JP2002144539A - Ink jet recording method and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce unevenness of density caused by the difference of recording time required for each recording head to eject ink when recording is performed in multipath using a plurality of recording heads. SOLUTION: When ink is ejected to a first area (A) and a second area (B) adjacent on a recording medium while dividing into a plurality of times, respectively, by performing main scanning relatively using an ink ejecting part, ink is ejected such that the quantity of ink being ejected per unit area for the first area in preceding main scanning is different from the quantity of ink being ejected per unit area for the second area in preceding main scanning if T1≠T1, where T1 is the time difference between last recording in the first area with a recording head 601 and first recording with a recording head 602, and T2 is the time difference between last recording in the second area with the recording head 601 and first recording with the recording head 602.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus and an ink jet recording method for performing recording by discharging ink from at least two recording heads, and an object thereof is to reduce density unevenness.

[0002]

2. Description of the Related Art Recording devices used as printing means for images and the like in printers, copiers, facsimile machines and the like, or recording devices used as print output devices such as composite electronic devices and workstations including computers and word processors, etc. It is configured to record an image or the like on a recording material (hereinafter, also referred to as a recording medium) such as a sheet or a plastic thin plate based on information (including all output information such as character information). Such a recording apparatus, depending on the recording method, an inkjet method,
The method can be classified into a wire dot method, a thermal method, a laser beam method, and the like. Among them, an ink jet recording apparatus (hereinafter referred to as an ink jet recording apparatus)
Is to perform recording by ejecting ink from a recording means including a recording head to a recording material, and it is easy to achieve high definition compared to other recording methods, and is high speed, excellent in quietness, and inexpensive. It has various advantages. On the other hand, in recent years, the importance of color output of color images and the like has increased, and many color inkjet recording apparatuses of high image quality comparable to silver halide photography have been developed.

In such an ink jet recording apparatus, a recording head in which a plurality of recording elements are integrated and arrayed is used in order to improve the recording speed. Generally, a plurality of recording heads are provided.

FIG. 1 shows a configuration of a main part of an apparatus for performing recording (hereinafter, also simply referred to as printing) on paper using the recording head. In FIG. 1, reference numeral 101 denotes an ink jet cartridge. These are composed of ink tanks storing four color inks, that is, black, cyan, magenta, and yellow inks, and a recording head 102 corresponding to each ink. The discharge ports provided on the print heads have N per inch on each print head 102.
N nozzles are arranged at a pixel density (Ndpi). Reference numeral 103 denotes a paper feed roller, which rotates in the direction of the arrow in the figure while holding the print paper P together with the auxiliary roller 104, and conveys the print paper P in the y direction as needed. A pair of paper feed rollers 105 feeds print paper. Like the rollers 103 and 104, the pair of rollers 105 rotate while sandwiching the printing paper P, but tension can be applied to the printing paper by reducing the rotation speed of the paper feeding roller 103. Reference numeral 106 denotes a carriage that supports the four ink jet cartridges 101 and causes them to be scanned together with printing. The carriage 106 waits at a home position h at a position indicated by a broken line in the drawing when printing is not being performed or when performing a recovery process of the recording head 102 or the like.

When the print start command is issued, the carriage 106 at the home position h before the start of printing is moved in the x direction, and is moved by the n nozzles 201 arranged at a density of N nozzles per inch of the recording head 102. Then, printing is performed on the paper surface with a width of n / N inches. When printing to the end of the paper surface is completed, the carriage returns to the original home position, and moves again for printing in the x direction. Before the second printing after the first printing is completed, the paper feeding roller 103 rotates in the direction of the arrow to feed the paper in the y direction by the width of n / N inches. In this manner, the width n /
By repeatedly performing N inch printing and paper feeding, for example, printing for one page can be completed. Note that such a print mode is hereinafter referred to as a one-pass print mode.

[0006] Another print mode is a multi-pass print mode. The multi-pass print mode is a print mode in which printing is completed by recording a print area in a plurality of times. The multi-pass print mode will be described in detail. When a print start command is issued, the carriage 106 at the home position h before the start of printing moves in the x direction, and moves on the paper by n nozzles arranged at a density of N nozzles per inch of the recording head 102. Width n / N
Prints inches. If the same area is to be recorded M times, the dots printed by scanning at this time are obtained by thinning specified image data to 1 / M in a predetermined pattern. When printing to the end of the paper surface is completed, the carriage returns to the original home position and moves again for printing in the x direction. Before the second printing starts after the first printing is completed, the paper feeding roller 103 rotates in the direction of the arrow to feed the paper in the y-direction by a width of n / (M × N) inches. Then, in the M-th scan, printing is performed in accordance with each mask pattern, thereby completing printing in an area corresponding to each nozzle. Hereinafter, a multi-pass print mode in which the same print area is printed in M main scans (scans) by the print head will be referred to as M print mode.
Also called pass printing mode.

FIG. 2 shows a two-pass mask pattern used in the two-pass print mode.

In FIG. 2, reference numeral 201 denotes a first pass mask pattern, and reference numeral 202 denotes a second pass mask pattern.

Each of the 4 × 4 print masks determines a pixel to be printed by superimposing a black print pixel with image data in each pass, and prints each pass. The mask pattern 201 of the first pass and the mask pattern 202 of the second pass are mask patterns having a print density of 50% in a staggered arrangement and an inverted staggered arrangement, respectively. 202 are in an interpolation relationship. In addition to the mask pattern shown in FIG. 2, a mask pattern in which the print density in each pass is １ ／ is usually used for both the one-pass and two-pass mask patterns.

[0010]

However, in a multi-pass print mode using two or more print heads, a print having a different time difference from the completion of printing of the first print head to the start of printing of the second print head. If the areas are mixed in the printed image, a difference occurs between the degree of bleeding of the ink and the degree of bleeding of the ink, resulting in visually unevenness.

Hereinafter, from the completion of printing by the first recording head,
A process in which a print area in which a time difference occurs until the second recording head starts printing is mixed in a print image will be described.

FIG. 3 is a schematic diagram of a nozzle arrangement using two recording heads.

In FIG. 3, reference numeral 301 denotes a first recording head, and 302 denotes a second recording head. Reference numeral 303 denotes a nozzle. In each recording head, n nozzles are arranged at intervals of N dpi in the y direction (paper feed direction). The first recording head 301 and the second recording head 302 are separated by G / N inch in the y direction.

FIG. 4 shows a schematic diagram of the two-pass print mode in the case of using FIG. Here, for example, the second recording head is a head for discharging black ink, and the second recording head is a head for discharging color ink other than black.

In FIG. 4, reference numerals 301 and 302 denote first and second recording heads as in FIG.

1 and 3, the y direction indicates the paper feed direction, and the t direction is an axis indicating the elapsed time of printing.
Each time interval from the scan to the fifth scan is equal to T. A and B are (n−
2G) / 2N inch and G / N inch distance printing area. That is, the length of the print area A + B in the y direction is equal to half the length of the nozzle.

In the first scan, the first recording head 301 prints the print area A + B with the mask pattern 201 of the first pass having a print density of 1/2. After that, the printing paper is
A + B transport in the direction.

In the second scan, the first recording head 301 moves the print area A + B to the print mask 202 of the second pass.
To complete the image by the first recording head. Thereafter, the printing paper is transported in the y direction by a distance A + B.

In the third scan, the second recording head 302 is at a distance G / N in from the first recording head 301.
With ch, printing is performed only in the printing area A without reaching the printing area B. The mask pattern used at this time is the mask pattern 201 of the first pass having a print density of ２.
Thereafter, the printing paper is transported in the y direction by a distance A + B.

In the fourth scan, the second recording head 3
02 designates the print area A as the mask pattern 202 of the second pass.
And printing is performed in the print area B using the mask pattern 201 of the first pass. Thereafter, the printing paper is transported in the y direction by a distance A + B.

In the fifth scan, the second recording head 3
02 prints the print area B using the mask pattern 202 of the second pass, and all prints in the print areas A and B are completed.

From the above process, in the print area A, the time T after the printing by the first recording head 301 is completed.
It can be seen that the printing by the second recording head 302 is started later, while the printing in the printing area B starts after the time 2T.

As described above, print areas having different time differences from the completion of printing by the first recording head 301 to the start of printing by the second recording head 302 are mixed in the printed image. As a result, it was found that the degree of bleeding of the first ink type ejected from the first recording head 301 was different, and a density difference occurred between the print areas A and B.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to reduce the occurrence of density unevenness due to a printing time difference in an ink jet printing apparatus having at least two printing heads in a multi-pass printing mode. Another object of the present invention is to provide an ink jet recording method and apparatus capable of performing good image recording.

[0025]

According to the present invention, which solves the above-mentioned problems, an ink ejection section is relatively divided into a plurality of times for a first area and a second area adjacent to each other on a recording medium. An ink jet recording apparatus for performing recording by discharging ink while scanning, comprising a driving unit for the ink discharging unit, wherein the driving unit is configured to drive a main unit ahead of the ink discharging unit when recording the first area. The time difference between the time when the ink is ejected in the scan and the time when the ink is ejected in the subsequent main scan is T1 and the time when the ink is ejected in the preceding main scan of the ink ejecting unit when the second area is recorded. When T1 差 T2 when the time difference from when the ink is ejected in the subsequent main scan is T2, the first time
The ink ejection unit is configured such that the amount of ink per unit area ejected in the main scan preceding the region is different from the amount of ink per unit area ejected in the main scan preceding the second region. An ink jet recording apparatus characterized by being driven.

Further, according to the present invention, ink is ejected to the adjacent first area and second area on the recording medium while the ink ejection section is relatively main-scanned a plurality of times. An ink jet recording method for performing recording, wherein a time difference between the time when ink is ejected in a preceding main scan of the ink ejection unit and the time when ink is ejected in a subsequent main scan is T1 when recording the first area. And
When recording the second area, the time difference between the time when the ink is ejected in the preceding main scan of the ink ejection unit and the time when the ink is ejected in the subsequent main scan is T2.
When ≠ T2, the amount of ink per unit area ejected in the main scan preceding the first area and the amount of ink per unit area ejected in the main scan preceding the second area The ink jet recording method is characterized in that the ink ejecting unit is driven so as to eject ink so as to differ from each other.

[0027]

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

FIG. 5 is a block diagram showing a control configuration of the ink jet recording apparatus according to one embodiment of the present invention.
The mechanical configuration of the ink jet recording apparatus according to the present embodiment is the same as that shown in FIG.

Referring to FIG. 5, a CPU 500 controls each unit of the apparatus and executes data processing via a main bus line 505. That is, the CPU 500 stores in the ROM 501
The data processing, head driving, and carriage driving described in FIG. The RAM 502 is the CPU 50
0 is used as a work area for data processing etc.
In addition, these memories include a hard disk and the like. The image input unit 503 has an interface with the host device, and temporarily holds an image input from the host device. The image signal processing unit 504 executes data processing shown in FIG. 5 and subsequent figures in addition to color conversion and binarization.

The operation unit 506 includes keys and the like, thereby enabling control input and the like by the operator. The recovery system control circuit 507 controls a recovery operation such as preliminary ejection according to a recovery processing program stored in the RAM 502. That is, the recovery motor 508 drives the recording head 513, the cleaning blade 509, the cap 510, and the suction pump 511 that are opposed to and separate from the recording head 513. Further, the head drive control circuit 515 controls the driving of the ink ejection electrothermal transducer of the recording head 513, and usually causes the recording head 513 to perform preliminary ejection and ink ejection for recording. Further, the carriage drive control circuit 516 and the paper feed control circuit 517 similarly control the movement of the carriage and the paper feed according to the program.

The recording head 513 has a substrate provided with an electrothermal converter for applying thermal energy to the ink and causing the ink to be ejected. The substrate is provided with a heat retaining heater. The ink temperature can be adjusted by heating to a desired set temperature. Also, the thermistor 512
Similarly, it is provided on the substrate, and is used to measure a substantial ink temperature inside the print head.
Similarly, the thermistor 512 may be provided outside, not on the substrate, or may be near the periphery of the recording head. In addition to the above, the recording head 513 may be a person who ejects ink using a piezo element.

Some embodiments of the present invention based on the above-described apparatus configuration will be described below.

(Embodiment 1) FIG. 6 is a schematic view of a recording head used in this embodiment.

In FIG. 6, reference numeral 601 denotes a black recording head;
02 represents a color recording head.

Both the black and color recording heads have a density of N = 600 pieces per inch (600 dpi), and the black recording head 601 has n = 320 discharge ports (320 nozzles) and the color recording head 602 has n = 320 nozzles. There are 128 discharge ports (128 nozzles).

The black recording head 601 prints using all 320 nozzles in the black recording mode, but uses 128 nozzles from the head (upper end in the figure) in the color recording mode.

The positional relationship between the black recording head 601 and the color recording head 602 is as follows.
Is located at a position shifted in the Y direction by 144 nozzles. That is,
It can be seen that the black recording head 601 and the color recording head 602 used in the color mode have a gap of 16 nozzles in the Y direction. The recording head has a cyan recording head, a magenta recording head, and a yellow recording head, and is arranged side by side in the X direction.

The paper feed conveyance amount for conveying the recording medium in the two-pass print mode is 1/128 of 128 nozzles per scan.
The recording medium may be sequentially conveyed in the sub-scanning direction by a recording width of 2, that is, 64 nozzles (2.71 mm).

However, as described above, there is a gap of 16 nozzles between the used nozzles of the black recording head 601 used in the color mode and the used nozzles of the color recording head 602, and the printing of the black recording head 601 is performed. Are completed, and areas having different time differences from the start of printing by the color recording head 602 are mixed, resulting in uneven density.

Therefore, in the present embodiment, a mask pattern shown in FIG. 7 is used instead of a mask pattern which is usually used, that is, a mask pattern having a pass print density of 50%.

In FIG. 7, reference numeral 701 denotes a mask pattern having a size of 4 × 4 and a print density (recording density) of 75%.
Reference numeral 2 denotes a mask pattern having a size of 4 × 4 and a print density of 25%. Further, the mask patterns of the mask patterns 701 and 702 are both in an interpolation relationship.

FIG. 8 is a schematic diagram illustrating a printing method using mask patterns 701 and 702 according to the present embodiment when areas having different time differences are mixed.

In FIG. 8, reference numerals 601 and 602 denote black and color recording heads. Since the color recording heads are arranged side by side for cyan, magenta, and yellow, the printing time difference from the black recording head is the same. Therefore, it is illustrated as one recording head for convenience. Each time interval from the first scan to the fifth scan in the drawing is equal to T. A and B are 48 in the y direction, respectively.
This represents the print area at a distance of nozzles and 16 nozzles. That is, the length of the print area A + B in the y direction is half the length of the nozzle, that is, equal to the length of 64 nozzles.

In the first scan, the black recording head 6
01 prints the print area A with the 75% mask pattern 701 and the print area B with the 25% mask pattern 702. Thereafter, the printing paper is transported in the y direction for a distance of 64 nozzles.

In the second scan, the black recording head 6
01 prints the print area A using the 25% mask pattern 702 and the print area B using the 75% mask pattern 701;
Complete the black ink image. Thereafter, the printing paper is transported in the y direction for a distance of 64 nozzles.

In the third scan, the color recording head 602 does not reach the printing area B due to a gap of 16 nozzles with the black recording head 601, and only the printing area A is printed using the 25% mask pattern 702. I do. Thereafter, the printing paper is transported in the y direction for a distance of 64 nozzles.

In the fourth scan, the color recording head 602 sets the print areas A and B in the 75% mask pattern 7.
01 is used for printing. Thereafter, the printing paper is moved 64 times in the y direction.
It is transported by the distance of the nozzle.

At the fifth scan, the color recording head 601 performs printing on the print area B using the 25% mask pattern 702, and complete printing of the print areas A and B is completed.

From the above process, in the printing area A,
Printing by the 25% mask pattern 702 of the black recording head 601 in the second scan, and 25% mask pattern 702 of the color recording head 602 in the third scan
, The bleeding of the black ink is suppressed as compared with the printing using the normal 50% mask pattern. This is because the recording is performed at the printing density of 25% instead of the normal 50% in the second scan, so that the amount of ink applied per unit area is reduced, and the time interval between the second scan and the third scan is only T. This is because, even when there is no color ink, the black ink applied in the second scan has already been fixed at the time when the color ink is applied in the third scan. In the print area B, a normal 50% mask is printed by the 75% mask pattern 701 of the black print head 601 in the second scan and the 75% mask pattern 701 of the color print head 602 in the fourth scan. Black ink will bleed more than printed by a pattern. That is, the time interval between the second scan and the fourth scan is 2
Even if the interval is as long as T, the amount of ink applied per unit area is large, so that the recording density of the print area A recorded in the above-described second scan and third scan can be made equal.

By using the mask pattern as described above, the black ink in the print area A and the black ink in the print area B are spread to the same extent, thereby reducing the density unevenness.

Further, the present invention is not limited to the mask pattern having the printing density as described above, but includes the type of ink, black ink,
A mask pattern having an appropriate printing density may be selected depending on the physical properties of the color ink and the type of recording medium.

(Second Embodiment) In the first embodiment, the case of the two-pass print mode is used. In the present embodiment, the present invention is applied to the case of the three-pass print mode.

The recording head used in this embodiment is the same as in the first embodiment.

The black print head 601 prints using all 320 nozzles in the black print mode, but in the color three-pass print mode, both the black and color print heads start from the top (upper end in the figure). 126 nozzles are used.

The paper transport amount for transporting the recording medium in the 3-pass print mode is 1/126 nozzles per scan.
3, the recording medium may be conveyed in the sub-scanning direction by a recording width of 42 nozzles (1.78 mm).

However, as in the two-pass print mode, there is a gap between the used nozzles of the black print head 601 and the used nozzles of the color print head 602 used in the color mode, resulting in a gap of 18 nozzles in the number of nozzles. . As in the first embodiment, the gap causes uneven density.

However, in this embodiment, the mask pattern usually used, that is, each pass print density 1
The mask pattern shown in FIG. 9 is used instead of the mask pattern of / 3.

In FIG. 9, reference numeral 901 denotes a mask pattern having a size of 6 × 6 and a printing density of 1/6,
× 6, a mask pattern with a printing density of ３, and 903 a mask pattern with a size of 6 × 6 and a printing density of ２. The mask patterns of the mask patterns 901, 902 and 903 are in an interpolating relationship.

Referring to FIG. 10, a schematic diagram showing a printing method using mask patterns 901, 902, and 903 in the present embodiment when regions having different time differences are mixed will be described.

In FIG. 10, reference numerals 1001 and 1002 denote black and color recording heads. As in the first embodiment,
The color recording head is illustrated as one recording head for convenience. Each time interval from the first scan to the seventh scan in the drawing is equal to T. A and B represent print areas at a distance of 26 nozzles and 16 nozzles in the y direction, respectively. That is, the length of the print area A + B in the y direction is equal to 1/3 of the nozzle length, that is, 42 nozzles.

In the first scan, the black recording head 1
001 prints the print area A with the 1/2 mask pattern 903 and print area B with the 1/6 mask pattern 901.
Thereafter, the printing paper is transported in the y direction for a distance of 42 nozzles.

In the second scan, the black recording head 1
001 designates the print areas A and B as 1/3 mask patterns 90
Print using 2. Thereafter, the printing paper is transported in the y direction for a distance of 42 nozzles.

In the third scan, the black recording head 1
001 prints the print area A with the 1/6 mask pattern 901 and prints the print area B with the 1/2 mask pattern 903 to complete the black ink printing. After that, the printing paper is
It is conveyed in the direction by a distance of 42 nozzles.

In the fourth scan, the color recording head 1002 does not reach the printing area B due to the gap of 18 nozzles with the black recording head 1001, and the printing area A
Only printing is performed using the 1/6 mask pattern 901. Thereafter, the printing paper is transported in the y direction for a distance of 42 nozzles.

In the fifth scan, the color recording head 1002 sets the print area A to the 1/3 mask pattern 90
2. Printing is performed on the print area B using the 1/2 mask pattern 903. Thereafter, the printing paper is transported in the y direction for a distance of 42 nozzles.

At the sixth scan, the color recording head 1002 sets the print area A to the half mask pattern 90.
3. Printing is performed on the print area B using the 1/3 mask pattern 902. Thereafter, the printing paper is transported in the y direction for a distance of 42 nozzles.

At the seventh scan, the color recording head 1002 sets the print area B to 1/6 mask pattern 901
Is used to complete printing of all images.

From the above process, in the print area A,
1/6 of black recording head 1001 at third scan
Printing by the mask pattern 901 and 1/6 mask pattern 9 of the fourth recording color print head 1002
By printing with 01, blurring of black ink is suppressed as compared with printing with a normal 1/3 mask pattern. Further, in the printing area B, the normal printing is performed by printing with the half mask pattern 903 of the black recording head 1001 in the third scan and printing with the half mask pattern 903 of the color recording head 1002 in the fifth scan. The black ink is more blurred than printed by the / 3 mask pattern.

By using the mask pattern as described above, the black ink in the print area A and the black ink in the print area B are blurred to the same extent, thereby eliminating the density unevenness.

Further, the present invention is not limited to the mask pattern of the printing density as described above, but includes the type of ink, black ink,
A mask pattern having an appropriate printing density may be selected depending on the physical properties of the color ink and the type of recording medium.

(Embodiment 3) In the first and second embodiments, 100% of the print dots are printed for the print data.
The present invention is applied to a case where% print dots are printed using a print mask. In the present embodiment, a three-pass print mode will be described.

The recording head used in this embodiment is the same as in the second embodiment.

FIG. 11 shows a print mask used in the present embodiment.

In FIG. 11, 1101 has a size of 6 ×
6, a mask pattern with a printing density of 1/3, 1102
Is a mask pattern of size 6 × 6, print density 2/3, 1
Reference numeral 102 denotes a mask pattern having a size of 6 × 6 and a print density of 100%. Also, the mask patterns 1101 and 1102
And the mask pattern of 1103 are 2 for the print data.
This is a mask pattern that can print 00%.

The printing process in the present embodiment is the same as that in the second embodiment. In the second embodiment, the 1/3 mask pattern 1101 is used instead of the 1/6 mask pattern 901, and the 2/3 mask pattern is used instead of the 1/3 mask pattern 902. 3 mask pattern 110
A 100% mask pattern 1103 is used instead of the 1/2 mask pattern 903.

From the printing process of the second embodiment and the mask pattern shown in FIG. 11 used in the present embodiment, in the printing area A, the black recording head 1 in the third scan is used.
001 printing by the 1/3 mask pattern 1101 and 1/3 of the fourth scan color recording head 1002
The printing by the mask pattern 1101 suppresses the bleeding of the black ink compared to the printing by the normally used 2/3 mask pattern. In the print area B, printing is performed by the 100% mask pattern 1103 of the black print head in the third scan, and 100% mask pattern 1103 of the color print head 1002 in the fifth scan.
, The black ink becomes more blurred than the normal ／ mask pattern.

By using the mask pattern as described above, the black ink in the print area A and the black ink in the print area B are spread to the same extent, thereby reducing the density unevenness.

[0078]

As described above, according to the present invention,
It is possible to provide an ink jet recording apparatus capable of preventing the occurrence of density unevenness due to a printing time difference of an ink jet recording apparatus having at least two recording heads in a multi-pass print mode and performing good image recording.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a main part of a recording apparatus using a recording head.

FIG. 2 is a diagram showing a two-pass mask pattern.

FIG. 3 is a schematic diagram showing a nozzle arrangement using two recording heads.

FIG. 4 is a schematic diagram of a two-pass print mode when the recording head shown in FIG. 2 is used.

FIG. 5 is a block diagram illustrating a control configuration of the inkjet recording apparatus.

FIG. 6 is a schematic diagram showing a recording head used in the first embodiment.

FIG. 7 is a diagram showing a mask pattern used in the first embodiment.

FIG. 8 is a schematic diagram for explaining a printing method according to the first embodiment.

FIG. 9 is a diagram showing a mask pattern used in the second embodiment.

FIG. 10 is a schematic diagram illustrating a printing method according to a second embodiment.

FIG. 11 is a diagram showing a mask pattern used in a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Ink-jet cartridge 102 Recording head 103 Paper feed roller 104 Auxiliary roller 105 Paper feed roller 106 Carriage 201 Mask pattern of the 1st pass 202 Mask pattern of the 2nd pass 301 First printhead 302 Second printhead 303 Nozzle 500 CPU 501 ROM 502 RAM 503 Image input unit 504 Image signal processing unit 505 Main bus line 506 Operation unit 507 Recovery system control circuit 508 Recovery system motor 509 Cleaning blade 510 Cap 511 Suction pump 512 Thermistor 513 Recording head 514 Head temperature control circuit 515 Head drive control Circuit 516 Carriage drive circuit 517 Paper feed control circuit 601, 1001 Black printhead 602 1002 Color printhead 701 Mark Mask pattern of 75% density 702 Mask pattern of 25% print density 901 Mask pattern of 1/6 print density 902 Mask pattern of 1/3 print density 903 Mask pattern of 1/2 print density 1101 Mask pattern of 1/3 print density 1102 mask pattern with 2/3 printing density 1103 mask pattern with 100% printing density

Continued on the front page (72) Inventor Jiro Moriyama 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2C056 EA06 EC70 EC74 ED05 EE15 FA03 FA11

Claims (20)

[Claims] A first area and a second area adjacent to each other on a recording medium;
An ink jet recording apparatus that performs recording by ejecting ink while relatively performing main scanning relative to the ink ejection unit in a plurality of times for each of the regions, comprising: a driving unit for the ink ejection unit; Means for recording the first area, wherein the time difference from when the ink is ejected in the preceding main scan of the ink ejection unit to when the ink is ejected in the subsequent main scan is T
T1 ≠ 1 and the time difference between the time when the ink is ejected in the preceding main scan of the ink ejection unit and the time when the ink is ejected in the succeeding main scan is T2 when recording the second area. When T2, the amount of ink per unit area ejected in the main scan preceding the first area and the amount of ink per unit area ejected in the main scan preceding the second area are equal to each other. An ink jet recording apparatus characterized in that the ink ejection unit is driven differently. 2. The ink ejection section includes at least a first ink ejection section and a second ink ejection section, and the time difference T1 is such that ink is ejected from the first ink ejection section in a preceding main scan. The time difference T2 is a time difference from when the ink is ejected from the first ink ejection portion in the preceding main scan to the time when the ink is ejected from the second ink ejection portion in the subsequent main scan. 2. The ink jet recording apparatus according to claim 1, wherein the time difference is a time difference between the time when the ink is ejected from the second ink ejection unit in a subsequent main scan. 3. When T1 ≠ T2, a mask pattern used to discharge ink in the main scan preceding the first area and ink in the main scan preceding the second area. By differentiating the mask pattern used for discharging the first area, the amount of ink per unit area ejected in the main scan preceding the first area and the amount of the ink per unit area ejected in the main scan preceding the second area. 2. The method according to claim 1, wherein an amount of ink ejected per unit area is made different.
Or the inkjet recording apparatus according to 2. 4. The ink jet recording apparatus according to claim 2, wherein the ink ejected by said first ink ejecting section is different from the ink ejected by said second ink ejecting section. 5. The ink jet recording apparatus according to claim 4, wherein the ink ejected by said first ink ejecting section has a different color from the ink ejected by said second ink ejecting section. 6. The ink jet recording apparatus according to claim 4, wherein the ink ejected by said first ink ejection section has a different surface tension from the ink ejected by said second ink ejection section. 7. The method according to claim 5, wherein the ink ejected by the first ink ejection unit is a black ink, and the ink ejected by the second ink ejection unit is a color ink other than black. Inkjet recording device. 8. The method according to claim 1, wherein the number of times of main scanning is M,
<T2, a mask pattern used to eject ink in the last main scan of the first ink ejection unit before the second ink ejection unit starts printing on the first area. 4. The ink jet recording apparatus according to claim 3, wherein a density at which the ink is ejected is less than 1 / M. 9. The method according to claim 1, wherein the number of times of main scanning is M,
When <T2, the first ink ejection unit performs the last main scan on the first area, and then executes the second main scan.
The ink ejection density of the mask pattern used to eject ink in the first main scan of the ink ejection unit is 1
The ink jet recording apparatus according to claim 3, wherein the ratio is less than / M. 10. The method according to claim 10, wherein the number of times of main scanning is M,
When 1 <T2, the second region is
It is assumed that the density of the mask pattern used to discharge ink in the last main scan of the first ink discharge section before the ink discharge section starts recording is greater than 1 / M. The ink jet recording apparatus according to claim 3, wherein: 11. The method according to claim 1, wherein the number of times of main scanning is M,
When 1 <T2, the first region with respect to the second region
After the ink ejection unit performs the last main scan, the density of the mask pattern used to eject ink in the first main scan of the second ink ejection unit is 1 /
4. The ink jet recording apparatus according to claim 3, wherein the value is larger than M. 12. The printing method according to claim 8, wherein the 1 / M is set to X / M when printing is performed by multiplying the number of ejected inks per unit area by X using a mask pattern.
2. The ink jet recording apparatus according to any one of 1. 13. A mask pattern used for main scanning by the first ink ejection unit before starting recording by the second ink ejection unit on the first area is one of M main scanning operations. 9. The ink-jet apparatus according to claim 8, wherein as the number increases, the density at which the ink of the mask pattern to be used decreases. 14. A mask pattern used for main scanning by the second ink ejecting unit after recording by the first ink ejecting unit on the first area, the number of which is equal to or less than M times in the main scanning. The ink jet apparatus according to claim 9, wherein the density of ejecting the ink of the mask pattern to be used increases as the number increases. 15. A mask pattern used for main scanning by the first ink ejection unit before starting recording by the second ink ejection unit in the second area is one of M main scanning operations. 11. The ink jet apparatus according to claim 10, wherein, as the number increases, the density of ejecting the ink of the mask pattern to be used increases. 16. A mask pattern used for main scanning by the second ink ejecting unit after recording by the first ink ejecting unit on the first area is several times of M times of main scanning. 12. The ink jet apparatus according to claim 11, wherein the density of the ink of the mask pattern to be used becomes lower as the number of inks increases. 17. An ink jet recording apparatus according to claim 1, wherein the first ink ejection section and the second ink ejection section are arranged at different positions in the recording medium transport direction. 18. The printing apparatus according to claim 1, wherein the first ink ejection unit and the second ink ejection unit use different positions of the ejection unit in a recording medium conveyance direction. Ink jet recording device. 19. The ink jet recording apparatus according to claim 1, wherein the ink discharge unit includes a thermal energy generator for applying thermal energy to the ink for discharging. 20. An ink-jet apparatus which performs recording by discharging ink while performing main scanning relative to an ink discharging unit in a plurality of times on adjacent first and second areas on a recording medium. A recording method, wherein a time difference between the time when ink is ejected in a preceding main scan of the ink ejection unit and the time when ink is ejected in a subsequent main scan is T1 when recording the first area; When recording the second area, when the time difference between the time when the ink is ejected in the preceding main scan of the ink ejection unit and the time when the ink is ejected in the subsequent main scan is T2, T1 ≠ T2, The ink ejection is performed such that the ink amount per unit area ejected in the main scan preceding the first area is different from the ink amount per unit area ejected in the main scan preceding the second area. An ink jet recording method comprising: driving an output portion to discharge ink.