JP5903653B2 - Liquid ejection method and liquid ejection apparatus - Google Patents

Description

  The present invention relates to a liquid ejection method and a liquid ejection apparatus for ejecting liquid in the form of droplets, and in particular, can be applied to a liquid containing a solid in a dispersed state or a liquid with high viscosity, and the ejection amount is accurately controlled. The present invention relates to a liquid discharge method and a liquid discharge apparatus.

  Conventionally, as one of printing techniques, there is an ink jet technique in which an ink liquid is ejected at an accurate position to print an image on a paper surface. In recent years, the ink-jet technology has been applied to pattern formation and uniform thin film formation in various device manufacturing processes.

  Furthermore, in order for the ink jet technology to be widely applied to fields other than printing of characters and graphics, a liquid ejecting apparatus capable of ejecting various types of liquid is required. For example, in order to emit white light using a blue light emitting diode as a light source, it is necessary to form a transparent resin layer containing fine solid phosphors in a dispersed state on the surface of the light emitting diode. A liquid discharge device for discharging the contained liquid is required. Further, in the process of manufacturing a semiconductor device, it is necessary to discharge a thermosetting resin having a high viscosity, and a liquid discharging apparatus that discharges a high-viscosity liquid in an accurate amount is required.

  As one of apparatuses capable of discharging such various types of liquids, for example, the invention described in Patent Document 1 can be exemplified. The liquid discharge apparatus described in Patent Document 1 is a storage chamber that can change its volume, and is a storage chamber in which a supply hole for supplying a liquid and a discharge hole for discharging a liquid are provided in communication with each other. The liquid to be discharged is stored in the chamber, and the volume of the storage chamber is reduced in a short time to discharge the liquid from the discharge hole.

  However, the liquid discharge device having the above-described structure can accurately discharge a certain amount of liquid by filling the liquid to the limit of the opening of the discharge hole. However, the liquid discharge device fills the discharge hole with the surface tension of the liquid. There is a problem that the time until the whole hole is filled with the liquid becomes long. In addition, if the internal volume of the discharge hole is increased in order to discharge a large amount of liquid, the time until the liquid is filled in the discharge hole becomes longer, so it is difficult to discharge a large amount of liquid within a certain time. Met.

  On the other hand, when the liquid is forcibly supplied by applying pressure to the liquid in order to accelerate the filling of the liquid, the liquid is supplied in the liquid discharge device having a structure from the supply hole to the discharge hole through the storage chamber. There is a risk of liquid leaking from the discharge hole due to the pressure of the liquid, and it has been difficult to obtain high discharge efficiency in a stable state.

  Therefore, even when the pressure of the liquid supplied to the storage chamber or discharge hole is increased, by stopping the pressure applied to the liquid under appropriate conditions, it is possible to reduce the adverse effect on the accuracy of the discharge amount and fill the liquid at high speed. The applicant of the present application has separately filed a liquid ejection apparatus and a liquid ejection method that do not cause problems such as liquid leakage.

JP 2008-307466 A

  However, as a result of the inventor's diligent experiment and research on the liquid ejecting apparatus, when the liquid droplets are ejected to one place continuously several times, and the liquid is ejected to several other places, the liquid is ejected. As a result, liquid leakage occurred on the nozzle surface, and a slight variation was found in the total amount of droplets at each location.

  As a result of further experimentation and research, it has been found that a transient phenomenon when pressure is applied to the liquid to be supplied affects the variation.

  The present invention has been made based on the above knowledge, and can discharge liquid at high speed so that the total amount of droplets continuously discharged at one place becomes a desired amount. It is an object of the present invention to provide a liquid ejection method and a liquid ejection apparatus in which the total amount of droplets is uniform.

  In order to achieve the above object, a liquid ejection method according to the present invention is a liquid ejection apparatus including ejection means for ejecting liquid as droplets, and the ejection means is at least partially formed of an elastic member. Increase and decrease the volume of the storage chamber, an elastic discharge body that communicates with the storage chamber, forms a supply hole that supplies liquid into the storage chamber, and a discharge hole that discharges liquid in the storage chamber. Actuating means, pressurizing means for applying pressure to the liquid so that the pressure of the liquid supplied to the storage chamber is greater than atmospheric pressure, and controlling whether or not to supply the pressurized liquid to the storage chamber A liquid discharge method for discharging a liquid from a liquid discharge apparatus comprising a supply control means for controlling and an operation control section for controlling the operation of the operation means, wherein the operation control section is n times (n is a natural number of 3 or more) Operate the actuating means intermittently If the operation of discharging n liquids is defined as a discharge operation group, the first timing which is the first liquid discharge timing in the discharge operation group and the timing at which the supply control means starts supplying the liquid. An interval between a first timing that is a first liquid discharge timing and a second timing that is a liquid discharge timing subsequent to the first timing in the discharge operation group is related to a certain start timing, and the second timing. And the operation control unit controls the operation means so as to be longer than an interval between the second timing and the third timing that is the liquid discharge timing next to the second timing.

  Accordingly, it is possible to stably discharge a desired amount of liquid in the initial stage of the discharge operation group, and it is possible to accurately estimate the total discharge amount of liquid in the discharge operation group.

  Further, a value obtained by time-integrating a change in pressure of the liquid supplied to the storage chamber from the first timing to the second timing, and a value obtained by time-integrating the change in pressure from the second timing to the third timing. The operation control unit may control the operation means so that the two coincide with each other.

  According to this, it is possible to simply stabilize each discharge amount of the discharge operation group without measuring the liquid discharge amount at each timing.

  Further, the supply control means supplies the liquid so that the end timing, which is the timing at which the supply control means ends the supply of the liquid, is earlier than the nth timing, which is the last liquid discharge timing in the discharge operation group. The interval between the n-th timing and the (n-1) th timing which is the liquid ejection timing immediately before the n-th timing in the ejection operation group is the n-1th timing and the n-1th timing. The operation control unit may control the operation means so as to be longer than an interval from the (n-2) th timing that is the liquid discharge timing immediately before the timing.

  According to this, even when the end timing is earlier than the nth timing in the relationship of the next discharge operation group, it is possible to stably discharge a desired amount of liquid until the end of the discharge operation group. It becomes.

  Further, the operation control unit may sequentially acquire the pressure value and integrate the time to control the operation means.

  According to this, it becomes possible to adjust the discharge timing and stabilize the liquid discharge amount in real time. Therefore, even when the liquid state (for example, viscosity) changes due to a change in the installation environment (for example, temperature) of the liquid discharge device, it is possible to maintain a stable discharge amount.

  In order to achieve the above object, a liquid ejection apparatus according to the present invention is a liquid ejection apparatus including ejection means for ejecting liquid as droplets, and the ejection means is at least partially formed by an elastic member. A storage chamber, a supply hole that communicates with the storage chamber and supplies a liquid into the storage chamber, an elastic discharge body that discharges the liquid in the storage chamber, and a volume of the storage chamber. An operating means for increasing or decreasing the pressure, and the liquid ejection device further includes a pressurizing means for applying pressure to the liquid so that a pressure of the liquid supplied to the storage chamber is greater than an atmospheric pressure, and pressurizing the storage chamber Supply control means for controlling whether or not the supplied liquid is supplied, an operation control section for controlling the operation of the operation means, and the operation control section is intermittently operated n times (n is a natural number of 3 or more). Discharge n liquids by operating the means When the operation to be performed is defined as a discharge operation group, the first timing that is the first liquid discharge timing in the discharge operation group and the start timing that is the timing at which the supply control unit starts the supply of liquid The related unit and the operation control unit have an interval between a first timing that is a first liquid discharge timing and a second timing that is a liquid discharge timing next to the first timing in the discharge operation group. An interval adjusting unit is provided for controlling the operating means so as to be longer than an interval between a second timing and a third timing that is a liquid discharge timing next to the second timing.

  Accordingly, it is possible to stably discharge a desired amount of liquid in the initial stage of the discharge operation group, and it is possible to accurately estimate the total discharge amount of liquid in the discharge operation group.

  Furthermore, you may provide the detection means which detects the pressure applied by the said pressurization means.

  According to this, it is possible to adjust the discharge timing and stabilize the liquid discharge amount by measuring the pressure in real time by the detection means. Therefore, even when the liquid state (for example, viscosity) changes due to a change in the installation environment (for example, temperature) of the liquid discharge device, it is possible to maintain a stable discharge amount.

  Note that executing a program for causing a computer to execute each process included in the liquid ejection method also corresponds to the implementation of the present invention. Of course, implementing the recording medium in which the program is recorded also corresponds to the implementation of the present invention.

  According to the present invention, even when liquid is supplied while being pressurized and the liquid is intermittently discharged as droplets a plurality of times, the discharge amount of the liquid can be stabilized from the start to the end of pressurization.

FIG. 1 is a perspective view showing a schematic configuration of the liquid ejection apparatus. FIG. 2 is a perspective view showing a schematic configuration of a part related to liquid ejection of the liquid ejection apparatus in an exploded state. FIG. 3 is a perspective view schematically showing an appearance of a portion related to liquid discharge of the liquid discharge apparatus. FIG. 4 is a partial cross-sectional view illustrating a schematic configuration of a portion related to liquid discharge of the liquid discharge apparatus. FIG. 5 is a block diagram illustrating a functional configuration of a portion related to liquid discharge of the liquid discharge apparatus. 6A and 6B are diagrams schematically showing a cross section of the discharge means in the liquid discharge operation. FIG. 6A shows a state immediately before discharge, and FIG. 6B shows a state immediately after discharge. FIG. 7 is a diagram illustrating the control timing of the operation control unit and the supply control unit, and the state of the liquid pressure. FIG. 8 is a diagram illustrating another example of the control timing of the operation control unit and the supply control unit, and the state of the pressure of the liquid.

  Next, embodiments of a liquid ejection method and a liquid ejection apparatus according to the present invention will be described with reference to the drawings. The following embodiments are merely examples of the liquid ejection apparatus and the liquid ejection method according to the present invention. Accordingly, the scope of the present invention is defined by the wording of the claims with reference to the following embodiments, and is not limited to the following embodiments.

  FIG. 1 is a perspective view showing a schematic configuration of the liquid ejection apparatus.

  The liquid discharge apparatus 100 according to this embodiment can continuously execute discharging a plurality of liquids 201 to a desired position on the object 204 and discharging a plurality of liquids 201 to different positions. This is an apparatus that can include a head 221 and a stage 231 that supports the workpiece 204.

  The head 221 is provided with one or a plurality of ejection means 101 (described later), and reciprocates in the main scanning direction (X-axis direction shown in FIG. 1) by the head moving device 202 supported by the apparatus base 206. The stage 231 reciprocates in the sub-scanning direction (Y-axis direction shown in FIG. 1) by the stage moving device 203 that is also supported on the apparatus base 206.

  With this configuration, the liquid discharge apparatus 100 intermittently discharges the liquid 201 from the discharge unit 101 provided in the head 221 toward the target object 204 while relatively moving the head 221 and the target object 204 on the stage 231. A pattern, a film, or the like formed by a plurality of droplets is formed at a plurality of locations on the substrate 204.

  FIG. 2 is a perspective view showing a schematic configuration of a part related to liquid ejection of the liquid ejection apparatus in an exploded state.

  FIG. 3 is a perspective view schematically showing an appearance of a portion related to liquid discharge of the liquid discharge apparatus.

  FIG. 4 is a partial cross-sectional view illustrating a schematic configuration of a portion related to liquid discharge of the liquid discharge apparatus.

  FIG. 5 is a block diagram illustrating a functional configuration of a portion related to liquid discharge of the liquid discharge apparatus.

  As shown in these drawings, the liquid ejecting apparatus 100 is an apparatus capable of intermittently ejecting a desired liquid 201 as a droplet by a predetermined amount, and includes an ejecting unit 101, a pressurizing unit 102, A supply control unit 103, an operation control unit 104, a supply source 210, and a related unit 191 are provided.

  The discharge means 101 includes an elastic discharge body 105 and an operation means 114, and the volume of the storage chamber 110 is reduced in a short time with the liquid 201 filled in the storage chamber 110 formed inside the elastic discharge body 105. Can be discharged as droplets. In the case of the present embodiment, the elastic discharge body 105 is formed by the first member 111, the second member 112, and the elastic member 113.

  The first member 111 is a member that is a part of the elastic discharge body 105 and forms a part of the storage chamber 110. The first member 111 is a tubular body that also functions as the supply path 115 for the liquid 201, and the tip portion has a conical shape whose area gradually increases toward the tip surface (on the Z axis, the second member 112 side). A (tapered) recess is formed. The recess corresponds to a part (one member) of the storage chamber 110. Further, an orifice-shaped supply hole 116 that allows the supply path 115 and the storage chamber 110 to communicate with each other is provided at a portion corresponding to the apex of the conical recess. The first member 111 is a member that compresses the elastic member 113 with the second member 112.

  The second member 112 is a member that forms another part (the other member) of the storage chamber 110 and is provided with a discharge hole 117 that discharges the liquid 201 in the storage chamber 110. In the case of the present embodiment, the second member 112 includes a tapered recess that gradually increases in area from the discharge hole 117 toward the first member 111, and the recess of the first member 111 and the second member 112. The storage chamber 110 is formed by disposing the recesses facing each other. The second member 112 is a member that opposes the first member 111 and compresses the elastic member 113.

  The elastic member 113 is a member that is disposed between the first member 111 and the second member 112 and changes the volume of the storage chamber 110. In the case of the present embodiment, the elastic member 113 has a thin plate-like annular shape, and the portion sandwiched between the two recesses (between the first member 111 and the second member 112) is the two recesses. A hole having a corresponding shape is provided in a penetrating state in the thickness direction (Z-axis direction) so as to communicate with each other. Specifically, the elastic member 113 is a combination of the first member 111 and the second member 112 constituting the storage chamber 110 and the flexibility that can reduce the distance between the first member 111 and the second member 112 by the operating means 114. It is a member having sealing properties that can prevent liquid leakage of the surface, strength that can resist the pressure of the liquid 201 in the storage chamber 110, and resilience that can discharge the liquid 201 multiple times. For example, it is formed of a member having elasticity and chemical resistance such as fluoro rubber and silicon rubber.

  The orifice-like supply hole 116 and the discharge hole 117 for supplying the liquid 201 are arranged on a straight line (coaxially) so as to reduce the resistance to the liquid 201, but are not limited to this. The tube axis of the supply hole 116 and the tube axis of the discharge hole 117 may be separated from each other.

  In a normal state (normal time in which the liquid 201 can be supplied to the storage chamber 110), the operation unit 114 extends the storage chamber 110 in the Z-axis direction to increase the volume (see FIG. 6A). Actuator for generating a force that compresses the elastic member 113 and reduces the volume of the storage chamber 110 by relatively reducing the distance between the first member 111 and the second member 112 when discharging the gas (see FIG. 6B). It is. The actuating means 114 may be one that activates the first member 111 and the second member by air pressure or one that actuates electromagnetically, but a piezoelectric element is preferable in consideration of the size and response speed of the device. It is. In particular, the actuating means 114 is preferably a laminated piezoelectric material.

  In the case of the present embodiment, the actuating means 114 generates a force in a direction (Z-axis direction) in which the distance between the first member 111 and the second member 112 extends by supplying a voltage. One end (upper end) in the expansion / contraction direction (Z-axis direction) is fixedly and firmly connected to the outer peripheral surface of the first member 111 with an adhesive or the like, and the other end (lower end) is connected to a part of the second member 112. It is connected via an elastic member 113. In the case of this embodiment, the other end (lower end) of the actuating means 114 is connected to a part of a second member 112 held by a case 119 described later via an elastic member 113, and an adhesive. It is not something that is fixedly connected.

  Specifically, the actuating means 114 extends the length in the Z-axis direction by applying a voltage to the electrode 118, as shown in FIG. 6 (b), the storage chamber 110 filled with the liquid 201 with the first member 111 and the elastic member 113 constituting a part of the storage chamber 110 are compressed by being contracted in the Z-axis direction. The volume of the storage chamber 110 can be changed and the liquid 201 can be discharged.

  In the case of the present embodiment, the ejection unit 101 further includes a housing 119 and an urging unit 120.

  The housing 119 is disposed at a position where the elastic member 113 is sandwiched between the first member 111 fixedly connected to the operating unit 114 and the operating unit 114 and the second member 112, and is configured to be disassembled. Has been.

  The urging unit 120 includes an urging force in a direction in which the actuating unit 114 is pressed against the second member 112 via the housing 119. In the case of the present embodiment, the biasing means 120 is a disc spring.

  The supply source 210 holds the liquid 201 supplied to the storage chamber 110, and includes a syringe 211, a plunger 212, and detection means 219 in the case of the present embodiment.

  The syringe 211 is a cylindrical container that can hold the liquid 201 inward and supply the liquid 201 to the storage chamber 110 at a constant pressure by moving the plunger 212, and the holding chamber that holds the liquid 201. 213 and a sealed pressure adjusting chamber 214 on the opposite side of the holding chamber 213 with respect to the plunger 212.

  The plunger 212 is a piston that is slidably disposed inside the syringe 211 with respect to the syringe 211 and can push out the liquid 201 in the syringe 211.

  The supply source 210 of the above aspect is preferable because no pulsation occurs compared to a pump structure that supplies the liquid 201.

  The pressurizing means 102 is a device that applies pressure to the liquid 201 so that the pressure of the liquid 201 supplied to the storage chamber 110 is greater than atmospheric pressure. In the case of the present embodiment, since the supply source 210 is constituted by the syringe 211 and the plunger 212, the pressurizing means 102 introduces pressurized air into the pressure adjustment chamber 214 of the supply source 210. It is a device that can. In the present embodiment, the supply source 210 is at a higher position than the ejection unit 101, but the supply source 210 may be disposed at a lower position. Thereby, it is possible to easily supply the liquid 201 to the discharge means 101 at a pressure higher than the atmospheric pressure. As described above, the pressurizing unit 102 pressurizes the liquid 201 by introducing the pressurized air into the pressure adjusting chamber 214 to slide the plunger 212 relative to the syringe 211.

  Note that the pressurizing means 102 is not limited to a device such as an air compressor that generates pressurized air, but may be a device that mechanically moves the plunger 212 relative to the syringe 211.

  The detecting unit 219 is a sensor that detects the pressure applied by the pressurizing unit 102. In the case of the present embodiment, the detection means 219 is arranged between the first valve 131 and the syringe 211 and detects the air pressure in the pressure adjustment chamber 214 of the syringe 211. Although the detection means 219 is not particularly limited, for example, a sensor that reads the displacement of the diaphragm with a load cell can be listed.

  Note that the detection unit 219 may detect the pressure of the liquid 201 in the holding chamber 213 or the supply path 115. Further, the mechanical output (for example, torque) of the pressurizing means 102, the input power amount, and the like may be measured and the value may be handled as pressure.

  The supply control means 103 is a device that controls whether or not the pressurized liquid 201 is supplied to the storage chamber 110. In the case of the present embodiment, the supply control means 103 includes a first valve 131 and a supply control unit 132 (see FIGS. 4 and 5).

  The first valve 131 is a valve body provided in an air path that connects the pressurizing means 102 (air compressor, factory air source, etc.) and the pressure adjustment chamber 214, and is pressure air introduced into the pressure adjustment chamber 214? Whether or not can be controlled by opening and closing the valve.

  In the case of the present embodiment, the first valve 131 is a three-port valve (see FIG. 4). That is, when the first valve 131 is closed, the pressurized air supplied from the pressurizing means 102 to the pressure adjusting chamber 214 is shut off, and the pressure adjusting chamber 214 is switched to communicate with another path. . The other path is open to atmospheric pressure.

  In the case of the present embodiment, the supply control means 103 controls the pressurizing means 102 to supply the liquid 201 to the storage chamber 110 by applying pressure to the liquid 201 and to stop the pressurization to supply the liquid 201. Has stopped. Further, by disposing the supply source 210 at a position lower than the ejection unit 101, the liquid 201 can be efficiently supplied and stopped at an atmospheric pressure or higher.

  The supply control unit 132 is a processing unit realized by the main control device 109 such as a computer provided in the liquid ejection device 100, and is a processing unit that controls opening and closing of the first valve 131.

  When the pressurizing unit 102 is a pump or the like, the supply control unit 103 does not control the supply of the liquid 201 by opening and closing the valve, but controls the operation and non-operation of the pump to supply the liquid 201. It is possible to control.

  The operation control unit 104 is a processing unit that controls the operation of the operation unit 114. In this embodiment, since the actuating means 114 is constituted by a piezoelectric element, the operation of the actuating means 114 is controlled by controlling whether or not a voltage is applied to the two electrodes 118 provided in the actuating means 114. Is controlling. The operation control unit 104 may control the operation of the operation unit 114 by changing a voltage applied to the operation unit 114.

  Further, the operation control unit 104 includes an interval adjustment unit 141. The interval adjusting unit 141 is a processing unit that adjusts the interval at which the operation control unit 104 operates the operating unit 114. The interval adjusting unit 141 may operate the operating unit 114 at an interval based on a preset value (an experimental value or a value obtained from a theoretical value in advance), and based on the value from the detecting unit 219. The operation timing of the operating means 114 may be adjusted in real time.

  The related unit 191 is a processing unit that adjusts the timing at which the liquid 201 is ejected from the ejection hole 117 of the elastic ejection body 105 and the timing at which the pressurized liquid 201 is supplied to the storage chamber 110. Timing is adjusted by exchanging information with the supply control unit 132. Specifically, the related unit 191 includes a start related unit 192 and an end related unit 193.

  The start related unit 192 is a processing unit that associates the first liquid discharge timing in the discharge operation group, which is a series of operations for intermittently discharging the liquid 201, with the timing at which the supply control unit 132 starts supplying the liquid. is there.

The termination related unit 193 is a processing unit that associates the last liquid ejection timing in the ejection operation group with the timing at which the supply control unit 132 terminates the liquid supply. Next, the operation of the liquid ejection apparatus 100 configured as described above. Will be described.

  FIG. 7 is a diagram illustrating the control timing of the operation control unit and the supply control unit, and the state of the liquid pressure.

  As shown in the figure, the operation control unit 104 intermittently operates the operation unit 114 n times (n is a natural number of 3 or more) to discharge n liquid droplets (liquid 201). In the present embodiment, a series of operation groups of the actuating means 114 is defined as a discharge operation group. The discharge operation group operates a plurality of actuation means 114 from the start to the end of applying pressure to the liquid 201, that is, a set of a plurality of discharge operations.

  The start related unit 192 associates the first timing 1 that is the first liquid discharge timing in the discharge operation group with the start timing that is the timing at which the supply control unit 132 of the supply control unit 103 starts supplying the liquid 201. ing. In the case of the present embodiment, the first timing 1 and the start timing are synchronized.

  A specific example of the discharge operation of the liquid 201 will be described in detail.

  First, the operation control unit 104 applies a predetermined voltage (for example, 20 V) to the operation unit 114 in advance, thereby extending the operation unit 114 in the Z-axis direction and increasing the volume of the storage chamber 110 (FIG. 6A ) State).

  Next, through the supply hole 116 in which the flow path diameter is once narrowed in the storage chamber 110 having a large volume and immediately before entering the storage chamber 110, which is the supply inlet of the liquid 201, into the discharge hole 117. Fill with liquid 201. Filling of the liquid 201 is performed when the supply control unit 132 operates the first valve 131 to apply pressure to the liquid 201 in the syringe 211.

  The start related unit 192 synchronizes the operation control unit 104 with the operation of the first valve 131 by the supply control unit 132, and the operation control unit 104 sets the voltage applied to the operation unit 114 in advance for a very short time (for example, 10 μsec to 10 msec). )To release. As a result, the operating means 114 instantaneously contracts in the Z-axis direction (state shown in FIG. 6B).

  As described above, the liquid 201 is discharged from the discharge hole 117 having a lower back pressure resistance (discharge resistance on the discharge hole 117 side) than the supply hole 116 that is the supply port of the liquid 201 in the storage chamber 110, and the liquid 201 is directed toward the substrate 204. One drop is discharged as a drop. The droplets adhere to the upper surface of the coated body 204 in the form of dots.

  Here, in the discharge operation group m, the liquid chamber 201 and the discharge hole 117 are sufficiently filled with the liquid 201 and the meniscus generated in the discharge hole 117 is stable after the discharge operation group m-1 ends. Since the process is started in this state, the amount of the liquid 201 ejected at the first timing 1 is close to a desired amount.

  Next, the liquid 201 is discharged at the second timing 2 by the same operation as described above. Since the pressure of the liquid 201 filled in the storage chamber 110 and the discharge hole 117 (the air pressure in the pressure adjusting chamber 214 seems to be in a linear proportional relationship) is in a transient state, the first timing 1 The time T1 up to the second timing 2 will be in a state where the storage chamber 110 and the discharge hole 117 are sufficiently filled with the liquid 201 and the meniscus generated in the discharge hole 117 is also stable. The time T1 is set, and the interval adjusting unit 141 of the operation control unit 104 controls the operation unit 114 based on T1.

  Next, the liquid 201 is discharged at the third timing 3 by the same operation as described above. Although the pressure of the liquid 201 filled in the storage chamber 110 and the discharge hole 117 is still in a transient state, since it is almost the desired pressure, T2 which is the time from the second timing 2 to the third timing 3 is , T1 is set to a value shorter than T1, and the interval adjustment unit 141 of the operation control unit 104 controls the operation unit 114 based on T2.

  Next, the liquid 201 is discharged at the fourth timing 4 by the same operation as described above. Since the pressure of the liquid 201 filled in the storage chamber 110 and the discharge hole 117 has reached a desired pressure, T3, which is the time from the third timing 3 to the fourth timing 4, is shorter than T2. The interval adjustment unit 141 of the operation control unit 104 controls the operation unit 114 based on T3.

  Next, the discharge interval T4 to Tn-2 of the liquid 201 from the fifth timing (not shown) to the (n-1) th timing in a state where the pressure of the liquid 201 is stable is set to the same interval as T3. The interval adjusting unit 141 of the operation control unit 104 controls the operation unit 114 based on T4 to Tn-2.

  As described above, by adjusting the discharge intervals T1, T2 and the like to be gradually shorter as time elapses, it is possible to avoid problems that occur when the discharge intervals are made equal.

  Here, it is considered that the troubles caused when the discharge intervals are equal are caused by the following phenomenon. That is, assuming that the discharge interval is equal, the discharge amount of the liquid 201 at the second timing 2 is particularly smaller than the discharge amount at the first timing 1. When the discharge amount becomes smaller than the specified amount, the discharge speed of the liquid 201 becomes slow, and the liquid 201 remains in a wet state on the nozzle surface near the opening of the nozzle hole 117. Then, the liquid 201 remaining on the nozzle surface causes a malfunction (adverse effect) in the ejection of the liquid 201 at the third timing 3. Specific problems (discharge failures) can be listed as follows, for example, deterioration of straightness of discharged liquid 201 (droplet), decrease in flight speed of discharged liquid 201 (droplet), liquid For example, occurrence of splashes other than droplets.

  In the present embodiment, when the pressure of the liquid 201 rises slowly (see FIG. 7), for example, when the volume of the pressure adjustment chamber 214 of the syringe 211 is large (the amount of air is large), the discharge interval is set to T1. Although the embodiment of adjusting so that> T2> T3 has been described, when the pressure of the liquid 201 rises quickly (see FIG. 8), for example, the volume of the pressure adjustment chamber 214 of the syringe 211 is small (the amount of air is small). In this case, the discharge interval may be adjusted so that T1> T2 = T3.

  Here, the values of T1 to Tn-1 are obtained as follows.

  For example, the amount of the liquid 201 actually discharged from the first timing 1 to the nth timing n is measured in advance, and the intervals T1 to Tn-1 are adjusted so that the respective discharge amounts are stabilized, whereby T1 to T1. What is necessary is just to obtain | require the value of Tn-1.

  Further, the inventor of the present application has obtained the following knowledge in the course of the measurement. That is, as shown in the lowermost stage of FIG. 7, if the values obtained by time integration of the pressure values obtained by the detection means 219 at intervals of T1 to Tn-1 match, the discharge amount at each timing is also stabilized. Heading.

  Therefore, the values of T1 to Tn−1 are the detection means 219 when supplying the pressurized liquid 201 to the storage chamber 110 without stopping the discharge amount of the liquid 201 and when stopping the supply. It is also possible to obtain the measured pressure values by calculating the intervals T1 to Tn-1 so that the time integration of the change in pressure is the same.

  Then, the interval T1 to Tn-1 obtained by measurement or calculation may be acquired by the interval adjusting unit 141 of the operation control unit 104 to adjust the interval at which the operating unit 114 is operated.

  Furthermore, by acquiring the value of the detection means 219 in real time (sequentially) and performing sequential time integration, the interval adjusting unit 141 determines whether or not the integrated value from the first timing 1 exceeds the threshold value. If the threshold value is exceeded, the second actuating means 114 is judged to be operable at the second timing 2, and the judgment is sequentially repeated to determine the intervals T1 to Tn-1 in real time and to control the actuating means 114. It doesn't matter.

  As the last of the discharge operation group m, the end-related unit 193 causes the nth timing n, which is the discharge timing of the last liquid 201 in the discharge operation group, and the supply control unit 132 of the supply control unit 103 to end the supply of the liquid 201. The timing is related to the end timing.

  The present inventor has obtained the following knowledge. For example, when the volume of the pressure adjustment chamber 214 in the syringe 211 is relatively large, the pressure of the liquid 201 falls slowly (see FIG. 7). In such a state, when the end timing, which is the timing for ending the supply of the liquid 201, is delayed from the nth timing n, which is the discharge timing of the last liquid 201 in the discharge operation group m, for example, the liquid is also discharged after the last discharge. Since 201 is supplied, the supply amount of the liquid 201 becomes excessive, and the nozzle surface becomes wet. Accordingly, a malfunction (adverse effect due to the wet liquid 201) occurs when the first liquid 201 of the next ejection operation group m + 1 is ejected. In addition, a long time is required until the wet state of the nozzle surface is resolved and the meniscus is stabilized.

  Therefore, in the case of the present embodiment, the control is performed in association with the end timing, which is the timing for ending the supply of the liquid 201, slightly earlier than the nth timing n, which is the discharge timing of the last liquid 201.

  Thereby, the time integration value I until the discharge operation group m ends and the next discharge operation group m + 1 starts can be made to coincide with the time integration values at Tn-2 and Tn-1. Problems that occur in the first ejection of the operation group m + 1 can be suppressed as much as possible.

  Further, since the end timing is controlled earlier than the nth timing n, Tn−1, which is the interval between the nth timing n and the n−1th timing n−1, is the n−1th timing n. The interval adjusting unit 141 of the operation control unit 104 controls the operating unit 114 so as to be longer than Tn-2, which is the interval between -1 and the (n-2) th timing n-2.

  Accordingly, the shortage of the supply amount of the liquid 201 due to the end timing being advanced from the nth timing n is compensated, and the discharge amount of the liquid 201 is stabilized.

  Thus, the discharge operation group m ends. In the discharge operation group m, the discharge amount of all the liquids 201 from the first timing 1 to the nth timing n is a desired amount and can be stabilized by adjusting the intervals T1 to Tn-1. . Accordingly, the total discharge amount discharged by the discharge operation group m is n times the desired discharge amount. Further, by performing the discharge operation group m-1 and the discharge operation group m + 1 under the same conditions, the total discharge amount between the discharge operation groups can be stabilized.

  On the other hand, for example, when the volume of the pressure adjustment chamber 214 in the syringe 211 is relatively small, the pressure of the liquid 201 falls quickly (see FIG. 8). In such a state, when the end timing, which is the timing to end the supply of the liquid 201, is made earlier than the nth timing n, which is the discharge timing of the last liquid 201 in the discharge operation group m, for example, the supply amount of the liquid 201 is It will be insufficient.

  Therefore, the control is performed in association with the end timing, which is the timing for ending the supply of the liquid 201, slightly later than the nth timing n, which is the discharge timing of the last liquid 201.

  The time from the n-th timing n to the end timing is the time integration value I at the time Tn−1 when the discharge operation group m ends and the next discharge operation group m + 1 starts. Adjust to match.

In addition, this invention is not limited to the said embodiment. For example, another embodiment realized by arbitrarily combining the components described in this specification and excluding some of the components may be used as an embodiment of the present invention. In addition, the present invention includes modifications obtained by making various modifications conceivable by those skilled in the art without departing from the gist of the present invention, that is, the meaning described in the claims. It is.

  For example, when the liquid 201 is not supplied to the storage chamber 110, the embodiment has been described assuming that the pressure adjustment chamber 214 is opened to the atmosphere. However, the present invention is not limited to this, and for example, the liquid 201 is not supplied. In this case, the pressure adjusting chamber 214 may be a negative pressure lower than the atmospheric pressure.

  If the time integral value of the pressure until the discharge operation group m ends and the next discharge operation group m + 1 starts does not coincide with the value of the time integral at Tn−1 and is insufficient, in the discharge operation group m + 1. In association with the start timing of supply of the liquid 201 earlier than the first timing 1 of the discharge operation group m + 1, the value of the time integration at Tn−1 and the discharge operation group m are finished, and the next discharge operation group You may make it correspond with the sum of the value of the time integral of the pressure until m + 1 starts.

  Since the present invention can discharge a precise amount of liquid droplets at high speed regardless of the type of liquid, for example, for the production of various devices such as liquid crystal panels, circuit boards, and LED elements, It can be applied to a process for forming a uniform thin film. Further, it can be applied to a process of forming a film that emits white light from a monochromatic light emitter by discharging a liquid in which a solid phosphor is dispersed in a phosphor coating process such as an LED element.

DESCRIPTION OF SYMBOLS 100 Liquid discharge apparatus 101 Discharge means 102 Pressurization means 103 Supply control means 104 Operation control part 105 Elastic discharge body 109 Main control apparatus 110 Storage chamber 111 First member 112 Second member 113 Elastic member 114 Operation means 115 Supply path 116 Supply hole 117 Discharge hole 118 Electrode 119 Case 120 Energizing means 131 First valve 132 Supply control unit 141 Interval adjustment unit 191 Related unit 192 Start related unit 193 End related unit 201 Liquid 202 Head moving device 203 Stage moving device 204 Coating object 206 Device base 210 Supply source 211 Syringe 212 Plunger 213 Holding chamber 214 Pressure adjustment chamber 219 Detection means 221 Head 231 Stage

Claims (8)

An elastic discharger that forms a storage chamber that is at least partially formed of an elastic member, a supply hole that communicates with the storage chamber and that supplies liquid to the storage chamber, and a discharge hole that discharges the liquid in the storage chamber Operating means for increasing or decreasing the volume of the storage chamber, pressurizing means for applying pressure to the liquid so that the pressure of the liquid supplied to the storage chamber is greater than atmospheric pressure, and pressurizing the storage chamber A liquid ejection method for ejecting liquid from a liquid ejection device comprising: a supply control means for controlling whether or not to supply the liquid; and an operation control unit for controlling the operation of the operation means,
When the supply source for supplying the liquid to the storage chamber is lower than the storage chamber, or when the liquid is not discharged, the pressure applied to the liquid is stopped, or the pressure adjustment chamber provided in the supply source is set to atmospheric pressure. Lower negative pressure,
When the operation control unit defines the operation of intermittently operating the operation means n times (n is a natural number of 3 or more) and discharging n liquids as a discharge operation group,
The first timing that is the first liquid discharge timing in the discharge operation group is related to the start timing that is the timing at which the supply control unit starts the liquid supply,
The interval between the first timing that is the first liquid discharge timing and the second timing that is the liquid discharge timing next to the first timing in the discharge operation group is the second timing and the second timing next to the second timing. The liquid discharge method, wherein the operation control unit controls the operation means so as to be longer than an interval with a third timing that is a liquid discharge timing.   A value obtained by time-integrating the change in pressure of the liquid supplied to the storage chamber from the first timing to the second timing, and a value obtained by time-integrating the change in pressure from the second timing to the third timing. The liquid ejection method according to claim 1, wherein the operation control unit controls the operation unit so as to match. The supply control unit controls the supply of the liquid so that the end timing, which is the timing at which the supply control unit ends the supply of the liquid, is earlier than the nth timing, which is the final liquid discharge timing in the discharge operation group. And
The interval between the nth timing and the (n-1) th timing which is the liquid ejection timing immediately before the nth timing in the ejection operation group is one of the (n-1) th timing and the (n-1) th timing. The liquid ejection method according to claim 1, wherein the operation control unit controls the operation unit so as to be longer than an interval from an n−2th timing that is a previous liquid ejection timing.   A value obtained by time-integrating a change in pressure of the liquid supplied to the storage chamber from the (n-2) th timing to the (n-1) th timing, and a change in the pressure from the (n-1) th timing to the nth timing. The liquid ejection method according to claim 3, wherein the operation control unit controls the operation unit so that a value obtained by time integration matches.   The liquid ejection method according to claim 2, wherein the operation control unit sequentially acquires the pressure value, integrates the time, and controls the operation unit. A liquid ejection apparatus comprising ejection means for ejecting liquid as droplets,
The discharge means is
An elastic discharger that forms a storage chamber that is at least partially formed of an elastic member, a supply hole that communicates with the storage chamber and that supplies liquid to the storage chamber, and a discharge hole that discharges the liquid in the storage chamber When,
An operating means for increasing or decreasing the volume of the storage chamber ;
When the liquid is not disposed or is not ejected from the storage chamber, the pressure applied to the liquid is stopped, or the liquid is supplied to the storage chamber having a pressure adjustment chamber that makes the negative pressure lower than the atmospheric pressure. With a source ,
The liquid ejection device further includes
Pressurizing means for applying pressure to the liquid such that the pressure of the liquid supplied to the storage chamber is greater than atmospheric pressure;
Supply control means for controlling whether to supply pressurized liquid to the storage chamber;
An operation control unit for controlling the operation of the operation means;
When the operation control unit defines the operation of intermittently operating the operation means n times (n is a natural number of 3 or more) and discharging n liquids as a discharge operation group,
A start-related unit that associates a first timing that is a first liquid discharge timing in the discharge operation group with a start timing that is a timing at which the supply control unit starts supplying liquid;
The operation control unit is configured such that an interval between a first timing that is a first liquid discharge timing in the discharge operation group and a second timing that is a liquid discharge timing subsequent to the first timing is the second timing and the A liquid ejection apparatus comprising: an interval adjusting unit that controls the operating means so as to be longer than an interval with a third timing that is a liquid ejection timing next to a second timing. further,
The liquid ejecting apparatus according to claim 6, further comprising a detecting unit that detects a pressure applied by the pressurizing unit. further,
The end related part which relates the nth timing which is the last liquid discharge timing in the said discharge operation group, and the completion | finish timing which is the timing when the said supply control means complete | finishes supply of a liquid. Liquid ejection device.

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