JP2011167921A - Ink jet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet recorder which performs a recording by discharging an ink containing color material and the treatment liquid for reacting with the ink and prevents the occurrence of solidification while leaving the ink and the treatment liquid adhered to a recording head. <P>SOLUTION: The ink jet recorder has the recording head for discharging the ink and treatment liquid. The ink jet recorder has a recovering mechanism for applying a recovery processing to the recording head for performing at least either one of the operation for suppressing the thickening of the ink and treatment liquid stored in the recording head and the operation for removing the ink and treatment liquid adhered to the recording head. The ink jet recorder has the first recording mode for discharging an ink from an ink discharging port and making a record with accompanying the discharge of treatment liquid, and the second recording mode for discharging an ink and making a record without causing the discharge of liquid treatment from a treatment liquid discharging port. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that performs recording using a recording head having a plurality of ejection openings for ejecting ink.

  In recent years, with the widespread use of information equipment, recording devices that are peripheral equipment are also rapidly spreading. Among them, the ink jet recording apparatus is rapidly popular because it can be easily downsized and has a relatively simple color recording.

  However, when recording by the ink jet recording apparatus, ink mist that is smaller than the main droplet is generated, and this may float between the recording head and the recording medium. Further, when the ejected ink droplets fly while pulling the surrounding air, an air flow is generated between the recording head and the recording medium, and this may be reflected by the recording medium to generate an upward air flow. When the ink mist is wound up with an upward air flow between the recording head and the recording medium, a phenomenon may occur in which the ink mist adheres to the surface of the recording head. If the ink mist adheres to the vicinity of the ejection port and is left as it is for a long time, the adhering ink mist thickens on the surface of the recording head and solidifies. When the ink mist is solidified, this may block the ejection port, resulting in non-ejection in which the ink is not ejected or misalignment in which the ink is not ejected in an appropriate direction.

  In order to suppress these occurrences, in the ink jet recording apparatus, preliminary discharge may be performed to discharge the liquid droplets that are not involved in recording outside the recording area to suppress the increase in viscosity near the discharge port. Also, wiping may be performed in which ink attached to the surface of the recording head is wiped with a wiper. Patent Document 1 discloses an ink jet recording apparatus that changes the timing of wiping for wiping the surface of a recording head in accordance with the type of ink that is ejected.

JP 2006-240177 A

  However, in an ink jet recording apparatus, in order to improve the scratch resistance and color developability of ink droplets that have landed on a recording medium, an ink jet that discharges ink containing a coloring material and a treatment liquid onto the recording medium. There is a recording device. In such an ink jet recording apparatus, the ink and the treatment liquid come into contact with each other by causing the treatment liquid to be ejected onto the recording medium together with the ink, thereby causing a chemical reaction between them. Thereby, the ink is solidified on the recording medium, and the scratch resistance of the ink is improved. As described above, when the processing liquid is ejected from the recording head together with the ink droplets, the processing liquid may become a fine mist and float between the recording head and the recording medium. At this time, the ink droplets and the processing liquid react on the surface of the recording head, and the ink droplets and the processing liquid may solidify there, which may affect the landing accuracy of the ink droplets that are subsequently ejected.

  In the above-described ink jet recording apparatus, the timing at which wiping is performed is adjusted according to the type of ink. However, there is no mention of the case where recording is performed by ejecting ink having a color material and a treatment liquid that reacts in contact with the ink.

  Accordingly, the present invention has been made in view of the above circumstances, and recording is performed by ejecting ink containing a coloring material and a treatment liquid for reacting with the ink, and the ink and the treatment liquid adhere to the recording head. An object of the present invention is to provide an ink jet recording apparatus which can be prevented from solidifying as it is.

  The ink jet recording apparatus of the present invention includes a recording medium having an ink discharge port that discharges ink containing a color material and a treatment liquid discharge port that discharges a treatment liquid containing a component that is solidified by contact with the ink. Recovering the recording head for at least one of suppressing the increase in the viscosity of the head and the ink and processing liquid stored in the recording head or removing the ink and processing liquid adhering to the recording head A recovery mechanism for performing processing, and recording is performed by ejecting ink from the ink ejection port onto the recording medium, and processing liquid is ejected from the processing liquid ejection port and ejected from the ink ejection port. In an ink jet recording apparatus capable of solidifying ink landed on a recording medium by bringing it into contact with ink, the treatment liquid from the treatment liquid discharge port A first recording mode in which recording is performed by ejecting ink from the ink ejection port, and ink is ejected from the ink ejection port without ejection of the processing liquid from the processing liquid ejection port. The second recording mode in which recording is performed by discharging the ink and the frequency at which the recovery processing is performed when recording is performed in the first recording mode are the recovery processing when recording is performed in the second recording mode. Recovery processing control means for controlling the timing at which the recovery processing is performed so as to be higher than the frequency at which the processing is performed.

  According to the present invention, when recording is performed by discharging ink containing a color material and a treatment liquid that reacts with the ink, it is possible to suppress solidification of the ink and the treatment liquid on the surface of the recording head. In addition, the ink droplet landing accuracy is kept high, and the quality of the recorded image is kept high.

FIG. 2 is a plan view schematically showing a main part of the ink jet recording apparatus according to the embodiment of the present invention. FIG. 2 is a schematic perspective view showing a carriage on which a recording head is mounted in the ink jet recording apparatus of FIG. 1. FIG. 2 is a block diagram of a control system of the ink jet recording apparatus of FIG. 1. FIG. 2 is an explanatory diagram for explaining an air flow generated between a recording head and a recording medium when high duty recording is performed by the ink jet recording apparatus of FIG. 1. FIG. 2 is an explanatory diagram for explaining an air flow generated between a recording head and a recording medium when recording with a low duty is performed by the ink jet recording apparatus of FIG. 1. 3 is a flowchart illustrating a control flow when recording is performed by the ink jet recording apparatus of FIG. 1. 3 is a table showing coefficients multiplied by the number of ink ejections and the number of treatment liquid ejections in the dot count when recording is performed by the ink jet recording apparatus of FIG. 1. 6 is a table showing coefficients that are multiplied by the number of ink ejections and the number of treatment liquid ejections in the dot count when recording is performed by the inkjet recording apparatus of the comparative example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a plan view schematically showing an ink jet recording apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a recording apparatus main body provided with various mechanism units including a recording medium transport system unit (not shown). The ink jet recording apparatus 1 in the present embodiment has a recording head 3. The recording head 3 is formed by the carriage 2 so as to be able to scan in the main scanning direction, and is a serial type ink jet recording apparatus. Further, the recording head 3 has an ink ejection port for ejecting ink containing a color material, and a processing liquid ejection port for ejecting a processing liquid containing a component that solidifies by contact with the ink. Yes. The serial type inkjet recording apparatus 1 intermittently transports a recording medium in the Y direction by a transport system unit. The Y direction (sub-scanning direction), which is the conveyance direction of the recording medium, intersects the X direction (main scanning direction) in which the recording head 3 performs scanning. In the present embodiment, the conveyance direction of the recording medium is orthogonal to the main scanning direction of the recording head. Scanning in the main scanning direction by the recording head and conveyance of the recording medium are alternately repeated to perform a recording operation on the recording medium.

  A recording head 3 is detachably mounted on the carriage 2. When the carriage 2 reciprocates along the X direction with the recording head 3 mounted thereon, the recording head 3 performs scanning. Specifically, the carriage 2 is supported so as to be movable along a guide shaft 4 disposed along the X direction. The carriage 2 is fixed to an endless belt 5 that moves substantially parallel to the guide shaft 4. The endless belt 5 is reciprocated by the driving force of the carriage motor (CR motor), thereby reciprocating the carriage 2 in the X direction.

  FIG. 2 is a perspective view schematically showing the recording head 3 mounted on the carriage 2 according to the embodiment of the present invention. In the recording head 3, as shown in FIG. 2, a plurality of discharge ports 20a formed on the discharge port forming surface 21 and a plurality of liquid paths (not shown) formed corresponding to the individual discharge ports 20a. And a common liquid chamber (not shown) for supplying ink to the plurality of liquid paths. In the present embodiment, a plurality of recording heads 3 are mounted on the carriage 2. Although FIG. 2 shows a state in which three separate recording heads 3 are provided on the carriage 2, the present invention is not limited to this. Three or more recording heads may be attached to the carriage, or one or two recording heads may be attached to the carriage. In each recording head 3 of the present embodiment, 1280 ejection ports 20 are arranged at a density of 1200 dpi (dots / inch) of the same color ink in the Y direction, which is the sub-scanning direction, and the carriage 2 is It reciprocates in the X direction, which is the main scanning direction. An ejection port for ejecting ink containing a color material is provided at 20c in FIG. 2, and an ejection port for ejecting the treatment liquid is provided at 20d as both ends. In this way, recording is performed by ejecting ink onto the recording medium from the ejection port 20c serving as the ejection port for ink, and processing liquid can be ejected from the ejection port 20d serving as the ejection port for processing liquid. Yes. In the present embodiment, the processing liquid contains a component capable of solidifying the ink and aggregating the color material component of the ink by contacting the recording ink discharged from the discharge port 20c. ing. Here, the treatment liquid solidifies the ink in order to improve the scratch resistance of the ink landed on the recording medium. In the present embodiment, when a processing liquid is used at the time of image formation, it is preferable to discharge ink containing a coloring material after discharging the processing liquid. For this reason, in order to form an image by ejecting ink in both directions of reciprocation of the carriage 2, the ejection port array is provided with ejection ports 20d for ejecting the processing liquid at both ends in the scanning direction. Is preferred. However, even if an ejection port for ejecting the processing liquid is provided only at one end, it is possible to perform recording so that ink is ejected after the processing liquid is ejected by ejecting the processing liquid onto the recording medium in advance. Is possible. Further, if the recording head is limited to be used for unidirectional recording in which only one of forward and backward scanning among reciprocating scanning is used, the processing liquid is discharged only to one end. A discharge port may be provided.

  Further, an ejection port for ejecting the processing liquid may be formed so that the processing liquid is ejected so as to cover the landed ink after ejecting the ink containing the coloring material. By performing recording with such a recording head, the processing liquid comes into contact with the ink discharged onto the recording medium, and the processing liquid can solidify the ink and aggregate the ink.

  In each liquid path of the recording head 3, energy generating elements that generate ejection energy for ejecting ink from the ejection ports 20 are arranged. In this embodiment, an electrothermal converter that heats the ink locally to cause film boiling and ejects the ink by the pressure is used as the energy generating element. However, the present invention is not limited to this, and it is also possible to eject ink from the recording head using an electromechanical conversion element such as a piezo element. In the following description, the discharge port 20 and the liquid path are collectively referred to as a nozzle.

  Further, the recording head 3 mounted on the carriage 2 is supplied with ink from ink tanks containing inks containing different color materials. In the present embodiment, the ink jet recording apparatus 1 is provided with an ink tank that stores ink containing cyan, magenta, yellow, and black color materials. In addition, a processing liquid tank is provided that contains a processing liquid that solidifies the ink by reacting with each ink and agglomerates the color material components contained in the ink. Each ink tank provided in the main body is connected to an ink supply port of the corresponding recording head 3 by a tube (not shown) to supply ink to each recording head.

  Reference numeral 7 shown in FIG. 1 denotes a recovery processing device as a recovery mechanism for maintaining the ink discharge performance from each discharge port 20 of the recording head 3 in a good state. The recovery processing device 7 is held and fixed at a predetermined position of the recording apparatus main body 1. The recovery processing device 7 includes suction recovery mechanisms 7A and 7B, a lifting mechanism (not shown) that lifts and lowers the suction recovery mechanisms, and an ink receiving box 8. In addition, the recovery processing device 7 includes a wiping recovery device 9 as a wiping mechanism that performs wiping. The recovery processing device 7 suppresses the increase in the viscosity of the ink and the processing liquid stored in the recording head 3 or removes the ink and the processing liquid adhering to the recording head 3 in order to remove the ink and the processing liquid. 3 is configured to perform a recovery process.

  The suction recovery mechanisms 7A and 7B perform a suction recovery process that is a form of the recovery process. Here, the suction recovery process is a process for replacing the ink in the nozzle with ink in a state suitable for ejection by forcibly sucking ink from the plurality of ejection ports 20 formed in the recording head 3. Thereby, the viscosity increase of the ink stored in the recording head 3 is suppressed. Specifically, the suction recovery mechanisms 7A and 7B cover the discharge port forming surface 21 (see FIG. 2) with a cap. At the same time, a negative pressure is generated in the cap by a pump (not shown) communicating with the cap, and a part of the ink stored in the recording head 3 is forcibly sucked from the discharge port 20 by the negative pressure. And collect. Each of the suction recovery mechanisms 7A and 7B performs a suction recovery process for each of the three nozzle row groups.

  A wiping recovery device (wiping recovery means) 9 as a wiping mechanism is provided at a position that can be opposed to an end position (for example, a home position of the recording head) of the moving path of the recording head 3 in the vertical direction. The wiping recovery mechanism 9 includes a wiping mechanism (wiping means) that wipes the ejection port forming surface 21 of the recording head using a wiping member (blade) 10, and a drive unit of the blade 10. The wiping recovery device 9 wipes the surface of the recording head 3 on which the ink ejection port 20c and the processing liquid ejection port 20d are formed with the blade 10 in order to remove the ink and the processing liquid adhering to the recording head 3. . Further, the recovery processing device 7 may have a preliminary ejection mechanism that performs ejection that is not related to recording of the stored ink in order to suppress the increase in the viscosity of the ink stored in the recording head. As the preliminary ejection mechanism, when the recording head ejects ink droplets that are not involved in recording for preliminary ejection, a receiving means for receiving the ink droplets may be provided. Thus, in the present embodiment, the recovery processing device 7 has at least one function of the suction recovery mechanisms 7A and 7B, the preliminary discharge mechanism, and the wiping recovery device 9. The recovery processing performed by the recovery processing device 7 is at least one of suction recovery processing performed by the suction recovery mechanisms 7A and 7B, preliminary discharge performed by the preliminary discharge mechanism, and wiping performed by the wiping recovery device 9. is there.

  FIG. 3 is a block diagram showing a configuration of a control system (control means) mounted on the recording apparatus main body 1 of the ink jet recording apparatus according to this embodiment. In FIG. 3, reference numeral 100 denotes a main control unit. The main control unit 100 includes a CPU 101, a ROM 102, a RAM 103, an input / output port 104, and the like. The CPU 101 executes processing operations such as calculation, control, discrimination, and setting. The ROM 102 stores a control program to be executed by the CPU 101 and the like. The RAM 103 is used as a buffer for storing binary print data representing ink ejection / non-ejection and a work area for processing by the CPU 101.

  The input / output port 104 is connected to drive circuits 105, 106, 107, and 109 such as a transport motor (LF motor) 112, a carriage motor (CR motor) 113, a recording head 3, and a recovery processing device 7 in the transport unit. ing. Further, other sensors are connected to the input / output port 104. Examples of sensors include a head temperature sensor (head temperature detecting means) 114 that detects the temperature of the recording head, a home position sensor 110 that is fixed to the carriage 2, and a temperature and humidity sensor that detects the temperature and humidity that are the usage environment of the main body 1. 115 etc. The main control unit 100 is connected to a host computer 116 via an interface circuit 111.

  Reference numeral 117 denotes a recovery processing counter that counts the amount of ink when the recovery processing device 7 forcibly discharges ink from the recording head 3. Reference numeral 118 denotes a preliminary ejection counter that counts preliminary ejection performed during recording before the start of recording or at the end of recording. Reference numeral 119 denotes a borderless ink counter that counts ink recorded outside the recording medium area when performing borderless recording, and reference numeral 120 denotes an ejection dot counter that counts ink ejected during recording. .

  Next, a recording operation and a recovery processing method executed by the ink jet recording apparatus having the above configuration will be described.

  First, the outline of the recording operation will be described. When recording data is received from the host computer 116 via the interface, the recording data is developed in a buffer of the RAM 103. When a recording operation is instructed, a transport unit (not shown) operates to transport the recording medium to a position facing the recording head 3. Here, the carriage 2 moves along the guide shaft 4 in the main scanning direction (X direction). As the carriage 2 moves, ink droplets are ejected from the recording head 3 and an image for one band is recorded on the recording medium. Thereafter, the recording unit conveys the recording medium by one band in the Y direction (sub-scanning direction) orthogonal to the carriage 2. By repeating the above operation, a predetermined image is formed on the recording medium.

  The position of the carriage 2 is detected by counting the pulse signal output from the encoder sensor 110 as the carriage 2 moves by the main control unit 100. That is, the encoder sensor 110 outputs a pulse signal to the main control unit 100 by detecting the detection units formed at regular intervals on the encoder film 6 (see FIG. 1) arranged along the main scanning direction. The main controller 100 detects the position of the carriage 2 by counting the pulse signals. The carriage 2 is moved to the home position and other positions based on a signal from the encoder sensor 110.

  When an instruction to perform the recovery process is issued at regular intervals, the recording apparatus performs the recovery process accordingly. In the present embodiment, the dot counter counts the number of ink ejected by the recording head, and the recovery process is performed when a certain count number is reached. At this time, as will be described later, the number of ink ejections counted by the dot counter is multiplied by a coefficient in accordance with the recording state. The frequency with which the recovery process is performed is adjusted by adjusting this coefficient.

  Hereinafter, the frequency with which the recovery process according to the present embodiment is performed will be described. In the recording apparatus of the present embodiment, recording is performed by ejecting ink along with ejection of processing liquid (first recording mode) for performing recording and ejecting ink without ejecting processing liquid. Has a recording mode (second recording mode). Hereinafter, the frequency at which the recovery process is performed according to the recording mode for determining whether or not the processing liquid is discharged and the recording duty when recording is performed will be described.

  First, a case where high duty recording is performed will be described. FIG. 4 is a schematic cross-sectional view showing an air flow state on the recording medium 12 when high duty recording is performed by the recording apparatus of the present embodiment.

  When high duty recording is performed in which the ratio of ink per unit area in a recorded image is large, generally the number of ejection ports used simultaneously tends to be large. Accordingly, since the number of ink droplets ejected simultaneously increases, the amount of ink mist generated thereby tends to increase. Further, since the amount of ink droplets ejected at the same time is large, the air flow generated by ink ejection is also increased. This airflow is a downward flow from the recording head 3 toward the recording medium when it is generated by ink ejection. When this airflow reaches the recording medium, an upward airflow is reflected from the recording medium toward the recording head 3. When the air flow 15 is increased by performing high duty recording, the ink mist is swung up by the upward air flow 15 and the amount of ink mist adhering to the surface portion 11 of the recording head 3 tends to further increase.

  A case (second recording mode) in which recording is performed without discharging processing liquid during high duty recording will be described. When such high duty recording is performed without discharging the processing liquid, only ink containing a color material is discharged with high duty. At this time, the generated ink mist may adhere to the surface portion 11 of the recording head 3, and this may increase the viscosity to generate a thickened material on the surface portion of the recording head 3. However, the thickened material generated on the surface portion 11 of the recording head 3 at this time is less thickened on the surface portion 11 than when the processing liquid is discharged. In this case, it is required that the recovery process be performed at an appropriate timing. As the recovery processing, suction recovery processing, preliminary discharge, wiping, or the like is performed.

  On the other hand, when the recording mode (first recording mode) in which the recording is performed with the discharge of the processing liquid is selected, the recording is performed with the discharging of the processing liquid while the high duty recording is performed. A relatively large amount of ink and processing liquid are discharged in parallel. At this time, a part of the processing liquid and ink becomes ink mist and floats between the recording head 3 and the recording medium. At this time, the discharge amount of the ink and the processing liquid is relatively high because high duty recording is performed. In addition, when high duty recording is performed as described above, the upward air flow from the recording medium toward the recording head 3 tends to be relatively large. The air current 15 is raised. At this time, the ink mist of the treatment liquid and the ink may be mixed and come into contact with each other in the process of floating and flying up by the airflow. When the treatment liquid contains a component that solidifies ink, the ink may thicken and solidify on the surface portion 11 of the recording head 3 due to the contact between the treatment liquid and the ink. As described above, the product 14 generated by mixing the ink and the treatment liquid may adhere to the surface portion 11 of the recording head 3 and solidify. The amount of this product is relatively large when recording with discharge of the treatment liquid is performed.

  In addition, the product 14 generated on the surface portion 11 of the recording head 3 has a larger amount of ink and processing liquid than the thickened material formed only by ink attached to the surface portion 11 when ink is ejected without the processing liquid. It adheres more strongly by reacting. Therefore, when recording is performed by ejecting ink droplets with the ejection of the treatment liquid, the recovery process frequency is increased, and the product 14 attached to the periphery of the ejection openings in the surface portion of the recording head 3 is frequently removed. Is required. If the frequency of the recovery process performed to remove the product 14 is insufficient and the timing for performing the recovery process is delayed, the product 14 may block the ejection port or affect the ink droplet landing accuracy. I will give it. For this reason, during recording, there is a possibility of causing non-ejection in which ink droplets are not ejected from the ejection port and ejection deviation in which the ink droplets deviate from a desired recording position. As described above, it is preferable to make the frequency of the recovery process relatively high under this recording condition.

  Next, a case where low duty recording with a small proportion of ink per unit area in a recorded image is performed will be described.

  FIG. 5 is a schematic cross-sectional view showing the state of airflow on the recording medium 12 when low-duty recording is performed by the recording apparatus of the present embodiment. When low duty recording is performed, since the number of ejection ports that eject ink simultaneously is small, the amount of ink mist generated is small. Furthermore, the air flow 15 generated when ink is ejected for recording is relatively small. For this reason, the amount of ink mist adhering to the surface portion 11 of the recording head 3 is relatively smaller than when high duty recording is performed.

  When low duty recording is performed, when recording is performed by selecting a recording mode that does not involve the discharge of the processing liquid, only ink containing a color material is ejected with a low duty. For this reason, the amount of ink that becomes ink mist out of the ink ejected for recording is small. Therefore, the amount of ink mist generated between the recording head and the recording medium is small, and the amount of ink mist adhering to the surface portion 11 of the recording head 3 is relatively small. Since the amount of generated ink mist is small, it is possible to remove the ink adhering to the surface portion 11 of the recording head 3 by a recovery process with a low frequency.

  On the other hand, when a recording mode in which recording is performed with the discharge of the treatment liquid is selected, the discharge of the treatment liquid and the discharge of the ink containing the color material are performed in parallel. Therefore, a part of the processing liquid and ink may become ink mist and float between the recording head 3 and the recording medium, and these may be mixed and contact each other. As a result, a product 14 generated by contact between the ink and the treatment liquid may be generated on the surface portion 11 of the recording head 3. Therefore, even when ink is ejected for low duty recording, if the processing liquid is ejected together with the ink when recording is performed, the processing liquid is dispensed in the same manner as when ejecting at a high duty. It is preferable to increase the frequency at which the recovery process is performed as compared with the case where the ejection is not performed.

  However, when low duty recording is performed, the amount of ink mist generated is smaller than when high duty recording is performed, and the amount of upward airflow from the recording medium toward the recording head 3 is also small. Therefore, when recording is performed with low duty recording, the frequency of the recovery process may be less than when recording with high duty. By reducing the frequency of the recovery process, recording can be performed efficiently and the throughput in recording can be improved.

  Note that the recording apparatus 1 of the present embodiment includes a duty detection unit that detects a duty in a recorded image by ink ejected from the ejection port. In the present embodiment, the duty in the recorded image is detected in advance by recording data sent from the host computer via the interface. The duty in the recorded image may be detected from the recorded image. At this time, the CPU 101 or the like functions as duty detection means for detecting the duty in the recorded image. Using the detected duty, a coefficient to be multiplied by the counted number of ink ejections when the dot count number is calculated by the ejection dot counter 120 is determined.

  Next, adjustment of the frequency with which the recovery process executed by this embodiment is performed will be described. Here, in the recovery process, a suction recovery process is performed in which the ejection port of the recording head is covered with a cap, and ink in the recording head is sucked through the cap in this state. A flow of a process in which the recovery process is performed at this time will be described with reference to a flowchart of FIG. In the flowchart of FIG. 6, when a recording mode is selected in 201 and a recording medium suitable for the case of using a processing liquid such as plain paper or coated paper is selected, a recording operation involving the discharge of the processing liquid is performed, The processing liquid is set to the ON state. In addition, when a recording medium suitable for not using the processing liquid, such as glossy paper, is selected, a recording mode in which recording is performed without discharging the processing liquid is selected, and the processing liquid is set to the OFF state. The In the present embodiment, depending on the type of the selected recording medium, either the recording operation with the discharge of the processing liquid or the recording operation without the discharge of the processing liquid is selected. It is not limited to this. Either a recording mode with processing liquid discharge or a recording mode without processing liquid discharge may be selected by a user instruction, or any recording mode may be selected by another method. It is also good. Then, the number of ejections of ink ejected from the ejection ports is counted. At this time, not only the ink but also the number of ejections of the treatment liquid may be counted.

  In the flowchart, when the processing liquid is in the ON state, the discharge dot counter 120 serving as a dot count unit is multiplied by a coefficient corresponding to the recording duty of the ink containing the processing liquid and the color material in 202 and is used as a dot count unit. Is calculated by If the processing liquid is in the OFF state, the ejection dot counter 120 calculates the coefficient corresponding to the recording duty of the ink containing the color material in 203 and multiplies the ejection number of ink. In this manner, the ejection dot counter 120 calculates the dot count number by multiplying the counted number of ink ejections by the coefficient corresponding to the recording condition. The ejection dot counter 120 multiplies the number of ejections by a larger coefficient when recording is performed in a recording mode in which recording is performed with ejection of the processing liquid than when recording is performed in recording mode without ejection of the processing liquid. The dot count number is calculated.

  When the recording data for one line is recorded in 204, the number of ejections ejected in accordance with the recording data is counted in 205 by the dot counter process. In this embodiment, the number of dot counters is integrated by multiplying the total number of discharges by combining the number of discharges by the treatment liquid and the number of discharges by the ink containing the color material by the coefficient set in 202 or 203. At this time, if the inkjet recording apparatus counts the number of ejections for ink and the number of ejections for the processing liquid, the coefficient multiplied by the ejection dot counter 120 is the coefficient for the ink and the coefficient for the processing liquid. May be set separately. If the number of dot counters accumulated in 206 exceeds the threshold value, recovery processing is performed in 207. In this way, the timing at which the recovery process is performed is controlled so that the recovery process is performed when the dot count number calculated by the ejection dot counter 120 exceeds a preset threshold value.

  The frequency of the recovery process when the recording is performed with the discharge of the processing liquid is higher than the frequency of the recovery process when the recording is performed without the discharge of the processing liquid. The timing to be performed is controlled. In addition, when the duty of the recorded image is large, the timing at which the recovery process is performed is controlled so that the frequency of the recovery process is higher than when the duty is small. At this time, for example, the CPU 101, the ROM 102, the RAM 103, and the like function as a recovery process control unit that controls the timing at which the recovery process is performed.

  Then, at 208, the dot counter number is reset. If the next scan data is present at 209, the recording data for one line is continuously recorded at 204, and if there is no next scan data, the recording is terminated at 210. On the other hand, if the number of dot counters integrated in 206 does not exceed the threshold value and there is next scan data in 209, the recording data for one line is continuously recorded in 204. If there is no next scan data at 209, the recording ends at 210.

  The recovery process is not limited to the suction recovery process, and the same effect can be obtained by preliminary ejection and wiping, and the suction recovery process, preliminary ejection, and wiping can be executed in combination.

  FIG. 7 shows a table showing whether or not the treatment liquid is ejected during printing by the ink jet printing apparatus of the present embodiment and the coefficient that changes according to the printing duty. The coefficient multiplied by the number of ejections is multiplied by the ejection dot counter 120 for the number of ink ejections by printing. Further, the number of discharges during preliminary discharge is multiplied by the preliminary discharge counter 118. The table also shows the ejection state of the recording head after recording is performed on 1000 recording media of A0 paper when recording is performed using the coefficient. In the present embodiment, when plain paper is selected as the recording medium, recording is performed with the discharge of the processing liquid. Therefore, in this case, it is possible to increase the recovery processing frequency by setting the dot counter coefficient multiplied by the number of ejections to be larger than the dot counter coefficient when glossy paper that does not eject the processing liquid is selected. Regardless of whether or not the processing liquid is ejected, the recovery counter frequency is increased by increasing the dot counter coefficient of the ink containing the processing liquid and the color material as the recording duty increases. Further, the recovery processing frequency is increased by making the dot counter coefficient of the processing liquid larger than the dot counter coefficient of the ink containing the color material when the processing liquid is discharged. As a result of observing the discharge state after recording 1000 sheets of images used from low duty to high duty for each A0 size of plain paper and glossy paper under the conditions of this embodiment, there is no non-ejection or ejection deviation There was no occurrence of image defects in the proper discharge state.

  On the other hand, FIG. 8 shows a table showing a coefficient to be multiplied by the number of ink ejections, which varies depending on whether or not the treatment liquid is ejected and the recording duty during the recording in the comparative example. In the comparative example, the dot counter coefficient is set to 1 at the time of printing regardless of whether the processing liquid is discharged and the printing duty. As a result of recording 1000 images similar to FIG. 7 and observing the ejection state, the product was deposited and solidified on the surface portion of the recording head, and non-ejection and ejection deviation occurred, resulting in an image defect. .

  By performing recording by the ink jet recording apparatus of the present embodiment, the recovery process can be performed at an appropriate timing even when recording is performed by ejecting ink with the ejection of the treatment liquid. Accordingly, it is possible to suppress the ink ejection from being affected by the product generated when the ink and the treatment liquid come into contact with the recording head. Therefore, the quality of the image obtained by recording is kept high. In addition, the durability of the recording apparatus is suppressed from being affected by the attached product, and the reliability of the recording apparatus can be improved. Further, when the treatment liquid is not discharged, the frequency of the recovery process is controlled to be low, so that the recording efficiency can be improved and the recording throughput can be improved.

  In the present specification, “recording” is used not only for forming significant information such as characters and graphics but also for any case. It also represents the case where images, patterns, patterns, etc. are widely formed on a recording medium, or the recording medium is processed, regardless of whether it is manifested so that it can be perceived by human eyes. And

  The “recording device” includes a device having a printing function such as a printer, a printer multifunction device, a copying machine, and a facsimile device, and a manufacturing device that manufactures an article using an ink jet technique.

  “Recording medium” means not only paper used in general recording apparatuses but also a wide range of materials that can accept ink, such as cloth, plastic film, metal plate, glass, ceramics, wood, leather, etc. Shall.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 3 Recording head 20 Discharge port 20c Discharge port for ink 20d Discharge port for treatment liquid

Claims (4)

A recording head having an ink ejection port for ejecting ink containing a coloring material, and a treatment liquid ejection port for ejecting a treatment liquid containing a component that solidifies by contact with the ink;
A recovery process is performed on the recording head for at least one of suppressing the increase in the viscosity of the ink and the processing liquid stored in the recording head or removing the ink and the processing liquid adhering to the recording head. A recovery mechanism,
Recording is performed by ejecting ink from the ink ejection port onto the recording medium, and ejecting the treatment liquid from the processing liquid ejection port and bringing it into contact with the ink ejected from the ink ejection port. In an ink jet recording apparatus capable of solidifying ink landed on
A first recording mode for performing recording by ejecting ink from the ink ejection port with ejection of the processing liquid from the processing liquid ejection port;
A second recording mode for performing recording by discharging ink from the ink discharge port without discharging the processing liquid from the processing liquid discharge port;
The frequency of the recovery process when recording is performed in the first recording mode is higher than the frequency of the recovery process when recording is performed in the second recording mode. An inkjet recording apparatus, comprising: recovery processing control means for controlling the timing to be performed. The recovery mechanism includes a suction recovery mechanism that sucks and collects a part of the stored ink in order to suppress increase in viscosity of the ink stored in the recording head, and an increase in the amount of ink stored in the recording head. A preliminary discharge mechanism that discharges ink not stored in order to suppress viscosity, and an ink discharge port and a processing liquid discharge in the recording head to remove ink and processing liquid adhering to the recording head. At least one of wiping mechanisms for wiping the surface on which the outlet is formed;
The recovery process is at least one of a suction recovery process performed by the suction recovery mechanism, a preliminary discharge performed by the preliminary discharge mechanism, and a wiping performed by the wiping mechanism. 2. An ink jet recording apparatus according to 1. The inkjet recording apparatus includes a dot count unit that counts the number of ejections ejected from the ink ejection port and calculates a dot count number by multiplying the counted ejection number by a coefficient according to a recording condition. And
The recovery process control means controls the timing at which the recovery process is performed so that the recovery process is performed when the dot count number calculated by the dot count means exceeds a preset threshold value,
The dot count means calculates the dot count by multiplying the number of ejections by a larger coefficient when performing printing in the first recording mode than when performing printing in the second recording mode. The ink jet recording apparatus according to claim 1 or 2. Having a duty detection means for detecting a duty in a recorded image by ink ejected from the ink ejection port;
The recovery process control means performs the recovery process so that when the duty detected by the duty detection means is large, the frequency of the recovery process is higher than when the duty detected by the duty detection means is small. The ink jet recording apparatus according to claim 1, wherein the timing at which the ink is discharged is controlled.

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