask P1 is continued. A mask pattern for limiting the ink ejection ports before and after interruption and restart when performing 3-pass printing is selected in the order of P1, P2, P3, P4, P5, and P1.
<Mask pattern selection 2 in 3-pass printing operation>
Next, the printing operation in the pattern of FIG. 13 will be described with reference to FIGS.
[0071]
FIG. 24 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveyance operation when the printing is interrupted and resumed during the execution of the 3-pass printing with the mask pattern of FIG. .
[0072]
First, a normal three-pass printing operation will be described.
[0073]
As shown in FIG. 24, the mask P1 in FIG. 13 is selected in order to limit the ink discharge ports of the multi-head. Then, the print interruption request flag is monitored (step S1901), an image is output using the mask P1 of FIG. 13 (step S1902), and the recording material is conveyed by 1/3 bandwidth (step S1903). If the image data has been transferred via the interface 404 (NO in step S1904), the process returns to step S1901, and if the image data transfer via the interface 404 has been completed (YES in step S1904), 3 Ends printing by pass printing operation.
[0074]
When the CPU 401 determines that the print interruption request flag is set during the execution of three-pass printing by repeating steps S1901 to S1904 (step S1901), the mask pattern is switched from P1 to P2 in FIG. Therefore, an image masked by the mask P2 is output with respect to the image data subjected to the thinning process (step S1905). Next, the mask pattern is changed from P2 to P. 4 The mask P is applied to the image data thinned out for 3-pass printing. 4 The masked image is output (step S1906). Then, after step S1906, the recording material conveyance operation is not executed, and the printing state is interrupted by the head recovery operation or the like (step S1907). Thereafter, the printing operation is resumed. First, the mask pattern is changed to P in FIG. 4 Is switched to P4 ′, and the image data masked by the mask P4 ′ is output with respect to the image data thinned out for the 3-pass printing (step S1908). Here, a recording material having a 1/3 bandwidth is conveyed (step S1909).
[0075]
Next, the mask pattern is switched to P5 in FIG. 13, and the image masked by the mask P5 is output with respect to the image data subjected to the thinning process for three-pass printing (step S1910). This completes the third pass of 3-pass printing. Then, the mask pattern is switched to P1 (step S1911), and normal three-pass printing using the mask P1 is continued. The mask pattern is selected as shown in FIG. 13 by P1 → P2 → P. 4 → P4 ′ → P5 → P1 are selected in this order.
[0076]
As described above, when the mask patterns shown in FIGS. 12 and 13 are used, when the printing operation is interrupted while performing the three-pass printing, the pass printing up to the middle is temporarily completed, whereby the density caused by the pause time interval is obtained. It is possible to complete the 3-pass printing so as not to cause unevenness.
[0077]
In addition, by selecting the mask pattern so that the recording material conveyance operation is not performed during the printing suspension period from the interruption to the resumption of the printing operation, it is possible to control the feeding image so as not to cause uneven feeding at the joint of the output image. Become.
[0078]
The pattern selector 406 is shown in FIGS. 6 A desired mask can be selected from the types of mask patterns.
[Third Embodiment]
Next, a 4-pass printing operation will be described with reference to FIGS.
[0079]
18 to 20 show that when the four-pass printing operation is interrupted, ink is ejected only from an ink ejection port that scans an area where the four-pass printing is not completed, and the recording material is conveyed until the four-pass printing is resumed. It is a figure which shows the mask pattern and recording material conveyance operation | movement which do not perform operation | movement.
[0080]
The mask pattern selector 406 10 By selecting a predetermined mask pattern from the types of mask patterns and appropriately carrying out the recording material conveyance operation for each pattern, printing can be interrupted and resumed without causing time difference unevenness.
<Mask pattern selection in 4-pass printing operation # 1>
Next, a 4-pass printing operation using the mask pattern of FIG. 18 will be described with reference to FIGS.
[0081]
FIG. 25 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material transporting operation when the printing is interrupted and resumed during the 4-pass printing shown in FIG.
[0082]
First, a normal 4-pass printing operation will be described.
[0083]
As shown in FIG. 25, the mask Q1 in FIG. 15 is selected as a mask for restricting the ink discharge ports of the multi-head 410. Then, the print interruption request flag is monitored during the 4-pass printing operation (step S2001), an image is output using the mask Q1 (step S2002), and the recording material is conveyed by ¼ bandwidth (step S2003). ). If the image data has been transferred via the interface 404 (NO in step S2004), the process returns to step 2001. If the image data transfer via the interface 404 has been completed (YES in step S2004), 4 Ends printing by pass printing operation.
[0084]
If the CPU 401 determines that the print interruption request flag has been set during execution of four-pass printing by repeating steps S2001 to S2004 (YES in step S2001), the mask pattern is switched from Q1 to Q2 in FIG. Then, an image masked by the mask Q2 is output with respect to the image data thinned out for the 4-pass printing (step S2005). Here, a recording material having a 1/4 bandwidth is conveyed (step S2006). Further, the mask pattern is switched from Q2 to Q3 in FIG. 18, and an image masked by the mask Q3 is output with respect to the image data subjected to the thinning process for four-pass printing (step S2007). Here, the recording material is conveyed again with a quarter bandwidth (step S2008). Further, the mask pattern is switched from Q3 to Q4 in FIG. 18, and an image masked by the mask Q4 is output with respect to the image data thinned out for four-pass printing (step S2009). Next, the recording material conveyance operation is not executed, and the process shifts to a print interruption state by a head recovery operation or the like (step S2010). Thereafter, the printing operation is resumed. First, the mask pattern is switched to Q5 in FIG. 18, and then the image masked by the mask Q5 is output with respect to the image data subjected to the thinning process for four-pass printing (step S2011). ). Then, the mask pattern is switched to Q6 and a masked image is output (step S2012). Further, the mask pattern is switched from Q6 to Q7, and a masked image is output (step S2013). The process up to this point completes the fourth pass of 4-pass printing.
[0085]
Next, the mask pattern is switched to Q1 (step S2014), and normal four-pass printing using the mask Q1 is continued. As shown in FIG. 18, the mask pattern is selected in the order of Q1, Q2, Q3, Q4, Q5, Q6, Q7, and Q1 to complete four-pass printing.
<Mask pattern selection in 4-pass printing operation # 2>
FIG. 26 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveyance operation when the printing is interrupted and resumed during the 4-pass printing shown in FIG.
[0086]
First, a normal 4-pass printing operation will be described.
[0087]
As shown in FIG. 26, the mask Q1 in FIG. 19 is selected as a mask pattern for limiting the ink discharge ports of the multi-head. Then, the print interruption request flag is monitored (step S2101), an image is output using the mask Q1 of FIG. 19 (step S2102), and the recording material is conveyed by ¼ bandwidth (step S2103). If the image data is transferred via the interface 404 (NO in step S2104), the process returns to step 2101, and if the image data transfer is completed via the interface 404 (YES in step S2104). Printing by the 4-pass printing operation is terminated.
[0088]
If the CPU 401 determines that the print interruption request flag is set during the execution of four-pass printing by repeating steps S2101 to S2104, the mask pattern is switched from Q1 to Q2 in FIG. Then, an image masked by the mask Q2 is output with respect to the image data subjected to the thinning process for four-pass printing (step S2105). Here, the recording material is conveyed by a ¼ bandwidth (step S2106). Next, the mask pattern is switched from Q2 to Q3 in FIG. 19, and an image masked by the mask Q3 is output with respect to the image data thinned out for four-pass printing (step S2107). Further, the mask pattern is changed from Q3 to Q in FIG. 5 The mask Q for the image data thinned out for 4-pass printing. 5 The masked image is output (step S2108). Next, the recording material conveyance operation is not executed, and the print interruption state is made by the head recovery operation or the like (step S2109). Thereafter, the printing operation is resumed. First, the mask pattern is switched to Q5 ′ in FIG. 19, and an image masked by the mask Q5 ′ is output with respect to the image data subjected to thinning processing for four-pass printing (step S2110). ). Then, the mask pattern is switched to Q6 ′ in FIG. 19 and a masked image is output (step S2111). Here, a recording material having a 1/4 bandwidth is conveyed (step S2112). Further, the mask pattern is switched from Q6 ′ to Q7 in FIG. 19 to output a masked image (step S2113). The process up to this point completes the fourth pass of 4-pass printing.
[0089]
Further, switching to the mask Q1 of FIG. 19 (step S2114), the normal four-pass printing operation using the mask Q1 is continued. As shown in FIG. 19, the mask pattern is Q1->Q2->Q3-> Q. 5 → Q5 ′ → Q6 ′ → Q7 → Q1 are selected in this order to complete the 4-pass printing.
<Mask pattern selection in 4-pass printing part 3>
FIG. 27 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveyance operation when the printing is interrupted and resumed during the 4-pass printing of FIG.
[0090]
First, a normal 4-pass printing operation will be described.
[0091]
As shown in FIG. 27, the mask Q1 in FIG. 20 is selected as a mask for restricting the ink discharge ports of the multi-head. Then, the print interruption request flag is monitored (step S2201), an image is output using the mask Q1 of FIG. 20 (step S2202), and the recording material is conveyed by ¼ bandwidth (step S2203). If the image data is transferred via the interface 404 (NO in step S2204), the process returns to step S2201, and if the image data transfer is completed via the interface 404 (YES in step S2204). Printing by the 4-pass printing operation is terminated.
[0092]
If the CPU 401 determines that the print interruption request flag has been set during execution of 4-pass printing by repeating steps S2201 to S2204 (YES in step S2201), the mask pattern is switched from Q1 to Q2 in FIG. Then, the image masked by the mask Q2 is output with respect to the image data subjected to the thinning process for the 4-pass printing (step S2205). Next, without carrying the recording material, the mask pattern is switched from Q2 to Q6 in FIG. 20, and the image masked by the mask Q6 is output with respect to the image data thinned out for four-pass printing ( Step S2206). Further, the mask pattern is switched from Q6 to Q5 ′ in FIG. 20, and an image masked by the mask Q5 ′ is output with respect to the image data subjected to the thinning process for four-pass printing (step S2207). Further, the recording material conveying operation is not executed, and the printing operation is interrupted by the head recovery operation or the like (step S2208). Thereafter, the printing operation is resumed. First, the mask pattern is switched to Q8 in FIG. 20, and an image masked by the mask Q8 is output with respect to the image data subjected to the thinning process for four-pass printing (step S2209). Here, a recording material having a 1/4 bandwidth is conveyed (step S2210). Next, the mask pattern is switched to Q6 ′ in FIG. 20 to output a masked image (step S2211). Here, the recording material having a quarter bandwidth is transported again (step S2212). Further, the mask pattern is switched from Q6 ′ to Q7 in FIG. 20 to output a masked image (step S2213). The process up to this point completes the fourth pass of 4-pass printing.
[0093]
Further, switching to the mask Q1 of FIG. 20 (step S2214), the normal four-pass printing using the mask Q1 is continued. As shown in FIG. 20, the mask pattern is selected in the order of Q1, Q2, Q6, Q5 ', Q8, Q6', Q7, and Q1 to complete four-pass printing.
[0094]
In the above four-pass printing, the pattern selector 406 is shown in FIGS. 10 A desired mask can be selected from the types of mask patterns.
[Other Embodiments]
In the first to third embodiments, with the circuit configuration of FIG. 4, a mask pattern is selected by the mask pattern selector 406, and the first mask pattern for multipass printing is applied to the image data read from the band memory 407. In addition, the ink discharge port is limited by using a new mask pattern obtained by multiplying the second mask pattern for limiting the image recording area in one scan. However, the same effect can be obtained by other methods for limiting the area of the ink discharge port. For example, it can be realized by performing mask processing using the second mask pattern when reading image data from the band memory 407 and outputting it to the multi-pass data processing unit 408. Since the image data for printing for one band is written in the band memory 407, the second mask pattern selected by the mask pattern selector 406 is used as a mask pattern when reading the image data from the band memory 407. This can be realized by performing mask processing and then outputting to the multipath data processing unit 408. The mask process at the time of reading data is a mask process for restricting the nozzle rows of the ink discharge ports. Therefore, in the 2-pass printing, the ink discharge ports are indicated by P1 to P3 in FIG. 13 P1 to P5 and P4 ′, in 4-pass printing, the processing selected by Q1 to Q8, Q5 ′ and Q6 ′ in FIGS. By performing mask processing at the time of data reading using these mask patterns, it becomes possible to designate a nozzle row capable of ejecting ink. Then, by linking the mask pattern selection by the mask pattern selector 406 and the recording material conveyance operation, similarly to the first to third embodiments, the multi-pass printing is paused while suppressing density unevenness and feed unevenness. In addition, the restart operation can be performed.
[0095]
The above embodiments include means (for example, an electrothermal converter, a laser beam, etc.) for generating thermal energy as energy used for performing ink discharge, particularly in the ink jet recording system, By using a system that causes a change in the state of the ink, higher recording density and higher definition can be achieved.
[0096]
As its typical configuration and principle, for example, those performed using the basic principle disclosed in US Pat. Nos. 4,723,129 and 4,740,796 are preferable. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal corresponding to the recording information and applying a rapid temperature rise exceeding the film boiling to the electrothermal transducer, the thermal energy is generated in the electrothermal transducer, and the recording head This is effective because film boiling occurs on the heat acting surface of the liquid, and as a result, bubbles in the liquid (ink) corresponding to the drive signal on a one-to-one basis can be formed. By the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection opening to form at least one droplet. When the drive signal is pulse-shaped, the bubble growth and contraction is performed immediately and appropriately, and thus it is possible to achieve the discharge of liquid (ink) with particularly excellent responsiveness.
[0097]
As this pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further excellent recording can be performed by employing the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface.
[0098]
As the configuration of the recording head, in addition to the combination configuration (straight liquid flow path or right-angle liquid flow path) of the discharge port, the liquid path, and the electrothermal transducer as disclosed in each of the above-mentioned specifications, the heat acting surface The configurations using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region, are also included in the present invention. In addition, Japanese Patent Application Laid-Open No. 59-123670, which discloses a configuration in which a common slot is used as a discharge portion of an electrothermal transducer, or an opening that absorbs a pressure wave of thermal energy is discharged to a plurality of electrothermal transducers. A configuration based on Japanese Patent Laid-Open No. 59-138461 disclosing a configuration corresponding to each part may be adopted.
[0099]
Furthermore, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length is satisfied by a combination of a plurality of recording heads as disclosed in the above specification. Either a configuration or a configuration as a single recording head formed integrally may be used.
[0100]
In addition to the cartridge type recording head in which the ink tank is integrally provided in the recording head itself described in the above embodiment, it is electrically connected to the apparatus main body by being mounted on the apparatus main body. Alternatively, an exchangeable chip type recording head that can supply ink from the apparatus main body may be used.
[0101]
In addition, it is preferable to add recovery means, preliminary means, and the like for the recording head to the configuration of the recording apparatus described above because the recording operation can be further stabilized. Specific examples thereof include a capping unit for the recording head, a cleaning unit, a pressurizing or sucking unit, an electrothermal converter, a heating element different from this, or a preheating unit using a combination thereof. In addition, it is effective to provide a preliminary ejection mode for performing ejection different from recording in order to perform stable recording.
[0102]
Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrated or may be a combination of a plurality of colors. An apparatus having at least one of full colors can also be provided.
[0103]
In the embodiment described above, the description is made on the assumption that the ink is a liquid, but it may be an ink that is solidified at room temperature or lower, or an ink that is softened or liquefied at room temperature, Alternatively, the ink jet method generally controls the temperature of the ink so that the viscosity of the ink is within a stable discharge range by adjusting the temperature within a range of 30 ° C. or higher and 70 ° C. or lower. It is sufficient if the ink sometimes forms a liquid.
[0104]
In addition, it is solidified in a stand-by state in order to actively prevent temperature rise by heat energy as energy for changing the state of ink from the solid state to the liquid state, or to prevent ink evaporation. Ink that is liquefied by heating may be used. In any case, by applying heat energy according to the application of thermal energy according to the recording signal, the ink is liquefied and liquid ink is ejected, or when it reaches the recording medium, it already starts to solidify. The present invention can also be applied to the case of using ink having the property of liquefying for the first time. In such a case, the ink is held as a liquid or solid in a porous sheet recess or through-hole as described in JP-A-54-56847 or JP-A-60-71260, It is good also as a form which opposes with respect to an electrothermal converter. In the present invention, the most effective one for each of the above-described inks is to execute the above-described film boiling method.
[0105]
In addition, as a form of the recording apparatus according to the present invention, a copying apparatus combined with a reader or the like, and a transmission / reception function are provided as an image output terminal of an information processing apparatus such as a computer or the like. It may take the form of a facsimile machine.
[Other Embodiments]
Note that the present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, and a printer), and a device (for example, a copying machine and a facsimile device) including a single device. You may apply to.
[0106]
Another object of the present invention is to supply a storage medium storing software program codes for implementing the functions of the above-described embodiments to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus stores the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in the.
[0107]
In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.
[0108]
As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.
[0109]
Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.
[0110]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.
[0111]
When the present invention is applied to the above-mentioned storage medium, the program code corresponding to the above-described flowchart is stored in the storage medium. In brief, each module shown in the memory map example of FIG. Is stored in a storage medium.
That is, at least “a thinned image module for forming a thinned image in each scan using the first mask pattern” and “second image so that the recording operation of the pass in which image recording is not completed when the recording operation is interrupted” is completed. The program code of each module corresponding to “a mask pattern selection module for selecting a mask pattern” and “a recording module for recording an image by multiplying a first mask pattern by a second mask pattern” is stored in a storage medium. That's fine.
[0112]
【The invention's effect】
As described above, according to the present invention, when the recording operation is interrupted, the image output by selecting the second mask pattern so as to complete the recording operation of the pass where the image recording is not completed is output. Density unevenness (time difference unevenness) due to the print pause period does not occur in the data, and even when ink supply processing or head recovery processing is performed for a long time, it is possible to record an image without print unevenness.
[0113]
Also, when resuming the recording operation, since the ink ejection port mask is selected so that the recording operation can be resumed without conveying the recording material, there is no unevenness in feeding due to the recording material conveying operation, The joint between the images before and after the resumption of the recording operation becomes inconspicuous.
[0114]
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a change in a head position and an ink discharge port when a two-pass printing operation is paused and resumed.
FIG. 2 is a perspective view showing a schematic configuration of a conventional image recording apparatus.
FIG. 3 is a block diagram illustrating a general inkjet image recording apparatus.
FIG. 4 is a schematic block diagram of an image recording apparatus according to an embodiment of the present invention.
FIG. 5 is a flowchart showing a control operation of a CPU 401.
FIG. 6 is a diagram illustrating a head position and a recorded image at the time of multi-pass printing set to two passes.
FIG. 7 is a diagram illustrating an output image when two-pass printing is performed on a recording material.
FIG. 8 is a diagram illustrating an output image when two-pass printing is performed on a recording material.
FIG. 9 is a diagram illustrating a case where the time interval between the first pass and the second pass is short.
FIG. 10 is a diagram illustrating a case where the time interval between the first pass and the second pass is long.
FIG. 11 is a diagram showing a mask pattern selected by a mask pattern selector 406 when performing two-pass printing.
FIG. 12 is a diagram illustrating a mask pattern and a recording material conveyance operation when a three-pass printing operation is interrupted and resumed.
FIG. 13 is a diagram illustrating a mask pattern and a recording material conveyance operation when a three-pass printing operation is interrupted and resumed.
14 is a diagram showing a circuit configuration of a mask pattern selector 406. FIG.
FIG. 15 is a diagram showing a mask pattern used for two-pass printing.
FIG. 16 is a diagram showing a mask pattern used for two-pass printing.
FIG. 17 is a diagram showing a mask pattern used for two-pass printing.
FIG. 18 is a diagram illustrating a mask pattern and a recording material conveyance operation when a four-pass printing operation is interrupted.
FIG. 19 is a diagram illustrating a mask pattern and a recording material conveyance operation when a four-pass printing operation is interrupted.
FIG. 20 is a diagram illustrating a mask pattern and a recording material conveyance operation when a four-pass printing operation is interrupted.
FIG. 21 is a diagram showing staggered and inverted staggered mask patterns used in a two-pass printing operation.
22 is a flowchart showing a cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveying operation when the printing is interrupted and resumed during the two-pass printing operation of FIG.
23 is a flowchart showing a cooperative operation of mask pattern selection by a mask pattern selector 406 and recording material conveyance operation when printing is interrupted and resumed during three-pass printing with the mask pattern of FIG.
24 is a flowchart showing a cooperative operation of mask pattern selection by the mask pattern selector 406 and recording material conveyance operation when printing is interrupted and resumed during execution of the 3-pass printing with the mask pattern of FIG. .
FIG. 25 is a flowchart showing the cooperative operation of the mask pattern selection by the mask pattern selector 406 and the recording material conveyance operation when the printing is interrupted and resumed during the 4-pass printing shown in FIG.
26 is a flowchart showing a cooperative operation of mask pattern selection by a mask pattern selector 406 and a recording material transport operation when printing is interrupted and resumed during execution of the 4-pass printing of FIG.
27 is a flowchart showing a cooperative operation of mask pattern selection by a mask pattern selector 406 and a recording material transport operation when printing is interrupted and resumed during execution of the 4-pass printing of FIG.
FIG. 28 is a diagram showing an example of a memory map when the program module of the present invention is stored in a storage medium.
[Explanation of symbols]
401 CPU
402 ROM
403 RAM
404 interface
405 Operation / display section
406 Mask pattern selector
407 band memory
408 Multipath data processing unit
409 head controller
410 Multihead
801 ink drops

Claims (1)

In an image recording apparatus for recording an image by causing a head including a plurality of ink ejection openings to scan a unit recording area of a recording material three times,
Conveying means for conveying the recording material;
A pattern selector for selecting a second mask pattern for determining an ink discharge port used for recording in each scan;
Based on the second mask pattern and the first mask pattern for dividing the image data to be recorded in the unit recording area into the three scans, the image data is thinned out, and the thinned image data of each scan is obtained. Generating means for generating;
Control means for executing recording before and after resuming recording based on the thinned image data by controlling the conveying means, the pattern selector, and the head;
The control means includes
(A) The recording material is conveyed between two scans immediately before the interruption of recording, the conveying means is controlled so as not to convey the recording material between the two scans immediately after resumption of recording, and recording is performed. The second mask pattern is selected so that different ink ejection port groups are used in the two scans immediately before the recording interruption for the unit recording area where the recording is completed immediately before the interruption, and the recording is started immediately after resuming the recording. By controlling the pattern selector so as to select the second mask pattern so that the same ink ejection port group is used in two scans immediately after the recording is resumed with respect to the unit recording area, before the recording is interrupted and the recording is resumed. A first recording operation for performing a later recording;
(B) controlling the conveying means to convey the recording material between two scans immediately after resuming recording without conveying the recording material between two scannings immediately before the interruption of recording; and The second mask pattern is selected so that the same ink discharge port group is used in the two scans immediately before the recording interruption for the unit recording area where the recording is completed immediately before the recording interruption, and the recording starts immediately after the recording is resumed. By controlling the pattern selector so as to select the second mask pattern so as to use different ink ejection port groups in the two scans immediately after resuming the recording for the unit recording area to be performed, the recording before the recording interruption and the recording An image recording apparatus capable of selectively executing a second recording operation for executing recording after resumption.

Images