JP2007290237A - Manufacturing method for liquid droplet ejection head and liquid droplet ejection head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently work a flow passage and a pressure chamber in a flow passage plate. <P>SOLUTION: A void part 32 and a hole part 34 are formed inside of a transparent substrate 26 by condensing a laser beam ejected from a laser beam source 28 into the transparent substrate 26. The void part 32 and the hole part 34 are etched and enlarged by an etching liquid by supplying the etching liquid from the hole part 34, whereby the pressure chamber and the passage are formed. The void part 32 and the hole part 34 in which the etching liquid flows are formed inside of the transparent substrate 26 by the laser beam, and the void part 32 and the hole part 34 are enlarged by etching. The pressure chamber, a diaphragm and the passage are thereby worked in the transparent substrate 26 without decreasing the working efficiency. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a droplet discharge head that discharges droplets from a nozzle, and a droplet discharge head manufactured by the manufacturing method.

  In the case of a piezoelectric ink jet recording head, high temperature processing is performed in the step of forming the piezoelectric element, and therefore, the material constituting the ink jet recording head is required to have high temperature heat resistance (500 ° C. or higher).

  However, when an inkjet recording head is configured by laminating a plurality of plates, warpage may occur in each plate due to a difference in linear expansion. As a result, a gap may be generated between the plates, or a deviation may occur between the plates, and the inkjet recording head may not be manufactured with high accuracy.

  In view of this, there is one that prevents the warpage of the plate during high temperature processing by forming a pressure chamber and an ink flow path in a single thick plate. For example, there is a method of forming a desired shape (flow path or the like) inside a plate by irradiating a femtosecond laser from the outside of the plate using a plate made of a transparent member having a predetermined thickness (Patent Document 1). reference).

  However, since the beam condensing spot diameter of the femtosecond laser is as small as about 2 to 4 μm, there is a problem that it is difficult to obtain sufficient processing energy and the processing efficiency is poor.

In addition, a method of processing a flow path or the like inside the plate by wet etching is also conceivable, but since etching proceeds isotropic according to the crystal structure of the material constituting the plate, a complicated shape cannot be created, that is, There is a problem that a desired flow path shape cannot be obtained.
JP 2001-198684 A

  In view of the above problems, an object of the present invention is to efficiently process a flow path and a pressure chamber in a flow path plate.

  According to the first aspect of the present invention, there is provided a liquid flow path that communicates with the nozzle, a pressure chamber that communicates with the flow path and is filled with the liquid, constitutes a part of the pressure chamber, and is displaced to form the pressure chamber. In a method for manufacturing a droplet discharge head comprising a flow path plate made of a transparent member having a vibration plate that applies pressure to the liquid, a laser beam emitted from a light source is condensed inside the flow path plate. Forming a cavity inside the flow path plate and forming a communication hole for communicating the cavity and the outside of the flow path plate; and supplying an etchant from the communication hole, And a step of expanding the communication hole by etching to form the pressure chamber, the diaphragm, and the flow path.

  According to the first aspect of the present invention, the laser light emitted from the light source is condensed inside the flow path plate, and the communication hole that communicates the cavity and the outside of the flow path plate is provided as the flow path plate. Form inside. Then, by supplying the etching solution from the communication hole, the cavity and the communication hole are etched and enlarged by the etching solution, and a pressure chamber, a diaphragm, and a flow path are formed.

  In this manner, by forming a cavity into which the etching solution flows into the flow path plate by the laser light and enlarging the cavity by etching, it is possible to efficiently form a pressure chamber, a diaphragm and a flow path having desired shapes. That is, the pressure chamber, the diaphragm, and the flow path can be formed in a short time compared with the case of processing with only laser light.

  According to a second aspect of the present invention, the plurality of the cavities and the communication holes are formed, and the plurality of the cavities and the communication holes are expanded and communicated by etching, and the pressure chamber, the diaphragm, and the flow path It is characterized by forming.

  In the invention described in claim 2, a plurality of cavities and communication holes are formed in the flow path plate by laser light. Then, an etching solution is supplied from each communication hole to each cavity, and by expanding each communication hole and cavity, a plurality of communication holes communicate with each other to form a flow path, and a plurality of cavities communicate with each other. A pressure chamber and a diaphragm are formed.

  Thus, even when the width of the pressure chamber and the flow path is wide, after forming a plurality of cavities and communication holes with laser light, etching and expanding each of the cavities and communication holes, only the laser light Compared with the case of processing by the method, the pressure chamber, the diaphragm and the flow path can be formed in a short time.

  The present invention according to claim 3 is characterized in that the light source uses a YAG laser.

  In the invention according to the third aspect, the flow path plate can be efficiently processed by using a YAG laser having a beam spot larger than that of the femtosecond laser and lower energy loss.

  The present invention according to claim 4 is characterized in that the etching solution supplied to the cavity from the communication hole is vibrated with ultrasonic waves.

  In the invention described in claim 4, ultrasonic waves are applied to the etching solution supplied to the cavity from the communication hole. As a result, the etchant is stirred, and the dissolved material in the flow path plate that is etched and stays in the communication hole and the cavity is easily discharged out of the flow path plate.

  According to a fifth aspect of the present invention, there is provided a liquid flow path communicating with the nozzle, a pressure chamber communicating with the flow path and filled with liquid, and constituting a part of the pressure chamber so as to be displaced. In a method of manufacturing a droplet discharge head including a flow path plate made of a transparent member having a vibration plate that applies pressure to the liquid, a step of joining a piezoelectric element after forming an electrode on the upper surface of the flow path plate And irradiating the lower surface of the flow path plate with laser light and condensing it inside the flow path plate, forming a cavity inside the flow path plate, and connecting the cavity and the outside of the flow path plate A step of forming a communication hole for communication; a step of forming a protective layer on the upper surface of the flow path plate and the piezoelectric element; and an etching solution is supplied from the communication hole to etch the cavity and the communication hole. Expand the pressure chamber, Rotation plate, and is characterized by having the steps of forming the flow path.

  In the fifth aspect of the present invention, an electrode is formed on the upper surface of the flow path plate, the piezoelectric element is bonded, and then a laser beam is applied to the lower surface of the flow path plate to thereby form the cavity and the outside of the flow path plate. Are formed in the flow path plate. Then, a protective layer is formed on the upper surface of the flow path plate and the piezoelectric element, an etching solution is supplied from each communication hole to each cavity, the communication hole and the cavity are enlarged, and the pressure chamber, the vibration plate, and the flow path are formed. Form.

  Thus, before forming the cavity and the communication hole in the flow path plate, the piezoelectric element is bonded to the upper surface of the flow path plate, so that the cavity can be formed with the piezoelectric element as a mark.

  In addition, when the etching solution is supplied from the communication hole to the cavity, the piezoelectric element is protected by the protective layer, so that the piezoelectric device is not damaged by the etching solution.

  The present invention described in claim 6 is characterized by being manufactured by the method for manufacturing a droplet discharge head according to any one of claims 1 to 5.

  In the invention described in claim 6, a cavity and a communication hole are formed in the flow path plate by laser light, and the pressure chamber, the vibration plate, and the flow path are formed in the flow path plate by enlarging the flow path plate to a desired shape. Thus, the droplet discharge head can be manufactured efficiently.

  Since the present invention has the above-described configuration, the flow path and the pressure chamber can be efficiently processed in the flow path plate.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. First, a schematic configuration of the ink jet recording head 10 will be described with reference to FIG.

  As shown in FIG. 1, the ink jet recording head 10 has a nozzle plate 12. The nozzle plate 12 is formed with nozzles 14 for ejecting ink droplets.

  A flow path plate 16 having a predetermined thickness is stacked on the nozzle plate 12. A pressure chamber 18 having a rectangular cross section is formed in the flow path plate 16, and the pressure chamber 18 is filled with ink from an ink supply hole (not shown) formed in the top plate of the flow path plate 16. It has become so.

  A flow path 20 is formed in the flow path plate 16 from the vicinity of the left end of the pressure chamber 18 to the lower surface. That is, the flow path 20 is formed so as to penetrate the lower surface of the flow path plate 16, and one end of the flow path 20 communicates with the nozzle 14 of the nozzle plate 12 provided under the flow path plate 16. . As a result, the ink filled in the pressure chamber 18 is supplied to the nozzle 14 via the flow path 20, and ink droplets are ejected from the nozzle 14.

  On the other hand, a piezoelectric element 22 as pressure generating means is attached to the upper part of the flow path plate 16 at a position corresponding to the pressure chamber 18. The piezoelectric element 22 is configured such that a driving voltage is applied from a flexible wiring substrate (not shown), and is deformed by the applied voltage to vibrate the diaphragm 16A forming a part of the pressure chamber 18. Thus, the pressure chamber 18 is expanded and contracted, and the ink filled in the pressure chamber 18 is ejected from the nozzle 14.

  Next, a method for manufacturing the inkjet recording head 10 will be described.

  First, the pressure chamber 18, the diaphragm 16A, and the channel 20 are formed in the channel plate 16 having a predetermined thickness, and the electrode layer 17 is formed on the upper surface of the diaphragm 16A. A method for forming the pressure chamber 18, the diaphragm 16A, and the flow path 20 will be described later.

  On the other hand, an electrode layer 23 is formed on the upper surface of a plate-like piezoelectric body processed to a predetermined thickness, thereby forming the piezoelectric element 22. Then, the piezoelectric element 22 is bonded to the position corresponding to the pressure chamber 18 on the electrode layer 17 formed on the upper surface of the flow path plate 16 by bonding or the like.

  Next, a flexible wiring board (not shown) is soldered on the electrode layer 23 of the piezoelectric element 22. Further, the nozzle plate 12 is joined to the lower surface of the flow path plate 16. A flow path 19 for supplying ink supplied from an ink pool (not shown) to the pressure chamber 18 is formed on the upper surface of the vibration plate 16A. The inkjet recording head 10 is created by the above method.

  Here, a method of forming the pressure chamber 18, the vibration plate 16A, and the flow path 20 in the flow path plate 16 will be described with reference to FIG.

  A transparent substrate 26 made of synthetic quartz is placed on the processing table 24, and a laser beam with a beam spot diameter reduced to Φ20 mm is irradiated from a laser light source 28. A galvanometer mirror 30 is disposed downstream of the laser light source 28 (downstream of the laser beam emission direction). The galvanometer mirror 30 includes a reflecting mirror surface that reflects and collects laser light emitted from the laser light source 28, and a drive unit that reciprocally rotates the reflecting mirror surface within a certain angle range at a constant speed.

  When the laser beam emitted from the laser light source 28 is condensed inside the transparent substrate 26 by the reflecting mirror surface, and the reflecting mirror surface is shaken by the driving unit, the laser beam is scanned and a desired shape (here) is formed inside the transparent substrate 26. Then, the hole 34 and the cavity 32) to be the pressure chamber 18 and the flow path 20 later are processed.

  As the laser light source 28, a YVO4 laser that emits a YAG fourth harmonic laser beam (wavelength 266 nm, output 300 mW) is used. That is, by using a YAG fourth harmonic laser having a beam spot larger than that of the femtosecond laser, energy loss when processing the inside of the transparent substrate 26 can be suppressed to a low level. Can be processed.

  By the above method, the cavity 32 corresponding to the pressure chamber 18 (see FIG. 1) is formed slightly above the center line in the thickness direction along the thickness direction of the transparent substrate 26. A hole 34 corresponding to the flow path 20 (see FIG. 1) is processed at one end in the longitudinal direction of the cavity 32 so as to be orthogonal to the cavity 32. The hole 34 penetrates the lower surface of the transparent substrate 26, and the cavity 32 communicates with the outside air through the hole 34.

  Next, as shown in FIG. 3, the upper and lower surfaces of the transparent substrate 26 are protected by a resist 36 except for the hole 34.

  Then, the transparent substrate 26 is immersed in an etching solution (for example, a 15% hydrofluoric acid solution) stored in the bathtub 38. At this time, the end of the bottom surface of the transparent substrate 26 is supported by the support base 40 placed on the bottom surface of the bathtub 38, and a gap is formed between the bottom surface of the bathtub 38 and the bottom surface of the transparent substrate 26. . Then, the etching solution in the gap enters the cavity 32 from the hole 34.

  And an ultrasonic wave is applied with the ultrasonic transmitter 27 attached to the side wall of the bathtub 38, and the etching solution stored in the bathtub 38 is vibrated. As a result, the etching solution that has entered the hole 34 and the cavity 32 is stirred, and the dissolved solution of the transparent substrate 26 that is etched and stays in the hole 34 and the cavity 32 is smoothly removed from the transparent substrate 26. Is discharged.

  As described above, the hole 34 and the cavity 32 are isotropically etched to form the flow path 20 and the pressure chamber 18, respectively. Further, by forming the pressure chamber 18, the ceiling portion of the pressure chamber 18 becomes the diaphragm 16A.

  Thus, the hole 34 and the cavity 32 into which the etching solution flows into the transparent substrate 26 are formed by the laser beam (here, the YAG fourth harmonic laser beam), and the hole 34 and the cavity 32 are enlarged by etching. Thus, the pressure chamber 18, the diaphragm 16A, and the flow path 20 can be formed in the transparent substrate 26 without reducing the processing efficiency.

  In the present embodiment, the configuration has been described in which the cavity 32 and the hole 34 are processed inside the transparent substrate 26 by rotating the reflecting mirror surface of the galvanometer mirror 30, but the galvanometer mirror 30 is fixed to the transparent substrate 26. The cavity 32 and the hole 34 may be processed inside the transparent substrate 26 while moving the processing table 24 on which the substrate 26 is placed.

  Next, a second embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIG. 4 (A), a transparent substrate 42 made of synthetic quartz is irradiated with a YAG quadruple wave laser, and 50 to 50 along the thickness direction of the transparent substrate 42 and slightly above the center line in the thickness direction. A plurality of (seven in this embodiment) cavities 44 are formed at intervals of 200 μm. Then, the hole 46 is processed at one end in the longitudinal direction of each cavity 44 so as to be orthogonal to the cavity 44. The hole 46 penetrates the lower surface of the transparent substrate 42, and the air is communicated with each cavity 44 through each hole 46.

  Next, although not shown, the upper and lower surfaces of the transparent substrate 42 are protected and immersed in an etching solution (for example, a 15% hydrofluoric acid solution). As a result, the etchant enters the cavity 44 from each hole 46, and the hole 46 and the cavity 44 are isotropically etched. Then, each hole 46 and the cavity 44 are enlarged, and the adjacent holes 46 and the cavity 44 communicate with each other to form a flow path 48 and a pressure chamber 50 as shown in FIG. 4B. The

  As described above, even when the width of the pressure chamber 50 and the flow path 48 is wide, after the plurality of cavities 44 and the holes 46 are formed by the YAG quadruple laser, the respective cavities 44 and the holes 46 are formed by etching. By etching and enlarging, the pressure chamber 50, the vibration plate 42A, and the flow path 48 can be formed in a short time compared with the case of processing with only laser light.

  Next, a third embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIG. 5, the electrode layer 54 is formed on the upper surface of the transparent substrate 52 made of synthetic quartz, and the other surface of the piezoelectric element 58 having the electrode layer 56 formed on one surface is formed on the transparent substrate. It is stacked on the electrode layer 54 of 52. Then, a YAG fourth harmonic laser is irradiated to the lower side of the transparent substrate 52 to process the cavity 60 inside the transparent substrate 52 and the hole 70 that communicates the cavity 60 with the outside.

  Next, as shown in FIG. 6, the electrode layer 54 and the piezoelectric element 58 formed on the transparent substrate 52 are protected by a resist 62. Further, the lower surface of the transparent substrate 52 is also protected by a resist 64.

  Then, the transparent substrate 52 whose upper and lower surfaces are protected by the resists 62 and 64 is immersed in an etching solution (for example, a 15% hydrofluoric acid solution) stored in the bath 38. As a result, the etchant enters the hole 70 and the cavity 60, and the hole 70 and the cavity 60 are isotropically etched by the etchant to form the flow channel 66 and the pressure chamber 68.

  In this way, first, the piezoelectric element 58 is bonded to the upper surface of the transparent substrate 52, and in the subsequent process, the cavity 60 is processed inside the transparent substrate 52 with a YAG quadruple wave laser so that the piezoelectric element 58 serves as a mark. The cavity 60 can be formed.

  Further, since the piezoelectric element 58 is protected by the resist 62, the piezoelectric element 58 is not damaged even if the transparent substrate 52 is immersed in an etching solution.

1 is a schematic configuration diagram of an ink jet recording head according to a first embodiment of the present invention. It is a side view which shows the process of manufacturing a pressure chamber and a communicating hole in the board | substrate mounted in the inkjet recording head which concerns on the 1st Embodiment of this invention. It is a side view which shows the process of manufacturing a pressure chamber and a communicating hole in the board | substrate mounted in the inkjet recording head which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the process of manufacturing a pressure chamber and a communicating hole in the board | substrate mounted in the inkjet recording head which concerns on the 2nd Embodiment of this invention. It is a side view which shows the process of manufacturing a pressure chamber and a communicating hole in the board | substrate mounted in the inkjet recording head which concerns on the 3rd Embodiment of this invention. It is a side view which shows the process of manufacturing a pressure chamber and a communicating hole in the board | substrate mounted in the inkjet recording head which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

10 Inkjet recording head (droplet ejection head)
16 channel plate 16A diaphragm 18 pressure chamber 20 channel 26 transparent substrate (channel plate)
28 Laser light source
30 Galvano mirror (lens)
32 Cavity (Cavity)
34 hole (communication hole)
42 Transparent substrate (channel plate)
44 Cavity (Cavity)
46 hole (communication hole)
48 communication hole (flow path)
50 Pressure chamber 52 Transparent substrate (channel plate)
60 Cavity (Cavity)
66 Communication hole (flow path)
68 Pressure chamber 70 Hole (communication hole)

Claims (6)

A liquid flow path communicating with the nozzle, a pressure chamber communicating with the flow path and filled with the liquid, a vibration plate that constitutes a part of the pressure chamber and displaces and applies pressure to the liquid in the pressure chamber; In a manufacturing method of a droplet discharge head provided with a flow path plate made of a transparent member having
A laser beam emitted from a light source is condensed inside the flow path plate to form a cavity inside the flow path plate, and a communication hole that connects the cavity and the outside of the flow path plate is formed. And a process of
Supplying an etchant from the communication hole, expanding the cavity and the communication hole by etching, and forming the pressure chamber, the diaphragm, and the flow path;
A method of manufacturing a droplet discharge head, comprising:   The plurality of the cavities and the communication holes are formed, and the plurality of the cavities and the communication holes are expanded and communicated by etching to form the pressure chamber, the diaphragm, and the flow path. 2. A method for manufacturing a droplet discharge head according to 1.   The method for manufacturing a droplet discharge head according to claim 1, wherein a YAG laser is used as the light source.   4. The method of manufacturing a droplet discharge head according to claim 1, wherein the etching solution supplied to the cavity from the communication hole is vibrated with ultrasonic waves. 5. A liquid flow path communicating with the nozzle, a pressure chamber communicating with the flow path and filled with the liquid, a vibration plate that constitutes a part of the pressure chamber and displaces and applies pressure to the liquid in the pressure chamber; In a manufacturing method of a droplet discharge head provided with a flow path plate made of a transparent member having
Forming an electrode on the upper surface of the flow path plate and then bonding the piezoelectric element;
The lower surface of the flow path plate is irradiated with laser light to be condensed inside the flow path plate, forming a cavity inside the flow path plate, and communicating the cavity with the outside of the flow path plate. Forming a communication hole;
Forming a protective layer on the upper surface of the flow path plate and the piezoelectric element;
Supplying an etchant from the communication hole, expanding the cavity and the communication hole by etching, and forming the pressure chamber, the diaphragm, and the flow path;
A method of manufacturing a droplet discharge head, comprising:   A droplet discharge head manufactured by the method for manufacturing a droplet discharge head according to claim 1.

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