JP2012016957A - Liquid discharging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise visibility of an image edge without complicated control.SOLUTION: When a flushing dot region where flushing dots are formed is located in an exclusion range within at least one dot region from an edge dot region corresponding to an edge of an image engaged with the image data memorized in an image data storage part, the flushing dot region is moved out of the exclusion region to a downstream side in a forward carrying direction.

Description

  The present invention relates to a liquid ejection apparatus including a recording head that ejects ink droplets to form image dots and flushing dots on a recording medium.

  In general, in an ink jet printer having an ink jet head that ejects ink droplets from a plurality of ejection ports, in order to prevent ink clogging due to the ink in the vicinity of the ejection ports being solidified, separately from the ink droplets that form an image, Preliminary ejection for ejecting thickened ink is performed. Patent Documents 1 and 2 disclose a printer in which preliminary ejection is performed in parallel with image formation, and flushing dots are formed on a recording medium by ink ejected by preliminary ejection.

  In the printer of Patent Document 1, the flushing dots are made inconspicuous by forming the flushing dots in the vicinity of the image dots constituting the image. Further, in the printer of Patent Document 2, when the flushing dot formation scheduled position is adjacent to the image dot, the image dot formation position is moved to the flushing dot formation planned position, and the flushing dot formation is stopped. Thereby, the flushing dots are mixed with the image dots located in the vicinity thereof, so that a high density portion is generated in the image and the image is prevented from deteriorating.

JP 2008-179011 A JP 2007-185957 A

  However, when the flushing dot is formed in the vicinity of the image dot as in the above-mentioned Patent Document 1, the flushing dot is perceived as a part of the image edge (the contour portion of the image), the image edge is disturbed, and the image edge There arises a problem that the visibility of is reduced. Further, as in Patent Document 2, it is complicated to control the formation position of the image dot to the formation position of the flushing dot.

  Therefore, an object of the present invention is to provide a liquid ejection apparatus that does not require complicated control and can improve the visibility of an image edge.

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. A first ejection head having first energy application means for applying ejection energy for ejecting liquid; image data input from the outside; a first distance corresponding to a recording resolution in an orthogonal direction orthogonal to the transport direction; Image data storage means for storing data for discharging the first liquid in a plurality of dot areas defined on the recording medium at a second distance corresponding to the recording resolution in the transport direction; and the image data storage means Image recording control means for controlling the first energy application means of the first ejection head based on the image data stored in the image data, and the image data among the plurality of dot areas. The preliminary reserve of the first liquid so that the first liquid lands at a position away from the edge dot area, which is the dot area corresponding to the edge of the image related to the image data stored in the storage means, by at least one dot area. Preliminary ejection data creation means for creating preliminary ejection data related to ejection, and the first flushing dots are formed on the recording medium based on preliminary ejection data for the first liquid created by the preliminary ejection data creation means. And a flushing control means for controlling the first energy application means of the ejection head.

  Note that “the dot area corresponding to the edge of the image” means that at least one of the dot areas stored as the area where the first liquid lands in the image data lands on the adjacent dot area. This is a dot area where there is a non-performing dot area.

  According to the above-described configuration, it is possible to prevent the flushing dot from being perceived as a part of the image edge and disturbing the image edge by preventing the flushing dot from being formed in the vicinity of the edge of the image. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control.

  In the liquid ejection apparatus according to the aspect of the invention, the preliminary ejection data creation unit further includes a range determination unit that determines the predetermined range, and creates the preliminary ejection data based on the predetermined range determined by the range determination unit. It is preferable to do. According to this configuration, the predetermined range can be appropriately determined according to the content of the image, the printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved.

  In the liquid ejection apparatus according to the aspect of the invention, it is preferable that the range determination unit determines the predetermined range so that the predetermined range becomes wider as the first liquid that has landed on the recording medium easily spreads. When the first liquid that has landed on the recording medium spreads over a wide range due to bleeding, the image edge is likely to be disturbed by the flushing dots formed in the vicinity of the edge dot region. According to the above-described configuration, when the blur is likely to occur, the visibility of the image edge can be reliably improved by widening the predetermined range.

  In the liquid ejection apparatus of the present invention, the image recording control unit controls the first ejection energy applying unit of the first ejection head based on conversion data obtained by converting the image data by an error diffusion method, and determines the range. The means preferably determines the range in which the error of the image data corresponding to the edge dot region is distributed as the predetermined range. According to this configuration, it is possible to prevent the flushing dots formed in the vicinity of the edge dot region from being overlapped with the image dots formed by error diffusion.

  In the liquid ejection apparatus according to the aspect of the invention, it is preferable that the range determination unit determines the predetermined range so that the predetermined range becomes wider as a line of an image including data corresponding to the edge dot region is thinner. According to this configuration, the visibility of the image edge can be reliably improved when the image is a relatively thin line and it is important to keep the visibility of the image edge high.

  In the liquid ejection apparatus according to the aspect of the invention, the range determination unit may compare the brightness of the image dots formed in the edge dot region located closest to the dot region where the flushing dots are formed, as compared with the brightness of the flushing dots. It is preferable that the predetermined range is determined so that the predetermined range becomes wider as the value is larger. According to this configuration, even when the brightness of the image dots formed in the edge dot area is larger than the brightness of the flushing dots and the flushing dots are easily noticeable, it is difficult to stand out by forming the flushing dots away from the edge dot area. can do.

In the liquid ejection apparatus of the present invention, a second ejection port that ejects a second liquid that is ejected onto the recording medium and promotes fixing of the first liquid onto the recording medium, and the second ejection port To second
A second ejection head having second ejection energy applying means for applying ejection energy for ejecting liquid and a second liquid for generating ejection data of the second liquid based on the image data stored in the image data storage means A liquid ejection data creating unit; and a second liquid control unit for controlling the second ejection energy applying unit of the second ejection head based on the ejection data created by the second liquid ejection data creating unit. Preferably, the range determining means determines the predetermined range so that the larger the amount of the second liquid that is landed on the edge dot region by the control of the second liquid control means, the wider the predetermined range. .

  According to this configuration, the second liquid acts on the area where the flushing dots are formed on the recording medium, the fixing of the flushing dots is promoted, and the flushing dots can be prevented from being noticeable.

  In the liquid ejection apparatus of the present invention, a second ejection port that ejects a second liquid that is ejected onto the recording medium and promotes fixing of the first liquid onto the recording medium, and the second ejection port The second liquid discharge data is generated based on the second discharge head having the second discharge energy applying means for applying the discharge energy for discharging the second liquid from the image data and the image data stored in the image data storage means. Second liquid discharge data generating means for controlling the second discharge energy applying means of the second discharge head based on the discharge data generated by the second liquid discharge data generating means. Further, the range determining means is adjacent to the edge dot region and the wider the range in which the second liquid discharged by the control to the second liquid control means is landed, It is preferable to determine the predetermined range as the constant range is widened.

  According to this configuration, the fixing of the flushing dots is promoted by the second liquid that has landed in the vicinity of the edge dot region, and the flushing dots can be prevented from being noticeable.

  In the liquid ejection apparatus according to the present invention, the preliminary ejection data creation means may prevent the first liquid from being present in the first ejection port where the non-ejection time during which the first liquid is not ejected is a predetermined time or longer. Initial data creation means for creating the initial preliminary ejection data, and when the first liquid ejected based on the initial preliminary ejection data created by the initial data creation means lands within the predetermined range, There may be provided change means for changing the preliminary preliminary discharge data so that the non-discharge time of the first discharge port from which the first liquid is discharged becomes shorter than before the change.

  According to this configuration, the non-ejection time of the first ejection port can be kept shorter than a predetermined time, and the visibility of the image edge can be improved while ensuring the ejection performance.

  In the liquid ejection apparatus according to the aspect of the invention, the changing unit may change the preliminary ejection data other than the preliminary ejection data to be changed when the preliminary ejection data is changed so that the non-ejection time of the first ejection port becomes shorter than before the change. The data may be changed so that there is no first discharge port in which the non-discharge time during which the first liquid is not discharged is a predetermined time or longer. According to this configuration, when the non-ejection time of the first ejection port is changed to be short, a portion where the non-ejection time becomes longer in the other preliminary ejection data is generated, and it is possible to prevent the ejection performance from being deteriorated.

  In the liquid ejection apparatus according to the aspect of the invention, the preliminary ejection data creation unit may create preliminary ejection data so that dot areas where flushing dots are formed are not adjacent to each other. According to this structure, it can prevent that flushing dots adjoin and stand out.

The liquid ejection apparatus according to the present invention further includes a double-sided printing mechanism for recording images on both sides of the recording medium, and the preliminary ejection data creation means includes a dot area where the first liquid ejected by the preliminary ejection lands. However, the preliminary discharge data of the first liquid may be created so that the two sides of the recording medium do not overlap. According to this configuration, it is possible to prevent the flushing dots from conspicuous by overlapping on both sides of the recording medium.

  In the liquid ejection apparatus according to the aspect of the invention, it is preferable that the first ejection head is a line-type head that extends in the orthogonal direction and is fixedly provided. In the case of a line-type head that is fixedly provided, it is particularly necessary to eject the first liquid onto the recording medium during preliminary ejection. Therefore, according to the above configuration, the application of the present invention is useful.

  As described above, in the liquid ejection device of the present invention, by preventing the formation of flushing dots in the vicinity of the edge of the image, it is possible to prevent the flushing dot from being perceived as part of the image edge and disturbing the image edge. can do. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control.

1 is a schematic side view showing an overall configuration of an ink jet printer according to a first embodiment of the present invention. It is a top view of the head main body shown in FIG. FIG. 3 is an enlarged view of a region surrounded by an alternate long and short dash line in FIG. 2. FIG. 3 is a partial cross-sectional view of the head body shown in FIG. 2. It is a functional block diagram of the control apparatus shown in FIG. It is a figure explaining the production | generation of the print data in the print data production | generation part shown in FIG. It is a figure which shows the process of determining the area | region which forms a flushing dot in the flushing data preparation part shown in FIG. It is a flowchart which shows an example of the process sequence performed in the flushing data creation part shown in FIG. It is a flowchart which shows the modification of the process sequence performed in the flushing data creation part of embodiment of this invention.

  A preferred embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the ink jet printer 101 has a rectangular parallelepiped casing 101a. In the housing 101a, the paper P is disposed in two directions, a forward transport direction (right direction in FIG. 1) and a reverse transport direction opposite to the forward transport direction, and the transport mechanism 16 is disposed above the transport mechanism 16. The four recording heads 1a and the processing liquid discharge head 1b are provided. The four recording heads 1a eject cyan, magenta, yellow, and black ink (first liquid) onto the paper P that is transported in the forward transport direction by the transport mechanism 16, respectively. The processing liquid discharge head 1b is located upstream of the four recording heads 1a in the forward transport direction, and applies the processing liquid (second liquid) to the paper P transported in the forward transport direction by the transport mechanism 16. Discharge. Since the recording head 1a and the processing liquid discharge head 1b have substantially the same configuration, in the following description, they may be simply referred to as “head 1” without distinction.

  Here, the treatment liquid used in the present embodiment is applied to the paper P in advance to reduce the penetrability of the ink adhered later into the paper P. As a result, the ink can be easily fixed on the paper P. A processing liquid that improves the coagulation property of the ink on the paper P by landing on the previously ejected ink, that is, a post-processing liquid may be used. In this case, the treatment liquid discharge head 1b is disposed on the downstream side of the four recording heads 1a in the forward transport direction.

  In addition, a paper discharge unit 15 for discharging the paper P on which an image is formed is provided on the top of the top plate of the housing 101a. Further, a sheet feeding unit 101b is disposed below the transport mechanism 16, and a tank unit 101c is disposed below the sheet feeding unit 101b. In the tank unit 101c, four ink tanks 17a and one processing liquid tank 17b are accommodated. In addition, on the upstream side of the processing liquid discharge head 1b with respect to the forward transport direction, when printing on both sides of the paper P, there is a double-side printing mechanism 24 that reverses the front and back of the paper P on which an image is recorded on one side. Has been placed.

  A main conveyance path is formed along the thick black arrow shown in FIG. 1 inside the inkjet printer 101, and the paper P is conveyed from the paper supply unit 101 b toward the paper discharge unit 15. The paper feed unit 101 b includes a paper feed tray 11 and a paper feed roller 12. The paper feed tray 11 has a box shape opened upward, and stores a plurality of paper sheets P in a stacked state. The paper feed roller 12 sends out the paper P at the uppermost position of the paper feed tray 11. The fed paper P is guided to the transport mechanism 16 while being guided by the guides 13 a and 13 b and sandwiched by the feed roller pair 14.

  The transport mechanism 16 includes two belt rollers 6 and 7, a transport belt 8, a tension roller 10, and a platen 18. The conveyor belt 8 is an endless belt wound around the rollers 6 and 7, and tension is applied by a tension roller 10. The platen 18 is disposed in an inner region of the conveyance belt 8 and supports the conveyance belt 8 at a position facing the recording head 1a and the treatment liquid ejection head 1b. The belt roller 7 is a driving roller that is driven to rotate in two directions, clockwise and counterclockwise in FIG. 1 by a motor (not shown), and the belt roller 6 is driven by the rotation of the belt roller 7. This is a driven roller that rotates as a result. Therefore, the transport mechanism 16 can transport the paper P placed on the transport belt 8 in the forward transport direction and the reverse transport direction by switching the drive of the motor that drives the belt roller 7.

  The paper P sent out from the transport mechanism 16 in the forward transport direction is guided by the guide 29 a and is sandwiched between the pair of feed rollers 27. The two-feed roller pair 27 includes a driving roller 27a that is driven to rotate in two directions clockwise and counterclockwise in FIG. 1 by a motor (not shown), and a driven roller 27b that is driven to rotate as the driving roller 27a rotates. Become. As a result, the pair of feed rollers 27 can feed the sandwiched paper P in two directions, the forward transport direction and the reverse transport direction.

  The paper P fed in the forward transport direction by the pair of feed rollers 27 is guided by the guide 29b and transported while being sandwiched by the pair of feed rollers 28, and discharged from the discharge port 22 formed in the upper part of the housing 101a. It is discharged to the part 15. On the other hand, the paper P transported in the reverse transport direction by the pair of feed rollers 27 is sent to the transport mechanism 16 again. At this time, the transport mechanism 16 is in a state of transporting the paper P in the reverse transport direction under the control of the control device 100 described later. Accordingly, the paper P sent to the transport mechanism 16 is transported in the reverse transport direction, and is sent to the duplex printing mechanism 24 on the downstream side of the processing liquid ejection head 1b in the reverse transport direction.

  The double-sided printing mechanism 24 is mainly composed of a plurality of refeed roller pairs 25 and a plurality of guides 26 for guiding the paper P between them, and both ends as indicated by white thick arrows in FIG. The paper P is transported along a loop-like inversion path connected to the. More specifically, in the double-sided printing mechanism 24, the paper P is conveyed along the reverse path in a state where the front side is the outside before being sent to the double-sided printing mechanism 24. Therefore, the sheet P conveyed by the conveyance mechanism 16 in the reverse conveyance direction in the reverse conveyance direction and sent to the double-side printing mechanism 24 is again printed between the conveyance mechanism 16 and the feed roller pair 14 with the front and back sides reversed. Sent to the transport path.

  The five heads 1 have a substantially rectangular parallelepiped shape that is long in the main scanning direction. These heads 1 are arranged and fixed along the transport direction of the paper P. That is, the printer 101 is a line printer, and the transport direction and the main scanning direction are orthogonal to each other. The four recording heads 1a are arranged in the order of cyan, magenta, yellow, and black from the upstream side in the forward transport direction.

  Each head 1 has a head body 2 in which a plurality of ejection openings 108 (see FIGS. 3 and 4) for ejecting ink are formed. The four ink tanks 17a store inks of different colors, and the processing liquid tank 17b stores processing liquid. Cyan, magenta, yellow, and black ink and processing liquid are supplied from the ink tank 17 a and the processing liquid tank 17 b to the head body 2.

  The ejection port 108 is open to the ejection surface 2 a that is the lower surface of the head body 2, and the ink supplied to the head body 2 reaches. When the paper P transported in the forward transport direction by the transport mechanism 16 passes just below the five heads 1, the processing liquid is first supplied from the discharge port 108 toward the upper surface of the paper P, and then the ink of each color is supplied. It discharges in order. As a result, a desired color image is formed on the upper surface of the paper P, that is, the surface facing upward on the transport belt 8. The ejection surface 2a is also a long plane in the main scanning direction. Further, the ejection ports 108 are arranged along the main scanning direction of the ejection surface 2a in a range not less than the length along the main scanning direction of the paper P so that an image can be formed on the entire paper P.

  Next, the head main body 2 will be described in detail with reference to FIGS. In FIG. 3, for convenience of explanation, the pressure chamber 110, the aperture 112, and the discharge port 108 that are to be drawn by broken lines below the actuator unit 21 are drawn by solid lines.

  As shown in FIG. 2, the head body 2 is a laminated body in which four actuator units 21 are fixed to the upper surface 9 a of the flow path unit 9. Although not shown, the recording head 1a and the treatment liquid discharge head 1b are driven by a reservoir unit that stores ink (or treatment liquid) supplied to the flow path unit 9 and the actuator unit 21 in addition to the head body 2. It includes a flexible printed circuit (FPC) for supplying signals, a control board for controlling a driver IC mounted on the FPC, and the like.

  As shown in FIG. 4, the flow path unit 9 is a laminated body in which a plurality of metal plates made of stainless steel are aligned with each other. In the flow path unit 9, there are many manifold channels 105 (see FIGS. 2 and 3) to the sub manifold flow path 105a, and from the outlet of the sub manifold flow path 105a to the discharge port 108 through the aperture 112 and the pressure chamber 110. The individual ink flow paths 109 are formed. The actuator unit 21 includes a plurality of actuators corresponding to the pressure chambers 110, and has a function of selectively giving ejection energy to the ink in the pressure chambers 110.

  As shown in FIG. 2, a total of ten ink supply ports 105b are opened on the upper surface 9a of the flow path unit 9 corresponding to the ink outflow flow paths of the reservoir unit. The lower surface of the flow path unit 9 is a discharge surface 2a, and a large number of discharge ports 108 are arranged in a matrix. The ejection ports 108 are arranged at an interval of 600 dpi, which is the resolution in the main scanning direction with respect to the main scanning direction.

The recording head 1a and the processing liquid discharge head 1b each have the head body 2 as described above. The recording head 1a includes an image recording control unit 35 and a flushing control unit 36, which will be described later, and the processing liquid discharge head 1b. By the control of the precoat control unit 40 to be described later, the discharge interval of the ink or the processing liquid is controlled so that the ink or the processing liquid from the discharge port 108 lands on the paper P at an interval of 600 dpi in the sub-scanning direction. That is, in the present embodiment, the resolution in the main scanning direction and the resolution in the sub scanning direction are both 600 dpi, and the paper P is partitioned in a grid pattern with an interval of 1/600 inch in the main scanning direction and the sub scanning direction. A plurality of dot areas are defined.

  In the present embodiment, the recording head 1a is controlled by an image recording control unit 35 and a flushing control unit 36, which will be described later, so that the amount of ink ejected from the ejection port 108 is large, medium, and small. Adjusted in three stages of drops. Similarly, with respect to the processing liquid discharge head 1b, the amount of the processing liquid discharged from the discharge port 108 is adjusted in three stages of large droplets, medium droplets, and small droplets by the control of the precoat control unit 40 described later. .

Returning to FIG. 1, a control device 100 for controlling the entire inkjet printer 101 is disposed in the housing 101a. Here, the control device 100 will be described with reference to FIG. The control device 100 includes a CPU (Central Processing Unit), a program executed by the CPU and an EEPROM (Electrically Erasable and Programmable Read Only Memory) that stores data used for the program in a rewritable manner, and stores data when the program is executed. It includes RAM (Random Access Memory) for temporary storage. Each functional unit constituting the control device 100 is constructed by cooperation of these hardware and software in the EEPROM. As shown in FIG. 5, the control device 100 includes a conveyance control unit 31, an image data storage unit 32, a print data generation unit 33, a print data storage unit 34, an image recording control unit 35, a flushing control unit 36, and a flushing data creation unit. 37, a lightness calculation unit 38, a lightness determination unit 39, a precoat control unit 40, and a precoat data creation unit 41.

  The conveyance control unit 31 includes a plurality of motors (not shown) that respectively drive the paper feed roller 12, the feed roller pair 14, the belt roller 7, the both feed roller pair 27, the feed roller pair 28, and the refeed roller pair 25. To control. More specifically, when an image is recorded on only one side of the paper P, the paper P stored in the paper feed tray 11 is sent out and passed between the five heads 1 and the conveyor belt 8, and the discharge port 22. To discharge. When images are recorded on both sides of the paper P, the paper P conveyed from the paper feed tray 11 to the downstream side of the head 1 along the sending forward conveyance direction is conveyed in the reverse conveyance direction, and the double-side printing mechanism 24 After reversing the front and back, it is conveyed again in the forward conveying direction and discharged to the discharge port 22.

The image data storage unit 32 stores image data transferred from a PC (Personal Computer) or the like connected to the inkjet printer 101. This image data is expressed by, for example, a CMYK color model. Each dot data included in the image data is associated with a plurality of dot areas on the paper P, and has gradation values of cyan, magenta, yellow, and black, each represented by 0 to 255. Yes. In this embodiment, the size of the image data is data for each page of the paper P for single-sided printing, and data for two pages (double-sided) for the paper P for double-sided printing. However, the range of the image data of the present invention is not limited to this embodiment, and may be data of less than one page of the paper P in the case of single-sided printing.

The print data generation unit 33 uses an error diffusion method to calculate a gradation value corresponding to the ink amount of each color ink to be landed on each dot area from each dot data of the image data stored in the image data storage unit 32. Print data that is the dot data shown is generated. Specifically, whether or not the ink is landed for each color in each dot area by converting the gradation information of the dot data included in the image data into four values using three types of threshold values, large, medium, and small. When ink is landed, print data representing whether the amount is large, medium, or small is generated. For each dot data, an error between the gradation value in the image data and the gradation value corresponding to the ink amount in the print data is calculated, and the dot data corresponding to the dot area around the dot area corresponding to the dot data. To distribute. In this embodiment, the error is distributed to dot data corresponding to the range of one dot area around the dot area corresponding to the target dot data.

  As described above, in the present embodiment, the error diffusion method is used when generating print data from image data. Therefore, as shown in FIG. An error dot area (area indicated by “D” in the figure) to which an error between the gradation value in the image data and the gradation value in the print data is distributed is arranged around (indicated by black in the figure) Is done. In other words, the error dot area is arranged in a range from the edge dot area to the one dot area where the background dot area corresponding to the background (area indicated by white painting) exists in the adjacent dot area among the image dot areas. Is done.

  The print data storage unit 34 stores the print data generated by the print data generation unit 33. The image recording control unit 35 controls each actuator included in the actuator unit 21 provided in each recording head 1 a based on the print data stored in the print data storage unit 34.

  The flushing control unit 36 applies to each recording head 1 a based on the ink flushing data created by the flushing data creation unit 37 in order to perform flushing for ejecting the thickened ink near the ejection port 108 toward the paper P. Each actuator included in the provided actuator unit 21 is controlled.

  The flushing data creation unit 37 includes a data storage unit 37a, an initial data creation unit 37b, a change unit 37c, and a range determination unit 37d. The data storage unit 37a stores data related to the dot area that forms the flushing dot.

  The initial data creation unit 37b provisionally determines a flushing dot area that is a dot area for forming a flushing dot. Specifically, a flushing dot area is determined by a predetermined dot interval (distance) calculated by multiplying the conveyance speed of the paper P stored in the conveyance control unit 31 by a predetermined time, and the dot area is defined as a data storage unit. Store in 37a. That is, as shown in FIG. 7A, in the plurality of dot areas defined on the paper P, flushing dot areas (dot areas indicated by hatching in the figure) are provided for a predetermined dot interval along the forward conveyance direction. Are arranged at equal intervals apart from each other. Thereby, it is possible to prevent the ejection port 108 where the non-ejection time during which ink is not ejected is longer than the predetermined time from being present. The predetermined time varies depending on the ink color, ambient temperature, humidity, and the like.

  If there is a dot area stored in the data storage section 37a that is within the exclusion range determined by the range determination section 37d, the changing section 37c discharges ink to the dot area. The data in the data storage unit 37a is changed so that the predetermined dot interval is shorter than before the change. That is, the dot area located within the exclusion range is moved downstream in the forward transport direction (the direction in which the interval at which ink is ejected to the dot area is shortened, in other words, the direction in which ink is ejected quickly). At this time, in the case of other dot areas stored in the data storage unit 37a, the interval between the dot areas along the forward transport direction is equal to or greater than the predetermined dot interval, that is, the non-ejection time is the predetermined time. When there is a possibility that the above-described ejection port 108 exists, a flushing dot region is newly added so that there is no ejection port 108 whose non-ejection time is longer than a predetermined time.

In addition, when there are adjacent dot areas stored in the data storage unit 37a, the changing unit 37c changes any of the dot areas to a dot area on the downstream side in the forward transport direction. The data in the data storage unit 37a is changed.

  Furthermore, when the change unit 37c performs double-sided printing, if there are dot areas stored in the data storage unit 37a that overlap on both sides of the paper P, any one of those dot areas is in the forward transport direction. The data in the data storage unit 37a is changed so that the dot area is changed to the downstream dot area.

  The range determination unit 37d determines the size of the exclusion range. The exclusion range is an edge dot area that is a dot area corresponding to an edge of an image related to image data stored in the image data storage unit 32 (one of image dot areas where an image related to image data is formed). However, this is a predetermined range adjacent to a background dot area where an image is not formed). Specifically, the range determination unit 37d determines the error dot area as the exclusion range when none of the four conditions described below is satisfied. That is, at this time, the first area within one dot area from the edge dot area is the exclusion range. Further, when at least one of the four conditions is satisfied, a second area within 2 dot areas from the edge dot area is determined as an exclusion range. Hereinafter, four conditions will be described.

  The first condition is that ink that has landed on the paper P is likely to bleed. In the present embodiment, the ease of bleeding is determined based on the type of paper P, the type of ink, and the humidity of the paper P. Specifically, for example, data relating the type of paper P and ease of bleeding, that is, paper P that is likely to cause feathering and bleeding is stored as being easy to spread, and other paper P is difficult to spread. Is stored, and the ease of bleeding is determined from information on the type of the paper P obtained by detection by the paper type detection sensor or input by the user. Similar data is prepared for the type of ink and the humidity of the paper P, and is determined from information obtained by sensor detection or user input.

  The second condition is that a line of an image including data corresponding to the edge dot region located closest to the flushing dot region is thin. That is, if the thickness of the line of the image including data corresponding to the edge dot region is equal to or smaller than a predetermined threshold, the line is determined to be a thin line.

  The third condition is that the brightness of the image dot formed in the edge dot region located closest to the dot region where the flushing dot is formed is greater than the brightness of the flushing dot. In addition, the determination result of the lightness determination unit 39 is used for determining the lightness.

  The fourth condition is that the amount of treatment liquid that lands on the edge dot region located closest to the flushing dot region is large. In the present embodiment, when a large amount of processing liquid lands on the edge dot area, it is determined that the amount of processing liquid is large.

  The lightness calculation unit 38 calculates the lightness of the image dots and flushing dots formed on the paper P based on the color and amount of ink discharged from the discharge port 108 of each recording head 1a. Specifically, as shown in Table 1 below, the inks are weighted in order from the darkest color to 1 for black, 2 for magenta, 3 for cyan, 4 for yellow, and the amount of ink. In order from the largest amount, 1 is assigned to the large droplet, 2 is assigned to the middle droplet, and 3 is assigned to the small droplet, and the lightness is calculated by multiplying the weight of these colors and the weight of the amount. That is, for example, the lightness in the case of a yellow medium drop is (4 × 2 =) 8, and the lightness in the case of a black small drop is (1 × 3 =) 3.

  The lightness determination unit 39 determines the magnitude relationship between the lightnesses of two dots formed on the paper P based on the calculation result by the lightness calculation unit 38. That is, for example, when comparing an image dot formed with a yellow medium droplet and a flushing dot formed with a small black droplet, the brightness of the image dot is 8 and the brightness of the flushing dot is 3 as described above. Therefore, it is determined that the brightness of the flushing dot is smaller.

  The precoat control unit 40 controls each actuator included in the actuator unit 21 provided in the processing liquid ejection head 1b based on the data created by the precoat data creation unit 41. The precoat data creation unit 41 creates data relating to the dot area where the treatment liquid lands and the amount of the treatment liquid to be ejected. The pre-coat data creation unit 41 treats the processing liquid in a dot region where ink lands based on control of the image recording control unit 35 among a plurality of dot regions defined on the paper P, that is, a dot region where an image dot is formed. Create data so that will land. Further, the amount of the processing liquid to be ejected is determined so that the amount of the processing liquid increases as the amount of ink constituting the image dots formed in the dot region increases.

  Next, an example of a processing procedure performed by the flushing data creation unit 37 of the control device 100 when the printer 101 forms images on both sides of the paper P will be described with reference to FIG. Prior to this processing procedure, image data is stored in the image data storage unit 32 and processing liquid ejection data is created in the precoat data creation unit 41, and then the process of FIG. 8 is started. . In the present embodiment, the size of the image data stored in the image data storage unit 32 is one page or more of data on the paper P for single-sided printing, and one page or more for double-sided printing. The data is in units of 2 pages (both sides) and is related to even pages. However, the range of the image data of the present invention is not limited to this embodiment, and may be data of less than one page of the paper P in the case of single-sided printing.

  First, the initial data creation unit 37b flushes the stored image data so that flushing dots are formed on the paper P at a predetermined dot interval along the forward conveyance direction as shown in FIG. 7A. A dot area is provisionally determined (step S11). In the present embodiment, the flushing dot area is provisionally determined regardless of the image data. The provisional flushing data determined in step S11 is stored in the data storage unit 37a. Thereafter, from step S12 to step S21, each data included in the flushing data determined in step S11 is processed in order.

  Next, in order to determine the exclusion range by the range determination unit 37d, determination of four conditions is performed in order (steps S12 to S15). That is, first, it is determined whether or not the ink attached to the paper P is likely to bleed (step S12). Subsequently, it is determined whether or not the line of the image including the data corresponding to the edge dot region located closest to the dot region where the flushing dot is formed is thin (step S13). Further, it is determined whether or not the brightness of the image dots formed in the edge dot region located closest to the dot region where the flushing dots are formed is greater than the brightness of the flushing dots (step S14). Finally, it is determined whether or not the amount of the treatment liquid that has landed on the edge dot region located closest to the dot region where the flushing dots are formed is large (step S15).

  If none of the above four conditions is satisfied (NO in all of steps S12 to S15), the exclusion range is determined as the first region by the range determination unit 37d, and the dot region where the flushing dots are formed Is determined to be located in the first region (step S16). At this time, if it is not located in the first region (S16: NO), the process proceeds to step S24 described later. If it is located in the first region (S16: YES), the process proceeds to step S18.

  On the other hand, when at least one of the four conditions is met (YES in any of steps S12 to S15), the exclusion range is determined as the second region by the range determination unit 37d, and flushing dots are formed. It is determined whether or not the dot area is located in the second area (step S17). At this time, if it is not located in the second region (S17: NO), the process proceeds to step S24 described later. If it is located in the second area (S17: YES), the process proceeds to step S18.

  Next, the data in the data storage unit 37a is changed so that the flushing dot region located within the exclusion range moves out of the exclusion range toward the downstream side in the forward transport direction (step S18). Here, a flushing dot region surrounded by a broken-line circle in FIG. Such a flushing dot area is adjacent to an edge dot area of an image dot area (dot area surrounded by a thick line in the figure) where an image related to image data is formed. It is assumed that the exclusion range of the flushing dot area is within the second area, that is, within the 2 dot area from the edge dot area. Therefore, the flushing dot area moves by 2 dot areas downstream in the forward transport direction as shown in FIG. 7B by the processing in step S18.

  Subsequently, it is determined whether or not the flushing dot area moved in step S18 is adjacent to another flushing dot area (step S19). If it is adjacent to another flushing dot area (S19: YES), the process proceeds to step S21 to be described later. On the other hand, if they are not adjacent (S19: NO), it is determined whether or not the dot area moved in step S18 overlaps the flushing dot area on the opposite side of the paper P (step S20). If the flushing dot areas overlap on both sides of the paper P (S20: YES), the process proceeds to step S21.

  In step S21, the data is set so that the flushing dot area moves toward the downstream side in the forward transport direction until the flushing dot areas are not adjacent to each other or until the flushing dot areas do not overlap on both sides of the paper P. Data in the storage unit 37a is changed. Here, as shown in FIG. 7B, there is another flushing dot area diagonally to the upper right of the flushing dot area moved in step S18, and these are adjacent to each other. Therefore, as shown in FIG. 7C, this flushing dot area is further moved downstream by 3 dot areas in the forward transport direction so as not to be adjacent to other flushing dot areas.

On the other hand, when the flushing dot areas do not overlap on both sides of the paper P (S20: NO), the non-ejection time during which ink is not ejected based on the data of all the flushing dot areas stored in the data storage unit 37a. It is determined whether or not there is an ejection port 108 that has a predetermined time or longer (step S22). In this embodiment, instead of determining whether or not there is an ejection port 108 in which the non-ejection time during which ink is not ejected is a predetermined time or longer, the flushing dot interval in the forward transport direction is equal to or greater than the predetermined dot interval. It is determined whether or not the discharge port 108 exists. If there is an ejection port 108 whose non-ejection time is equal to or longer than the predetermined time (S22: YES), the data in the data storage unit 37a is changed so that a new flushing dot area is added, and the non-ejection time is predetermined. It is made for the discharge port 108 which becomes more than time not to exist (step S23).

  As shown in FIG. 7C, the flushing dot area moved in step S18 and step S21 has an interval between the flushing dot area located upstream in the forward conveyance direction of the flushing dot area and a predetermined dot interval. That's it. That is, the non-ejection time of the ejection port 108 that ejects ink that lands on the flushing dot region is equal to or longer than a predetermined time. Therefore, by adding a dot area (black dot area in the figure) separated from the flushing dot area to the upstream side in the forward transport direction by a predetermined dot interval as a new flushing dot area, the non-ejection time is longer than the predetermined time. Thus, there can be no discharge port 108.

  When there is no ejection port 108 whose non-ejection time is equal to or longer than the predetermined time (S22: NO), the processes of steps S12 to S21 are performed on the data of all the flushing dot areas stored in the data storage unit 37a. It is determined whether or not (step S24). If there is data that has not yet been processed in steps S12 to S21 (S24: NO), the process returns to step S12 described above. On the other hand, when all the data has been processed (S24: YES), the data stored in the data storage unit 37a is confirmed.

  As described above, in the inkjet printer 101 of the present embodiment, among a plurality of dot areas, at least one dot area from the edge dot area corresponding to the edge of the image related to the image data stored in the image data storage unit 32. No flushing dots are formed in the exclusion range. Therefore, it is possible to prevent the flashing dots from being formed in the vicinity of the edge of the image, and to suppress the perception of the flushing dot as a part of the image edge and the disturbance of the image edge. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control.

  Further, in the ink jet printer 101 of the present embodiment, whether the ink that has landed on the paper P is likely to bleed, whether the line of the image is thin, or the lightness of the flushing dot is the most in the dot area where the flushing dot is formed. All conditions are met based on the four conditions of whether the brightness of the image dots formed in the edge dot area located in the vicinity is large and whether the amount of the treatment liquid that lands on the edge dot area is large. If not, the exclusion range is determined to be a first area within one dot area from the edge dot area. If at least one of the conditions is met, the exclusion area is a second area within two dot areas from the edge dot area. A range determining unit 37d for determining the range is provided. Therefore, the exclusion range can be appropriately determined according to the content of the image, printing conditions, and the like. That is, when the image edge is easily disturbed, when it is important to maintain high visibility of the image edge, or when the flushing dots are easily noticeable, the exclusion range can be set wide.

  In the inkjet printer 101 of the present embodiment, the range determination unit 37d distributes the error of the image data corresponding to the edge dot region when the print data generation unit 33 generates the print data from the image data by the error diffusion method. This range is defined as the first area of the exclusion range. Accordingly, it is possible to prevent the flushing dots formed in the vicinity of the edge dot region from conspicuously overlapping with the image dots formed by error diffusion.

Further, in the ink jet printer 101 of the present embodiment, when there are flushing dot areas stored in the data storage unit 37a that exist within the exclusion range, the ejection port 108 that ejects ink to the dot area is not suitable. The data in the data storage unit 37a is changed so that the discharge time is shorter than before the change. Therefore, the non-ejection time of the ejection port 108 can be kept shorter than the predetermined time, and the visibility of the image edge can be improved while ensuring the ejection performance. At this time, the data in the data storage unit 37a is changed so that there is no ejection port 108 whose non-ejection time is equal to or longer than a predetermined time for the data of other flushing dot regions stored in the data storage unit 37a. . Therefore, when the non-ejection time of the ejection port 108 is changed to be short, a portion where the non-ejection time becomes longer occurs in other data, and it is possible to prevent the ejection performance from deteriorating.

  In addition, in the inkjet printer 101 of the present embodiment, when there are flushing dot areas stored in the data storage unit 37a that are adjacent to each other, any of these flushing dot areas is different from other flushing dot areas. The data in the data storage unit 37a is changed so as to move to a position that is not adjacent. Therefore, it is possible to prevent the flushing dots from being contiguous and adjacent.

  Furthermore, in the inkjet printer 101 of the present embodiment, when performing double-sided printing, if there are flushing dot areas stored in the data storage unit 37a that overlap on both sides of the paper P, these flushing dot areas The data in the data storage unit 37a is changed so that any one of them moves to a position that does not overlap with the other flushing dot areas. Therefore, it is possible to prevent the flushing dots from conspicuous by overlapping on both sides of the paper P.

  In the ink jet printer 101 of the present embodiment, the recording head 1a is a line-type head that extends in the main scanning direction orthogonal to the transport direction and is fixedly provided. In the case of a line-type head that is fixedly provided, it is particularly necessary to eject ink onto the paper P during flushing. Therefore, the application of the present invention is useful for the inkjet printer 101 of the present embodiment.

  The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and various design changes can be made as long as they are described in the claims. Is.

  For example, in the above-described embodiment, when the exclusion range is determined by the range determination unit 37d, four conditions are determined in order, and if all the conditions are not satisfied, the exclusion range is set as the first region, and at least one Although the case where the exclusion range is determined as the second region when the condition is satisfied has been described, the processing in the range determination unit 37d is not limited to this. Here, a modified example of the processing in the range determination unit 37d will be described with reference to FIG. First, in step S112, it is determined whether the ink attached to the paper P is likely to bleed as the first condition. If it is determined that the ink is likely to bleed (S112: YES), the susceptibility to bleeding such as the type of the paper P or the like. Is stored (S113). Next, in step S114, it is determined whether the line of the image is thin as a second condition. If it is determined that the line is thin (S114: YES), the thin line flag is turned ON (S115). Subsequently, in step S116, as a third condition, it is determined whether the brightness of the image dots formed in the edge dot region is larger than the brightness of the flushing dots, and when it is determined that the brightness of the image dots is large (S116). : YES), the brightness difference between them is stored (S117). Finally, in step S118, as a fourth condition, it is determined whether or not the amount of the processing liquid that lands on the edge dot region is large. If it is determined that the amount of the processing liquid is large (S118: YES), the processing is performed. The amount of liquid is stored (S119). In step S120, an optimal exclusion range is determined based on the contents stored in steps S113, S115, S117, and S119 described above, and it is determined whether or not the flushing dot is located within the exclusion range. That is, considering the conditions of ease of bleeding, whether or not it is a fine line, the magnitude of the brightness difference, and the amount of processing liquid, the range is set to a range that matches the conditions that need to determine the widest exclusion range. The other steps in FIG. 9 are the same as the steps described in the above-described embodiment, and thus the description thereof is omitted.

  In the above-described embodiment, as a control unit that controls each actuator included in the actuator unit 21 provided in each recording head 1a, image recording is performed based on print data stored in the print data storage unit 34. Although the case where the control unit 35 and the flushing control unit 36 that performs control based on the flushing data created by the flushing data creation unit 37 is described has been described, the present invention is not limited to this. That is, one control unit may perform control based on ejection data obtained by combining print data and flushing data.

  Further, in the above-described embodiment, the precoat data creating unit 41 lands the treatment liquid on the dot region where ink is landed based on the control of the image recording control unit 35 among the plurality of dot regions defined on the paper P. The case where data is created as described above has been described, but the processing liquid may also land on the dot area around the dot area on which the ink lands based on the control of the image recording control unit 35. In this case, the fourth condition for determining the exclusion range in the range determination unit 37d is that the range adjacent to the edge dot region and where the treatment liquid lands is wide.

  Furthermore, although the above-mentioned embodiment demonstrated the case where the range determination part 37d which determines an exclusion range was provided, the range determination part 37d does not need to be. In this case, the exclusion range is fixedly defined as a range from the edge dot region to one dot region or more.

  In the above-described embodiment, the range determination unit 37d distributes the error of the image data corresponding to the edge dot region when the print data generation unit 33 generates the print data from the image data by the error diffusion method. However, the present invention is not limited to this. That is, the exclusion range may be determined regardless of the range in which the error is distributed.

  Furthermore, in the above-described embodiment, a case has been described in which the print data generation unit 33 generates print data from image data by the error diffusion method, but the print data generation method is not limited to this.

  In the above-described embodiment, the case where the initial data creation unit 37b creates the flushing data so that the flushing dots are formed on the paper P at a predetermined dot interval irrespective of the image data has been described. It is not limited to. That is, for example, based on the ink discharge interval from each discharge port 108 of the recording head 1a under the control of the image recording control unit 35, the discharge port 108 whose ink discharge interval is equal to or longer than a predetermined time is searched for, and the ink discharge interval is a predetermined time Alternatively, the flushing data may be generated so that the flushing dots are formed by ejecting the ink from the ejection port 108 so as to be shorter.

  In the above-described embodiment, when there is a flushing dot area that exists within the exclusion range, the case where the flushing dot area is moved to the downstream side in the forward conveyance direction to the outside of the exclusion range has been described, but the present invention is not limited to this. . For example, the paper P is divided into a plurality of blocks composed of a plurality of dot areas, and the total amount of ink ejected from each recording head 1a and landing on the paper P is calculated for each block based on the control of the image recording control unit 35. Keep it. When the flushing dot area is moved, the flushing dot is placed on a block that is located downstream of the block in which the flushing dot area is located in the forward transport direction and has a small total amount of ink that lands in the block. The area may be moved.

  In addition, in the above-described embodiment, the case where the double-sided printing mechanism 24 that reverses the front and back of the paper P in order to record images on both sides of the paper P has been described, but the double-sided printing mechanism 24 may be omitted. .

  In the above-described embodiment, the line type printer including the head 1 extending in the main scanning direction has been described. However, the present invention is applied to a serial type printer including a head movable in the main scanning direction. You can also

  Further, in the above-described embodiment, as shown in FIG. 7C, a dot area (a black dot area in the figure) separated by a predetermined dot interval from the moved flushing dot area to the upstream side in the forward conveyance direction. Although it is added as a new flushing dot area, it is not added, but the flushing dot area adjacent to the upstream side in the forward transport direction of the moved flushing dot area is set at a predetermined distance from the moved flushing dot area. You may perform the process moved to the forward conveyance direction downstream side so that it may become a space | interval.

  Further, in the above-described embodiment, the actuator unit 21 is disclosed as means for imparting discharge energy, and a specific example of the actuator unit includes a unimorph type piezoelectric actuator. However, as a means for imparting ejection energy, another means for imparting thermal-type ejection energy that heats the liquid ink in the nozzle with a heating element, generates bubbles, and pushes the ink from the nozzle for printing is applied. You can also.

1a Recording head (first discharge head)
1b Treatment liquid discharge head (second discharge head)
16 Transport mechanism 21 Actuator unit 24 Duplex printing mechanism 32 Image data storage unit (image data storage means)
35 Image recording control unit (image recording control means)
36 Flushing control unit (flushing control means)
37 Flushing data creation unit (preliminary discharge data creation means)
37b Initial data creation unit (initial data creation means)
37c Change part (change means)
37d Range determination unit (range determination means)
40 Precoat control unit (second liquid control means)
41 Precoat data creation unit (second liquid discharge data creation means)
108 Discharge port (first discharge port, second discharge port)

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. a first head having a first energy application device which applies an ejection energy for ejecting liquid, corresponding to the previous type recording resolution of the first distance to the conveying direction corresponding to the direction orthogonal to the recording resolution perpendicular to the conveying direction a print data storage unit for storing print data for ejecting the first liquid to the plurality of dot regions defined by sectioning on a recording medium by the second distance, the print data stored in the print data storage unit the image recording control means for controlling said first energy application device of the first head, among the plurality of dot regions, the print data stored in the print data storage unit based on Preliminary discharge data for preliminary discharge of the first liquid is prepared so that the first liquid lands at a position separated by at least one dot area or more from the edge dot area which is a dot area corresponding to the edge of the image. The first energy application unit of the first ejection head is configured to form ejection data on the recording medium based on the ejection data creation unit and the preliminary ejection data of the first liquid created by the preliminary ejection data creation unit. Flashing control means for controlling. Further, the image forming apparatus further includes range determining means for determining the predetermined range, and creates the preliminary ejection data based on the predetermined range determined by the range determining means, the range determining means corresponding to the edge dot region The predetermined range is determined such that the smaller the line of the image including the data to be processed, the wider the predetermined range.

According to the above-described configuration, it is possible to prevent the flushing dot from being perceived as a part of the image edge and disturbing the image edge by preventing the flushing dot from being formed in the vicinity of the edge of the image. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control. In addition, the predetermined range can be appropriately determined according to the content of the image, printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved. Furthermore, the visibility of the image edge can be improved reliably when the image is a relatively thin line and it is important to maintain the visibility of the image edge high.

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. A first ejection head having first energy application means for applying ejection energy for ejecting liquid; a first distance corresponding to a recording resolution in an orthogonal direction orthogonal to the transport direction; and a first distance corresponding to a recording resolution in the transport direction. A print data storage unit for storing print data for discharging the first liquid in a plurality of dot areas defined on the recording medium at two distances; and the print data stored in the print data storage unit Image recording control means for controlling the first energy application means of the first ejection head based on the print data stored in the print data storage section among the plurality of dot areas Preliminary discharge data for preliminary discharge of the first liquid is prepared so that the first liquid lands at a position separated by at least one dot area or more from the edge dot area which is a dot area corresponding to the edge of the image. The first energy application unit of the first ejection head is configured to form ejection data on the recording medium based on the ejection data creation unit and the preliminary ejection data of the first liquid created by the preliminary ejection data creation unit. Flashing control means for controlling. Further, the image forming apparatus further comprises range determining means for determining the predetermined range, and creates the preliminary ejection data based on the predetermined range determined by the range determining means, wherein the range determining means determines the brightness of the flushing dot. In comparison, the predetermined range is determined such that the larger the brightness of the image dot formed in the edge dot region located closest to the dot region where the flushing dot is formed, the wider the predetermined range. According to this configuration, by preventing the flushing dots from being formed in the vicinity of the edge of the image, it is possible to suppress the perception of the flushing dot as a part of the image edge and the disturbance of the image edge. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control. In addition, the predetermined range can be appropriately determined according to the content of the image, printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved. Furthermore, even if the brightness of the image dots formed in the edge dot area is larger than the brightness of the flushing dots and the flushing dots are easily noticeable, the flashing dots are formed away from the edge dot area to make it less noticeable. Can do.

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. A first ejection head having first energy application means for applying ejection energy for ejecting liquid; a first distance corresponding to a recording resolution in an orthogonal direction orthogonal to the transport direction; and a first distance corresponding to a recording resolution in the transport direction. A print data storage unit for storing print data for discharging the first liquid in a plurality of dot areas defined on the recording medium at two distances; and the print data stored in the print data storage unit Image recording control means for controlling the first energy application means of the first ejection head based on the print data stored in the print data storage section among the plurality of dot areas Preliminary discharge data for preliminary discharge of the first liquid is prepared so that the first liquid lands at a position separated by at least one dot area or more from the edge dot area which is a dot area corresponding to the edge of the image. The first energy application unit of the first ejection head is configured to form ejection data on the recording medium based on the ejection data creation unit and the preliminary ejection data of the first liquid created by the preliminary ejection data creation unit. Flashing control means for controlling. A range determining means for determining the predetermined range; a second discharge port that discharges a second liquid that is a liquid discharged onto the recording medium and promotes fixing of the first liquid onto the recording medium; and A second liquid having second discharge energy applying means for applying discharge energy for discharging the second liquid from the second discharge port; and a second liquid for generating discharge data of the second liquid based on the print data Discharge data creating means; and second liquid control means for controlling the second ejection energy applying means of the second ejection head based on the ejection data created by the second liquid ejection data creating means. Generating the preliminary ejection data based on the predetermined range determined by the range determining means, wherein the range determining means controls the edge dot under the control of the second liquid control means. The more the amount of the second liquid landing on frequency, determines the predetermined range as the predetermined range becomes wider. According to this configuration, by preventing the flushing dots from being formed in the vicinity of the edge of the image, it is possible to suppress the perception of the flushing dot as a part of the image edge and the disturbance of the image edge. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control. In addition, the predetermined range can be appropriately determined according to the content of the image, printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved. Further, the second liquid acts on the area where the flushing dots are formed on the recording medium, the fixing of the flushing dots is promoted, and the flushing dots can be prevented from being noticeable.

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. A first ejection head having first energy application means for applying ejection energy for ejecting liquid; a first distance corresponding to a recording resolution in an orthogonal direction orthogonal to the transport direction; and a first distance corresponding to a recording resolution in the transport direction. A print data storage unit for storing print data for discharging the first liquid in a plurality of dot areas defined on the recording medium at two distances; and the print data stored in the print data storage unit Image recording control means for controlling the first energy application means of the first ejection head based on the print data stored in the print data storage section among the plurality of dot areas Preliminary discharge data for preliminary discharge of the first liquid is prepared so that the first liquid lands at a position separated by at least one dot area or more from the edge dot area which is a dot area corresponding to the edge of the image. The first energy application unit of the first ejection head is configured to form ejection data on the recording medium based on the ejection data creation unit and the preliminary ejection data of the first liquid created by the preliminary ejection data creation unit. Flashing control means for controlling. A range determining means for determining the predetermined range; a second discharge port that discharges a second liquid that is a liquid discharged onto the recording medium and promotes fixing of the first liquid onto the recording medium; and A second liquid having second discharge energy applying means for applying discharge energy for discharging the second liquid from the second discharge port; and a second liquid for generating discharge data of the second liquid based on the print data Discharge data creating means; and second liquid control means for controlling the second ejection energy applying means of the second ejection head based on the ejection data created by the second liquid ejection data creating means. Generating the preliminary ejection data based on the predetermined range determined by the range determining means, wherein the range determining means is adjacent to the edge dot region and the second liquid control means. As the area in which the second liquid is landed discharged by the control on a wide, it determines the predetermined range as the predetermined range becomes wider. According to this configuration, by preventing the flushing dots from being formed in the vicinity of the edge of the image, it is possible to suppress the perception of the flushing dot as a part of the image edge and the disturbance of the image edge. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control. In addition, the predetermined range can be appropriately determined according to the content of the image, printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved. Further, the second liquid that has landed in the vicinity of the edge dot region promotes the fixing of the flushing dots and prevents the flushing dots from being noticeable.

The liquid ejection apparatus of the present invention includes a transport mechanism that transports a recording medium in a transport direction, a first discharge port that discharges a first liquid for forming an image on the recording medium, and a first through the first discharge port. A first ejection head having a first energy application unit that applies ejection energy for ejecting liquid, and data obtained by converting image data input from the outside, corresponding to a recording resolution in an orthogonal direction orthogonal to the transport direction. Print data storage means for storing print data for ejecting the first liquid in a plurality of dot areas defined on the recording medium by the first distance and the second distance corresponding to the recording resolution in the transport direction And image recording control means for controlling the first energy application means of the first ejection head based on the image data stored in the image data storage means, and the plurality of dot regions Of these, the first liquid is landed at a position separated from the edge dot area, which is the dot area corresponding to the edge of the image related to the image data stored in the image data storage means, by at least one dot area or more. Preliminary ejection data creation means for creating preliminary ejection data for preliminary ejection of the first liquid, and flushing dots are formed on the recording medium based on the preliminary ejection data for the first liquid created by the preliminary ejection data creation means. And a flushing control means for controlling the first energy application means of the first discharge head. The preliminary ejection data creation means further includes range determination means for determining the predetermined range, creates the preliminary ejection data based on the predetermined range determined by the range determination means, and performs the image recording control. The unit controls the first ejection energy applying unit of the first ejection head based on the print data obtained by converting the image data by an error diffusion method, and the range determination unit is configured to correspond to the edge dot region. The range in which the error of the image data is distributed is determined as the predetermined range. According to this configuration, by preventing the flushing dots from being formed in the vicinity of the edge of the image, it is possible to suppress the perception of the flushing dot as a part of the image edge and the disturbance of the image edge. Therefore, it is possible to improve the visibility of the image edge without requiring complicated control. In addition, the predetermined range can be appropriately determined according to the content of the image, printing conditions, and the like. Therefore, the visibility of the image edge can be reliably improved. Further, it is possible to prevent the flushing dots formed in the vicinity of the edge dot region from being conspicuously overlapped with the image dots formed by error diffusion.

Claims (13)

A transport mechanism for transporting the recording medium in the transport direction;
A first discharge head having a first discharge port for discharging a first liquid for forming an image on a recording medium, and a first energy applying unit for applying discharge energy for discharging the first liquid from the first discharge port. When,
The image data input from the outside is defined on the recording medium by dividing it into a first distance corresponding to the recording resolution in the orthogonal direction orthogonal to the transport direction and a second distance corresponding to the recording resolution in the transport direction. Image data storage means for storing data for discharging the first liquid in a plurality of dot areas;
Image recording control means for controlling the first energy application means of the first ejection head based on the image data stored in the image data storage means;
Of the plurality of dot areas, the first is located at a position away from a predetermined range of at least one dot area from an edge dot area that is a dot area corresponding to an edge of an image related to image data stored in the image data storage means. Preliminary ejection data creating means for creating preliminary ejection data for preliminary ejection of the first liquid so that the liquid lands,
Flushing control means for controlling the first energy application means of the first ejection head so that flushing dots are formed on the recording medium based on the preliminary ejection data of the first liquid created by the preliminary ejection data creation means; A liquid ejecting apparatus comprising:   The preliminary ejection data creation unit further includes a range determination unit that determines the predetermined range, and creates the preliminary ejection data based on the predetermined range determined by the range determination unit. The liquid discharge apparatus according to 1.   The liquid ejection apparatus according to claim 2, wherein the range determination unit determines the predetermined range such that the predetermined range becomes wider as the first liquid landed on the recording medium is more likely to spread. The image recording control unit controls the first ejection energy applying unit of the first ejection head based on conversion data obtained by converting the image data by an error diffusion method;
The liquid ejecting apparatus according to claim 2, wherein the range determining unit determines a range in which an error of the image data corresponding to the edge dot region is distributed as the predetermined range.   The range determination unit determines the predetermined range so that the predetermined range becomes wider as a line of an image including data corresponding to the edge dot region is thinner. The liquid ejection device according to item.   The range determining means determines that the predetermined range is greater as the brightness of the image dots formed in the edge dot area located closest to the dot area where the flushing dots are formed is larger than the brightness of the flushing dots. The liquid ejecting apparatus according to claim 2, wherein the predetermined range is determined to be wide. A liquid ejected onto the recording medium, a second ejection port that ejects a second liquid that promotes fixing of the first liquid to the recording medium, and an ejection that ejects the second liquid from the second ejection port A second ejection head having second ejection energy application means for applying energy;
Second liquid discharge data creating means for creating discharge data of the second liquid based on the image data stored in the image data storage means;
A second liquid control means for controlling the second discharge energy applying means of the second discharge head based on the discharge data created by the second liquid discharge data creating means;
The range determination means determines the predetermined range such that the larger the amount of the second liquid that is landed on the edge dot region is, the wider the predetermined range is under the control of the second liquid control means. Item 7. The liquid ejection device according to any one of Items 2 to 6. A liquid ejected onto the recording medium, a second ejection port that ejects a second liquid that promotes fixing of the first liquid to the recording medium, and an ejection that ejects the second liquid from the second ejection port A second ejection head having second ejection energy application means for applying energy;
Second liquid discharge data creating means for creating discharge data of the second liquid based on the image data stored in the image data storage means;
A second liquid control means for controlling the second discharge energy applying means of the second discharge head based on the discharge data created by the second liquid discharge data creating means;
The range determining unit determines the predetermined range so that the larger the range in which the second liquid that is ejected by the control of the second liquid control unit is adjacent to the edge dot region is wider. The liquid ejection apparatus according to claim 2, wherein the liquid ejection apparatus is a liquid ejection apparatus. The preliminary ejection data creation means includes
Initial data creation means for creating initial preliminary ejection data of the first liquid so that the first ejection port in which the non-ejection time during which the first liquid is not ejected is a predetermined time or longer does not exist;
When the first liquid ejected based on the initial preliminary ejection data created by the initial data creating means lands within the predetermined range, the first ejection port from which the first liquid is ejected. The liquid ejecting apparatus according to claim 1, further comprising a changing unit that changes the preliminary preliminary ejection data so that the non-ejection time is shorter than before the change. .   When the preliminary discharge data is changed so that the non-ejection time of the first discharge port is shorter than before the change, the changing unit is configured to change the first liquid for data other than the preliminary discharge data to be changed. The liquid ejection apparatus according to claim 9, wherein the data is changed so that the first ejection port in which a non-ejection time during which ejection is not performed is a predetermined time or longer does not exist.   11. The liquid ejection apparatus according to claim 1, wherein the preliminary ejection data creating unit creates preliminary ejection data so that dot regions where flushing dots are formed are not adjacent to each other. A double-sided printing mechanism for recording images on both sides of the recording medium;
2. The preliminary ejection data creation means creates preliminary ejection data for the first liquid so that dot areas landed by the first liquid ejected by preliminary ejection do not overlap on both sides of the recording medium. The liquid discharge apparatus of any one of -11.   The liquid ejection apparatus according to claim 1, wherein the first ejection head is a line-type head that extends in the orthogonal direction and is fixedly provided.

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