Liquid ejection device and method for driving liquid ejection device

Abstract

To provide a liquid ejection device and a method for driving the liquid ejection device, which are capable of executing optimal aging processing for a drive element according to user requirements.SOLUTION: A liquid ejection device comprises: a liquid ejection head including a nozzle that ejects liquid and a drive element; a correspondence information acquisition unit 242 configured to acquire correspondence information indicating correspondence between a driving decrease amount and a drive time of the drive element; an aging processing unit 241 configured to perform aging processing by driving the drive element before printing to reduce the driving amount of the drive element based on the correspondence information; and an ejection control unit 240 configured to drive the drive element after the aging processing so as to eject the liquid.SELECTED DRAWING: Figure 12

Description

Technical Field

[0001] The present invention relates to a liquid ejection device including a liquid ejection head that ejects a liquid from a nozzle, and a method for driving the liquid ejection device.

Background Art

[0002] A liquid ejection device typified by an inkjet recording device such as an inkjet printer includes a liquid ejection head capable of ejecting a liquid such as ink stored in a cartridge, a tank, or the like as droplets.

[0003] The liquid ejection head ejects droplets from a nozzle by causing a pressure change in the liquid by a driving element typified by a piezoelectric actuator. When the driving element is repeatedly driven, the displacement amount decreases. In other words, the decrease in the displacement amount of the driving element from the initial stage of driving (driving decrease amount) becomes large after driving for a certain period. This driving decrease amount changes steeply when the number of driving times is not so large from the initial stage of driving, but the change becomes gentle when the number of driving times reaches a certain level. That is, the closer to the initial stage of driving, the steeper the change in the driving decrease amount, so there is a risk that variations will occur in the ejection characteristics. Therefore, by driving the driving element in advance under predetermined conditions so that the change in the driving decrease amount becomes gentle to a certain extent and performing an aging process to stabilize the displacement amount, and then using the liquid ejection head, it is possible to suppress variations in the ejection characteristics and perform stable ejection of droplets (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, although the change in the drive reduction amount becomes gradual when the aging process of the drive element is performed, there is also a risk of other problems occurring. For example, by performing the aging process, the lifespan of the drive element is shortened. In addition to lifespan, since the aging process is a process of deliberately deteriorating the drive element, there is a possibility that the discharge amount decreases due to a decrease in the displacement amount itself by performing the aging process, or that the load on the electric circuit increases due to deterioration of the electrical characteristics. Thus, although the variation in discharge characteristics can be reduced by the aging process, which of the adverse effects of the aging process, such as shortening of the lifespan, is prioritized depends on the desires of the user who uses the liquid ejection head. In the prior art, it has been difficult to flexibly respond to such different desires of users, for example, whether to prioritize the variation in discharge characteristics or the length of the lifespan.

Means for Solving the Problems

[0006] An aspect of the present invention for solving the above problems is a liquid ejection device including a liquid ejection head including a nozzle for ejecting a liquid and a drive element, a correspondence relationship information acquisition unit that acquires correspondence relationship information indicating a correspondence relationship between a drive time and a drive reduction amount of the drive element, an aging process unit that performs an aging process for reducing a drive amount of the drive element by driving the drive element before printing based on the correspondence relationship information, and an ejection control unit that drives the drive element to eject a liquid after the aging process.

[0007] Another aspect of the present invention is a driving method of a liquid ejection device including a liquid ejection head including a nozzle for ejecting a liquid and a drive element, the method including acquiring correspondence relationship information indicating a correspondence relationship between a drive time and a drive reduction amount of the drive element, and performing an aging process for reducing a drive amount of the drive element by driving the drive element before printing based on the acquired correspondence relationship information.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] The present invention will be described in detail based on embodiments. However, the following description shows one aspect of the present invention and can be arbitrarily changed within the scope of the present invention. In each figure, the same reference numerals are used to indicate the same members, and the description is appropriately omitted. In each figure, X, Y, and Z represent three mutually orthogonal spatial axes. In this specification, the directions along these axes are referred to as the X direction, the Y direction, and the Z direction. The direction in which the arrow in each figure points is defined as the positive (+) direction, and the opposite direction of the arrow is defined as the negative (-) direction. Further, the Z direction indicates the vertical direction, the +Z direction indicates vertically downward, and the -Z direction indicates vertically upward. Furthermore, for the directions of the three spatial axes without limiting the positive and negative directions, they are described as the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0010] (Embodiment 1) FIG. 1 is an external view of a liquid ejection device 1 according to Embodiment 1 of the present invention. FIG. 2 is a diagram showing a schematic configuration of the liquid ejection device 1. As shown in the figure, the liquid ejection device 1 includes a liquid ejection head H, conveys a medium S in the X-axis direction, and reciprocates the liquid ejection head H in the Y-axis direction while ejecting liquid in the +Z direction from the liquid ejection head H toward the medium S to perform printing, that is, a so-called serial printer. As the medium S, any material such as recording paper or a resin film can be used in addition to cloth.

[0011] The liquid ejection device 1 includes a liquid ejection head H, a liquid storage unit 3, a control unit 4 which is a control unit, a conveyance mechanism 5 that feeds out the medium S, a movement mechanism 6, and a housing 2 in which these are housed.

[0012] The liquid ejection head H ejects the liquid supplied from the liquid storage unit 3 that stores the liquid as droplets in the +Z direction.

[0013] The liquid storage unit 3 stores a plurality of types of liquids with different colors and components ejected from the liquid ejection head H individually. Examples of the liquid storage unit 3 include a cartridge detachable from the liquid ejection device 1, a bag-shaped ink pack formed of a flexible film, an ink tank capable of refilling ink, etc. Note that in FIG. 2, one liquid storage unit 3 is illustrated. Incidentally, the liquid storage unit 3 may be a liquid storage unit 3 having divided rooms for storing a plurality of types of liquids individually, or may be a plurality of liquid storage units 3 provided individually according to a plurality of types of liquids. Also, the liquid storage unit 3 may be divided into a main tank and a sub-tank. A configuration may be adopted in which the sub-tank is connected to the liquid ejection head H and the liquid consumed by ejecting droplets from the liquid ejection head H is replenished from the main tank to the sub-tank.

[0014] The control unit 4 comprehensively controls each element of the liquid ejection device 1, that is, the liquid ejection head H, the conveyance mechanism 5, the moving mechanism 6, etc.

[0015] The conveyance mechanism 5 conveys the medium S in the X-axis direction and has conveyance rollers 5a. The conveyance mechanism 5 conveys the medium S in the X-axis direction by rotating the conveyance rollers 5a. The conveyance rollers 5a are rotated by driving a conveyance motor (not shown). The control unit 4 controls the conveyance of the medium S by controlling the driving of the medium conveyance motor. Note that the conveyance mechanism 5 for conveying the medium S is not limited to one including the conveyance rollers 5a, and for example, a mechanism that conveys the medium S by a belt or a drum may be used.

[0016] The moving mechanism 6 is a mechanism for reciprocating the liquid ejection head H in the Y-axis direction, and includes a holder 7 and a conveyor belt 8. The holder 7 is a so-called carriage that holds the liquid ejection head H and is fixed to the conveyor belt 8. The conveyor belt 8 is an endless belt installed along the Y-axis direction. The conveyor belt 8 rotates by the drive of a drive motor (not shown). The control unit 4 controls the drive of the conveyor motor to rotate the conveyor belt 8, and reciprocates the liquid ejection head H together with the holder 7 in the Y-axis direction. Note that the holder 7 may be configured to carry the liquid storage unit 3 together with the liquid ejection head H.

[0017] The housing 2 has an operation panel 9 fixed to the outer periphery. The operation panel 9 includes a display device 9a which is an example of a display unit, and an operation device 9b which is an example of a reception unit that receives user support. The display device 9a is composed of, for example, a liquid crystal display, an organic EL display, an LED lamp, etc., and displays various information. The operation device 9b is composed of various switches capable of receiving input by the user. Examples of the switches of the operation device 9b include, for example, a direction switch for operating the position of the cursor, a decision switch for making a decision, a cancel switch, a power switch, etc. Note that the display device may be a touch panel capable of receiving input by the user. In the case of a touch panel, the touch panel serves as both the display unit and the reception unit.

[0018] Under the control of the control unit 4, the liquid ejection head H performs an ejection operation of ejecting the liquid supplied from the liquid storage unit 3 as droplets in the +Z direction from each of the plurality of nozzles 21 (see FIG. 3). By performing the ejection operation by the liquid ejection head H in parallel with the conveyance of the medium S by the conveyance mechanism 5 and the reciprocating movement of the liquid ejection head H by the moving mechanism 6, so-called printing in which the liquid is applied to the medium S is performed.

[0019] FIG. 3 is a cross-sectional view of the liquid ejection head H. Note that, for each direction of the liquid ejection head H, the description will be based on the directions when mounted on the liquid ejection device 1, that is, the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0020] As shown in the figure, the liquid injection head H includes a flow path forming substrate 10, a communication plate 15, a nozzle plate 20 in which a plurality of nozzles 21 are formed, a protection substrate 30, a case member 40, and a piezoelectric actuator 300.

[0021] The flow path forming substrate 10 is made of, for example, a silicon substrate, a glass substrate, an SOI substrate, or various ceramic substrates. A plurality of pressure chambers 12 are arranged side by side along the X-axis direction on the flow path forming substrate 10. The plurality of pressure chambers 12 are arranged on a straight line along the X-axis direction so as to be at the same position in the Y-axis direction. In the present embodiment, two rows of pressure chamber columns in which the pressure chambers 12 are arranged side by side along the X-axis direction are provided in the Y-axis direction. Each pressure chamber 12 constituting these two rows of pressure chamber columns is arranged at the same position in the X-axis direction. Note that the two rows of pressure chamber columns may be arranged with a shift of half the pitch of the pressure chambers 12, that is, a so-called half pitch, in the X-axis direction. That is, all the pressure chambers 12 of the two rows of pressure chamber columns may be arranged in a staggered manner along the X-axis direction.

[0022] The communication plate 15 and the nozzle plate 20 are sequentially laminated on the surface of the flow path forming substrate 10 facing the +Z direction. The diaphragm 50 and the piezoelectric actuator 300 are sequentially laminated on the surface of the flow path forming substrate 10 facing the -Z direction.

[0023] The communication plate 15 is composed of a plate-shaped member joined to the surface of the flow path forming substrate 10 facing the +Z direction. The communication plate 15 is provided with a nozzle communication path 16 that communicates the pressure chamber 12 and the nozzle 21. Further, the communication plate 15 is provided with a first manifold portion 17 and a second manifold portion 18 that constitute a part of a manifold 100 that serves as a common liquid chamber in which a plurality of pressure chambers 12 communicate in common. The first manifold portion 17 is provided penetrating the communication plate 15 in the Z-axis direction. Also, the second manifold portion 18 is provided opening to the surface facing the +Z direction without penetrating the communication plate 15 in the Z-axis direction. Furthermore, supply communication paths 19 that communicate with the pressure chambers 12 are provided independently for each of the pressure chambers 12 in the communication plate 15. The supply communication path 19 communicates the second manifold portion 18 and the pressure chamber 12 to supply the ink in the manifold 100 to the pressure chamber 12. As such a communication plate 15, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, a metal substrate such as a stainless steel substrate, etc. are used.

[0024] The nozzle plate 20 is joined to the surface of the communication plate 15 opposite to the flow path forming substrate 10, that is, the surface facing the +Z direction. A plurality of nozzles 21 that communicate with each pressure chamber 12 via the nozzle communication path 16 are formed in the nozzle plate 20. In the present embodiment, a plurality of nozzles 21 are arranged in a row along the X-axis direction for each pressure chamber row. That is, in the present embodiment, nozzle rows in which the nozzles 21 are arranged side by side along the X-axis direction are provided in two rows separated in the Y-axis direction. Each nozzle 21 constituting these two rows of nozzle rows is arranged to be at the same position in the X-axis direction. Of course, when the two rows of pressure chamber rows are arranged at positions shifted by half a pitch of the pressure chamber 12 from each other in the X-axis direction, the two rows of nozzle rows may also be arranged shifted by half a pitch of the nozzle 21 from each other in the X-axis direction in the same manner. That is, all the nozzles 21 of the two rows of nozzle rows may be arranged in a staggered pattern along the X-axis direction.

[0025] As such a nozzle plate 20, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, a metal substrate such as a stainless steel substrate, an organic material such as a polyimide resin, etc. are used. The surface of the nozzle plate 20 facing the +Z direction constitutes a part of the ejection surface of the liquid ejection head H.

[0026] In this embodiment, the diaphragm 50 includes an elastic film 51 made of silicon oxide provided on the side of the flow path forming substrate 10, and an insulator film 52 made of zirconium oxide provided on the surface of the elastic film 51 facing the -Z direction. Note that the diaphragm 50 may be composed of only the elastic film 51, may be composed of only the insulator film 52, or may have a configuration including other films in addition to the elastic film 51 and the insulator film 52.

[0027] The piezoelectric actuator 300 includes a first electrode 60, a piezoelectric layer 70, and a second electrode 80 that are sequentially stacked on the diaphragm 50 in the -Z direction. Such a piezoelectric actuator 300 is also referred to as a piezoelectric element, and refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. Further, when a voltage is applied between the first electrode 60 and the second electrode 80, the portion where piezoelectric strain occurs in the piezoelectric layer 70 is referred to as an active portion 310. That is, the active portion 310 refers to the portion where the piezoelectric layer 70 is sandwiched between the first electrode 60 and the second electrode 80. In this embodiment, an active portion 310 is formed for each pressure chamber 12. These plurality of active portions 310 serve as "driving elements" that cause a pressure change in the ink in the pressure chamber 12. Generally, one of the electrodes of the active portion 310 is configured as an individual electrode independent for each active portion 310, and the other electrode is configured as a common electrode common to the plurality of active portions 310. In this embodiment, the first electrode 60 is divided for each active portion 310 to form an individual electrode of the active portion 310, and the second electrode 80 is continuously provided across the plurality of active portions 310 to form a common electrode of the plurality of active portions 310. Of course, the first electrode 60 may form a common electrode, and the second electrode 80 may form an individual electrode.

[0028] The piezoelectric layer 70 is configured using, for example, a piezoelectric material made of a complex oxide having a perovskite structure represented by the general formula ABO3.

[0029] Also, an individual lead electrode 91, which is a lead-out wiring, is drawn out from the first electrode 60. Further, a common lead electrode, which is a lead-out wiring not shown, is drawn out from the second electrode 80. A flexible wiring board 110 is connected to the ends of these individual lead electrode 91 and the common lead electrode on the side opposite to the end connected to the piezoelectric actuator 300. The wiring board 110 is mounted with a drive signal selection circuit 111 having a plurality of switching elements for selecting whether to supply a drive signal (COM) for driving each of the active parts 310 to each of the active parts 310. That is, the wiring board 110 in the present embodiment is a COF (Chip On Film). Note that the drive signal selection circuit 111 may not be provided on the wiring board 110. That is, the wiring board 110 may be an FFC (Flexible Flat Cable), an FPC (Flexible Printed Circuits), or the like.

[0030] A protection substrate 30 having substantially the same size as the flow path forming substrate 10 is joined to the surface of the flow path forming substrate 10 facing the -Z direction. The protection substrate 30 has a housing part 31 which is a space for protecting the piezoelectric actuator 300. The housing part 31 is provided independently for each column of the piezoelectric actuators 300 arranged side by side in the X-axis direction, and two are formed side by side in the Y-axis direction. Further, the protection substrate 30 is provided with a through hole 32 penetrating in the Z-axis direction between the two housing parts 31 arranged side by side in the Y-axis direction. The ends of the individual lead electrode 91 and the common lead electrode not shown, which are drawn out from the electrodes of the piezoelectric actuator 300, extend so as to be exposed in this through hole 32, and the individual lead electrode 91, the common lead electrode, and the wiring board 110 are electrically connected in the through hole 32. As such a protection substrate 30, for example, a silicon substrate, a glass substrate, an SOI substrate, various ceramic substrates, etc. are used in the same manner as the flow path forming substrate 10.

[0031] Further, on the protective substrate 30, a case member 40 that defines a part of the manifold 100 communicating with the plurality of pressure chambers 12 is fixed. The case member 40 has substantially the same shape as the above-described communication plate 15 in plan view, is joined to the protective substrate 30, and is also joined to the above-described communication plate 15. Such a case member 40 has a recess 41 on the protective substrate 30 side with a depth in which the flow path forming substrate 10 and the protective substrate 30 are accommodated. Further, the case member 40 is provided with a third manifold portion 42 that communicates with the first manifold portion 17 of the communication plate 15. Then, the first manifold portion 17 and the second manifold portion 18 provided on the communication plate 15 and the third manifold portion 42 provided on the case member 40 constitute the manifold 100 of the present embodiment. The manifold 100 is provided for each nozzle row. That is, different types of ink can be ejected for each nozzle row. Further, the case member 40 is provided with an inlet 44 that communicates with the manifold 100 and supplies ink to each manifold 100. Further, the case member 40 is provided with a connection port 43 that communicates with the through hole 32 of the protective substrate 30 and through which the wiring substrate 110 is inserted, and the wiring substrate 110 is led out to the surface side facing the -Z direction of the liquid ejection head H through the connection port 43. As the case member 40, for example, a metal material, a resin material, or the like can be used.

[0032] Further, a compliance substrate 45 is provided on the surface on the +Z direction side where the first manifold portion 17 and the second manifold portion 18 of the communication plate 15 open. The compliance substrate 45 seals the openings on the +Z direction side of the first manifold portion 17 and the second manifold portion 18. In the present embodiment, such a compliance substrate 45 includes a sealing film 46 made of a flexible thin film and a fixed substrate 47 made of a hard material such as metal. An opening 48 that is completely removed in the thickness direction is provided in the region of the fixed substrate 47 facing the manifold 100, and one surface of the manifold 100 is a compliance portion 49 that is a flexible portion sealed only by the flexible sealing film 46.

[0033] In such a liquid injection head H, liquid is taken in from the inlet 44, and the inside of the flow path from the manifold 100 to the nozzle 21 is filled with ink. Then, in accordance with a signal from the drive signal selection circuit 111, a voltage is applied to each active part 310 corresponding to the pressure chamber 12, thereby causing the diaphragm 50 to deflect and deform together with the piezoelectric actuator 300. As a result, the pressure of the liquid in the pressure chamber 12 increases, and droplets are ejected from a predetermined nozzle 21.

[0034] Also, as shown in FIG. 1, the liquid injection device 1 includes a control unit 4. Here, the electrical configuration of the liquid injection device 1 of the present embodiment will be described with reference to FIGS. 4 and 5. Note that FIG. 4 is a block diagram showing the electrical configuration of the liquid injection device 1 of the present embodiment. FIG. 5 is a block diagram showing the functional realization part of the control unit 4.

[0035] As shown in FIG. 4, the liquid injection device 1 includes a control unit 4 which is a control part of the present embodiment, a print engine 220, and an operation panel 9.

[0036] The control unit 4 is an element that controls the entire liquid injection device 1. The control unit 4 includes a control processing part 211 configured to include a CPU or the like, a storage part 212, a drive signal generation part 213, an external I / F (interface) 214, and an internal I / F 215. Further, the storage part 212 includes a ROM that records a control program and the like, and a RAM that temporarily records various data necessary for printing an image. The control processing part 211 comprehensively controls each element of the liquid injection device 1 by executing the control program recorded in the storage part 212.

[0037] Print data indicating an image to be printed on the medium S is transmitted from an external device 230 such as a host computer to the external I / F 214 of the control unit 4, and the print engine 220 is connected to the internal I / F 215. The print engine 220 is an element that records an image on the medium S under the control of the control unit 4, and includes a liquid injection head H, a conveyance mechanism 5, and a movement mechanism 6.

[0038] The control unit 4 has functions as an injection control unit 240 that injects liquid, an aging processing unit 241 that performs aging processing, and a correspondence relationship information acquisition unit 242.

[0039] The injection control unit 240 controls the injection of droplets from the nozzles 21. Specifically, the control processing unit 211 converts the print data transmitted from the external device 230 to the external I / F 214 into head control signals that instruct the injection / non-injection of droplets from each nozzle 21 of the liquid injection head H for each active unit 310, for example, a clock signal CLK, a latch signal LAT, a change signal CH, pixel data SI, setting data SP, etc., and transmits it to the liquid injection head H via the internal I / F 215. Further, the drive signal generation unit 213 generates a drive signal (COM) and transmits it to the liquid injection head H via the internal I / F 215. That is, injection data such as head control data and drive signals is transmitted to the liquid injection head H via the internal I / F 215, which is a transmission unit.

[0040] The liquid injection head H supplied with injection data such as head control signals and drive signals from the control unit 4 generates an applied pulse from the head control signal and the drive signal, and applies the applied pulse to the active unit 310.

[0041] Also, the control processing unit 211 generates movement control signals for the conveyance mechanism 5 and the movement mechanism 6 from the print data received from the external device 230 via the external I / F 214, and transmits them to the conveyance mechanism 5 and the movement mechanism 6 via the internal I / F 215 to control the conveyance mechanism 5 and the movement mechanism 6. Thereby, printing on the medium S is executed.

[0042] Here, an example of a drive signal for injecting ink droplets will be described with reference to FIG. 6. FIG. 6 is a waveform diagram showing the drive signal of the present embodiment.

[0043] The drive signal (COM) generated by the drive signal generation unit 213 has a drive pulse for injecting ink droplets from the nozzle 21 within one recording period T (frequency 1 / T).

[0044] As shown in the figure, the drive pulse DP is supplied to the first electrode 60, which is an individual electrode, with the second electrode 80, which is a common electrode of the plurality of active portions 310, as the reference potential (Vbs). That is, the voltage applied to the first electrode 60 by the drive waveform is shown as the potential with respect to the reference potential (Vbs).

[0045] Specifically, the drive pulse DP includes an expansion element P1, an expansion maintenance element P2, a contraction element P3, a contraction maintenance element P4, and an expansion return element P5 in this order.

[0046] The expansion element P1 applies a voltage from the intermediate potential Vm to the first potential V1 while the intermediate potential Vm is applied, and expands the volume of the pressure chamber 12 from the reference volume. When the meniscus of the ink formed in the nozzle 21 is drawn toward the pressure chamber 12 by the expansion element P1, ink is supplied from the manifold 100 side to the pressure chamber 12.

[0047] The expansion maintenance element P2 maintains the volume of the pressure chamber 12 expanded by the expansion element P1 for a certain period of time.

[0048] The contraction element P3 applies a potential difference Vh from the first potential V1 to the second potential V2 to contract the volume of the pressure chamber 12. The volume of the pressure chamber 12 is rapidly contracted by the contraction element P3, and the ink in the pressure chamber 12 is pressurized and ejected as ink droplets from the nozzle 21.

[0049] The contraction maintenance element P4 maintains the volume of the pressure chamber 12 contracted by the contraction element P3 for a certain period of time.

[0050] The expansion return element P5 expands and returns the pressure chamber 12 from the contracted state of the second potential V2 to the reference volume of the intermediate potential Vm. The expansion return element P5 supplies at the timing when the pressure of the ink in the pressure chamber 12 decreased by the contraction element P3 rises again due to the natural vibration of the meniscus in the contraction maintenance element P4. By supplying the expansion return element P5 at such a timing, the pressure fluctuation of the ink in the pressure chamber 12 is absorbed.

[0051] The correspondence information acquisition unit 242 acquires correspondence information indicating the correspondence between the driving time of the active part 310 and the driving reduction amount.

[0052] Here, for example, when the driving time for driving the active part 310, which is a driving element, in the aging process is changed in 0.5-hour (0.5 hrs) increments from 0 hour (0 hrs) to 2.5 hours (2.5 hrs), FIG. 7 shows an example of the relationship between the voltage application time and the driving change rate when the active part 310 is continuously driven after the aging process.

[0053] In FIG. 7, the driving change rate is shown as a parameter corresponding to the driving reduction amount. The driving change rate is a ratio calculated as (displacement amount after driving - initial displacement amount) / initial displacement amount, where the displacement amount at the start of driving is the initial displacement amount and the displacement amount after applying voltage for a certain driving time is the displacement amount after driving. As described above, the displacement amount of the active part 310 decreases as it is driven, so the displacement amount after voltage application is smaller than the displacement amount at the start of driving. Therefore, as shown in FIG. 7, the driving change rate has a negative value. On the other hand, the driving reduction amount is for representing the magnitude of the reduction in driving in absolute value, and can be calculated as the initial displacement amount - displacement amount after driving. Whether it is the driving reduction amount or the driving change rate, they are both for indicating how much the displacement amount has decreased.

[0054] As shown in Fig. 7, when the aging treatment time is shorter, the driving element is less stable, so the change in the initial driving reduction amount is larger. For example, when the aging time is 2.5 hrs, the driving change rate is larger than -3.0% during the voltage application time from 0 hrs to 200 hrs. Therefore, the change in the driving change rate is slightly larger than -0.015% / hrs, and it can be seen that the change in the driving change rate is large (the absolute value of the change in the driving change rate is small, and the change in the driving reduction amount is small). On the other hand, when the aging time is 0.5 hrs, the driving change rate is slightly smaller than -4.0% during the voltage application time from 0 hrs to 200 hrs. Therefore, the change in the driving change rate is slightly smaller than -0.020% / hrs, and it can be seen that the change in the driving change rate is small (the absolute value of the change in the driving change rate is large, and the change in the driving reduction amount is large).

[0055] Here, as can be seen from Fig. 7, regardless of the value of the driving time during the aging treatment, the longer the voltage application time, the smaller the driving change rate (the larger the driving reduction amount) for the active part 310. However, the change in the driving change rate becomes gentle after the voltage application time has been long to a certain extent. That is, it can be seen that most of the contribution to the variation in the ejection characteristics is at the initial stage of driving. And also from Fig. 7, it can be seen that the driving change rate at the initial stage of driving varies greatly depending on the aging time. From this, it can be seen that the variation in the ejection characteristics can be controlled by adjusting the driving change rate at the initial stage of driving through the aging treatment.

[0056] Next, the correspondence information will be described. The driving change rate has a correlation with the driving time and driving conditions (voltage, temperature). That correlation is obtained by the function shown in the following formula (1). In formula (1), dr represents the above-mentioned driving change rate. [Equation 1] dr = αLn(t) + β (1)

[0057] Ln(t) in Equation (1) is a value obtained based on the driving time, and α and β are values obtained experimentally. An example of these α and β is shown in Table Ta1 of FIG. 8. As shown in Table Ta1, α and β also change depending on the temperature of the active part 310, and more specifically, the voltage condition of the driving waveform indicating the driving signal supplied to the active part 310. In this embodiment, it is the intermediate potential Vm.

[0058] Such a driving change rate (dr) becomes smaller as the temperature of the active part 310 increases, and becomes larger as the temperature of the active part 310 decreases. In other words, the driving reduction amount becomes larger as the temperature of the active part 310 increases, and becomes smaller as the temperature of the active part 310 decreases.

[0059] Therefore, the driving conditions of the active part 310 include the temperature condition indicating the temperature of the active part 310. Note that the temperature of the active part 310 is substantially the temperature of the liquid ejection head H, and can be obtained, for example, by a temperature sensor such as a thermistor provided in the liquid ejection head H, or a temperature sensor that can non-contact measure the surface temperature of the liquid ejection head H. Also, the correspondence information is such that the driving change rate becomes smaller (the driving reduction amount becomes larger) as the temperature of the active part 310 increases.

[0060] Similarly, the driving change rate (dr) becomes smaller as the voltage applied to the active part 310 increases, and becomes larger as the voltage applied to the active part 310 decreases. In other words, the driving reduction amount becomes larger as the voltage applied to the active part 310 increases, and becomes smaller as the voltage applied to the active part 310 decreases.

[0061] Therefore, the driving conditions of the active part 310 include the voltage condition indicating the voltage of the driving waveform applied to the active part 310. Here, the voltage condition indicating the voltage of the driving waveform includes, for example, the intermediate potential Vm of the driving waveform indicating the driving signal, which will be described in detail later. Note that the voltage condition is not limited to the intermediate potential Vm, and may be the potential difference Vh, which will be described in detail later. Also, the driving change rate becomes smaller (the driving reduction amount becomes larger) as the voltage of the driving waveform applied to the active part 310 increases.

[0062] In this way, the drive change rate is a value that depends on the drive time, temperature, and voltage. That is, if the temperature and voltage are known, it is possible to know what drive change rate will result for a given drive time. Also, the extent to which the lifespan decreases depending on the drive time is determined. Therefore, if the temperature and voltage are known, the user is presented with a combination of the degree of variation in the ejection characteristics (inferred from the drive change rate) and the lifespan decrease, which are in a trade-off relationship, and the user is allowed to select a desired combination from among them. By performing the aging process for only the drive time corresponding to the selected combination, the degree of variation in the ejection characteristics and the lifespan decrease can be adjusted to those desired by the user. One or more pieces of information indicating the correspondence relationship among this voltage, temperature, drive time, drive change rate (drive decrease amount), and lifespan decrease are the correspondence relationship information in this embodiment.

[0063] A specific algorithm of this embodiment will be described. The correspondence relationship information acquisition unit 242 selectively acquires one correspondence relationship from among a plurality of correspondence relationships between the drive time and the drive change rate according to the drive conditions of the active part 310. That is, the correspondence relationship information acquisition unit 242 selects one two-dimensional table that matches the drive conditions from a plurality of two-dimensional tables showing the correspondence relationships among the drive time, drive change rate, and lifespan decrease for different drive conditions of temperature and voltage, for example, the tables Ta2 to Ta4 shown in FIGS. 9 to 11, and acquires one piece of correspondence relationship information from the selected two-dimensional table. In FIGS. 9 to 11, as an example, two-dimensional tables showing the correspondence relationships among the drive time, drive change rate, and lifespan decrease in three cases where the intermediate potential Vm is 7.5V and the temperature is 25°C, the intermediate potential Vm is 8.5V and the temperature is 25°C, and the intermediate potential Vm is 7.5V and the temperature is 45°C are described, but actually, two-dimensional tables of the said correspondence relationships in other combinations of the intermediate potential Vm and temperature are also used. Also, although the drive change rate (dr) is shown in the tables Ta2 to Ta4, it is not limited to this. Also, the lifespan decrease rate shown in the tables Ta2 to Ta4 is the change rate of the lifespan with respect to the lifespan of the active part 310 when the aging process is not performed.

[0064] In addition, the correspondence information acquisition unit 242 is not limited to selecting one two-dimensional table that meets the driving conditions from a plurality of two-dimensional tables to acquire the correspondence information. For example, the correspondence information may be selected from a four-dimensional table, or the correspondence information may be acquired by calculation using a function.

[0065] Such a two-dimensional table is displayed on the display device 9a, and receives the user's instructions by the user operating the operating device 9b.

[0066] Note that it is preferable to store the correspondence information in an external memory provided outside the liquid ejecting apparatus 1, and the correspondence information acquisition unit 242 acquires the correspondence information from the external memory. Examples of the external memory include a storage medium physically connected to the liquid ejecting apparatus 1, and a server connected to the liquid ejecting apparatus 1 via a network such as the Internet or a public telephone line network. Of course, the correspondence information is not limited to being stored in the external memory. For example, the correspondence information may be stored in the storage unit 212 of the liquid ejecting apparatus 1, and the correspondence information acquisition unit 242 may acquire the correspondence information from the storage unit 212.

[0067] The aging processing unit 241 performs aging processing to reduce the driving amount of the active unit 310 by driving the active unit 310 based on the correspondence information acquired by the correspondence information acquisition unit 242. Note that the function as the aging processing unit is realized by the control processing unit 211, the drive signal generation unit 213, etc. in the same manner as the injection control unit 240 described above. In the present embodiment, the aging processing unit 241 drives the active unit 310 with the same drive signal as the drive signal (COM) used for ejecting ink droplets to perform aging processing. Of course, the aging processing unit may drive the active unit 310 using a drive signal having an aging dedicated drive waveform different from the drive signal (COM) used for ejecting ink droplets.

[0068] In addition, the voltage condition of the drive waveform, which is the drive condition of the active part 310 described above, includes the intermediate potential Vm in the drive waveform indicating the drive signal (COM). Further, the voltage condition includes the potential difference Vh in the drive waveform indicating the drive signal (COM). In the present embodiment, the voltage condition is the intermediate potential Vm.

[0069] A driving method using such an aging processing unit 241 will be described with reference to FIGS. 12 to 16. Note that FIG. 12 is a flowchart for explaining the driving method of the liquid ejection device 1. FIGS. 13 to 16 are examples of screens displayed on the display device 9a.

[0070] The aging process is performed before printing. First, in step S1, when the aging process is started, in step S2, as shown in FIG. 13, the control unit 4 causes the display device 9a to display a screen for asking the user whether to use the head manufacturer's recommendation. In step S2, when the user selects to use the head manufacturer's recommendation by operating the operation device 9b (step S2; Yes), in step S3, as shown in FIG. 14, the control unit 4 causes the display device 9a to display a screen on which the user can select the temperature of the active part 310, and the correspondence relationship information acquisition unit 242 acquires the value of the temperature set by the user on the screen using the operation device 9b. Note that in step S3, the user is not limited to setting the temperature of the active part 310 using the operation device 9b. For example, the correspondence relationship information acquisition unit 242 may detect and acquire the temperature of the active part 310 or the temperature of the liquid ejection head H using a temperature sensor or the like provided in the liquid ejection head H.

[0071] Next, in step S4, as shown in FIG. 15, the control unit 4 causes the display device 9a to display a screen on which the user can set the voltage of the active part 310, and the correspondence relationship information acquisition unit 242 acquires the value of the voltage set by the user on the screen using the operation device 9b. Note that in step S4, the user is not limited to setting the voltage of the active part 310 using the operation device 9b. For example, the correspondence relationship information acquisition unit 242 may automatically detect and acquire the voltage from the drive signal indicating the drive waveform supplied to the active part 310.

[0072] Next, in step S5, the correspondence information acquisition unit 242 acquires the correspondence information between the aging time and the degradation level that matches the temperature and voltage acquired in steps S3 and S4. In step S6, as shown in FIG. 16, the control unit 4 displays the two-dimensional table showing the correspondence information that allows the user to set the aging conditions, Table Ta2 in this embodiment as an example, on the display device 9a. Next, in step S7, as shown in FIG. 16, the correspondence information acquisition unit 242 accepts the user's selection of the aging conditions set by the user using the operation device 9b. In the example shown in FIG. 16, the user selects that when the driving time is 1.5 hours and the aging process is not performed, the change rate with respect to the driving change rate when repeatedly driving is -1.2%, and the life reduction rate with respect to the life when repeatedly driving without performing the aging process is -0.03%. Next, in step S8, the aging processing unit 241 executes the aging process based on the user's selection, and ends the aging process in step S11.

[0073] Note that in step S2, if the user selects not to use the head manufacturer's recommendation using the operation device 9b (step S2; No), in step S9, the aging processing unit 241 accepts the value set by the user for arbitrary aging conditions. In step S10, the aging processing unit 241 executes the aging process based on the aging conditions set by the user in step S9, and ends the aging process in step S11.

[0074] As described above, in the liquid ejecting apparatus 1 of the present embodiment, the aging process can be flexibly performed according to the user's requirements. As described above, when the driving time of the aging process is increased in the active portion 310, the amount of driving reduction when continuously used for printing thereafter becomes large, but the lifespan becomes short. On the other hand, when the driving time of the aging process is decreased, the lifespan when continuously used for printing thereafter becomes long, but the amount of driving reduction becomes small. That is, there is a trade-off relationship between suppressing the variation in ejection characteristics due to driving reduction and achieving a long lifespan. For this reason, if a head manufacturer that manufactures the liquid ejection head H provides the user who manufactures the liquid ejecting apparatus 1 with a liquid ejection head H that has undergone a predetermined aging process, there is a risk of providing a liquid ejection head H that does not meet the user's requirements. That is, there is a risk of problems such as providing a liquid ejection head H that has undergone an aging process aimed at a long lifespan by the head manufacturer to a user who emphasizes suppressing the variation in ejection characteristics, or providing a liquid ejection head H that has undergone an aging process aimed at suppressing the variation in ejection characteristics by the head manufacturer to a user who emphasizes a long lifespan. In the present embodiment, with the liquid ejection head H mounted on the liquid ejecting apparatus 1, the aging process can be executed according to the user's requirements, such as whether to emphasize suppressing the variation in ejection characteristics during printing or to emphasize the long lifespan of printing. Therefore, it is possible to suppress the liquid ejection head H provided from not meeting the user's requirements and improve the user's satisfaction.

[0075] In addition, when providing the liquid ejection head H, since the aging process can be performed based on the correspondence information indicating the correspondence relationship between the driving time and the driving change rate according to the characteristics of the liquid ejection head H, the aging process that meets the user's requirements can be easily executed.

[0076] Also, in the present embodiment, when providing the liquid ejection head H, aging processing can be performed based on the correspondence information indicating the correspondence between the driving time and the driving change rate of the active part 310 when the provided liquid ejection head H is mounted on the liquid ejection device 1, that is, the correspondence according to the temperature and voltage conditions. That is, even if the driving conditions of the liquid ejection head H provided by the head manufacturer are not grasped, the user side that manufactures the liquid ejection device 1 can determine the driving conditions of the liquid ejection head H and perform aging processing based on the correspondence information optimal for the driving conditions. Therefore, when printing after performing the aging processing, it is possible to suppress variations different from the user's desires and suppress the reduction in life, and to realize the user's desires according to the user's environment.

[0077] (Other embodiments) As described above, each embodiment of the present invention has been described, but the basic configuration of the present invention is not limited to the above-described one.

[0078] For example, in the above-described Embodiment 1, the correspondence information acquisition unit 242 is configured to acquire the correspondence information between the driving time and the driving change rate of the active part 310 and the driving conditions of the active part 310. However, it is not particularly limited thereto, and the correspondence information acquisition unit 242 may be configured to acquire the correspondence information between the driving time and the driving change rate of the active part 310. That is, it is not necessarily required to use the driving conditions of temperature and voltage. Of course, since the driving change rate (driving reduction amount) depends not only on the driving time but also on the temperature and voltage, it is possible to obtain more accurate results if the temperature and voltage are also included in the correspondence as in the above-described embodiment. However, if a certain degree of inaccuracy is allowed, it is possible to allow the user to select which of the ejection characteristic variations and long life, which are in a trade-off relationship, to prioritize in aging based only on the correspondence between the driving time, the driving change rate, and the life reduction rate without using the temperature and voltage.

[0079] In the above-described Embodiment 1, the thin-film piezoelectric actuator 300 has been described as the driving element that causes a pressure change in the pressure chamber 12. However, the present invention is not particularly limited thereto. For example, a thick-film piezoelectric actuator formed by a method such as attaching a green sheet, or a longitudinal vibration type piezoelectric actuator in which a piezoelectric material and an electrode forming material are alternately laminated and expanded and contracted in the axial direction can be used. Since the thick-film type and longitudinal vibration type piezoelectric actuators have the same tendency of correspondence relationship as the thin-film type piezoelectric actuator, the same aging treatment as that in the above-described Embodiment 1 is performed to achieve the same effect. Further, as the driving element, one in which a heating element is disposed in the pressure chamber 12 and droplets are discharged from the nozzle by bubbles generated by the heat generation of the heating element can be used. Even when a heating element is used as the driving element, the same effect can be achieved by applying the present invention.

[0080] Further, in the above-described Embodiment 1, the aging rate was included in the correspondence relationship information. However, it is not necessarily required to include information related to the lifespan. By performing the aging treatment, in addition to the reduction in lifespan, there may be other adverse effects such as a decrease in the discharge amount due to a decrease in the displacement amount itself, or an increase in the load of the electric circuit due to deterioration of the electrical characteristics. Parameters related to those adverse effects may be included in the correspondence relationship information instead of the aging rate. Alternatively, neither the aging rate nor the parameters related to other adverse effects may be included.

[0081] Further, when the aging treatment of Embodiment 1 is performed, driving reduction may occur and the discharge amount may deviate from the desired discharge amount. In that case, the driving waveform may be adjusted according to the driving reduction amount. Alternatively, the driving waveform may be adjusted according to the driving reduction amount calculated in the same manner as in the present embodiment without performing the aging treatment.

[0082] Furthermore, the present invention is directed to liquid ejection devices in general that widely include a liquid ejection head. The liquid ejection head includes, for example, recording heads such as various inkjet recording heads used in image recording devices such as printers, and colorant ejection heads used in the manufacture of color filters such as liquid crystal displays. Also, the liquid ejection head includes, for example, electrode material ejection heads used for forming electrodes in organic EL displays, FED (field emission displays), etc., and bio-organic matter ejection heads used in the manufacture of biochips, etc., and the present invention can also be applied to liquid ejection devices equipped with these liquid ejection heads.

[0083] (Supplementary Note) From the embodiments exemplified above, for example, the following configurations can be understood.

[0084] The liquid ejection device according to Embodiment 1, which is a preferred embodiment, includes a liquid ejection head having a nozzle for ejecting liquid and a driving element, a correspondence relationship information acquisition unit that acquires correspondence relationship information indicating the correspondence relationship between the driving time and the driving reduction amount of the driving element, an aging processing unit that performs aging processing to reduce the driving amount of the driving element by driving the driving element before printing based on the correspondence relationship information, and an ejection control unit that drives the driving element to eject liquid after the aging processing.

[0085] According to this, in the liquid ejection device, aging processing of the liquid ejection head can be executed based on the correspondence relationship information of the liquid ejection head. Therefore, aging processing suitable for the liquid ejection device and the liquid ejection head can be executed in accordance with the user's requirements.

[0086] In Embodiment 2, which is a specific example of Embodiment 1, the correspondence relationship information is defined such that the driving reduction amount increases as the driving time becomes longer.

[0087] In Embodiment 3, which is a specific example of Embodiment 1, the correspondence relationship information indicates the correspondence relationship information among the driving time, the driving reduction amount, and the driving conditions of the driving element. According to this, by using the correspondence relationship information corresponding to the driving conditions of the driving element, an aging process suitable for the driving conditions of the driving element can be executed.

[0088] In Embodiment 4, which is a specific example of Embodiment 3, the driving conditions include temperature conditions indicating the temperature of the driving element. According to this, an aging process suitable for the temperature of the driving element can be executed.

[0089] In Embodiment 5, which is a specific example of Embodiment 4, the correspondence relationship information is determined such that the driving reduction amount increases as the temperature increases.

[0090] In Embodiment 6, which is a specific example of Embodiment 3, the driving conditions include voltage conditions indicating the voltage of the driving waveform applied to the driving element. According to this, an aging process suitable for the voltage conditions of the driving element can be executed.

[0091] In Embodiment 7, which is a specific example of Embodiment 6, the correspondence relationship information is determined such that the driving reduction amount increases as the voltage increases.

[0092] In Embodiment 8, which is a specific example of Embodiment 3, the correspondence relationship information acquisition unit selectively acquires one correspondence relationship from a plurality of correspondence relationships between the driving time and the driving reduction amount according to the driving conditions of the driving element. According to this, a correspondence relationship suitable for the driving conditions can be easily selected from among the plurality of correspondence relationships.

[0093] In Embodiment 9, which is a specific example of Embodiment 1, it further includes a display unit that displays the correspondence relationship information and a reception unit that receives a user's instruction regarding the displayed correspondence relationship information, and the aging process unit performs an aging process according to the received user's instruction. According to this, an aging process suitable for the liquid ejection head can be executed according to the user's requirements.

[0094] In Embodiment 10, which is a specific example of Embodiment 1, the correspondence relationship information acquisition unit acquires the correspondence relationship information from an external memory provided outside the liquid ejection device. According to this, the correspondence relationship information acquisition unit can easily acquire the correspondence relationship information.

[0095] A driving method for a liquid ejection device according to Embodiment 11, which is a preferred embodiment, is a driving method for a liquid ejection device including a liquid ejection head having a nozzle for ejecting a liquid and a driving element, the method including acquiring correspondence relationship information indicating a correspondence relationship between a driving time of the driving element and a driving reduction amount, and performing an aging process of reducing a driving amount of the driving element by driving the driving element before printing based on the acquired correspondence relationship information.

[0096] According to this, in the liquid ejection device, an aging process of the liquid ejection head can be executed based on the correspondence relationship information of the liquid ejection head. Therefore, an aging process suitable for the liquid ejection device and the liquid ejection head can be executed according to the user's requirements.

[0097] In Embodiment 12, which is a specific example of Embodiment 11, the correspondence relationship information is defined such that the driving reduction amount increases as the driving time becomes longer.

[0098] In Embodiment 13, which is a specific example of Embodiment 11, the correspondence relationship information indicates the correspondence relationship information between the driving time, the driving reduction amount, and the driving conditions of the driving element. According to this, by using the correspondence relationship information corresponding to the driving conditions of the driving element, an aging process suitable for the driving conditions of the driving element can be executed.

[0099] In Embodiment 14, which is a specific example of Embodiment 13, the driving conditions include a temperature condition indicating the temperature of the driving element. According to this, an aging process suitable for the temperature of the driving element can be executed.

[0100] In Embodiment 15, which is a specific example of Embodiment 14, the correspondence relationship information is defined such that the driving reduction amount increases as the temperature becomes higher.

[0101] In Embodiment 16, which is a specific example of Embodiment 13, the driving conditions include voltage conditions indicating the voltage of the driving waveform applied to the driving element. According to this, an aging process suitable for the voltage conditions of the driving element can be executed.

[0102] In Embodiment 17, which is a specific example of Embodiment 16, the correspondence relationship information is determined such that the driving reduction amount increases as the voltage increases.

Explanation of Reference Numerals

[0103] H... Liquid ejection head, S... Medium, 1... Liquid ejection device, 2... Housing, 3... Liquid storage section, 4... Control unit, 5... Conveying mechanism, 5a... Conveying roller, 6... Moving mechanism, 7... Holding body, 8... Conveying belt, 9... Operation panel, 9a... Display device, 9b... Operating device, 10... Flow path forming substrate, 12... Pressure chamber, 15... Communication plate, 16... Nozzle communication path, 17... First manifold section, 18... Second manifold section, 19... Supply communication path, 20... Nozzle plate, 21... Nozzle, 30... Protection substrate, 31... Accommodation section, 32... Through hole, 40... Case member, 41... Recess, 42... Third manifold section, 43... Connection port, 44... Introduction port, 45... Compliance substrate, 46... Sealing film, 47... Fixed substrate, 48... Opening, 49... Compliance section, 50... Diaphragm, 51... Elastic film, 52... Insulator film, 60... First electrode, 70... Piezoelectric layer, 80... Second electrode, 91... Individual lead electrode, 100... Manifold, 110... Wiring substrate, 111... Driving signal selection circuit, 211... Control processing section, 212... Storage section, 213... Driving signal generation section, 220... Print engine, 230... External device, 240... Injection control section, 241... Aging processing section, 242... Correspondence relationship information acquisition section, 300... Piezoelectric actuator, 310... Active section.

Claims

1. A liquid injection device comprising a nozzle for injecting a liquid and a liquid injection head provided with a drive element, a correspondence information acquisition unit for acquiring correspondence information indicating a correspondence between a drive time of the drive element and a drive reduction amount, an aging processing unit for performing aging processing to reduce the drive amount of the drive element by driving the drive element before printing based on the correspondence information, and an injection control unit for driving the drive element to inject a liquid after the aging processing. The liquid injection device is characterized by the above.

2. The correspondence information is determined such that the drive reduction amount increases as the drive time increases. The liquid injection device according to claim 1, characterized by the above.

3. The correspondence information indicates the correspondence information between the drive time, the drive reduction amount, and the drive conditions of the drive element. The liquid injection device according to claim 1, characterized by the above.

4. The drive conditions include temperature conditions indicating the temperature of the drive element. The liquid injection device according to claim 3, characterized by the above.

5. The correspondence information is determined such that the drive reduction amount increases as the temperature increases. The liquid injection device according to claim 4, characterized by the above.

6. The drive conditions include voltage conditions indicating the voltage of the drive waveform applied to the drive element. The liquid injection device according to claim 3, characterized by the above.

7. The correspondence information is determined such that the drive reduction amount increases as the voltage increases. The liquid injection device according to claim 6, characterized by the above.

8. The correspondence information acquisition unit selectively acquires one correspondence from a plurality of correspondences between the drive time and the drive reduction amount according to the drive conditions of the drive element. The liquid injection device according to claim 3, characterized by the above.

9. The liquid injection device further includes a display unit for displaying the correspondence information, and a reception unit for receiving a user's instruction for the displayed correspondence information. The aging processing unit performs aging processing according to the received user's instruction. The liquid injection device according to claim 1, characterized by the above.

10. The correspondence information acquisition unit acquires the correspondence information from an external memory provided outside the liquid injection device. The liquid injection device according to claim 1, characterized by the above.

11. A driving method for a liquid injection device including a liquid injection head provided with a nozzle for injecting a liquid and a drive element, ​ Obtain correspondence information indicating the correspondence between the driving time of the driving element and the driving reduction amount, and based on the obtained correspondence information, perform aging processing to reduce the driving amount of the driving element by driving the driving element before printing. A driving method for a liquid ejection device, characterized by the above.

12. The correspondence information is determined such that the driving reduction amount increases as the driving time becomes longer. A driving method for a liquid ejection device according to claim 11, characterized by the above.

13. The correspondence information indicates the correspondence information between the driving time, the driving reduction amount, and the driving conditions of the driving element. A driving method for a liquid ejection device according to claim 11, characterized by the above.

14. The driving conditions include temperature conditions indicating the temperature of the driving element. A driving method for a liquid ejection device according to claim 13, characterized by the above.

15. The correspondence information is determined such that the driving reduction amount increases as the temperature becomes higher. A driving method for a liquid ejection device according to claim 14, characterized by the above.

16. The driving conditions include voltage conditions indicating the voltage of the driving waveform applied to the driving element. A driving method for a liquid ejection device according to claim 13, characterized by the above.

17. The correspondence information is determined such that the driving reduction amount increases as the voltage becomes higher. A driving method for a liquid ejection device according to claim 16, characterized by the above.

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