JP2008142944A - Nozzle plate manufacturing method, liquid droplet ejection head manufacturing method and liquid droplet ejector manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure a stable ejection performance even when liquid droplets of a minute amount are ejected. <P>SOLUTION: A nozzle 118 with both a funnel part 151 in the form of a funnel opened to one surface 128a of a plate 128 and an equal diameter part 152 extending by an equal diameter from a bottom 151a of the funnel part and opened to the other surface 128b of the plate is formed in the plate 128. The manufacturing method has a first process of pressing one surface of the plate by a punch P with an outline shape corresponding to the funnel part and the equal diameter part, thereby forming the funnel part and the equal diameter part, a second process of opening the equal diameter part by removing the other surface side of the plate, a third process of measuring a length of the equal diameter part formed in the plate, and a fourth process of removing the other surface of the plate by a thickness according to the measured length of the equal diameter part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a nozzle plate manufacturing method, a droplet discharge head manufacturing method, and a droplet discharge apparatus manufacturing method.

  In the droplet discharge type droplet discharge head, the flow path communicating with the ink pressurizing chamber is covered with the nozzle plate, and the ink is discharged from the nozzle opened in the ink flow path portion. In order to stabilize the meniscus and attenuate the pressure wave so that the ink is stably ejected in the axial direction of the nozzle, the nozzle formed on the nozzle plate is usually a straight line extending to the ejection side with the same diameter. And a funnel-shaped diameter-expanded portion that gradually increases in diameter from the straight portion on the flow path side. As a method for forming such a nozzle, for example, in Patent Document 1, a punch having a shape corresponding to the funnel shape of the nozzle is combined with a die having a chamfered portion in a hole slightly larger than the narrow diameter portion at the tip of the punch, It is described that it is formed by passing a punch through a nozzle plate.

Also, in Patent Document 2, the tip of a funnel-shaped narrow-diameter portion is projected with a punch protruding in a cone shape to form a hole shape inside the nozzle plate, and then the nozzle plate protruding portion on the ink discharge side is polished. Techniques for finishing holes are disclosed.
Japanese Patent Laid-Open No. 5-229127 JP 2000-289211 A

However, the following problems exist in the conventional technology as described above.
In a head that discharges micro droplets, it is known that the length of the straight portion of the nozzle greatly affects the discharge performance and the droplet amount fluctuates.
For this reason, variations in droplet discharge amount, which has not been a problem with conventional droplet amounts for printers (picoliter level), are applied to electronic device manufacturing by ejecting very small amounts (femtoliter level) of droplets. The influence on the performance (resistance, mobility, light emission performance, etc.) of electronic devices cannot be ignored.
However, in the techniques described in Patent Documents 1 and 2 described above, variations in length of the straight portion are large, and it is difficult to ensure stable discharge performance.

  The present invention has been made in consideration of the above points, and an object of the present invention is to provide a nozzle plate manufacturing method, a droplet discharge head manufacturing method, and a droplet discharge device manufacturing method capable of ensuring stable discharge performance. And

In order to achieve the above object, the present invention employs the following configuration.
The nozzle plate manufacturing method of the present invention includes a nozzle having a funnel-like funnel portion opened on one surface of the plate and a same-diameter portion extending from the bottom of the funnel portion with the same diameter and opening on the other surface of the plate. A nozzle plate manufacturing method for forming on a plate, wherein the funnel portion and the same diameter portion are formed by pressurizing one surface of the plate with a punch having a contour shape corresponding to the funnel portion and the same diameter portion. A step, a second step of removing the other surface side of the plate to open the same-diameter portion, a third step of measuring the length of the same-diameter portion formed on the plate, and the measured same-diameter And a fourth step of removing the other surface of the plate with a thickness corresponding to the length of the part.
Therefore, in the nozzle plate manufacturing method of the present invention, if the length of the same diameter portion formed on the plate is different from the predetermined length, the difference between the measured length of the same diameter portion and the predetermined length, By removing the surface, the same diameter portion can be adjusted to a predetermined length. Therefore, in the present invention, stable ejection performance can be ensured even when a very small amount of droplets is ejected.

Moreover, in this invention, the procedure which measures the length of the said same diameter part based on the thickness of the said plate in the said 3rd process and the length of the said funnel part can be employ | adopted suitably.
Thereby, it becomes possible to easily measure the length of the same diameter portion, which is difficult to measure directly in the present invention, by calculating the difference between the thickness of the plate and the length of the funnel portion.

In said procedure, the procedure which measures the length of the said funnel part can be employ | adopted suitably based on the focal depth of the said one surface by an optical length measuring device, and the focal depth of the bottom part of the said funnel part.
Therefore, in the nozzle plate manufacturing method of the present invention, the length of the same diameter portion can be easily measured by measuring from one side of the plate, the measuring process can be performed in a short time, and the efficiency of the manufacturing process Can contribute to Further, in the present invention, the length of the same diameter portion can be measured without contact, and it is possible to prevent adverse effects such as damage to the nozzle plate due to contact.

Moreover, in this invention, the procedure which removes the specific area | region containing the said nozzle among the said other surfaces in the said 4th process can be employ | adopted suitably.
Therefore, in the nozzle plate manufacturing method of the present invention, a step is generated between the specific region and the surrounding other surface, so that the possibility of contact with the nozzle is reduced even when printing paper or the like causes a paper jam. Even when the paper comes into contact with the nozzle, the contact pressure can be reduced, and it is possible to suppress the discharge performance from being deteriorated due to the nozzle being damaged due to the contact with the paper or the like.

As the length of the contour shape of the punch corresponding to the same-diameter portion, a configuration that is larger than a predetermined length of the same-diameter portion formed on the plate can be suitably employed.
Therefore, in the nozzle plate manufacturing method of the present invention, the length adjustment allowance for the same diameter portion can be ensured, so that the length of the same diameter portion can be reliably adjusted to a predetermined length.

The droplet discharge head manufacturing method of the present invention is a method for manufacturing a droplet discharge head having a nozzle plate, wherein the nozzle plate is manufactured by the nozzle plate manufacturing method described above. is there.
Therefore, in the droplet discharge head manufacturing method of the present invention, the same diameter portion of the nozzle can be adjusted to a predetermined length, so that even when a small amount of droplet is discharged, stable discharge performance is achieved. Therefore, it is possible to manufacture a droplet discharge head with high drawing accuracy.

The method for manufacturing a droplet discharge device of the present invention is a method for manufacturing a droplet discharge device having a droplet discharge head, and the droplet discharge head is manufactured by the method for manufacturing a droplet discharge head described above. It is characterized by.
Therefore, in the method for manufacturing a droplet discharge device according to the present invention, the same diameter portion of the nozzle can be adjusted to a predetermined length, so that stable discharge performance can be achieved even when a small amount of droplet is discharged. Therefore, it is possible to manufacture a droplet discharge device with high drawing accuracy.

Embodiments of a nozzle plate manufacturing method, a droplet discharge head manufacturing method, and a droplet discharge device manufacturing method according to the present invention will be described below with reference to FIGS.
In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.

(Droplet discharge device)
First, a droplet discharge device used in a nozzle plate manufacturing method, a droplet discharge head manufacturing method, and a droplet discharge device manufacturing method according to the present invention will be described with reference to FIGS.
A droplet discharge device 1 shown in FIG. 1 is basically an ink jet device. More specifically, the droplet discharge device 1 includes a tank 101 that holds the liquid material 111, a tube 110, a ground stage GS, a discharge head unit (droplet discharge head) 103, a stage 106, a first The position control device 104, the second position control device 108, the control unit 112, the light irradiation device 140, and the support unit 104a are provided.

The discharge head unit 103 holds a head 114 (see FIG. 2). The head 114 ejects droplets of the liquid material 111 in response to a signal from the control unit 112. Note that the head 114 in the discharge head unit 103 is connected to the tank 101 by the tube 110, and thus the liquid material 111 is supplied from the tank 101 to the head 114.
The stage 106 provides a plane for fixing a substrate (described later). Further, the stage 106 also has a function of fixing the position of the substrate using a suction force.

  The first position control device 104 is fixed at a predetermined height from the ground stage GS by the support portion 104a. The first position control device 104 has a function of moving the ejection head unit 103 along the X-axis direction and the Z-axis direction orthogonal to the X-axis direction in accordance with a signal from the control unit 112. Furthermore, the first position control device 104 also has a function of rotating the ejection head unit 103 around an axis parallel to the Z axis. Here, in the present embodiment, the Z-axis direction is a direction parallel to the vertical direction (that is, the direction of gravitational acceleration).

  The second position control device 108 moves the stage 106 on the ground stage GS in the Y-axis direction according to a signal from the control unit 112. Here, the Y-axis direction is a direction orthogonal to both the X-axis direction and the Z-axis direction.

  As described above, the ejection head unit 103 is moved in the X-axis direction by the first position control device 104. Then, the substrate is moved in the Y-axis direction together with the stage 106 by the second position control device 108. As a result, the relative position of the head 114 with respect to the substrate changes. More specifically, by these operations, the ejection head unit 103, the head 114, or the nozzle 118 (see FIG. 2) maintains a predetermined distance in the Z-axis direction with respect to the substrate while maintaining the X-axis direction and the Y-axis. Move relatively in the axial direction, that is, scan relatively. “Relative movement” or “relative scanning” means that at least one of the side on which the liquid material 111 is discharged and the side on which the discharged material lands (discharged part) moves relative to the other. .

  The control unit 112 is configured to receive ejection data representing a relative position at which droplets of the liquid material 111 are to be ejected from an external information processing apparatus. The control unit 112 stores the received discharge data in an internal storage device, and controls the first position control device 104, the second position control device 108, and the head 114 in accordance with the stored discharge data. To do. The ejection data is data for applying the liquid material 111 in a predetermined pattern on the substrate. In the present embodiment, the ejection data has the form of bitmap data.

The droplet discharge device 1 having the above configuration moves the nozzle 118 (see FIG. 2) of the head 114 relative to the substrate according to the discharge data, and also supplies the liquid material 111 from the nozzle 118 toward the discharge target portion. Discharge. The relative movement of the head 114 by the droplet discharge device 1 and the discharge of the liquid material 111 from the head 114 may be collectively referred to as “application scanning” or “discharge scanning”.
The light irradiation device 140 is a device that irradiates the liquid material 111 applied to the substrate with ultraviolet light. The control unit 112 controls ON / OFF of the ultraviolet irradiation of the light irradiation device 140.

  As shown in FIGS. 2A and 2B, the head 114 in the droplet discharge device 1 is an inkjet head having a plurality of nozzles 118. Specifically, the head 114 includes a diaphragm 126, a plurality of nozzles 118, a nozzle plate (plate) 128 that defines the openings of the plurality of nozzles 118, a liquid pool 129, a plurality of partition walls 122, A plurality of cavities 120 and a plurality of vibrators 124 are provided.

The liquid pool 129 is located between the diaphragm 126 and the nozzle plate 128. The liquid pool 129 is always filled with the liquid material 111 supplied from an external tank (not shown) through the hole 131. The The plurality of partition walls 122 are located between the diaphragm 126 and the nozzle plate 128.
The cavity 120 is a part surrounded by the diaphragm 126, the nozzle plate 128, and the pair of partition walls 122. Since the cavities 120 are provided corresponding to the nozzles 118, the number of the cavities 120 and the number of the nozzles 118 are the same. The liquid material 111 is supplied from the liquid pool 129 to the cavity 120 through the supply port 130 positioned between the pair of partition walls 122.

As shown in FIG. 2B, the nozzle 118 includes a funnel-shaped funnel portion 151 that opens on a surface (one surface) 128a on the cavity 120 side (liquid pool 129 side) of the nozzle plate 128, and a bottom portion of the funnel portion (the outermost portion). A straight portion (same diameter portion) 152 that extends from the small diameter portion) to the same diameter and opens to the surface (other surface) 128b side of the droplet discharge side of the nozzle plate 128 is provided. The straight portion 152 is open to the nozzle surface 128c from which a step is generated by removing the nozzle peripheral region (specific region) including the nozzle 118 from the surface 128b.
The straight portion 152 is set to have a diameter (nozzle diameter) of 10 μm and a length of 5 μm, for example. Accordingly, the funnel portion 151 is a taper that gradually increases in diameter from the bottom portion formed to have a diameter of about 10 μm toward the surface 128a. It is formed in a shape.

Each of the plurality of vibrators 124 is positioned on the diaphragm 126 so as to correspond to each cavity 120. Each of the plurality of vibrators 124 includes a piezoelectric element 124C and a pair of electrodes 124A and 124B that sandwich the piezoelectric element 124C. When the control unit 112 applies a driving voltage between the pair of electrodes 124A and 124B, the droplet D of the liquid material 111 is ejected from the corresponding nozzle 118. Here, the volume of the material discharged from the nozzle 118 is variable, for example, from a femtoliter level to a picoliter level. As described above, the shape of the nozzle 118 (particularly, the length of the straight portion 152) is adjusted so that the droplet of the liquid material 111 is ejected from the nozzle 118 in the Z-axis direction.
The ejection unit 127 may include an electrothermal conversion element instead of the piezo element. That is, the discharge unit 127 may have a configuration for discharging a material by utilizing thermal expansion of the material by the electrothermal conversion element.

(Nozzle forming device)
Next, an apparatus for forming the nozzle 118 on the nozzle plate 128 will be described with reference to FIG.
A nozzle forming apparatus 200 shown in FIG. 3A includes a lower jig 201 that supports the nozzle plate 128 from below, and a holding jig 202 that holds the base BP of the punch P and moves away from and approaches the lower jig 201. And a holding jig 202 that is connected to the holding jig 202 via a spring 210 and presses the nozzle plate 128 with the urging force of the spring 210 when the holding jig 202 is lowered. Is done. The holding jig 202, the holding jig 203, and the spring 210 constitute an upper jig.
A through hole 201a is formed in the lower jig 201 corresponding to the position of the punch P (nozzle 118).

FIG. 2B is a partially enlarged view showing the tip of the punch P.
As shown in this figure, a funnel contour portion 151P having a contour shape corresponding to the funnel portion 151 of the nozzle 118 and a straight contour portion 152P having a contour shape corresponding to the straight portion 152 are provided at the tip of the punch P. It has been. The length LP of the straight contour 152P in the punch P is formed to be larger than the length L (predetermined length; see FIG. 2B) of the straight 152 in the nozzle 118.

Next, a procedure for forming the nozzle 118 shown in FIG. 2 on the nozzle plate 128 using the nozzle forming apparatus 200 will be described with reference to FIG.
First, as shown in FIG. 3, a nozzle plate 128 made of, for example, a stainless material is placed on the lower jig 201, and then the holding jig 202 is lowered so that the nozzle plate 128 is biased by the spring 210. Is pressed between the lower jig 201 and the holding jig 203 by the punch P against the surface 128a.

  At this time, as shown in FIG. 4A, the punch P is lowered by a stroke in which the straight contour portion 152 </ b> P of the punch P does not penetrate the nozzle plate 128. Thus, in the nozzle plate 128, the funnel portion 151, the straight portion 152, and the protruding portion 153 that protrudes from the surface 128b to the through hole 201a according to the contour shapes of the funnel contour portion 151P and the straight contour portion 152P are formed. (First step).

  Subsequently, the punch P is detached from the nozzle plate 128, and then, as shown in FIG. 4B, the surface 128b is polished (ground) to open the straight portion 152 (second step), and the nozzle 118 Form. Thereafter, the nozzle plate 128 on which the nozzle 118 is formed is placed on an optical length measuring device such as a tool microscope, and the focal depth of the upper surface 128a (that is, the focal depth of the upper portion of the funnel portion 151) and the funnel portion 151 are set. The depth of focus of the bottom 151a is measured. Then, the height of the funnel portion 151 is calculated from the difference between the measured focal depths, and the length of the straight portion 152 (hereinafter referred to as the straight length as appropriate) is calculated from the difference between the height of the funnel portion 151 and the plate pressure of the nozzle plate 128. Is calculated (measured) (third step).

Subsequently, the surface 128b of the nozzle plate 128 is removed based on the measured length of the straight portion 152 (fourth step).
Specifically, when the measured length is LK (see FIG. 4B) with respect to the predetermined length L of the straight portion 152 (see FIG. 2B), the surface 128b is made thicker. Remove with LC. This thickness LC is expressed by the following equation.
LC = LK-L (1)

The thickness LC obtained by this equation (1) is removed from the surface 128b for the nozzle peripheral region (specific region).
As the removal process for the surface 128b, electric discharge machining using a discharge electrode, laser machining, sandblasting, or the like can be used.
As a result, a nozzle surface 128c having a step with respect to the surface 128b and opening the nozzle 118 is formed in the peripheral region of the nozzle 118. In this nozzle 118, the straight portion 151 is set to a predetermined length L.

  As described above, in this embodiment, the length of the straight portion 152 in the nozzle 118 once formed on the nozzle plate 128 is measured, and the thickness of the nozzle plate 128 is adjusted according to the measured length. Even if the straight length varies depending on (punch mounting accuracy, pressurizing force, pressurizing time, accuracy of the lower jig 201, plate material characteristics of the nozzle plate 128), a constant straight length can always be ensured with high accuracy. It becomes possible.

  For this reason, in the present embodiment, even when a very small amount of femtoliter level liquid droplets are ejected from the ejection head unit 103, stable ejection performance (ejection characteristics) can be ensured, and the ejection head unit 103 with high drawing accuracy. And the droplet discharge device 1 can be obtained. In addition, manufacturing a highly accurate punch may cause an increase in cost and a decrease in productivity, but in this embodiment, the conventional punch technology can be used as it is.

  In the present embodiment, since the straight length that is difficult to measure is obtained based on the thickness of the nozzle plate 128 and the length of the funnel portion 151, the straight length can be easily and quickly measured. is there. In particular, in this embodiment, since the length of the funnel portion 151 is measured based on the depth of focus by the optical length measuring device, measurement from the same surface can be performed in a non-contact manner, and the measurement process can be performed in a short time. Thus, it is possible to prevent the adverse effect such as damage to the nozzle plate 128 due to contact with the nozzle plate 128 during length measurement using the contact.

  In the present embodiment, when adjusting the straight length, only a specific area around the nozzle is removed from the surface 128b, so that a step can be formed between the surface 128b and the nozzle surface 128c. For example, when the droplet discharge device 1 is used in a printer, even when printing paper or the like causes a paper jam, the possibility of contact with the nozzle 118 is reduced, and even when the paper contacts the nozzle 118, the contact pressure is reduced. It is possible to reduce the discharge performance due to the nozzle 118 being damaged by contact with paper or the like.

  Furthermore, in this embodiment, since the length of the straight contour portion 152P in the punch P is larger than the length L of the straight portion 152 in the nozzle 118, an adjustment allowance for the straight length can be secured, so the straight length Can be reliably adjusted to a predetermined length.

  In addition, in the present embodiment, by adjusting as described above, the straight lengths of the plurality of nozzles 118 in the discharge head unit 103 can be made uniform, and the respective discharge amounts can be made uniform. The film thickness of the film formed by using the droplet discharge device 1 can be controlled with high accuracy, and the quality of the product can be improved.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above embodiment, the length of the straight portion 152 is measured using the thickness of the nozzle plate 128 and the length of the funnel portion 151. However, the length may be directly measured, or optical length measurement may be performed. A length measuring device other than the measuring device may be used. Further, the processing method for forming the nozzle surface 128c shown in the above embodiment is an example, and other processing methods may be used.

  Further, in the above embodiment, after measuring the straight length of the nozzle 118, the specific area of the surface 128b is removed and the nozzle surface 128c is measured. Further, a step between the surface 128b and the nozzle surface 128c is measured. By doing so, the straight length may be remeasured and readjusted.

It is a schematic diagram of the droplet discharge device according to the present invention. (A) And (b) is a schematic diagram of the head in a droplet discharge device. It is a schematic diagram of a nozzle formation apparatus. It is process drawing which shows the procedure which forms a nozzle.

Explanation of symbols

  P ... punch, 1 ... droplet ejection device, 103 ... ejection head part (droplet ejection head), 118 ... nozzle, 128 ... nozzle plate (plate), 128a ... surface (one surface), 128b ... surface (other surface), 151 ... funnel part, 151a ... bottom part, 152 ... straight part (same diameter part)

Claims (7)

Nozzle plate manufacturing for forming a nozzle in the plate having a funnel-like funnel portion opening on one side of the plate and a same diameter portion extending from the bottom of the funnel portion with the same diameter and opening on the other surface side of the plate A method,
A first step of pressurizing one surface of the plate with a punch having a contour shape corresponding to the funnel part and the same diameter part to form the funnel part and the same diameter part;
A second step of removing the other surface side of the plate and opening the same-diameter portion;
A third step of measuring the length of the same-diameter portion formed on the plate;
And a fourth step of removing the other surface of the plate with a thickness corresponding to the measured length of the same diameter portion. In the nozzle plate manufacturing method of Claim 1,
In the third step, the length of the same-diameter portion is measured based on the thickness of the plate and the length of the funnel portion. In the nozzle plate manufacturing method of Claim 2,
A method for producing a nozzle plate, comprising: measuring a length of the funnel portion based on a focal depth of the one surface by an optical length measuring device and a focal depth of a bottom portion of the funnel portion. In the nozzle plate manufacturing method in any one of Claim 1 to 3,
In the fourth step, a specific area including the nozzle is removed from the other surface. In the nozzle plate manufacturing method in any one of Claim 1 to 4,
The length of the outline shape of the punch corresponding to the same-diameter portion is larger than a predetermined length of the same-diameter portion formed on the plate. A method of manufacturing a droplet discharge head having a nozzle plate,
A method for manufacturing a droplet discharge head, wherein the nozzle plate is manufactured by the nozzle plate manufacturing method according to claim 1. A method of manufacturing a droplet discharge device having a droplet discharge head,
A method for manufacturing a droplet discharge apparatus, wherein the droplet discharge head is manufactured by the method for manufacturing a droplet discharge head according to claim 6.

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