JP2006281454A - Liquid droplet delivering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid droplet delivering apparatus which can ensure fluidity of a liquid material while the liquid material is prevented from being deteriorated when the liquid material is delivered. <P>SOLUTION: The time for cooling naturally the liquid material in a tube 12 is calculated in advance, and the heating temperature by a heater 60 is controlled in accordance with the time. Namely, when the calculated time is short, heating is performed by setting the heating temperature low as lowering in temperature by natural cooling is small, and when the calculated time is long, heating is performed by setting the heating temperature high as lowering in temperature by natural cooling is large. It is possible thereby to bring the temperature of the liquid material reaching a head high without always continuously heating the liquid material, and as the viscosity of the liquid material can be kept at a high condition, it becomes possible to ensure the fluidity of the liquid material while the liquid material is prevented from being deteriorated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a droplet discharge device.

2. Description of the Related Art In recent years, an ink jet method (droplet discharge method) is known as a method for forming a wiring pattern formed on an electro-optical device or the like or a pattern such as a light emitting portion formed on a substrate for an organic EL device. The ink jet method is a printing technique used in a so-called ink jet printer, and ejects ink droplets filled in an ejection head of an ink jet apparatus (droplet ejection apparatus) from the ejection head onto a substrate and fixes them. Is.
For example, Patent Document 1 or Patent Document 2 discloses a method of manufacturing an organic EL (electroluminescence) device using such an ink jet method.
Japanese Patent Laid-Open No. 11-54270 JP 2004-1227897 A

The viscosity of the ink can be raised as an important parameter when patterning is performed by selective ejection using such an ink jet method. When discharging by the ink jet method, conditions such as power and time for driving the discharge head are optimized in accordance with characteristics such as viscosity and elastic modulus of the ink to be used. Here, if the ink viscosity changes, the ink droplet discharge weight may fluctuate, and a desired film thickness may not be obtained, or the discharge itself may be impossible.
Further, in order to obtain a uniform film thickness, the drying conditions (temperature, pressure, etc.) of the ink ejected by the ink jet method are also optimized. However, when the viscosity of the ink changes, the distribution of film thickness at the time of drying is also affected, and it becomes difficult to stably obtain a uniform film thickness.
Furthermore, when the material used for the functional layer of the organic EL device is converted to ink, the viscosity changes with time after the ink preparation often occurs. Such a change in ink viscosity over time causes a change in the thickness of the formed organic functional layer, which makes it difficult to stably form an organic EL device by an ink jet method. Furthermore, depending on the combination of the material used (light emitting material, hole injection material, interlayer material, etc.) and the solvent, the ink viscosity changes with time, making it difficult to apply to film formation by the ink jet method.

  In view of the circumstances as described above, an object of the present invention is to expand the range of selection of materials and solvents by dealing with the increase in ink viscosity over time in the ink jet method. It is another object of the present invention to provide a droplet discharge apparatus and a droplet discharge method that realize stable discharge and high process reproducibility. It is another object of the present invention to provide a droplet discharge device capable of ensuring the fluidity of a liquid material while preventing the deterioration of the liquid material when discharging the liquid material.

  In order to achieve the above object, a droplet discharge device according to the present invention includes a head for holding a liquid material, a head for discharging the held liquid material, and a flow path for supplying the liquid material to the head. Means, a flow path heating unit provided in the flow path at a predetermined distance from the head and capable of heating the flow path, and data on the flow rate of the liquid material flowing in the flow path And a control unit that controls the heating temperature of the flow path heating unit.

  In the present invention, the liquid material is heated via the flow path by the flow path heating unit. The liquid material can be returned to the original viscosity of the liquid material (the state before the thickening starts) before being discharged from the head by being heated by the flow path heating unit. Will be able to do.

  At this time, if the flow rate of ink is large, the effective heating time is short, and if the flow rate is small, the effective time is long. If the effective heating time is shortened, the heat treatment becomes insufficient and the liquid material cannot be returned to its original viscosity. On the other hand, when the effective heating time is long, the heat treatment becomes excessive, which may cause deterioration of the liquid material. For this reason, by controlling the heating temperature of the flow path heating unit based on the data relating to the flow velocity of the liquid material flowing in the flow path, it is possible to supply a liquid material having a stable viscosity and no deterioration to the ejection head.

  In addition, the apparatus further includes a storage unit that stores data relating to the flow rate, and the control unit controls ejection of the liquid material, and the liquid material is heated in the flow path using the predetermined distance and the flow rate. It is preferable that an arrival time from the position where the part is provided to reach the head is calculated, and the heating temperature of the flow path heating unit is controlled according to the calculated length of the arrival time.

  According to the present invention, the elapsed time until the liquid material passes through the flow path heating section at a predetermined flow rate is calculated, and the heating temperature in the flow path heating section is controlled according to the time. That is, when the calculated time is short, the heat treatment may be insufficient, and thus the heating temperature is controlled to be high. Further, when the calculated time is long, it can be considered that the heat treatment becomes excessive, and the heating temperature is controlled to be low.

  In addition, the apparatus further includes a storage unit that stores data relating to the flow rate, and the control unit controls ejection of the liquid material, and the liquid material is heated in the flow path using the predetermined distance and the flow rate. It is preferable to calculate a required time for passing through the section and control a heating temperature of the flow path heating unit according to the calculated length of the required time.

  According to the present invention, the time required for the liquid material to pass through the flow path heating unit at a predetermined flow rate is calculated, and the heating temperature in the flow path heating unit is controlled according to the time. That is, when the calculated time is short, the heat treatment may be insufficient, and thus the heating temperature is controlled to be high. Further, when the calculated time is long, it can be considered that the heat treatment becomes excessive, and the heating temperature is controlled to be low. Here, the “required time” refers to the time until the thickening starts (changes to the problematic viscosity), and is proportional to the arrival time from the flow path heating unit to the head.

The head further comprises a head heating unit capable of heating the head, and the control unit is configured to store the liquid material so that the flow path and the head are heated when the liquid material is dummy-discharged. It is preferable to control the flow path heating unit and the head heating unit so that the flow path is heated and the head is not heated when discharging.
According to the present invention, when performing dummy discharge, not only the flow path but also the head is heated, so that even if the liquid material is thickened, it is possible to prevent occurrence of defective discharge and ensure dummy discharge. It can be performed.

  In addition, the storage unit further stores data relating to a time required for the liquid material to be heated by the flow path heating unit to return to the original viscosity in the flow path after the viscosity is reduced, and the control unit Determining whether the elapsed time since the liquid material was heated exceeds the required time, determining whether the liquid material has already been dummy ejected, and the elapsed time exceeds the required time When it is determined that the liquid material is not discharged by dummy, the flow path heating unit and the head heating unit are controlled so that the flow path and the head are heated, and the liquid material is discharged by dummy discharge. When the head is controlled so that the elapsed time exceeds the required time, and it is determined that the liquid material has already been dummy ejected, the flow path is heated to With de is controlling the flow heating unit and the head heating part so as not to be heated, the liquid material is preferably configured to control the head as the ejection.

  The time required from the start of heating by the flow path heating unit to the holding by the head may be measured in advance, for example, by performing an experiment under the same conditions as those of the droplet discharge device according to the present invention. However, the time actually required when using the droplet discharge device may be stored. Further, an average of these times may be taken and the average value may be designed to be a required time.

  In the present invention, the required time can be set as a threshold, and when the elapsed time exceeds the threshold, it can be considered that a liquid material sufficient for ejection is held in the head. In addition, the dummy discharge is a trial hit in order to stably discharge the liquid material during the main discharge, so it is necessary to perform the dummy discharge before the main discharge. In the present invention, since the main discharge is controlled after the dummy discharge is performed, the liquid material is stably discharged during the main discharge.

  Note that the dummy discharge corresponds to the amount of liquid material in the flow path from the heating unit to the head. From this, if the elapsed time exceeds a certain time, the liquid material may be thickened, and the discharge is unstable due to the thickening effect by performing dummy discharge while heating the head The liquid material that is likely to become can be removed reliably. Further, when the viscosity is not increased, it is possible to suppress a decrease in the use efficiency of the liquid material by controlling so as not to perform heating or dummy discharge.

(First embodiment)
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment according to the invention will be described with reference to the drawings.
FIG. 1 is a perspective view schematically showing an overall configuration of a droplet discharge device 1 of the present invention.
As shown in FIG. 1, the droplet discharge device 1 is mainly configured by a base 2, a substrate stage 3, a discharge mechanism 4, and a control unit 5. The droplet discharge device 1 discharges a liquid material containing, for example, a light emitting material toward an organic EL device substrate (hereinafter referred to as “substrate” in the present embodiment) S, and patterns a light emitting portion. An apparatus for (droplet discharge method).

  The substrate stage 3 is a holding member that holds the substrate G when the liquid material is discharged onto the substrate G, and is provided at substantially the center of the base 2 in the X direction. The substrate stage 3 is formed with a through hole 3a and a through hole 3b penetrating the substrate stage 3. The through hole 3a and the through hole 3b are communicated with a pressure adjusting device (not shown) such as a pump mechanism, for example. ing. The pressure adjusting device operates to suck air in the vicinity of the through hole 3a and the through hole 3b, so that the substrate G is adsorbed and held on the substrate stage 3 through the through hole 3a and the through hole 3b. It has come to be.

  The substrate stage 3 is attached to a stage support column 8 of a moving mechanism 7 having a guide rail 6 (extending in the Y direction on the base 2). The stage support column 8 is fixed to a slider 9, and the slider 9 moves on the guide rail 6 in the form of a linear motor, for example. As the slider 9 moves on the guide rail 6 in the Y direction, the substrate stage 3 moves in the Y direction. The slider 9 is provided with a direct drive motor (not shown) for rotating the slider 9 in the θ direction. The substrate stage 3 can be indexed (rotation indexed) by rotating the direct drive motor along the θ direction.

  The ejection mechanism 4 includes a head unit 10 that ejects a liquid material toward the substrate G, a tank 11 that stores the liquid material, and a tube 12 that serves as a flow path when the liquid material is supplied from the tank 11 to the head unit 10. And a heater (flow path heating unit) 60 that heats the tube 12 and a heater (head heating unit) 61 that heats the head unit 10.

  The head unit 10 is composed mainly of a head plate 25 and a head 27. A plurality of heads 27 are arranged on the head plate 25 to constitute a so-called multi-head. The head unit 10 is attached to a head support member 16 of a moving mechanism 15 having a guide rail 14 (extending in the X direction on the base 2).

  The moving mechanism 15 is supported above the base 2 (in the Z direction in the figure) by the moving mechanism support member 17, and both ends of the moving mechanism support member 17 are provided at the end portions of the base 2 in the X direction. The column 18 and the support column 19 are respectively supported. The head support member 16 is fixed to a slider 20, and the slider 20 is provided so as to be movable on the guide rail 14 in the form of a linear motor, for example. As the slider 20 moves on the guide rail 14 in the X direction, the head unit 10 moves in the X direction.

The head unit 10 has motors 21, 22, 23, and 24 as swing positioning devices. When the motor 21 is operated, the head unit 10 moves up and down along the Z axis, when the motor 22 is operated, the head unit 10 swings along the β direction around the Y axis, and when the motor 23 is operated, the head unit 10 is moved. The head unit 10 swings in the α direction around the Z axis when it swings in the γ direction around the X axis and the motor 24 is operated. As described above, the moving mechanism 15 supports the head unit 10 so as to be movable in the X direction and the Z direction, and supports the head unit 10 so as to be movable in the α direction, the β direction, and the γ direction.
For example, a pump (not shown) or the like is attached to the tank 11, and the liquid material in the tank 11 is supplied to the tube 12 by changing the internal pressure in the tank 11.

FIG. 2 is an exploded perspective view showing the configuration of the head 27.
The head 27 includes a nozzle plate 30 having nozzles 27 a, a diaphragm 31, a pressure chamber substrate 32, and a housing 33. The pressure chamber substrate 32 includes a cavity 34, a side wall 35, a reservoir 38, and a supply port 39.

  The cavity 34 is a pressure chamber and is formed by etching a substrate such as silicon. The side walls 35 are configured to partition the cavities 34. The reservoir 38 is configured as a common flow path capable of supplying a liquid when the cavities 34 are filled with the liquid. The supply port 39 is configured to be able to introduce liquid into each cavity 34.

  The casing 33 is provided with a tube port 36 for attaching the tube 12 shown in FIG. The tank 11 and the head 27 are communicated with each other via the tube port 36, and the liquid material supplied from the tank 11 is supplied to the head 27. A piezoelectric element 37 is provided at a position corresponding to the cavity 34 on the vibration plate 31. The piezoelectric element 37 has a structure in which a piezoelectric ceramic such as a PZT element is sandwiched between an upper electrode and a lower electrode (not shown). For example, the piezoelectric element 37 is configured to expand toward the diaphragm 31 when an electric signal is supplied from the control unit 5.

  When an electric signal is supplied from the control unit 5 to the piezoelectric element 37 while the liquid material is held in the cavity 34, the piezoelectric element 37 expands toward the diaphragm 31. A force due to expansion is applied, and the diaphragm 31 bites into the cavity 34 side. When the diaphragm 31 bites in, pressure is applied in the cavity 34. Due to this pressure, droplets are ejected from the nozzle 27a.

  Returning to FIG. 1, the heater 60 is attached to the tube 12 at a position away from the head unit 10 by L1 so that the liquid material flowing through the tube 12 can be heated by heating the tube 12. It has become. The heater 60 is attached with a timer 32 that measures the time from the start of heating of the heater 60. The heater 61 is attached to the head unit 10. The liquid material in the head 27 can be heated by heating the head unit 10.

  The timer 32 measures the elapsed time after the heating by the heater 60 is started. Here, for example, the heating start of the heater 60 and the measurement start of the timer 32 are synchronized, and the timer 32 is set to start automatically when the heater 60 starts heating. The timer 32 does not necessarily need to be attached to the heater 60, and may be attached to any part of the droplet discharge device 1, such as the tube 12, or inside the droplet discharge device 1. May be provided independently.

As shown in FIG. 3, the control unit 5 includes a CPU 40, a ROM 41, a RAM 42, an input / output unit 43, a data storage unit 44, and a program storage unit 45.
The CPU 40, the ROM 41, and the RAM 42 are for performing processing / calculation. The input / output unit 43 transmits and receives signals to and from the outside.

  The data storage unit 44 includes flow rate data 46 relating to the flow rate of the liquid material flowing in the tube 12, distance data 47 that is data of the distance L 1 between the heater 60 and the head unit 10, and temperature settings of the heater 60 and the heater 61. The temperature data 48, the time data 49 that is the time required for the liquid material to be held by the head 27 after being heated by the heater 60, and the discharge history data 50 relating to the history of discharge of the liquid material from the head 27 are stored. ing.

  A correlation is recognized between the flow rate of the liquid material flowing through the tube 12 and the discharge amount of the liquid material discharged from the head 27. That is, the flow rate is increased when the discharge amount from the head 27 is large, and the flow rate is decreased when the discharge amount is small. Therefore, the flow rate data 46 can specifically include the discharge amount from the head 27.

For the distance data 47, for example, when the heater 60 is installed in the process of manufacturing the droplet discharge device 1, the length of the tube 12 between the heater 60 and the head unit 10 is measured, and the tube 12 is measured. Can be the distance data 47.
Regarding the temperature data 48, for example, the liquid material is naturally cooled between the heater 60 and the head 27, and the temperature of the liquid material when the liquid material reaches the head 27 is taken into consideration that the temperature is lowered by the natural cooling. Is set to a temperature at which the fluidity can be maintained. If the heating temperature is higher than the glass transition temperature of a polymer material (light emitting material, hole injection / transport material, etc.) used as the solute of the liquid material, the polymer material deteriorates and desired characteristics cannot be obtained. There is a fear. In the present embodiment, as the liquid material, for example, a polymer material having a fluorene skeleton dissolved or dispersed in a benzene-based or biphenyl-based solvent (for example, isopropyl biphenyl, cyclohexylbenzene, dimethyldiphenyl ether) can be used. . This liquid material has a viscosity that changes with time as shown in FIG. FIG. 4 is a graph showing changes in viscosity over time, with the vertical axis indicating viscosity and the horizontal axis indicating time change. Since many of the above-described polymer materials have a glass transition of 150 ° C. to 250 ° C., it is desirable to set the temperature to 120 ° C. or less in consideration of a margin. Further, at a temperature lower than 60 ° C., the effect of returning the liquid material to the original viscosity cannot be obtained, or the processing time until the effect is obtained becomes long, and the operation rate of the droplet discharge device 1 is maintained. Becomes difficult.

  Returning to FIG. 3, regarding the time data 49, the data (elapsed time data) about the time until the liquid material passes through the heater 60 (elapsed time data), and the liquid material is heated by the heater 60 to reduce the viscosity. There is data (time required data) about the time (required time) until the original viscosity is restored. The elapsed time data is data calculated from the distance data 47 and the time data 49. For the required time data, for example, an experiment is performed using an apparatus in which conditions such as the discharge amount and the tube length are the same as the discharge amount of the droplet discharge device 1 and the length of the tube 12 according to the present embodiment. Thus, the time measured in advance may be set as the required time. The time actually required when using the droplet discharge device 1 may be set as the required time. It may be designed such that the average of the time measured in advance or the time actually required is taken and the average value becomes the required time. In addition, when referring to the graph of FIG. 4, the predetermined time is about 40 days.

  In the program storage unit 45, an arrival time calculation unit 51 that calculates an arrival time until the liquid material reaches the head unit 10 from the heater 60, and optimum set temperatures of the heater 60 and the heater 61 are stored from the temperature data 48. It is determined whether the temperature selection unit 52 to be selected and the time after the liquid material in the tube 12 passes through the heater 60 (time measured by the timer 32) exceeds or does not exceed the predetermined time in the time data 49. An elapsed time determination unit 53 and a discharge control unit 54 that performs determination / instruction regarding discharge of the liquid material are included.

  Next, the operation of the droplet discharge device 1 configured as described above will be described with reference to FIGS. Here, a case where a pattern such as a light emitting portion formed on a substrate is formed will be described as an example. In the droplet discharge device 1, dummy discharge is performed in order to stabilize the discharge amount of the liquid material, and then main discharge for forming a pattern such as a light emitting portion is performed. FIG. 5 is a flowchart showing the operation of the droplet discharge device 1. FIG. 6 is a diagram illustrating a state of dummy ejection. FIG. 7 is a diagram illustrating a state of the main discharge.

When the liquid material is filled in the tank 11 and the droplet discharge device 1 is driven, the liquid material flows through the tube 12 at a predetermined flow rate.
The arrival time calculation unit 51 is based on the flow velocity data 46 and the distance data 47, and the time until the liquid material reaches the head unit 10 from the heater 60, that is, the liquid material in the tube 12 is held by the head 27. Is calculated (step 301). The temperature selection unit 52 selects the optimum heating temperature of the heater 60 from the temperature data 48 based on the calculated arrival time (step 302).

  The liquid material heated by the heater 60 is naturally cooled before it reaches the head 27 through the tube 12 and becomes lower than the temperature when heated by the heater 60. If the time (required time) until the thickening starts (changes to the problematic viscosity) is short, the heat treatment is considered to be insufficient, so the heating temperature is controlled to be high. Therefore, the heating temperature is selected to be a high temperature from the range of the temperature data 48. The required time has a proportional relationship with the calculated arrival time. Moreover, when the time until thickening starts is long, it can be considered that the heat treatment becomes excessive, and the heating temperature is controlled to be low. Therefore, the heating temperature is selected to be a low temperature from the range of the temperature data 48. The heater 60 starts heating the tube 12 at the temperature selected by the temperature selection unit 52 (step 303).

With the start of heating by the heater 60, the timer 32 starts timing. The elapsed time determination unit 53 reads the elapsed time measured by the timer 32 and compares it with the required time (threshold value) of the time data 49.
When it is determined that the elapsed time exceeds the threshold (Yes in step 304), the discharge control unit 54 checks the discharge history recorded in the discharge history data 50 and determines whether dummy discharge has already been performed. To do. When it is determined that the dummy discharge is not performed (No in Step 305), the temperature selection unit 52 selects the optimum temperature to be heated by the heater 61, and the heater 61 heats the head 27 at the selected temperature ( Step 306), the heater 60 and the heater 61 are both heated.

  In this state, when the ejection controller 54 instructs the head unit 10 to eject the liquid material, the liquid material is dummy ejected from the head 27 to the dummy region D of the substrate S as shown in FIG. Step 307). When the liquid material inside the head 27 is discharged, the heating by the heater 61 is terminated and the head 27 is cooled (step 308). If it is determined in step 304 that the elapsed time is less than the threshold (No in step 304), step 304 is repeatedly performed.

  If it is determined in step 305 that dummy discharge has already been performed (Yes in step 305), the heater 60 is heated and the heater 61 is not heated, as shown in FIG. For example, the liquid material is actually discharged onto the display area A of S (step 309).

Thus, according to the present embodiment, the liquid material is heated via the tube 12 by the heater 60. Since the liquid material is heated by the heater 60, the liquid material can be returned to the original viscosity of the liquid material (a state before the thickening starts) before discharging from the head 27, so that stable discharge is performed. Will be able to.
At this time, if the flow rate of the liquid material is large, the effective time for heating is short, and if the flow rate is small, the effective time for heating becomes long. If the effective heating time is shortened, the heat treatment becomes insufficient and the liquid material cannot be returned to its original viscosity. On the other hand, when the effective heating time is long, the heat treatment becomes excessive, which may cause deterioration of the liquid material. For this reason, by controlling the heating temperature of the heater 60 based on the data regarding the flow velocity of the liquid material flowing through the tube 12, it is possible to supply a liquid material having a stable viscosity and no deterioration to the ejection head.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, it has been described that the flow velocity data is formed based on the discharge amount of the liquid material. However, the present invention is not limited to this, and for example, the flow velocity data is actually measured using a flow meter, and the measured value is obtained as flow velocity data. It does not matter.

It is a perspective view which shows the structure of the droplet discharge apparatus which concerns on embodiment of this invention. It is a disassembled perspective view which shows the structure of the head of the droplet discharge apparatus which concerns on this embodiment. It is a block diagram which shows the structure of the control part of the droplet discharge apparatus which concerns on this embodiment. It is a graph which shows the time-dependent change of the viscosity of a liquid material. It is a flowchart which shows operation | movement of the droplet discharge apparatus which concerns on this embodiment. It is FIG. (1) which shows the mode of operation | movement of the droplet discharge apparatus which concerns on this embodiment. It is FIG. (2) which shows the mode of operation | movement of the droplet discharge apparatus which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Droplet discharge device 5 ... Control part 10 ... Head unit 12 ... Tube 32 ... Timer 44 ... Data storage part 45 ... Program storage part 46 ... Flow rate data 47 ... Distance data 48 ... Temperature data 49 ... Time data 50 ... Discharge history Data 51 ... Arrival time calculation unit 52 ... Temperature selection unit 53 ... Elapsed time determination unit 54 ... Discharge control unit 60, 61 ... Heater

Claims (4)

A head for holding the liquid material and discharging the held liquid material;
Supply means having a flow path for supplying the liquid material to the head;
A flow path heating unit provided in the flow path at a predetermined distance from the head and capable of heating the flow path;
And a controller that controls a heating temperature of the flow path heating unit based on data relating to a flow rate of the liquid material flowing through the flow path. A storage unit for storing data relating to the flow velocity;
The control unit controls ejection of the liquid material, calculates an elapsed time until the liquid material passes through the flow path heating unit using the predetermined distance and the flow velocity, and calculates the calculated The droplet discharge device according to claim 1, wherein the heating temperature of the flow path heating unit is controlled according to the length of elapsed time. A head heating unit capable of heating the head;
When the controller discharges the liquid material as a dummy, the flow path and the head are heated. When the liquid material is discharged, the flow path is heated and the head is not heated. The droplet discharge device according to claim 1, wherein a path heating unit and the head heating unit are controlled. The storage unit further stores data relating to the time required for the liquid material to be heated by the flow path heating unit to return to the original viscosity in the flow path after the viscosity is reduced,
The control unit is
Determining whether the elapsed time since the liquid material began to be heated exceeds the required time and determining whether the liquid material has already been dummy ejected;
When it is determined that the elapsed time exceeds the required time and the liquid material is not discharged by dummy, the flow path heating unit and the head heating unit are heated so that the flow path and the head are heated. And controlling the head so that the liquid material is dummy discharged,
When the elapsed time exceeds the required time and it is determined that the liquid material has already been dummy ejected, the flow path heating unit and the head heating unit are configured so that the flow path is heated and the head is not heated. The droplet discharge device according to claim 2, wherein the head is controlled so that the liquid material is actually discharged.

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