JP7567305B2 - LIQUID DISCHARGE APPARATUS, LIQUID DISCHARGE METHOD, AND LIQUID DISCHARGE PROGRAM - Google Patents

Description

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

In conventional inkjet printing devices, a preheater, print heater, and post heater are installed on the media transport guide plate from the paper feed roll to the paper discharge roll, and printing and drying are performed while heating the media.

An infrared heater is placed in a non-contact manner on the media transport surface side of the paper discharge guide plate of the media transport guide plate, and the heat from the infrared heater is used by a fan to dry the ink on the media surface in order to achieve high productivity. In this way, the configuration consisting of a far-infrared heater, a fan, and a reflector that directs the radiant heat of the far-infrared heater toward the media surface so as to cover the paper discharge guide plate is called a drying unit.

The media is heated in the drying unit, and the ink lands on the platen, and when the media is heated to the desired temperature, the dots spread to the desired size and form an image. There is a technology in which the media with the image formed is transported through the drying unit to remove the moisture from the ink on the media and dry it.

Patent Document 1 discloses a configuration for providing a drying device that shortens the time required to heat the heater and starts recording on the recording medium early, in which the blowing of air by the blowing means is stopped during the heating period in which the heater is heated, preventing the heating rate of the heater from decreasing due to the wind hitting the heater, and shortening the heating period to start recording on the recording medium early.

However, in Patent Document 1, during the heating period when the heater is heated, the blowing of air by the blowing means can be stopped and recording of the recording material on the recording medium can be started early, but in the highly productive transport mode, there is a problem that the amount of heat provided by the heater that heats the recording medium from the back side of the recording surface alone is insufficient, resulting in poor fixing.

In addition, the ink used in conventional inkjet printing devices can experience an increase in temperature near the nozzles in the inkjet head due to radiant heat from the drying unit. When the ink temperature rises, the ink thickens and may adhere to the area near the nozzles, resulting in poor ejection. For this reason, there is a demand for ink that can be ejected normally without increasing ink viscosity even when the temperature rises.

The present invention aims to provide a liquid ejection device that can quickly bring the temperature inside the drying unit to a preset temperature, prevent poor fixation of ink on the media even in a highly productive transport mode, and suppress ejection defects.

In order to solve the above problem, a liquid ejection device of the present invention is a liquid ejection device comprising: a heater that heats a medium on which liquid has landed; a print data receiving unit that receives print data; a print mode discrimination unit that discriminates a print mode based on the received print data; a first heating control unit that heats with the heater until a preset temperature is reached and starts printing after the end of the heating period; a second heating control unit that starts printing without an intervening heating period; and a heating control selection unit that selects heating control by either the first heating control unit or the second heating control unit based on the print mode discriminated by the print mode discrimination unit , wherein the liquid is an ink-jet ink containing 10% by mass or more of an alcohol-based solvent having a boiling point of 180° C. or higher at one atmospheric pressure, with respect to the total amount of the liquid, and the heating control selection unit selects a heating control pattern by the first heating control unit when the print mode discrimination unit discriminates the print mode as a temperature higher than the preset temperature, and selects a heating control pattern by the second heating control unit when the print mode discrimination unit discriminates the print mode as a temperature lower than the preset temperature.

According to the present invention, the temperature inside the drying unit can be quickly raised to a preset temperature, preventing poor fixation of ink on the media even in the highly productive transport mode, and suppressing ejection defects.

FIG. 1 is a diagram illustrating an example of a main configuration of an inkjet recording apparatus. FIG. 1 illustrates an example of a hardware configuration of an inkjet recording apparatus. FIG. 2 is a diagram illustrating an example of a functional block configuration of a CPU. FIG. 11 is a diagram showing an example of operation timing of the drying unit by the first heating control unit. 11 is a diagram showing an example of operation timing of the drying unit by a second heating control unit. FIG. 6 is a flowchart showing an example of a medium drying process of the inkjet recording apparatus. 10 is a flowchart of a subroutine illustrating an example of a heating control determination process based on a conveying speed. 10 is a flowchart of a subroutine illustrating an example of a heating control determination process based on a heating temperature. FIG. 1 illustrates an example of a recording device. FIG. 2 is a diagram showing an example of a main tank.

The liquid ejection device, liquid ejection method, and liquid ejection program according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the embodiments shown below, and can be modified within the scope of what a person skilled in the art can imagine, including other embodiments, additions, modifications, deletions, etc., and any aspect is within the scope of the present invention as long as it achieves the functions and effects of the present invention.

The liquid ejection device of the present invention is a liquid ejection device that includes a heater that heats the medium on which the liquid has landed, a print data receiving unit that receives print data, a print mode discrimination unit that discriminates the print mode based on the received print data, a first heating control unit that heats with the heater until a preset temperature is reached and starts printing after the end of the heating period, a second heating control unit that starts printing without the heating period, and a heating control selection unit that selects either the heating control of the first heating control unit or the second heating control unit based on the print mode discriminated by the print mode discrimination unit, and is characterized in that the liquid is an inkjet ink that contains 10% by mass or more of an alcohol-based solvent with a boiling point of 180°C or higher at 1 atmospheric pressure relative to the total amount of the liquid.

(Configuration of Inkjet Recording Apparatus)
An embodiment of a liquid ejection apparatus according to the present invention will be described below by taking an inkjet recording apparatus as an example of the liquid ejection apparatus.

Figure 1 is a diagram showing an example of the main configuration of an inkjet recording device according to this embodiment. The main configuration of an inkjet recording device 10 according to this embodiment will be described with reference to Figure 1. Note that in this embodiment, the inkjet recording device 10 shown in Figure 1 will be described as a serial type inkjet recording device (an example of a liquid ejection device), but it can also be applied to a line type.

As shown in FIG. 1, the inkjet recording device 10 according to this embodiment is equipped with a roll media storage section 12 in which media (recording medium) 17 is wound around a cylindrical core, and a take-up roll 13. In FIG. 1, the media 17 is in contact with the feed guide plate 15, platen 23, and discharge guide plate 16 on each of the heaters 31 to 33 with the recording surface facing up, and is transported onto the feed guide plate 15, platen 23, and discharge guide plate 16. The take-up roll 13 is a discharge means on which the media 17 on which an image has been formed (printed) is wound for collection. The platen 23, roll media storage section 12, and take-up roll 13 are arranged so that the media 17 travels from the roll media storage section 12 through the platen 23 to the take-up roll 13.

Each heater 31 to 33 is formed in a film shape, with the preheater 32 being disposed on the rear side of the paper feed guide plate 15, the print heater 31 being disposed on the rear side of the platen 23, and the post heater 33 being disposed on the rear side of the paper discharge guide plate 16, and arranged in the order of preheater 32, print heater 31, and post heater 33 from the conveying direction indicated by the white arrow F.

The infrared heater support member 30a is provided at a position facing the paper discharge guide plate 16, and the two infrared heaters 30 are positioned so that they face the paper discharge guide plate 16 with both ends of the infrared heater 30 supported (not shown).

The drying unit 18 is an area surrounded by the paper discharge guide plate 16 and the exterior cover, and is composed of an infrared heater 30 supported by an infrared heater support member 30a, and a hot air fan 34 located upstream in the transport direction. In the drying unit 18, the infrared heater 30 is provided in a position opposite the post heater 33, and the wind blown from the hot air fan 34 provided upstream in the transport direction hits the post heater 33 and the infrared heater 30, and the wind heated by the post heater 33 and the infrared heater 30 dries the ink attached to the media 17.

As shown in FIG. 1, the carriage 21 is arranged to face the platen 23 and the print heater 31. The nozzles of the recording head 22 attached to the carriage 21 correspond to the platen 23 and the print heater 31. This allows ink to be ejected from the nozzles of the recording head 22 onto the recording surface of the medium 17 transported above the platen 23, recording dots on the recording surface. In addition, by causing the recording head 22 to perform a main scan in the main scanning direction (depth direction in the drawing) together with the carriage 21 while ejecting ink, a row of dots can be recorded in the main scanning direction on the medium 17.

As shown in FIG. 1, the conveying section 14 is provided with a driven pressure roller 14b facing the driving feed roller 14a at a predetermined position upstream of the platen 23 in the conveying direction. The feed roller 14a and the pressure roller 14b are formed in a cylindrical shape, and their axial direction coincides with the core of the roll media storage section 12. The media 17 is sandwiched between the feed roller 14a and the pressure roller 14b.

Then, as the feed roller 14a rotates, the media 17 is transported over the paper feed guide plate 15, the platen 23, and the paper discharge guide plate 16. Furthermore, by performing main scanning of the carriage 21 and transporting the media 17, ink dots are recorded in two-dimensional directions on the recording surface of the media 17, forming a print image.

By driving the feed roller 14a, the media 17, on which ink dots are recorded on the recording surface, is transported onto the post heater 33 and the paper discharge guide plate 16. This allows the air sent from the hot air fan 34 to be heated by the post heater 33 and the infrared heater 30 and blown onto the recording surface of the media 17 transported onto the paper discharge guide plate 16. In other words, the heating from the back side of the media 17 and the blowing of air from the recording surface can promote the drying of the ink dots recorded on the recording surface.

Because the media 17 is heated in advance by the preheater 32 and the print heater 31 before it reaches the paper discharge guide plate 16, the ink dots can be dried immediately after landing.

The preheater temperature sensor 72, print heater temperature sensor 71, and post heater temperature sensor 73 measure the temperatures of the preheater 32, print heater 31, and post heater 33, respectively. The infrared heater temperature sensor 70 is attached to the infrared heater support member 30a and measures the temperature at a position away from the infrared heater 30 without contact. The media surface temperature sensor 74 is attached to the infrared heater support member 30a and measures the temperature of the surface of the media 17 on the paper discharge guide plate 16. The preheater 32, print heater 31, and post heater 33 are controlled so that the temperatures measured by the preheater temperature sensor 72, print heater temperature sensor 71, and post heater temperature sensor 73, respectively, become the set temperature. The infrared heater 30 is controlled so that the temperature of the surface of the media 17 measured by the media surface temperature sensor 74 becomes the set temperature.

(Hardware configuration of the inkjet recording device)
2 is a diagram showing an example of the hardware configuration of an inkjet recording apparatus according to this embodiment. The hardware configuration of the inkjet recording apparatus 10 according to this embodiment will be described with reference to this FIG.

As shown in FIG. 2, the inkjet recording device 10 according to this embodiment includes a control unit 50, a hot air fan 34, an infrared heater 30, a print heater 31, a pre-heater 32, a post-heater 33, the various temperature sensors 70 to 74 described above, a carriage 21, a recording head 22, a main scanning motor 75, a media transport motor 76, an operation panel 160, and a storage 170.

The control unit 50 is a device that controls the operation of the entire inkjet recording device 10. As shown in FIG. 2, the control unit 50 includes a CPU (Central Processing Unit) 51, a ROM (Read Only Memory) 52, a RAM (Random Access Memory) 53, an ASIC (Application Specific Integrated Circuit) 54, an I/O 55, a host I/F 56, a hot air fan control unit 65, a heater control unit 64, a head drive control unit 61, a main scanning motor drive unit 62, and a transport motor drive unit 63.

The CPU 51 is a calculation device that controls the overall operation of the inkjet recording device 10. The ROM 52 is a non-volatile memory that retains data and programs even when the power to the inkjet recording device 10 is cut off. The RAM 53 is a volatile memory that functions as a work area for the CPU 51.

The ASIC 54 is an integrated circuit that processes various signals on image data or print data, performs image processing such as sorting, and processes input/output signals for controlling the entire inkjet recording device 10.

The I/O 55 is an interface that inputs detection signals from various temperature sensors 70-74. The host I/F 56 is an interface that transmits and receives data (print data, etc.) and signals to and from the host 150. The host I/F 56 is, for example, a network interface that complies with TCP (Transmission Control Protocol)/IP (Internet Protocol). The host I/F 56 may also be an interface such as USB (Universal Serial Bus). Examples of the host 150 connected to the host I/F 56 include an information processing device such as a PC (Personal Computer), an image reading device such as an image scanner, or an imaging device such as a digital camera.

The head drive control unit 61 drives and controls the recording head 22. The head drive control unit 61 transfers image data (processed data, ejection data) as serial data to the drive circuit inside the recording head 22. At this time, the head drive control unit 61 generates a transfer clock and a latch signal required for transferring image data and confirming the transfer, as well as a drive waveform used when ejecting ink droplets from the recording head 22, and outputs them to the drive circuit inside the recording head 22. The drive circuit inside the recording head 22 selectively inputs a drive waveform corresponding to the input image data to the piezoelectric element (actuator) of each nozzle of the recording head 22. The post heater 33, the infrared heater 30, the hot air fan 34, and the control unit 50 constitute the "drying unit" of the present invention.

The main scanning motor drive unit 62, under the control of the CPU 51, controls the drive of the main scanning motor 75 to control the movement of the carriage 21 in the main scanning direction. The main scanning motor 75 is a motor that moves the carriage 21 in the main scanning direction via a timing belt by rotating.

The transport motor drive unit 63 drives the media transport motor 76 under the control of the CPU 51. The media transport motor 76 is a motor that rotates the feed roller 14a shown in FIG. 1 to transport the media 17 in the sub-scanning direction.

The heater control unit 64 controls the heating of the infrared heater 30, the print heater 31, the preheater 32, and the postheater 33. The heater control unit 64 monitors the heating status of the infrared heater 30, the print heater 31, the preheater 32, and the postheater 33 using data on the temperature (media temperature) of the media 17 detected by the preheater temperature sensor 72, the print heater temperature sensor 71, the postheater temperature sensor 73, the infrared heater temperature sensor 70, and the media surface temperature sensor 74.

The heater control unit 64 also controls the infrared heater 30, print heater 31, pre-heater 32, and post-heater 33 based on temperature data acquired from the various temperature sensors 70-74. Here, the various temperature sensors 70-74 detect the temperature of the media 17 (media temperature) as described above. "Detecting the media temperature" is not limited to detecting the temperature of the media 17 itself, but also includes detecting the temperature in the vicinity of the media 17. The heater control unit 64 also controls the heaters provided in the head tank and ink path in a similar manner.

The hot air fan control unit 65 controls the hot air fan 34 to blow air at a specified temperature and volume.

The operation panel 160 is a device with input and display functions that accepts various inputs according to user operations and displays various information (e.g., information according to the accepted operations, information showing the operating status of the inkjet recording device 10, a setting screen, etc.). The operation panel 160 is, for example, configured with a liquid crystal display device (LCD: Liquid Crystal Display) equipped with a touch panel function. Note that the operation panel 160 is not limited to a liquid crystal display device, and may be, for example, configured with an organic EL (Electro-Luminescence) display device equipped with a touch panel function. Furthermore, the operation panel 160 may be provided with an operation unit such as hardware keys or a display unit such as a lamp in addition to or instead of the touch panel function.

Note that the hardware configuration of the inkjet recording device 10 shown in FIG. 2 is an example, and does not need to include all of the components shown in FIG. 2, or may include other components.

(CPU Functional Block Configuration)
3 is a diagram showing an example of a functional block configuration of a CPU according to this embodiment. The main configuration of the inkjet recording apparatus 10 according to this embodiment will be described with reference to this FIG.

As shown in FIG. 3, the functional block configuration of the CPU 51 includes a print data receiving unit 101, a print mode discrimination unit 102, a first heating control unit 103, a second heating control unit 104, and a heating control selection unit 105.

The print data receiving unit 101 receives print data from the host 150 via the host I/F 56, via a cable or network.

The print mode determination unit 102 determines the print mode by reading and analyzing the received print data.

During the heating period (preheating) in which the post heater 33 and the infrared heater 30 heat the interior of the drying unit 18 until a preset temperature is reached, the first heating control unit 103 performs heating control using a control pattern (see FIG. 4) in which the hot air fan 34 is stopped during the heating period, printing is started after the heating period ends, and blowing air using the hot air fan 34 is started.

For example, FIG. 4 is a diagram showing an example of the operation timing of the drying unit by the first heating control unit according to this embodiment. The upper part of FIG. 4 shows the operating state of the inkjet recording device 10, with the vertical axis of FIG. 4 showing each controlled object and the horizontal axis showing time. Specifically, it shows the period during which the post heater 33 and the infrared heater 30 are heated (ON: heating, OFF: non-heating), the timing of blowing air from the hot air fan 34 (ON: blowing air, OFF: stopped), and the timing of driving the feed roller 14a (ON: driving, OFF: stopped).

First, when the power is turned on, the hot air fan 34 is automatically turned ON, and the post heater 33, infrared heater 30, and feed roller 14a are all turned OFF. When the inkjet recording device 10 is in a "standby" operating state, the post heater 33 is turned ON by user operation. The post heater 33 can be turned OFF/ON by user operation.

Next, when print data is received, the infrared heater 30 is turned ON and the hot air fan 34 is turned OFF. This heating period in the operating state of the inkjet recording device 10 is called the preheating state, and heating is performed until the temperature of the infrared heater temperature sensor 70 in the drying unit 18 reaches a preset temperature. Because heating is performed by the infrared heater 30 with the hot air fan 34 stopped, the desired temperature can be raised more quickly than when blowing air with the hot air fan 34.

When the temperature of the infrared heater temperature sensor 70 reaches a preset temperature, the hot air fan 34 turns ON and the feed roller 14a starts intermittent operation, and together with the carriage 21, the recording head 22 starts main scanning to start printing. When printing is completed by operating the carriage 21, the media 17 moves to a drying state where it is transported intermittently through the drying unit 18. When the drying state ends, printing ends, and the infrared heater 30 and feed roller 14a stop and go into a standby state.

The second heating control unit 104 performs heating control using a control pattern (see FIG. 5) that starts printing without a heating period (preheating) like the first heating control unit 103. For example, FIG. 5 is a diagram showing an example of the operation timing of the drying unit by the second heating control unit according to the embodiment. The upper part of FIG. 5 shows the operating state of the inkjet recording device 10, and the vertical axis of FIG. 5 shows each controlled object, and the horizontal axis shows time. Specifically, it shows the period during which the post heater 33 and the infrared heater 30 are heated (ON: heating, OFF: non-heating), the timing of blowing air from the hot air fan 34 (ON: blowing air, OFF: stopped), and the timing of driving the feed roller 14a (ON: driving, OFF: stopped).

First, when the power is turned on, the hot air fan 34 is automatically turned ON, and the post heater 33, infrared heater 30, and feed roller 14a are all turned OFF. When the inkjet recording device 10 is in a "standby" operating state, the post heater 33 is turned ON by user operation. Up to this point, it is the same as the control pattern in Figure 4. However, the control pattern in Figure 5 differs from the control pattern in Figure 4 in that when print data is received, printing begins without a heating period (preheating), and printing ends after drying is completed.

The heating control selection unit 105 selects either the heating control pattern of the first heating control unit 103 or the second heating control unit 104 based on the printing mode determined by the printing mode determination unit 102.

(Operation of the inkjet recording device)
An outline of the operation of the inkjet recording device 10 configured as above will be described. The control unit 50 receives print data and the like from the host 150 side via a cable or a network through the host I/F 56. The CPU 51 then reads and analyzes the print data in the receive buffer included in the host I/F 56. Next, the ASIC 54 performs necessary image processing, data sorting processing, and the like, and transfers this processed data (image data) to the recording head 22 through the head drive control unit 61.

The dot pattern data for outputting an image may be generated, for example, by storing font data in ROM 52, or the image data may be expanded into bitmap data by a printer driver on the host 150 side and transferred to the inkjet recording device 10 side.

Figure 6 is a flow chart showing an example of a media drying process of an inkjet recording device according to an embodiment. When the inkjet recording device 10 receives print data (step S11), it performs a heating control determination process (step S12), and performs a printing process (step S13) and a drying process (step S14) via the selected heating control, after which the printing process ends.

The inkjet recording device 10 according to this embodiment is characterized in that in the heating control determination process of step S12, the heating control pattern of the media drying process is changed depending on the printing mode based on the printing data. In this embodiment, as shown in FIG. 7, the heating control pattern may be changed depending on whether the printing mode is faster than a preset media transport speed or is below a preset value. Also, in this embodiment, as shown in FIG. 8, the heating control pattern may be changed depending on whether the heating temperature of the printing mode is higher than a preset temperature or is below a preset value.

<When changing the heating control pattern depending on the media transport speed of the print mode>
7 is a flowchart of a subroutine showing an example of a heating control determination process based on the transport speed. In the heating control determination process of step S12, if the media transport speed of the print mode obtained by analyzing the received print data is higher than a preset transport speed (Yes in step S1211), the heating control selection unit 105 selects a control pattern by the first heating control unit 103 (step S1212), and if the media transport speed is equal to or lower than the preset transport speed (No in step S1211), the heating control selection unit 105 selects a control pattern by the second heating control unit 104 (step S1213). The transport speed is expressed by the number of scans, the feed amount per scan, etc.

In this way, in a high-productivity printing mode in which the media transport speed is faster than a preset value, the first heating control unit 103 heats the infrared heater 30 through a heating period (preheating). This makes it possible to buy time to sufficiently heat the temperature inside the drying unit 18, and prevents poor fixation of the ink on the media.

In contrast, in print modes where the media transport speed is equal to or less than the set value, it is possible to sufficiently heat the temperature inside the drying unit 18 without going through a heating period (preheating). In this case, it is possible for the infrared heater 30 to sufficiently heat the temperature inside the drying unit 18 in the time it takes for the print data to be received, printing to be started, the infrared heater 30 to be turned on, the carriage 21 to start main scanning, and for the carriage 21 to reach the drying unit 18. This allows printing to be completed earlier by not going through a heating period (preheating).

<When changing the heating control pattern depending on the heating temperature of the printing mode>
8 is a flowchart of a subroutine showing an example of a heating control determination process based on heating temperature. In the heating control determination process in step S12, if the heating temperature of the print mode analyzed in the received print data is higher than a preset temperature (Yes in step S1221), the heating control selection unit 105 selects the control pattern by the first heating control unit 103 (step S1222), and if the heating temperature is equal to or lower than the preset temperature (No in step S1221), the heating control selection unit 105 selects the control pattern by the second heating control unit 104 (step S1223).

In this way, when the heating temperature in the print mode is higher than the preset value, the first heating control unit 103 heats the infrared heater 30 through a heating period (preheating). This makes it possible to buy time to sufficiently heat the temperature inside the drying unit 18, and prevents poor fixation of the ink on the media.

In contrast, when the heating temperature in the print mode is equal to or lower than the set value, it is possible to sufficiently heat the temperature inside the drying unit 18 without going through a heating period (preheating). In this case, it is possible for the infrared heater 30 to sufficiently heat the temperature inside the drying unit 18 in the time it takes for the print data to be received, printing to be started, the infrared heater 30 to be turned on, the carriage 21 to start main scanning, and for the carriage 21 to reach the drying unit 18. This allows printing to be completed earlier by not going through a heating period (preheating).

As described above, in the inkjet recording device 10 according to this embodiment, the heating control pattern of either the first heating control unit or the second heating control unit is selected based on the print mode, and the ink on the media surface is dried by the drying unit. This makes it possible to prevent poor fixation of the ink on the media even in the highly productive transport mode.

In addition, the first heating control unit 103 and the second heating control unit 104 start heating the infrared heater 30 after receiving the print data for both heating control patterns. Therefore, by receiving the print data, the print mode and media temperature settings can be compared with the conveying speed and set temperature that are set in advance. This allows the heating control selection unit 105 to determine whether to select the first heating control unit 103 or the second heating control unit 104.

In addition, when the print mode discrimination unit 102 discriminates that the print mode is faster than the preset media transport speed, the heating control selection unit 105 selects the heating control pattern by the first heating control unit 103. On the other hand, when the print mode discrimination unit 102 discriminates that the print mode is slower than the preset media transport speed, the heating control selection unit 105 selects the heating control pattern by the second heating control unit 104.

In the slow transport speed mode, when print data is received, printing begins and the infrared heater 30 is turned on, without the need for a heating period (preheating). Heating by the infrared heater 30 from the time the carriage 21 begins main scanning until it reaches the drying unit 18 buys enough time to heat up the temperature inside the drying unit 18. This allows printing to finish early in the slow transport speed print mode, without the need for a heating period (preheating).

In addition, when the print mode discrimination unit 102 discriminates that the print mode is a higher temperature than the preset temperature, the heating control selection unit 105 selects the heating control pattern by the first heating control unit 103. On the other hand, when the print mode discrimination unit 102 discriminates that the print mode is a lower temperature than the preset temperature, the heating control selection unit 105 selects the heating control pattern by the second heating control unit 104.

In print modes with low set temperatures, printing starts when print data is received and the infrared heater 30 is turned on, without the need for a heating period (preheating). Heating by the infrared heater 30 from the time the carriage 21 starts main scanning until it reaches the drying unit 18 buys enough time to heat up the temperature inside the drying unit 18. This allows printing to finish early in print modes with low set temperatures, without the need for a heating period (preheating).

In addition, in the above-described embodiment, when at least any of the functional units of the inkjet recording device 10 is realized by executing a program, the program is provided in advance in a ROM or the like.

The program executed by the inkjet recording device 10 according to the present embodiment described above may be configured to be provided by recording it in an installable or executable file format on a computer-readable recording medium such as a CD-ROM (Compact Disc Read Only Memory), a flexible disk (FD), a CD-R (Compact Disk-Recordable), or a DVD (Digital Versatile Disc).

The program executed by the inkjet recording device 10 according to the embodiment described above may be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. The program executed by the inkjet recording device 10 according to the embodiment described above may be provided or distributed via a network such as the Internet.

The program executed by the inkjet recording device 10 of the present embodiment described above has a modular configuration including at least any of the functional units described above. In terms of actual hardware, the CPU 51 reads out the program from the storage device (ROM 52 or storage 170) described above and executes it, so that each of the functional units described above is loaded onto the main storage device (for example, RAM 53) and generated.

As described above, according to this embodiment, a liquid ejection method and a liquid ejection program are provided. The liquid ejection method of this embodiment is a liquid ejection method that uses an apparatus equipped with a heater that heats the medium on which liquid has landed, and includes a print data receiving step of receiving print data, a print mode determining step of determining a print mode based on the received print data, and a heating control selection step of selecting either a first heating control unit that heats with the heater until a preset temperature is reached and starts printing after the heating period ends, or a second heating control unit that starts printing without an intervening heating period, based on the print mode determined in the print mode determining step.

The liquid ejection program of this embodiment causes a computer that controls an apparatus equipped with a heater that heats the medium on which liquid has landed to execute a print data receiving step of receiving print data, a print mode determining step of determining a print mode based on the received print data, and a heating control selection step of selecting either a first heating control unit that heats with the heater until a preset temperature is reached and starts printing after the heating period ends, or a second heating control unit that starts printing without an intervening heating period, based on the print mode determined in the print mode determining step. The following inks are used in the liquid ejection method and liquid ejection program of this embodiment.

(ink)
The liquid used in the liquid ejection device of the present invention is an inkjet ink (hereinafter, simply referred to as ink) containing 10% by mass or more of an alcohol-based solvent with a boiling point of 180° C. or more at 1 atmospheric pressure relative to the total amount of the liquid. By using this ink, it is possible to prevent the ink from drying near the nozzle and causing nozzle clogging, and good ejection stability is obtained. The ink used in this embodiment contains water, an organic solvent, a resin, a coloring material, an additive, etc.

<Water>
The water content in the ink is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoints of the drying property and ejection reliability of the ink, however, the water content is preferably from 10% by mass to 90% by mass, and more preferably from 20% by mass to 60% by mass.

<Organic Solvent>
The ink used in the present invention contains an alcohol-based solvent having a boiling point of 180° C. or higher at 1 atmospheric pressure in an amount of 10% by mass or more based on the total amount of the liquid. If the content of the solvent is less than 10% by mass, good ejection stability cannot be obtained. The content of the solvent is preferably 30% by mass or less based on the total amount of the ink.

The ink used in the present invention preferably contains a glycol ether-based solvent having a boiling point of 180°C or higher at 1 atmospheric pressure. Such a glycol ether-based solvent can be used as a substitute for the alcohol-based solvent. When such a glycol ether-based solvent is contained, it is preferable that the content of the glycol ether-based solvent is 10% by mass or more of the total amount of the liquid. It is also preferable that the content of the glycol ether-based solvent is 30% by mass or less of the total amount of the ink.

The organic solvent to be used in combination is not particularly limited, and examples thereof include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.

Specific examples of organic solvents include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 2,4-pentanediol, and 1,5-pentanediol. polyhydric alcohols such as 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,6-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, and petriol; ethylene glycol monoethyl ether; ethylene glycol mono Examples of the alkyl ethers include polyhydric alcohols such as butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether; polyhydric alcohols such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; nitrogen-containing heterocyclic compounds such as 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, and γ-butyrolactone; amides such as formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide; amines such as monoethanolamine, diethanolamine, and triethylamine; sulfur-containing compounds such as dimethyl sulfoxide, sulfolane, and thiodiethanol; propylene carbonate; and ethylene carbonate.

The ink used in this embodiment preferably contains a compound represented by the following general formula (1). In this case, the drying and fixing properties can be improved. An example of the compound represented by the following general formula (1) is 3-methoxy-N,N-dimethylpropionamide.

In the general formula (1), R ₁ , R ₂ and R ₃ each independently represent a hydrocarbon group having 1 to 8 carbon atoms.

The organic solvent can be changed as appropriate, but it is preferable to use a solvent selected from alcohols and glycol ethers that have a boiling point of 240°C or less at 1 atmosphere. When such a solvent is used, it not only functions as a wetting agent and a compatibilizer, but also provides good drying properties.

When the ink used in this embodiment further contains a solvent selected from alcohol-based solvents and glycol ether-based solvents having a boiling point of 230° C. or higher at 1 atmosphere, it is preferable that the amount of the solvent is 10% by mass or less based on the total amount of the liquid. When this requirement is satisfied, the drying property and fixation property can be improved.

Polyol compounds having 8 or more carbon atoms and glycol ether compounds are also suitably used. Specific examples of polyol compounds having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
Specific examples of the glycol ether compound include polyhydric alcohol alkyl ethers such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether; and polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

Polyol compounds with 8 or more carbon atoms and glycol ether compounds can improve the permeability of ink when paper is used as the recording medium.

The content of the organic solvent in the ink is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of the drying property and ejection reliability of the ink, it is preferably 10% by mass or more and 60% by mass or less, and more preferably 20% by mass or more and 60% by mass or less.

<Coloring material>
The coloring material is not particularly limited, and pigments and dyes can be used.
As the pigment, inorganic pigments or organic pigments can be used. These pigments can be used alone or in combination of two or more. Mixed crystals can also be used.

Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy pigments such as gold and silver pigments, and metallic pigments.

Inorganic pigments that can be used include titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, as well as carbon black produced by known methods such as the contact method, furnace method, and thermal method.

As organic pigments, azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.), dye chelates (e.g., basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, etc. can be used. Of these pigments, those with good affinity with the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.

Specific examples of pigments for black colors include carbon blacks (C.I. Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, metals such as copper, iron (C.I. Pigment Black 11), and titanium oxide, and organic pigments such as aniline black (C.I. Pigment Black 1).

In addition, for color, C.I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104, 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C.I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C.I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48:2, 48:2 (Permanent Red 2B (Ca)), 48:3, 48:4, 49:1, 52:2, 53:1, 57:1 (Brilliant Carmine 6B), 60:1, 63:1, 63:2, 64:1, 81, 83, 88, 101 (Red ochre), 1 04, 105, 106, 108 (Cadmium Red), 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. Pigment Violet 1 (Rhodamine Lake), 3, 5:1, 16, 19, 23, 38, C.I. Pigment Blue 1, 2, 15 (Phthalocyanine Blue), 15:1, 15:2, 15:3, 15:4 (Phthalocyanine Blue), 16, 17:1, 56, 60, 63, C.I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc.

The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used. One type of dye may be used alone, or two or more types may be used in combination.
Examples of the dyes include C.I. Acid Yellow 17,23,42,44,79,142, C.I. Acid Red 52,80,82,249,254,289, C.I. Acid Blue 9,45,249, C.I. Acid Black 1,2,24,94, C.I. Food Black 1,2, C.I. Direct Yellow 1,12,24,33,50,55,58,86,132,142,144,173, C.I. Direct Red 1,4,9,80,81,225,227, C.I. Direct Blue 1,2,15,71,86,87,98,165,199,202, C.I. Directed Black 19, 38, 51, 71, 154, 168, 171, 195, C.I. Reactive Red 14, 32, 55, 79, 249, C.I. Reactive Black 3, 4, 35.

The content of colorant in the ink is preferably 0.1% by mass or more and 15% by mass or less, and more preferably 1% by mass or more and 10% by mass or less, from the viewpoints of improving image density, good fixing property and ejection stability.

Methods for dispersing a pigment to obtain an ink include a method of introducing a hydrophilic functional group into the pigment to make it a self-dispersing pigment, a method of dispersing the pigment by coating the surface of the pigment with a resin, and a method of dispersing the pigment using a dispersant.
As a method for making a pigment self-dispersible by introducing a hydrophilic functional group into the pigment, for example, a method for making the pigment dispersible in water by adding a functional group such as a sulfone group or a carboxyl group to the pigment (e.g., carbon) can be mentioned.

One method for dispersing a pigment by coating its surface with a resin is to encapsulate the pigment in a microcapsule to make it dispersible in water. This can be called a resin-coated pigment. In this case, it is not necessary for all of the pigments blended into the ink to be coated with resin, and uncoated or partially coated pigments may be dispersed in the ink as long as the effects of the present invention are not impaired.

Examples of the method for dispersing using a dispersant include a method for dispersing using a known low molecular weight dispersant or a polymeric dispersant, typified by a surfactant.
As the dispersant, for example, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, etc. can be used depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Oil Co., Ltd. and sodium naphthalenesulfonate formalin condensate can also be suitably used as dispersants.
The dispersants may be used alone or in combination of two or more.

<Pigment Dispersion>
It is possible to obtain ink by mixing a pigment with materials such as water or an organic solvent, or it is also possible to manufacture ink by mixing a pigment with other materials such as water and a dispersant to prepare a pigment dispersion, and then mixing the resulting mixture with materials such as water or an organic solvent.
The pigment dispersion is obtained by mixing and dispersing water, a pigment, a pigment dispersant, and other components as required, and adjusting the particle size. Dispersion is preferably performed using a dispersing machine.
The particle size of the pigment in the pigment dispersion is not particularly limited, but in terms of improving the dispersion stability of the pigment and improving the image quality such as ejection stability and image density, the maximum frequency in terms of the maximum number is preferably 20 nm or more and 500 nm or less, and more preferably 20 nm or more and 150 nm or less. The particle size of the pigment can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

The content of the pigment in the pigment dispersion is not particularly limited and may be appropriately selected depending on the purpose. From the viewpoints of obtaining good ejection stability and increasing image density, the content of the pigment is preferably from 0.1% by mass to 50% by mass, and more preferably from 0.1% by mass to 30% by mass.
It is preferable that the pigment dispersion is degassed, if necessary, by filtering coarse particles using a filter, a centrifugal separator, or the like.

<Resin>
The type of resin contained in the ink is not particularly limited and can be appropriately selected depending on the purpose. Examples of the resin include urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene-butadiene resin, vinyl chloride resin, acrylic styrene resin, and acrylic silicone resin.

It is preferable to use a polyurethane resin as the resin, and it is preferable that the polyurethane resin is contained in an amount of 5% by mass or more, calculated as non-volatile matter, relative to the total amount of the liquid. In this case, it is possible to improve abrasion resistance.

Resin particles made of these resins may be used. The resin particles may be dispersed in water as a dispersion medium to form a resin emulsion, and the resin particles may be mixed with materials such as coloring materials and organic solvents to obtain an ink. The resin particles may be appropriately synthesized or may be commercially available. These may be used alone or in combination of two or more types of resin particles.

The volume average particle size of the resin particles is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoint of obtaining good fixing property and high image hardness, the volume average particle size is preferably 10 nm or more and 1,000 nm or less, more preferably 10 nm or more and 200 nm or less, and particularly preferably 10 nm or more and 100 nm or less.
The volume average particle size can be measured, for example, by using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

There are no particular limitations on the resin content, and it can be selected appropriately depending on the purpose, but from the standpoint of fixation and ink storage stability, it is preferably 1% by mass or more and 30% by mass or less, and more preferably 5% by mass or more and 20% by mass or less, based on the total amount of ink.

There are no particular restrictions on the particle size of the solids in the ink, and they can be selected appropriately depending on the purpose, but in terms of improving image quality such as ejection stability and image density, the maximum frequency in terms of maximum number is preferably 20 nm or more and 1000 nm or less, and more preferably 20 nm or more and 150 nm or less. The solids include resin particles, pigment particles, etc. The particle size can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

<Additives>
If necessary, surfactants, antifoaming agents, antiseptic and antifungal agents, rust inhibitors, pH adjusters, and the like may be added to the ink.

<Surfactant>
As the surfactant, any of silicone-based surfactants, fluorine-based surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants can be used.

There are no particular limitations on the silicone surfactants, and they can be selected appropriately depending on the purpose. Among them, those that do not decompose even at high pH are preferred, such as side-chain modified polydimethylsiloxane, both-end modified polydimethylsiloxane, one-end modified polydimethylsiloxane, and both-end modified polydimethylsiloxane of the side chain, and those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group are particularly preferred because they exhibit good properties as aqueous surfactants. In addition, polyether-modified silicone surfactants can also be used as the silicone surfactant, such as a compound in which a polyalkylene oxide structure is introduced into the Si part side chain of dimethylsiloxane.

As the fluorine-based surfactant, for example, perfluoroalkyl sulfonic acid compound, perfluoroalkyl carboxylic acid compound, perfluoroalkyl phosphate compound, perfluoroalkyl ethylene oxide adduct, and polyoxyalkylene ether polymer compound having perfluoroalkyl ether group in the side chain are particularly preferred because they have low foaming properties. As the perfluoroalkyl sulfonic acid compound, for example, perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate, etc. are included. As the perfluoroalkyl carboxylic acid compound, for example, perfluoroalkyl carboxylic acid, perfluoroalkyl carboxylate, etc. are included. As the polyoxyalkylene ether polymer compound having perfluoroalkyl ether group in the side chain, for example, sulfate ester salt of polyoxyalkylene ether polymer having perfluoroalkyl ether group in the side chain, salt of polyoxyalkylene ether polymer having perfluoroalkyl ether group in the side chain, etc. are included. Examples of counter ions of the salts in these fluorosurfactants include Li, Na, _K , _{NH4 , NH3CH2CH2OH} , _NH2 ( _CH2CH2OH ) ₂ , _and NH( _{CH2CH2OH ) 3} .

Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.

Examples of nonionic surfactants include polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylamines, polyoxyethylene alkylamides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and ethylene oxide adducts of acetylene alcohol.

Examples of the anionic surfactant include polyoxyethylene alkyl ether acetates, dodecylbenzene sulfonates, laurates, and salts of polyoxyethylene alkyl ether sulfates.
These may be used alone or in combination of two or more.

The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. Examples include side-chain modified polydimethylsiloxane, both-end modified polydimethylsiloxane, one-end modified polydimethylsiloxane, and both-end modified polydimethylsiloxane of the side chain. Polyether-modified silicone surfactants having polyoxyethylene groups or polyoxyethylene polyoxypropylene groups as modifying groups are particularly preferred because they exhibit good properties as aqueous surfactants.

As such surfactants, appropriately synthesized ones or commercially available products may be used. Commercially available products are available from, for example, BYK-Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nippon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., etc.

The polyether-modified silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. For example, it can be one in which a polyalkylene oxide structure is introduced into the Si side chain of dimethylpolysiloxane, as represented by the general formula (S-1).

(In the general formula (S-1), m, n, a, and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)

As the polyether-modified silicone surfactant, commercially available products can be used, such as KF-618, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS-1906EX (Nihon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Dow Corning Toray Silicone Co., Ltd.), BYK-33, BYK-387 (BYK-Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.), etc.

The fluorosurfactant is preferably a compound having 2 to 16 fluorine-substituted carbon atoms, and more preferably a compound having 4 to 16 fluorine-substituted carbon atoms.

Fluorine-based surfactants include perfluoroalkyl phosphate compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups on the side chains. Among these, polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups on the side chains are preferred because they have low foaming properties, and fluorine-based surfactants represented by general formulas (F-1) and (F-2) are particularly preferred.

In the compound represented by the above general formula (F-1), m is preferably an integer from 0 to 10 in order to impart water solubility, and n is preferably an integer from 0 to 40.

C _n F _2n+1 -CH ₂ CH(OH)CH ₂ -O-(CH ₂ CH ₂ O) _a -Y General formula (F-2)

In the compound represented by the above general formula (F-2), Y is H, or CnF _2n+1 where n is an integer from 1 to 6, or CH ₂ CH(OH)CH ₂ -C _n F _2n+1 where n is an integer from 4 to 6, or C _p H _2p+1 where p is an integer from 1 to 19. a is an integer from 4 to 14.

As the fluorosurfactant, commercially available products may be used. Examples of such commercially available products include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Fullard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, and FC-431 (all manufactured by Sumitomo 3M Limited); Megafa F-470, F-1405, F-474 (all manufactured by Dainippon Ink & Chemicals, Inc.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by Chemours); FT-110, FT- 250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omnova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.), and the like. Among these, preferred are those which have good print quality, particularly color development and paper adhesion. Particularly preferred are FS-3100, FS-34, and FS-300 manufactured by Chemours, FT-110, FT-250, FT-251, FT-400S, FT-150, and FT-400SW manufactured by Neos Co., Ltd., Polyfox PF-151N manufactured by Omnova, and Unidyne DSN-403N manufactured by Daikin Industries, Ltd., due to their significantly improved permeability, wettability, and dye uniformity.

The content of the surfactant in the ink is not particularly limited and can be selected appropriately depending on the purpose, but from the viewpoint of excellent wettability, ejection stability, and improved image quality, it is preferably 0.001% by mass or more and 5% by mass or less, and more preferably 0.05% by mass or more and 5% by mass or less.

<Antifoaming agent>
The defoaming agent is not particularly limited, and examples thereof include silicone-based defoaming agents, polyether-based defoaming agents, and fatty acid ester-based defoaming agents. These may be used alone or in combination of two or more. Among these, silicone-based defoaming agents are preferred because of their excellent foam breaking effect.

<Anti-septic and anti-fungal agents>
The antiseptic and antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one.

<pH Adjuster>
There are no particular limitations on the pH adjuster, so long as it is capable of adjusting the pH to 7 or higher, and examples of the pH adjuster include amines such as diethanolamine and triethanolamine.

<Ink properties>
The physical properties of the ink are not particularly limited and can be appropriately selected depending on the purpose. For example, it is preferable that the viscosity, surface tension, pH, etc. are within the following ranges.
The viscosity of the ink at 25°C is preferably 5 mPa·s or more and 30 mPa·s or less, and more preferably 5 mPa·s or more and 25 mPa·s or less, in terms of improving the print density and character quality and obtaining good ejection properties. Here, the viscosity can be measured using, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.). The measurement conditions are 25°C, a standard cone rotor (1°34'×R24), a sample liquid volume of 1.2 mL, a rotation speed of 50 rpm, and 3 minutes.
The surface tension of the ink is preferably 35 mN/m or less, and more preferably 32 mN/m or less at 25° C., in order to ensure that the ink is appropriately leveled on the recording medium and the drying time of the ink is shortened.
The pH of the ink is preferably from 7 to 12, and more preferably from 8 to 11, from the viewpoint of preventing corrosion of metal members that come into contact with the ink.

<Recording media>
There are no particular limitations on the recording medium, and although plain paper, glossy paper, special paper, cloth, etc. can be used, good image formation is also possible using a non-permeable substrate.
The non-permeable substrate is a substrate having a surface with low water permeability and absorbency, and includes materials that have many cavities inside but are not open to the outside. More quantitatively, the non-permeable substrate is a substrate having a water absorption amount of 10 mL/m2 ^{or less} from the start of contact to 30 msec ^1/2 in the Bristow method.
As the non-permeable substrate, for example, a plastic film such as a polyvinyl chloride resin film, a polyethylene terephthalate (PET) film, a polypropylene film, a polyethylene film, or a polycarbonate film can be suitably used.

The polypropylene and polyethylene are not particularly limited, and examples thereof include AR1025, AR1056, AR1082, EC1082, 1082D, 1073D, 1056D, 1025D, and FR1073 (Asahi DuPont Flashspan). Products Co., Ltd.), P2002, P2102, P2108, P2161, P2171, P2111, P4266, P5767, P3162, P6181, P8121, P1162, P1111, P1128, P1181, P1153, P1157, P1146, P1147, P1171 (Toyobo Co., Ltd.), YPI, Aqua Yupo, Super Yupo, Ultra Yupo, New Yupo, Yupo Illumination Paper, Yupo Building Materials Paper, Yupo High Gloss, Yupo Jet, Metallic Yupo (Yupo Corporation), etc.

<Recordings>
The ink recorded matter obtained by the present invention has an image formed on a recording medium using the ink described above.
A recorded matter can be obtained by recording using an inkjet recording apparatus and an inkjet recording method.

<Recording device and recording method>
The configuration of the liquid ejection device of the present invention is as described above, but a supplementary explanation will be given below.
The ink used in the present invention can be suitably used in various recording devices using the ink jet recording method, such as printers, facsimile machines, copying machines, printer/fax/copier combination machines, and three-dimensional modeling devices.
In this application, the recording apparatus and recording method refer to an apparatus capable of ejecting ink or various treatment liquids onto a recording medium, and a method of recording using the apparatus. The recording medium refers to an object onto which ink or various treatment liquids can be attached even temporarily.
This recording device can include not only a head portion that ejects ink, but also means related to feeding, transporting, and discharging the recording medium, as well as other devices called pre-processing devices and post-processing devices.

The recording device and recording method may have a heating means used in the heating step and a drying means used in the drying step. The heating means and drying means include, for example, means for heating and drying the printed surface and back surface of the recording medium. The heating means and drying means are not particularly limited, but for example, a hot air heater or an infrared heater can be used. Heating and drying can be performed before, during, or after printing.

When an infrared heater is used, it is preferable that the heater is equipped with at least a near-infrared irradiation device.
Known near-infrared irradiation devices are devices that consist of a halogen lamp and a reflecting mirror. Products that attempt to realize efficient heating by incorporating a halogen heater into the reflecting mirror to form a heating unit have been commercialized, such as UH-USC-CL300, UHUSC-CL700, UH-USC-CL1000, UH-USD-CL300, UHUSD-CL700, UH-USD-CL1000, UH-MA1-CL300, UHMA1-CL700, and UH-MA1-CL1000 (all manufactured by Ushio Electric Co., Ltd.).

Furthermore, the recording device and recording method are not limited to those that visualize meaningful images such as characters and figures with ink. For example, those that form patterns such as geometric designs and those that form three-dimensional images are also included.
Furthermore, unless otherwise specified, the recording apparatus includes both a serial type apparatus in which the ejection head moves and a line type apparatus in which the ejection head does not move.

Furthermore, this recording device includes not only desktop types, but also wide recording devices that can print on A0-sized recording media, and continuous feed printers that can use continuous paper wound into a roll as the recording medium.

Furthermore, another example of a recording device will be described with reference to Figs. 9 and 10. Fig. 9 is a perspective view of the device. Fig. 10 is a perspective view of the main tank. An image forming device 400 as an example of a recording device is a serial type image forming device. The heater, fan, etc. have the same configuration as described above.

A mechanism section 420 is provided within the exterior 401 of the image forming device 400. Each ink storage section 411 of the main tanks 410 (410k, 410c, 410m, 410y) for each color, black (K), cyan (C), magenta (M), and yellow (Y), is formed from a packaging material such as an aluminum laminate film. The ink storage section 411 is housed within a storage container case 414 made of, for example, plastic. In this way, the main tanks 410 are used as ink cartridges for each color.

On the other hand, a cartridge holder 404 is provided at the rear of the opening when the cover 401c of the device body is opened. A main tank 410 is removably attached to the cartridge holder 404. This allows each ink outlet 413 of the main tank 410 to communicate with the ejection head 434 for each color via the supply tube 436 for each color, making it possible to eject ink from the ejection head 434 onto a recording medium.

This recording apparatus can include not only a portion that ejects ink, but also devices called pre-processing devices and post-processing devices.
As an embodiment of the pre-treatment device and the post-treatment device, a liquid storage section having a pre-treatment liquid and a liquid ejection head, similar to the case of inks such as black (K), cyan (C), magenta (M), and yellow (Y), are added, and the pre-treatment liquid and the post-treatment liquid are ejected by an inkjet recording method.
As another embodiment of the pre-treatment device and the post-treatment device, there is an embodiment in which a pre-treatment device and a post-treatment device using a method other than the inkjet recording method, for example, a blade coating method, a roll coating method, or a spray coating method, are provided.

The ink can be used in a wide variety of ways, not just inkjet recording. In addition to inkjet recording, other methods include blade coating, gravure coating, bar coating, roll coating, dip coating, curtain coating, slide coating, die coating, and spray coating.

In the present invention, in order to improve drying properties and fixation to non-permeable substrates, the drying temperature during recording is preferably 50°C or higher. There is no particular upper limit to the drying temperature during recording, and it can be selected appropriately depending on the purpose, but from the standpoint of safety and thermal deformation of the substrate, it is preferable that it be 200°C or lower. There is no particular limit to the drying temperature before and after recording, and it can be selected appropriately depending on the purpose.

In addition, in the terminology of this invention, image formation, recording, printing, printing, etc. are all synonymous.

The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" means "parts by mass" and "%" means "% by mass" except in the evaluation criteria.

(Examples 1 to 7, Comparative Examples 1 and 2)
<Preparation of Black Pigment Dispersion>
The following mixture was premixed and then circulated and dispersed for 7 hours in a disk-type bead mill (KDL type, manufactured by Shinmaru Enterprises Co., Ltd., media: zirconia balls with a diameter of 0.3 mm) to obtain a self-dispersed black pigment dispersion (pigment solids concentration: 15% by mass).

- Pigment dispersion formulation -
Carbon black pigment (product name: Monarch 800, manufactured by Cabot Corporation) 15 parts by mass Anionic surfactant (product name: Paionin A-51-B, manufactured by Takemoto Oil Co., Ltd.) 2 parts by mass Ion-exchanged water 83 parts by mass

<Preparation of Ink 1>
The following formulation was mixed with ion-exchanged water to make a total of 100 parts, and after preparation, the mixture was mixed and stirred, and filtered through a 5 μm filter (Minisart, manufactured by Sartorius) to obtain [Ink 1] of Example 1.

- Ink formulation -
Pigment dispersion 20 parts Superflex 300 (polyurethane resin manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content concentration: 30% by mass) 16.7 parts KF-353 (siloxane-based surfactant, manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 parts 2,3-butanediol (boiling point 180°C) 10.0 parts 3-methoxy-N,N-dimethylpropionamide (boiling point 216°C) 10.0 parts Proxel LV (preservative manufactured by Avecia) 0.1 parts Ion-exchanged water balance

<Ink Compositions 2 to 9>
Inks of Examples 2 to 7 and Comparative Examples 1 and 2 were prepared in the same manner as [Ink 1] using the formulations shown in Table 1. However, the following materials were used in the tables other than those listed above.

J-450 (styrene acrylic resin particles, non-volatile content 42%, manufactured by Johnson Polymer)
・1,3-butanediol (boiling point 207°C)
・2-ethyl-1,6-hexanediol (boiling point 243°C)
3-Methoxy-3-methylbutanol (boiling point 174°C)

(evaluation)
The ink thus obtained was evaluated for drying property, fixing property (beading), abrasion resistance, and ejection stability as described below. The results are shown in Table 1.

<Formation of solid image>
An inkjet printer IPSiO GX5000 (manufactured by Ricoh Company, Ltd.) was filled with each of the inks of Examples 1 to 9 and Comparative Examples 1 and 2. The inkjet printer used here had a similar configuration to the device shown in Fig. 1. Using this inkjet printer, printing was performed at a resolution of 600 dpi on a polyvinyl chloride film (CPPVWP1300, manufactured by Sakurai Co., Ltd., hereinafter also referred to as "PVC film").
Immediately after printing, the PVC film was passed through the drying unit shown in Figure 1 at a speed of 2 m/min. In the drying unit, hot air at 70°C was blown by a hot air fan so that the blown air hit the post heater and the infrared heater.
In this example, a print mode is determined to be one in which the media transport speed is faster than a preset speed, and a heating control pattern is selected by the first heating control unit to form an image.

<Drying property>
A filter paper was pressed against the solid image formed on the PVC film, and the condition of transfer onto the filter paper was visually observed and evaluated according to the following criteria: A rating of B or higher is desirable for practical use.

[Evaluation Criteria]
A: Almost no pigment transfer to the filter paper is observed.
B: Some pigment transfer is observed.
C: Pigment clearly transferred.

<Fixation (beading)>
The solid image formed on the PVC film was visually observed for uneven recording, and the fixing property (beading) was evaluated based on the following evaluation criteria: A rating of B or higher is desirable for practical use.

[Evaluation Criteria]
A: Very good (no beading at all)
B: Good (slight beading observed)
C: Normal (with beading)
D: Poor (significant beading)

<Abrasion resistance>
A solid image formed on a PVC film was rubbed with a cotton cloth 10 times, and the degree of pigment transfer onto the cotton cloth was visually observed and evaluated according to the following criteria: A rating of B or higher is desirable for practical use.

[Evaluation Criteria]
A: Almost no pigment transfer to the cotton cloth is observed.
B: Some pigment transfer is observed.
C: Pigment clearly transferred.

<Discharge stability>
The ejection stability was evaluated by performing solid printing with a printing width of 1 m using an inkjet printer (device name: RICOH Pro L4160 manufactured by Ricoh Co., Ltd.). The inkjet printer used here has the same configuration as the device shown in FIG.
The ejection stability was evaluated by printing a nozzle check pattern every 1 m of printing length and counting the number of nozzles that had dropped out over a printing length of 5 m. A rating of B or higher is desirable for practical use.

[Evaluation Criteria]
A: No discharge disturbance or non-discharge at all. B: Discharge disturbance or non-discharge occurs in 5 nozzles or less. C: Discharge disturbance or non-discharge occurs in 5 nozzles or more and up to 50 nozzles or less. D: Discharge disturbance or non-discharge occurs in more than 50 nozzles.

It can be seen that Examples 1 to 3 are preferred embodiments of the present invention, and have excellent drying properties and ejection stability, and can provide images with high abrasion resistance and fixability even when printed on a non-permeable recording medium.
Example 4 is an example in which the amount of polyurethane resin added is slightly small, and as a result, the fixing property and the abrasion resistance were inferior to those of Examples 1-3.
Example 5 is an example in which no polyurethane resin was used, and the result was inferior to Examples 1-3 in abrasion resistance.
Example 6 is an example that does not contain the compound of general formula (1), and the drying property and fixation property were inferior to those of Examples 1-3.
Example 7 is an example in which the amount of alcohol having a boiling point of 230° C. or more added is slightly large, and the drying property and fixation property were inferior to those of Examples 1-3.

Comparative Example 1 is an example in which a glycol ether having a boiling point of less than 180° C. was used, and the ejection stability was inferior to that of the Examples.
Comparative Example 2 is an example in which the content of alcohol having a boiling point of 180° C. or higher is less than 10%, and the ejection stability was inferior to that of the Examples.

REFERENCE SIGNS LIST 10 Inkjet recording device 12 Roll media storage section 13 Winding roll 14 Conveying section 14a Feed roller 14b Pressing roller 15 Paper feed guide plate 16 Paper discharge guide plate 17 Media 18 Drying unit 21 Carriage 22 Recording head 23 Platen 30 Infrared heater 30a Infrared heater support member 31 Print heater 32 Pre-heater 33 Post-heater 34 Hot air fan 50 Control section 51 CPU
52 ROM
53 RAM
54 ASICs
55 I/O
56 Host I/F
61 Head drive control section 62 Main scanning motor drive section 63 Conveying motor drive section 64 Heater control section 65 Hot air fan control section 70 Infrared heater temperature sensor 71 Print heater temperature sensor 72 Pre-heater temperature sensor 73 Post-heater temperature sensor 74 Media surface temperature sensor 75 Main scanning motor 76 Media conveying motor 101 Print data receiving section 102 Print mode discrimination section 103 First heating control section 104 Second heating control section 105 Heating control selection section 150 Host 160 Operation panel 170 Storage 400 Image forming apparatus 401 Exterior 401c Cover 404 Cartridge holder 410, 410k, 410c, 410m, 410y Main tank 411 Ink storage section 413 Ink outlet 414 Storage container case 420 Mechanical section 434 Ejection head 436 Supply tube L Ink storage container

Patent No. 5970689

Claims (9)

a heater for heating the medium on which the liquid has landed;
A print data receiving unit that receives print data;
a print mode determination unit that determines a print mode based on the received print data;
a first heating control unit that heats the heater until a preset temperature is reached and starts printing after a heating period ends;
A second heating control unit that starts printing without an intervening heating period;
a heating control selection unit that selects heating control of either the first heating control unit or the second heating control unit based on a printing mode determined by the printing mode determination unit,
the liquid is an ink-jet ink containing, based on the total amount of the liquid, 10% by mass or more of an alcohol-based solvent having a boiling point of 180° C. or higher under one atmospheric pressure;
The heating control selection unit is
When the print mode discrimination unit discriminates that the print mode is a print mode having a temperature higher than a preset temperature, a heating control pattern is selected by the first heating control unit,
The liquid ejection device according to claim 1, wherein when the print mode determination unit determines that the print mode is a lower temperature than a preset temperature, a heating control pattern for the second heating control unit is selected. the heater includes a post-heater that heats the back surface of the medium and an infrared heater that heats the front surface of the medium;
a drying unit is configured to dry the liquid that has landed on the medium by using a fan that blows air onto the surface of the medium and the heater;
The liquid ejection device according to claim 1, characterized in that the first heating control unit stops the fan during a heating period in which the drying unit is heated by the post heater and the infrared heater, and after the heating period ends, starts printing and starts blowing air using the fan. The liquid ejection device according to claim 2, characterized in that the first heating control unit and the second heating control unit start heating the infrared heater after receiving the print data. The liquid ejection device according to any one of claims 1 to 3, characterized in that the preset temperature is the temperature to which the heater is heated. The liquid ejection device according to any one of claims 1 to 4, characterized in that the liquid further contains a solvent selected from an alcohol-based solvent and a glycol ether-based solvent having a boiling point of 230°C or higher at 1 atmosphere, and the liquid contains the solvent in an amount of 10% by mass or less based on the total amount of the liquid. 6. The liquid ejection device according to claim 1 , wherein the liquid contains polyurethane resin in an amount of 5% by mass or more based on the total amount of the liquid. 7. The liquid ejection device according to claim 1, wherein the liquid contains a compound represented by the following general formula (1):

In the general formula (1), R ₁ , R ₂ and R ₃ each independently represent a hydrocarbon group having 1 to 8 carbon atoms. A liquid ejection method using a device equipped with a heater that heats a medium on which liquid has landed, comprising:
a print data receiving step of receiving print data;
a print mode determination step of determining a print mode based on the received print data;
a heating control selection step for selecting either a first heating control unit that heats the printing medium with a heater until a preset temperature is reached and starts printing after a heating period ends, or a second heating control unit that starts printing without an intervening heating period, based on the printing mode determined in the printing mode determination step;
Including,
the liquid is an ink-jet ink containing, based on the total amount of the liquid, 10% by mass or more of an alcohol-based solvent having a boiling point of 180° C. or higher under one atmospheric pressure;
The heating control selection step includes:
When the print mode determination step determines that the print mode is a print mode having a temperature higher than a preset temperature, a heating control pattern for the first heating control unit is selected.
a heating control pattern for the second heating control unit being selected when the print mode determining step determines that the print mode is a print mode having a temperature lower than a preset temperature; A computer that controls an apparatus including a heater that heats a medium on which a liquid is landed,
a print data receiving step of receiving print data;
a print mode determination step of determining a print mode based on the received print data;
a heating control selection step for selecting either a first heating control unit that heats the printing medium with a heater until a preset temperature is reached and starts printing after a heating period ends, or a second heating control unit that starts printing without an intervening heating period, based on the printing mode determined in the printing mode determination step;
A liquid ejection program for executing
the liquid provided in the device is an ink-jet ink containing 10% by mass or more of an alcohol-based solvent having a boiling point of 180° C. or more under one atmospheric pressure, based on the total amount of the liquid;
The heating control selection step includes:
When the print mode determination step determines that the print mode is a print mode having a temperature higher than a preset temperature, a heating control pattern for the first heating control unit is selected.
a liquid ejection program, comprising: a liquid ejection control unit that selects a heating control pattern for the second heating control unit when the print mode determining step determines that the print mode is a lower temperature than a preset temperature.

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