JP4854322B2 - Inkjet recording apparatus and recording adjustment method - Google Patents

Description

The present invention relates to an ink jet recording apparatus and a recording adjustment method.

  Generally, in an ink jet recording apparatus, a plurality of nozzles are arranged in a recording head. Further, it is known that an electrothermal conversion element, an electromechanical conversion element, or the like provided in each nozzle generates discharge energy in the nozzle to discharge ink in the nozzle to form an image on a recording medium. Yes. This ink jet recording apparatus performs recording without contact with a recording medium. Therefore, there is an advantage that noise during driving is low and color recording can be realized relatively easily with an inexpensive, small and simple configuration.

  As the configuration, a serial recording method is employed in which a recording head for ejecting ink according to the recording information to be recorded is mounted on the carriage, and recording is performed while performing reciprocating scanning in a direction crossing the feeding direction of the recording medium. The The serial recording method is generally widely used because it is inexpensive and easy to downsize.

  In recent years, in order to improve the recording speed, reciprocal recording or bidirectional recording is performed by ejecting ink from the recording head during both forward and backward scanning when the carriage is moved relative to the recording medium. A recording method called recording is also employed.

  In such an ink jet recording apparatus, it is necessary to devise a method for eliminating the deviation of the landing positions of the ink droplets in the forward path and the backward path. Therefore, it is usually used that ink droplets are ejected in an area where the recording head moves at a constant speed. That is, with respect to the timing corresponding to the ejection position in the forward path, control is performed so that the ink droplets are ejected at a timing obtained by adding a predetermined delay time to the previous timing in the backward path. Thereby, registration adjustment in reciprocal recording (hereinafter also simply referred to as “registration adjustment” or “recording alignment”) is performed (for example, see Patent Document 1).

  In addition, in an inkjet recording apparatus that uses a plurality of recording heads, such as a recording apparatus that performs full-color recording, each dot formed by ink ejected from these recording heads is controlled to have a predetermined positional relationship. . For example, it is known to perform registration adjustment so that the positional relationship formed on substantially the same location on the recording medium can be maintained (see, for example, Patent Document 2).

In a conventional example of this registration adjustment, a predetermined check pattern is recorded on a recording medium by each recording head, and the ejection timing of each recording head is adjusted based on the mutual shift between the patterns. In particular, in recent years, high-speed and high-density recording is required. As a recording head that makes this requirement possible, it has a common liquid chamber that supplies ink to a plurality of discharge ports, and the discharge ports are arranged in a staggered manner on both sides of the common liquid chamber, so that two rows of ink discharge ports Recording heads forming rows are known.
JP 2003-72056 A JP-A-10-264485 Japanese Patent Laid-Open No. 11-368345

  However, in order to handle ink that is a fluid in an ink jet recording apparatus, if the ink existing in the recording head vibrates due to the movement of the carriage on which the recording head is mounted, the meniscus formed at the nozzle ejection port also vibrates greatly due to the vibration. Resulting in. For this reason, when ink droplets are ejected with an inappropriate meniscus, the quality of the recorded image may be deteriorated. In particular, in an ink jet recording head in which a large number of ejection openings are arranged for high density recording, the amount of ink movement per unit time is large. As a result, the inertial force that tends to move forward (recording head side) of the ink when ejection is stopped is also increased. Then, a positive pressure is applied to the meniscus formed at the discharge port by this inertial force, and the meniscus may bulge outward. In this state, when a drive signal is input to the electrothermal conversion element provided corresponding to the ejection port and bubbles are generated, splash or mist ink is ejected in addition to ink droplets.

  At this time, the ink droplet is referred to as a main ink droplet, and a splash-like or mist-like ink droplet having a smaller amount than the main ink droplet is referred to as a mist. Since this mist is lighter in weight than the main ink droplet, the mist adheres to a position different from the main ink droplet on the recording medium, or the recording device is subjected to an airflow generated by continuous ink droplet ejection from the recording head. Or float inside. As described above, there is a problem in that the quality of the recorded image is deteriorated or the inside of the ink jet recording apparatus is soiled by discharging mist other than the main ink droplets.

  Further, when the inside of the ink jet recording apparatus is soiled, there is a possibility that the recording medium to be recorded next is soiled or an error occurs in the carriage scanning control.

  FIG. 1 is a waveform diagram showing a pressure oscillation waveform in an ink flow path with respect to an ejection pulse when an ink ejection operation is performed by a recording head.

  2A, 2B, and 2C show recording heads in the A section (before discharge start), B section (during discharge operation), and C section (just after discharge stop) in FIG. It is an expanded sectional view which shows the mode of the meniscus formed in this discharge outlet.

  As shown in FIG. 1, when the amplitude “a” of the pressure vibration in the ink flow path after stopping the discharge is large and the pressure in the flow path is positive, this vibration causes the vibration of the meniscus at the next ink discharge. Will be disturbed. Specifically, in period A in FIG. 1, a stable meniscus M in a state of being slightly recessed inward from the opening of the ink discharge port 5 is formed as shown in FIG. In this state, when the ejection operation (pulse driving for the electrothermal conversion element 2) is started as in the period B in FIG. 1, good ink droplets 50 are formed as shown in FIG. When the period C immediately after the ejection is stopped, the pressure in the ink flow path 10 becomes a large positive pressure due to the inertia of the ink flowing toward the ejection port 5.

  Therefore, as shown in FIG. 2C, a meniscus M that is raised outward from the opening of the ink discharge port 5 may be formed, or ink may drip from the ink discharge port 5. When the next ink ejection operation is performed in the state shown in FIG. 2C, minute ink droplets are ejected, which may cause splash and ink mist.

  In a serial scanning type inkjet recording apparatus using a recording head having a common liquid chamber for supplying ink to a plurality of ejection openings and forming two rows of ink ejection openings on both sides of the common liquid chamber, the recording head reciprocates. Therefore, a fluid force is generated by the inertial force in the ink in the common liquid chamber. In this case, since the ink flow force is generated rearward in the scanning direction of the recording head, negative pressure is applied to the meniscus in the ejection port array located on the front end side in the scanning direction of the common liquid chamber. Therefore, vibration during ink ejection is suppressed, so that a good ink ejection state can be obtained.

  However, in the ejection port array located on the rear end side in the scanning direction of the common liquid chamber, positive pressure is applied to the meniscus by the ink flow force, so that ink vibration is emphasized. Accordingly, since the vibration during ink ejection is emphasized, the ink ejection state is deteriorated. Even if the configuration in which the flow resistance of the ink is adjusted by changing the shape of the common liquid chamber or the diameter of the filter provided in the common liquid chamber is employed, the recording head having two rows of ejection orifices may There is a high possibility that mist is generated due to the positive pressure increased by the flow force. Therefore, in an inkjet recording apparatus using a recording head in which two ejection port arrays are formed, there is a possibility that problems such as a decrease in the quality of recorded images and contamination inside the inkjet recording apparatus may occur.

  In addition, in an ink jet recording apparatus that performs bidirectional recording in which ink is ejected during both forward scanning and backward scanning of the recording head, splash and mist adhere to the recorded image (pattern) when performing registration adjustment. To do. In addition, since the adhesion direction in the forward scan of the mist is different from the adhesion direction in the backward scan, the accuracy of the reciprocal registration adjustment is deteriorated, and the quality of the resulting recorded image is remarkably deteriorated. was there.

  Furthermore, in an ink jet recording apparatus using a plurality of recording heads, the degree of occurrence of splash and mist generated from each ejection port varies, so that registration adjustment for maintaining the mutual positional relationship between the heads is performed with high accuracy. There was a problem that I could not.

Accordingly, the present invention has been made to solve the above-described problems, and can sufficiently suppress the occurrence of splash and mist accompanying the scanning of the recording head and stably obtain a high-quality image. An object is to provide an ink jet recording apparatus and a recording adjustment method.

  In order to achieve the above object, an embodiment of the present invention comprises the following arrangement.

That is, according to one aspect of the present invention, there is provided a first ejection port array in which a plurality of ejection ports that communicate with a common liquid chamber for supplying ink and that eject ink are arranged on one side of the common liquid chamber; A second discharge port formed by arranging a plurality of discharge ports that communicate with the common liquid chamber along the first discharge port row on the opposite side of the first discharge port row with the common liquid chamber interposed therebetween. Ink jet recording for recording an image on a recording medium by ejecting ink while a recording head having a row is scanned in a forward direction and a backward direction that intersect the direction in which the ejection ports in the first ejection port array are arranged A device,
Ink is ejected using the ejection ports belonging to the first ejection port array while scanning in either the forward direction or the backward direction, and the ejection ports belonging to the second ejection port array are used. In order to obtain the first shift amount between the recording position by the ejection port belonging to the first ejection port array and the recording position by the ejection port belonging to the second ejection port array by ejecting ink. First control means for recording the first pattern on the recording medium;
While performing scanning in the forward direction, ink is ejected using only the ejection ports belonging to the first ejection port array located on the leading side in the forward direction, and while scanning in the backward direction is performed. By ejecting ink using only the ejection ports belonging to the second ejection port array located on the head side in the return path direction, the ejection ports belonging to the first ejection port array in the scanning in the forward direction A second pattern for recording on the recording medium a second pattern for acquiring a second shift amount between the recording position by the recording head and the recording position by the ejection ports belonging to the second ejection port array in the backward scanning. Control means,
The first ejection port array and the second ejection port at the time of scanning in the same scanning direction based on the first shift amount acquired using the first pattern recorded on the recording medium The first ejection timing adjustment value for correcting the recording position along the scanning direction by the ejection ports belonging to the column is obtained, and obtained using the second pattern recorded on the recording medium. Based on the second shift amount , a first position for correcting the recording position along the scanning direction by the first ejection port array and the ejection ports belonging to the second ejection port array at the time of scanning in different scanning directions. 2 discharge timing adjustment values are obtained, and the first discharge timing adjustment value obtained by using the first discharge timing adjustment value and the second discharge timing adjustment value is used for the first discharge port array. Outward way by the outlet And having the timing of the discharge in the scan of the adjustment means for adjusting the timing of the discharge in the backward direction of the scan.

  According to the present invention, only the ejection port array on the head side in the scanning direction of the recording head is driven, and only the ejection port having a stable meniscus is used. Therefore, it is possible to perform highly accurate registration adjustment and image formation with suppressed generation of splash and mist.

  Hereinafter, preferred embodiments of the present invention will be described.

  FIG. 3 is a partially cutaway perspective view for explaining a schematic configuration of the ink jet recording apparatus according to the present embodiment. Note that the ink jet recording apparatus according to the present embodiment employs a serial scanning method in which the recording head is reciprocated in the main scanning direction.

  In FIG. 3, reference numeral 100 denotes a carriage on which recording heads 110Y, M, C, and BK (see FIG. 4) for ejecting ink are detachably mounted. The carriage 100 is supported by a guide shaft 102 extending along the main scanning direction (X direction). The carriage 100 is moved along the forward scanning direction X1 and the backward scanning direction X2 along the guide shaft 102 by the endless belt 104 driven in the forward direction or the reverse direction according to the rotation of the motor 103. The endless belt 104 is stretched between the pulleys 105 and 106, and the rotation of the motor 103 is transmitted to the endless belt 104 via the pulley 105.

  The carriage 100 is mounted with a plurality of recording heads 110Y, 110M, BK, and BK that eject different types of ink, and a plurality of ink tanks that supply ink to each recording head. In this embodiment, four recording heads 110Y, M, C, and BK corresponding to yellow, magenta, cyan, and black inks are mounted. Further, a tank 101Y for supplying yellow ink, a tank 101M for supplying magenta ink, a tank 101C for supplying cyan ink, and a tank 101BK for supplying black ink are mounted on the carriage 100 so as to be detachable.

  In the inkjet recording apparatus 200 having the above-described configuration, the recording paper P as a recording medium is intermittently conveyed in the sub-scanning direction (arrow Y direction) that intersects the main scanning direction (arrow X direction) substantially at right angles. In this intermittent conveyance operation, a pair of rollers 107 and 108 positioned upstream in the sub-scanning direction with respect to the recording head and a pair of conveyance rollers 109A and 109B positioned downstream are sandwiching the recording paper P, respectively. However, it is performed by rotating intermittently.

  Since the two pairs of transport rollers rotate so as to apply a constant tension to the recording paper P, the recording paper P sandwiched between the two pairs of transport rollers is held in a plane at a position facing each recording head 110. The The rotational force of each roller pair is applied by a drive motor in the drive unit 111. The ink jet recording apparatus 200 is provided with a home position for waiting the recording head 110 outside a recording area where an image can be formed on a recording medium by reciprocating scanning of the carriage 100. At this home position, there is a cap member 112 that caps the ejection port surface on which the ejection port of each recording head 110 is formed, and a wiping member (not shown) that wipes off dust and ink adhering to the ejection port surface of the recording head 110. Is provided.

  Further, the cap member 112 is a recovery means that forcibly sucks ink from the discharge port on the discharge port surface by generating a negative pressure in the cap member 112 in a state where the cap member 112 and the discharge port surface are in contact with each other. (Not shown) is provided. An operation of discharging the thickened ink in the recording head by sucking ink from the ejection port by the recovery means is referred to as a suction recovery operation. By performing this recovery operation, the ejection state of the ink droplets ejected from the recording head 110 can be kept good, and clogging in the ejection ports can be reduced. In addition to the suction recovery operation, the recovery operation includes a preliminary discharge operation for discharging ink droplets from the respective discharge ports of the recording head 110 into the cap member 112, and a wiping member for removing dust and ink adhering to the discharge port surface. There is a wiping operation to wipe off.

  This recovery operation is performed at a predetermined timing such as when the ink jet recording apparatus is turned on, at the start of recording, during recording, after the end of recording, or at a predetermined interval (time interval or total number of ejections). Therefore, when the recovery operation is performed, the carriage 100 moves to the home position. If a recovery mechanism is provided on the opposite side of the home position across the recording area to maintain a good discharge state of the recording head 110, not only the home position but also other different recording area end portions. The recovery operation is also performed at the position where the recovery mechanism is provided.

  Here, based on FIG. 4 and FIG. 5, a specific configuration example of the recording head 110 in the present embodiment will be described. 4 is a partial plan view showing the structure of the recording head 110, and FIG. 5 is a cross-sectional view taken along the line VV of FIG. The recording head 110 used in this embodiment is mounted on the carriage 100 of the ink jet recording apparatus 200, and the arrow X1 side in FIG. 5 is the forward scanning side of the recording head, and the arrow X2 side is the backward scanning side of the recording head. It is said.

  4 and 5, reference numeral 1 denotes a substrate. An insulating layer 1a is formed on the substrate 1, and ink supplied from an ink tank is supplied to the central portion of the substrate 1 and the insulating layer 1a. A supply port 11 is formed. Reference numeral 4 denotes an orifice plate formed on the substrate 1, and a common liquid chamber 10 communicating with the ink supply port 11 is formed between the orifice plate 4 and the substrate 1 as shown in FIG. . As shown in the plan view of FIG. 4, the supply liquid chamber 10 extends to the left and right sides (the forward scanning direction X1 and the backward scanning direction X2) of the ink supply port 11, and the flow path is closed at both ends. It has become. A plurality of partition walls 9 are formed at regular intervals in the left and right side portions of the common liquid chamber 10 in the longitudinal direction of the substrate (the conveyance direction (Y direction) of the recording paper P). Thus, a plurality of ink supply portions 10a are formed.

  Reference numeral 5 denotes an ink discharge port formed in the orifice plate 4 in each ink supply unit 10 a of the common liquid chamber 10. The ink discharge ports 5 are located near the left end and the right end of each ink supply unit 10a (near the front end in the forward scanning direction and near the front end in the backward scanning direction). Reference numeral 2 denotes an electrothermal conversion element (hereinafter also referred to as “heater”) as an ejection energy generating element formed on the substrate 1, and the head driver 307 (FIG. 6) is connected through a conduction portion not shown. Is electrically connected). The electrothermal conversion element 2 is disposed at a position facing the discharge port 5, and a protective film or the like is formed on the surface of the electrothermal conversion element 2.

  In this embodiment, the ink supply port 11 of the substrate 1 made of silicon is formed by anisotropic etching. The ink supplied from the ink tank 101 is supplied from the common liquid chamber 10 to the respective ink supply units 10a arranged on the left and right sides thereof. Film boiling occurs due to the thermal energy of the heater 2 in the ink supplied to each ink supply unit 10a, and the ink is ejected as ink droplets from the ink ejection port 5 by the pressure of bubbles generated at that time.

  As shown in FIG. 4, the ejection ports 5 are arranged in a zigzag pattern to form two ink ejection port arrays 51 and 52. Each of the ejection port arrays 51 and 52 includes 640 ejection ports 5 arranged in a predetermined direction (“predetermined direction” means a direction intersecting the scanning direction) at a pitch of 600 dpi. However, in the two discharge port arrays 51 and 52, the positions of the discharge ports 5 are shifted from each other by a half pitch. Therefore, each recording head 110 can substantially achieve the same recording density as that in which the ejection ports 5 are arranged in a vertical row at a pitch of 1200 dpi.

  Further, a heater 2 is disposed almost directly below each discharge port 5. The constituent members of the common liquid chamber 10 such as the partition walls 9 are formed by a known manufacturing method such as an exposure technique or etching. For example, the discharge port 5 is formed by a cylindrical through hole having a diameter of 20 μm, and the size of the heater 2 is 24 μm × 24 μm. The height H of the common liquid chamber 10 formed between the substrate 1 and the orifice plate 4 is 15 μm, and the thickness W of the orifice plate 4 is 10.5 μm. The distance L between the substrate 1 and the outer surface of the orifice plate 4 is 25.5 μm.

  Next, a schematic configuration of the control system 201 in the inkjet recording apparatus 200 in the present embodiment will be described based on FIG.

  The ink jet recording apparatus 200 receives recording information of an image to be recorded from a host computer 300 or the like connected to the outside. The inkjet recording apparatus 200 temporarily stores recording information received via the input / output interface 301 in a memory (also referred to as a reception buffer) provided in the inkjet recording apparatus 200. A part of the RAM 304 may be used for the reception buffer. The CPU 302 that controls the operation of the inkjet recording apparatus 200 converts the recording information temporarily stored in the reception buffer into data that can be processed in the inkjet recording apparatus 200 and stores it in the RAM 304. Further, the CPU 302 controls the motor driver 305 and the head driver 307 according to the data stored in the RAM 304 based on the control program stored in the ROM 303. The CPU 302 drives a driving motor 306 such as a head movement motor (carriage motor) or a conveyance motor via the motor driver 305, and discharges ink from the recording head via the head driver 307.

  Data stored in the RAM 304 (also referred to as a recording buffer) includes recording data converted into binarized data (recording data) indicating whether or not ink dots are to be formed on the recording paper P. Further, in order to land the ink ejected from the recording head at an appropriate position on the recording paper P, it is used for driving a transport motor that is a driving source of the recording paper P transport operation, a carriage motor that moves the recording head 110, and the like. A motor drive signal for driving the motor 306 is included. This motor drive signal is input to the motor driver 305 to synchronize the movement of the carriage 100 in the main scanning direction and the conveyance of the recording paper P. In addition, print data and print head drive data output from the CPU 302 are input to the head driver 307 that drives the heater 2 provided in each nozzle of the print head 110, and the heater 2 corresponds to both data. To discharge ink.

<Embodiment 1>
Next, reciprocal registration adjustment control in the first embodiment of the present invention will be described. Note that the ink jet recording apparatus according to the present embodiment includes four recording heads including the recording heads 110Y, 110M, 110C, and 110BK. However, since the operation principle is basically the same, recording is performed here. The case of the head 110BK will be described.

  First, as shown in FIG. 7, the first check pattern is recorded by one recording scan, and is ejected from the first ejection port array 51 and the second ejection port array 52 of the recording head 110BK. The registration adjustment between the ejection openings is performed so that the recording position with the ink droplet is matched. This pattern is recorded in a substantially central portion with respect to the main scanning direction on the recording paper P. That is, first, after the recording paper P is fed and conveyed, the first and second discharges are performed while the carriage 100 is scanned once in a substantially central portion (a range where the first check pattern can be recorded) on the recording paper P. Ink is discharged from the plurality of outlets of the outlet rows 51 and 52 at a predetermined timing.

  At this time, the ink droplets ejected from the ejection ports of the first ejection port array 51 are ejected at predetermined equal time intervals, whereby the first composed of a plurality of patterns as indicated by black dots in FIG. The check pattern is formed. On the other hand, the ink droplets ejected from the ejection ports of the second ejection port array 52 are ejected at the timing of each of the plurality of patterns forming the second pattern, as shown by white dots in FIG. A first check pattern composed of a plurality of patterns is formed. The pattern at the center of the plurality of patterns arranged in the main scanning direction has a recording position of a pattern formed by ink droplets ejected from the respective ejection ports of the first ejection port array 51 and the second ejection port array 52. Ink droplets are ejected from the second ejection port at a timing that coincides.

  The timing at which the recording positions (also referred to as landing positions) coincide is the timing at which the recording positions set in the recording apparatus at the time when the first check pattern is recorded coincide with each other. It is also referred to as “0” position timing. When there is no error in the mechanism of the recording apparatus, the first check pattern recorded at the timing of the “0” position is represented by the line formed by the first ejection port array 51 and the second ejection port array 52. The formed line overlaps. The two patterns on the left side of FIG. 7 are check patterns recorded at the timings of “−2” and “−1” positions, respectively. At this time, the timing at which the landing position of the ink droplet ejected from the second ejection port array 52 is shifted by 2 or 1 dot in the right direction with respect to the landing position of the ink droplet ejected from the first ejection port array 51. Thus, ink droplets are ejected from the ejection ports of the second ejection port array 52. Similarly, the two patterns on the right side of FIG. 7 are check patterns recorded at timings of “+1” and “+2” positions, respectively, and the ink droplets ejected from the second ejection port array 52 are the first ejection port array. The ink droplets ejected from 51 are shifted by one or two dots in the left direction.

  The one dot corresponds to an interval of about 21 μm in the case of 1200 dpi. Further, if it is known whether the recording position of the first check pattern is correct, even if ink droplets are ejected from all of the first and second ejection port arrays 51 and 52, the first and second ejection port arrays The pattern may be formed using only a predetermined discharge port among the 51 and 52 discharge ports.

  In the example shown in FIG. 7, it can be observed that the first ejection port array 51 and the second ejection port array 52 overlap at the timing of the position “0”. Therefore, the timing of this position is input through an operation key provided in the host computer 300, for example, and set as a registration value between discharge ports.

  Next, as the second check pattern, a pattern similar to the first check pattern is recorded by two recording scans (reciprocal printing). At this time, control is performed so that only the first ejection port array 51 is ejected in the forward scan printing, and only the second ejection port array 52 is ejected in the backward scanning printing. Specifically, recording data for ejecting ink droplets is generated by performing ejection control of the ejection port arrays 51 and 52 in each recording scan by thinning out recording data using a mask pattern.

  The mask patterns 8A and 8B in FIG. 8A and FIG. 8B are two types of thinning mask patterns complementary to each other stored in the RAM 304. Each of these thinning patterns has a recording density of 1200 dpi, and is a mask pattern corresponding to a recording area of 655360 pixels in total of 1280 pixels in the raster arrangement direction (Y direction) and 512 pixels in the column arrangement direction (X direction). ing. Among these, the thinning pattern 8A (FIG. 8A) is a striped pattern in which recording pixels are arranged every other raster, and the thinning pattern 8B (FIG. 8B) is the thinning pattern. It is a pattern having a reverse stripe shape complementary to the pattern 8A. Accordingly, in both the thinning pattern 8A and the thinning pattern 8B, the ratio of the recording allowable pixel to the total pixels in the recording area (the total of the recording allowable pixel and the non-recording allowable pixel) is 50%.

  In recording the second check pattern, first, only the portion where the print permitting pixels of the check pattern and the thinning pattern 8A in FIG. Then, in the backward scan that is the second recording scan after that, only the portion where the respective print permitting pixels of the check pattern and the thinning pattern 8B overlap is set as the print permitting pixel. That is, only the first discharge port array 51 is permitted to print in the forward scan, and only the second discharge port array 52 is controlled to permit recording in the backward scan. The second check pattern may be recorded by ejecting ink droplets from the first ejection port array 51 in the backward scanning and ejecting ink droplets from the second ejection port array 52 in the forward scanning.

  As a result of recording the second check pattern, for example, in the example shown in FIG. 10 (FIG. 7), the ejection positions of the forward scanning recording and the backward scanning recording match at the timing of the position “0”. Is set as a new reciprocal recording timing setting value.

  The reciprocating recording timing setting value by the second check pattern obtained by the above control is the timing setting value for the first ejection port array 51 for the forward scanning and the second ejection port array 52 for the backward scanning. However, in general, in order to perform registration adjustment to match the recording position in the reciprocating recording scan, the timing setting in the reciprocating scan is performed so that the recording position when the reciprocating recording is performed using the ejection ports of the first ejection port array 51 is matched. A value is required. Usually, since the mutual positional relationship between the first ejection port array 51 and the second ejection port array 52 is determined by the assembly configuration of the recording head 110, it is not easily affected by disturbance, and its timing setting value is incorrect. Hateful. On the other hand, the timing setting values in forward scanning and backward scanning recording tend to fluctuate due to variations in mechanism, durability, environmental changes, etc., and high-precision registration adjustment is required.

  Therefore, in this embodiment, the reciprocal registration adjustment is performed using the reciprocal recording timing setting value derived from the second check pattern and the inter-ejection registration value derived from the first check pattern. Specifically, the reciprocating recording timing setting value derived from the second check pattern recorded by two recording scans and the inter-ejection timing setting value derived from the first check pattern recorded by one recording scanning are added. To do. Then, the timing setting values of the forward scanning recording by the first ejection port array 51 and the backward scanning recording by the first ejection port array 51 are calculated, and the reciprocal registration adjustment is performed.

  Note that the check pattern recording thinning control and timing data setting based on the check pattern described above can be executed by a control program recorded in a memory such as the CPU 302, the RAM 304, and the ROM 303 in FIG.

  FIG. 9 is a flowchart showing a processing procedure relating to the recording of the first check pattern and the second check pattern described above. This processing is started when the recording paper P is set at the paper feeding position and a predetermined check pattern recording instruction is input. First, in step S1001, an ejection port array registration adjustment pattern (first check pattern), which is a check pattern, is recorded in a substantially central portion of the recording paper P.

  Here, the user observes the check pattern on the recording paper P as described above, and inputs the timing setting value between the ejection port arrays (registration setting value between ejection ports). In step S1002, this setting is performed. Wait for value input. When there is this set value input, in step S1003, the ejection port row registration adjustment value P1 is stored in the RAM 304 based on the input. The stored parameter P1 is used for timing setting in each recording scan using the two ejection port arrays of the recording head 110BK, including the recording in step S1004 described below.

  When the input of the parameter P1 is completed, in step S1004, the thinning pattern 8A and the thinning pattern 8B stored in the ROM 303 are read, and a reciprocating registration adjustment pattern (second check pattern) is recorded based on the check pattern.

  In the next step S1005, as in step S1002, the user waits for the input of the reciprocal recording timing setting value. If this input is received, a reciprocal registration set value P2 is calculated based on the value and the ejection port array registration adjustment value P1 recorded in the RAM 304 in step S1006, and the calculated value is stored in the RAM 304. . This value is used for setting the timing in bidirectional recording.

  FIG. 10 is an example of a reciprocal registration adjustment pattern recording result applied to this embodiment, and FIG. 11 is an example of a reciprocal registration adjustment pattern recording result when the present invention is not applied. In FIG. 10, reference numeral 901 denotes an ejection recording pixel by forward scanning, and reference numeral 902 denotes an ejection recording pixel by backward scanning. In FIG. 10, only the first ejection port array 51 is used for forward scanning, and the second ejection port is used for backward scanning. Only the column 52 is discharged. By carrying out the present invention, when recording a pattern for reciprocal registration adjustment, only a stable meniscus discharge port can be used, and the occurrence of splash and mist is suppressed. As a result, satellites hardly appear in FIG. 10, and it is easy to select “0” as the timing selection in the user's observation.

  On the other hand, in FIG. 11, printing is performed from all the ejection port arrays 51 and 52 without distinction between forward scanning and backward scanning. For this reason, satellites frequently appear in the discharge from the discharge port row where the meniscus is not stable (the second discharge port row 52 in the forward scan and the first discharge port row 51 in the backward scan). Furthermore, “+1” may be selected in the timing selection in the user's observation depending on the relationship between the dots of the main ink droplets. In this case, since the relationship between the main ink droplets is slightly deviated, the accuracy of registration adjustment is lowered, and the problem of deteriorating the resolution of the recorded image is likely to occur.

  In the timing selection in FIG. 10, when “0” is selected, the landing positions of the main ink droplets are the most coincident, and the registration adjustment is performed in such a state, whereby the recorded image is displayed. Therefore, it is possible to perform high-quality recording. As described above, when reciprocal registration adjustment is performed by a series of processes, since only the ejection port array positioned at the head side is ejected in each recording scan, only the stable meniscus ejection port is used. Can be used. Accordingly, it is possible to record a high quality check pattern while suppressing the occurrence of splash and mist. Therefore, setting values can be easily selected by user observation, which not only improves the accuracy of registration itself, but also has the advantage that high image quality can be achieved in an actual recorded image.

  In the present embodiment, the timing selection between the first ejection port array 51 and the second ejection port array 52 is a method based on user observation. However, the timing is automatically determined by reading a recorded image using an optical sensor or the like. The configuration may be such that selection is performed. That is, the effect is not limited by the timing selection method as long as it uses the leading ejection port array in the scanning direction.

  In addition, a check pattern similar to the pattern for adjusting ejection port array registration is used to select the timing of reciprocal recording, and control is performed so that only the head ejection port array in the scanning direction is ejected by thinning the pattern with the thinning pattern. It was set as the structure to do. However, another check pattern may be used in each timing selection, and the check pattern itself may be configured to discharge only the leading discharge port array in the scanning direction. In other words, the effect is not limited by the control method as long as the head side ejection port array in the scanning direction is used.

<Embodiment 2>
Next, a second embodiment of the present invention will be described. In this second embodiment as well, the recording apparatus does not perform reciprocal registration adjustment, but performs registration adjustment between a plurality of recording heads, as in the first embodiment. And it has the structure shown in FIGS.

  FIG. 12 is a check pattern for adjusting the registration between print heads used in the present embodiment. In this embodiment, since recording is performed with four colors of BK, C, M, and Y, the pattern can be adjusted for registration between the four recording heads. This pattern is recorded in a substantially central portion with respect to the main scanning direction on the recording paper P. That is, while scanning the carriage 100 once, ink is ejected from the first ejection port array of the recording head 110Bk at predetermined equal time intervals, and ink is ejected from the first ejection port array of the recording head 110C at a predetermined timing. . At this time, the recording head 110 </ b> C forms each pattern at the timings “−2” to “+2” as described in the first embodiment.

  Next, after the recording paper P is conveyed by the driving motor in the driving unit 111, the check pattern formed by the recording head 110Bk and the recording head 110M and the check pattern formed by the recording head 110Bk and the recording head 110Y are similarly recorded. To do. That is, “-2”, “−1”, and “+1” are timings that are overlapped with the landing positions of the ink droplets ejected from the recording head 110BK and positions that are shifted to the left and right by 2 dots and 1 dot, respectively. , Discharge is performed from the first discharge port at one timing of “+2”.

  As a result of recording the check pattern by the plurality of recording heads, for example, in the example shown in FIG. 13, the ejection positions of the recording head 110BK and the other recording heads 110 (C, M, Y) overlap at the timing of the position “0”. Therefore, the timing corresponding to this position is set as a new timing.

  FIG. 13 is a flowchart showing a processing procedure for inter-head registration adjustment using the check pattern described above. When the recording paper P is set at the paper feeding position and a predetermined check pattern recording instruction is input, this processing is started. In step S1401, an inter-recording head registration adjustment pattern, which is a check pattern, is displayed at a substantially central portion of the recording paper P. Record.

  Here, the user observes the check pattern on the recording paper P as described above and inputs the timing setting value between the recording heads. In step S2402, the setting value between the recording head 110BK and the recording head 110C is input. Wait for input. If there is this setting value input, the setting value input between the recording head 110BK and the recording head 110M is similarly waited in step S1403, and further the setting value input between the recording head 110BK and the recording head 110Y is waited in step S1404. . When the input of these set values is completed, the print head registration adjustment value is stored in the RAM 304 based on the setting (step S1405). The stored parameters are used for timing setting between the recording heads.

  FIG. 14 is a diagram showing an example of the pattern recording result for registration adjustment between recording heads when the present invention is not applied. In the figure, reference numeral 903 denotes an ejection recording pixel by the recording head 110BK, 904 denotes a recording head 110C, 905 denotes a recording head 110M, and 906 denotes an ejection recording pixel by the recording head 110Y. According to the embodiment of the present invention, only the first discharge port having a stable meniscus can be used when recording the registration adjustment pattern between the recording heads. In order to suppress the occurrence of splash and mist, FIG. There is almost no satellite appearance. Therefore, when timing is selected in the user's observation, “0” with the best recording position is easily selected.

  On the other hand, in FIG. 14, since recording is performed without distinction between the ejection port arrays, satellites frequently appear in ejection from the ejection port array where the meniscus is not stable (second ejection port array in forward scanning). Therefore, the pattern formed by the main ink droplets and the mist may select “+1” instead of “0” when selecting timing in the user's observation. If “+1” is selected by mistake, the relationship between the main ink droplets is slightly deviated, resulting in a problem that the accuracy of registration adjustment is reduced and the image quality of the recorded image is deteriorated. End up. When “0” is selected in the timing selection in FIG. 13, registration adjustment is performed in a state in which the relationship between the main ink droplets most closely matches, so that the image quality of the recorded image is good and high-quality recording is performed. Can be done.

  As described above, when the registration adjustment between the print heads is performed by a series of processes, control is performed so that only the first discharge port array positioned on the head side is discharged in the forward scan of the unidirectional printing. As a result, only a stable meniscus discharge port can be used, and a high-quality check pattern can be recorded while suppressing the occurrence of splash and mist. Therefore, setting values can be easily selected by observation by the user, and there is an advantage that not only the accuracy of the registration itself is improved but also high image quality can be achieved in an actual recorded image. In this embodiment, the check pattern recording control is performed by the forward scanning recording in the unidirectional recording. However, the effect is not limited by the scanning direction. Even in the backward scanning recording, the check pattern recording control is performed. It is sufficient to control so that only the ejection port array to be driven is driven.

  Further, in the present embodiment, the timing is set between a plurality of recording heads by adjusting the registration between the BK recording head and the other color recording heads. However, the configuration may be such that registration adjustment is performed between the C recording head and the other recording heads, and the selected recording head is not limited.

  The object of the present invention can also be achieved by supplying a system or apparatus with a storage medium storing software program codes for realizing the functions of the above-described embodiments. That is, it goes without saying that this can also be achieved by the computer (or CPU or MPU) of the system or apparatus reading and executing the program code stored in the storage medium. 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.

  As a storage medium for supplying the program code, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile semiconductor memory card, ROM, or the like can be used. . Further, the functions of the above-described embodiments may be realized by executing the program code read by the computer.

  However, when the OS (operating system) operating on the computer performs part or all of the actual processing based on the instruction of the program code, and the functions of the above-described embodiments are realized by the processing. Needless to say, is also included.

  Furthermore, the program code read from the storage medium may be written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer. After that, based on the instruction of the program code, the CPU of the function expansion board or function expansion unit performs part or all of the actual processing, and the processing of the above-described embodiment is realized by the processing. Needless to say.

FIG. 6 is a waveform diagram illustrating a pressure oscillation waveform in an ink flow path with respect to an ejection pulse when an ink ejection operation is performed with a recording head. FIG. 2 is an enlarged cross-sectional view of a nozzle showing a state of a meniscus in an A section (before discharge start), a B section (during discharge operation), and a C section (immediately after discharge stop) in FIG. 1. 1 is a partially cutaway perspective view for explaining a schematic configuration of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 3 is an enlarged plan view schematically showing a partial configuration of a recording head in an embodiment of the present invention. It is the VV sectional view taken on the line of FIG. 1 is a block diagram illustrating a schematic configuration of a control system of an ink jet recording apparatus according to an embodiment of the present invention. It is a schematic diagram which shows the 1st check pattern used for the 1st Embodiment of this invention. It is a schematic diagram which shows the thinning pattern used for the 1st Embodiment of this invention, (A) is a schematic diagram which shows the thinning pattern 1, and (B) is a thinning pattern 2 in the figure. It is a flowchart explaining the reciprocating recording registration adjustment process performed in the 1st Embodiment of this invention. It is an example figure which shows the 2nd check pattern printing result to which the 1st Embodiment of this invention is applied. It is an example figure which shows the 2nd check pattern printing result when not applying the 1st Embodiment of this invention. It is a schematic diagram which shows the check pattern used for the 2nd Embodiment of this invention. 10 is a flowchart for describing an inter-head registration adjustment process executed in the second embodiment of the present invention. It is an example figure which shows the check pattern printing result when not applying the 2nd Embodiment of this invention.

Claims (6)

A first ejection port array in which a plurality of ejection ports that communicate with a common liquid chamber for supplying ink and that eject ink are arranged on one side of the common liquid chamber; A recording head comprising: a second discharge port array formed by arranging a plurality of the discharge ports communicating with the common liquid chamber along the first discharge port array on the opposite side to the one discharge port array; An inkjet recording apparatus that records an image on a recording medium by ejecting ink while scanning in a forward direction and a backward direction that intersect the direction in which the ejection ports in the first ejection port array are arranged,
Ink is ejected using the ejection ports belonging to the first ejection port array while scanning in either the forward direction or the backward direction, and the ejection ports belonging to the second ejection port array are used. In order to obtain the first shift amount between the recording position by the ejection port belonging to the first ejection port array and the recording position by the ejection port belonging to the second ejection port array by ejecting ink. First control means for recording the first pattern on the recording medium;
While performing scanning in the forward direction, ink is ejected using only the ejection ports belonging to the first ejection port array located on the leading side in the forward direction, and while scanning in the backward direction is performed. By ejecting ink using only the ejection ports belonging to the second ejection port array located on the head side in the return path direction, the ejection ports belonging to the first ejection port array in the scanning in the forward direction A second pattern for recording on the recording medium a second pattern for acquiring a second shift amount between the recording position by the recording head and the recording position by the ejection ports belonging to the second ejection port array in the backward scanning. Control means,
The first ejection port array and the second ejection port at the time of scanning in the same scanning direction based on the first shift amount acquired using the first pattern recorded on the recording medium The first ejection timing adjustment value for correcting the recording position along the scanning direction by the ejection ports belonging to the column is obtained, and obtained using the second pattern recorded on the recording medium. Based on the second shift amount , a first position for correcting the recording position along the scanning direction by the first ejection port array and the ejection ports belonging to the second ejection port array at the time of scanning in different scanning directions. 2 discharge timing adjustment values are obtained, and the first discharge timing adjustment value obtained by using the first discharge timing adjustment value and the second discharge timing adjustment value is used for the first discharge port array. Outward way by the outlet An ink jet recording apparatus characterized by comprising an adjusting means for adjusting the timing of the discharge in the backward direction of the scan with the timing of the discharge in the scan. A first ejection port array in which a plurality of ejection ports that communicate with a common liquid chamber for supplying ink and that eject ink are arranged on one side of the common liquid chamber; and the first liquid ejection chamber sandwiching the common liquid chamber A discharge means including a second discharge port array formed by arranging a plurality of the discharge ports communicating with the common liquid chamber along the first discharge port array on the opposite side to the first discharge port array; A plurality of recording heads provided as a first ejection unit corresponding to one color ink and a plurality of second ejection units corresponding to a second color ink different from the first color; An inkjet recording apparatus that records an image on a recording medium by ejecting ink while scanning in the forward direction and the backward direction intersecting with the direction in which the ejection ports are arranged in the ejection port array,
While performing scanning in the forward direction, only the discharge ports belonging to the first discharge port array located on the leading side in the forward direction of each of the first discharge unit and the second discharge unit are used. By ejecting ink, the recording position by the ejection ports belonging to the first ejection port array of the first ejection means in the forward scan and the first ejection port of the second ejection means Control means for recording on the recording medium a pattern for obtaining a deviation amount A from the recording position by the ejection port belonging to the row;
The first ejection unit and the second ejection unit at the time of scanning in the forward direction based on the deviation amount A acquired using the pattern recorded on the recording medium. An ejection timing adjustment value for correcting the recording position along the scanning direction of the recording head by each ejection port belonging to the ejection port array is acquired, and a plurality of ejection units from the plurality of ejection units are acquired by the acquired ejection timing adjustment value . An ink jet recording apparatus comprising: adjusting means for adjusting ink ejection timing. The control means includes
Only the discharge ports belonging to the second discharge port row located on the leading side in the return path direction of each of the first discharge unit and the second discharge unit are used while scanning in the return path direction. By performing ink ejection, the recording position by the ejection ports belonging to the first ejection port array in the backward scanning and the recording position by the ejection ports belonging to the second ejection port array in the backward scanning. And a control for recording on the recording medium a pattern for acquiring a deviation amount B from
The adjusting means includes
The first ejection unit and the second ejection unit at the time of scanning in the backward direction based on the deviation amount B acquired using the pattern recorded on the recording medium. An ejection timing adjustment value for correcting the recording position along the scanning direction of the recording head by each ejection port belonging to the ejection port array is acquired, and a plurality of ejection units from the plurality of ejection units are acquired by the acquired ejection timing adjustment value . The ink jet recording apparatus according to claim 2, wherein the ink ejection timing is adjusted. The inkjet recording apparatus according to claim 2, wherein the first color ink is a black ink, and the second color ink is a color ink. A first ejection port array in which a plurality of ejection ports that communicate with a common liquid chamber for supplying ink and that eject ink are arranged on one side of the common liquid chamber; and the first liquid ejection chamber sandwiching the common liquid chamber A recording head comprising: a second discharge port array formed by arranging a plurality of the discharge ports communicating with the common liquid chamber along the first discharge port array on the opposite side to the one discharge port array; A recording adjustment method in an ink jet recording apparatus for recording an image on a recording medium by discharging ink while scanning in a forward direction and a backward direction intersecting with a direction in which the discharge ports in the first discharge port array are arranged,
Ink is ejected using the ejection ports belonging to the first ejection port array while scanning in either the forward direction or the backward direction, and the ejection ports belonging to the second ejection port array are used. In order to obtain the first shift amount between the recording position by the ejection port belonging to the first ejection port array and the recording position by the ejection port belonging to the second ejection port array by ejecting ink. Recording the first pattern on the recording medium,
While performing scanning in the forward direction, ink is ejected using only the ejection ports belonging to the first ejection port array located on the leading side in the forward direction, and while scanning in the backward direction is performed. By ejecting ink using only the ejection ports belonging to the second ejection port array located on the head side in the return path direction, the ejection ports belonging to the first ejection port array in the scanning in the forward direction Recording on the recording medium a second pattern for acquiring a second shift amount between the recording position by the recording head and the recording position by the ejection ports belonging to the second ejection port array in the backward scanning. ,
The first ejection port array and the second ejection port at the time of scanning in the same scanning direction based on the first shift amount acquired using the first pattern recorded on the recording medium The first ejection timing adjustment value for correcting the recording position along the scanning direction by the ejection ports belonging to the column is obtained, and obtained using the second pattern recorded on the recording medium. Based on the second shift amount , a first position for correcting the recording position along the scanning direction by the first ejection port array and the ejection ports belonging to the second ejection port array at the time of scanning in different scanning directions. 2 discharge timing adjustment values are obtained, and the first discharge timing adjustment value obtained by using the first discharge timing adjustment value and the second discharge timing adjustment value is used for the first discharge port array. Outward way by the outlet Write adjustment method characterized by having a timing of discharge in the scan of the step of adjusting the timing of the discharge in the backward direction of the scan. A first ejection port array in which a plurality of ejection ports that communicate with a common liquid chamber for supplying ink and that eject ink are arranged on one side of the common liquid chamber; and the first liquid ejection chamber sandwiching the common liquid chamber A discharge means including a second discharge port array formed by arranging a plurality of the discharge ports communicating with the common liquid chamber along the first discharge port array on the opposite side to the first discharge port array; A plurality of recording heads provided as a first ejection unit corresponding to one color ink and a plurality of second ejection units corresponding to a second color ink different from the first color; A recording adjustment method in an inkjet recording apparatus that records an image on a recording medium by ejecting ink while scanning in the forward direction and the backward direction intersecting the direction in which the ejection ports are arranged in the ejection port array,
While performing scanning in the forward direction, only the discharge ports belonging to the first discharge port array located on the leading side in the forward direction of each of the first discharge unit and the second discharge unit are used. By ejecting ink, the recording position by the ejection ports belonging to the first ejection port array of the first ejection means in the forward scan and the first ejection port of the second ejection means Recording a pattern on the recording medium for acquiring a deviation A from a recording position by an ejection port belonging to a row;
The first ejection unit and the second ejection unit at the time of scanning in the forward direction based on the deviation amount A acquired using the pattern recorded on the recording medium. An ejection timing adjustment value for correcting the recording position along the scanning direction of the recording head by each ejection port belonging to the ejection port array is acquired, and a plurality of ejection units from the plurality of ejection units are acquired by the acquired ejection timing adjustment value . And a step of adjusting the timing of ink ejection.

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