JP2006218397A - Method for measuring the amount of liquid drops discharged, jig for measuring the amount of liquid drops discharged, method for adjusting the amount of liquid drops discharged, apparatus for measuring the amount of liquid drops discharged, and a drawing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for measuring the amount of liquid drops discharged, by which the amount of liquid drops discharged from a liquid drop discharge head of each nozzle can be measured, a jig for measuring the amount of liquid drops discharged, a method for adjusting the amount of liquid drops discharged, an apparatus for measuring the amount of liquid drops discharged, and a drawing apparatus. <P>SOLUTION: The present invention relates to a method for measuring the amount of liquid drops discharged, by which the amount of liquid drops discharged from a liquid drop discharge head 2 for discharging a liquid material in the form of liquid drops from a nozzle 25 is measured, which comprises a line-drawing step for drawing a line on an insulating liquid-drop-receiving part 31 for receiving liquid drops while relatively moving the liquid-drop-receiving part 31 and the liquid drop discharge head 2 and repeatedly discharging liquid drops from the nozzle 25 and an electrical resistivity-measuring step for measuring electrical resistivity of the line, whereby the amount of liquid drops discharged from the nozzle 25 for which the line is drawn is estimated from the measured electrical resistivity of the line. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a droplet discharge amount measuring method, a droplet discharge amount measuring jig, a droplet discharge amount adjusting method, a droplet discharge amount measuring apparatus, and a drawing apparatus.

As a method for forming a color element film (filter film, light emitting film, etc.) of a color filter substrate of a liquid crystal display device or a substrate with color elements such as an organic EL (Electro-Luminescence) display device, there is a method using an ink jet drawing apparatus. Are known. In this method, a liquid material for forming a color element film is applied to each of the color element regions (subpixels) surrounded by banks formed on the substrate by an ink jet drawing apparatus. That is, a liquid material is ejected as droplets by an ink jet drawing apparatus, and the droplets are landed on each color element region. The liquid material applied to each color element region is solidified or cured to form a color element film.
In this case, in order to accurately manage the film thickness of the color element film to be formed, it is necessary to accurately control the amount of liquid material applied to each color element region. It is necessary to know the amount per droplet discharged from the inkjet head.

Conventionally, as a method of measuring the droplet discharge amount of a droplet discharge head, droplets are discharged from all nozzles of the droplet discharge head, and the discharged droplets are received by a container and before and after receiving the droplets. The total weight of the droplets discharged into the receiving vessel is measured by measuring the weight of the receiving vessel, and the weight per droplet is measured by dividing this by the number of droplets (for example, Patent Document 1).
However, in the above droplet discharge amount measuring method, only the average value of all nozzles of the droplet discharge head is known. Actually, there is a variation in the discharge amount for each nozzle, and there is a problem that it is impossible to know the discharge amount of one drop for each nozzle.

  In simple terms, when a droplet is ejected to a receiving container, if the droplet is ejected from only one nozzle and the weight of the receiving container is measured before and after that, the amount of one droplet ejected from that nozzle can be determined. Although it seems that, even with the same nozzle, when one droplet is ejected from all nozzles, and when one droplet is ejected from only that nozzle, the amount of one droplet ejected is different. In this case, it is impossible to accurately know the discharge amount for each nozzle when discharging from all nozzles. Further, in this method, since the weights of the receiving containers must be measured for all the nozzles, there is a problem that the measurement takes a lot of time and labor.

JP 2004-177262 A

  An object of the present invention is to provide a droplet discharge amount measuring method, a droplet discharge amount measuring jig, and a droplet discharge amount adjusting method capable of measuring the amount of droplets discharged from a droplet discharge head for each nozzle. Another object is to provide a droplet discharge amount measuring device and a drawing device.

Such an object is achieved by the present invention described below.
The droplet discharge amount measuring method of the present invention is a droplet discharge amount measuring method for measuring a droplet discharge amount of a droplet discharge head that discharges a liquid material as droplets from a nozzle,
Line drawing for drawing a line on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the insulating droplet receiving portion that receives the droplet and the droplet discharge head Process,
An electrical resistance value measuring step for measuring an electrical resistance value of the line,
Based on the measured electric resistance value of the line, the droplet discharge amount of the nozzle on which the line is drawn is estimated.

Thereby, the amount of one droplet discharged from the droplet discharge head can be measured for each nozzle. That is, it is possible to accurately know the discharge amount per droplet as a measurement value of a specific nozzle, not as an average value of all nozzles.
In particular, it is possible to measure the discharge amount for each nozzle when droplets are discharged from all nozzles of the droplet discharge head. In general, even when the same nozzle is used, the discharge amount differs between when the droplets are discharged from all the nozzles and when the droplets are discharged only from the nozzles. When drawing on the workpiece, droplets are ejected from almost all nozzles of the droplet ejection head, so in the present invention, the droplet ejection amount of the nozzle in a state close to the actual drawing state is measured. Can be extremely useful.

In the droplet discharge amount measuring method of the present invention, it is preferable that the electric resistance value measuring step is performed in a state where the liquid material of the line is dried and solidified or cured.
Thereby, when the material contained in the liquid material has conductivity, the droplet discharge amount can be measured with higher accuracy.
In the droplet discharge amount measuring method of the present invention, it is preferable that the electric resistance value measuring step is performed in a state where the liquid material of the line is in a liquid state.
Thereby, even when the material contained in the liquid material is not conductive, the droplet discharge amount can be measured.

In the droplet discharge amount measuring method of the present invention, in the line drawing step, a plurality of lines are drawn on the droplet receiving portion by discharging droplets from a plurality of nozzles of the droplet discharge head,
In the electrical resistance value measuring step, the electrical resistance value of each of the plurality of lines is measured,
It is preferable to estimate the droplet discharge amount of each of the plurality of nozzles based on the measured electric resistance value of each line.
Thereby, the measurement about a some nozzle can be performed at once, and the time and labor which a measurement requires can be reduced significantly.

In the droplet discharge amount measuring method of the present invention, electrodes are provided at a plurality of locations on the droplet receiving portion,
In the line drawing step, a line is drawn so as to connect the two electrodes on the droplet receiving part,
In the electrical resistance value measuring step, it is preferable to measure an electrical resistance value between the two electrodes.
Thereby, the measurement of the electrical resistance value of the drawn line can be performed easily and with high accuracy.

In the droplet discharge amount measuring method of the present invention, a groove is formed in a portion of the droplet receiving portion where the line is to be drawn,
In the line drawing step, it is preferable that a droplet is landed in the groove.
Thereby, since the thickness of the drawn line can be made uniform along the longitudinal direction, the measurement accuracy of the droplet discharge amount can be further increased.

The jig for measuring a droplet discharge amount according to the present invention includes an insulating droplet receiving portion that receives a liquid material droplet discharged from a nozzle of a droplet discharge head;
A droplet discharge amount measuring jig having electrodes provided at a plurality of locations on the droplet receiving portion,
A line is drawn so as to connect two electrodes on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet receiving portion and the droplet discharge head, Used when performing a droplet discharge amount measurement method for measuring the electrical resistance value between two electrodes and estimating the droplet discharge amount of the nozzle on which the line is drawn based on the measured electrical resistance value It is characterized by that.

Thereby, the amount of one droplet discharged from the droplet discharge head can be measured for each nozzle. That is, it is possible to accurately know the discharge amount per droplet as a measurement value of a specific nozzle, not as an average value of all nozzles.
In particular, it is possible to measure the discharge amount for each nozzle when droplets are discharged from all nozzles of the droplet discharge head. In general, even when the same nozzle is used, the discharge amount differs between when the droplets are discharged from all the nozzles and when the droplets are discharged only from the nozzles. When drawing on the workpiece, droplets are ejected from almost all nozzles of the droplet ejection head, so in the present invention, the droplet ejection amount of the nozzle in a state close to the actual drawing state is measured. Can be extremely useful.

The droplet discharge amount measuring jig of the present invention preferably has a plurality of sets of electrodes corresponding to a plurality of nozzles of the droplet discharge head.
Thereby, the measurement about a some nozzle can be performed at once, and the time and labor which a measurement requires can be reduced significantly.
In the droplet discharge amount measuring jig of the present invention, it is preferable that a groove is formed in a portion of the droplet receiving portion where the line is to be drawn.
Thereby, since the thickness of the drawn line can be made uniform along the longitudinal direction, the measurement accuracy of the droplet discharge amount can be further increased.

The droplet discharge amount adjustment method of the present invention is a droplet discharge amount adjustment method for adjusting a droplet discharge amount of a droplet discharge head that discharges a liquid material as droplets from a nozzle,
An insulating droplet receiving portion that receives droplets and the droplet discharging head are moved relative to each other to repeatedly discharge droplets from a plurality of nozzles of the droplet discharging head. A line drawing process for drawing a plurality of lines in
An electrical resistance value measuring step of measuring an electrical resistance value of each of the plurality of lines,
By adjusting the driving voltage corresponding to each of the plurality of nozzles based on the measured electric resistance value of each of the plurality of lines, the droplet discharge amounts of the plurality of nozzles become as equal as possible. It is characterized by adjusting as follows.
Thereby, the discharge amount per droplet of each nozzle of the droplet discharge head can be made uniform. As a result, the film thickness drawn using this droplet discharge head can be controlled with high accuracy, and the quality of the product can be improved. Further, the above effect can be achieved by a very simple method.

The droplet discharge amount measuring device of the present invention is a droplet discharge amount measuring device that measures the droplet discharge amount of a droplet discharge head that discharges a liquid material as droplets from a nozzle,
An insulating droplet receiving portion for receiving the droplet;
An electrical resistance for measuring an electrical resistance value of a line drawn on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet discharging head and the droplet receiving portion A value measuring means;
And an estimation means for estimating a droplet discharge amount of a nozzle on which the line is drawn based on the measured electric resistance value of the line.

Thereby, the amount of one droplet discharged from the droplet discharge head can be measured for each nozzle. That is, it is possible to accurately know the discharge amount per droplet as a measurement value of a specific nozzle, not as an average value of all nozzles.
In particular, it is possible to measure the discharge amount for each nozzle when droplets are discharged from all nozzles of the droplet discharge head. In general, even when the same nozzle is used, the discharge amount differs between when the droplets are discharged from all the nozzles and when the droplets are discharged only from the nozzles. When drawing on the workpiece, droplets are ejected from almost all nozzles of the droplet ejection head, so in the present invention, the droplet ejection amount of the nozzle in a state close to the actual drawing state is measured. Can be extremely useful.

The drawing apparatus according to the present invention draws a liquid by discharging a liquid droplet from the nozzle and landing on the workpiece by relatively moving a droplet discharge head that discharges a liquid material as droplets from the nozzle and the workpiece. A drawing device to perform,
An insulating droplet receiving portion for receiving the droplet;
An electrical resistance for measuring an electrical resistance value of a line drawn on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet discharging head and the droplet receiving portion A value measuring means;
And an estimation means for estimating a droplet discharge amount of a nozzle on which the line is drawn based on the measured electric resistance value of the line.

Thereby, the amount of one droplet discharged from the droplet discharge head can be measured for each nozzle. That is, it is possible to accurately know the discharge amount per droplet as a measurement value of a specific nozzle, not as an average value of all nozzles.
In particular, it is possible to measure the discharge amount for each nozzle when droplets are discharged from all nozzles of the droplet discharge head. In general, even when the same nozzle is used, the discharge amount differs between when the droplets are discharged from all the nozzles and when the droplets are discharged only from the nozzles. When drawing on the workpiece, droplets are ejected from almost all nozzles of the droplet ejection head, so in the present invention, the droplet ejection amount of the nozzle in a state close to the actual drawing state is measured. Can be extremely useful.

Hereinafter, a droplet discharge amount measuring method, a droplet discharge amount measuring jig, a droplet discharge amount adjusting method, a droplet discharge amount measuring apparatus, and a drawing apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings. Explained.
FIG. 1 is a perspective view showing an embodiment of a drawing apparatus (inkjet drawing apparatus) equipped with a droplet discharge amount measuring apparatus of the present invention.
As shown in the drawing, the drawing apparatus 1 moves a carriage 103 on which one or a plurality of droplet discharge heads 2 are mounted, and the carriage 103 in one horizontal direction (hereinafter referred to as “X-axis direction”). A carriage moving mechanism (moving means) 104, a stage 106 for holding the workpiece 10A, and a stage moving mechanism for moving the stage 106 in a horizontal direction (hereinafter referred to as "Y-axis direction") perpendicular to the X-axis direction. (Moving means) 108 and control means 112 are provided.

A tank 101 that stores a liquid material 111 is installed in the vicinity of the drawing apparatus 1. The tank 101 and the carriage 103 are connected via a tube 110 serving as a flow path for feeding the liquid material 111. The liquid material 111 stored in each tank 101 is fed (supplied) to the droplet discharge head 2 of the carriage 103 by, for example, the force of compressed air.
Such a drawing apparatus 1 operates the stage moving mechanism 108 and the carriage moving mechanism 104, and relatively moves the stage 106 and the carriage 103, thereby scanning the droplet discharge head 2 along the workpiece 10A. In this apparatus, a droplet of the liquid material 111 is discharged from the nozzle 25 of the droplet discharge head 2 to draw a predetermined pattern on the workpiece 10A.

  The drawing device 1 is a device that can be used as a manufacturing device for various electro-optical devices. For example, a color filter substrate of a liquid crystal display device, a substrate with color elements such as an organic EL display device, an electron emission device, a PDP (Plasma Display). Panel) device, electrophoretic display device and the like, and can be used for metal wiring formation, lens formation, resist formation, light diffuser formation, and the like.

  In the present invention, the liquid material 111 includes a material for forming an object such as a color element film of a substrate with color elements, for example, and has a viscosity that can be discharged from the nozzle 25 of the droplet discharge head 2. It is what you have. In this case, it does not matter whether the material is aqueous or oily. Further, it is sufficient if it has fluidity (viscosity) that can be discharged from the nozzle 25, and even if a solid substance is dispersed, it is sufficient if it is a fluid as a whole. That is, the liquid material may be a solution in which the constituent material of the color element film is dissolved in a solvent or a dispersed dispersion (suspension or emulsion).

  Examples of materials that can be contained in the liquid material 111 include filter materials for color filters, fluorescent materials for forming EL light emitting layers in organic EL devices, fluorescent materials for forming phosphors in PDP devices, and electrophoretic display devices. In order to form a micro cell gap between two substrates, a migrating material for forming a migrating body, a bank material for forming a bank on the surface of the substrate, various coating materials, a liquid electrode material for forming an electrode Particle materials constituting the spacers, metal materials for forming metal wiring, lens materials for forming microlenses, resist materials, light diffusing materials for forming light diffusers, and the like.

  The operation of the carriage moving mechanism 104 in the drawing apparatus 1 is controlled by the control unit 112. The detailed configuration and function of the control unit 112 will be described later. The carriage moving mechanism 104 of this embodiment also has a function of adjusting the height by moving the carriage 103 along the Z-axis direction (vertical direction). Furthermore, the carriage moving mechanism 104 also has a function of rotating the carriage 103 around an axis parallel to the Z axis, whereby the angle of the carriage 103 around the Z axis can be finely adjusted.

The stage 106 has a plane parallel to both the X-axis direction and the Y-axis direction. The stage 106 is configured to fix or hold the workpiece 10A on the plane.
The stage moving mechanism 108 moves the stage 106 along the Y-axis direction orthogonal to both the X-axis direction and the Z-axis direction, and its operation is controlled by the control means 112. Furthermore, the stage moving mechanism 108 according to the present embodiment also has a function of rotating the stage 106 around an axis parallel to the Z axis, whereby the workpiece 10A placed on the stage 106 is rotated around the Z axis. The inclination can be finely adjusted to make it straight.

  As described above, the carriage 103 is moved in the X-axis direction by the carriage moving mechanism 104. On the other hand, the stage 106 is moved in the Y-axis direction by the stage moving mechanism 108. That is, the relative position between the workpiece 10A on the stage 106 and the carriage 103 is changed by the operation of the carriage moving mechanism 104 and the stage moving mechanism 108, so that the droplet discharge head 2 can be scanned relative to the workpiece 10A. it can.

The drawing apparatus 1 operates the stage moving mechanism 108 to move the workpiece 10A held on the stage 106 in the Y-axis direction and pass under the carriage 103, while the nozzles of each droplet discharge head 2 of the carriage 103. The liquid material 111 is operated to be ejected from 25. This operation is called “main scanning”.
When the width of the workpiece 10A in the X-axis direction is smaller than the width in the X-axis direction (hereinafter referred to as “total discharge width”) capable of discharging the liquid material 111 to the workpiece 10A as a whole of the carriage 103. By performing the main scanning of the carriage 103 and the workpiece 10A once, the liquid material 111 can be applied to the entire workpiece 10A, that is, the drawing can be performed.

  On the other hand, when the width of the workpiece 10A in the X-axis direction is larger than the entire discharge width of the carriage 103, the carriage 103 is operated in the X-axis direction by operating the carriage moving mechanism 104. After changing the relative positional relationship between the carriage 103 and the workpiece 10A in the X-axis direction, main scanning is performed again. Changing the relative positional relationship between the carriage 103 and the workpiece 10A in the X-axis direction is called “sub-scanning”. By repeatedly performing main scanning and sub-scanning, even if the width of the workpiece 10A in the X-axis direction is larger than the total discharge width of the carriage 103, the liquid material 111 is applied to the entire surface of the workpiece 10A. Giving, that is, drawing can be performed.

2A and 2B are diagrams showing the droplet discharge head 2 in the drawing apparatus 1 shown in FIG. 1, wherein FIG. 2A is a perspective view and FIG. 2B is a sectional side view. Hereinafter, the internal configuration of the droplet discharge head 2 will be described with reference to FIG.
A droplet discharge head 2 shown in FIG. 2 is an inkjet head having a nozzle row in which a large number of nozzles 25 for discharging droplets are arranged in a row.
The droplet discharge head 2 includes a vibration plate 126 and a nozzle plate 128 in which the nozzles 25 are formed. Between the diaphragm 126 and the nozzle plate 128, a liquid pool 129 in which the liquid material 111 supplied from the tank 101 through the hole 131 is always filled is located. A plurality of partition walls 122 are located between the diaphragm 126 and the nozzle plate 128. A portion surrounded by the diaphragm 126, the nozzle plate 128, and the pair of partition walls 122 is a cavity 120. Since the cavities 120 are provided corresponding to the nozzles 25, the number of the cavities 120 and the number of the nozzles 25 are the same. The liquid material 111 is supplied to the cavity 120 from the liquid pool 129 through the supply port 130 positioned between the pair of partition walls 122.

On the vibration plate 126, corresponding to the respective cavities 120, vibrators 124 are positioned as drive elements that change the pressure of the liquid material 111 filled in the cavities 120. The vibrator 124 includes a piezoelectric element 124C and a pair of electrodes 124A and 124B that sandwich the piezoelectric element 124C. By applying a driving voltage between the pair of electrodes 124A and 124B, the liquid material 111 is discharged from the corresponding nozzle 25. The shape of the nozzle 25 is adjusted so that the liquid material 111 is discharged from the nozzle 25 in the Z-axis direction.
The arrangement direction of the nozzles 25 of such a droplet discharge head 2 is a direction orthogonal to the Y-axis direction (main scanning direction).

The control means 112 may be configured to give a signal to each of the plurality of vibrators 124 independently of each other. That is, the volume of the liquid material 111 discharged from the nozzle 25 may be controlled for each nozzle 25 in accordance with a signal from the control unit 112.
The droplet discharge head 2 is not limited to a piezoelectric actuator as a driving element as shown in the figure, but uses an electrostatic actuator or an electrothermal conversion element and utilizes the thermal expansion of the liquid material 111. It may be configured to discharge droplets.

Next, the configuration of the control unit 112 will be described. As shown in FIG. 3, the control unit 112 includes an input buffer memory 200, a storage unit 202, a processing unit 204, a scanning drive unit 206, a head drive unit 208, a carriage position detection unit 302, and a stage position detection. Means 303.
The buffer memory 200 and the processing unit 204 are connected so that they can communicate with each other. The processing unit 204 and the storage unit 202 are connected to be communicable with each other. The processing unit 204 and the scan driving unit 206 are connected so as to communicate with each other. The processing unit 204 and the head driving unit 208 are connected so as to communicate with each other. The scanning drive unit 206 is connected to the carriage moving mechanism 104 and the stage moving mechanism 108 so as to communicate with each other. Similarly, the head driving unit 208 is connected to the droplet discharge head 2 so as to communicate with each other.

  The input buffer memory 200 receives data related to the position at which the liquid material 111 is ejected, that is, drawing pattern data, from the external information processing apparatus. The input buffer memory 200 supplies the drawing pattern data to the processing unit 204, and the processing unit 204 stores the drawing pattern data in the storage unit 202. The storage unit 202 includes a RAM, a magnetic recording medium, a magneto-optical recording medium, and the like.

The carriage position detection unit 302 detects the position (movement distance) of the carriage 103 in the X-axis direction and inputs the detection signal to the processing unit 204.
The stage position detection unit 303 detects the position (movement distance) of the stage 106, that is, the workpiece 10A in the Y-axis direction, and inputs the detection signal to the processing unit 204.
The carriage position detection unit 302 and the stage position detection unit 303 are constituted by, for example, a linear encoder, a laser length measuring device, or the like.

The processing unit 204 controls the operation of the carriage moving mechanism 104 and the stage moving mechanism 108 (closed loop control) via the scanning drive unit 206 based on the detection signals of the carriage position detecting unit 302 and the stage position detecting unit 303. The position of the carriage 103 and the position of the workpiece 10A are controlled.
Further, the processing unit 204 controls the moving speed of the stage 106, that is, the workpiece 10 </ b> A by controlling the operation of the stage moving mechanism 108.

Further, the processing unit 204 gives a selection signal SC for designating ON / OFF of the nozzle 25 at each ejection timing to the head driving unit 208 based on the drawing pattern data. The head drive unit 208 gives the droplet ejection head 2 an ejection signal ES necessary for ejecting the liquid material 111 based on the selection signal SC. As a result, the liquid material 111 is discharged as droplets from the corresponding nozzle 25 in the droplet discharge head 2.
The control means 112 may be a computer including a CPU, a ROM, and a RAM. In this case, the function of the control unit 112 is realized by a software program executed by a computer. Of course, the control means 112 may be realized by a dedicated circuit (hardware).

Next, the configuration and function of the head drive unit 208 in the control unit 112 will be described.
As shown in FIG. 4A, the head drive unit 208 includes one drive signal generation unit 203 and a plurality of analog switches AS. As shown in FIG. 4B, the drive signal generation unit 203 generates a drive signal DS. The potential of the drive signal DS changes with respect to the reference potential L over time. Specifically, the drive signal DS includes a plurality of ejection waveforms P that are repeated at the ejection cycle EP. Here, the discharge waveform P corresponds to a drive voltage waveform to be applied between a pair of electrodes of the corresponding vibrator 124 in order to discharge one droplet from the nozzle 25.
The drive signal DS is supplied to each input terminal of the analog switch AS. Each of the analog switches AS is provided corresponding to each of the nozzles 25. That is, the number of analog switches AS and the number of nozzles 25 are the same.

  The processing unit 204 supplies a selection signal SC indicating ON / OFF of the nozzle 25 to each analog switch AS. Here, the selection signal SC can take either a high level or a low level independently for each analog switch AS. On the other hand, the analog switch AS supplies the ejection signal ES to the electrode 124A of the vibrator 124 according to the drive signal DS and the selection signal SC. Specifically, when the selection signal SC is at a high level, the analog switch AS propagates the drive signal DS as the ejection signal ES to the electrode 124A. On the other hand, when the selection signal SC is at a low level, the potential of the ejection signal ES output from the analog switch AS becomes the reference potential L. When the drive signal DS is applied to the electrode 124A of the vibrator 124, the liquid material 111 is discharged from the nozzle 25 corresponding to the vibrator 124. A reference potential L is applied to the electrode 124B of each vibrator 124.

  In the case of the example shown in FIG. 4B, the high level in each of the two selection signals SC so that the ejection waveform P appears in the period 2EP that is twice the ejection period EP in each of the two ejection signals ES. And a low level period are set. As a result, the liquid material 111 is discharged from each of the two corresponding nozzles 25 at a period of 2EP. Further, a common drive signal DS from the common drive signal generation unit 203 is given to each of the vibrators 124 corresponding to these two nozzles 25. For this reason, the liquid material 111 is discharged from the two nozzles 25 at substantially the same timing.

FIG. 5 is a flowchart showing an embodiment of a droplet discharge amount measuring method and a droplet discharge amount adjusting method of the present invention, and FIGS. 6 and 7 are embodiments of a droplet discharge amount measuring jig of the present invention, respectively. FIG. 6 is a plan view and a side view showing the droplet discharge head 2.
In the droplet discharge amount measuring method of the present invention, a line 114 is drawn on the insulating droplet receiving portion 31, and then the electric resistance value of the line 114 is measured. Then, based on the measured electric resistance value of the line 114, the droplet discharge amount of the nozzle 25 on which the line 114 is drawn is estimated.

The electrical resistance value of the line 114 and the droplet discharge amount of the nozzle 25 on which the line 114 is drawn are generally in an inversely proportional relationship. This is because if the amount of one droplet 113 ejected from the nozzle 25 is large, the thickness of the drawn line 114 becomes thicker, so that the line 114 can easily conduct electricity and the electrical resistance of the line 114 becomes smaller. On the contrary, if the amount of one droplet 113 ejected from the nozzle 25 is small, the thickness of the drawn line 114 becomes thin, so that the line 114 is less likely to conduct electricity and the electrical resistance of the line 114 is Because it grows.
The drawing apparatus 1 includes an electric resistance value measuring unit 115 (not shown) including a resistance measuring device that measures the electric resistance value of the line 114. As shown in FIG. 3, the electrical resistance value measuring unit 115 is connected to the processing unit 204 of the control unit 112, and the measurement signal of the electrical resistance value measuring unit 115 is input to the processing unit 204.

The drawing apparatus 1 includes a droplet discharge amount measuring jig 3 shown in FIGS. The droplet discharge amount measuring method of the present invention is carried out using this droplet discharge amount measuring jig 3.
As shown in FIGS. 6 and 7, the droplet discharge amount measuring jig 3 is a flat plate member, and the upper surface thereof constitutes a droplet receiving portion 31. The surface of the droplet receiving portion 31 has an insulating property and prevents current from passing therethrough.

  On the droplet receiving portion 31, the same number of electrodes 32 and 33 used for measuring the electric resistance value of the line 114 as the nozzles 25 of the droplet discharge head 2 are provided. The electrodes 32 are arranged in a line at equal intervals, and the intervals are the same as the nozzle pitch of the droplet discharge head 2. Similarly, the electrodes 33 are also arranged in a line at equal intervals, and the intervals are the same as the nozzle pitch of the droplet discharge head 2. The row of electrodes 32 and the row of electrodes 33 are parallel to each other with a predetermined distance. That is, one set of electrodes 32 and 33 corresponds to each nozzle 25.

When performing the droplet discharge amount measuring method of the present invention, the droplet discharge amount measuring jig 3 as described above is mounted on the stage 106 instead of the workpiece 10A (step S01 in FIG. 7). ). At this time, the droplet discharge amount measuring jig 3 is set so that the arrangement direction of the electrodes 32 and 33 is parallel to the arrangement direction of the nozzles 25 of the droplet discharge head 2.
Thereafter, the stage moving mechanism 108 and the carriage moving mechanism 104 are operated to move the droplet discharge head 2 to the measurement position (step S02). That is, each nozzle 25 is positioned above each electrode 32.

  Next, the line 114 is drawn between the electrodes 32 and 33 by the droplet discharge head 2 (step S03). That is, as shown in FIG. 7, the stage moving mechanism 108 is operated to move each nozzle 25 of the droplet discharge head 2 relatively from the electrode 32 toward the electrode 33, while the liquid is discharged from each nozzle 25. The droplet 113 is repeatedly discharged. At this time, the same number of droplets 113 are ejected from each nozzle 25. Thereby, as shown in FIG. 8, each electrode 32 and each electrode 33 are connected by a line 114 drawn by the corresponding nozzle 25.

Since the line 114 is made of the liquid material 111, the line 114 is in a liquid state immediately after drawing. And if the liquid material 111 which comprises the line 114 is dried and the solvent in the liquid material 111 is evaporated, the line 114 will solidify or harden | cure and will be in a solid state.
In the present invention, the measurement of the electric resistance value of the line 114 may be performed when the line 114 is in a liquid state, or may be performed after the line 114 is dried and solidified or cured.

When the material contained in the liquid material 111 is not conductive (for example, a filter material for a color filter or a fluorescent material for forming an EL light emitting layer in an organic EL device), the line 114 is dried. When solidified or cured, the line 114 has almost no conductivity. Therefore, it is preferable to measure the electric resistance value while the line 114 is in a liquid state.
On the other hand, when the material contained in the liquid material 111 is conductive (for example, a metal material for forming a metal wiring), the line 114 is solidified or cured. Since it has electroconductivity, you may measure an electrical resistance value after drying.

When measuring the electrical resistance value of the line 114, a measurement probe (not shown) provided in the resistance measuring device of the electrical resistance value measuring means 115 is applied to the electrodes 32 and 33 at both ends of the line 114 (step S04). ) The electrical resistance value is measured for each line 114. Signals indicating these measured values are transferred to the control means 112 (step S05).
As described above, the electrical resistance value of each line 114 and the droplet discharge amount of the nozzle 25 on which the line 114 is drawn are generally in an inversely proportional relationship. Therefore, the control unit 112 can estimate the magnitude relationship (ratio) of the droplet discharge amount of the nozzle 25 that draws the line 114 by comparing the electric resistance value of each line 114. As described above, the control unit 112 according to the present embodiment is an estimation unit that estimates the magnitude relationship (ratio) of the droplet discharge amount of the nozzle 25 that has drawn this line based on the measured electric resistance value of the line 114. Function.
The control means 112 adjusts the driving voltage to the vibrator 124 corresponding to each of the plurality of nozzles 25 based on the electric resistance value of each line 114 measured by the electric resistance value measuring means 115, thereby making it possible to adjust all the nozzles. It adjusts so that the discharge amount per drop of 25 may become equal as much as possible (step S06).

  For example, when the electric resistance value of a certain line 114 is 10% higher than a reference electric resistance value (for example, an average value), the droplet discharge amount of the nozzle 25 on which the line 114 is drawn is a reference value ( 10% less than the average value), and in order to correct this, the magnitude of the drive voltage to the vibrator 124 corresponding to the nozzle 25 is increased by 10%. Conversely, when the electrical resistance value of a certain line 114 is 10% lower than the reference electrical resistance value, the droplet discharge amount of the nozzle 25 on which the line 114 is drawn is lower than the reference value (average value). Since it is estimated that it is 10% higher, in order to correct this, the magnitude of the drive voltage to the vibrator 124 corresponding to the nozzle 25 is lowered by 10%.

By performing such adjustment, the discharge amount per droplet of all the nozzles 25 of the droplet discharge head 2 can be made uniform. As a result, the film thickness formed using the drawing apparatus 1 can be reduced. It can be controlled with high accuracy, and the quality of the product can be improved.
For example, when a color element film such as a filter film or a light emitting film is formed on a color element (pixel) of a color element substrate such as a color filter substrate of a liquid crystal display device or an organic EL display device, the film of the color element film The thickness can be made uniform over all color elements, and color unevenness can be prevented.
When the droplet discharge amount is measured again after the adjustment of the droplet discharge amount of each nozzle 25, the process returns to step S01, and step S01 and subsequent steps are executed again (step S07). When the re-measurement is not performed, the droplet discharge amount measurement method and the droplet discharge amount adjustment method are terminated.

  According to the present invention as described above, it is possible to estimate the magnitude relationship (ratio) of the ejection amount of each nozzle 25 when the droplet 113 is ejected from all the nozzles 25 of the droplet ejection head 2. Generally, even when the same nozzle 25 is used, the discharge amount is different between the case where the droplet 113 is discharged from all the nozzles 25 and the case where the droplet 113 is discharged only from the nozzle 25. When drawing on the workpiece 10A, since the droplets 113 are discharged from almost all the nozzles 25 of the droplet discharge head 2, in the present invention, the droplet discharge amount in a state close to the actual drawing state is set for each. It can be measured for each nozzle 25 and is extremely useful.

  In the embodiment described above, based on the measured electric resistance value of each line 114, the magnitude relation (ratio) of the droplet discharge amounts of the plurality of nozzles 25 that draw the lines 114 is estimated. In this way, the droplet discharge amount itself may be estimated. That is, the relationship between the electric resistance value of the line 114 and the total amount of the liquid material 111 required to draw the line 114 is clarified by experiments in advance, and a mathematical expression or a lookup table representing the relationship is stored in the storage unit 202. Remember it. When the measured electric resistance value of the line 114 is input to the control unit 112, the control unit 112 uses the mathematical formula or the lookup table to calculate the total amount of the liquid material 111 required to draw the line 114. And dividing this value by the total number of droplets 113 required to draw the line 114, the volume per droplet of the droplet 113 ejected from the nozzle 25 that has drawn the line 114 is obtained. Can be sought. By performing this procedure for each line 114, the volume per droplet of the droplet 113 to be ejected can be obtained for each nozzle 25 of the droplet ejection head 2.

  In the present embodiment, when the droplet discharge amount measuring method is performed, the droplet discharge amount measuring jig 3 is placed on the stage 106, but the present invention is not limited to this configuration. In the present invention, when the droplet receiving portion 31 on which the electrodes 32 and 33 are formed is fixedly installed outside the drawing region of the drawing apparatus 1 and the droplet discharge amount measuring method is performed, the droplet discharge head is used. The measurement may be performed by moving 2 to the sky above the installation portion of the electrodes 32 and 33.

In the present invention, a groove may be formed in a portion of the droplet receiving portion 31 where the line 114 is to be drawn, and the droplet 113 may be landed in the groove. Thereby, since the thickness of the drawn line 114 can be made uniform along the longitudinal direction, the measurement accuracy of the droplet discharge amount can be further increased. This groove can be formed by providing a bank (bank) on the droplet receiving portion 31.
In the present invention, the electrodes 32 and 33 may not be provided. In this case, a resistance measuring probe may be directly applied to both ends of the drawn line 114.

  As described above, the droplet discharge amount measuring method, the droplet discharge amount measuring jig, the droplet discharge amount adjusting method, the droplet discharge amount measuring apparatus, and the drawing apparatus of the present invention have been described with respect to the illustrated embodiments. However, the present invention is not limited to this. In addition, each component constituting the droplet discharge amount measuring jig, the droplet discharge amount measuring apparatus, and the drawing apparatus of the present invention can be replaced with any configuration that can exhibit the same function. Moreover, arbitrary components may be added.

The perspective view which shows embodiment of the drawing apparatus carrying the droplet discharge amount measuring apparatus of this invention. 2A and 2B are diagrams showing a droplet discharge head in the drawing apparatus shown in FIG. 1, in which FIG. The block diagram which shows the structure of the control means in the drawing apparatus shown in FIG. (A) is a schematic diagram showing a head drive unit, (b) is a timing chart showing a drive signal, a selection signal and an ejection signal in the head drive unit. 3 is a flowchart showing an embodiment of a droplet discharge amount measuring method and a droplet discharge amount adjustment method of the present invention. The top view which shows embodiment of the jig for droplet discharge amount measurement of this invention, and a droplet discharge head. The side view which shows embodiment of the jig for droplet discharge amount measurement of this invention, and a droplet discharge head. The top view which shows the state with which the liquid material was filled in the groove | channel of the jig for droplet discharge amount measurement shown in FIG. 6 and FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Drawing apparatus 2 ... Droplet discharge head 25 ... Nozzle 3 ... Droplet discharge amount measuring jig 31 ... Droplet receiving part 32, 33 ... Electrode 101 ... Tank 103 ... Carriage 104 ... ... Carriage moving mechanism 106 ... Stage 108 ... Stage moving mechanism 110 ... Tube 111 ... Liquid material 112 ... Control means 113 ... Droplet 114 ... Line 115 ... Electric resistance measurement means 120 ... Cavity 122 …… Branch 124 …… Vibrator 124A, 124B …… Electrode 124C …… Piezo element 126 …… Vibration plate 128 …… Nozzle plate 129 …… Puddle 130 …… Supply port 131 …… Hole 200 …… Buffer memory 202… ... Storage means 203... Drive signal generation unit 204... Processing unit 206. ... Head drive unit 302 ... Carriage position detection means 303 ... Stage position detection means 10A ... Work AS ... Analog switch DS ... Drive signal SC ... Selection signal ES ... Discharge signal

Claims (12)

A droplet discharge amount measuring method for measuring a droplet discharge amount of a droplet discharge head for discharging a liquid material as droplets from a nozzle,
Line drawing for drawing a line on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the insulating droplet receiving portion that receives the droplet and the droplet discharge head Process,
An electrical resistance value measuring step for measuring an electrical resistance value of the line,
A droplet discharge amount measuring method, comprising: estimating a droplet discharge amount of a nozzle that has drawn the line based on the measured electric resistance value of the line.   The droplet discharge amount measuring method according to claim 1, wherein the electric resistance value measuring step is performed in a state where the liquid material of the line is dried and solidified or cured.   The droplet discharge amount measuring method according to claim 1, wherein the electric resistance value measuring step is performed while the liquid material of the line is in a liquid state. In the line drawing step, a plurality of lines are drawn on the droplet receiving portion by discharging droplets from a plurality of nozzles of the droplet discharge head;
In the electrical resistance value measuring step, the electrical resistance value of each of the plurality of lines is measured,
4. The droplet discharge amount measuring method according to claim 1, wherein the droplet discharge amount of each of the plurality of nozzles is estimated based on the measured electric resistance value of each line. Electrodes are provided at a plurality of locations on the droplet receiving portion,
In the line drawing step, a line is drawn so as to connect the two electrodes on the droplet receiving part,
5. The droplet discharge amount measuring method according to claim 1, wherein in the electrical resistance value measuring step, an electrical resistance value between the two electrodes is measured. A groove is formed in a portion of the droplet receiving portion where the line is to be drawn,
The droplet discharge amount measuring method according to claim 1, wherein in the line drawing step, a droplet is landed in the groove. An insulating droplet receiving portion for receiving droplets of the liquid material discharged from the nozzle of the droplet discharge head;
A droplet discharge amount measuring jig having electrodes provided at a plurality of locations on the droplet receiving portion,
A line is drawn so as to connect two electrodes on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet receiving portion and the droplet discharge head, Used when performing a droplet discharge amount measurement method for measuring the electrical resistance value between two electrodes and estimating the droplet discharge amount of the nozzle on which the line is drawn based on the measured electrical resistance value A jig for measuring a droplet discharge amount.   8. The droplet discharge amount measuring jig according to claim 7, comprising a plurality of sets of electrodes corresponding to a plurality of nozzles of the droplet discharge head.   9. The droplet discharge amount measuring jig according to claim 7, wherein a groove is formed in a portion of the droplet receiving portion where the line is to be drawn. A droplet discharge amount adjustment method for adjusting a droplet discharge amount of a droplet discharge head that discharges liquid material as droplets from a nozzle,
An insulating droplet receiving portion that receives droplets and the droplet discharging head are moved relative to each other to repeatedly discharge droplets from a plurality of nozzles of the droplet discharging head. A line drawing process for drawing a plurality of lines in
An electrical resistance value measuring step of measuring an electrical resistance value of each of the plurality of lines,
By adjusting the drive voltage corresponding to each of the plurality of nozzles based on the measured electric resistance value of each of the plurality of lines, the droplet discharge amounts of the plurality of nozzles become as equal as possible. A method for adjusting a droplet discharge amount, wherein the adjustment is performed as described above. A droplet discharge amount measuring device that measures a droplet discharge amount of a droplet discharge head that discharges liquid material as droplets from a nozzle,
An insulating droplet receiving portion for receiving the droplet;
An electrical resistance for measuring an electrical resistance value of a line drawn on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet discharging head and the droplet receiving portion A value measuring means;
An apparatus for measuring a droplet discharge amount, comprising: an estimation unit that estimates a droplet discharge amount of a nozzle that has drawn the line based on the measured electric resistance value of the line. A drawing apparatus that performs drawing by relatively moving a droplet discharge head that discharges a liquid material as droplets from a nozzle, and discharging the droplets from the nozzle and landing on the workpiece,
An insulating droplet receiving portion for receiving the droplet;
An electrical resistance for measuring an electrical resistance value of a line drawn on the droplet receiving portion by repeatedly discharging droplets from the nozzle while relatively moving the droplet discharging head and the droplet receiving portion A value measuring means;
A drawing apparatus comprising: an estimation unit that estimates a droplet discharge amount of a nozzle that has drawn the line based on the measured electric resistance value of the line.

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