Printing method, printing apparatus, and program

Abstract

To suitably reduce an influence of a defective nozzle.SOLUTION: A printing method for printing by using a printer 10 includes a condition setting stage for setting a printing condition, a condition confirmation stage for checking the printing condition, and a printing execution stage, in which the printer 10, on the basis of a setting path number set by an integral value of 1 or more, executes a main scan operation and enables the execution of a path modulation operation which increases the number of the main scan operation performed on at least part of a medium above the set path number, and a path modulation degree setting in the condition setting stage. The condition confirmation stage includes a defective nozzle confirmation stage, a recovery confirmation stage for confirming whether or not nozzle recovery is possible and a condition retrieval stage, which is a stage for retrieving a new printing condition when nozzle recovery is impossible and retrieves a printing condition which enables nozzle recovery by varying the path modulation degree.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a printing method, a printing apparatus, and a program.

Background Art

[0002] Conventionally, an inkjet printer, which is a printing apparatus that performs printing by an inkjet method, has been widely used. Also, regarding the case where there is a defective nozzle in the inkjet head of an inkjet printer, a method for reducing the influence of the defective nozzle is known (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to reduce the influence of a defective nozzle, for example, instead of a defective nozzle, ink is ejected by another nozzle (hereinafter referred to as a substitute nozzle) at the ink ejection position where ink should originally be ejected by an unnecessary nozzle. However, in this case, if, for example, the substitute nozzle is also a defective nozzle, the influence of the defective nozzle cannot be appropriately reduced, and printing with desired quality may not be possible. Therefore, conventionally, it has been desired to more appropriately reduce the influence of a defective nozzle. Thus, an object of the present invention is to provide a printing method, a printing apparatus, and a program that can solve the above problems.

Means for Solving the Problems

[0005] In the nozzle recovery method, which uses an alternative nozzle to eject ink in place of a faulty nozzle, the available alternative nozzles change depending on printing conditions such as print resolution and number of passes. Therefore, even if the alternative nozzle is also a faulty nozzle under certain printing conditions, changing the printing conditions may allow a normal nozzle to be selected as the alternative nozzle. However, changing printing conditions such as print resolution and number of passes may significantly alter print quality and printing speed.

[0006] More specifically, print resolution is a printing condition that has a very significant impact on print quality. Therefore, changing the print resolution will result in a large change in print quality. For example, increasing the print resolution to prevent a decrease in print quality may drastically reduce the printing speed. Furthermore, changing the print resolution may require recreating the print data (job) supplied to the printing device. In this case, significant rework will occur in the print production process. In addition, the number of passes is usually selected from several integer values ​​that are pre-configured according to the printing device's configuration. Therefore, changing the number of passes usually results in a large, discontinuous change in print quality. Thus, even when changing the number of passes, it can be considered that the change in print quality caused by changing the alternative nozzle will be excessively large. In this case, increasing the number of passes to prevent a decrease in print quality may drastically reduce the printing speed.

[0007] Furthermore, to mitigate the impact of defective nozzles, one could consider using a function in the printing device to select the inkjet head to use for printing, such as printing only with inkjet heads that do not contain the defective nozzle. However, in this case, the printing speed may decrease significantly due to the reduced number of inkjet heads used. Depending on the configuration of the printing device, it may also be necessary to recreate the print data. Another possible countermeasure for defective nozzles is to replace the inkjet head containing the defective nozzle. However, this would require work to replace the head and production may be temporarily suspended while waiting for service from the printing device manufacturer.

[0008] In response to this, the inventors of the present invention have found that the effects of a faulty nozzle can be more effectively reduced by utilizing the characteristics of path modulation operation, such as the MAPS (Mimaki Advanced Pass System) function used in printing equipment manufactured by Mimaki Engineering Co., Ltd. In this case, the path modulation operation can be considered as, for example, an operation in which the main scanning operation is performed based on a number of passes set to an integer value of 1 or more (set number of passes), and the number of times the main scanning operation is performed on at least a part of the printing medium is greater than the set number of passes. In this case, for example, it becomes possible to change the nozzle used as a replacement nozzle without changing the set number of passes or the resolution. Furthermore, this makes it possible to appropriately reduce the effects of a faulty nozzle by using new printing conditions that enable nozzle recovery, while appropriately preventing large changes in print quality or a significant decrease in printing speed, even when the nozzle that becomes the replacement nozzle under the initial printing conditions is a faulty nozzle.

[0009] Furthermore, the inventors of this invention, through further diligent research, have discovered the features necessary to obtain such effects, leading to the present invention. In order to solve the above problems, the present invention provides a printing method for printing using a printing apparatus, comprising: a data acquisition step of acquiring print data indicating an image to be printed; a condition setting step of setting print conditions which are the conditions for printing to be performed by the printing apparatus; a condition confirmation step of confirming the print conditions set in the condition setting step; and a print execution step of causing the printing apparatus to perform a printing operation based on the print data, wherein the printing apparatus comprises an inkjet head having a nozzle row in which a plurality of nozzles are arranged, and prints on the medium by causing the inkjet head to perform a main scanning operation in which it moves relative to the medium to be printed in a predetermined main scanning direction and ejects ink, and a sub-scanning operation in which it moves relative to the medium in a sub-scanning direction perpendicular to the main scanning direction, and executes the main scanning operation based on a set number of passes which is a number set to be an integer value of 1 or more, and prints on at least a part of the medium The system is capable of performing a path modulation operation that increases the number of times the main scanning operation is performed to a number greater than the set number of passes, and in the condition setting step, at least a path modulation degree is set as the printing condition, which indicates the degree of modulation that changes the number of times the main scanning operation is performed on at least a part of the medium in the path modulation operation, and the condition confirmation step includes a defective nozzle confirmation step that confirms whether or not a defective nozzle, which is the nozzle with poor ejection characteristics, is present in the nozzle row of the inkjet head, a recovery confirmation step that confirms whether or not nozzle recovery is possible using a nozzle different from the defective nozzle if a defective nozzle is present, and a new printing condition that is the new printing condition if a defective nozzle is present and nozzle recovery is not possible, and a condition search step that searches for a printing condition in which nozzle recovery becomes possible by changing the path modulation degree.

[0010] With this configuration, for example, by changing the path modulation degree during the condition search phase, it is possible to appropriately change the nozzles that can be used as replacement nozzles for defective nozzles. Furthermore, this allows for the appropriate search for new printing conditions that enable nozzle recovery, even if nozzle recovery is not possible with the initial printing conditions set during the condition setting phase. Moreover, in this case, by changing the path modulation degree, it becomes possible to use conditions that do not change the number of set passes or the print resolution as new printing conditions that enable nozzle recovery. Furthermore, this allows for the appropriate reduction of the impact of defective nozzles while appropriately preventing large changes in print quality or significant decreases in print speed. In the condition search phase, it is preferable to change the path modulation degree in a direction that improves print quality. With this configuration, for example, it is possible to appropriately search for new printing conditions while maintaining the print quality desired by the user. Depending on the conditions requested by the user, the direction of change in the path modulation degree may also be considered, for example, in a direction that decreases the print speed.

[0011] In this configuration, the number of main scanning operations performed on each position of the media can be considered, for example, the number of times the inkjet head passes over the position opposite to the media position. Furthermore, when the pass modulation degree is changed in the pass modulation operation, the area on the media where, for example, more main scanning operations are performed than the set number of passes changes. In this case, it can also be considered that the average number of main scanning operations changes. Therefore, the pass modulation degree can be considered, for example, a parameter associated with the average number of main scanning operations. In this case, the average number of main scanning operations can be considered to change in decimal units based on, for example, the set number of passes specified as an integer value and the pass modulation degree. In this case, in the pass modulation operation, for example, the average number of main scanning operations can be changed based on the pass modulation degree within a range of more than or equal to the set number of passes and less than or equal to twice the set number of passes. With this configuration, for example, the pass modulation operation can be performed appropriately. Furthermore, by changing the pass modulation degree within this range, it is possible to appropriately search for new printing conditions that enable nozzle recovery.

[0012] Furthermore, in this configuration, the path modulation index is a parameter that corresponds to a value of 100% when the main scanning operation is performed for a set number of passes over the entire medium, and to a value of 50% when the main scanning operation is performed for twice the set number of passes over the entire medium. In this case, during the condition search phase, for example, the path modulation index is changed in increments of 2% or less from the value corresponding to 100% to search for printing conditions that enable nozzle recovery. With this configuration, for example, the path modulation index can be appropriately changed in increments that do not abruptly change the print quality or printing speed. The increment for changing the path modulation index may be, for example, around 0.5 to 2%. It is preferable to set this increment to, for example, around 1%. Furthermore, during the condition search phase, it is conceivable to change the path modulation index within a range that is, for example, less than or equal to the value corresponding to 100% and greater than or equal to the value corresponding to 50%. With this configuration, for example, the conditions for the path modulation operation can be appropriately changed. In addition, this makes it possible to appropriately search for new printing conditions that enable nozzle recovery.

[0013] Furthermore, in this configuration, during the condition setting stage, for example, the sub-scanning movement amount is set according to the path modulation degree. In this case, the sub-scanning movement amount can be considered as, for example, the amount by which the inkjet head moves relative to the medium in a single sub-scan operation. Also, in this case, during the condition search stage, for example, by changing the path modulation degree, the sub-scanning movement amount corresponding to the path modulation degree is changed to search for printing conditions that enable nozzle recovery. With this configuration, for example, it is possible to appropriately search for new printing conditions that enable nozzle recovery.

[0014] Furthermore, if new printing conditions that enable nozzle recovery are found during the condition search phase, the user may be given the option to choose whether or not to adopt the new printing conditions. In this case, the user could choose to either print using the new printing conditions or print without using the new printing conditions and without performing nozzle recovery. Then, during the print execution phase, the printing device is instructed to perform the printing operation based on the print data, based on the user's selection received during the condition search phase. With this configuration, for example, printing can be performed appropriately with printing conditions that match the user's preferences.

[0015] Furthermore, in this case, it is conceivable that, under certain conditions, the system may automatically adopt new printing conditions without requiring user selection. More specifically, for example, if new printing conditions that enable nozzle recovery are found during the condition search phase, the system further determines whether the new printing conditions match any pre-registered conditions. If they match, the system allows the printing device to execute the printing operation based on the print data using the new printing conditions during the print execution phase, without requiring the user to choose whether or not to print using the new printing conditions. This configuration allows for more efficient execution of printing operations with new printing conditions. In addition, whether or not to continue such automatic printing operations may be switched depending on the operating mode set for the printing device. In this case, for example, when a predetermined operating mode is selected, the system automatically adopts the new printing conditions as described above. Depending on the configuration of the printing device, for example, in a predetermined operating mode, the system may always automatically adopt new printing conditions without requiring user selection.

[0016] Furthermore, depending on the required print quality and purpose, it may be necessary to use stricter criteria to judge changes in print quality or decreases in print speed resulting from changes in printing conditions. Also, even if new printing conditions that enable nozzle recovery are found, it may be desirable to stop (cancel) the printing operation rather than adopting the new printing conditions. For this reason, during the condition search phase, it may be possible to determine whether the new printing conditions match, for example, the print cancellation conditions that have been registered as conditions under which printing should be stopped. If they do match, for example, the printing operation may be stopped. With this configuration, for example, the printing operation can be appropriately stopped under predetermined conditions. As print cancellation conditions, for example, conditions that correspond to changes in print quality beyond a predetermined tolerance range or increases in printing time beyond a predetermined percentage, depending on the print quality and printing speed desired by the user, can be registered.

[0017] Furthermore, depending on the purpose of printing, other conditions besides the pass modulation degree may be further varied during the condition search phase to search for new printing conditions. More specifically, during the condition search phase, for example, the number of set passes and the main scan speed may be further varied to search for printing conditions that enable nozzle recovery. In this case, the main scan speed can be considered as, for example, the speed at which the inkjet head moves relative to the medium during the main scan operation (scan speed). With this configuration, for example, printing conditions that enable nozzle recovery can be searched from a larger number of conditions. In addition, this makes it possible to appropriately search for new printing conditions that are more preferable depending on the purpose of printing, for example. In this case, as new printing conditions, for example, conditions that allow printing to continue with the least decrease in printing speed may be searched for.

[0018] Furthermore, instead of automatically changing the number of set passes or the main scan speed, it is conceivable to prompt the user to make changes, for example, through a dialog box. In this case, under certain conditions, for example, during the condition search phase, the user could be prompted to change the number of set passes. Similarly, under certain conditions, for example, during the condition search phase, the user could be prompted to change the main scan speed. With this configuration, for example, it becomes possible to search for printing conditions that enable nozzle recovery from a wider range of conditions as needed. In this case, the predetermined conditions could include, for example, conditions that correspond to situations where no new conditions are found or where the print speed decreases significantly under new conditions.

[0019] Furthermore, the features of the present invention can also be considered by focusing on the sub-scanning movement amount, for example. In this case, during the condition search stage, printing conditions that enable nozzle recovery are searched for by changing the sub-scanning movement amount, for example. Even with this configuration, new printing conditions that enable nozzle recovery can be appropriately searched for. In this case as well, the printing device performs the main scanning operation based on the number of set passes, which is set to an integer value of 1 or more. If the pass width is defined as the value obtained by dividing the nozzle row length, which is the width of the nozzle row in the sub-scanning direction, by the number of set passes, then during the condition search stage, the sub-scanning movement amount is changed within a range of 0.5 times or more and 1 time less than or equal to the pass width. With this configuration, new printing conditions that enable nozzle recovery can be searched for more appropriately. In addition, the influence of defective nozzles can be appropriately reduced. Furthermore, as a configuration of the present invention, for example, the configuration of a printing device and program corresponding to the above can also be considered. In this case as well, for example, the same effects as above can be obtained. [Effects of the Invention]

[0020] According to the present invention, for example, the effects of defective nozzles can be appropriately reduced. [Brief explanation of the drawing]

[0021] [Figure 1] This is a diagram for explaining a printing apparatus 10 that executes a printing method according to an embodiment of the present invention. FIG. 1(a) shows an example of the configuration of the main part of the printing apparatus 10. FIG. 1(b) shows an example of the configuration of the head part 12 in the printing apparatus 10. FIG. 1(c) shows an example of the functional configuration of the control part 22 in the printing apparatus 10. [Figure 2] This is a diagram showing an example of the printing operation when the set number of passes is 1. FIG. 2(a) shows an example of the printing operation when the set number of passes is 1 and the MAPS speed is 100%. FIG. 2(b) shows an example of the printing operation when the set number of passes is 1 and the MAPS speed is 75%. [Figure 3] This is a diagram showing an example of the printing operation when the set number of passes is 2. FIG. 3(a) shows an example of the printing operation when the set number of passes is 2 and the MAPS speed is 100%. FIG. 3(b) shows an example of the printing operation when the set number of passes is 2 and the MAPS speed is 75%. [Figure 4] This is a diagram showing an example of the printing operation when the set number of passes is 2. FIG. 4(a) shows an example of the printing operation when the set number of passes is 2 and the MAPS speed is 66%. FIG. 4(b) shows a modified example of the printing operation when the set number of passes is 2 and the MAPS speed is 100%. [Figure 5] This is a diagram showing an example of the printing operation when the set number of passes is 4 and the MAPS speed is 100%. [Figure 6] This is a flowchart showing an example of the printing operation performed using the printing apparatus 10. [Figure 7] This is a flowchart showing an example of the detailed operation performed in step S106. [Figure 8] This is a diagram showing an example of the information to be displayed to the user during the operation of step S106. FIGS. 8(a) and (b) show an example of a dialog for requesting the user to make a selection.

Embodiments for Carrying Out the Invention

[0022] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 is a diagram illustrating a printing apparatus 10 that performs a printing method according to one embodiment of the present invention. Figure 1(a) shows an example of the configuration of the main parts of the printing apparatus 10. Figure 1(b) shows an example of the configuration of the head unit 12 in the printing apparatus 10. Figure 1(c) shows an example of the functional configuration of the control unit 22 in the printing apparatus 10. Except for the points described below, the printing apparatus 10 may have the same or similar features as a known printing apparatus. In addition, the printing apparatus 10 may further include configurations that are the same or similar as those of a known printing apparatus, in addition to the illustrated configuration. For example, the printing apparatus 10 may further include fixing means for fixing ink to the medium 50 to be printed. As fixing means, depending on the type of ink used in the printing apparatus 10, for example, a heater or an ultraviolet light source may be used.

[0023] In this example, the printing device 10 is an inkjet printer that performs color printing on a medium 50 using an inkjet method, and comprises a head unit 12, a platen 14, a main scanning drive unit 16, a sub-scanning drive unit 18, an input / output unit 20, and a control unit 22. The head unit 12 is the part that has an inkjet head 102 that ejects ink onto the medium 50. In this example, the head unit 12 has a plurality of inkjet heads 102y to k, which are distinguished and shown in Figure 1(b) by the reference numerals 102y to k. In this case, the inkjet head 102y ejects yellow (Y) ink. The inkjet head 102m ejects magenta (M) ink. The inkjet head 102c ejects cyan (C) ink. The inkjet head 102k ejects black (K) ink.

[0024] In this example, the multiple inkjet heads 102y~k are aligned in a predetermined sub-scanning direction (X direction in the figure) set in the printing device 10, and arranged in a line in the main scanning direction (Y direction in the figure) perpendicular to the sub-scanning direction. Furthermore, for the sake of explanation, features that do not require distinction between the inkjet heads 102y~k will be simply described as features of the inkjet head 102. For example, in this example, the inkjet head 102 has a nozzle row in which multiple nozzles are arranged. In the nozzle row, the multiple nozzles are arranged with their positions in the sub-scanning direction offset from each other. In this case, the nozzle row can be considered, for example, as a row in which multiple nozzles are arranged in a nozzle row direction parallel to the sub-scanning direction. Furthermore, the arrangement of the inkjet heads 102y~k may differ from the above. For example, the position of some of the inkjet heads 102 may be different from that of the other inkjet heads 102 in the sub-scanning direction.

[0025] The platen 14 is a table-shaped member that holds the medium 50 in a position opposite the head unit 12. The main scanning drive unit 16 is a drive unit that causes the inkjet head 102 in the head unit 12 to perform a main scanning operation (scan). The main scanning operation can be thought of as, for example, an operation in which ink is ejected while moving in the main scanning direction relative to the medium 50. The sub-scanning drive unit 18 is a drive unit that causes the inkjet head 102 in the head unit 12 to perform a sub-scanning operation. The sub-scanning operation can be thought of as, for example, an operation in the sub-scanning direction relative to the medium 50. In this example, the sub-scanning drive unit 18 causes the inkjet head 102 to perform a sub-scanning operation in between main scanning operations, thereby changing the area of ​​the medium 50 that is opposite the head unit 12. This also changes, for example, the range in which ink is ejected from the inkjet head 102 in the next main scanning operation on the medium 50. In this case, the sub-scanning drive unit 18 causes the inkjet head 102 to perform a sub-scan operation based on the sub-scanning movement amount set according to the printing conditions. The sub-scanning movement amount can be considered, for example, the amount by which the inkjet head 102 moves relative to the medium 50 in one sub-scan operation. More specifically, the sub-scanning drive unit 18 causes the inkjet head 102 to perform a sub-scan operation by transporting the medium 50 in a transport direction parallel to the sub-scanning direction. In this case, the sub-scanning operation can be considered, for example, an operation corresponding to the feed operation that sends the medium 50 relative to the head unit 12. Furthermore, the sub-scanning movement amount can be considered, for example, an amount of movement corresponding to the amount of medium 50 fed (feed amount).

[0026] As can be understood from the above explanation, the printing device 10 prints on the medium 50 by causing the inkjet head 102 to perform a main scanning operation and a sub-scanning operation. In this case, the printing device 10 performs the main scanning operation based on the set number of passes, which is a number set as an integer value of 1 or more. In addition, in this example, the printing device 10 can also perform printing operations using the MAPS (Mimaki Advanced Pass System) function, for example, according to the operating mode set by the user. The MAPS function will be explained in more detail later.

[0027] The input / output unit 20 is an interface unit that performs input and output of data and information to the printing device 10. In this example, the input / output unit 20 accepts, for example, input of print data (job) indicating the image to be printed. In this case, the input / output unit 20 receives the print data from, for example, a computer that generated the print data. The input / output unit 20 also performs, for example, displaying information to the user of the printing device 10 and accepting instructions. More specifically, the input / output unit 20 provides the user with, for example, displays prompts for selection regarding print conditions and various notifications. The input / output unit 20 also accepts from the user, for example, settings for the operating mode of the printing device 10, settings for print conditions, and responses to selections requested by the user. The input / output unit 20 may perform input and output of data and information via, for example, a computer that controls the operation of the printing device 10 (for example, a control PC). In this case, it can also be considered that this computer constitutes at least a part of the input / output unit 20.

[0028] The control unit 22 is, for example, the part of the printing device 10 that includes the CPU, and controls the operation of each part of the printing device 10 based on print data received via the input / output unit 20 and user instructions. In this example, the control unit 22 operates according to a program such as firmware, and functionally functions as, for example, a print control processing unit 202, a defective nozzle confirmation processing unit 204, a recovery confirmation processing unit 206, a condition search processing unit 208, and an input / output processing unit 210, as shown in Figure 1(c). In this case, the print control processing unit 202 can be considered, for example, a processing unit that controls the main scanning operation and the sub-scanning operation. In this example, the print control processing unit 202 controls the printing operation of the printing device 10 by, for example, causing the inkjet head 102 to perform the main scanning operation and the sub-scanning operation based on print conditions and print data set based on user instructions.

[0029] Furthermore, in this example, if a defective nozzle exists in any of the inkjet heads 102 in the head unit 12, the control unit 22, as necessary, operates as a defective nozzle confirmation processing unit 204, a recovery confirmation processing unit 206, and a condition search processing unit 208 to perform nozzle recovery processing to reduce the impact of the defective nozzle, or adjust the printing conditions. In this case, a defective nozzle can be considered, for example, a nozzle with poor ejection characteristics. Poor ejection characteristics can be considered, for example, a nozzle whose ejection characteristics are outside a predetermined normal range. A defective nozzle can be considered, for example, a nozzle that is unable to eject ink due to clogging or the like. In this example, the control unit 22 registers a nozzle as a defective nozzle if it does not become normal (cannot be restored) even after performing predetermined maintenance such as cleaning the inkjet head 102 or the nozzle. Furthermore, nozzle recovery can be considered, for example, a process that uses a different nozzle (hereinafter referred to as a substitute nozzle) when a defective nozzle exists. In this case, a substitute nozzle can be considered, for example, another nozzle used in place of the defective nozzle. More specifically, nozzle recovery can be considered as a process where, for example, an alternative nozzle ejects ink to the original ejection position of the faulty nozzle. In this case, the original ejection position of the faulty nozzle can be considered as, for example, the ejection position where ink would have been ejected if the faulty nozzle were a normal nozzle. In this case, the position of the faulty nozzle can be registered in advance, and in a main scan operation different from the one in which the faulty nozzle would have ejected ink to its original ejection position, the alternative nozzle can eject ink instead. With this configuration, for example, the impact of the faulty nozzle can be appropriately reduced.

[0030] Furthermore, the defective nozzle confirmation processing unit 204 can be considered, for example, as a processing unit that checks for the presence and location of defective nozzles in the inkjet head 102. The recovery confirmation processing unit 206 can be considered, for example, as a processing unit that checks whether nozzle recovery is possible for the defective nozzles confirmed by the defective nozzle confirmation processing unit 204. The condition search processing unit 208 can be considered, for example, as a processing unit that searches for new printing conditions when nozzle recovery is not possible. In addition, the defective nozzle confirmation processing unit 204, the recovery confirmation processing unit 206, and the condition search processing unit 208 perform these processes when, for example, the setting is configured to enable nozzle recovery in response to user instructions.

[0031] Furthermore, in this case, for example, if the defective nozzle confirmation processing unit 204 confirms the existence of a defective nozzle, and the recovery confirmation processing unit 206 confirms that nozzle recovery for the defective nozzle is possible, the recovery confirmation processing unit 206 instructs the print control processing unit 202 to control the operation of printing with nozzle recovery. On the other hand, if a defective nozzle exists but nozzle recovery is not possible, the recovery confirmation processing unit 206 instructs the condition search processing unit 208 to search for new printing conditions that will enable nozzle recovery. More specifically, in this example, as described above, a substitute nozzle is used in place of the defective nozzle during nozzle recovery. In this case, it is necessary to use a nozzle at a predetermined position determined according to the printing conditions, etc. Therefore, if, for example, the nozzle at the position of the substitute nozzle is also a defective nozzle, nozzle recovery cannot be performed. In this example, the condition search processing unit 208 searches for new printing conditions in such a case. The operation of the condition search processing unit 208 to search for new printing conditions will be explained in more detail later.

[0032] When the condition search processing unit 208 searches for new printing conditions, the input / output processing unit 210 prompts the user for confirmation regarding the search results and accepts instructions. The matters to be confirmed with the user in relation to the search for new printing conditions, and the instructions accepted from the user, will be explained in more detail later. In this example, for example, the control unit 22 can appropriately control the operation of the printing device 10. Furthermore, this enables, for example, the appropriate execution of printing operations on the medium 50.

[0033] Next, we will explain in more detail the MAPS function and other features used in the printing device 10. In this example, the printing operation using the MAPS function is an example of a path modulation operation. In this case, the path modulation operation can be thought of as, for example, an operation in which the number of times the main scanning operation performed on at least a part of the medium 50 is greater than the set number of passes. Also, as explained above, in this example, the set number of passes is a number set as an integer value of 1 or more. The set number of passes can be thought of as, for example, the number of passes at a reference integer value in the MAPS function.

[0034] More specifically, when printing with a printing device configured to perform main scanning and sub-scanning operations (a serial printing device), printing conditions can be set to, for example, resolution and number of passes. In this case, the number of passes can be considered as a setting value corresponding to the number of main scanning operations performed on the same position on the medium 50. In this case, the number of main scanning operations performed on the same position can be considered as, for example, the number of main scanning operations in which the inkjet head 102 passes over the position opposite to that position. The number of passes is usually set as an integer value, as in the above-mentioned set number of passes. In contrast, the MAPS function makes the number of main scanning operations performed on at least a part of the medium 50 greater than the set number of passes, as in the pass modulation operation described above. In this case, by changing the width in the sub-scanning direction of the area where the number of main scanning operations is increased, and the number of main scanning operations performed on that area, the average value of the number of main scanning operations is changed, including non-integer values. In this case, the average number of main scanning operations can be considered, for example, as the average number of times the inkjet head 102 passes over the position opposite to the position of the medium 50. Alternatively, the average number of main scanning operations can be considered, for example, as the average number of main scanning operations for each position in the sub-scanning direction.

[0035] Furthermore, in the MAPS function of this example, the printer 10 uses the MAPS speed as a set value in addition to the set number of passes. In this case, the MAPS speed is an example of the path modulation degree. The path modulation degree can be considered, for example, as a parameter indicating the degree of modulation that changes the number of main scanning operations performed on at least a portion of the medium 50 during the path modulation operation. In this example, the printer 10 also sets the sub-scanning movement amount in the sub-scanning operation according to the MAPS speed. In this case, as the sub-scanning movement amount changes according to the MAPS speed, for example, the area on the medium 50 in which more main scanning operations are performed than the set number of passes changes. Furthermore, as a result, the average number of main scanning operations also changes. Therefore, the MAPS speed can be considered, for example, as a parameter that corresponds to the average number of main scanning operations. In this example, the average number of main scanning operations changes in decimal units based on the set number of passes and the MAPS speed.

[0036] More specifically, in this example, the MAPS speed is set to a value in the range of 50% or more and 100% or less. In this case, a MAPS speed of 100% corresponds to the value when the set number of main scan operations are performed on the entire medium 50. A MAPS speed of 50% corresponds to the value when the set number of main scan operations are performed on the entire medium 50 twice the set number of main scan operations. In this case, the 100% MAPS speed can also be considered as the MAPS speed at which the average number of main scan operations is equal to the set number of passes. The 50% MAPS speed can also be considered as the MAPS speed at which the average number of main scan operations is equal to twice the set number of passes. Furthermore, as explained above, in this example, the MAPS speed is an example of path modulation. In this case, the 100% MAPS speed can be considered as the value corresponding to, for example, 100% path modulation. The 50% MAPS speed can be considered as the value corresponding to, for example, 50% path modulation. Furthermore, when the MAPS speed is greater than 50% and less than 100%, the average number of main scan operations can be considered to be greater than the set number of passes and less than twice the set number of passes. In this case, the average number of main scan operations can be considered to vary, for example, within a range greater than or equal to the set number of passes and less than or equal to twice the set number of passes, depending on the MAPS speed.

[0037] Furthermore, in the following, the average number of main scanning operations, which is determined according to the set number of passes and MAPS speed, is referred to as the half-pass number. The half-pass number can also be considered as, for example, the effective number of passes calculated as a decimal value based on the set number of passes and MAPS speed. Also, as mentioned above, in this example, the sub-scanning movement amount changes according to the MAPS speed. Therefore, the half-pass number can also be considered in relation to the sub-scanning movement amount. In this case, the half-pass number can be considered as, for example, the value obtained by dividing the nozzle row length in the inkjet head 102 by the sub-scanning movement amount. The nozzle row length can be considered as, for example, the width of the nozzle row in the sub-scanning direction. The nozzle row length can also be considered as, for example, the width in the sub-scanning direction of the range where the nozzles are lined up in the nozzle row of the inkjet head 102 that ejects one color of ink. Furthermore, in this regard, as the nozzle row of the inkjet head 102 that ejects one color of ink, it is also conceivable to use, for example, a virtual nozzle row composed of multiple inkjet heads arranged in a staggered configuration. In this case, the virtual nozzle row can be considered, for example, as a nozzle row formed by virtually connecting the nozzle rows of multiple inkjet heads into one. In such a case, the nozzle row length can be considered, for example, as the nozzle row length of such a virtual nozzle row.

[0038] Here, regarding the relationship between MAPS speed and sub-scanning movement, in this example, the sub-scanning movement is maximum when the MAPS speed is 100%. When the MAPS speed is reduced, the sub-scanning movement also decreases, and at a MAPS speed of 50%, the sub-scanning movement is minimum. In this case, reducing the MAPS speed reduces the sub-scanning movement, which in turn reduces the printing speed. Therefore, MAPS speed can be considered as a parameter that corresponds to, for example, the printing speed. Furthermore, when printing using the MAPS function, by adjusting the MAPS speed, the sub-scanning movement can be made smaller than the sub-scanning movement determined solely by the set number of passes, for example, making the path boundaries less noticeable. In this case, the sub-scanning movement determined solely by the set number of passes can be considered as, for example, the movement amount corresponding to the distance obtained by dividing the nozzle row length by the set number of passes. In this case, by making the sub-scanning movement smaller than this distance, for example, the edges of the paths can be diffused (dispersed), making the path boundaries less noticeable as described above.

[0039] More specifically, in this example, the control unit 22 (print control processing unit 202) manages multiple nozzles in the nozzle row of the inkjet head 102 by dividing them into path ranges equal to the number of set passes arranged sequentially in the sub-scanning direction. In this case, the path range can be considered, for example, as the range corresponding to one main scanning operation out of multiple main scanning operations performed on the position of the medium 50. Also, if the value obtained by dividing the nozzle row length by the set number of passes is defined as the pass width, the path range can be considered, for example, as the range equal to the pass width in the nozzle row. Furthermore, in this case, by repeating the main scanning operation and the sub-scanning operation, each path range passes over the same position and the opposite position on the medium 50. As a result, the printing device 10 performs multiple main scanning operations on the same position on the medium. And in this case, the area from which ink is ejected from a nozzle in one path range can be considered to correspond to the above-mentioned pass. Furthermore, the boundary of such an area can be considered as the path boundary.

[0040] Furthermore, the MAPS function uses a mask selected according to the set number of passes and MAPS speed to determine the ejection position of ink during the main scanning operation. In this case, in the area of ​​the mask corresponding to a region where more passes are performed than the set number, the ratio of selecting the ejection position (mask density) becomes smaller. Also, in this case, if the sub-scanning movement amount becomes smaller according to the MAPS speed setting, the area where more passes are performed than the set number becomes larger, including the pass boundary. As a result, for example, the edges of the passes become diffused, and the pass boundaries become less noticeable. Therefore, by using the MAPS function, it is possible to reduce the occurrence of banding and color unevenness, for example, where the pass boundaries are excessively noticeable, and to perform high-quality printing.

[0041] More specifically, in this example, printing can be performed using the MAPS function, for example, as shown in Figures 2-5. Figures 2-5 are simplified diagrams showing the printing operation performed using the MAP function. In Figures 2-5, for ease of illustration, an example of the printing operation is shown using a single inkjet head 102 (see Figure 1) with 16 nozzles. Furthermore, regarding the method of selecting the ejection position for ejecting ink in each main scanning operation, a simplified example is shown in the figures where the mask density is set to discrete values ​​such as 100%, 50%, 25%, and 0%, as indicated by the shading pattern, making the selection easy to illustrate. In an actual printing device 10 (see Figure 1), the inkjet head 102 may have more nozzles. Also, as a mask, a more complex mask may be used, for example, the same as or similar to that of the known MAPS function. In this case, for example, a mask with a gradient-like change in density can be suitably used. It is also conceivable to allow the user to select from multiple types of masks.

[0042] Furthermore, of Figures 2 to 5, Figure 2 shows an example of printing operation when the set number of passes is 1 (1 Pass). Figure 2(a) shows an example of printing operation when the set number of passes is 1 and the MAPS speed is 100%. In this case, the printing device 10 performs only one main scan operation for all positions on the medium. Therefore, the method of selecting the ejection position to eject ink in each main scan operation is a 100% selection, which selects all ejection positions. In this case, the method of selecting the ejection position can be considered, for example, as the method of selection when performing so-called solid color printing. Therefore, when performing printing other than solid color printing, for example, it can be considered that ink is ejected to the ejection position selected according to the image to be printed from among the ejection positions to which ink is ejected in solid color printing. Also, in this example, the sub-scanning travel amount is the distance obtained by multiplying the pass width, which is the value obtained by dividing the nozzle row length by the set number of passes, by the ratio of the MAPS speed. And, in the illustrated configuration, when the set number of passes is 1, the pass width is the width in the sub-scanning direction of 16 nozzles. Therefore, when the number of set passes is set to 1 and the MAPS speed is set to 100%, the sub-scan movement amount is equal to the width in the sub-scan direction for 16 nozzles.

[0043] Figure 2(b) also shows an example of printing operation when the number of set passes is 1 and the MAPS speed is 75%. In this case, the printer 10 performs only one main scan operation on a part of the medium and two main scan operations on the other part. More specifically, in the figure, the pattern on the left shows a simplified example of the ejection position where ink is ejected in the first main scan operation of two consecutive main scan operations. The pattern on the right shows a simplified example of the ejection position where ink is ejected in the second main scan operation. In this case, of the 16 nozzles lined up in the inkjet head 102, the method of selecting the ejection position where ink is ejected in each main scan operation is set to a 50% selection, which is half the ejection position in the 100% case, for the four nozzles on one end and the four nozzles on the other end in the sub-scanning direction. For the remaining eight nozzles in the center, the method of selecting the ejection position is set to a 100% selection. In this case, the sub-scanning travel amount is the width in the sub-scanning direction for 12 nozzles, which corresponds to 75% of the pass width. The number of half-passes is 1.33 (1.33 Pass). As a result, for positions where ink is ejected from nozzles selected for 100% of the time, the printing device 10 ejects 100% of the ink in one main scan operation (1 scan), as shown in the figure. In this case, for ejection positions where ink is ejected from nozzles selected for 50% of the time, the selection of ejection positions in two main scan operations is made complementary, so that ink is ejected in the second main scan operation for ejection positions where ink is not ejected in the first main scan operation. As a result, for positions where ink is ejected from nozzles selected for 50% of the time, the printing device 10 ejects 100% of the ink in two main scan operations (2 scans), as shown in the figure.

[0044] Figures 3 and 4 show examples of printing operation when the number of set passes is 2 (2Pass). Figure 3(a) shows an example of printing operation when the number of set passes is 2 and the MAPS speed is 100%. In this case, the method of selecting the ejection position for ejecting ink in each main scan operation is to select 50% for all nozzles. Also, in the illustrated configuration, when the number of set passes is 2, the pass width is the width in the sub-scan direction corresponding to 8 nozzles. Therefore, when the number of set passes is 2 and the MAPS speed is 100%, the sub-scan movement amount is equal to the width in the sub-scan direction corresponding to 8 nozzles, which corresponds to 100% of the pass width. As a result, the printing device 10 performs two main scan operations for all positions on the medium. Then, 100% ejection is performed by the two main scan operations (2 scans). Also, in this case, the number of half passes is 2 (2Pass).

[0045] Figure 3(b) shows an example of printing operation when the number of set passes is 2 and the MAPS speed is 75%. In this case, regarding the selection of the ejection position for ejecting ink in each main scan operation, of the 16 nozzles lined up in the inkjet head 102, the 4 nozzles on one end and the 4 nozzles on the other end in the sub-scan direction are selected to 25%, which is 1 / 4 of the ejection position in the 100% case. For the remaining 8 nozzles in the center, the method of selecting the ejection position is set to 50%. Also, when the number of set passes is 2 and the MAPS speed is 75%, the sub-scan movement amount is equal to the width in the sub-scan direction corresponding to 6 nozzles, which is 75% of the pass width. In this case, as shown in the figure, the printing device 10 performs 100% ejection on a part of the medium 50 with 2 main scan operations (2 scans). For the other part of the medium 50, 100% ejection is performed with 3 main scan operations (3 scans). In this case, the number of partial passes will be 2.66 (2.66 Pass).

[0046] Figure 4(a) shows an example of printing operation when the number of set passes is 2 and the MAPS speed is 66%. In this case, regarding the selection of the ejection position for ejecting ink in each main scan operation, in order to adjust for the fractional amount caused by the MAPS speed setting, one nozzle at the very end of the 16 nozzles lined up in the inkjet head 102 (the nozzle indicated by the number 16 in the figure) is set not to be used. Then, regarding the selection of the ejection position, of the remaining 15 nozzles, the selection of 5 nozzles on one end and 5 nozzles on the other end in the sub-scan direction is set to 25%. In addition, the selection of the ejection position for the remaining 5 nozzles in the center is set to 50%. Furthermore, when the number of set passes is 2 and the MAPS speed is 66%, the sub-scan movement amount is equal to the width in the sub-scan direction corresponding to 66% of the pass width, which is the width of 5 nozzles. In this case, the fact that the width in the sub-scanning direction for the five nozzles corresponds to 66% of the pass width can be considered, for example, that the width, which changes according to the number of nozzles (an integer value) under conditions where the sub-scanning operation can be performed properly, is closest to 66% of the pass width. Also, in this case, as shown in the figure, the printing device 10 performs 100% ejection for all positions of the medium 50 with three main scanning operations (3 scans). The number of half-passes is 3 (3 Pass).

[0047] Furthermore, as explained above, the mask used to determine the ejection position for ink ejection during the main scanning operation could be, for example, selected by the user from several types of masks. In this case, even if the set number of passes and MAPS speed are the same, the way the ink is ejected will change. For example, when the set number of passes is 2 and the MAPS speed is 100%, the printing operation could be performed as shown in Figure 4(b). Figure 4(b) shows a modified example of the printing operation when the set number of passes is 2 and the MAPS speed is 100%. In this case, regarding the method of selecting the ejection position for ink ejection during each main scanning operation, of the 16 nozzles lined up in the inkjet head 102, the two nozzles on one end and the two nozzles on the other end in the sub-scanning direction are selected to 0%, meaning no ink is ejected. Also, for the 3rd to 6th nozzles from the end on both the one end and the other end, the method of selecting the ejection position is set to 50%. Furthermore, for the remaining four nozzles in the center, the method of selecting the ejection position is set to 100%. In this case as well, since the number of set passes is 2 and the MAPS speed is 100%, the sub-scanning travel amount is equal to the width in the sub-scanning direction for 8 nozzles, which corresponds to 100% of the pass width. As shown in the figure, in this case as well, the printing device 10 ejects 100% of the material at all positions on the medium 50 with two main scanning operations (2 scans). The number of half-passes is 2 (2 Pass).

[0048] Furthermore, the printing operation using the MAPS function can be performed in the same or similar manner as described above, even when the number of set passes is greater. For example, when the number of set passes is 4, the printing operation can be performed as shown in Figure 5. Figure 5 shows an example of printing operation when the number of set passes is 4 (4Pass) and the MAPS speed is 100%. In this case, regarding the selection of the ejection position for ejecting ink in each main scan operation, 25% selection is made for all 16 nozzles lined up in the inkjet head 102. Also, when the number of set passes is 4, the pass width becomes the width in the sub-scan direction of 4 nozzles. Therefore, when the number of set passes is 4 and the MAPS speed is 100%, the sub-scan movement amount is equal to the width in the sub-scan direction of 4 nozzles, which corresponds to 100% of the pass width. In this case, the printing device 10 ejects 100% of the ink at all positions on the medium 50 with 4 main scan operations (4 scans). Also, the number of half passes becomes 4 (4Pass).

[0049] Next, the printing operation performed using the printing device 10 in this example will be explained in more detail using a flowchart. Figure 6 is a flowchart of an example of the printing operation performed using the printing device 10. In this example, the printing device 10 starts the printing operation (S102) when it receives a print start instruction from a computer that controls the operation of the printing device 10. After starting the printing operation, the printing device 10 performs a pre-configured print preparation operation (S104). In this example, the operation in step S104 is an example of the operation in the data acquisition stage and the condition setting stage. The processing performed in the operation in step S104 can be considered, for example, an example of data acquisition processing and condition setting processing. In step S104, the printing device 10 acquires print data indicating the image to be printed and sets the print conditions, which are the conditions for printing to be performed by the printing device 10, based on the print data. In this case, the print data can be considered, for example, print job data. As print data, for example, it is conceivable to acquire data generated by performing RIP processing according to the print resolution specified in advance by the user. Furthermore, as will be explained in more detail later, in this example, the printing device 10 adjusts the printing conditions as needed. Therefore, the printing conditions set in step S104 can be considered, for example, as initial values ​​for the printing conditions.

[0050] In step S104, the printing device 10 sets the printing conditions, such as the print resolution, the number of set passes, the MAPS speed, and the main scanning speed (scan speed). In this case, the main scanning speed can be considered as, for example, the speed at which the inkjet head moves relative to the medium during the main scanning operation. In addition, the setting of the main scanning speed can be considered as selecting one of several pre-set speeds. More specifically, in this case, for example, it can be considered as selecting either the standard speed, which is the standard main scanning speed, or the high speed, which moves the inkjet head faster than the standard speed. Also, as explained above, in this example, the sub-scanning movement amount is determined according to the number of set passes and the MAPS speed. Therefore, the operation in step S104 can be considered as setting the sub-scanning movement amount according to, for example, the MAPS speed. Furthermore, in step S104, the printing device 10 sets at least some of the printing conditions based on, for example, the information contained in the print data. The printer 10 may set at least some of the printing conditions based, for example, on information received from outside the printer 10 along with the print data. The printer 10 may also set at least some of the printing conditions based, for example, on manual operation by the user to the printer 10.

[0051] Furthermore, following the operation in step S104, the printing device 10 checks the printing conditions set in step S104 and adjusts the printing conditions as necessary (S106). In this example, the operation in step S106 is an example of the operation in the condition confirmation stage. The process performed in step S106 can be considered, for example, an example of the condition confirmation process. After checking the printing conditions in step S106, the printing device 10 performs the printing operation based on the print data and printing conditions (S108). In this example, the operation in step S108 is an example of the operation in the print execution stage. The process performed in step S108 can be considered, for example, an example of the print execution process. According to this example, for example, the printing operation based on the print data can be performed appropriately. Also, in this case, the operation in step S106 allows for appropriate adjustment of the printing conditions as necessary.

[0052] Next, we will explain in more detail the actions performed in step S106. In this example, at least part of the actions performed in step S106 may be actions performed when a predetermined operating mode is set. In this case, for example, if an operating mode that enables nozzle recovery is set, adjustments to the printing conditions may be made. Also, in this example, when adjusting the printing conditions, step S106 checks, for example, whether nozzle recovery for a defective nozzle is possible with the printing conditions set in step S104. If, as a result of the check, there is a defective nozzle for which nozzle recovery is impossible, the printing conditions are adjusted by lowering the MAPS speed to search for printing conditions that enable nozzle recovery. Furthermore, based on the results of the above check and search, the user is given a choice, for example, whether or not to change the printing conditions. More specifically, in step S106, for example, the printing conditions may be checked and adjusted as shown in Figures 7 and 8.

[0053] Figure 7 is a flowchart showing an example of a detailed operation performed in step S106. Figure 8 shows an example of information displayed to the user during the operation in step S106. Figures 8(a) and (b) show an example of a dialog box that displays information and prompts the user for selection. The operations described below can be considered, for example, an example of an operation performed when the printing device 10 is set to perform nozzle recovery (nozzle recovery is enabled). In addition, in the operation of step S106 in this example, the printing device 10 checks for the presence or absence of a defective nozzle and whether nozzle recovery is possible for the defective nozzle, for example, through processing performed by the control unit 22 as a defective nozzle confirmation processing unit 204 and a recovery confirmation processing unit 206 (S202). In this case, checking for the presence or absence of a defective nozzle can be considered, for example, by checking whether a defective nozzle exists in the nozzle row of any inkjet head 102 in the head unit 12. Also, in this example, the operation of step S202 is an example of the operation of the defective nozzle confirmation stage and the recovery confirmation stage. Furthermore, the processing performed in the operation of step S202 can be considered, for example, an example of the defective nozzle confirmation process and the recovery confirmation process. Furthermore, in step S202, the printing device 10 checks whether nozzle recovery is possible for a pre-registered defective nozzle, based on the printing conditions set in step S104 of the operation described with reference to Figure 6.

[0054] Furthermore, after confirming the presence or absence of defective nozzles and the feasibility of nozzle recovery in step S202, the printing device 10, for example, through a recovery confirmation processing unit 206 performed by the control unit 22, will perform different subsequent processes depending on whether or not there are defective nozzles that cannot be recovered (S204). More specifically, if there are no defective nozzles, or if there are defective nozzles but nozzle recovery is possible for all of them (S204, No), the device proceeds to step S108 without adjusting the printing conditions and executes the printing operation. In this case, the printing operation is performed based on the printing conditions set in step S104 in Figure 6, while performing nozzle recovery as necessary. On the other hand, if there are defective nozzles and nozzle recovery is impossible for at least one of them (S204, Yes), the device proceeds to the operations from step S206 onward to search for new printing conditions that will enable nozzle recovery. In this example, the operations performed from step S206 onward are an example of the operations in the condition search stage. Furthermore, the processes performed from step S206 onward can be considered, for example, an example of the condition search process. The condition search stage can be thought of as a stage in which new printing conditions are searched for when a defective nozzle exists and nozzle recovery is not possible.

[0055] Furthermore, in the operation from step S206 onward, the printing device 10 adjusts the printing conditions by changing the MAPS speed through processing performed by the control unit 22 as a condition search processing unit 208, for example, to search for printing conditions that enable nozzle recovery. In this case, the printing device 10 obtains the MAPS speed from among the printing conditions set in step S104 (S206), and changes the value of the obtained MAPS speed in predetermined increments (S208). In this example, the printing device 10 searches for printing conditions that enable nozzle recovery by changing the MAPS speed in the direction of decreasing the value in 1% increments. In this case, the 1% increment can be considered, for example, as an increment corresponding to 1 / 100 of 100% MAPS speed. The increment for changing the MAPS speed in step S208 may be other than 1%. In this case, it is preferable to change the MAPS speed in increments of 2% or less (for example, about 0.5 to 2%). With this configuration, for example, it becomes possible to appropriately adjust printing conditions without significantly changing the printing conditions themselves.

[0056] As explained above, in this example, the MAPS speed is set to a value in the range of 50% or more and 100% or less. Therefore, after changing the MAPS speed in step S208, a determination is made as to whether the changed MAPS speed is appropriate (S210). More specifically, in this example, the printer 10 determines whether the changed MAPS speed is less than 50%. If the changed MAPS speed is less than 50% (S210, Yes), the printer notifies the user that no new printing conditions that would enable nozzle recovery have been found and that nozzle recovery is no longer possible, and accepts the user's selection regarding subsequent actions (S212). In this case, the printer 10 notifies the user and accepts instructions from the user via the computer, for example, by displaying a dialog box on the monitor of the computer that controls the operation of the printer 10. More specifically, in step S212, the printer 10 notifies the user that no new printing conditions that would enable nozzle recovery have been found by displaying a dialog box, for example, as shown in Figure 8(a). Furthermore, the user is given the option to either cancel the print operation or continue printing. If "cancel print" is selected, the printer 10 cancels the print operation without proceeding to step S108. If "continue print" is selected, the printer proceeds to step S108 and executes the print operation, using the print conditions set in step S104 without changing them.

[0057] Furthermore, in this example, even if no new printing conditions enabling nozzle recovery are found by simply changing the MAPS speed, nozzle recovery may become possible by changing the number of set passes or the main scan speed. More specifically, when the number of set passes is changed, the sub-scan movement amount when the MAPS speed is 100% changes, which changes the conditions under which nozzle recovery becomes possible. Also, when the main scan speed is changed, the density of ejection positions where ink can be ejected from one nozzle in a single main scan operation changes, which may enable nozzle recovery. For example, if the main scan speed in the original printing conditions is high speed, changing the main scan speed to the standard speed may enable nozzle recovery. Therefore, in this example, under predetermined conditions, such as the display of the dialog shown in Figure 8(a), the user is prompted to change the number of set passes by suggesting the creation of a JOB with an increased number of passes corresponding to the print data with an increased number of set passes. Similarly, under the same predetermined conditions, the user is prompted to change the main scan speed (scan speed) by suggesting a change from a high-speed setting to a standard setting. In this case, the inability to find new printing conditions enabling nozzle recovery can be considered an example of predetermined conditions. Furthermore, the user may be prompted to change the number of passes or the main scan speed under other predetermined conditions. For example, if new printing conditions that enable nozzle recovery are found, and the reduction in printing speed due to these new printing conditions exceeds a predetermined standard, the user may be prompted to change the number of passes or the main scan speed.

[0058] Furthermore, if the changed MAPS speed is not less than 50% in step S210 (S210, No), the printing device 10 checks whether nozzle recovery is possible for defective nozzles with respect to the printing conditions using the changed MAPS speed, in the same or similar manner as in step S202 (S214). Following the operation in step S214, the printing device 10 checks whether nozzle recovery is possible for all defective nozzles, in the same or similar manner as in step S204 (S216). In this case, in steps S214 and S216, for example, the processing performed by the control unit 22 as the condition search processing unit 208 may be further performed as the defective nozzle confirmation processing unit 204 and the recovery confirmation processing unit 206 to perform the above processing. Furthermore, if it is determined in step S216 that nozzle recovery is not possible for at least one defective nozzle (S216, No), the process proceeds back to step S208 and the subsequent operations are repeated. Furthermore, this allows for further adjustments to the MAPS speed, for example, to explore new printing conditions.

[0059] Furthermore, in step S216, if it is determined that nozzle recovery is possible for all defective nozzles by using the modified MAPS speed (S216, Yes), new printing conditions that enable nozzle recovery have been found, and the user is notified that nozzle recovery is possible, and the user's selection regarding the subsequent operation is accepted (S218). In this case as well, the printing device 10 notifies the user and accepts instructions from the user via the computer, for example, by displaying a dialog box on the monitor of the computer that controls the operation of the printing device 10. More specifically, in step S218, the printing device 10 notifies the user that new printing conditions that enable nozzle recovery have been found by displaying a dialog box to the user, for example, as shown in Figure 8(b). The printing device also displays the printing speed corresponding to the MAPS speed under the new printing conditions, and allows the user to select one of the following actions regarding the subsequent operation: print cancellation to stop the printing operation, continue printing with the original settings, or continue printing with the new settings applied. In this case, continuing printing with the original settings can be considered as, for example, printing using the MAPS speed under the printing conditions set in step S104. Continuing printing with the new settings applied can be considered, for example, by printing using the MAPS speed changed in step S106.

[0060] If print cancellation is selected, the printer 10 stops the printing operation without proceeding to step S108. If the user selects to continue printing with the original settings, the printer proceeds to step S108 and executes the printing operation using the printing conditions set in step S104 without changing the printing conditions. This also ensures that nozzle recovery is not performed for at least some of the faulty nozzles. If the user selects to continue printing with the new settings, the printer proceeds to step S108 and executes the printing operation using the changed MAPS speed and performing nozzle recovery for all faulty nozzles. By displaying such a dialog, for example, if new printing conditions that enable nozzle recovery are found, the user can choose to either execute printing using the new printing conditions or execute printing without nozzle recovery using the new printing conditions. Therefore, according to this example, the printer 10 can more appropriately execute the printing operation based on the print data based on the user's selection received during the operation to search for new printing conditions.

[0061] Furthermore, when considering high-quality printing by performing nozzle recovery, it might seem that the system should automatically adopt new printing conditions without requiring the user to choose whether or not to adopt them. In fact, depending on the purpose of printing, it may be preferable to automatically adopt new printing conditions. However, if the MAPS speed is changed slightly, the printing speed will decrease proportionally to the amount of the change. As a result, the time it takes to complete printing will increase, and it may not be possible to finish printing by the time the user desires. Also, if the amount of the MAPS speed is changed significantly, even if the print quality improves, the change in print quality may result in printing at the quality the user desires. In contrast, as in this example, by displaying the dialog box described above, the user can appropriately choose whether or not to adopt new printing conditions. This also allows for more appropriate execution of printing with printing conditions tailored to the user's preferences.

[0062] Next, we will provide supplementary explanations regarding the configuration described above. As explained above, in this example, the nozzle used between passes can be changed by changing the MAPS speed in the MAPS function. This also allows for the appropriate change of the nozzle that can be used as a replacement nozzle for a defective nozzle. Therefore, according to this example, even if nozzle recovery is not possible under the initial printing conditions, it is possible to appropriately search for new printing conditions that enable nozzle recovery. Furthermore, in this case, by changing the MAPS speed, it becomes possible to use conditions that do not change the number of set passes or the print resolution as new printing conditions that enable nozzle recovery. Therefore, according to this example, it is possible to appropriately reduce the impact of a defective nozzle while appropriately preventing large changes in print quality or a significant decrease in printing speed. In addition, in this case, nozzle recovery can be appropriately performed without, for example, recreating the print data (job) or replacing the inkjet head. This also allows for the efficient production of printed materials by appropriately preventing rework and temporary production interruptions.

[0063] Furthermore, in this example, the search for printing conditions that enable nozzle recovery can also be considered by focusing on the sub-scan movement amount. In this case, the operation of searching for new printing conditions can be thought of as searching for printing conditions that enable nozzle recovery by changing the sub-scan movement amount, for example. More specifically, in this case, the operation of searching for new printing conditions can be thought of as searching for printing conditions that enable nozzle recovery by changing the MAPS speed, for example, by changing the sub-scan movement amount corresponding to the MAPS speed. In this case, as explained above, the MAPS speed is kept below 100% and varied within a range of 50% or more. And in this case, the sub-scan movement amount will be varied within a range of 0.5 times or more and 1 time or less of the path width. With this configuration, for example, it is possible to appropriately search for new printing conditions that enable nozzle recovery.

[0064] Furthermore, as described above, in this example, the operation to search for new printing conditions involves changing the MAPS speed in the direction of decreasing the MAPS speed. In this case, the MAPS speed can be considered as being changed in a direction that improves print quality, for example. With this configuration, it is possible to appropriately search for new printing conditions while maintaining the print quality desired by the user. Alternatively, depending on the print quality and printing time desired by the user, the MAPS speed may be changed in the direction of increasing the MAPS speed, which may decrease print quality, in order to search for new printing conditions. For example, if nozzle recovery is not possible even when the MAPS speed is changed to less than 50%, or if the change in MAPS speed becomes too large when decreasing the MAPS speed, it is conceivable to increase the MAPS speed to search for new printing conditions that enable nozzle recovery.

[0065] As explained above, in this example, when new printing conditions are found, the printer 10 allows the user to choose whether or not to adopt the new printing conditions. In contrast, in a modified version of the printing operation, it is conceivable that, under predetermined conditions, the new printing conditions could be automatically adopted without requiring user selection. More specifically, for example, in the operation of searching for new printing conditions, if new printing conditions that enable nozzle recovery are found, the printer 10 may further determine whether or not the new printing conditions match pre-registered conditions. If they match, the printer 10 may then execute the printing operation based on the print data using the new printing conditions without allowing the user to choose whether or not to execute printing using the new printing conditions. With this configuration, for example, the printing operation with new printing conditions can be executed more efficiently. Furthermore, whether or not to continue such automatic printing operations may be switched, for example, depending on the operating mode set for the printer 10. In this case, for example, when in a predetermined operating mode, the new printing conditions are automatically adopted as described above. Furthermore, depending on the configuration of the printing device 10, for example, in a predetermined operating mode, the user selection may always be omitted, and new printing conditions may be automatically adopted.

[0066] Furthermore, depending on the required print quality and purpose, it may be necessary to use stricter criteria to judge changes in print quality or decreases in print speed resulting from changes in printing conditions. Also, even if new printing conditions are found that enable nozzle recovery, it may be desirable to cancel the printing operation rather than adopting the new conditions. In this example, for example, the user can cancel the printing operation by selecting "Cancel Print" in response to the dialog box shown in Figure 8(b). In a modified version of the printing operation, for example, the printing operation may be automatically canceled based on predetermined conditions. In this case, during the operation to search for new printing conditions, the printing device 10 determines whether the new printing conditions match, for example, the registered conditions for canceling printing. If they match, the printing operation is automatically canceled without, for example, confirming the user's intention. With this configuration, for example, the printing operation can be appropriately canceled under predetermined conditions. As printing cancellation conditions, for example, it is conceivable to register conditions that correspond to situations such as when the print quality deviates from a predetermined acceptable range or when the printing time increases by a predetermined percentage, depending on the print quality and printing speed requested by the user.

[0067] Furthermore, as explained above, in this example, if no new printing conditions that enable nozzle recovery are found, the printer 10 prompts the user to change the set number of passes or the main scanning speed by displaying a dialog box, for example, as shown in Figure 8(a). In response to this, depending on the purpose of printing, the printer may automatically change other conditions besides the MAPS speed during the process of searching for new printing conditions. In this case, for example, it is conceivable to further change both or either the set number of passes and the main scanning speed to search for new printing conditions that enable nozzle recovery. With this configuration, for example, it is possible to search for printing conditions that enable nozzle recovery from a larger number of conditions. Furthermore, this makes it possible to appropriately search for more favorable new printing conditions, for example, depending on the purpose of printing. In this case, for example, it is conceivable to search for conditions that allow printing to continue with the least reduction in printing speed as new printing conditions. With this configuration, for example, it is possible to present more appropriate new printing conditions to the user. [Industrial applicability]

[0068] The present invention can be suitably used, for example, in printing methods. [Explanation of symbols]

[0069] 10...Printing device, 102...Inkjet head, 12...Head unit, 14...Platen, 16...Main scanning drive unit, 18...Sub-scanning drive unit, 20...Input / output unit, 202...Print control processing unit, 204...Defective nozzle confirmation processing unit, 206...Recovery confirmation processing unit, 208...Condition search processing unit, 210...Input / output processing unit, 22...Control unit, 50...Media

Claims

1. A printing method that uses a printing device to perform printing, The data acquisition stage involves obtaining print data that indicates the image to be printed, and A condition setting step in which printing conditions, which are the conditions for printing to be performed by the aforementioned printing device, are set. A condition confirmation stage is performed to confirm the print conditions set in the condition setting stage, A print execution step in which the printing device is instructed to perform a print operation based on the print data. Equipped with, The printing apparatus includes an inkjet head having a nozzle row in which multiple nozzles are arranged, and prints on the medium by causing the inkjet head to perform a main scanning operation in which it moves relative to the medium to be printed in a predetermined main scanning direction and ejects ink, and a sub-scanning operation in which it moves relative to the medium in a sub-scanning direction perpendicular to the main scanning direction, and can perform a path modulation operation in which the main scanning operation is performed on at least a portion of the medium and the number of times the main scanning operation is performed is greater than the number of sets, based on a set number of passes which is set to an integer value of 1 or more. In the condition setting step, as the printing condition, set a path modulation degree that indicates the degree of modulation that changes the number of times the main scanning operation is performed on at least a part of the medium in the path modulation operation, The aforementioned condition confirmation step is, A defective nozzle confirmation step is to confirm whether or not a defective nozzle, which is a nozzle with poor ejection characteristics, is present in the nozzle row of the inkjet head. A recovery confirmation step to confirm whether nozzle recovery is possible using a nozzle different from the defective nozzle when the defective nozzle exists, This is a step in which, if a defective nozzle exists and nozzle recovery is impossible, a new printing condition is searched for, and this condition search step is to search for a printing condition that enables nozzle recovery by changing the path modulation degree. Equipped with, A printing method characterized in that, in the pass modulation operation, the average value of the number of times the inkjet head passes through a position opposite to the position of the medium in the main scanning operation is varied within a range of more than or equal to the set number of passes and less than or equal to twice the set number of passes, based on the pass modulation degree.

2. The path modulation degree is a parameter that corresponds to a value of 100% when the main scan operation is performed for the set number of paths over the entire medium, and to a value of 50% when the main scan operation is performed for twice the set number of paths over the entire medium. The printing method according to claim 1, characterized in that, in the condition search stage, the path modulation degree is changed in an increment width such that the value corresponding to 100% is 2% or less, in order to search for the printing conditions that enable nozzle recovery.

3. The printing method according to claim 2, characterized in that, in the condition search stage, the path modulation degree is changed within a range that is less than or equal to the value corresponding to 100% and greater than or equal to the value corresponding to 50%.

4. In the condition setting step, the sub-scanning movement amount, which is the amount by which the inkjet head moves relative to the medium in one sub-scanning operation, is set according to the path modulation degree. The printing method according to claim 1, characterized in that, in the condition search stage, the sub-scanning amount corresponding to the path modulation is changed by changing the path modulation, thereby searching for the printing conditions that enable nozzle recovery.

5. If, during the condition search stage, a new printing condition is found that enables nozzle recovery, Print using the new printing conditions, Whether to perform printing without using the new printing conditions and without performing nozzle recovery. The user is asked to choose one of the following options. The printing method according to claim 1, characterized in that, in the printing execution stage, the printing device is made to perform a printing operation based on the print data based on the user's selection received in the condition search stage.

6. If, during the condition search stage, a new printing condition that enables nozzle recovery is found, the system further determines whether the new printing condition matches any of the pre-registered conditions. If it matches, the system does not require the user to choose whether or not to perform printing using the new printing condition. The printing method according to claim 5, characterized in that, in the printing execution stage, the printing device is made to perform a printing operation based on the print data using the new printing conditions.

7. The printing method according to claim 1, characterized in that, in the condition search stage, it is determined whether the new printing conditions match the printing cancellation conditions registered as conditions for canceling printing, and if they match, the printing operation is canceled.

8. The printing method according to claim 1, characterized in that, in the condition search step, the number of set passes and the main scanning speed, which is the speed at which the inkjet head is moved relative to the medium during the main scanning operation, are further changed to search for the printing conditions that enable nozzle recovery.

9. The printing method according to claim 1, characterized in that, under predetermined conditions, during the condition search stage, the user is prompted to change the main scanning speed, which is the speed at which the inkjet head moves relative to the medium during the main scanning operation.

10. The printing method according to claim 1, characterized in that, under predetermined conditions, the user is prompted to change the number of set passes.

11. A printing apparatus that performs printing, An inkjet head having a nozzle row with multiple nozzles arranged in a line, A main scanning drive unit causes the inkjet head to perform a main scanning operation, which involves moving in a predetermined main scanning direction relative to the printing medium and ejecting ink. A sub-scanning drive unit causes the inkjet head to perform a sub-scanning operation, which moves relative to the medium in a sub-scanning direction perpendicular to the main scanning direction. The control unit controls the operation of the inkjet head, the main scanning drive unit, and the sub-scanning drive unit. Equipped with, Printing is performed on the medium by having the inkjet head perform the main scanning operation and the sub-scanning operation, and the main scanning operation is executed based on a set number of passes, which is a number set to an integer value of 1 or more, and a pass modulation operation is possible in which the number of times the main scanning operation is performed on at least a part of the medium is greater than the set number of passes. The control unit, A data acquisition process to obtain print data indicating the image to be printed, A condition setting process for setting print conditions, which are the conditions for printing to be performed by the aforementioned printing device, A condition confirmation process that confirms the print conditions set in the condition setting process, A print execution process that causes the printing device to perform a print operation based on the print data. Execute, In the condition setting process, as the printing condition, set a path modulation degree that indicates the degree of modulation that changes the number of times the main scanning operation is performed on at least a part of the medium in the path modulation operation, In the condition confirmation process, the control unit, A defective nozzle confirmation process to confirm whether or not a defective nozzle, which is a nozzle with poor ejection characteristics, is present in the nozzle row of the inkjet head, A recovery confirmation process to check whether nozzle recovery is possible using a nozzle different from the defective nozzle when the defective nozzle exists, A process for searching for new printing conditions when a defective nozzle exists and nozzle recovery is impossible, the process for searching for printing conditions that enable nozzle recovery by changing the path modulation degree. Execute, A printing apparatus characterized in that, in the pass modulation operation, the average value of the number of times the inkjet head passes through a position opposite to the position of the medium in the main scanning operation is varied within a range of more than or equal to the set number of passes and less than or equal to twice the set number of passes, based on the pass modulation degree.

12. A program that controls the operation of a printing device, A data acquisition process to obtain print data indicating the image to be printed, A condition setting process for setting print conditions, which are the conditions for printing to be performed by the aforementioned printing device, A condition confirmation process that confirms the print conditions set in the condition setting process, A print execution process that causes the printing device to perform a print operation based on the print data. The printing device is made to perform this action. The printing apparatus includes an inkjet head having a nozzle row in which multiple nozzles are arranged, and prints on the medium by causing the inkjet head to perform a main scanning operation in which it moves relative to the medium to be printed in a predetermined main scanning direction and ejects ink, and a sub-scanning operation in which it moves relative to the medium in a sub-scanning direction perpendicular to the main scanning direction, and can perform a path modulation operation in which the main scanning operation is performed on at least a portion of the medium and the number of times the main scanning operation is performed is greater than the number of sets, based on a set number of passes which is set to an integer value of 1 or more. In the condition setting process, as the printing condition, set a path modulation degree that indicates the degree of modulation that changes the number of times the main scanning operation is performed on at least a part of the medium in the path modulation operation, In the aforementioned condition confirmation process, A defective nozzle confirmation process to confirm whether or not a defective nozzle, which is a nozzle with poor ejection characteristics, is present in the nozzle row of the inkjet head, A recovery confirmation process to check whether nozzle recovery is possible using a nozzle different from the defective nozzle when the defective nozzle exists, A process for searching for new printing conditions when a defective nozzle exists and nozzle recovery is impossible, the process for searching for printing conditions that enable nozzle recovery by changing the path modulation degree. The printing device is made to perform this action. A program characterized in that, in the path modulation operation, the average value of the number of times the inkjet head passes through a position opposite to the position of the medium in the main scanning operation is varied within a range of more than or equal to the set number of passes and less than or equal to twice the set number of passes, based on the degree of path modulation.

13. A printing method using a printing apparatus equipped with an inkjet head having a nozzle row in which a plurality of nozzles are arranged, Set the printing conditions, which are the conditions for printing to be performed by the aforementioned printing device. Printing is performed by causing the inkjet head to perform a main scanning operation in which it moves in a predetermined main scanning direction relative to the medium to be printed and ejects ink. The aforementioned main scan operation is performed based on one or more set number of passes. When a defective nozzle exists that has poor discharge characteristics, it is confirmed whether nozzle recovery is possible using a nozzle different from the defective nozzle. If nozzle recovery is not possible, the printing conditions include setting a path modulation degree that indicates the degree of modulation that changes the number of times the main scanning operation is performed on at least a portion of the medium, A printing method characterized by varying the average number of times the inkjet head passes through a position opposite to the position of the medium in the main scanning operation, based on the pass modulation degree, within a range of more than or equal to the set number of passes and less than or equal to twice the set number of passes.

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