JP2021066064A - Liquid discharge device, liquid discharge method and program - Google Patents

Abstract

To improve a drying property of a discharged liquid without degrading quality of a product formed by discharging the liquid.SOLUTION: A liquid discharge device includes a liquid discharge head which discharges a liquid on a recording medium, a movement mechanism which moves the liquid discharge head in a main scanning direction, and a movement mechanism which moves the recording medium or the liquid discharge head in a sub scanning direction. A predetermined total discharge amount of the liquid is discharged on the recording medium by a unit discharge amount per unit time by a plurality of times of scanning and a plurality of times of movement in the sub scanning direction. A determination part determines a discharge condition of discharging the predetermined total discharge amount of the liquid so that a scanning period corresponding to the plurality of times of scanning includes a first period, and a second period after the first period, and a second unit discharge amount indicating a unit discharge amount in the second period is smaller than a first unit discharge amount indicating a unit discharge amount in the first period, and the number of scanning of the plurality of times of scanning becomes larger than a number obtained when the predetermined total discharge amount is divided by the first unit discharge amount.SELECTED DRAWING: Figure 4

Description

The present invention relates to a liquid discharge device, a liquid discharge method and a program.

When printing color ink on top of white ink, if the white ink is not sufficiently dried, the color ink will be buried below the white ink, causing a decrease in density and bleeding (degradation of image quality). In some cases. Under these circumstances, in order to suppress the burial of color ink, the carriage is stopped during scanning and the amount of white ink injected is reduced to dry the white ink on the medium (recording medium). There is a technology to encourage.

In Patent Document 1, in order to suppress the shading of the image caused by the non-uniformity of the dry state of the ink applied first, the amount of the ink applied first is reduced to reduce the ejection amount on the recording medium. A technique for improving the dryness of an ink by reducing the area where the ink applied first and the ink applied later overlap is disclosed.

However, when printing color ink (ink to be applied later) on white ink (ink to be applied first), it is difficult to reduce the area where the white ink and the color ink overlap. Further, when the amount of white ink applied is reduced, there is a problem that the hiding rate of the medium by the white ink is lowered (image quality is lowered).

The present invention has been made in view of the above, and an object of the present invention is to improve the dryness of the discharged liquid without deteriorating the quality of the product formed by discharging the liquid.

In order to solve the above-mentioned problems and achieve the object, the present invention comprises a liquid discharge head that discharges liquid to a recording medium, a main scanning movement mechanism that moves the liquid discharge head in the main scanning direction, and the recording medium. Alternatively, it is provided with a sub-scan movement mechanism that moves the liquid discharge head in the sub-scan direction, and discharges a predetermined total discharge amount of liquid per unit time by performing a plurality of scans and a plurality of movements in the sub-scan direction. A liquid discharge device that discharges a unit discharge amount, which is an amount, onto the recording medium, and a scanning period indicating a period corresponding to the plurality of scans is a first period and a second after the first period. The second unit discharge amount indicating the unit discharge amount in the second period including the second period is less than the first unit discharge amount indicating the unit discharge amount in the first period, and the plurality of times A liquid comprising a determination unit for determining a discharge condition for discharging the predetermined total discharge amount so that the number of scans of the scan is larger than the number obtained by dividing the predetermined total discharge amount by the first unit discharge amount. It is a discharge device.

According to the present invention, there is an effect that the drying property of the discharged liquid can be improved without deteriorating the quality of the product formed by discharging the liquid.

FIG. 1 is a diagram showing an outline of the configuration of an image forming apparatus (liquid discharging apparatus) according to the first embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of the image forming apparatus of FIG. FIG. 3 is a diagram showing an outline of the configuration of the heater of FIG. FIG. 4 is a block diagram showing an example of the function of the control device of FIG. FIG. 5 is a diagram schematically showing a state in which the carriage of FIG. 2 is viewed from above. FIG. 6 is a diagram for explaining an example of the white printing mode realized by the control device of FIG. FIG. 7-1 is a diagram for explaining the improvement of dryness by the white printing mode of FIG. 7. FIG. 7-2 is a diagram for explaining the improvement of dryness by the white printing mode of FIG. 7. FIG. 8 is a flowchart showing an example of a flow of determining the white print mode executed by the control device of FIG. FIG. 9 is a diagram for explaining another example of the white printing mode realized by the control device of FIG. FIG. 10 is a flowchart showing another example of the flow of determining the white print mode executed by the control device of FIG. FIG. 11-1 is a diagram for explaining the detection of the image density by the sensor, which is carried out in the flow of determining the white print mode of FIG. FIG. 11-2 is another diagram for explaining the detection of the image density by the sensor, which is carried out in the flow of determining the white print mode of FIG.

Hereinafter, embodiments of the liquid discharge device, the liquid discharge method, and the program according to the present invention will be described in detail with reference to the accompanying drawings.

The techniques according to the present embodiment include a liquid discharge head that discharges liquid to a recording medium, a main scanning movement mechanism that moves the liquid discharge head in the main scanning direction, and the recording medium or the liquid discharge head in the sub-scanning direction. The recording medium is provided with a sub-scan moving mechanism for moving, and by performing a plurality of scans and a plurality of movements in the sub-scan direction, a predetermined total discharge amount of liquid is discharged in units of unit discharge amounts per unit time. In the liquid discharge device that discharges onto the above, the scanning period indicating the period corresponding to the plurality of scans includes the first period and the second period after the first period, and is in the second period. The second unit discharge amount indicating the unit discharge amount is smaller than the first unit discharge amount indicating the unit discharge amount in the first period, and the number of scans of the plurality of scans is the predetermined total discharge amount. It is characterized in that the discharge conditions for discharging the liquid having the predetermined total discharge amount are determined so as to be larger than the number divided by the first unit discharge amount. According to these configurations, the drying property of the discharged liquid can be improved without deteriorating the quality of the product formed by discharging the liquid.

Hereinafter, as an example of the liquid discharge device to which the present invention is applied, an image forming device which is one aspect of the liquid discharge device will be described as an example, but the present invention is not limited to this. The technique according to the embodiment can be applied to other liquid discharge devices of an image forming device such as a three-dimensional modeling device, a processing liquid coating device, and an injection granulation device.

(First Embodiment)
FIG. 1 is a diagram showing an outline of the configuration of an image forming apparatus 100 (liquid discharging apparatus) according to the present embodiment. As shown in FIG. 1, it is assumed that the image forming apparatus 100 according to the present embodiment is a wide serial type inkjet recording apparatus.

As shown in FIG. 1, the image forming apparatus 100 includes side plates 21A and 21B on the left and right sides of the apparatus main body 100a. The side plates 21A and 21B horizontally lay the main guide rod 31 which is a guide member. Further, the image forming apparatus 100 includes a sub-sheet metal guide 32. The main guide rod 31 and the sub sheet metal guide 32 slidably hold the carriage 121. The carriage 121 moves and scans in the direction of arrow A (carriage main scanning direction) via a timing belt that is rotationally driven by the main scanning motor 117. Further, the carriage 121 is equipped with an optical sensor 37 that detects an end portion (paper edge portion) of the medium P.

The carriage 121 has various colors such as yellow (Y), cyan (C), magenta (M), black (K), orange (O), green (G), and clear (Cl), depending on the mounted ink cartridge 10. The liquid ejection heads (recording heads) 122a, 122b, 122c (when not distinguished, they are referred to as "liquid ejection head 122") are provided. The liquid discharge head 122 arranges a nozzle array composed of a plurality of nozzles in the sub-scanning direction. Here, the sub-scanning direction (direction of arrow B) is a direction orthogonal to the main scanning direction of the carriage (direction of arrow A). The liquid ejection head 122 is mounted so that the ink droplet ejection direction from the nozzle is directed downward. The liquid discharge heads 122a, 122b, and 122c are installed so as to be offset in the sub-scanning direction, respectively. The carriage 121 is equipped with a sub tank in order to supply ink of each color corresponding to the liquid discharge head 122.

The image forming apparatus 100 includes a cartridge loading unit 1 for detachably mounting ink cartridges 10y, 10c, 10m, and 10k of each color (referred to as “ink cartridge 10” when not distinguished). The ink of the ink cartridge 10 is replenished and supplied to the sub tank of the carriage 121 by the supply pump unit via the supply tubes 36 of each color. The ink cartridge 10 may include a white ink cartridge.

The image forming apparatus 100 includes a maintenance / recovery mechanism 81 in a non-printing area on one side of the carriage 121 in the main scanning direction. The maintenance / recovery mechanism 81 maintains and / or recovers the state of the nozzle of the liquid discharge head 122. The maintenance / recovery mechanism 81 includes cap members (hereinafter referred to as “caps”) 82a, 82b, 82c (hereinafter referred to as “caps 82” when not distinguished) for capping each nozzle surface of the liquid discharge head 122, and nozzles. A wiping unit 83 for wiping the surface is provided. Further, a replaceable waste liquid tank for accommodating the waste liquid generated by the maintenance / recovery operation is provided below the maintenance / recovery mechanism 81 of the liquid discharge head 122.

FIG. 2 is a block diagram showing an example of the hardware configuration of the image forming apparatus 100 of FIG. As shown in FIG. 2, the image forming apparatus 100 includes a control device 101, an operation panel 114, an environment sensor 115, a head driver 116, a main scanning motor 117, an auxiliary scanning motor 118, a fan 119, a heater 120, a carriage 121, and a transfer roller. 123 is provided.

As shown in FIG. 2, the control device 101 includes a CPU (Central Processing Unit) 102, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 104, a non-volatile memory (NVRAM: Non-Volatile RAM) 105, and an ASIC. (Application Specific Integrated Circuit) 106, I / F 107, print control unit 108, main scanning motor drive unit 109, sub-scanning motor drive unit 110, fan control unit 111, heater control unit 112, and I / O 113. CPU 102, ROM 103, RAM 104, non-volatile memory 105, ASIC 106, I / F 107, print control unit 108, main scanning motor drive unit 109, sub-scanning motor drive unit 110, fan control unit 111, heater control unit 112 and I / O 113 , For example, they are connected to each other so as to be able to communicate with each other via a bus or the like.

The CPU 102 controls the operation of the entire image forming apparatus 100. Specifically, the CPU 102 realizes each function by executing a program stored in the ROM 103 or the like. The ROM 103 stores a program executed by the CPU 102, other fixed data, and the like. The RAM 104 temporarily stores image data and the like. The non-volatile memory 105 holds data even while the power supply of the image forming apparatus 100 is cut off. The ASIC 106 is a circuit for processing various signal processing, image processing for rearranging, and other input / output signals for controlling the entire device.

The I / F 107 is an interface circuit for transmitting and receiving data and signals to and from the host side. Specifically, the I / F 107 receives print data (image data) generated by a printer driver of a host such as an information processing device, an image reading device, and an imaging device via a cable, a network, or the like. That is, the print data generated and output to the control device 101 may be generated and output by the printer driver on the host side.

The print control unit 108 generates a drive waveform for driving the liquid discharge head 122, and selectively drives the pressure generating means for generating the pressure for the liquid discharge head 122 to discharge the liquid (ink) from the nozzles. This is a circuit for outputting data and various data associated therewith to the head driver 116.

The main scanning motor drive unit 109 is a circuit for driving the main scanning motor 117. The sub-scanning motor drive unit 110 is a circuit for driving the sub-scanning motor 118. The fan control unit 111 is a circuit for controlling the output of the fan 119 so that air is blown at a predetermined temperature and air volume. The heater control unit 112 is a circuit for controlling the heater 120 so that the temperature becomes a set temperature. The I / O 113 is a circuit for acquiring information from the environment sensor 115 and extracting information required for controlling each part of the image forming apparatus 100. The I / O 113 also inputs detection signals from various sensors other than the environment sensor 115.

The operation panel 114 is a device for inputting and displaying various information such as a user-specified resolution. The operation panel 114 is connected to the CPU 102 and the like so as to be able to communicate with each other via, for example, the bus of the control device 101. The environmental sensor 115 is, for example, a sensor that detects environmental temperature, environmental humidity, and the like. The environment sensor 115 is connected to the I / O 113 of the control device 101.

The head driver 116 selectively sends drive pulses constituting a drive waveform given by the print control unit 108 to the pressure generating means of the liquid discharge head 122 based on the input image data (for example, dot pattern data). This is a circuit for driving the liquid discharge head 122 by applying the liquid. The head driver 116 is connected to the print control unit 108 of the control device 101. The discharge amount is controlled, for example, by controlling the amplitude of the drive waveform input to the pressure generating means of the liquid discharge head 122, but the discharge amount may be controlled by using other means.

The main scanning motor 117 is a device that rotationally drives the timing belt by driving to move the carriage 121 including the liquid discharge head 122 in the main scanning direction (direction of arrow A). The main scanning motor 117 is connected to the main scanning motor drive unit 109 of the control device 101.

The sub-scanning motor 118 is a device that operates a transport roller 123 that, by driving, conveys the medium P, which is an object to be ejected liquid (ink) by the liquid ejection head 122, in the sub-scanning direction (direction of arrow B). is there. The sub-scanning motor 118 is connected to the sub-scanning motor drive unit 110 of the control device 101.

The fan 119 is a device for promoting convection of air inside the image forming apparatus 100 by driving and preventing the upper part of the image forming apparatus 100 from excessively rising in temperature due to the retention of warmed air. The fan 119 is connected to the fan control unit 111 of the control device 101.

FIG. 3 is a diagram showing an outline of the configuration of the heater 120 of FIG. In the example shown in FIG. 3, for the sake of simplicity, two liquid discharge heads 122a and 122b are shown as the liquid discharge head 122, and the description of the liquid discharge head 122c is omitted.

As shown in FIG. 3, the heater 120 includes a preheater 120a, a print heater 120b, a print heater 120c, a post heater 120d, and a drying heater 120e. Each of these heaters 120 is provided with a temperature sensor such as a thermistor for temperature control.

The preheater 120a is a device that preheats the medium P to a temperature suitable for forming the liquid coating surface. For example, the preheater 120a (upper margin + 2 ° C., lower margin 0 ° C.) is an aluminum foil cord heater. The preheater 120a is attached to the back surface of the transport guide plate 130. The preheater 120a warms the medium P by warming the transport guide plate 130 itself.

The print heater 120b and the print heater 120c are devices that keep the medium P warm when the liquid coating surface is formed on the medium P. For example, the print heater 120b and the print heater 120c (upper margin + 0.5 ° C., lower margin −0.5 ° C.) are cord heaters embedded in a platen 131 made of an aluminum material. The print heater 120b and the print heater 120c warm the medium P by warming the platen 131 itself.

The post heater 120d and the drying heater 120e are devices for warming the medium P on which the liquid coating surface is formed in order to dry and fix the liquid such as ink. For example, the post heater 120d (upper margin + 2 ° C., lower margin 0 ° C.) is an aluminum foil cord heater. The post heater 120d is attached to the back surface of the transport guide plate 132. The post heater 120d warms the medium P by warming the transport guide plate 132 itself. Further, for example, the drying heater 120e (upper margin + 0.5 ° C., lower margin −0.5 ° C.) is an IR heater. The drying heater 120e radiates IR radiation to the liquid-coated surface of the medium P to dry it. The drying heater 120e may be provided with a fan and may be configured to send hot air to the liquid-coated surface of the medium P.

FIG. 4 is a block diagram showing an example of the function of the control device 101 of FIG. As shown in FIG. 4, the control device 101 has functions as an acquisition unit 101a, a determination unit 101b, and a control unit 101c. In FIG. 3, for the sake of simplicity of explanation, the functions according to the present embodiment are mainly illustrated, but the functions possessed by the control device 101 are not limited to these.

The acquisition unit 101a is a function of acquiring a print instruction from, for example, the operation panel 114. Further, the acquisition unit 101a is a function of acquiring image data (print data) for image formation (printing) via, for example, I / F 107.

The determination unit 101b is a function of determining the white print mode based on the acquired print data and the like. Further, the determination unit 101b includes a function of provisionally determining the print mode.

The control unit 101c is a function of controlling the operation of the image forming apparatus 100 related to printing based on each condition of the determined white printing mode.

A program (hereinafter referred to as a liquid discharge program) for executing the liquid discharge method executed by the image forming apparatus 100 according to the present embodiment is provided by being incorporated in the ROM 103 or the like in advance.

The liquid discharge program executed by the image forming apparatus 100 according to the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile). It may be configured to be recorded and provided on a computer-readable recording medium such as a disk).

Further, the liquid discharge program executed by the image forming apparatus 100 according to the present embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading via the network. .. Further, the liquid discharge program executed by the image forming apparatus 100 according to the present embodiment may be provided or distributed via a network such as the Internet.

The liquid discharge program executed by the image forming apparatus 100 according to the present embodiment has a module configuration including each of the above-mentioned functions (acquisition unit 101a, determination unit 101b, and control unit 101c), and is actually hardware. When the processor (CPU) reads and executes the liquid discharge program from the memory (ROM), each of the above functions is loaded on the main storage device, and the acquisition unit 101a, the determination unit 101b, and the control unit 101c are generated on the main storage device. It is supposed to be done.

The control device 101 according to the present embodiment includes a control device such as a CPU, a storage device such as a ROM or RAM, an external storage device such as an HDD or a CD drive device, a display device such as a display device, a keyboard, or the like. It may have a hardware configuration using an ordinary computer provided with an input device such as a mouse.

A part or all of each function of the control device 101 according to the present embodiment may be realized by an integrated circuit such as an ASIC or a Field Programmable Gate Array (FPGA).

The CPU 102 stores a part or all of the ASIC 106, the print control unit 108, the main scanning motor drive unit 109, the sub-scanning motor drive unit 110, the fan control unit 111, the heater control unit 112, and the I / O 113 in the ROM 103 or the like. It may be configured to realize the desired function by executing the program. Further, a part or all of each of these parts may have a computer configuration including a CPU, ROM, RAM and the like. In this case, each unit realizes a desired function by executing a program stored in a ROM or the like by the CPU. The program executed by the CPU of each part is provided by recording it on a computer-readable recording medium such as a CD-ROM, FD, CD-R, or DVD in an installable format or an executable format file. It may be configured as. Further, the program executed by the CPU of each unit may be stored on a computer connected to a network such as the Internet and provided by downloading via the network. Further, the program executed by the CPU of each part may be configured to be provided or distributed via a network such as the Internet.

Next, an example of the operation of the image forming apparatus 100 according to the present embodiment will be described.

The CPU 102 reads out the print data in the reception buffer of the I / F 107, analyzes the print data, performs necessary image processing, data rearrangement processing, and the like on the ASIC 106, and transfers the print data to the print control unit 108.

The print control unit 108 outputs image data and drive waveforms to the head driver 116 at a required timing. Specifically, the print control unit 108 performs a drive composed of one drive pulse or a plurality of drive pulses by D / A converting and amplifying the pattern data of the drive pulses stored in the ROM 103 and read by the CPU 102. Generate a waveform.

The image data (for example, dot pattern data) for outputting the image may be generated by storing the font data in the ROM 103, for example, or expanding the image data into a bitmap by the printer driver on the host side. It may be transferred to the image forming apparatus 100.

The head driver 116 selectively sends drive pulses constituting a drive waveform given by the print control unit 108 to the pressure generating means of the liquid discharge head 122 based on the input image data (for example, dot pattern data). The liquid discharge head 122 is driven by the application.

Each heater 120 lights up when it wakes up from the sleep mode, and is controlled to a set temperature according to the medium P and the mode. When each heater 120 is turned on, the image forming apparatus 100 is in a state where the liquid coating surface can be formed, and starts the initial operation for forming the liquid coating surface. The drying heater 120e starts lighting when the formation of the liquid coating surface is started. It takes several tens of seconds for the medium P on which the liquid coating surface is formed to be conveyed to the location of the drying heater 120e.

As shown in FIG. 3, the medium P is set on the preheater 120a side. Further, the medium P is conveyed in the direction of arrow B by the transfer roller 123a, the transfer roller 123b, etc. to which the driving force is applied from the sub-scanning motor 118, and the liquid coating surface is formed by discharging the liquid from the liquid discharge head 122. .. For example, as the medium P, PET, PVC, OPP, sheet-shaped media, etc., which are called flexible packaging media, can be used in addition to the roll-type paper.

The medium P sent from the preheater 120a side is first preheated by the preheater 120a to a temperature suitable for forming the liquid coating surface. The preheated medium P is sent by the transfer roller 123a and the transfer roller 123b to the image forming unit 50 in which the liquid discharge head 122 is arranged.

In the image forming unit 50, while the medium P is kept warm by the print heater 120b and the print heater 120c, a liquid such as ink is ejected from the liquid ejection head 122 to form a liquid coating surface. The warmed air rises with the steam, but the fan 119 promotes air convection in order to prevent the upper part of the image forming apparatus 100 from excessively rising in temperature due to its retention.

FIG. 5 is a diagram schematically showing a state in which the carriage 121 of FIG. 2 is viewed from above. As shown in FIG. 5, the medium P (media) is conveyed in the sub-scanning direction (conveyance direction) indicated by the arrow B, and the carriage 121 scans in the direction perpendicular to the moving direction of the medium P to form an image. When forming an image, the number of scans (number of scans) can be changed according to the resolution of the image to be imaged to form a high-resolution image.

For example, if the drive frequency of the head is increased and ink is ejected at a higher frequency with respect to the moving direction (main scanning direction) of the carriage 121 indicated by the arrow A, the resolution in the main scanning direction is increased even at the same moving speed of the carriage 121. Can be done. In addition, by increasing the number of passes at the same location and changing the ejection timing, it is possible to change the landing position of the dots for each pass to increase the resolution. Depending on the resolution to be imaged, the drive frequency may be changed only, or the drive frequency and the number of scans (number of scans) may be combined.

In the moving direction (sub-scanning direction) of the medium P (media) indicated by the arrow B, the resolution can be increased by reducing the feed amount of the medium P. For example, when the nozzle spacing is 300 dpi pitch, 600 dpi can be obtained by forming dots in the next pass between the dots formed in the first pass by performing the interlacing process.

As shown in FIG. 4, the medium P on which the liquid coating surface is formed in the image forming portion 50 is sent further downstream.

The drying heater 120e preheats the filament temperature to a target temperature (to the wavelength of the output electromagnetic wave) by the time the medium P on which the liquid coating surface is formed arrives. After that, when the medium P on which the liquid coating surface is formed arrives, the drying heater 120e lights up in synchronization with the stop timing of the sub-scanning. The lighting timing can be changed depending on the type and mode of the medium P. The reason why the drying heater 120e is not turned on at the same time as the sleep mode is released is to prevent deterioration of the medium P due to unnecessary radiant heating.

The post heater 120d and the drying heater 120e that sends hot air dry and fix a liquid such as ink on the medium P. The medium P that has been dried and fixed is further wound down in a roll shape downstream.

The image forming apparatus 100 according to the present embodiment performs two-layer overlay printing in which the first layer is formed and then the second layer is formed. More specifically, the control device 101 of the image forming apparatus 100 moves the medium P in the direction opposite to the conveying direction after printing the entire range specified by the original in the printing of the first layer, and starts from the same start position. It is formed by overlapping layers.

The control device 101 of the image forming apparatus 100 may form the first layer and the second layer continuously for each scan. Further, the control device 101 of the image forming apparatus 100 may be a method of forming the second layer after completing the first layer for each arbitrary area. The recoating is not limited to two layers, and may be a multi-layer structure having two or more layers.

For example, in the example shown in FIG. 5, process color (black (K), cyan (C), magenta (M), yellow (Y)) inks are arranged on the liquid discharge head 122a and the liquid discharge head 122c, and the liquid discharge head There is also a configuration in which white ink is arranged at 122b. In this case, it is possible to print in layers such as "process color ⇒ white", "white ⇒ process color" or "process color ⇒ white ⇒ process color". Further, for example, if white is printed by the liquid discharge head 122b and then the process color is printed by the liquid discharge head 122c, it is possible to print a color image after undercoating with white.

Hereinafter, an example of a method (white printing mode) in which the control device 101 of the image forming apparatus 100 forms an image with two layers of “white ⇒ process color” will be described.

When printing color ink (liquid ejected later: second liquid) on white ink (liquid ejected first: first liquid), when the white ink is not sufficiently dried, the color ink It may be buried below the white ink. The burial of color ink causes a decrease in density and bleeding, which may lead to a decrease in image quality. Therefore, in order to suppress the burial of the color ink, it is required to improve the dryness of the white ink on the medium (medium P).

Techniques for improving the dryness of ink (liquid) include reducing the amount of white ink injected, stopping the carriage during printing to secure a waiting time for drying, and shortening the nozzle row used for printing. There are methods such as securing a waiting time for drying by doing so.

However, when the amount of white ink applied is reduced, the concealment rate is lowered and the image quality may be lowered. In addition, when the carriage is stopped during printing and when the nozzle row used is shortened, printing cannot be performed during the stop time and the printing width per scan (1 scan) is shortened, so that the printing time is reduced. May increase and productivity may decrease.

Therefore, the image forming apparatus 100 according to the present embodiment is configured so that the number of scans and the amount of ink injected per unit time can be optimized by the control sequence. Specifically, the image forming apparatus 100 does not change the productivity and the total ink ejection amount (total ejection amount), but changes the ink ejection amount (ejection amount) per unit time (for example, one scan). It is configured so that the number of copies can be reduced. Hereinafter, the ink injection amount (ejection amount) per unit time will be referred to as a unit ejection amount.

FIG. 6 is a diagram for explaining an example of the white printing mode realized by the control device 101 of FIG. As shown in FIG. 6, the control device 101 according to the present embodiment modifies the tentatively determined scan condition (discharge condition) of the white print mode, and sets the white print mode in which the number of scans and the unit discharge amount are optimized. decide.

The tentatively determined white printing mode is, for example, configured to print in 12 scans using 178 nozzles for a period of forming a white layer (Wh layer). At this time, it is assumed that the tentatively determined drying period after the white printing is 18.5 scans. The color layer is printed after drying.

On the other hand, the white print mode optimized by the control device 101 according to the present embodiment is, for example, a unit discharge amount from the tentatively determined white print mode by printing with 18 scans using 267 nozzles for the Wh layer. Is a small configuration. Specifically, in the optimized white printing mode, in the first 6 scans (first period), white ink is ejected at the unit ejection amount (first unit ejection amount) as tentatively determined, and then the next 6 scans are performed. In the scan (second period), white ink is struck with half the unit discharge amount (second unit discharge amount) of the tentative decision, and an additional 6 scans (second period) are used to compensate for the reduced total discharge amount. ) Is used to hit white ink with a unit discharge amount (second unit discharge amount) that is half of the tentative determination.

The color layer printing and feed amount (for example, 14.833 nozzles) are not changed between the tentatively determined white printing mode and the optimized white printing mode.

As described above, the optimized white print mode does not increase the total discharge amount or the resolution even when the number of scans of the Wh layer is increased from the tentatively determined white print mode. With this configuration, the ink injection amount (ejection amount) per unit time (1 scan) can be partially reduced without changing the productivity and the total ink injection amount (total ejection amount).

7-1 and 7-2 are diagrams for explaining the improvement of dryness by the white printing mode of FIG. 7. 7-1 and 7-2 show a case where the unit discharge amount is large and a case where the unit discharge amount is small by increasing the number of scans, respectively. As shown in FIG. 7-1, when the unit discharge amount is large, the heat Q from the heater 120 is sufficient and the heat Q from the heater 120 is sufficiently applied to the entire discharged white ink Wh0 (liquid) depending on the length of the drying period. It may not be transmitted evenly. On the other hand, as shown in FIG. 7-2, when the white ink Wh is injected in a plurality of times with a small discharge amount, the water content of the white ink Wh1 that has been applied earlier rises to form a thin layer. , The next white ink Who2 will be driven. Since the water content of the white ink Wh1 ejected earlier has already evaporated, the heat Q from the heater 120 is easily transferred to the white ink Wh2 that is ejected later.

As described above, according to the white printing mode according to the present embodiment, the ink is dried by reducing the ink ejection amount per unit time without changing the total ejection amount of the white ink Wh (liquid) and the printing time. The sex can be improved.

FIG. 8 is a flowchart showing an example of a flow of determining the white print mode executed by the control device 101 of FIG.

In step S101, the acquisition unit 101a realized by the control device 101 acquires a print instruction. The print instruction is generated according to, for example, the operation result of the operation panel 114 of the user. In addition, the acquisition unit 101a acquires print data (image data) and various data associated therewith.

In step S102, the determination unit 101b realized by the control device 101 tentatively determines the mode (white printing mode) at the time of white printing. Specifically, the determination unit 101b tentatively determines the number of scans (n) at the time of white printing, the number of blank scans (a) after white printing, and the unit discharge amount (m). Here, the tentatively determined white printing mode can be expressed as a discharge condition relating to a case where a predetermined total discharge amount of liquid is discharged with a constant unit discharge amount over the entire period. Also, the number of empty scans corresponds to the length of the drying period.

In step S103, the determination unit 101b determines the minimum number of blank scans (a') required after white printing. The minimum number of blank scans (a') is determined from the viewpoint of obtaining the dryness required for the white printed portion. Specifically, the minimum number of empty scans (a') is the total amount of white ink adhered (total discharge amount, m × n), the number of scans in the tentatively determined white print mode (n), the heater temperature, and the media. It is determined by the type of (medium P) and the head configuration of the liquid discharge head 122 (restrictions on the head configuration capable of printing white). It is assumed that the minimum number of empty scans (a') required for each condition has been verified and confirmed in advance. The minimum number of empty scans (a') required for each predetermined condition may be stored in the ROM 103 or the like in the form of a table, for example. In this case, the determination unit 101b determines the minimum number of empty scans (a') by referring to the table according to the conditions.

In step S104, the determination unit 101b compares the number of temporary blank scans (a) after white printing with the minimum number of blank scans (a ′). Specifically, the determination unit 101b determines whether or not the number of temporary blank scans (a) after white printing is larger than the minimum number of blank scans (a') (a> a'). The process proceeds to step S106 if it is determined that a> a', and proceeds to step S105 if it is not determined.

In step S105, the determination unit 101b determines the white print mode from each of the provisionally determined conditions. This determination is based on the fact that a ≦ a ′, and there is no room for further increasing the number of scans. After that, the process proceeds to step S107.

In step S106, the determination unit 101b corrects the tentatively determined white print mode (discharge condition). This decision is based on the fact that a> a'and there is still room to increase the total number of white print scans by a-a' scans.

Specifically, the determination unit 101b increases the number of scans to the limit and determines the number of scans (n'= n + (a-a')) at the time of white printing.

Further, the determination unit 101b determines the minimum number of blank scans (a') as the number of blank scans after white printing.

Further, the determination unit 101b determines the unit discharge amount (m') in the added aa'scan to a value smaller than the tentatively determined unit discharge amount (m). Further, the determination unit 101b tentatively determines the unit ejection amount in the final aa'scan of the n scans so as not to change the total adhesion amount (total ejection amount) of the white ink. Determine a value smaller than the quantity (m). In the example shown in FIG. 6, the unit discharge amount (first unit discharge amount) of the period (first period) of the 1st to {n- (a-a')} scans is m, respectively, and {n. -(A-a') + 1} to {n + (a-a')} The unit discharge amount (second unit discharge amount) of the scan eye period (second period) is a tentatively determined unit. It is m / 2, which is half of the discharge amount (m).

In step S107, the control unit 101c realized by the control device 101 starts printing. Specifically, the control unit 101c controls the operation of the liquid discharge head 122 and the like based on each condition of the determined white print mode. After that, in step S108, the control unit 101c ends the process related to printing.

In the present embodiment, the case where the unit discharge amount (adhesion amount per scan) at the time of the additional scan is set to half of the tentatively determined unit discharge amount has been described as an example, but the present invention is not limited to this. .. For example, the ratio of the unit discharge amount in the second period (second unit discharge amount) to the unit discharge amount in the first period (first unit discharge amount) is the difference between the lengths of the two drying periods (the difference between the lengths of the two drying periods). The discharge conditions may be determined so as to be equal to the ratio of a-a') to the length of the second period.

Further, in the present embodiment, there are two periods, a period of the tentatively determined unit discharge amount (first period) and a period of the unit discharge amount smaller than the tentatively determined unit discharge amount (second period). The case where it is set has been described as an example, but the present invention is not limited to this. For example, the second period may be further divided, and for each of the three or more periods, three or more unit discharge amounts may be set so as to gradually decrease. For example, the unit discharge amount of the additional scan (fourth period) is made smaller than m / 2, and the unit discharge amount of the last a-a'scan (third period) of the n scans is made less than m / 2. It may be configured to be enlarged.

In the present embodiment, the case where the tentatively determined white print mode is modified has been described as an example, but the present invention is not limited to this. Based on the minimum number of blank scans (a') and the like, the white print mode may be determined in a variable unit discharge amount without tentatively determining the white print mode.

As described above, the image forming apparatus 100 according to the present embodiment is configured so that the number of scans and the amount of ink injected per unit time (for example, one scan) can be optimized by the control sequence. Specifically, the image forming apparatus 100 can partially reduce the ink injection amount (ejection amount) per unit time without changing the productivity and the total ink injection amount (total ejection amount). It is configured. More specifically, the image forming apparatus 100 discharges a predetermined total discharge amount of liquid per unit time (unit discharge amount) by scanning a plurality of times and transporting the medium P (recording medium) a plurality of times. It is a device that discharges onto the medium P. In the image forming apparatus 100, the determination unit 101b realized by the control device 101 has a first unit discharge amount in which the second unit discharge amount is smaller than the first unit discharge amount and the total number of scans is a predetermined total discharge amount. The discharge conditions for discharging a predetermined total discharge amount of liquid are determined so as to be larger than the number divided by. Here, the scanning period indicating the period corresponding to the plurality of scanning includes the first period and the second period after the first period. The first unit discharge amount indicates the unit discharge amount in the first period. The second unit discharge amount indicates the unit discharge amount in the second period. According to this configuration, the burial of color ink can be suppressed by reducing the ejection amount of white ink per unit time without changing the total ejection amount of white ink and the printing time. That is, according to the technique according to the present embodiment, it is possible to improve the dryness of the discharged liquid without deteriorating the quality and productivity of the product formed by discharging the liquid.

(Second Embodiment)
Next, the image forming apparatus 100 (liquid ejection apparatus) according to the second embodiment will be described. The description of the parts common to the first embodiment described above will be omitted as appropriate.

The image forming apparatus 100 according to the present embodiment and the image forming apparatus 100 according to the first embodiment have different white print mode configurations. FIG. 9 is a diagram for explaining another example of the white printing mode realized by the control device 101 of FIG.

In the example shown in FIG. 9, the tentatively determined white printing mode includes a white printing period of 16 scans, a drying period of 10 scans, and a color printing period of 16 scans. The control device 101 according to the present embodiment corrects the white printing period of 16 scans to the white printing period of 20 scans. In this case, for example, the control device 101 does not change the unit discharge amount in the first 12 scans, and halves the tentatively determined unit discharge amount in the remaining 8 scans.

Even with such a configuration, the drying property can be improved without changing the total adhesion amount (total discharge amount) as in the above-described embodiment.

(Third Embodiment)
Next, the image forming apparatus 100 (liquid ejection apparatus) according to the third embodiment will be described. The description of the parts common to the first embodiment described above will be omitted as appropriate.

The image forming apparatus 100 according to the present embodiment further includes a detecting unit configured to detect the image density on the medium P. As the detection unit, for example, a color measurement camera (imaging device) for performing color measurement on a detection pattern formed on the medium P can be applied. The colorimetric camera is supported by, for example, a carriage 121. Depending on the ink color used for the detection pattern, a camera (imaging device) configured to be able to measure the luminance value of a single color may be used as the detection unit.

The detection pattern is formed by printing a process color image on white. That is, the printing of the detection pattern is performed by ejecting white ink (first liquid) on the medium P and then ejecting color ink (second liquid) on the ejected white ink. It is said. The tentatively determined white print mode conditions are used for the unit ejection amount of each ink in printing the detection pattern. The image density on the medium P can be expressed as a characteristic value related to embedding that changes with the embedding of the color ink in the white ink. Similarly, the detection unit can be described as a sensor that detects the embedding of color ink in white ink.

The colorimetric camera moves on the medium P on which the detection pattern is formed by transporting the medium P and / or moving the carriage 121, and captures an image when it comes to a position facing the detection pattern.

The acquisition unit 101a realized by the control device 101 according to the present embodiment further includes a function of acquiring RGB values (characteristic values related to burial) of the detection pattern obtained by imaging. Further, the determination unit 101b further includes a function of calculating the distribution of the image density (characteristic value regarding burial) regarding the detection pattern based on the RGB value of the acquired detection pattern. Further, the determination unit 101b includes a function of determining the degree of embedding of the color ink in the white ink based on the characteristic value related to the embedding and, for example, a predetermined threshold value set in advance in the ROM 103. When a monochromatic image is used as the process color image, a distribution of luminance values related to the detection pattern can be used as the distribution of the image density related to the detection pattern.

Hereinafter, the flow of determining the white print mode according to the present embodiment will be described by taking as an example a case where a pattern in which a black patch is printed on white is used as the detection pattern. FIG. 10 is a flowchart showing another example of the flow of determining the white print mode realized by the control device 101 of FIG.

Step S201 and step S202 are the same as step S101 and step S102 in FIG. 8, respectively. The process proceeds to step S203 after tentatively determining the white print mode.

In step S203, the control unit 101c realized by the control device 101 prints the detection pattern according to each condition of the tentatively determined white print mode.

In step S204, the acquisition unit 101a realized by the control device 101 acquires the RGB values related to the detection pattern from the detection unit. The determination unit 101b realized by the control device 101 calculates the distribution of the luminance values related to the detection pattern based on the calculated RGB values. Further, the determination unit 101b determines whether or not the image density (luminance value) related to the detection pattern is equal to or higher than a predetermined threshold value. That is, the determination unit 101b determines the degree of burial based on the characteristic value related to burial. The process proceeds to step S206 if it is determined that the image density (luminance value) related to the detection pattern is equal to or higher than a predetermined threshold value, and proceeds to step S205 if it is not determined.

Steps S205 to S209 are the same as steps S104 to S108 of FIG. 8, respectively.

11-1 and 11-2 are diagrams for explaining the detection of the image density by the sensor (detection unit), which is carried out in the flow of determining the white print mode of FIG. In the example shown in FIG. 11-1, the image density (luminance value) related to the detection pattern is 255, which exceeds 240, which is a value set as a threshold value. Therefore, the degree of burial is small (the degree of burial does not exceed the standard), and it is not necessary to modify the white print mode. On the other hand, in the example shown in FIG. 11-1, the image density (luminance value) related to the detection pattern is 230, which is lower than the value 240 set as the threshold value. In this way, when it is not determined that the image density (luminance value) related to the detection pattern is equal to or higher than a predetermined threshold value, the black ink is not allowed to be buried in the white ink (the degree of burial exceeds the standard). The flow is to correct the tentatively determined white print mode.

In this way, the image forming apparatus 100 according to the present embodiment prints the detection pattern after tentatively determining the white print mode, reads the density of the printed detection pattern (characteristic value related to burial), and colors. The embedding (image quality) of the ink (the liquid ejected later) in the white ink (the liquid ejected earlier) is determined. When the image quality has achieved the target level, the image forming apparatus 100 makes the final determination in the provisional determination mode, and when the image quality is not achieved, the white printing mode is corrected. That is, even if there is a margin in the drying period, the white printing mode is not corrected if the image quality achieves the target level. According to this configuration, the same effect as that of the above-described embodiment can be obtained without unnecessarily increasing the number of scans. That is, according to the present technology, it is possible to further obtain the effect of suppressing failure and wear due to an increase in the number of unnecessary scans.

As the image density (luminance value) related to the detection pattern, a value at an arbitrary point may be used, or a minimum value or an average of values at a plurality of points (for example, a point on an arbitrary straight line or a point in a region). Values, median values, etc. may be used. Further, the determination of the image density (luminance value) regarding the detection pattern may be performed for each color, for example, according to the ink color used for the detection pattern.

The camera (imaging device) as the detection unit may have a reference chart configured to be imaged together with the detection pattern. In this case, the determination in step S204 may be performed with respect to the difference from the reference chart.

The case where the determination regarding the ink burial is performed based on the image density has been described as an example, but the present invention is not limited to this. The determination regarding the burial of the ink may be performed as long as it is a method capable of determining the image quality of the detection pattern, and may be performed based on, for example, the surface roughness (characteristic value regarding burial) of the detection pattern. In this case, as the detection unit, a distance measuring sensor or the like configured to be able to measure the surface roughness of the detection pattern may be used. For example, when the measured surface roughness is large, it is determined that the degree of burial is large.

The technique according to the present embodiment can be combined with the technique according to the second embodiment.

In the above embodiment, the case where the total discharge amount does not change when the tentatively determined white print mode is corrected has been described as an example, but the present invention is not limited to this. That is, it is not necessary to keep the total discharge amount strictly constant when modifying the white print mode, and the total discharge amount may be increased or decreased as long as the image quality is not affected.

In the above embodiment, for example, as shown in FIG. 5, the medium P is conveyed in the sub-scanning direction (conveyance direction) indicated by the arrow B by driving the sub-scanning motor 118, and is in a direction perpendicular to the moving direction of the medium P. The case where the carriage 121 scans and an image is formed has been described as an example, but the present invention is not limited to this. For example, the sub-scanning motor 118 driven by the control of the sub-scanning motor driving unit 110 may move the liquid discharge head 122 in the sub-scanning direction. In this case, the image forming apparatus 100 performs a predetermined total discharge amount of liquid by scanning the liquid discharge head 122 in the main scanning direction a plurality of times and moving the liquid discharge head 122 in the sub-scanning direction a plurality of times. It can be expressed as an example of a liquid discharge device that discharges a unit discharge amount, which is a discharge amount per unit time, onto the medium P. Therefore, the image forming apparatus 100 according to the above embodiment includes a liquid discharge head 122 for discharging the liquid to the medium P, a main scanning moving mechanism for moving the liquid discharge head 122 in the main scanning direction, and the medium P or the liquid discharge head 122. The liquid discharge head 122 is scanned in the main scanning direction a plurality of times, and the medium P or the liquid discharge head 122 is moved in the sub scanning direction a plurality of times. It can be expressed as an example of a liquid discharge device that discharges a predetermined total discharge amount of liquid onto the medium P in units of unit discharge amounts, which is the discharge amount per unit time. Here, the main scanning movement mechanism includes, for example, the main scanning motor 117 and / or the main scanning motor driving unit 109. Further, the sub-scanning movement mechanism includes, for example, the sub-scanning motor 118 and / or the sub-scanning motor driving unit 110. The sub-scanning movement mechanism may move the medium P in the sub-scanning direction and may move the liquid discharge head 122 in the sub-scanning direction.

In the above embodiment, an example in which the image forming apparatus as the liquid ejection device of the present invention is applied to a copying machine has been described, but at least two functions of a copy function, a printer function, a scanner function, and a facsimile function are provided. It can be applied to any image forming apparatus such as a multifunction device, a printer, a scanner apparatus, and a facsimile apparatus.

In the present application, the "liquid discharge device" is a device including a liquid discharge head or a liquid discharge unit, which drives the liquid discharge head to discharge the liquid. The liquid discharge device includes not only a device capable of discharging a liquid to a device to which the liquid can adhere, but also a device for discharging the liquid toward the air or the liquid.

This "liquid discharge device" can also include a device for feeding, transporting, and discharging paper to which a liquid can adhere, a pretreatment device, a posttreatment device, and the like.

For example, as a "liquid ejection device", powder is formed in layers in order to form an image forming apparatus, which is an apparatus for ejecting ink to form an image on paper, and a three-dimensional model (three-dimensional model). There is a three-dimensional modeling device (three-dimensional modeling device) that discharges a modeling liquid into a powder layer.

Further, the "liquid discharge device" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. The "liquid discharge device" includes, for example, a device for forming a pattern or the like having no meaning in itself and a device for forming a three-dimensional image.

The above-mentioned "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates. As a specific example, "materials to which a liquid can adhere" include recording media such as paper, recording paper, recording paper, film, and cloth, electronic substrates, electronic components such as piezoelectric elements, and powder layers (powder layers). It is a medium such as an organ model or a test cell, and includes all substances to which a liquid adheres unless otherwise specified.

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached even temporarily.

Further, the above-mentioned "liquid" may have a viscosity and surface tension that can be discharged from the liquid discharge head. Although not particularly limited, the "liquid" preferably has a viscosity of 30 mPa · s or less at room temperature / normal pressure or by heating / cooling. More specifically, "liquid" refers to solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, DNA, amino acids and proteins, and calcium. Solvents, suspensions, emulsions, etc. containing biocompatible materials such as natural pigments, edible materials such as natural pigments, etc. It can be used as a liquid for forming a circuit resist pattern, a liquid for forming a three-dimensional molding, and the like.

Further, the "liquid discharge device" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition to the above, the "liquid ejection device" includes a treatment liquid coating device that ejects the treatment liquid onto the paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper. There is an injection granulator that granulates fine particles of the raw material by injecting a composition liquid in which the raw material is dispersed in a solution through a nozzle.

1 Cartridge loading part 10 (10k, 10c, 10m, 10y) Ink cartridge 21A, 21B Side plate 31 Main guide rod 32 Sub sheet metal guide 36 Supply tube 37 Optical sensor 50 Image forming part 81 Maintenance / recovery mechanism 82 (82a, 82b, 82c) Cap 83 Wiping unit 100 Image forming device (liquid discharge device)
100a Device body 101 Control device 101a Acquisition unit 101b Determination unit 101c Control unit 102 CPU
103 ROM
104 RAM
105 Non-volatile memory (NVRAM)
106 ASIC
107 I / F
108 Print control unit 109 Main scanning motor drive unit 110 Sub-scanning motor drive unit 111 Fan control unit 112 Heater control unit 113 I / O
114 Operation panel 115 Environmental sensor 116 Head driver 117 Main scanning motor 118 Sub scanning motor 119 Fan 120 Heater 120a Preheater 120b, 120c Print heater 120d Post heater 120e Drying heater 121 Carrying 122 (122a, 122b, 122c) Liquid discharge head 123 (123a) , 123b) Conveying roller 130, 132 Conveying guide plate 131 Platen P medium (recording medium)
Wh (Wh0, Wh1, Wh2) White ink

Japanese Unexamined Patent Publication No. 2011-73177

Claims (11)

A liquid discharge head that discharges a liquid to a recording medium, a main scan movement mechanism that moves the liquid discharge head in the main scanning direction, and a sub-scanning movement mechanism that moves the recording medium or the liquid discharge head in the sub-scanning direction. A liquid discharge device that discharges a predetermined total discharge amount of liquid onto the recording medium by a unit discharge amount, which is a discharge amount per unit time, by performing a plurality of scans and moving in a plurality of sub-scan directions. And
The scanning period indicating the period corresponding to the plurality of scans includes the first period and the second period after the first period, and the second unit discharge indicating the unit discharge amount in the second period. The amount is less than the first unit discharge amount indicating the unit discharge amount in the first period, and the number of scans of the plurality of scans is the predetermined total discharge amount divided by the first unit discharge amount. A liquid discharge device including a determination unit for determining discharge conditions for discharging the liquid having the predetermined total discharge amount so as to be larger than the number. The decision unit
The number of scans, the unit discharge amount, and the drying period after the liquid of the predetermined total discharge amount is discharged in the case of discharging the liquid of the predetermined total discharge amount with a constant unit discharge amount over the entire period. Tentatively determine the discharge conditions including the length of
When the length of the drying period included in the tentatively determined discharge condition is longer than the minimum length of the drying period required for drying the liquid discharged under the tentatively determined discharge condition, the tentatively determined discharge condition Is modified so that the second unit discharge amount is smaller than the first unit discharge amount, and the number of scans is larger than the number obtained by dividing the predetermined total discharge amount by the first unit discharge amount. To determine the discharge conditions for discharging the liquid of the predetermined total discharge amount.
The liquid discharge device according to claim 1. The liquid discharge device according to claim 2, wherein the determination unit does not change the predetermined total discharge amount in the modification of the discharge conditions. In the determination unit, the ratio of the second unit discharge amount to the first unit discharge amount is equal to the ratio of the difference between the lengths of the two drying periods and the length of the second period. The liquid discharge device according to claim 2 or 3, wherein the discharge conditions are modified. The liquid discharge device is a liquid discharge device provided with a detection unit for detecting the burial of a second liquid discharged after the first liquid in the first liquid discharged earlier.
By discharging the first liquid onto the recording medium under the tentatively determined discharge conditions and then discharging the second liquid onto the first liquid, at least the second liquid is discharged onto the recording medium. A control unit that forms a two-layer detection pattern,
Further provided with an acquisition unit for acquiring the characteristic value related to the burial in the detection pattern.
The determination unit determines the degree of burial in the detection pattern based on the characteristic value related to the burial, and when it is determined that the degree of burial exceeds a predetermined standard, the tentatively determined first. Correct the discharge condition for the liquid of 1.
The liquid discharge device according to any one of claims 2 to 4. The detection unit is an imaging device that detects an image density on the recording medium that changes with the burial.
The characteristic value relating to the burial includes the brightness value of each pixel obtained by the imaging device.
The liquid discharge device according to claim 5. The liquid discharge device according to any one of claims 1 to 6, wherein the unit discharge amount is a discharge amount per scan. The liquid discharge device according to any one of claims 1 to 7, wherein the unit discharge amount is constant in the first period. The second period is a third period of a third unit discharge amount less than the first unit discharge amount, and a fourth unit less than the third unit discharge amount after the third period. The liquid discharge device according to any one of claims 1 to 8, which includes a fourth period of the discharge amount. A liquid discharge head that discharges a liquid to a recording medium, a main scanning movement mechanism that moves the liquid discharge head in the main scanning direction, and a sub-scanning moving mechanism that moves the recording medium or the liquid discharge head in the sub-scanning direction. A liquid discharge device that discharges a predetermined total discharge amount of liquid onto the recording medium by a unit discharge amount, which is a discharge amount per unit time, by performing a plurality of scans and a plurality of movements in the sub-scan direction. In
The scanning period indicating the period corresponding to the plurality of scans includes the first period and the second period after the first period, and the second unit discharge indicating the unit discharge amount in the second period. The amount is less than the first unit discharge amount indicating the unit discharge amount in the first period, and the number of scans of the plurality of scans is the predetermined total discharge amount divided by the first unit discharge amount. A liquid discharge method including a step of determining a discharge condition for discharging the liquid having the predetermined total discharge amount so as to be larger than the number. A liquid discharge head that discharges a liquid to a recording medium, a main scanning movement mechanism that moves the liquid discharge head in the main scanning direction, and a sub-scanning moving mechanism that moves the recording medium or the liquid discharge head in the sub-scanning direction. A liquid discharge device that discharges a predetermined total discharge amount of liquid onto the recording medium by a unit discharge amount, which is a discharge amount per unit time, by performing a plurality of scans and moving in a plurality of sub-scanning directions. On a computer implemented in
The scanning period indicating the period corresponding to the plurality of scans includes the first period and the second period after the first period, and the second unit discharge indicating the unit discharge amount in the second period. The amount is less than the first unit discharge amount indicating the unit discharge amount in the first period, and the number of scans of the plurality of scans is the predetermined total discharge amount divided by the first unit discharge amount. A program for executing a step of determining a discharge condition for discharging a liquid having a predetermined total discharge amount so as to be larger than the number.

Images