JP2006150349A - Method for manufacturing filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a filter capable of easily manufacturing the filter having both excellent anti-corrosion properties and abrasion resistant properties. <P>SOLUTION: A metal substrate 52 having a plurality of holes 52a is manufactured, a ceramic layer 61 is formed by depositing very small particles of ceramic materials and a filter 43 having a plurality of holes 43a can be obtained on a surface of one side of the substrate 52. Thus, a filter 43 with a thin filter having both excellent anti-corrosion properties and abrasion resistant properties which is made by ceramic materials can easily be manufactured. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a filter for removing dust contained in a fluid.

  A filter having a large number of holes through which a fluid passes is widely used in various fields for the purpose of removing dust contained in the fluid. For example, an inkjet head that ejects ink from a nozzle having a small diameter is provided with a filter having a hole having a diameter smaller than the nozzle diameter in order to prevent the nozzle from being clogged with dust and being unable to eject ink. It is common (for example, refer patent document 1). The filter of the inkjet head of Patent Document 1 is formed by electroforming. That is, after a resist pattern corresponding to a large number of holes is formed on the surface of a conductive substrate, a metal such as nickel or copper is deposited on the portion of the substrate where the resist pattern is not formed by electroplating. A thin metal film is formed, and finally the substrate is removed from the metal film to obtain a filter.

JP 2004-268454 A (FIG. 1)

  However, when the filter is formed by electroforming, the material of the filter is limited to a metal material having low corrosion resistance such as nickel or copper. Therefore, when the filter is provided in a corrosive fluid such as ink, the diameter of the filter hole gradually increases due to the corrosion, and the dust removing function of the filter deteriorates.

  On the other hand, it is possible to form the filter by a method other than electroforming. However, for example, when a hole is formed in a stainless steel substrate having high corrosion resistance by machining such as micro punching or drilling, the substrate has a diameter smaller than the diameter of the nozzle (for example, 10 μm or less). It is difficult to form a large number of holes. In addition, when holes are formed in a base material made of a synthetic resin material by laser processing, it is possible to form a filter having fine holes, but the corrosion resistance and wear resistance of the synthetic resin used as the base material Therefore, the pores of the filter gradually increase due to corrosion and wear by the corrosive fluid.

  The objective of this invention is providing the manufacturing method which can manufacture easily the filter excellent in both corrosion resistance and abrasion resistance.

Means for Solving the Problems and Effects of the Invention

  The present invention is embodied as a filter manufacturing method. The method for producing a filter of the present invention includes a step of producing a metal substrate having a plurality of holes, and a ceramic layer having the plurality of holes by depositing ceramic material particles on one surface of the substrate. Forming a step. In this manufacturing method, a ceramic layer is formed on one surface of the substrate. The base material is provided with a plurality of holes, and the ceramic layer formed by the above method has a plurality of holes as in the base material. And this ceramic layer can be utilized as a filter.

  In general, with the use of a filter, the pores of the filter become larger due to wear when the fluid passes through the holes or due to corrosion by a corrosive fluid, and its dust removing function gradually decreases. However, according to the filter manufacturing method of the present invention, a filter having a ceramic layer having high wear resistance and high corrosion resistance can be manufactured. Therefore, the pores of the filter are not easily reduced due to wear and corrosion, the degree of reduction in the dust removal function is reduced, and the life of the filter is extended. Further, since the filter has high corrosion resistance, the filter can be applied to various devices using various fluids including corrosive fluids, and the use range of the filter is expanded. That is, it is possible to manufacture a long-life filter in which the dust removal function is unlikely to deteriorate.

  In addition, since the ceramic material has high hardness, it is extremely difficult to accurately form a plurality of holes in the ceramic material by machining. However, a ceramic layer having a plurality of holes formed with high accuracy can be obtained by forming a ceramic layer on a substrate having a large number of holes as in the above manufacturing method.

  In the above manufacturing method, the ceramic layer is preferably formed by any one of an aerosol deposition method, a sputtering method, and a chemical vapor deposition method. According to these methods, a ceramic layer can be formed by easily depositing ceramic material particles on one surface of a substrate having a plurality of holes. By simply forming a ceramic layer, it is possible to easily manufacture a filter having holes corresponding to the holes on the substrate side and having excellent wear resistance and corrosion resistance, and simplifying the filter manufacturing process. Manufacturing cost can be reduced. In addition, by using any one of the aerosol deposition method, sputtering method, and chemical vapor deposition method, a very thin ceramic layer can be easily formed. The flow resistance (pressure loss) when passing through the filter can be reduced.

In the above-described filter manufacturing method, the base material manufacturing step includes forming a resist pattern corresponding to the plurality of holes on the substrate, and then electroplating a metal layer on a portion of the substrate where the resist pattern is not formed. After forming the substrate, it is preferable to produce the substrate by peeling the substrate from the metal layer. The shape of the hole of the manufactured filter is determined by the shape of the hole of the base material. Therefore, if the hole of the substrate can be formed with high accuracy, the hole of the manufactured filter can also be formed with high accuracy. According to this base material production process, a base material having a plurality of holes with small diameters can be easily formed with high accuracy, and as a result, the accuracy of the hole shape of the manufactured filter can be ensured.

Alternatively, the above-described filter manufacturing method preferably includes a step of depositing ceramic material particles on the other surface of the base material and further forming a ceramic layer in the ceramic layer forming step. Since the entire metal substrate having high strength is coated with a ceramic layer having high wear resistance and corrosion resistance, a filter having both excellent wear resistance and corrosion resistance and high strength can be produced.

  The above-described filter manufacturing method preferably includes a base material removing step of removing the base material from the ceramic layer after the ceramic layer forming step. Thus, by removing the substrate from the ceramic layer, the thickness of the entire filter can be further reduced, and the flow resistance (pressure loss) of the fluid caused by the filter can be further reduced.

  In the manufacturing method described above, in the step of removing the base material from the ceramic layer, it is preferable that only the central portion of the base material is removed from the ceramic layer and the peripheral portion of the base material is not removed from the ceramic layer. By leaving the peripheral portion of the substrate in the ceramic layer, a filter in which the periphery of the ceramic layer is reinforced with a highly rigid metallic frame can be obtained. Since the periphery is reinforced with a highly rigid metal frame, such a filter is not easily damaged and can be easily handled during assembly.

  Furthermore, in the above-described manufacturing method, the step of removing the base material from the ceramic layer includes the step of forming a mask corresponding to the peripheral portion on the other surface of the base material, and the step of removing the central portion of the first substrate by etching. And removing from the layer. By adopting such a method, only the central part of the substrate can be easily removed from the ceramic layer.

  Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. This embodiment is an example in which the present invention is applied to a filter of an inkjet head that ejects ink onto a recording sheet.

  First, the ink jet printer 100 including the ink jet head 1 will be briefly described. As shown in FIG. 1, an inkjet printer 100 includes a carriage 101 that can move in the left-right direction (= scanning direction) in FIG. 1 and a serial type that is provided on the carriage 101 and ejects ink onto recording paper P. The inkjet head 1 and the conveyance roller 102 etc. which convey the recording paper P to the front (= paper feeding method) of FIG. 1 are provided. The ink jet head 1 moves in the scanning direction integrally with the carriage 101, and applies ink to the recording paper P from the emission port of the nozzle 20 (see FIGS. 2 to 4) formed on the ink ejection surface on the lower surface thereof. Spray. Then, the recording paper P recorded by the inkjet head 1 is discharged in the paper feeding direction by the transport roller 102.

  Next, the inkjet head 1 will be described with reference to FIGS.

As shown in FIGS. 2 to 4, the inkjet head 1 includes an individual ink including a pressure connection 14 and a cylindrical connection member 42 connected via an ink tank (not shown) and an ink supply tube (not shown). A flow path 21 (see FIG. 4) includes a flow path unit 2 formed therein, and a piezoelectric actuator 3 stacked on the upper surface of the flow path unit 2. The ink supplied from the connection member 42 is ejected from a plurality of nozzles 20 provided in the lower part of the flow path unit 2.

First, the flow path unit 2 will be described. As shown in FIGS. 3 and 4, the flow path unit 2 includes a cavity plate 10, a base plate 11, a manifold plate 12, and a nozzle plate 13, and these four plates 10 to 13 are stacked in order from the top. It is glued. In addition, the piezoelectric actuator 3 includes a vibration plate 30, and the vibration plate 30 is laminated and joined to the upper part of the cavity unit 10 of the flow path unit 2.

  As shown in FIGS. 2 and 3, the cavity plate 10 is formed with a plurality of pressure chambers 14 arranged along a plane, and these pressure chambers 14 are arranged on the diaphragm 30 side (see FIG. (Above 4). Each pressure chamber 14 is formed in a substantially elliptical shape that is long in the scanning direction (left-right direction in FIG. 2) in plan view.

  As shown in FIGS. 3 and 4, communication holes 15 and 16 are formed at positions overlapping the both ends in the longitudinal direction of the pressure chamber 14 in plan view of the base plate 11, respectively. Further, the manifold plate 12 is formed with a manifold 17 that extends in the paper feeding direction (vertical direction in FIG. 2) and overlaps either one of the right and left ends of the pressure chamber 14 in FIG. A communication hole 19 is formed at a position overlapping the end of the pressure chamber 14 opposite to the manifold 17 in plan view. Further, the nozzle plate 13 is formed with a plurality of nozzles 20 at positions overlapping with the plurality of communication holes 19 in plan view.

  As shown in FIG. 3, communication holes 40 and 41 communicating with the manifold 17 are formed in the cavity plate 10 and the base plate 11. An ink supply port 18 connected to the communication hole 40 is formed in the vibration plate 30 of the piezoelectric actuator 3 joined to the upper surface of the cavity plate 10. Further, a cylindrical connection member to which the above-described ink supply tube (not shown) connected to the ink tank (not shown) is connected to a position corresponding to the ink supply port 18 on the upper surface of the vibration plate 30. 42 is fixed with an adhesive or the like. Ink is supplied to the manifold 17 from the ink tank through the ink supply tube, the connection member 42, the ink supply port 18, and the communication holes 40 and 41.

  A filter 43 made of a ceramic material such as alumina, zirconia, silicon nitride, or silicon carbide and having a very thin thickness (for example, about 5 to 10 μm) is interposed between the diaphragm 30 and the connection member 42. ing. The filter 43 has a large number of holes 43a through which ink passes, and the diameter of the large number of holes 43a is smaller than the diameter (for example, about 20 μm) of the nozzle 20 that ejects ink (for example, about 10 μm). ). Therefore, the dust contained in the ink supplied from the ink tank to the manifold 17 is surely removed by the filter 43, so that it is possible to prevent the dust from being clogged and becoming unable to eject ink from the nozzle 20. Here, as the ink jet head 1 is used, the hole 43a becomes larger due to wear when the ink passes through the hole 43a or corrosion due to the ink, and the dust removing function of the filter 43 gradually decreases. . However, the filter 43 is made of a ceramic material having high wear resistance and corrosion resistance. Therefore, since the hole 43a is not easily increased due to wear or corrosion, the degree of decrease in the dust removal function is reduced, and the life of the filter 43 is extended. A method for manufacturing the filter 43 will be described in detail later.

  As shown in FIG. 4, the manifold 17 communicates with the pressure chamber 14 through the communication hole 15, and the pressure chamber 14 communicates with the nozzle 20 through the communication holes 16 and 19. In this way, the individual ink flow path 21 extending from the manifold 17 to the nozzle 20 through the pressure chamber 14 is formed in the flow path unit 2.

  Next, the piezoelectric actuator 3 will be described. As shown in FIGS. 3 and 4, the piezoelectric actuator 3 includes a metal vibration plate 30 disposed on the upper surface of the flow path unit 2, a piezoelectric layer 31 formed on the upper surface of the vibration plate 30, and the piezoelectric actuator 3. A plurality of individual electrodes 32 formed respectively corresponding to the plurality of pressure chambers 14 are provided on the upper surface of the layer 31.

  The diaphragm 30 is laminated and joined to the upper surface of the cavity plate 10 so as to cover the plurality of pressure chambers 14. The diaphragm 30 also serves as a common electrode that opposes the plurality of individual electrodes 32 and applies an electric field to the piezoelectric layer 31 between the individual electrodes 32 and the diaphragm 30, and the diaphragm 30 is grounded. It is held at ground potential. On the upper surface of the vibration plate 30, a piezoelectric layer 31 mainly composed of lead zirconate titanate (PZT), which is a solid solution and is a ferroelectric substance, is formed of lead titanate and lead zirconate.

  On the upper surface of the piezoelectric layer 31, a plurality of individual electrodes 32 having an elliptical planar shape that is slightly smaller than the pressure chamber 14 and made of a conductive material are formed. The plurality of individual electrodes 32 are respectively disposed in regions facing the central portion of the corresponding pressure chamber 14 in plan view. Further, on the upper surface of the piezoelectric layer 31, a plurality of terminal portions 35 extending in the scanning direction from the end portions on the manifold 17 side of the plurality of individual electrodes 32 are also formed. As shown in FIG. 4, the plurality of terminal portions 35 are electrically connected to the driver IC 37 through flexible wiring members (not shown) such as flexible printed wiring boards. A drive voltage is selectively supplied to the plurality of individual electrodes 32 via the unit 35.

  Next, the operation of the piezoelectric actuator 3 will be described.

When a driving voltage is selectively applied to the plurality of individual electrodes 32 from the driver IC 37, the individual electrodes 32 on the upper side of the piezoelectric layer 31 to which the driving voltage is supplied and the lower side of the piezoelectric layer 31 held at the ground potential. The potentials of the diaphragm 30 as the common electrode are in different states, and an electric field in the vertical direction is generated in the portion of the piezoelectric layer 31 sandwiched between the individual electrode 32 and the diaphragm 30. Then, the portion of the piezoelectric layer 31 directly below the individual electrode 32 to which the drive voltage is applied contracts in the horizontal direction orthogonal to the vertical direction that is the polarization direction. At this time, the diaphragm 30 is deformed so as to protrude toward the pressure chamber 14 as the piezoelectric layer 31 contracts, so that the volume in the pressure chamber 14 decreases and pressure is applied to the ink in the pressure chamber 14. Ink droplets are ejected from the nozzle 20 communicating with the pressure chamber 14.

Next, a method for manufacturing the ceramic filter 43 will be described.

  First, the base material 52 having a large number of holes 52a corresponding to the large number of holes 43a of the filter 43 is manufactured (base material manufacturing step). As shown in FIG. 5A, a photoresist pattern 51 corresponding to a large number of holes 52a of the base material 52 is formed on a conductive smooth surface of a substrate 50 made of stainless steel, silicon wafer, or the like. . Next, as shown in FIG. 5B, electroplating is performed on the substrate 50 to deposit a metal such as nickel or copper on the portion of the substrate 50 where the photoresist pattern 51 is not formed. A metal layer 60 to be the base material 52 having 52a is formed. As shown in FIG. 5B, the metal such as nickel or copper forming the metal layer 60 is deposited in a slightly rounded shape in the portion where the resist pattern 51 is not formed. Then, as shown in FIG. 5C, the substrate 50 and the resist pattern 51 are peeled from the metal layer 60 to obtain a base material 52 having a large number of holes 52a. In addition, by using a resist pattern and electroplating in this way, it is possible to easily produce a metal substrate 52 having a hole 52a having a very small diameter (for example, about 10 μm).

  Next, as shown in FIG. 5 (d), alumina, zirconia, silicon nitride, or silicon carbide is applied to the smooth surface (the lower surface of FIG. 5 (d)) of the base material 52 attached to the substrate 50. A very thin ceramic layer 61 (for example, about 5 to 10 μm) that becomes the filter 43 is formed by depositing particles of a ceramic material such as (ceramic layer forming step). Here, a ceramic layer 61 is formed by an aerosol deposition method (AD method) in which particles of a very small ceramic material are mixed with a carrier gas and sprayed onto the base material 52 to be collided at high speed and deposited on the base material 52. can do. Alternatively, the ceramic layer 61 may be formed using a sputtering method or a chemical vapor deposition method (CVD method). When the ceramic material particles are deposited on the base material 52, the ceramic layer 61 is not formed at the position where the numerous holes 52a of the base material 52 are formed. Therefore, when the ceramic layer 61 is formed on the base material 52, simultaneously, a hole 43a corresponding to the hole 52a on the base material 52 side is formed in the ceramic layer 61.

  Finally, as shown in FIG. 5E, the metal substrate 52 is removed from the ceramic layer 61 by etching using hydrochloric acid or the like (substrate removal step), and the ceramic filter 43 is obtained.

  According to the manufacturing method of this filter 43, the filter 43 which consists of ceramic material and is excellent in both abrasion resistance and corrosion resistance is obtained. Therefore, the hole 43a of the filter 43 is not easily increased due to wear and corrosion, and the degree of decrease in the dust removal function of the filter 43 is reduced, so that the life of the filter 43 is extended. Further, the filter 43 having a large number of holes 43a having a diameter smaller than the diameter of the nozzle 20 and excellent in both wear resistance and corrosion resistance can be easily manufactured, and the manufacturing cost can be reduced.

  Moreover, the ceramic layer 61 having a large number of holes 43a can be easily formed by forming the ceramic layer 61 by the AD method, the sputtering method, or the CVD method. Since the ceramic material has high hardness, it is extremely difficult to form a hole 43a by subjecting a ceramic material plate to machining such as drilling. However, the smoothness of the metal base 52 having a large number of holes 52a is difficult. It is possible to easily form even the ceramic layer 61 having a large number of holes 43a by forming the ceramic layer 61 by a method of laminating particles (molecules) of ceramic material such as AD method on the surface. become.

  In addition, a very thin ceramic layer 61 can be easily formed on the substrate 52 by using an AD method, a sputtering method, or a CVD method. Furthermore, the overall thickness of the filter 43 can be further reduced by removing the base material 52 from the ceramic layer 61 after forming the ceramic layer 61 on the base material 52. In this way, by reducing the thickness of the filter 43, the flow resistance (pressure loss) when ink passes through the filter 43 can be minimized. In particular, when bubbles that adversely affect the ink ejection operation are mixed in the individual ink flow path 21 including the pressure chamber 14 (see FIG. 4), the ink is forcibly pressurized and discharged from the nozzle 20 together with the bubbles. In other words, a so-called purge operation needs to be performed. However, if the pressure loss of the ink in the filter 43 is small, the speed of the ink discharged from the nozzle 20 increases correspondingly, and bubbles are easily discharged.

Next, modified embodiments in which various modifications are made to the embodiment will be described. However, components having the same configuration as in the above embodiment are given the same reference numerals and description thereof is omitted as appropriate.
(Modification 1)
In the first embodiment, after the ceramic layer 61 is formed using the substrate 52 (metal layer 60), the entire substrate 52 is removed from the ceramic layer 61. At this time, the peripheral portion of the substrate 52 is removed. May be left as it is, and only the central portion of the substrate 52 may be removed. Specifically, as shown in FIG. 5 (d), after the ceramic layer 61 is formed on the smooth surface (lower surface) of the base 52, the other of the base 52 is shown in FIG. 7 (a). A mask 72 is formed on the surface (upper surface). Next, as shown in FIG. 7B, the base material 52 is etched. The central portion of the base material 52 where the mask 72 is not formed is removed from the ceramic layer 61. In this case, it is possible to obtain the filter 73 whose peripheral portion is reinforced with a highly rigid metal frame. The filter 73 is not easily damaged and is easy to handle when assembled to the inkjet head 1. In addition, after removing the center part of the base material 52 from the ceramic layer 61, as shown in FIG.7 (c), you may remove the mask 72 by washing | cleaning by a chemical | medical agent etc. FIG.
(Modification 2)
In the embodiment, after the ceramic layer 61 is formed on the base material 52, the base material 52 is removed from the ceramic layer 61. However, the step of removing the base material 52 may be omitted. In this case, the thickness of the entire filter is increased by the presence of the base material 52. However, a layer of a ceramic material that is generally low in toughness and easily damaged is reinforced by a base material 52 made of a metal material such as nickel or copper, thereby increasing the strength of the filter.
(Modification 3)
As shown in FIG. 6A, after the ceramic layer 70 is formed on the smooth surface (lower surface) of the substrate 52, a slightly rounded surface (upper surface) and holes are formed as shown in FIG. 6B. The entire substrate 52 may be coated with the ceramic layer 70 by depositing a ceramic material on the inner surface of the 52a. In this case, since the entire metal base 52 having high strength is coated with the ceramic layer 70 having high wear resistance and high corrosion resistance, the filter 43A having both excellent wear resistance and corrosion resistance and high strength. Can be obtained.
(Modification 4)
The above embodiment is an example in which the present invention is applied to a filter of an inkjet head. However, since the filter of the present invention has high corrosion resistance, various fluids including corrosive fluids other than ink (only liquids such as water are used). In addition, the filter can be applied to various apparatuses using a gas (such as air).

1 is a schematic perspective view of an ink jet printer according to an embodiment of the present invention. It is a top view of an inkjet head. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is a figure which shows the manufacturing process of a filter, (a) is a resist pattern formation process, (b) is an electroplating process, (c) is a board | substrate peeling process, (d) is a ceramic layer formation process, (e) is a base material The removal process is shown respectively. It is a figure which shows a part of manufacturing process of the filter of a modified form, (a) forms the ceramic layer in one surface of a base material, (b) forms a ceramic layer in the other surface of a base material. Each process is shown. It is a figure which shows a part of manufacturing process of the filter of another modification, (a) shows the process of forming a mask, (b) shows the process of performing an etching, (c) shows the process of removing a mask, respectively.

Explanation of symbols

43, 43A Filter 43a Hole 50 Substrate 51 Resist pattern 52 Base 52a Hole 60 Metal layer 61 Ceramic layer 70 Ceramic layer

Claims (7)

A base material production step for producing a metal base material having a plurality of holes;
A ceramic layer forming step of depositing ceramic material particles on one surface of the base material to form a ceramic layer having the plurality of holes;
A method for manufacturing a filter, comprising:   The method for manufacturing a filter according to claim 1, wherein the ceramic layer is formed by any one of an aerosol deposition method, a sputtering method, and a chemical vapor deposition method.   In the base material manufacturing step, after forming a resist pattern corresponding to the plurality of holes on the substrate, and forming a metal layer on the portion of the substrate where the resist pattern is not formed by electroplating, the metal layer The method for producing a filter according to claim 1, wherein the base material is prepared by peeling the substrate from the substrate.   In the ceramic layer forming step, a ceramic material particle is deposited on the other surface of the base material to further form a ceramic layer, and the whole base material is coated with the ceramic layer. The manufacturing method of the filter in any one of Claims 1-3 to do.   The method for manufacturing a filter according to any one of claims 1 to 3, further comprising a substrate removing step of removing the substrate from the ceramic layer after the ceramic layer forming step.   6. The method for producing a filter according to claim 5, wherein, in the step of removing the base material from the ceramic layer, only a central portion of the base material is removed from the ceramic layer, and a peripheral portion of the base material is not removed from the ceramic layer. . The step of removing the base material from the ceramic layer includes a step of forming a mask corresponding to the peripheral portion on the other surface of the base material, and a step of removing the central portion of the first substrate from the ceramic layer by etching. The filter manufacturing method according to claim 6, further comprising:

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