Recording device

Abstract

To provide a recording apparatus capable of inhibiting accumulation of scorch caused by ink containing resin particulates associated with preliminary discharge.SOLUTION: A recording apparatus includes: a recording head for discharging ink to a recording medium; preliminary discharge control means for making the recording head perform preliminary discharge; and recovery control means for performing recovery processing of the recording head depending on the number of times of the preliminary discharge when executing the preliminary discharge.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a recording apparatus. [Background technology]

[0002] There is known a recording device that records an image on a recording medium by ejecting ink while scanning a recording head relative to the recording medium in a scanning direction. Some recording devices eject a small amount of ink at a predetermined location at certain time intervals, regardless of the recording data, which is called "intra-page preliminary ejection" or "preliminary ejection" in order to always maintain an appropriate ink ejection state. In recent years, various types of recording media and inks are used in recording devices to record on a variety of records, and for example, inks containing resin particles are used to improve color development, glossiness, and fixability to the recording medium. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-361889 A Summary of the Invention [Problem to be solved by the invention]

[0004] In ink containing such resin particles, the resin particles may accumulate as kogane on the recording element that ejects the ink to each nozzle. The accumulation of kogane is more likely to occur in a recording element that does not have recording data and performs preliminary ejection without ejection during recording, compared to a recording element that has recording data and performs ejection during recording and preliminary ejection. For this reason, it is important to grasp the number of preliminary ejections, estimate the degree of kogane accumulation, and suppress the accumulation of kogane. However, although Patent Document 1 can determine the amount of preliminary ejection of the recording head, it does not count the number of preliminary ejections during recording of the recording head, and therefore the state of kogane cannot be accurately estimated, and the accumulation of kogane due to preliminary ejection may not be suppressed. The present invention has been made in consideration of the above problems, and has an object to provide a recording device that can suppress the accumulation of burnt ink caused by ink containing resin fine particles that occurs during preliminary ejection. [Means for solving the problem]

[0005] In order to achieve the above object, a recording apparatus according to the present invention comprises: a recording head having an ejection heater for ejecting ink containing resin particles onto a recording medium; A preliminary ejection control means for causing the recording head to perform preliminary ejection; a recovery control means for causing the recording head to perform a recovery process of ejecting ink continuously a number of times after the end of a recording operation in accordance with the number of times the preliminary ejection has been executed; Equipped with The recovery process by the recovery control means Number of ejections from each ejection element is controlled by the preliminary ejection control means. From each ejection element The number of times of preliminary ejection is 100 times or more. the law of nature, The recovery control means controls the print head so as to perform the recovery process when the sum of the number of preliminary ejections and a value determined for each range of the number of ejections in the printing operation exceeds a predetermined number. . Effect of the Invention

[0006] According to the present invention, it is possible to provide a recording apparatus capable of suppressing the accumulation of burnt ink caused by preliminary ejection of ink containing resin particles. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram illustrating an inkjet recording apparatus according to an embodiment of the present invention; [Diagram 2] Nozzle arrangement diagram of a print head according to the present embodiment [Diagram 3] FIG. 1 is an enlarged cross-sectional view of an ejection port of a recording head according to an embodiment of the present invention. [Figure 4] FIG. 1 is a block diagram showing a configuration of an inkjet recording apparatus according to an embodiment of the present invention; [Diagram 5] FIG. 1 is a diagram showing a data processing process of an inkjet printing apparatus according to an embodiment of the present invention; [Figure 6]FIG. 1 shows a reflective optical sensor according to an embodiment of the present invention; [Figure 7] 1 is a flowchart showing a kogation accumulation suppression control according to a first embodiment. [Figure 8] FIG. 1 is a schematic diagram illustrating a case where ink containing resin particles is ejected from a recording element of an inkjet recording device according to an embodiment of the present invention; [Figure 9] FIG. 1 is a schematic diagram showing a case where only preliminary ejection of ink containing resin particles is repeated in a recording element of an inkjet recording device according to an embodiment of the present invention; [Figure 10] 10 is a flowchart showing a kogation accumulation suppression control according to a second embodiment. [Figure 11] Table showing the correspondence between the number of recording shots and the counter for the number of preliminary ejections in the second embodiment [Figure 12] FIG. 1 is a diagram of a discharge detection mechanism according to the present embodiment. [Figure 13] 10 is a flowchart showing control for performing preliminary ejection after the end of printing based on the ejection test results of only ink containing resin fine particles according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0009] <Recording device configuration> An inkjet recording apparatus according to this embodiment will be described with reference to the drawings.

[0010] 1 shows the external appearance of an inkjet recording device (hereinafter also referred to as a recording device or printer) according to this embodiment. This is a so-called serial scan type printer, which records an image by scanning a recording head in an X direction (scanning direction) perpendicular to a Y direction (transport direction) of a recording medium P.

[0011] The configuration of this inkjet recording device and an outline of the operation during recording will be described with reference to Fig. 1. First, a recording medium P is conveyed in the Y direction from a spool 101 holding the recording medium P by a conveying roller driven via gears by a conveying motor (not shown). Meanwhile, at a predetermined conveying position, a main scanning motor causes a carriage unit 102 to perform reciprocating scanning (reciprocating movement) in the forward direction in the +X direction and the return direction in the -X direction along a guide shaft 103 extending in the X direction. Then, during this scanning process, the timing is synchronized based on a position signal obtained by an encoder 106 in the main scanning direction, and a discharge operation is performed from the discharge openings of a recording head 105 that can be attached to the carriage unit 102, and recording is performed on the recording medium P.

[0012] In addition, the carriage unit 102 is fitted with a reflective optical sensor 107 that acquires the color development characteristics of the recording medium. As with the recording head 105, the timing is synchronized based on a position signal obtained by an encoder 106 during the reciprocating scanning process, and a detection signal corresponding to the position of the carriage unit 102 is processed. A carriage belt can be used to transmit the driving force from the main scanning motor to the carriage unit 102. However, instead of the carriage belt, other driving methods can be used, such as one that includes a lead screw that is rotationally driven by the main scanning motor and extends in the X direction, and an engagement portion that is provided on the carriage unit 102 and engages with a groove of the lead screw.

[0013] The fed recording medium P is sandwiched between a feed roller (not shown) and a pinch roller (not shown) and guided to a recording position (scanning area of ​​the recording head) on a platen 104. In a normal resting state, the face of the recording head 105 is capped, so prior to recording, the cap 108 is opened to make the recording head 105 or the carriage unit 102 ready for scanning.

[0014] After that, when data for one scan is accumulated in the buffer, the carriage unit 102 is scanned by the main scanning motor 420, and printing is performed as described above. In addition, when the carriage unit 102 is at the home position, the cap 108 covers the print head 105 to cap it. This prevents the ink in the ejection openings of the print head 105 from evaporating, and prevents the ink viscosity from increasing or the volatile components from evaporating and solidifying, causing ejection failure. The inside of the cap 108 is connected to a pump unit (not shown). The pump unit generates negative pressure as necessary, for example, when the print head 105 has an ejection failure, during suction recovery by joining the cap 108 and the print head 105, or when empty suction is performed to remove ink ejected into the cap 108. This allows the cap 108 to remove ink adhering to the vicinity of the ejection openings of the print head 105.

[0015] FIG. 2 shows an arrangement diagram of nozzles (ejection openings) in the print head 105 according to the present embodiment. The print head 105 is composed of non-fluorescent ink and fluorescent ink, and includes an ejection opening array 201 for ejecting black ink, an ejection opening array 202 for ejecting cyan ink, an ejection opening array 203 for ejecting magenta ink, and an ejection opening array 204 for ejecting yellow ink. Since the black ink, cyan ink, magenta ink, and yellow ink each contain only the corresponding coloring material, these inks are also referred to as non-fluorescent ink for the sake of simplicity in the following description. The print head 105 also includes an ejection opening array 205 for ejecting fluorescent ink. The fluorescent ink can be used to form an image on a print medium by dyeing resin particles with a fluorescent material. That is, in this specification, the fluorescent ink is an example of an ink containing a resin component such as resin particles, and the non-fluorescent ink is an example of an ink not containing a resin component. In this embodiment, the content concentration of resin particles in the fluorescent ink is 5%.

[0016] In the print head 105, these ejection port arrays are arranged in the order of ejection port arrays 201, 202, 203, 204, and 205 from the positive side to the negative side in the X direction. In these ejection port arrays 201, 202, 203, 204, and 205, 1280 ejection ports 200 that eject each ink are arranged in the Y direction (arrangement direction) at a density of 1200 dpi. In this embodiment, the amount of ink ejected from one ejection port 200 at one time is about 4.5 pl. These ejection port arrays 201, 202, 203, 204, and 205 are connected to ink tanks (not shown) that store the corresponding inks, and ink is supplied to them. In this embodiment, the print head 105 and the ink tanks may be configured to be separable from each other, or may be configured as an integrated unit.

[0017] 3 is an enlarged cross-sectional view of one ejection port 200 in the XY plane. In accordance with the print data received from the inkjet printing device, a drive pulse is applied to the ejection heater 300, whereby the ejection heater 300 is driven and generates heat. This thermal energy causes film boiling of the ink on the ejection heater 300, i.e., causes a state change in the ink to form bubbles, and the pressure of the bubbles generated at this time causes ink to be ejected from the ejection port 200, thereby performing a printing operation. The ejection heater 300 is sometimes referred to as a printing element.

[0018] 4 is a block diagram showing an example of the configuration of a recording device in this embodiment. The controller 400 as a main control unit has, for example, a CPU 401 in the form of a microcomputer, a ROM 402 for storing programs, required tables and other fixed data, and a RAM 403 in which an area for developing image data and an area for working are provided. The controller 400 also executes a process for adjusting the landing position, which will be described later. The process for adjusting the landing position sets an adjustment value for adjusting the landing position, and the adjustment value is used to adjust the landing position in the subsequent recording process. The controller 400 also functions as a preliminary ejection control unit that causes the recording head 105 to perform a preliminary ejection operation and a recovery control unit that causes the recording head 105 to perform a recovery process, as will be described later.

[0019] The host device 404 is a source of image data, and may be in the form of a computer that creates and processes data such as images related to recording, or in the form of a reader unit for reading images. Image data, other commands, status signals, etc. are transmitted to and received from the controller 400 via an interface (I / F) 405. The operation unit 406 is a group of switches that accepts instruction input by an operator, and has a power switch 407, a switch 408 for instructing the start of recording, and a recovery switch 409 for instructing the start of a predetermined recovery process such as a suction recovery operation for the recording head 105. In one example, the operation unit 406 may have a landing position adjustment start switch 410 for adjusting the landing position. In this embodiment, the start of recording, the recovery operation, and the landing position adjustment are performed by switches provided on the main body. However, they may be performed based on instructions from the host device 404.

[0020] The sensor group 411 is a sensor group for detecting the state of the recording apparatus, and includes a reflective optical sensor 107, a photocoupler 412 for detecting the home position, an ejection detection unit 450, and a temperature sensor 413 provided at an appropriate location for detecting the environmental temperature.

[0021] The head driver 414 is a driver that drives the ejection heaters 300 of the print head 105 in accordance with print data, etc. The head driver 414 includes a shift register that aligns the print data in accordance with the positions of the ejection heaters 300, a latch circuit that latches the data at appropriate timing, and a logic circuit element that operates the ejection heaters 300 in synchronization with a drive timing signal.

[0022] The print head 105 is provided with a sub-heater 418. The sub-heater 418 adjusts the temperature to stabilize the ink ejection characteristics. The sub-heater 418 may be formed on the print head substrate in the same manner as the ejection heater 300, or may be attached to the print head 105.

[0023] The main scanning motor driver 415 is a driver for driving the main scanning motor 420. As described above, the main scanning motor 420 is a motor used for causing the carriage unit 102 to perform reciprocating scanning (reciprocating movement) along the guide shaft 103. The sub-scanning motor driver 416 is a driver for driving the sub-scanning motor 421. The sub-scanning motor 421 is a motor used for transporting the recording medium P (moving it in the sub-scanning direction) via a transport roller. The recovery processing unit 517 performs recovery processing for maintaining a good ink ejection state in the recording head 105.

[0024] 5 is a flowchart explaining the image data processing process in this embodiment. Image data to be recorded by the inkjet recording apparatus 1 is created via application J101 of the host device 404. When recording, the image data created by application J101 is transmitted to the printer driver 500.

[0025] The printer driver 500 executes pre-processing J0002, post-processing J0003, gamma correction J0004, and binarization J0005 on the created image data. In the pre-processing J0002, color gamut conversion is performed to convert the color gamut of the display of the host computer 115 into the color gamut of the printer 1. By using a three-dimensional lookup table, the image data R, G, and B, in which R, G, and B are each expressed in 8 bits, are converted into 8-bit data R, G, and B within the color gamut of the printer. In the post-processing J0003, the colors that reproduce the converted color gamut are separated into the color gamut of the inks. A process is performed to obtain 8-bit data (image data) corresponding to the combination of inks for reproducing the colors represented by the 8-bit data R, G, and B within the print color gamut obtained in the pre-processing J0002. In the gamma correction J0004, gamma correction is performed on each of the 8-bit data (image data) obtained by color separation. The 8-bit data obtained in the post-processing J0003 is converted so that each piece of data corresponds linearly to the gradation characteristics of the inkjet recording device, and 8-bit data (corrected data) corresponding to the combination of inks is obtained. In the binarization process J0005, a quantization process is performed in which each piece of 8-bit data (corrected data) obtained in the gamma correction J0004 is converted to 1-bit data to generate binary data. Any quantization method such as a density pattern method, a dither method, an error diffusion method, etc. can be used for this quantization process. The data generated in this manner is supplied to the inkjet recording device 1.

[0026] In the mask data conversion process J0008, the binary data created in the binarization process J0005 is converted into print data representing whether or not to eject ink, using a mask pattern stored in ROM 402. This mask pattern is configured by arranging print permitting pixels that permit ink ejection and non-print permitting pixels that do not permit ink ejection in a specific pattern. The mask pattern used in the mask data conversion process J0008 is stored in advance in a specified memory within the inkjet printing device.

[0027] For example, a mask pattern can be stored in ROM 402, and the mask pattern can be used to convert the data into print data by CPU 401. The print data obtained by the mask data conversion process is supplied to head driver 414 and print head 105. Based on this print data, ink is ejected onto print medium P from each ejection port arranged in print head 105. Based on the print data created by the above-described process, the drive of each motor, print head, etc. is controlled to perform the printing operation.

[0028] In addition, the registration adjustment for fluorescent ink and non-fluorescent ink will be described. Figures 6(a) and 6(b) are schematic diagrams for explaining the reflective optical sensor 107 that acquires the color development characteristics of the recording medium shown in Figure 1.

[0029] As described above, the reflective optical sensor 107 is attached to the carriage unit 102, and its measurement area is located downstream in the transport direction (Y direction) from the recording surface of the recording head 105. The bottom surface of the reflective optical sensor 107 is disposed so as to be at the same position as the bottom surface of the recording head 105 or higher.

[0030] 6(a) shows a cross-sectional view of the reflective optical sensor 107. It is provided with a light emitting unit 601 realized by a visible LED of red, green, blue, etc., and a light receiving unit 602 realized by a photodiode. Light 603 emitted from the light emitting unit 601 is diffusely reflected at a detection spot 605 on the recording medium P, and the diffusely reflected light 604 can be detected by the light receiving unit 602.

[0031] 6(b) shows a detection spot 605 by the reflective optical sensor 107. The detection spot 605, where light 603 emitted from the light emitting unit 601 is diffusely reflected by the recording medium P, is a circle with a diameter of about 3 mm. A detection signal (analog signal) of the reflected light 604 is transmitted to a control circuit on an electric board of the recording device via a flexible cable (not shown), and is converted into a digital signal by an A / D converter in the control circuit.

[0032] When measuring the color development characteristics of an adjustment pattern for adjusting the landing position, which will be described later, conveyance of the recording medium P in the sub-scanning direction and movement of the carriage unit 102, to which a reflective optical sensor 107 is attached, in the main scanning direction are alternately performed. In this way, the reflective optical sensor 107 detects the density of the adjustment pattern recorded on the recording medium P as optical reflectance, in synchronization with the timing based on the position signal obtained by the encoder 106.

[0033] When light is irradiated onto an adjustment pattern formed on the recording medium surface, it is possible to detect the level of reflection intensity that reflects the density of the adjustment pattern. The reflection intensity is strong on a white recording medium surface, and the reflection intensity is weaker for adjustment patterns with higher densities. When fluorescent ink emits fluorescence, the reflective optical sensor 107 in Figure 6(a) receives all wavelengths, including the light-emitting area, in response to density changes in the density method, which is a fine adjustment of registration, so the sensor's read signal value becomes smaller.

[0034] For this reason, the influence of the sensor reading error becomes large, making it difficult to adjust the registration using the fine-adjustment density method that detects density changes. However, the coarse-adjustment distance detection method detects the boundary position where the read signal value of the paper white part and the read signal value of the patch part switch. Therefore, the reflective optical sensor 107 in FIG. 6(a) receives all wavelengths including the light-emitting area, so the S / N ratio can be sufficiently ensured even with the read signal value of the sensor. Registration adjustment for fluorescent ink is performed by carrying out the processes described in S1501, S1502, and S1503 in FIG. 17 of the patent document, JP2013-240991A.

[0035] For fluorescent ink, which is resistant to visual unevenness caused by variations in landing position, registration adjustment can be performed only by the coarse distance detection method. On the other hand, non-fluorescent ink is not affected by light emission, so after performing the coarse distance detection method, the process described in S1501 to S1505 in FIG. 17 of JP 2013-240991 A, which performs fine adjustment of the density method, is performed. In addition, in the registration adjustment for non-fluorescent ink, the even-odd inter-row correction and AB inter-row correction between nozzle rows, which have a relatively small amount of deviation in the printing position, may be performed only by the fine adjustment of the density method.

[0036] <First Example> Next, the burnt prevention control according to the first embodiment will be described with reference to the flowchart of Fig. 7. The process shown in Fig. 7 is realized by the CPU 401 of the controller 400 loading a program stored in the ROM 402 into the RAM 403 and executing the program.

[0037] When the controller 400 receives print data from the host device 404 via the IF 405, in S701, the controller 400 controls the conveying motor to feed the print medium, and in S702, performs a print operation for one scan. In the print operation, print ejection, which is ejection involved in printing an image, is performed. Next, the controller 400 advances the process to S703, and determines whether or not a timer A, which indicates the length of time during which preliminary ejection is not performed, exceeds a threshold value Ath. For example, the threshold value Ath may be one second. If the timer A exceeds the threshold value Ath (Yes in S703), the controller 400 advances the process to S704. If the timer A does not exceed the threshold value Ath (No in S703), the controller 400 advances the process to S705. Next, in S704, the controller 400 turns on the preliminary ejection flag. In S705, the controller 400 determines whether or not the preliminary ejection flag is ON. If the preliminary ejection flag is ON (Yes in S705), the controller 400 advances the process to S706. If the prefire flag is not ON (No in S705), the controller 400 advances the process to S708. In S706, the controller 400 controls the print head 105 to execute prefire, and advances the process to S707. Prefire is, for example, execution of less than 20 ejections per page that are not related to printing.

[0038] In S707, since preliminary ejection was performed in S706, counter B, which indicates the number of times preliminary ejection has been performed, is incremented to B=B+1, the preliminary ejection flag is set to OFF, and timer A is reset. In S708, it is determined whether recording has ended. If recording has ended, the process proceeds to S709. If recording has not ended, that is, if there is still an image to be recorded, the controller 400 returns the process to S702 and performs recording for one scan. Next, the controller 400 proceeds to S709 and ejects the recording paper.

[0039] As described above, by periodically performing preliminary ejection while performing print scanning, a good state can be maintained at all times even when there is no print image, and when a print image appears during print scanning, the image can be output without any problems.

[0040] Here, the accumulation of kogation caused by ink containing resin particles will be described with reference to Figures 8 and 9. Figure 8 is a schematic diagram showing the state of the ejection heater 300 when ink containing resin particles is ejected.

[0041] A characteristic of ink containing resin particles, such as the fluorescent ink of the ejection port array 205, is that the resin particles themselves may become partially unstable due to thermal shock when bubbles are generated or eliminated by driving the ejection heaters 300.

[0042] At that time, the unstable resin particles may bond with each other or may adhere to the heater, as shown in 801. On the other hand, even if the resin particles adhere to the heater, they may detach as shown in 802 due to the thermal shock caused by the foam disappearance due to discharge. During continuous discharge, the particles repeat bonding and detaching as shown in Fig. 8, making it possible to discharge while maintaining a certain equilibrium state.

[0043] On the other hand, Fig. 9 is a schematic diagram showing the state of the ejection heater 300 when only preliminary ejection of ink containing resin particles is performed. For example, when the image of the fluorescent ink 45 is not included in the recording image, the fluorescent ink 45 is not ejected in the recording ejection during recording, so the ejection heater 300 corresponding to the fluorescent ink 45 performs only preliminary ejection. Preliminary ejection is a control for ejecting ink to suppress drying of the ink, and ejects a smaller amount of ink compared to normal ejection. In this embodiment, ten shots are used. In preliminary ejection, a relatively small amount of ink is ejected, so that the thermal shock when bubbles disappear due to ejection is small, and the effect of the detachment of the resin particles on the heater is smaller than that of recording ejection.

[0044] For this reason, when ink containing resin particles is not ejected during printing but a small amount of preliminary ejection is repeated, the resin particles themselves adhere to the ink during pauses in the printed image, and there is little opportunity for the resin particles to detach with only a small amount of preliminary ejection. For this reason, as shown in Fig. 9, the resin particles may gradually adhere to the ejection heater 300 and accumulate as kogane 901. When kogane accumulates, the energy used during ejection is inhibited by the kogane, and the energy with which the ink is ejected is weakened, reducing the amount of ink ejected and possibly deteriorating the printed image.

[0045] In this embodiment, the degree of kogation accumulation is estimated by counting the number of times preliminary ejection is performed, and a recovery process is performed when the number of times preliminary ejection is performed exceeds a threshold value. The recovery process is, for example, continuous ejection into the cap 108 multiple times, such as 1000 times or more, for example 10000 times, after the end of recording. The recovery process may include suctioning the nozzle with the cap 108, or may include wiping. The recovery process promotes the separation of resin particles, reduces the kogation accumulation, and makes it possible to recover to an equilibrium state as shown in FIG. 8. Therefore, in S710, it is determined whether counter B, which indicates the number of times preliminary ejection is performed, exceeds a threshold value Bth. Here, Bth is 10000 times.

[0046] If counter B exceeds threshold value Bth, proceed to S111. If counter B does not exceed threshold value Bth, end the process.

[0047] In S711, recovery processing is performed on the print head 105 after printing has finished. In the recovery processing, 10,000 shots are continuously ejected as described above, which can further promote the removal of kogation. In S712, counter B is reset and the processing ends. As described above, in a printing device equipped with ink containing resin fine particles, the accumulation of kogation caused by the resin fine particles can be estimated based on the number of times preliminary ejection has been performed, and the recovery processing is periodically performed to suppress the accumulation of kogation.

[0048] <Second Example> In the first embodiment, when the number of times the preliminary ejection is performed exceeds a threshold value, recovery processing is performed uniformly after the end of recording, regardless of the recording ejection. However, if the recording image includes an image of ink containing resin particles, the kogation may be removed by the recording ejection, making it possible to suppress the accumulation of kogation. In the second embodiment, control for executing a recovery operation after the end of recording based additionally on the number of ejections in the recording ejection will be described. Note that the same reference numerals are used for configurations, processes, and functions similar to those in the first embodiment, and descriptions thereof will be omitted.

[0049] FIG. 10 is a flowchart in the second embodiment, and the process of S1007 will be described in detail as a difference from the first embodiment.

[0050] In S1007, because preliminary ejection was performed in S706, the controller 400 calculates value C based on the number of ejections of the ejection heater 300 during printing ejection in addition to counter B indicating the number of preliminary ejections, sets the preliminary ejection flag to OFF, and resets timer A.

[0051] Here, the calculation of the value C based on the number of ejections in the printing ejection will be described with reference to the table in FIG.

[0052] The number of print shots in the table shown in Fig. 11 is calculated from the print data created by the process in Fig. 6. For example, when performing one preliminary ejection for each print scan (print ejection), control is performed based on the average number of print shots (average number of ejections) per print scan.

[0053] When the number of ejections in one printing scan is 3,200,000, there are 1,280 ejection ports per row of the print head 105, so an average of 2,500 ejections are performed. Similarly, when the number of ejections in one printing scan is 6,400,000, an average of 5,000 ejections are performed for each ejection heater 300. Similarly, when the number of ejections in one printing scan is 12,800,000, an average of 10,000 ejections are performed for each ejection heater 300. When the number of ejections is 0, the average is 0.

[0054] When the average number of ejections in print ejection is 0 or more and less than 2500, kogation adheres and accumulation progresses as in the first embodiment, so the value C is set to C+1. When the average number of ejections is 2500 or more and less than 5000, the balance between ejection during print scanning and the removal of kogation is balanced, so the value C is set to C. When the average number of ejections in print ejection is 5000 or more and less than 10000, the effect of removing kogation due to ejection during print scanning is obtained, and the degree of kogation accumulation is reduced, so the value C is set to C-1. Therefore, the value C can be a negative value.

[0055] When the average number of ejections in the printing ejection is 10,000 or more, the ejection during the printing scan is the same number of ejections as the number of continuous ejections in the recovery process in S111 in the first embodiment. In other words, when the average number of ejections in one printing ejection is 10,000, the same burnt reduction effect as the recovery process after the end of printing in the first embodiment is obtained. Therefore, it is assumed that the same burnt reduction effect as that obtained by resetting counter B in S712 has already been obtained, so counter B is reset and value C is set to 0.

[0056] Then, in S1010, if it is determined that the sum of counter B and value C exceeds threshold value Bth, the process proceeds to S711 to execute recovery processing after the end of printing. Next, in S1012, value C determined based on the number of preliminary ejections B and the number of ejections in the printing scan is reset to 0.

[0057] As described above, by taking into consideration both the effect of reducing kogation according to the number of ejections in one recording ejection and the effect of kogation accumulation according to preliminary ejection, it is possible to more accurately estimate the degree of kogation accumulation and perform recovery processing at an appropriate timing.

[0058] <Other Examples> As another example, a control for performing recovery processing after recording in this embodiment based on the ink discharge inspection result will be described. In this example, the recording device 1 is provided with a discharge detection unit 450 as an optical sensor that determines whether ink has been discharged. The discharge detection unit 450 includes a light emitting element 1201 and a light receiving element 1202 that are arranged at a position away from the discharge port in order to detect the ink discharge state, as shown in FIG.

[0059] The ejection detection unit 450 is attached below the carriage scanning, and ejects ink above the sensor after the carriage moves. The ejection detection unit 450 keeps the output of the light emitting element 1201 constant, and judges that ejection has occurred when the light receiving intensity of the light receiving element 1202 changes, and that ejection has not occurred when the light receiving intensity does not change. In one example, it may be judged that ejection has occurred when the light receiving intensity of the light receiving element 1202 is smaller than a predetermined threshold, and that ejection has not occurred when the light receiving intensity is equal to or greater than the predetermined threshold.

[0060] In the case of ink containing resin microparticles, if the ink ejection speed decreases due to the accumulation of burnt material, the ink droplets may not reach the detection range of the ejection detection unit 450, and the detection result may be determined as non-ejection.

[0061] Hereinafter, with reference to the flowchart in FIG. 13, a description will be given of control of recovery after the end of recording according to this embodiment, which is performed based on the ejection test results of ink containing resin particles.

[0062] In S1301, a discharge test is performed. The discharge test is performed periodically after recording is completed, or when the user selects cleaning, etc. In one example, while the recording apparatus 1 is performing preliminary discharge, it may be determined whether or not ink discharged in the preliminary discharge has been detected.

[0063] In S1301, the number of nozzles determined to be non-ejecting by the ejection detection unit 450 is counted as the number of non-ejecting nozzles N. For example, ejection of ink containing resin fine particles is performed in order from each ejection port 200, and the number of nozzles that have been detected as ejecting by the ejection detection unit 450 is subtracted from the total number of ejection ports for the ink containing resin fine particles, thereby counting the number of non-ejecting nozzles N.

[0064] In S1302, it is determined whether the number N of the ejection ports 200 that were determined to be non-ejection, that is, the number N of the ejection ports 200 that were not detected to have ejected despite having been ejected, exceeds a threshold value Nth. Here, the threshold value Nth is set to 10. If the number N of the ejection ports 200 that were determined to be non-ejection exceeds the threshold value Nth (Yes in S1302), the process proceeds to S1303, and if it does not exceed the threshold value Nth (No in S1302), the process ends. In S1303, a recovery process is performed. For example, in S1303, the nozzle is suctioned. Even if the ink in the liquid chamber or the nozzle is not filled, ink is supplied by this operation to fill the ink in the liquid chamber or the nozzle, and the ejection port can be restored. In addition, in S1303, continuous ejection may be performed. As a result, even if kogation accumulation due to resin fine particles occurs, it is possible to promote the removal of kogation and reduce kogation accumulation. In addition, wiping is performed in S1303. As a result, even if paper dust or the like adheres to the surface of the print head 105 and inhibits ejection, the paper dust can be removed and the ejection speed can be restored.

[0065] As described above, in the case of ink containing resin microparticles, it is possible to determine whether ejection has been detected, and by executing a recovery process if it is determined that ejection has not been detected, ejection defects of the recording element can be improved.

[0066] 13 can also be applied to ejection elements that eject ink that does not contain resin particles. In this case, in S1303, suction and wiping of the nozzles are performed, but the type of recovery process may be changed depending on the ink to be ejected, such as not performing continuous ejection. This allows the controller 400 to execute recovery processes appropriate to the type of ink.

[0067] In the present embodiment, the ink is ejected while the print head scans in the width direction. However, the present invention can also be applied to a printing apparatus that uses a print head having a length longer than the width direction of the printing medium, and ejects ink from the print head while conveying the printing medium only once in a direction intersecting the width direction to print an image.

[0068] In another embodiment, the controller 400 may control the number of ejections in the recovery process after the end of recording to be increased as the temperature increases, or may control the number of preliminary ejections after the end of recording to be more frequent, depending on the temperature of the recording device during recording. For example, the controller 400 may appropriately change the control such as the threshold value Ath corresponding to the execution cycle of the preliminary ejection, the threshold value Bth for the number of preliminary ejections, and the value C corresponding to the number of ejections in the recording ejection of S1007, depending on the output of the temperature sensor 413. That is, the controller 400 may execute the recovery process more frequently or may set the contents of the recovery process depending on the temperature measured by the temperature sensor 413, for example.

[0069] In another embodiment, for example, the controller 400 may obtain the execution interval of the recovery process depending on the length of time that the recovery process is not being executed, and the longer the execution interval, the more the number of ejections in the recovery process may be increased, or the control may be changed to execute the recovery process more frequently.

[0070] In another embodiment, the control may be changed so that the number of ejections in the recovery process is increased as the cumulative number of ejections of the print head increases, or the recovery process is executed more frequently.

[0071] In addition, in this embodiment, the resin fine particle content concentration is described as 5%. However, in order to make a thick ink, the resin fine particle content concentration may be increased to a high concentration such as 10%. In that case, the resin fine particles may become more unstable due to thermal shock caused by foaming or defoaming caused by driving the ejection heater 300 during ejection. Therefore, depending on the resin fine particle content concentration, particularly the higher the concentration, the more the ejection count in the recovery process may be increased or the control may be changed so that the recovery process is executed more frequently.

[0072] In addition, in the present embodiment, when the number of preliminary ejections is equal to or greater than a predetermined number, the recovery process is performed after the end of the printing operation. However, in one example, the recovery process may be performed after one scan, after printing on one sheet of printing medium is completed, or after one printing job is completed.

[0073] The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

[0074] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0075] 102: carriage, 105: print head, 300: print element, 400: controller

Claims

1. A recording device, comprising: a recording head having an ejection heater for ejecting ink containing resin particles onto a recording medium; A preliminary ejection control means for causing the recording head to perform preliminary ejection; a recovery control means for causing the recording head to perform a recovery process of ejecting ink continuously a number of times after the end of a recording operation in accordance with the number of times the preliminary ejection has been executed; Equipped with the number of ejections from each ejection element in the recovery process by the recovery control means is 100 times or more the number of preliminary ejections from each ejection element by the preliminary ejection control means, The recovery control means controls the print head to perform the recovery process when the sum of the number of preliminary ejections and a value determined for each range of the number of ejections in the printing operation exceeds a predetermined number.

2. a cap that covers the recording head and absorbs ink ejected from the recording head; 2. The printing apparatus according to claim 1, wherein the recovery process includes an operation of ejecting ink from the print head to the cap.

3. 3. The recording apparatus according to claim 1, wherein the end of the recording operation is when recording on one recording medium is completed.

4. 3. The recording apparatus according to claim 1, wherein the end of the recording operation is the end of one recording job.

5. 5. The printing apparatus according to claim 1, wherein the recovery control means controls the print head so as to perform the recovery process every time the number of preliminary ejections reaches a predetermined number.

6. 2. The recording apparatus according to claim 1, wherein the value is a first value when the number of ejections in the recording operation is within a first number range, and is a second value smaller than the first value when the number of ejections is within a second number range that is greater than the first number range.

7. 7. The recording apparatus according to claim 6, wherein the recovery control means resets the number of preliminary ejections to zero when the number of ejections in the recording operation is greater than the second number range.

8. 8. The recording apparatus according to claim 1, wherein the recovery control unit resets the number of preliminary ejections to 0 when the recovery process is performed.

9. 9. The recording apparatus according to claim 1, wherein the preliminary ejection control means controls the recording head to perform the preliminary ejection when a time during which the preliminary ejection is not performed during a recording operation exceeds a predetermined time.

10. 10. The recording apparatus according to claim 1, wherein the recording head includes a heater that generates heat when a driving pulse is applied thereto.

11. A conveying means for conveying the recording medium; a scanning means for scanning the recording head in a direction intersecting with a conveying direction of the conveying means; 11. The recording apparatus according to claim 1, further comprising:

12. a detection unit for detecting ink ejected from the recording head at a predetermined position away from the recording head; 12. The recording apparatus according to claim 1, wherein the recovery control means determines whether or not to execute the recovery process based on a detection result of the detection means.

13. a temperature sensor for measuring an internal temperature of the recording device; 2. The recording apparatus according to claim 1, wherein the recovery control means sets the predetermined number of times to a smaller number as the temperature measured by the temperature sensor increases.

14. a temperature sensor for measuring an internal temperature of the recording device; 3. The recording apparatus according to claim 1, wherein the recovery control means increases the number of ejections in the recovery process as the temperature measured by the temperature sensor increases.

15. 2. The recording apparatus according to claim 1, wherein the recovery control means sets the predetermined number of times to a smaller value as the time during which the recovery process is not executed becomes longer.

16. 3. The recording apparatus according to claim 1, wherein the recovery control unit increases the number of ejections in the recovery process as the time during which the recovery process is not executed increases.

17. 2. The recording apparatus according to claim 1, wherein the recovery control means sets the predetermined number of times to a smaller number as the concentration of a resin component contained in the ink increases.

18. 3. The recording apparatus according to claim 1, wherein the recovery control unit increases the number of ejections in the recovery process as the concentration of the resin component contained in the ink increases.

19. 19. The printing apparatus according to claim 1, wherein the recovery control means causes each ejection element to eject ink continuously 1000 times or more in the recovery process.

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