JP2019005910A - Inkjet recording device - Google Patents

Abstract

To provide a technique that can reduce ink amounts to be used for suppressing ink from depositing while favorably suppressing the ink from depositing in an ink receiving part.SOLUTION: The inkjet recording device comprises: a recording head that discharges first ink which deposits and second ink which suppresses the first ink from depositing; an ink receiving part that receives ink discharged from the recording head; and control means that performs discharging control by which the first ink and the second ink are discharged to the ink receiving part after and before recording operation. In the inkjet recording device, the control means performs the discharging control after the recording operation so that ink amounts which are discharged when discharge amounts of the first ink in the recording operation are more than a predetermined amount are smaller than ink amounts which are discharged when the discharge mounts are less than the predetermined amount.SELECTED DRAWING: Figure 11

Description

  The present invention relates to an ink jet recording apparatus.

  In Patent Document 1, ink is absorbed by ejecting ink (deposition suppression ink) that suppresses the accumulation of ink after the recording operation is completed to an ink absorber from which ink that is easily deposited (deposited ink) is ejected. Techniques for suppressing ink accumulation in the body are disclosed.

JP 2012-51198 A

  The amount of ink ejected in order to suppress ink accumulation in the ink absorber (ink receiving portion) needs to be set in consideration of water evaporation of ink from the recording head. In particular, more water evaporates from the ink nozzles that are not used much in the recording operation during the recording operation. When the water in the ink evaporates, the ejection effect for suppressing ink accumulation is reduced. That is, even when ejection for suppressing ink accumulation is performed after the recording operation is completed in a state where moisture evaporation in the ink has progressed, ink accumulation may not be sufficiently suppressed. Therefore, it may be possible to set a large amount of ink to be ejected after the end of the recording operation in consideration of the water evaporation of the ink, but there is a problem that the amount of ink consumption increases.

  The present invention has been made in view of the above-described problems, and it is possible to reduce the amount of ink used to suppress ink accumulation while suitably suppressing ink accumulation on the ink receiving portion. The purpose is to provide technology.

  In order to solve the above problems, an ink jet recording apparatus according to the present invention records an image on a recording medium by ejecting a first ink in which ink deposition occurs and a second ink for suppressing the ink deposition. A recording head that performs a recording operation, an ink receiving portion that receives ink discharged from the recording head, and a predetermined amount of ink that is discharged to the ink receiving portion before performing the recording operation when a recording command is issued The first ink control and the second ink to the ink receiving portion in order to suppress the accumulation of the ink discharged in the first discharge control after performing the recording operation. An ink jet recording apparatus comprising: a control unit that performs a second discharge control for discharging the ink in the second discharge control. The amount of ink discharged when the discharge amount of the first ink is larger than a predetermined amount is made smaller than the amount of ink discharged when the discharge amount of the first ink is smaller than the predetermined amount. .

  ADVANTAGE OF THE INVENTION According to this invention, the technique which can reduce the ink consumption used in order to suppress the accumulation of ink can be provided, suppressing the accumulation of the ink to an ink receiving part suitably.

1 is a perspective view showing an ink jet recording apparatus according to a first embodiment. It is a perspective view which shows the structure of the recording part which concerns on 1st Embodiment. FIG. 3 is a schematic cross-sectional view showing the periphery of a recording unit according to the first embodiment. It is a block diagram which shows the structure of the control part which concerns on 1st Embodiment. It is a schematic diagram of the recovery unit according to the first embodiment. It is a flowchart for demonstrating the discharge control to a cap. It is a figure explaining the relationship between the ejection number to a cap, and the accumulation of ink. It is a figure for demonstrating the image recorded in 1st Embodiment. FIG. 9 is a table for explaining a relationship between an image and ink accumulation in FIG. 8. FIG. It is a table | surface for demonstrating the relationship between the image in FIG. 8, and the preliminary discharge amount after recording. It is a flowchart which shows the control which concerns on 1st Embodiment. It is a flowchart which shows the control which concerns on 2nd Embodiment. It is a schematic diagram which shows the relationship between the recording medium at the time of performing a borderless recording operation in 3rd Embodiment, and a platen absorber. It is a schematic diagram for demonstrating the count area | region of the accumulation ink at the time of performing a borderless recording operation in 3rd Embodiment. It is a flowchart which shows the deposition suppression control in 3rd Embodiment. It is a flowchart for demonstrating the control which concerns on 3rd Embodiment.

(First embodiment)
Hereinafter, an ink jet recording apparatus according to a first embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing an ink jet recording apparatus (recording apparatus) according to the present embodiment. The recording apparatus 1 according to the present embodiment discharges a recording unit that feeds a recording medium, a conveying unit that conveys a recording medium (sheet), a recording unit that records an image on the recording medium, and a recording medium on which an image is recorded And a recovery unit that recovers the recording performance of the recording unit.

  The feeding unit includes a feeding tray on which a plurality of recording media are stacked, and a feeding roller that feeds recording media stacked on the feeding tray one by one into the recording apparatus.

  The conveyance unit includes a conveyance roller 400 that conveys the recording medium fed from the feeding unit, and a pinch roller 401 that is disposed at a position facing the conveyance roller and sandwiches the recording medium together with the conveyance roller.

  The recording unit includes a recording head 101 having an ejection port surface (nozzle surface) provided with ejection ports (nozzles) for ejecting ink, and a carriage 100 on which the recording head 101 is detachably mounted. The carriage 100 is configured to be capable of reciprocating in the X direction (carriage moving direction) along the guide shaft 113 via a timing belt 112 attached to the chassis 111 by driving of a carriage motor 110. The recording medium is transported in the Y direction (recording medium transport direction) intersecting the X direction. The recording head 101 records an image by ejecting ink onto a recording medium stopped at a position facing the recording head 101 while the carriage 100 is reciprocating. A platen 300 that supports the recording medium from below is provided at a position facing the recording head 101 so as to keep the distance between the surface (first surface) of the recording medium and the ejection port surface of the recording head 101 constant. Yes. The platen 300 is provided with a platen absorber 301 that absorbs ink ejected outside the recording medium.

  The discharge unit includes a discharge roller 402 that discharges the recording medium on which the image is recorded to the outside of the recording apparatus, and a spur roller 403 that presses the recording medium at a position facing the discharge roller.

  The recovery unit includes a cap 500 that covers the ejection port surface 102 of the recording head 101 outside the recording area in the movement direction of the carriage 100. The recovery unit sucks ink from the recording head 101 by driving the suction pump 503 connected to the cap 500 via the tube 502 in a state where the cap 500 covers the ejection port surface 102 of the recording head 101. Has a suction mechanism. The recovery unit also includes a wiper 506 that wipes the ejection port surface of the recording head. Details of the recovery unit will be described later.

  Next, the recording unit of the recording apparatus according to the present embodiment will be described in detail. FIG. 2 is a perspective view illustrating the configuration of the recording unit according to the present embodiment. A recording head 101 is detachably mounted on the carriage 100. Further, nine types of ink tanks (ink cartridges) 103 are detachably attached to the recording head 101. The recording apparatus according to the present embodiment records an image with nine types of ink, and nine independent ink tanks 103 are attached to the recording head 101. In the present embodiment, these nine types of ink tanks contain (store) nine types of pigment inks of cyan, magenta, yellow, black, red, light cyan, light magenta, gray, and clear ink, respectively.

  Next, the conveyance operation and the recording operation of the recording apparatus according to the present embodiment will be described in detail. FIG. 3 is a schematic cross-sectional view of the periphery of the recording unit according to the present embodiment when viewed from the X direction of FIG. The recording medium P fed from the feeding unit is nipped and conveyed by the conveying roller 400 and the chiller 401 provided on the upstream side of the recording head 101 in the Y direction. The recording medium P is also sandwiched between the discharge roller 402 and the roller 403 provided on the downstream side of the recording head 101 in the Y direction. The recording medium P is conveyed while the surface is kept flat by being sandwiched between the conveying roller 400 and the pinch roller 401, the discharge roller 402 and the spur roller 403. The transported recording medium P is supported by the platen 300 from below.

  The recording medium P to be transported is discharged for one band (1) by ejecting ink droplets from the ejection ports of the recording head 101 mounted on the carriage 100 moving in the X direction while the transport is stopped. (Line feed) image is recorded. When an image for one band is recorded, the recording medium P is transported by a predetermined amount in the Y direction by driving a transport roller 400 by a predetermined amount by a transport motor (not shown). The discharge of ink droplets by the recording head 101 while the carriage 100 is moving and the conveyance of the recording medium P by a predetermined amount (intermittent conveyance) by the conveyance roller 400 are alternately repeated, whereby the entire recording medium P is obtained. An image for one page is recorded in the.

  Next, the configuration of the control unit of the recording apparatus according to the present embodiment will be described in detail. FIG. 4 is a block diagram illustrating a configuration of the control unit according to the present embodiment. In FIG. 4, a CPU 1000 executes control and data processing of each part of the apparatus via a main bus line 1013. The CPU 1000 executes data processing, control of print head drive and carriage drive, print operation, maintenance operation including preliminary discharge operation, and the like according to a program stored in the ROM 1001.

  The CPU 1000 can perform communication processing with the host device via the interface 1004. The RAM 1002 is used as a work area for data processing by the CPU 1000. The RAM 1002 temporarily stores recording data used for the recording operation, parameters related to the recovery operation and supply operation of the recording apparatus, and the like. The image input unit 1003 temporarily holds an image input from the host device via the interface 1004.

  Further, the CPU 1000 calculates the amount of waste ink stored in the waste ink storage unit (waste ink pack) 504 that stores the waste ink by counting the amount of ink consumed by the suction operation by the recovery unit. The CPU 1000 can notify the host device or the like via the interface 1004 of a warning that the waste ink container 504 is full. The nonvolatile memory 1005 stores and stores information related to the amount of ink stored in the waste ink storage unit 504, the amount of ink ejected to the platen absorber 301, and the like. The nonvolatile memory 1005 can hold information even when the power of the recording apparatus is turned off.

  The recovery system control circuit 1008 controls the drive of the recovery system motor 1009 according to the recovery processing program stored in the RAM 1002. The recovery system control circuit 1008 controls the recovery system motor 1009 to drive the recovery operation such as the raising / lowering operation (capping operation) of the cap 500, the wiping operation (wiping operation) of the wiper 506, and the suction operation of the suction pump 503. (Cleaning operation) is controlled.

  The head drive control circuit 1010 controls the ink ejection drive of the recording head 101 and causes the recording head 101 to eject ink for preliminary ejection and recording operation.

  The carriage drive control circuit 1011 controls the reciprocation of the carriage 100 according to the recording data processed by the image signal processing unit 1006, and controls the movement of the carriage 100 to the recovery unit when performing the recovery operation.

  The conveyance control circuit 1012 controls driving of the conveyance motor in accordance with a program stored in the RAM 1002. After the recording of the image data for one band by the recording head 101 is completed, the conveyance control circuit 1012 performs control for conveying a predetermined amount of the recording medium according to the recording data in order to record the image data for the next band.

  Next, the configuration of the recovery unit (recovery unit) of the recording apparatus according to the present embodiment will be described in detail. FIG. 5 is a schematic diagram of a recovery unit according to the present embodiment. As described above, the recovery unit has the cap 500 that covers the ejection port surface 102 of the recording head 101 when performing various recovery operations. In the cap 500, a cap absorber (ink absorber, ink receiving portion) 501 is provided at a position facing the discharge port surface 102 of the recording head. A minute space is provided between the cap absorber 501 and the ejection port surface 102 of the recording head. The cap 500 communicates with the suction pump 503 via the tube 502 at the lower side.

  When the suction pump 503 is driven, a negative pressure is generated in the space between the recording head 101 and the cap 500, and ink is sucked from the ejection port of the recording head 101. The sucked ink is discharged to the waste ink storage portion 504 connected via the tube 502. As described above, by sucking ink from the ejection port of the recording head 101, it is possible to prevent ink sticking or bubbles from being mixed in the recording head.

  Further, if the state in which ink is not ejected from the recording head 101 continues for a certain period of time or more, the ink thickens due to moisture evaporation from the ejection port of the recording head 101, and there is a risk of ink ejection failure at the start of the recording operation. Therefore, for the purpose of preventing ejection failure at the start of the recording operation, before performing the recording operation, the recording head is moved to a position facing the cap by the carriage, and preliminary ejection is performed to eject a specified amount of ink to the cap. Perform the action. This preliminary ejection operation is also referred to as pre-recording preliminary ejection and pre-recording cap preliminary ejection.

  This pre-recording preliminary ejection is desirably performed with a minimum ink consumption within a range in which ejection failure during a recording operation can be prevented. However, as described later, when a small amount of ink is ejected to the cap 500 and left for a certain period of time, the ink in the cap dries and thickens, and there is a risk of ink accumulation.

  Therefore, in order to prevent the ink from being deposited, after performing the recording operation, the recording head performs a preliminary ejection operation for ejecting a predetermined amount of ink to the cap. This preliminary ejection operation is also referred to as post-recording preliminary ejection, post-recording cap preliminary ejection, and post-control. By this preliminary discharge operation, the moisture ratio in the cap increases, and ink accumulation in the cap can be suppressed.

  In the present embodiment, among the nine types of pigment inks, dark inks such as magenta ink, cyan ink, yellow ink, black ink, and red ink have a high solid component ratio, and moisture in the ink evaporates. It is easily fixed and hardly absorbed by the ink absorber. Therefore, these inks are classified as “deposited ink” (first ink) that is easily deposited on the ink absorber. On the other hand, inks such as light cyan ink, light magenta ink, and clear ink have few solid components, are not easily fixed, and are easily absorbed by the ink absorber. Since these inks also have an action of promoting the absorption of the accumulated pigment ink, they are classified as “deposition suppression ink” (second ink) that suppresses the accumulation on the ink absorber.

  Here, the ink is classified into the accumulation ink and the accumulation suppression ink according to the amount of the solid component, but may be classified into the accumulation ink and the accumulation suppression ink according to the amount of the solvent or the humectant contained in the ink. When the ink contains a large amount of solvent or the like, the increase in the viscosity of the deposited ink can be suppressed, and the deposited ink can be easily absorbed by the ink absorber. Therefore, pigment inks that contain a large amount of solvent / humectant may be classified as deposition suppression inks. Further, the deposited ink may be classified as a pigment ink, and the accumulation suppressing ink may be classified as a dye ink.

  In the preliminary discharge after recording in the present embodiment, the deposition suppression ink is discharged to the cap 500 after the end of the recording operation in order to suppress the accumulation of ink discharged in the preliminary discharge before recording. At this time, the ink ejected in the preliminary ejection after recording is not limited to the deposition suppression ink, and the deposited ink may be ejected together. Even if the deposited ink is ejected together with the deposition inhibiting ink, the moisture ratio in the cap increases, so that there is an effect of suppressing the accumulation of ink in the cap.

  In addition, when the amount of ink that exceeds the cap capacity is discharged into the cap due to the preliminary discharge of the cap, the ink may overflow from the cap. Accordingly, the suction pump 503 is driven at a predetermined timing to execute a suction operation for sucking ink in the cap. This suction operation is also referred to as idle suction.

  FIG. 6 is a flowchart for explaining discharge control to the cap. First, in step S131, a recording command is received from the CPU 1000. If a recording command is received, it will progress to the following step S132 and will perform preliminary discharge before recording with respect to a cap. In this pre-recording preliminary ejection, 100 dots (100 shots) of each color nozzle are ejected onto the cap 500. Then, after performing the preliminary ejection before recording, the process proceeds to step S133, and the recording operation is started. When the recording operation is completed, the process proceeds to step S134, and a wiping operation for wiping the discharge port surface of the recording head 101 with the wiper 506 is performed to clean the recording head 101.

  In step S <b> 135, the recording head 101 is moved again to a position facing the cap 500 by the carriage 100 in order to suppress the ink ejected on the cap in the preliminary ejection before recording, and the preliminary ejection is performed on the cap 500. I do. In this preliminary discharge after recording, 2000 nozzles of each color are discharged onto the cap 500. In the preliminary discharge after recording, inks of all colors including the accumulation ink as well as the accumulation suppression ink can be discharged, so that the ink mixed in color by the wiping operation can be discharged out of the discharge port. After the preliminary discharge after recording, the process proceeds to step S136, and the suction pump 503 is driven to perform the empty suction for sucking and discharging the ink in the cap. After the idle suction is performed, this control ends.

  Next, the relationship between the post-recording preliminary ejection and the ink deposition investigated by the present inventors will be described. FIG. 7 is a view for explaining the relationship between the number of ejections to the cap and the accumulation of ink. Referring to FIG. 7, the relationship between the post-recording preliminary ejection amount (number of ejections and number of ejection dots) and the accumulation of ink in the cap when a predetermined recording image (recording pattern) is continuously recorded will be described. To do. In FIG. 7A, 1000 preliminary ejections were performed on the cap after the recording operation was completed. When ten images were recorded continuously in a low humidity environment (temperature 30 ° C., humidity 10%), after a predetermined time, the black ink that tends to deposit adhered and deposited in the cap. Further, when 20 images were recorded continuously, the ink deposition after a predetermined time further grew.

  In (B), 2000 preliminary discharges were performed on the cap after the recording operation was completed. Since the amount of ejected ink was larger than that in 1000 shots of (A), the inside of the cap was wet, and the ink was difficult to deposit. Therefore, ink accumulation was suppressed when 10 sheets were recorded. On the other hand, when 20 sheets were recorded in (B), ink accumulation occurred. In (B), although the ink deposition could be suppressed more than in the case of (A), since the deposited ink remains in the cap absorber, the evaporation of water proceeds and the ink deposition does not occur after a predetermined time. Will occur. Further, if the number of ejections is increased more than this, ink having an amount of ink larger than the cap volume is ejected to the cap, and the ink may overflow from the cap.

  Therefore, in (C), as a measure for suppressing ink accumulation and ink overflow, 2000 preliminary discharges are performed on the cap after the recording operation is completed, and then the suction pump is driven to remove the ink in the cap. An empty suction to suck was performed. By performing this empty suction immediately after the preliminary discharge of the cap, it was possible to prevent the ink from overflowing from the cap. Further, since the ink of the cap absorber can be discharged before the ink evaporates due to this empty suction, the ink deposition can be further suppressed than in the case of (B).

  According to the study by the present inventors, ink accumulation occurs when the ratio of the pigment / solid content in the ink increases due to evaporation of water, and the ink adheres to the ink absorber. In particular, when a predetermined ink is not used much in the recording operation, the water of the unused ink evaporates from the ejection port during the recording operation, and the ink is thickened. It has been found that if such ink is ejected and landed on the cap absorber in the preliminary ejection after recording, the effect of suppressing the accumulation of ink is reduced. On the other hand, regarding ink that is often used in the recording operation, fresh ink is supplied to the nozzle by use. It has been found that even when such ink is ejected and landed on the cap absorber in the preliminary ejection after recording, the effect of suppressing the accumulation of ink does not decrease.

  The present inventors conducted an experiment to investigate the relationship between the deposited ink and the non-ejection time in the recording operation using black ink as the deposited ink. In the experiment, the state of accumulation of black ink on the ink absorber when the recording operation was performed with three types of recorded images using black ink was confirmed. At this time, recording patterns as shown in FIGS. 8A, 8B, and 8C were used as the three types of recorded images. (A) is a recording pattern in which there is an image (an image of one line along the Y direction) only near the left end of the recording medium P. (B) is a recording pattern of a so-called solid image (600 dpi) having an image on the entire surface. In (C), the length of the image in the Y direction is half of (A) and (B), and the total driving amount (total discharge amount) is the same as (A) in the vicinity of the left end of the recording medium P. This is a recording pattern having such an image (a two-line image along the Y direction). (C) is half the recording time required for the recording operation (A).

  FIG. 9 is a table showing the state of ink accumulation in the cap absorber when 20 images of (A), (B), and (C) in FIG. 8 are continuously recorded. Here, in the preliminary discharge before recording, 100 nozzles of each color were discharged to the cap, and in the preliminary discharge after recording, discharge of 1000 nozzles of each color was performed. As a result, ink accumulation occurred in (A), and no ink accumulation occurred in (B) and (C).

  FIG. 10 shows a preliminary discharge after recording in order to suppress ink accumulation in the cap absorber when 20 images of (A), (B), and (C) in FIG. This is the result of examining the required number of ink ejections. As a result, in (A), in order to suppress ink accumulation, it is necessary to eject 2000 inks in the preliminary discharge after recording. In (B) and (C), in order to suppress ink accumulation, It has been found that it is sufficient to eject 1000 inks in the preliminary ejection after recording.

  With regard to (A), since black ink was not used much in the recording operation, the moisture of the ink evaporated from the recording head, the ink viscosity increased, and the effect of suppressing ink accumulation during preliminary ejection after recording was achieved. This is because of the decrease. On the other hand, with regard to (B), since a large amount of black ink was used in the recording operation, the moisture of the ink did not evaporate much from the recording head, the ink viscosity did not increase, and the effect of suppressing ink accumulation during preliminary ejection after recording was achieved. This is because the value did not decrease. Regarding (C), black ink is not used much in the recording operation, but the recording time required for the recording operation is short, so that the water content of the ink does not evaporate from the recording head so much and the viscosity of the ink does not increase. This is because the effect of suppressing the accumulation of ink during preliminary ejection after recording did not decrease.

  As described above, when the ink amount of the accumulated ink used in the recording operation is larger than the predetermined amount, or when the recording time is shorter than the predetermined time, the amount of ink discharged in the preliminary discharge after recording can be reduced. I understood that I could do it. Specifically, when the number D of black ink ejections in the recording operation is larger than a predetermined number of dots Dth (predetermined amount) (D> Dth), the number of ejections in preliminary ejection after recording is less than the normal number of 2000. Can be suppressed. Further, when the recording time T required for the recording operation is shorter than the predetermined time Tth (T <Tth), the number of ejections in the preliminary ejection after recording can be suppressed to 1000, which is smaller than the normal 2000.

  The present invention has been made on the basis of the above-described new knowledge. Hereinafter, characteristic control according to the present embodiment will be described with reference to the flowchart of FIG.

  First, in step S101, a recording command is received from the CPU 1000. If a recording command is received, it will progress to the following step S102 and will perform preliminary discharge before recording with respect to a cap. The number of inks ejected in the preliminary ejection before recording is 100 for each nozzle of each color. This is the amount of ink necessary to discharge ink thickened by evaporation of moisture from the discharge port so as not to cause an ejection failure in the recording operation and prevent image formation. Next, the process proceeds to step S103, and the measurement of the consumption amount and the recording time of the accumulated ink (black ink in the present embodiment) is started. In step S104, a recording operation for recording an image related to the recording command on the recording medium is started. When the recording operation is completed, in step S105, the measurement of the consumed amount of ink and the recording time is ended. In step S106, a wiping operation for wiping the ejection port surface of the recording head is performed for the purpose of removing ink and paper dust adhering to the ejection port surface of the recording head.

  Next, in step S107, it is determined whether or not the measured recording time is longer than a predetermined time Tth. If the recording time is longer than the predetermined time Tth, the process proceeds to step S108. In step S108, it is determined whether or not the measured amount of accumulated ink consumption is greater than a predetermined number of dots Dth. If the amount of accumulated ink consumed is less than the predetermined number of dots Dth, the process proceeds to step S109. At this time, the moisture of the deposited ink evaporates from the ejection port, and the viscosity of the ink progresses, and the effect of suppressing the ink accumulation due to the preliminary ejection after recording is reduced. Therefore, in step S109, as usual, pre-discharge after recording for each nozzle of 2000 for each color is performed, and the process proceeds to step S111. In the preliminary discharge after recording here, a sufficient discharge amount is set in consideration of the evaporated amount of the accumulated ink. Therefore, the preliminary discharge after recording can suppress the accumulation of ink in the cap absorber. . Further, in the preliminary discharge after recording here, the ink of each color including the accumulation ink as well as the accumulation suppression ink is ejected, so that the ink of each color mixed by performing the wiping operation can be discharged out of the ejection opening.

  On the other hand, if the recording time is shorter than the predetermined time Tth in step S107, or if the amount of accumulated ink consumed is larger than the predetermined number of dots Dth in step S108, the process proceeds to step S110. At this time, the moisture of the accumulated ink does not evaporate so much from the ejection port, and the viscosity of the ink does not increase so much, and the effect of suppressing the ink accumulation due to the preliminary ejection after recording does not deteriorate. Therefore, in step S110, the number of inks ejected in the preliminary ejection after recording can be reduced, and the preliminary ejection after recording is performed for 1000 nozzles of each color, and the process proceeds to step S111. Similarly, by discharging the deposition-inhibiting ink and the deposited ink in the preliminary ejection after recording, it is possible to eject the ink of each color mixed by the wiping operation from the ejection port.

  Next, in step S111, the suction pump is driven to perform idle suction. Thereby, it is possible to prevent the ink from overflowing from the cap. After performing this idle suction, this control is finished.

  In the present embodiment, in the preliminary discharge after recording, it is set to discharge 2000 inks in the normal preliminary discharge after recording and 1000 inks in the preliminary discharge after recording with the discharge amount reduced, but the present invention is limited to this. Is not to be done. For example, it may be changed according to the recording time, the amount of accumulated ink consumed during the recording operation, and the like.

  Further, the easiness of ink evaporation varies depending on the environmental temperature and the environmental humidity. In an environment of high temperature and low humidity, the ink tends to thicken as the water evaporates. On the other hand, in a low-temperature and high-humidity environment, ink does not evaporate and does not thicken easily. Therefore, in the preliminary ejection after recording, the preliminary ejection amount may be reduced as the temperature and humidity become lower. That is, in the preliminary ejection after recording, the amount of ink ejected when the environmental temperature is lower than the predetermined temperature may be smaller than the amount of ink ejected when the environmental temperature is higher than the predetermined temperature. In the preliminary ejection after recording, the amount of ink ejected when the environmental humidity is higher than the predetermined humidity may be less than the amount of ink ejected when the environmental humidity is lower than the predetermined humidity.

  As described above, according to the present embodiment, when the amount of accumulated ink used in the recording operation is larger than a predetermined amount, or when the recording time is shorter than the predetermined time, the amount of ink ejected in the preliminary ejection after recording. Reduce. Accordingly, it is possible to reduce the amount of ink consumed for suppressing ink accumulation while suitably suppressing ink accumulation on the cap.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to the drawings. Note that the description of the same configuration as in the first embodiment is omitted.

  In the first embodiment, in step S109 or step S110 in FIG. 11, immediately after the preliminary ejection after recording is performed, the idle suction is uniformly performed in step S111. However, since idle suction is a suction operation that attempts to discharge all the ink accumulated in the cap, idle suction requires time. In the present embodiment, the time required for the idle suction can be reduced according to conditions.

  Characteristic control according to the present embodiment will be described with reference to the flowchart of FIG. Here, Steps S201 to S210 are the same as Steps S101 to S110 of FIG. 11 described in the first embodiment, and thus description thereof is omitted.

  In this embodiment, after performing normal post-recording preliminary ejection (2000 nozzles for each color) in step S209, normal idle suction is performed in step S211. In this idle suction, the suction pump is driven for 5 seconds. On the other hand, in step S210, after pre-recording preliminary ejection (1000 nozzles for each color) with a small number of ejections is performed, in step S212, idle suction with a drive time shorter than normal idle suction is performed. In this idle suction, the suction pump is driven for 1 second. In this way, when the deposition suppressing ink is not so thickened, the ink is easily sucked by empty suction or penetrates into the cap absorber by its own weight, so that the short empty suction time (driving time) Thus, the ink in the cap can be sucked and discharged. Here, when the accumulation suppressing ink is not so thickened, the idle suction time is reduced. However, the idle suction time may be omitted.

  As described above, according to the present embodiment, when the amount of accumulated ink used in the recording operation is larger than a predetermined amount, or when the recording time is shorter than the predetermined time, the amount of ink ejected in the preliminary ejection after recording. And further reduce the idle suction time. Accordingly, it is possible to reduce the ink consumption used for suppressing the ink accumulation while suitably suppressing the ink accumulation on the cap, and further suppress the decrease in the throughput due to the idle suction.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to the drawings. The description of the same configuration as that in the above embodiment is omitted.

  In the above-described embodiment, the configuration has been described in which the accumulation of ink ejected to the cap by the pre-recording pre-discharge before the start of the recording operation is suppressed by the post-recording pre-discharge after the end of the recording operation. In the present embodiment, a configuration will be described in which the accumulation of ink ejected to the platen in the borderless recording operation is suppressed by post-recording preliminary ejection after the recording operation is completed.

  Hereinafter, the control when performing the borderless recording operation will be described.

  FIG. 13 is a schematic diagram showing a relationship between a recording medium and a platen absorber when performing a borderless recording operation in the present embodiment. The platen 300 is provided to extend in the moving direction of the carriage 100 in order to support the recording medium P being conveyed from below. When performing the borderless recording operation, the recording head 101 also ejects ink to a position beyond the end of the recording medium P (outside the recording medium). Further, the recording head 101 performs a preliminary ejection operation for ejecting ink that does not contribute to recording to the outside of the recording medium in order to discharge the thickened ink inside.

  The platen 300 is provided with a platen absorber (ink absorber, ink receiving portion) 301 that accommodates the ejected ink that protrudes from the outside of the recording medium. The ink stored in the platen absorber 301 is then discharged from below the platen 300 and discharged (collected) to a waste ink storage portion 504 provided at the lower part of the recording apparatus main body. In this embodiment, when performing a borderless recording operation, ink is ejected by the recording head 101 to a region that protrudes about 3 mm outside the size of the recording medium.

  FIG. 14 is a schematic diagram for explaining the count area of the accumulated ink when the borderless recording operation is performed in the present embodiment. In the present embodiment, as described above, when performing the borderless recording operation, even for an area that protrudes by 3 mm from the front end, the rear end, the right end, and the left end of the area P of the recording medium. Ink is ejected. In FIG. 14, such protruding regions are indicated by hatching, and are classified into a leading end protruding region, a trailing end protruding region, a right end protruding region, and a left end protruding region, respectively. The ink ejected to the right end protruding area and the left end protruding area is absorbed by the right end area and the left end area of the platen absorber 301 shown in FIG. Further, the ink ejected to the front end protruding area and the rear end protruding area is absorbed by the front rear end area of the platen absorber 301 shown in FIG. Note that the division of each region is not limited to the above example, and may be further finely divided.

When the CPU 1000 receives a recording command for performing a borderless recording operation from the host device, the CPU 1000 calculates the number of accumulated ink dots ejected to the protruding area. In calculating the number of dots of accumulated ink, the number of ink dots ejected to the right end area of the platen absorber 301, the number of ink dots ejected to the left end area, and the ink dots ejected to the front and rear end areas Count the number for each ink type. Then, the number of accumulated dots is calculated by subtracting the number of dots of the pigment ink that is the accumulation inhibiting ink from the count result of the pigment ink that is the accumulated ink. That is,
Number of accumulated dots = number of cyan dots + number of magenta dots + number of yellow dots + number of black dots + number of red dots-(number of light cyan dots + number of light magenta dots + number of gray dots + number of clear ink dots)
It becomes. In the present embodiment, information on the deposition state of the deposited ink in each region of the platen absorber 301 is obtained by calculating the number of accumulated dots, which is the difference between the number of accumulated ink dots and the number of accumulated ink suppression dots. did. However, for example, only the number of dots of pigment ink may be calculated. In this embodiment, the number of ejections of the deposited ink is counted, but the ejection amount of the accumulated ink, the ratio thereof, and the like may be calculated.

  The CPU 1000 refers to a table stored in the ROM 1001 in advance, and determines the number of deposited suppression ink ejections (number of dots) ejected to each area from the calculated number of accumulated dots in each area. Can do. The number of deposited dots and the number of ejected deposition suppression inks are used in the control described later.

  Deposition suppression control (backward control) for discharging the deposition suppression ink to the deposition ink will be described with reference to FIG. When the borderless recording operation is completed, in step S331, the carriage 100 is moved to a position (predetermined position) opposite to the area on the platen where ink has been ejected by the borderless recording operation. In step S332, the number of dots of accumulation suppression ink calculated in advance by the method described above is acquired. Specifically, the number of accumulated suppression ink dots is calculated by multiplying the acquired accumulated dot number by a predetermined coefficient B by the following equation.

Number of dots of deposition suppression ink to be ejected (backward amount AT) = coefficient B × number of deposited dots
The coefficient B is a coefficient set by examining and evaluating in advance the effect when the deposition suppressing ink is ejected with respect to the deposited ink. Here, the number of accumulated dots and the number of accumulated ink for suppressing deposition are calculated as a proportional relationship. Since the accumulation of ink is highly dependent on the environment, the coefficient B may be a coefficient that varies depending on the environment such as temperature and humidity. In the present embodiment, the number of accumulated dots and the number of ejected dots of accumulation suppression ink are calculated and acquired from the recording data before the start of the recording operation, but may be calculated after the end of the recording operation. For example, it may be calculated in step S332.

  In step S333, the deposition suppression ink is ejected for the ejection amount of the deposition suppression ink acquired in step S332. Here, in order to suppress the accumulation of ink over a wide area on the platen absorber, such as the front and rear end area in FIG. 13, the accumulation inhibiting ink is ejected while reciprocating the carriage a plurality of times. Also good. In addition, when it is intended to suppress ink accumulation in a narrow area, the carriage may be stopped on the area to discharge the accumulation suppression ink. When the ejection of the deposition suppression ink is finished, the trailing control is finished.

  In the present embodiment, the suppression of the accumulation of ink ejected to the protruding area of the platen absorber by the borderless recording operation has been described. However, the present invention may be applied to suppress accumulation of ink ejected to the platen absorber by the preliminary ejection operation.

  Next, control according to the present embodiment will be described with reference to the flowchart of FIG. In step S301, a recording command for recording a borderless image is received from the CPU 1000. When the recording command is received, the process proceeds to the next step S302, where the recording head 101 moves to a position facing the cap 500 by the carriage 100, and performs preliminary ejection before recording. Thereby, the thickening of the ink of each color can be sufficiently eliminated before the recording operation. Next, the process proceeds to step S303, where the measurement of the consumption and recording time of the deposition suppression ink (clear ink in this embodiment) is started. In step S304, the borderless recording operation for recording the borderless image related to the recording command on the recording medium is started. When the borderless recording operation is completed, in step S305, the measurement of the consumption of the deposition suppressing ink and the recording time are ended. In step S306, a wiping operation for wiping the ejection port surface of the recording head 101 is performed for the purpose of removing ink and paper dust adhering to the ejection port surface of the recording head 101.

  Next, in step S307, it is determined whether or not the measured recording time is longer than a predetermined time Tth. If the recording time is longer than the predetermined time Tth, the process proceeds to step S308. In step S308, it is determined whether or not the measured consumption of the deposition suppression ink is greater than a predetermined number of dots Dth. When the consumption amount of the accumulation suppression ink is less than the predetermined number of dots Dth, the process proceeds to step S309. At this time, the moisture of the deposition suppressing ink evaporates from the ejection port, and the ink thickens. Even if such accumulation suppressing ink lands on the platen absorber, the effect of suppressing ink accumulation may be reduced. Therefore, in step S309, the usual rearward control as described above is performed. In the post-printing control, since a sufficient amount of discharge is set in consideration of the evaporation of the deposition-suppressing ink, the post-printing control can suppress ink accumulation on the platen absorber.

  On the other hand, if the recording time is shorter than the predetermined time Tth in step S307, or if the consumption amount of the deposition suppression ink is larger than the predetermined number of dots Dth in step S308, the process proceeds to step S310. In step S310, the post-flow control of the discharge amount smaller than the discharge amount in the normal post-control described above is performed. In the trailing control, the trailing amount (1/2 AT) is set to half the trailing amount AT in the normal trailing control.

  Here, for the sake of simplicity of explanation, in the post-control, only the clear ink is used as the deposition suppression ink, but the same calculation and control are performed using the deposition suppression ink such as other light cyan ink and light magenta ink. It is good also as a structure to perform.

  Further, in the post-control in which the back amount is reduced, the back amount is half that of the normal back control, but the normal back amount is multiplied by the coefficient K, and the coefficient K is set to the recording time or recording. It is good also as changing according to the consumption of the deposition suppression ink in operation | movement, etc.

  As described above, according to the present embodiment, when the ink amount of the deposition suppressing ink used in the recording operation is larger than the predetermined amount, or when the recording time is shorter than the predetermined time, it is delayed after the end of the recording operation. The amount of ink ejected in the control is reduced than usual. Accordingly, it is possible to reduce the ink consumption used for suppressing the ink accumulation while suitably suppressing the ink accumulation on the platen.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 101 Recording head 300 Platen 301 Platen absorber 500 Cap 501 Cap absorber

Claims (15)

A recording head that performs a recording operation of recording an image on a recording medium by discharging a first ink in which ink accumulation occurs and a second ink that suppresses the ink accumulation;
An ink receiving portion for receiving ink ejected from the recording head;
First ejection control for ejecting a specified amount of ink to the ink receiving portion before performing the recording operation when a recording command is issued, and ejection in the first ejection control after performing the recording operation An ink jet recording apparatus comprising: control means for performing second discharge control for discharging the first ink and the second ink to the ink receiving portion in order to suppress accumulation of the ink that has been performed. There,
In the second ejection control, the control unit determines an ink amount to be ejected when the ejection amount of the first ink in the recording operation is larger than a predetermined amount, and the ejection amount of the first ink is the predetermined amount. An ink jet recording apparatus characterized in that the amount of ink ejected when the amount is smaller is smaller.   In the second ejection control, the control means sets the ink amount to be ejected when the recording time required for the recording operation is shorter than a predetermined time, than the ink amount to be ejected when the recording time is longer than the predetermined time. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is also reduced. A cap for covering the discharge port surface of the recording head;
The inkjet recording apparatus according to claim 1, wherein the ink receiving portion is a cap absorber disposed on the cap.   4. The ink jet recording apparatus according to claim 1, further comprising a wiper that wipes an ejection port surface of the recording head before performing the second ejection control. 5.   The inkjet recording apparatus according to claim 1, further comprising a suction pump that performs a suction operation of sucking ink in the ink receiving portion after performing the second ejection control.   In the suction operation, the suction pump indicates a drive time when the discharge amount of the first ink in the recording operation is greater than the predetermined amount, and indicates a drive time when the discharge amount of the first ink is less than the predetermined amount. 6. The ink jet recording apparatus according to claim 5, wherein the driving time is shorter than the driving time.   In the second ejection control, the control means makes the amount of ink ejected when the environmental temperature is lower than a predetermined temperature be smaller than the amount of ink ejected when the environmental temperature is higher than the predetermined temperature. An ink jet recording apparatus according to any one of claims 1 to 6.   In the second ejection control, the control means makes the amount of ink ejected when the environmental humidity is higher than a predetermined humidity be smaller than the amount of ink ejected when the environmental humidity is lower than the predetermined humidity. An ink jet recording apparatus according to any one of claims 1 to 7. A recording head that performs a recording operation of recording an image on a recording medium by discharging a first ink in which ink accumulation occurs and a second ink that suppresses the ink accumulation;
An ink receiving portion for receiving ink ejected from the recording head;
An ink jet recording apparatus comprising: control means for performing discharge control for discharging the second ink to the ink receiving portion in order to suppress ink accumulation in the ink receiving portion after performing the recording operation. And
In the ejection control, the control means determines an ink amount to be ejected when the ejection amount of the second ink in the recording operation is larger than a predetermined amount, and an ejection amount of the second ink is smaller than the predetermined amount. An ink jet recording apparatus characterized in that the amount of ink discharged is less than that of the ink jet recording apparatus.   In the ejection control, the control means reduces the amount of ink ejected when the recording time required for the recording operation is shorter than a predetermined time than the amount of ink ejected when the recording time is longer than the predetermined time. The inkjet recording apparatus according to claim 9. A platen for supporting the recording medium from below;
The inkjet recording apparatus according to claim 9, wherein the ink receiving portion is a platen absorber disposed on the platen. The recording head performs a borderless recording operation for recording an image by discharging ink to the outside of the recording medium,
The ink jet recording apparatus according to claim 9, wherein the ink receiving portion receives ink ejected in the borderless recording operation.   The control means is determined based on a discharge amount of the first ink discharged to the ink receiving portion and a discharge amount of the second ink discharged to the ink receiving portion in the discharge control. The inkjet recording apparatus according to claim 9, wherein the second ink is ejected in an amount of ink. The first ink is at least one of magenta ink, cyan ink, yellow ink, black ink, and red ink,
The inkjet recording apparatus according to claim 1, wherein the second ink is at least one of light cyan ink, light magenta ink, and clear ink. The inkjet recording apparatus according to claim 1, wherein the first ink is a pigment ink, and the second ink is a dye ink.

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