Flow path forming member, liquid jet head, liquid jet device, method for manufacturing flow path forming member, and method for manufacturing liquid jet head

Abstract

To provide a flow channel formation member, a liquid jet head, a liquid jet device, a method for manufacturing a flow channel formation member, and a method for manufacturing a liquid jet head, which can improve liquid resistance.SOLUTION: A flow channel formation member includes: flow channel formation member bodies 140 and 146 which are formed of a resin material and define at least a part of a flow channel; a metal protective film 200 which is provided on at least a surface defining the flow channel of the flow channel formation member bodies 140 and 146, and is formed of a metal material; and a protective film 210 which is stacked on the metal protective film 200, and contains an oxide or a nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W) and yttrium (Y).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a flow path forming member having a flow path formed therein, a liquid jet head having the flow path forming member, a liquid jet apparatus including the liquid jet head, a method for manufacturing the flow path forming member, and a method for manufacturing the liquid jet head. [Background technology]

[0002] An inkjet recording head, which is an example of a liquid jet head, has a piezoelectric actuator on one side of a flow path forming substrate in which pressure chambers communicating with nozzles are provided, and the piezoelectric actuator is driven to deform a vibration plate, causing a pressure change in the ink in the pressure chambers, thereby ejecting ink droplets from the nozzles.Inkjet recording heads also have flow path forming members made of a resin material that define the flow paths (see, for example, Patent Document 1).

[0003] In such ink jet recording heads, a protective film that is resistant to liquids is provided on the inner walls of the flow paths of the pressure chambers and the like in order to prevent the flow path forming substrate from being eroded by ink. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-124887 Summary of the Invention [Problem to be solved by the invention]

[0005] However, flow path forming members made of resin materials have low resistance to liquids containing acids, bases, or organic solvents, and are prone to erosion and swelling by the liquid.

[0006] For this reason, it is necessary to provide a protective film with high liquid resistance on the inner surface of the flow path of the flow path forming member, but there are problems such as pinholes occurring in the protective film depending on the film formation method, or the protective film being included in the resin material and falling off together with particles that are not resin material, so-called fillers, making it difficult to protect the flow path forming member from liquid.

[0007] It should be noted that such problems are not limited to liquid jet heads such as ink jet recording heads, but also exist in flow path forming members used in other devices. [Means for solving the problem]

[0008] An aspect of the present invention that solves the above-mentioned problems is a flow path forming member comprising: a flow path forming member main body formed of a resin material and defining at least a portion of a flow path; a metal protective film formed of a metal material and provided on at least the surface of the flow path forming member main body that defines the flow path; and a protective film laminated on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y).

[0009] Another aspect of the present invention is a liquid-jet head comprising the flow path forming member described above.

[0010] Another aspect of the present invention is a liquid ejecting apparatus comprising the liquid ejecting head described above.

[0011] Another aspect of the present invention is a method for manufacturing a flow path forming member, which comprises forming a metal protective film of a metal material on at least a surface defining a flow path of a flow path forming member body formed of a resin material and defining at least a portion of the flow path, and then forming a protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y) on the metal protective film by atomic layer deposition.

[0012] Another aspect of the present invention is a method for manufacturing a liquid-jet head, characterized by comprising the method for manufacturing a flow path forming member described above. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 2 is an exploded perspective view of the recording head according to the first embodiment. [Figure 2] 3 is a plan view of a flow path forming substrate of the recording head according to the first embodiment. FIG. [Figure 3] 1 is a cross-sectional view of a recording head according to a first embodiment. [Figure 4] 2 is an enlarged cross-sectional view of a main part of the recording head according to the first embodiment. FIG. [Figure 5] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 6] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 7] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 8] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 9] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 10] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 11]3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 12] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 13] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 14] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 15] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 16] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 17] 3A to 3C are cross-sectional views illustrating a method for manufacturing the recording head according to the first embodiment. [Figure 18] FIG. 10 is a cross-sectional view of a recording head according to a second embodiment. [Figure 19] FIG. 1 is a diagram illustrating a schematic configuration of a recording apparatus according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below based on embodiments. However, the following description illustrates one aspect of the present invention and can be modified as desired within the scope of the present invention. In each drawing, the same reference numerals indicate the same components, and their description will be omitted as appropriate. In each drawing, X, Y, and Z represent three spatial axes that are orthogonal to each other. In this specification, the directions along these axes are referred to as the X direction, Y direction, and Z direction. In each drawing, the direction indicated by the arrow is referred to as the positive (+) direction, and the direction opposite the arrow is referred to as the negative (-) direction. In addition, the three spatial axes that are not limited to the positive and negative directions will be referred to as the X axis, Y axis, and Z axis.

[0015] (Embodiment 1) Fig. 1 is an exploded perspective view of an ink jet recording head 1, which is an example of a liquid jet head according to a first embodiment of the present invention. Fig. 2 is a plan view of a flow path forming substrate 10 of the ink jet recording head 1, as viewed in the +Z direction. Fig. 3 is a cross-sectional view taken along line AA' in Fig. 2. Fig. 4 is an enlarged view of a main part of Fig. 3.

[0016] As shown in the figure, the inkjet recording head 1 (hereinafter simply referred to as the recording head 1) of this embodiment includes multiple components, such as a flow path forming substrate 10, a communication plate 15, a nozzle plate 20, a protective substrate 30, a case member 40, and a compliance substrate 45, and these multiple components are bonded together using an adhesive or the like. The adhesive is often an epoxy adhesive or a silicone adhesive. In this embodiment, the flow path forming substrate 10, the communication plate 15, the nozzle plate 20, and the protective substrate 30 are formed from silicon substrates, such as single-crystal silicon substrates, as will be described in detail later. Furthermore, the case member 40 and at least a portion of the compliance substrate 45 are formed from a resin material, which is easy to manufacture, has a small Young's modulus, and exhibits excellent compliance suitability.

[0017] In this embodiment, the flow path forming substrate 10 is made of a silicon single crystal substrate. A plurality of nozzles 21, each of which ejects ink of the same color and has a plurality of pressure chambers 12, are arranged in a direction along the X axis in this flow path forming substrate 10. In addition, the flow path forming substrate 10 is provided with a plurality of rows, two rows in this embodiment, in which the pressure chambers 12 are arranged in a direction along the X axis, in a direction along the Y axis.

[0018] Furthermore, a communicating plate 15 is bonded to the surface of the flow path forming substrate 10 on the +Z direction side via an adhesive 220. Furthermore, a nozzle plate 20, which has a plurality of nozzles 21 formed therein and which communicate with each pressure chamber 12, is bonded to the surface of the communicating plate 15 on the +Z direction side via an adhesive 221. The communicating plate 15 is provided with nozzle communicating paths 16 that connect the pressure chambers 12 and the nozzles 21. The communicating plate 15 has an area larger than that of the flow path forming substrate 10, and the nozzle plate 20 has an area smaller than that of the flow path forming substrate 10. By making the area of ​​the nozzle plate 20 relatively small in this way, costs can be reduced. In this embodiment, the surface of the nozzle plate 20 where the nozzles 21 open and from which ink droplets are ejected is referred to as the liquid ejection surface 20a.

[0019] The communication plate 15 is also provided with a first manifold portion 17 and a second manifold portion 18 that constitute a part of a manifold 100 that is a "common liquid chamber" to which a plurality of pressure chambers 12 communicate in common.

[0020] The first manifold portion 17 is provided so as to penetrate the communicating plate 15 in the direction along the Z axis. The second manifold portion 18 is provided so as to open on the liquid ejection surface 20a side of the communicating plate 15 without penetrating the communicating plate 15 in the direction along the Z axis.

[0021] Furthermore, in the communication plate 15, supply communication passages 19 are provided independently for each pressure chamber 12, communicating with one end side of the pressure chamber 12 in the direction along the Y axis. These supply communication passages 19 communicate between the second manifold portion 18 and the pressure chamber 12. That is, in this embodiment, the supply communication passages 19, the pressure chambers 12, and the nozzle communication passages 16 are provided as individual flow paths provided for each nozzle 21.

[0022] The communicating plate 15 is preferably made of a material having a linear expansion coefficient similar to that of the flow path-forming substrate 10. In other words, if the communicating plate 15 is made of a material having a linear expansion coefficient significantly different from that of the flow path-forming substrate 10, the difference in the linear expansion coefficient between the flow path-forming substrate 10 and the communicating plate 15 will cause warping when heated or cooled, resulting in damage such as peeling or cracking due to the warping between the flow path-forming substrate 10 and the communicating plate 15. In this embodiment, by using the same material as the flow path-forming substrate 10, i.e., a silicon single crystal substrate, for the communicating plate 15, it is possible to reduce warping due to heat and suppress peeling and damage.

[0023] In addition, the nozzle plate 20 is formed from a silicon single crystal substrate. This makes it possible to make the linear expansion coefficients of the nozzle plate 20 and the communication plate 15 equivalent, thereby reducing the occurrence of warping due to heating and cooling, and suppressing peeling and breakage.

[0024] Nozzles 21 are formed in the nozzle plate 20, which communicate with each pressure chamber 12 via the nozzle communication passages 16. That is, the nozzles 21 are formed in multiple rows (two rows in this embodiment) along the Y axis, each row being arranged parallel to the X axis. In this embodiment, the surface of the nozzle plate 20 in the +Z direction where the nozzles 21 open is referred to as the liquid ejection surface 20a. That is, ink is ejected from the nozzles 21 in the +Z direction. A liquid-repellent film 24 having liquid repellency is provided on this liquid ejection surface 20a.

[0025] The liquid-repellent film 24 is not particularly limited as long as it has water-repellent properties against ink, and for example, a metal film containing a fluorine-based polymer, or a molecular film of a metal alkoxide having liquid-repellent properties can be used.

[0026] The liquid-repellent film made of a metal film containing a fluorine-based polymer can be formed, for example, by directly applying eutectoid plating to the liquid ejecting surface 20a of the nozzle plate 20.

[0027] Furthermore, when a molecular film of a metal alkoxide is used as the liquid-repellent film, for example, by providing an underlayer made of a plasma-polymerized film (PPSi (Plasma Polymerized Silicone) film) on the nozzle plate 20 side, the adhesion between the molecular film and the nozzle plate 20 can be improved. The underlayer made of a plasma-polymerized film can be formed, for example, by polymerizing silicone with argon plasma gas. Furthermore, the molecular film of a liquid-repellent film can be formed, for example, by forming a molecular film of a metal alkoxide that has liquid repellency and then performing a drying process, an annealing process, or the like to form a liquid-repellent film (SCA (silane coupling agent) film). Incidentally, when a molecular film of a metal alkoxide is used as the liquid-repellent film, even if an underlayer is provided, it can be formed thinner than a liquid-repellent film made of a metal film containing a fluorine-based polymer formed by eutectoid plating. In addition, it has the advantages of being able to improve the liquid repellency and "abrasion resistance" (liquid repellency is not deteriorated even when the liquid ejection surface 20a is wiped when cleaning the liquid ejection surface 20a), and the liquid repellency. Of course, a liquid-repellent film made of a metal film containing a fluorine-based polymer can also be used, although it is inferior in "abrasion resistance" and "liquid repellency."

[0028] A vibration plate 50 and a piezoelectric actuator 300 having a first electrode 60, a piezoelectric layer 70, and a second electrode 80 are sequentially stacked on the surface of the flow path forming substrate 10 on the -Z direction side. That is, on the surface of the flow path forming substrate 10 on the -Z direction side, the vibration plate 50, the first electrode 60, the piezoelectric layer 70, and the second electrode 80 are stacked toward the -Z direction.

[0029] The diaphragm 50 has an elastic film 51 made of silicon oxide provided on the flow path forming substrate 10 side, and an insulating film 52 made of zirconium oxide provided on the elastic film 51. The pressure chambers 12 are formed by anisotropically etching the flow path forming substrate 10 from the surface on the +Z direction side, and the surface of the pressure chambers 12 on the -Z direction side is defined by the elastic film. The diaphragm 50 is not particularly limited to this, and may be made of only the elastic film 51 or only the insulating film 52. The diaphragm 50 may also have other films in addition to the elastic film 51 and the insulating film 52. The material of the diaphragm 50 is not limited to the above.

[0030] A piezoelectric actuator 300 is provided on the -Z direction side of the vibration plate 50. The piezoelectric actuator 300 includes a first electrode 60, a piezoelectric layer 70, and a second electrode 80, which are sequentially stacked from the vibration plate 50 side toward the -Z direction. The first electrode 60, the piezoelectric layer 70, and the second electrode 80 are stacked by film formation and lithography. The piezoelectric actuator 300 serves as a pressure generating means that flexes and deforms the vibration plate 50, causing a pressure change in the ink in the pressure chamber 12. Such a piezoelectric actuator 300 is also referred to as a piezoelectric element, and refers to a portion including the first electrode 60, the piezoelectric layer 70, and the second electrode 80. Furthermore, a portion of the piezoelectric layer 70 where piezoelectric strain occurs when a voltage is applied between the first electrode 60 and the second electrode 80 is referred to as an active portion. In contrast, a portion of the piezoelectric layer 70 where piezoelectric strain does not occur is referred to as an inactive portion. In this embodiment, one active portion is formed for each pressure chamber 12. Of course, two or more active portions may be provided for each pressure chamber 12. Generally, one electrode is configured as an individual electrode for each piezoelectric actuator 300, essentially an independent electrode for each active portion, and the other electrode is configured as a common electrode shared by multiple piezoelectric actuators 300, essentially a plurality of active portions. In this embodiment, the first electrode 60 constitutes an individual electrode, and the second electrode 80 constitutes a common electrode. Of course, the first electrode 60 may constitute a common electrode, and the second electrode 80 may constitute an individual electrode. Furthermore, when the first electrode 60 is configured as a common electrode for multiple piezoelectric actuators 300, for example, one or both of the elastic film 51 and the insulating film 52 may not be provided, and only the first electrode 60 may function as a vibration plate.

[0031] As shown in FIG. 2, the first electrode 60 is separated for each pressure chamber 12 and constitutes an independent individual electrode for each piezoelectric actuator 300 .

[0032] 2 and 3, the piezoelectric layer 70 has a predetermined width along the Y axis and is provided continuously in the direction along the X axis. The piezoelectric layer 70 is also provided with recesses 71 corresponding to the partition walls that separate adjacent pressure chambers 12 in the direction along the X axis. Such a piezoelectric layer 70 is made of a piezoelectric material made of a complex oxide with a perovskite structure represented by the general formula ABO3. Examples of piezoelectric materials used for the piezoelectric layer 70 include lead zirconate titanate.

[0033] As shown in FIGS. 2 and 3 , the second electrode 80 is provided continuously on the surface of the piezoelectric layer 70 on the −Z direction side, which is opposite to the first electrode 60, and constitutes a common electrode shared by multiple piezoelectric actuators 300. The second electrode 80 is provided continuously along the +X direction so that the +Y direction has a predetermined width. The second electrode 80 is also provided on the inner surface of the recess 71, i.e., on the side surface of the recess 71 of the piezoelectric layer 70 and on the insulating film 52 which is the bottom surface of the recess 71. Of course, the second electrode 80 may be provided only on a portion of the inner surface of the recess 71, or may not be provided over the entire inner surface of the recess 71.

[0034] Furthermore, individual lead electrodes 91, which are lead wirings, are drawn out from the first electrodes 60. The individual lead electrodes 91 extend along the Y axis, and a plurality of the individual lead electrodes 91 are arranged in parallel in the +X direction.

[0035] Furthermore, a common lead electrode 92, which is a lead wiring, is drawn out from the second electrode 80. The common lead electrode 92 extends along the Y axis, and is drawn out from both ends of the row of piezoelectric actuators 300 on the X axis toward between the two rows of piezoelectric actuators 300 on the Y axis.

[0036] A protective substrate 30 having approximately the same size as the flow path forming substrate 10 is bonded to the surface of the flow path forming substrate 10 on the -Z direction side via an adhesive 222. The protective substrate 30 has holding portions 31, which are spaces for protecting the piezoelectric actuators 300. The holding portions 31 are independently provided for each row of the piezoelectric actuators 300 arranged side by side in the +Z direction, and two holding portions 31 are formed side by side in the +Y direction. The protective substrate 30 also has a through hole 32 penetrating in the +Z direction between the two holding portions 31 arranged side by side in the +Y direction. Ends of the individual lead electrodes 91 and the common lead electrode 92 drawn from the electrodes of the piezoelectric actuators 300 extend so as to be exposed within the through hole 32. The protective substrate 30 is preferably made of a material having a linear expansion coefficient equivalent to that of the flow path forming substrate 10 to which the protective substrate 30 is bonded. In this embodiment, a silicon single crystal substrate is used.

[0037] 3, a case member 40 is fixed to the -Z direction side of the protective substrate 30. The case member 40 defines a manifold 100, which communicates with the multiple pressure chambers 12, together with the flow path forming substrate 10 and the communicating plate 15. The case member 40 has substantially the same shape as the communicating plate 15 described above in a plan view, and is bonded to the communicating plate 15 with an adhesive 223. The case member 40 and the protective substrate 30 are bonded together with an adhesive 224.

[0038] The case member 40 has a recess 41 that opens to the surface on the +Z direction side and has a depth that allows the flow-channel-forming substrate 10 and the protective substrate 30 to be accommodated therein. The recess 41 has an opening area larger than the surface of the protective substrate 30 that is joined to the flow-channel-forming substrate 10. With the flow-channel-forming substrate 10, the protective substrate 30, and the like accommodated in the recess 41, the opening of the recess 41 facing the nozzle plate 20 is sealed by a communicating plate 15. The case member 40 also has third manifold portions 42, which are grooves that open in the +Z direction, on both outer sides of the recess 41 in the direction along the Y axis, i.e., on both the +Y direction and the −Y direction. The third manifold portion 42 has approximately the same opening area as the opening on the −Z direction side of the first manifold portion 17 provided in the communicating plate 15. By joining the case member 40 to the communicating plate 15, the third manifold portion 42 and the first manifold portion 17 are in communication with each other. The manifold 100 of this embodiment is configured by the third manifold portion 42 provided in this case member 40, and the first manifold portion 17 and second manifold portion 18 provided in the communication plate 15. The manifold 100 is provided continuously over the +X direction in which the pressure chambers 12 are arranged side by side, and the supply communication passages 19 that connect the pressure chambers 12 and the manifold 100 are arranged side by side in the +X direction.

[0039] Furthermore, in the case member 40, an introduction path 44, which is a groove that communicates with the manifolds 100 and supplies ink to each manifold 100, is provided on the −Z direction side of the third manifold portion 42. Furthermore, in the case member 40, a connection port 43 that communicates with the through hole 32 of the protection substrate 30 and through which the wiring substrate 121 is inserted is provided.

[0040] Such a case member 40 has a case member main body 140 formed of a resin material, a metal protective film 200 (described in detail below) provided on the case member main body 140, and a protective film 210 (described in detail below) laminated on the metal protective film 200. Note that the above-mentioned third manifold portion 42 and flow paths such as the introduction path 44 are actually provided in the case member main body 140, and the metal protective film 200 and the protective film 210 are formed on the inner surfaces of the flow paths such as the third manifold portion 42 and the introduction path 44 provided in the case member main body 140.

[0041] Examples of resin materials that form the case member main body 140 include polyphenylene sulfide (PPS) resin, ABS resin, polycarbonate, polyamide resin, phenol resin, epoxy resin, modified polyphenylene ether resin, etc. The case member main body 140 of this embodiment corresponds to a "flow path forming member main body" that is formed from a resin material and defines the flow path.

[0042] The third manifold portion 42 and the introduction path 44, which are flow paths provided in the case member main body 140, are made up of "grooves" and have an aspect ratio of 2 or more. Here, a groove includes a recess or a through-hole that opens to the surface. The aspect ratio is the ratio (L / D) of the hole depth (L) divided by the hole diameter (D). For example, if the opening of the third manifold portion 42 in the +Z direction has a rectangular shape, the opening area (S) = πr 2 The radius (r) is calculated from the above formula, and the hole diameter (D) is determined by doubling the radius (r). In this embodiment, for example, the opening area (S) of the third manifold portion 42 is 120 mm 2 and the depth (L) is 25 mm. Therefore, when the opening area (S) of the third manifold portion 42 is converted into a hole diameter (D), it becomes 12.4 mm, and the aspect ratio is 2.02. If there is a recess without an introduction path 44, the aspect ratio is 2.02. Furthermore, if there is one introduction path 44 in the third manifold portion 42, the opening area (S) of the introduction path 44 is 1 mm 2, and the depth (L) is 5 mm. Therefore, when the opening area (S) of the introduction path 44 is converted into a hole diameter (D), it becomes 1.12 mm, and when the introduction path 44 and the third manifold portion 42 are averaged according to the length in the through-hole direction to find the aspect ratio, it becomes (2.02 × 25 + 4.46 × 5) / 30, or 2.43. Furthermore, the aspect ratio referred to here refers to the "recess" that becomes the third manifold portion 42 and the introduction path 44 of the case member main body 140, which is not provided with the metal protective film 200 and the protective film 210, which will be described in detail later.

[0043] A compliance substrate 45 is bonded via an adhesive 225 to the surface of the communicating plate 15 on the liquid ejection surface 20a side where the first manifold portion 17 and the second manifold portion 18 open. This compliance substrate 45 seals the openings of the first manifold portion 17 and the second manifold portion 18 on the liquid ejection surface 20a side.

[0044] In this embodiment, the compliance substrate 45 includes a sealing film 46 and a fixed substrate 47. The sealing film 46 includes a flexible thin sealing film main body 146 made of a resin material, a metal protective film 200 (described in detail below) provided on the sealing film main body 146, and a protective film 210 (described in detail below) laminated on the metal protective film 200. Note that if the sealing film main body 146 has high ink resistance, the sealing film 46 may be composed of only the sealing film main body 146 without the metal protective film 200 or the protective film 210. However, for example, it is preferable that the sealing film 46 does not include the metal protective film 200, i.e., is composed of the sealing film main body 146 and the protective film 210. In the sealing film 46 of this embodiment, the surface on the −Z direction side of the sealing film main body 146 defines a portion of the first manifold portion 17 and the second manifold portion 18, which are flow paths. A metal protective film 200 and a protective film 210 are formed on the surface defining the first manifold portion 17 and the second manifold portion 18. The same resin material as that of the case member main body 140, i.e., polyphenylene sulfide (PPS) resin, ABS resin, polycarbonate, polyamide resin, phenolic resin, epoxy resin, modified polyphenylene ether resin, etc., can be used as the resin material for forming the sealing film main body 146. The thickness of the sealing film main body 146 is preferably 20 μm or less. By making the sealing film main body 146 20 μm or less, flexibility of the sealing film main body 146 can be ensured, and pressure fluctuations of the ink in the manifold 100 can be reduced by deformation of the sealing film main body 146.

[0045] The fixed substrate 47 is formed of a hard material such as a metal such as stainless steel (SUS) or a resin. The region of the fixed substrate 47 facing the manifold 100 is an opening 48 that is completely removed in the thickness direction, so one side of the manifold 100 is a compliance portion, which is a flexible portion sealed only with a flexible sealing film 46. Therefore, of the sealing film 46 of the compliance substrate 45 of this embodiment, the sealing film main body 146 corresponds to a "flow path forming member" formed of a resin material and defining the flow path. Of course, the sealing film main body 146 is not limited to being formed of a resin material, and may be formed of a metal material such as stainless steel. Of course, if the sealing film main body 146 is formed of a metal material, the sealing film main body 146 does not correspond to a "flow path forming member."

[0046] When ejecting ink from the recording head 1 configured as above, ink is taken in from an ink storage means such as a cartridge through the introduction channel 44, and the inside of the flow channel from the manifold 100 to the nozzle 21 is filled with ink. Thereafter, in accordance with a signal from the drive circuit 120, a voltage is applied to each piezoelectric actuator 300 corresponding to the pressure chamber 12, thereby deflecting and deforming the piezoelectric actuator 300 and the diaphragm 50. This increases the pressure within the pressure chamber 12, and ink droplets are ejected from the specified nozzle 21 in the +Z direction.

[0047] 3 and 4, a metallic protective film 200 made of a metallic material and a liquid-resistant protective film 210 are laminated in this order on at least the surface of the case member main body 140 that defines the flow path, that is, the surface that defines the introduction path 44 and the third manifold portion 42. In other words, the metallic protective film 200 is provided on the case member main body 140 side, and the protective film 210 is provided on the side of the metallic protective film 200 opposite the case member main body 140. In this embodiment, the metallic protective film 200 is provided continuously over the entire surface of the case member main body 140. In addition, the protective film 210 is provided on surfaces of the case member main body 140 other than the surfaces joined to other members, i.e., surfaces of the case member main body 140 other than the surfaces joined to the protective substrate 30 and the communicating plate 15, i.e., the inner surfaces of the third manifold portion 42 and the inlet path 44, which are flow paths, the inner surface of the connection port 43, the surface of the case member main body 140 in the -Z direction, and the outer surface of the case member main body 140 along the Z axis.

[0048] Furthermore, a metal protective film 200 made of the same metal material as that formed on the case member main body 140 and a liquid-resistant protective film 210 are laminated in this order on at least the surface of the sealing film main body 146 that defines the flow paths, i.e., the surface that defines the first manifold portion 17 and the second manifold portion 18. That is, the metal protective film 200 is provided on the sealing film main body 146 side, and the protective film 210 is provided on the side of the metal protective film 200 opposite the sealing film main body 146. In this embodiment, the metal protective film 200 is continuously formed over the entire surface of the assembly in which the sealing film main body 146 and the fixed substrate 47 are joined. Furthermore, the protective film 210 is provided on surfaces of the assembly other than the surface joined to the communicating plate 15, i.e., the surfaces that define the first manifold portion 17 and the second manifold portion 18, the inner surface of the opening 48, the surface in the +Z direction, and the outer surface along the Z axis of the assembly. Although the metal protective film 200 may be formed on the sealing film main body 146, from the viewpoint of flexibility, it is preferable to not have the metal protective film 200 or the protective film 210. Therefore, if the sealing film main body 146 has no problem with ink resistance, it is possible to provide only the protective film 210 on the sealing film main body 146 without providing the metal protective film 200, or it is not necessary to form both the metal protective film 200 and the protective film 210.

[0049] The protective film 210 extends from the surfaces of the case member main body 140 and the sealing film main body 146 that define the flow paths to the inner surfaces of the flow paths of other members. In other words, the protective film 210 extends to the inner surfaces that define the flow paths of the communicating plate 15, the flow path forming substrate 10, and the nozzle plate 20, i.e., the inner surfaces of the first manifold portion 17, the second manifold portion 18, the supply communication passage 19, the pressure chamber 12, the nozzle communication passage 16, and the nozzles 21. Therefore, the protective film 210 of this embodiment is continuously and uninterruptedly provided over the inner surfaces of the flow paths of the recording head 1, i.e., over the inner surfaces of the introduction passage 44, the manifold 100, the supply communication passage 19, the pressure chamber 12, the nozzle communication passage 16, and the nozzles 21. In this embodiment, the protective film 210 is also provided on the flow path side surfaces of the adhesives 220-225 that bond the various members that make up the recording head 1. In other words, the protective film 210 is provided continuously over the surfaces that define the flow paths of the case member main body 140 and the sealing film main body 146, which are made of a resin material, the surfaces that define the flow paths of the adherend member, which is made of a material other than a resin material, in this embodiment, the communicating plate 15, and the surfaces of the adhesives 224, 225 that join these together.

[0050] The metallic protective film 200 may be formed as a single layer of a single metal material or a composite material, or as a laminated film of multiple materials. In this embodiment, as shown in FIG. 4 , the metallic protective film 200 is formed by laminating a first metallic protective film 201, a second metallic protective film 202, and a third metallic protective film 203 in this order from the flow path forming member side. That is, the metallic protective film 200 has the third metallic protective film 203 as an "upper layer" on the protective film 210 side, and the second metallic protective film 202 as a "lower layer" on the case member main body 140 and sealing film main body 146 side, which are the flow path forming member main body, relative to the third metallic protective film 203. The metallic protective film 200 also has the first metallic protective film 201 as a "lowest layer" on the case member main body 140 and sealing film main body 146 side, which are the flow path forming member main body.

[0051] Examples of metal materials used for the first metal protective film 201 include nickel (Ni), copper (Cu), gold (Au), silver (Ag), and platinum (Pt). The first metal protective film 201 can be formed at low cost by using nickel (Ni) or copper (Cu). Examples of nickel (Ni) used for the first metal protective film 201 include nickel boron (Ni-B) containing boron (B) and nickel phosphorus (Ni-P) containing phosphorus (P). By including at least one of nickel boron and nickel phosphorus, the first metal protective film 201 can improve its liquid resistance and prevent the case member main body 140 and the sealing film main body 146 from being corroded or swollen by ink. Corrosion and swelling can not only reduce dimensional accuracy but also cause various problems, such as damage to the interior of components or joints due to dimensional changes, peeling of joints due to a decrease in the bonding strength of joints, and liquid leakage due to dissolution of components. These problems can be prevented.

[0052] Such first metal protective film 201 is preferably formed by electroless plating. By forming first metal protective film 201 by electroless plating, it can be easily formed on the inner surfaces of third manifold portion 42 and introduction path 44, which are flow paths provided in case member main body 140, even if the aspect ratio of third manifold portion 42 and introduction path 44 is 2 or more.

[0053] Furthermore, the first metal protective film 201 is preferably an alloy containing nickel and boron. This is because the solution temperature when forming a nickel-boron film by electroless plating is often lower than the solution temperature when forming a nickel-phosphorus film by electroless plating. This is because the film formation rate of electroless nickel boron (Ni-B) plating (also known as electroless nickel boron plating) is often faster than that of electroless nickel phosphorus (Ni-P) plating. Therefore, forming the first metal protective film 201 by electroless nickel boron plating can prevent the case member main body 140 and the sealing film main body 146, which are made of a resin material, from being deformed by the heat generated during electroless plating. However, when the first metal protective film 201 is formed by electroless nickel boron plating, strong tensile stress is generated as an internal stress in the formed film, making it prone to cracking and peeling as the film becomes thicker. For this reason, when forming first metal protective film 201 by electroless nickel boron plating, the thickness of first metal protective film 201 is preferably 0.3 μm or more and 0.5 μm or less. By keeping first metal protective film 201 within this thickness range, internal stress in first metal protective film 201 can be suppressed, preventing cracks from occurring in first metal protective film 201 and peeling of first metal protective film 201 from case member main body 140 or sealing film main body 146. Incidentally, when first metal protective film 201 is formed by electroless nickel phosphorus plating, internal stress varies depending on the phosphorus (P) concentration. For example, a phosphorus (P) content of 7% or less results in high tensile stress, and as the phosphorus (P) content increases, the tensile stress decreases or the compressive stress increases. For example, when the phosphorus (P) content is approximately 8.7%, the internal stress is nearly zero. Therefore, by using an alloy containing nickel and phosphorus as first metal protective film 201 and adjusting the phosphorus (P) content, first metal protective film 201 can be made less susceptible to cracking and peeling.

[0054] Examples of metal materials used for the second metal protective film 202 include copper (Cu), nickel (Ni), chromium (Cr), and zinc (Zn). Copper (Cu) is preferably used for the second metal protective film 202. Copper (Cu) has relatively small internal stress and is soft, so it can function as a stress relief layer that relieves the internal stress of the metal protective film 200. In this embodiment, copper (Cu) is used for the second metal protective film 202. Such a second metal protective film 202 is preferably formed by electrolytic plating. Forming the second metal protective film 202 by electrolytic plating allows a relatively thick film to be formed inexpensively. Furthermore, the second metal protective film 202 is preferably formed thicker than the first metal protective film 201. For example, the second metal protective film 202 is preferably formed to a thickness of 0.5 μm or more and 10 μm or less. By providing the second metal protective film 202 thicker than the first metal protective film 201, the overall thickness of the metal protective film 200 can be made relatively thick, preventing pinholes from forming in the metal protective film 200 and preventing the metal protective film 200 from falling off together with particles other than the resin material contained in the resin material, known as fillers. Fillers are materials other than resin, such as minerals such as silicon oxide, aluminum oxide, and zirconium oxide, glass fiber, ceramic fiber, and carbon, that are mixed into the resin material to improve properties such as increasing the strength, heat resistance, and various resistances of the resin, as well as to reduce costs and adjust color. The particle size of such fillers is, for example, approximately 0.1 μm to 100 μm.

[0055] The material used for the third metal protective film 203 is preferably a metallic material with high liquid resistance, such as nickel (Ni), chromium (Cr), zinc (Zn), palladium (Pd), nickel-palladium alloy (Ni-Pd alloy), nickel-tin alloy (Ni-Sn alloy), nickel-zinc alloy (Ni-Zn alloy), and gold (Au). Such third metal protective film 203 is preferably formed by electrolytic plating. By forming the third metal protective film 203 by electrolytic plating, a relatively thick film can be formed inexpensively.

[0056] Furthermore, it is preferable that the third metal protective film 203 be made of a material having a Mohs hardness greater than that of the second metal protective film 202. The Mohs hardness of representative metal elements is shown in Table 1 below.

[0057] [Table 1]

[0058] As shown in Table 1, when copper (Cu) is used as the second metal protective film 202, it is preferable that the third metal protective film 203 be made of a material having a Mohs hardness greater than that of copper (Cu), such as nickel (Ni) with a Mohs hardness of 3.8 or chromium (Cr) with a Mohs hardness of 9.0. In other words, it is preferable that the first metal protective film 201 and the second metal protective film 202, which correspond to the lower layers, contain copper (Cu), and the third metal protective film 203, which corresponds to the upper layer, contains at least one of nickel (Ni) and chromium (Cr). Thus, the first metal protective film 201 and the second metal protective film 202 contain copper (Cu), thereby improving the thermal conductivity of the metal protective film 200. Furthermore, by using a material for the third metal protective film 203 having a Mohs hardness greater than that of the second metal protective film 202, the surface of the metal protective film 200 is less susceptible to scratches. In particular, by using at least one of nickel (Ni) and chromium (Cr) as the third metal protective film 203, it is possible to prevent a significant decrease in the thermal conductivity of the metal protective film 200, and it is easy to form the third metal protective film 203 by electrolytic plating. In this embodiment, nickel (Ni) is used as the third metal protective film 203.

[0059] Furthermore, by forming the third metal protective film 203 on the second metal protective film 202 made of copper (Cu), internal stress is alleviated, making the film less likely to peel off. The third metal protective film 203 is preferably formed to a thickness of 0.5 μm or more and 10 μm or less. By providing the third metal protective film 203 in this manner, the overall thickness of the metal protective film 200 can be made relatively thick, preventing pinholes from forming in the metal protective film 200 and preventing the metal protective film 200 from falling off together with the filler contained in the resin material. Furthermore, by providing the third metal protective film 203 on the second metal protective film 202 made of copper (Cu), deterioration of the copper (Cu) surface of the second metal protective film 202 can be prevented.

[0060] The total thickness of the metallic protective film 200 including the first metallic protective film 201, the second metallic protective film 202, and the third metallic protective film 203 is preferably 1 μm or more. By making the thickness of the metallic protective film 200 1 μm or more, it is possible to prevent the filler contained in the resin material from falling off.

[0061] In the embodiment, the metal protective film 200 is provided with the first metal protective film 201, the second metal protective film 202, and the third metal protective film 203, but is not limited to this, and the metal protective film may be formed with only the first metal protective film 201 without the second metal protective film 202 and the third metal protective film 203, or may be formed by laminating the first metal protective film 201 and the second metal protective film 202 without the third metal protective film 203. However, when a film with high stress is used as the first metal protective film 201, the first metal protective film 201 needs to be formed relatively thin. Therefore, when it is desired to use a film with high stress, it is easy to mix low-stress films by providing a second metal protective film 202 and a third metal protective film 203 on the first metal protective film 201, or to mix and stack compressive stress films and tensile stress films, thereby reducing the stress of the entire film, making the overall film thickness of the metal protective film 200 relatively thick, and making it difficult for the metal protective film 200 to peel off from the case member 40.

[0062] The method for forming the metallic protective film 200 is not limited to plating such as electroless plating and electrolytic plating, and may be, for example, sputtering, physical vapor deposition (PVD), chemical vapor deposition (CVD), etc. However, forming the metallic protective film 200 by plating does not require a vacuum environment, and allows for the formation of a relatively thick film at low cost and allows for batch processing, further reducing costs.

[0063] By providing the metal protective film 200 in this manner, it is possible to improve the thermal conductivity of the flow path forming member main body formed of a resin material, i.e., the case member main body 140 and the sealing film main body 146. That is, although a resin material has lower thermal conductivity than a metal material, by providing the metal protective film 200 made of a metal material on the surfaces that define the flow paths of the case member main body 140 and the sealing film main body 146, which are formed of a resin material, it is possible to improve the thermal conductivity of the surfaces that define the flow paths of the case member main body 140 and the sealing film main body 146. In particular, by providing the metal protective film 200 on the inner surface of the common liquid chamber, i.e., the inner surface of the third manifold portion 42 that constitutes part of the manifold 100 of the case member main body 140, and on the surfaces that define the first manifold portion 17 and the second manifold portion 18 of the sealing film main body 146, it is possible to suppress the occurrence of temperature variations in the ink filled in the manifold 100 in the direction along the X-axis, which is the direction in which the pressure chambers 12 are arranged. Therefore, it is possible to suppress temperature variations in the ink supplied from the manifold 100 to the pressure chambers 12, which are the individual flow paths, and to suppress viscosity variations due to the ink temperature. This makes it possible to suppress variations in the ejection characteristics of the ink ejected from each nozzle 21, i.e., variations in the ink weight and ink flight speed, and improve print quality. In particular, as described above, since the second metal protective film 202 contains copper (Cu), it is possible to improve the thermal conductivity of the entire metal protective film 200 and suppress variations in the ejection characteristics of the ink ejected from each nozzle 21.

[0064] The protective film 210 is formed on the metallic protective film 200, or in this embodiment, on the third metallic protective film 203. The protective film 210 is formed of a single layer of a liquid-resistant material or composite material, or a laminated film of multiple materials. Here, liquid resistance refers to etching resistance against ink, which is a basic or acidic liquid, and resistance to dissolution and swelling in organic solvents. Since inorganic materials typically have high resistance to organic solvents, the liquid-resistant material used for the protective film 210 against basic or acidic liquids includes an oxide or nitride of one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y). That is, the protective film 210 may be a single layer of a single material or a composite material containing an oxide or nitride of the above elements, or may be a laminated film in which multiple materials are stacked.

[0065] The thickness of the protective film 210 is preferably thinner than the thickness of the metal protective film 200. By making the protective film 210 thinner than the metal protective film 200, it is possible to prevent the protective film 210 from interfering with the displacement of the sealing film 46. Furthermore, when the protective film 210 is extended to the inner surfaces of other flow paths as in this embodiment, it is possible to prevent the protective film 210 from interfering with the displacement of the vibration plate 50. Furthermore, by making the thickness of the metal protective film 200 thicker than the thickness of the protective film 210, it is possible to improve thermal conductivity. Note that because the protective film is thin, it is possible to reduce the decrease in thermal conductivity.

[0066] Such a protective film 210 preferably contains hafnium (Hf). Hafnium (Hf) is a compound of hafnium oxide (HfO X ) and other strongly basic and strongly acidic liquids. Therefore, by including hafnium (Hf) in the protective film 210, the protective film 210 is prevented from being corroded by ink, and the case member main body 140 and the sealing film main body 146 can be more reliably prevented from being corroded or swollen by ink.

[0067] Furthermore, the protective film 210 preferably contains silicon (Si). Silicon (Si) is highly hydrophilic to water, or has high wettability. Therefore, when the protective film 210 contains silicon (Si), it is possible to prevent air bubbles contained in the ink from remaining in the flow path when the ink is filled in the flow path, thereby improving bubble discharge performance. In other words, if air bubbles remain in the flow path, they function as a buffer when they enter the pressure chamber 12 or the nozzle 21 at an unexpected timing and cause a pressure change, resulting in ejection defects such as ink not being ejected or ink flight direction being shifted. By increasing the hydrophilicity of the protective film 210, it is possible to improve bubble discharge performance in the flow path and prevent ink ejection defects caused by air bubbles.

[0068] Incidentally, the material of the protective film 210 that satisfies the above two conditions is hafnium silicate (HfSiO X ) are listed.

[0069] Such a protective film 210 is formed by atomic layer deposition (ALD). Atomic layer deposition allows for the formation of a dense film with high film density, a uniform film thickness, and excellent adhesion to the target object even when the target object has an uneven shape. By forming the protective film 210 on the metal protective film 200 by atomic layer deposition, the protective film 210 can be formed uniformly throughout minute defects, such as pinholes and pits, formed in the metal protective film 200. Therefore, providing the protective film 210 prevents the surface of the resin material from being exposed in the flow path, and the protective film 210 can protect the resin material from ink.

[0070] The thickness of the protective film 210 is preferably 20 nm or more and 40 nm or less. If the protective film 210 is thinner than 20 nm, the protective performance of the case member main body 140 and the sealing film main body 146 formed of a resin material may be reduced. Furthermore, if the protective film 210 is thicker than 40 nm, it takes a long time to form the film by atomic layer deposition, resulting in high costs. In other words, by making the protective film 210 thicker than 20 nm and 40 nm or less, it is possible to reliably protect components formed of a resin material and reduce costs.

[0071] As described above, the protective film 210 is provided continuously over the surfaces that define the flow paths of the case member main body 140 and the sealing film main body 146, which are made of a resin material, the surfaces that define the flow paths of the bonded member made of a material other than resin, which in this embodiment is the communicating plate 15, and the surfaces of the adhesives 224 and 225 that bond these together. This prevents ink from penetrating and corroding the bonding interfaces between the case member main body 140 and the sealing film main body 146 and the communicating plate 15, and also prevents the adhesives 224 and 225 from being corroded by ink. This prevents the adhesive strength of the bonded members from being reduced by ink, and prevents peeling and leakage of ink to the outside.

[0072] A method for manufacturing the recording head 1 of this embodiment will now be described with reference to Figures 5 to 17. Figures 5 to 17 are cross-sectional views taken along line AA' showing the method for manufacturing the recording head 1.

[0073] 5, the case member main body 140, in which the third manifold portion 42, the introduction path 44, the connection port 43, etc. are formed, is formed from a resin material. The case member main body 140 can be manufactured inexpensively by, for example, injection molding.

[0074] Next, the case member main body 140 is immersed in a chromic acid solution or a permanganate solution to roughen the surface of the case member main body 140, forming irregularities on the surface. By forming irregularities on the surface of the case member main body 140, the adhesion of the metal protective film 200 formed on the surface of the case member main body 140 in a later process can be improved by an anchor effect.

[0075] Next, a catalyst for electroless plating is applied to the surface of the case member main body 140. The catalyst functions as a catalyst (activator) for electroless plating and contains palladium (Pd) as a main component. Catalyst application methods generally include dipping and spraying (spinning). In this embodiment, the dipping method involves immersing the object in a chemical solution. The spraying method involves spraying the chemical solution onto the object from a nozzle. In this embodiment, the palladium (Pd) catalyst is applied by immersing the case member main body 140 in a palladium chloride aqueous solution. Since the case member main body 140 has flow paths such as the third manifold portion 42 and the introduction path 44, applying the catalyst by dipping the case member main body 140 in a chemical solution allows the catalyst to be applied to the inner surfaces of the flow paths of the case member main body 140, etc., and also allows for batch processing, thereby improving the efficiency of the production process.

[0076] Next, as shown in FIG. 6, a first metal protective film 201 is formed on the surface of the case member main body 140. Examples of metal materials used for the first metal protective film 201 include nickel (Ni), copper (Cu), gold (Au), silver (Ag), and platinum (Pt). In this embodiment, nickel (Ni) is formed as the first metal protective film 201 by electroless plating. Specifically, the case member main body 140 is immersed in a plating solution containing nickel sulfate to form the first metal protective film 201 made of nickel (Ni) with a thickness of 0.3 to 0.5 μm. That is, as shown in FIG. 6, the electroless plating on the case member main body 140 is performed by immersing the case member main body 140 in a plating solution 401 held in a plating tank 400. In this electroless plating, it is preferable to relatively shake the case member main body 140 and the plating solution 401. Here, rocking the case member body 140 and the plating solution 401 relative to each other includes stirring the plating solution 401 and rocking the case member body 140. For example, it is preferable to use at least one method selected from the following: generating bubbles in the plating solution 401, stirring the plating solution 401 with a stirring rod, stirring the plating solution 401 with a stirring screw, and rocking the case member body 140. By rocking the case member body 140 and the plating solution 401 relative to each other in this manner, fresh plating solution 401 can constantly enter the surface of the case member body 140, particularly the third manifold portion 42, which is a groove, and the like, thereby forming a first metal protective film 201 with a relatively uniform thickness and few pinholes. Rocking the case member body 140 and the plating solution 401 relative to each other also removes dust adhering to the surface of the case member body 140, thereby forming a first metal protective film 201 with a relatively uniform thickness and few pinholes.

[0077] Furthermore, by forming the first metal protective film 201 by electroless plating, even if the aspect ratio of the third manifold portion 42 and the inlet path 44, which are flow paths provided in the case member main body 140 as described above, is 2 or more, the first metal protective film 201 can be easily formed on the inner surface of the third manifold portion 42 and the inlet path 44.

[0078] 7, second metal protective film 202 is formed on first metal protective film 201. Examples of metal materials used for second metal protective film 202 include copper (Cu), nickel (Ni), chromium (Cr), and zinc (Zn). In this embodiment, second metal protective film 202 is formed by electrolytic plating using copper (Cu) to a thickness of 5 μm. When forming second metal protective film 202 by electrolytic plating, it is preferable to relatively oscillate case member main body 140 and the plating solution used for electrolytic plating, as in the case of forming first metal protective film 201 by electroless plating.

[0079] 8, a third metal protective film 203 is formed on the second metal protective film 202. As a result, a metal protective film 200 consisting of the first metal protective film 201, the second metal protective film 202, and the third metal protective film 203 is formed on the case member main body 140. The metal material used for the third metal protective film 203 is preferably a metal material with high liquid resistance, such as nickel (Ni), chromium (Cr), zinc (Zn), palladium (Pd), a nickel-palladium alloy (Ni-Pd alloy), a nickel-tin alloy (Ni-Sn alloy), a nickel-zinc alloy (Ni-Zn alloy), or gold (Au). In this embodiment, a nickel (Ni) film is formed to a thickness of about 5 μm by electrolytic plating. Because second metal protective film 202 functions as a stress relief layer, third metal protective film 203 reduces the internal stress of metal protective film 200 as a whole, making third metal protective film 203 less likely to peel off from first metal protective film 201 and second metal protective film 202. Also, metal protective film 200 is less likely to peel off from case member main body 140. Furthermore, because second metal protective film 202 is soft, providing third metal protective film 203 can improve the strength of the surface of metal protective film 200, and providing second metal protective film 202 and third metal protective film 203 can make metal protective film 200 relatively thick.

[0080] When forming third metal protective film 203 by electrolytic plating, it is preferable to oscillate case member main body 140 and the plating solution relative to each other, as in the case when first metal protective film 201 is formed by electroless plating.

[0081] Furthermore, although not specifically shown, the metallic protective film 200 may also be formed on the sealing film main body 146 of the compliance substrate 45 by the same method as that for the case member 40 described above. The metallic protective film 200 may be formed on the sealing film main body 146 alone, and then the sealing film main body 146 on which the metallic protective film 200 has been formed may be bonded to the fixed substrate 47. The metallic protective film 200 may also be formed after the fixed substrate 47 and the sealing film main body 146 are bonded together to form an integrated body. In this embodiment, the metallic protective film 200 is formed after the fixed substrate 47 and the sealing film 46 are bonded together.

[0082] 9, a vibration plate 50 is formed on one surface of a flow path forming substrate wafer 110, which is a silicon wafer and will become a plurality of flow path forming substrates 10. In this embodiment, an elastic film 51 made of silicon dioxide is formed by thermally oxidizing the flow path forming substrate wafer 110, and then a zirconium film is formed on the elastic film 51 by sputtering, and then the zirconium film is thermally oxidized to form an insulating film 52 made of zirconium oxide. In this way, a vibration plate 50 is formed in which the elastic film 51 and the insulating film 52 are laminated.

[0083] Of course, the material of diaphragm 50 is not limited to silicon dioxide or zirconium oxide, and may be silicon nitride (Si3N4), titanium oxide (TiO2), aluminum oxide (Al2O3), hafnium oxide (HfO2), magnesium oxide (MgO), lanthanum aluminate (LaAlO3), etc. Furthermore, the method of forming elastic film 51 is not limited to thermal oxidation, and may be sputtering, physical vapor deposition (PVD), chemical vapor deposition (CVD), spin coating, or a combination of these.

[0084] 10, a piezoelectric actuator 300, an individual lead electrode 91, and a common lead electrode 92 (see FIG. 2) are formed on the diaphragm 50. Each layer of the piezoelectric actuator 300, the individual lead electrode 91, and the common lead electrode 92 can be formed for each pressure chamber 12 by film formation and lithography. The piezoelectric layer 70 can be formed using, for example, a sol-gel method, an MOD method, a sputtering method, a PVD method such as a laser ablation method, or the like.

[0085] 11 , a protective substrate wafer 130, which is a silicon wafer and will serve as a plurality of protective substrates 30, is bonded to the piezoelectric actuator 300 side of the flow path forming substrate wafer 110 via an adhesive 222. The protective substrate wafer 130 to be bonded to the flow path forming substrate wafer 110 has holding portions 31, through holes 32, and the like formed in advance, and the protective substrate wafer 130 and the flow path forming substrate wafer 110 are bonded together via the adhesive 222. Note that the method for forming the holding portions 31 and the through holes 32 in the protective substrate wafer 130 is not particularly limited, and they can be formed with high precision by anisotropic etching using an alkaline solution such as KOH, for example.

[0086] Next, as shown in FIG. 12, the flow path forming substrate wafer 110 is thinned to a predetermined thickness, and then the flow path forming substrate wafer 110 is anisotropically etched from the side opposite the protective substrate wafer 130 via a mask (not shown), thereby forming pressure chambers 12 corresponding to the piezoelectric actuators 300.

[0087] Next, as shown in FIG. 13, unnecessary portions of the flow path forming substrate wafer 110 and the protective substrate wafer 130 are removed, and the flow path forming substrate wafer 110 and the protective substrate wafer 130 are divided into a flow path forming substrate 10 and a protective substrate 30 of one chip size as shown in FIG. 1.

[0088] 14, a communication plate 15 is joined to the divided flow path forming substrate 10. This communication plate 15 has nozzle communication paths 16, a first manifold portion 17, a second manifold portion 18, and a supply communication path 19 formed therein in advance, and the communication plate 15 and the flow path forming substrate 10 are bonded together via an adhesive 220.

[0089] 15, the nozzle plate 20 is bonded to the communication plate 15. Nozzles 21 are formed in advance in the nozzle plate 20, and a liquid-repellent film 24 is formed on the liquid ejection surface 20a. The nozzle plate 20 and the communication plate 15 are bonded together via an adhesive 221.

[0090] 16, the case member main body 140 having the metal protective film 200 formed thereon is bonded to the communicating plate 15 and the protective substrate 30, and the sealing film main body 146 having the metal protective film 200 formed thereon and the fixed substrate 47 bonded to the communicating plate 15 is bonded thereto. The communicating plate 15, the protective substrate 30, and the case member main body 140 are bonded via an adhesive 224. The communicating plate 15 and the sealing film main body 146 are also bonded via an adhesive 225. In this way, an assembly is formed in which the flow path forming substrate 10, the protective substrate 30, the communicating plate 15, the nozzle plate 20, the case member main body 140, the sealing film main body 146, and the fixed substrate 47 are bonded together.

[0091] 17, a protective film 210 is formed on at least the inner surface of the flow path of the assembly by atomic layer deposition (ALD). That is, in this embodiment, the protective film 210 is formed after bonding the case member main body 140 and the sealing film main body 146, on which the protective film 210 is not formed, to the communicating plate 15, which is an adherend member that is adhered thereto and defines the flow path.

[0092] The material used for the protective film 210 includes an oxide or nitride of one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y). In this embodiment, hafnium oxide (HfO X ) was deposited to a thickness of 20 nm or more and 40 nm or less.

[0093] Furthermore, in this embodiment, by forming the protective film 210 on the assembly by atomic layer deposition, it is possible to form a continuous protective film 210 over the inner surfaces of the flow paths of the assembly, i.e., the inner surfaces of the manifold 100, the supply communication passage 19, the pressure chamber 12, the nozzle communication passage 16, and the nozzle 21. Furthermore, since the protective film 210 is formed after bonding the case member main body 140, the sealing film main body 146, and the communicating plate 15, which is an adherend that is bonded to these and defines the flow paths, the protective film 210 can also be formed continuously on the surfaces of the adhesives 224 and 225 on the flow path side. In other words, the protective film 210 can be formed over the case member main body 140, the adhesive 224, and the communicating plate 15 on the inner surface of the manifold 100, which is the flow path, and can also be formed over the sealing film main body 146, the adhesive 225, and the communicating plate 15. Therefore, it is possible to prevent ink from penetrating into the adhesive interface between the case member main body 140 and the sealing film main body 146 and the communicating plate 15, and the adhesives 224 and 225 can also be protected by the protective film 210, which prevents the adhesives 224 and 225 from being soaked with ink and prevents a decrease in adhesive strength.

[0094] In this embodiment, the protective film 210 is also provided on the outer circumferential surface of the bonded body. However, the protective film 210 is not provided on the area of ​​the nozzle plate 20 where the liquid-repellent film 24 is formed, and on the terminal portions of the individual lead electrodes 91 and the common lead electrode 92 to which the wiring board 121 is connected. When forming the protective film 210 in this manner, the areas where the protective film 210 should not be formed can be protected with protective tape or the like. Furthermore, by providing the protective film 210 on the outer circumferential surface of the bonded body, even if ink adheres to the outer circumferential surface of the bonded body, it is possible to suppress erosion or expansion by the ink.

[0095] In this embodiment, the protective film 210 is provided on substantially the entire surface of the bonded body, but the present invention is not limited to this, and the protective film 210 may be provided only on the inner surface of the flow path of the bonded body. For example, when the protective film 210 is formed only on the inner surface of the flow path, the outer circumferential surface may be protected by a protective tape, and the gas used in the ALD process may be introduced through the introduction path 44.

[0096] After forming the metallic protective film 200 of a metallic material on the case member main body 140 and the sealing film main body 146 formed of a resin material, the protective film 210 is then formed on the metallic protective film 200 by atomic layer deposition. This allows the case member main body 140 and the sealing film main body 146 formed of a resin material to be reliably protected from ink by the protective film 210. In other words, film formation by atomic layer deposition allows for a dense, highly dense film to be formed, resulting in a uniform film thickness and excellent adhesion to the target object, even if the target object has a highly irregular shape. Therefore, by forming the protective film 210 on the metallic protective film 200 formed on the case member main body 140 and the sealing film main body 146 by atomic layer deposition, the protective film 210 can be formed uniformly throughout minute defects, such as pinholes and pits, formed in the metallic protective film 200. Therefore, providing the protective film 210 prevents the surface of the resin material from being exposed, thereby protecting the case member 40 formed of a resin material from ink. Of course, the protective film 210 can also be formed in a dense state with high film density on the inner surfaces of the flow channels of the flow channel forming substrate 10, the communication plate 15, and the nozzle plate 20, which are made of materials other than resin materials, in this embodiment, silicon substrates. Therefore, members made of materials other than resin materials can be protected by the protective film 210.

[0097] For example, if the protective film 210 is formed directly on the case member main body 140 and the sealing film main body 146 made of a resin material by atomic layer deposition, pinholes or the like may occur due to gas generation from the resin material, particularly when heated during film formation. This may prevent the protective film 210 from being properly formed over the entire surface of the case member main body 140 and the sealing film main body 146. Furthermore, atomic layer deposition has a slow film formation rate, resulting in a relatively thin film compared to the metal protective film 200 formed by plating. Another reason for this is that the protective film 210 is not a metal but an oxide or nitride, which makes it difficult to increase ductility. Therefore, even if the protective film 210 is formed directly on the case member main body 140, the protective film 210 may fall off along with the filler contained in the resin material of the case member main body 140, resulting in pinholes or the like. Furthermore, forming a relatively thick protective film 210 by atomic layer deposition takes time to form and increases costs. In this embodiment, the protective film 210 is formed on the metallic protective film 200 by atomic layer deposition, thereby suppressing outgassing from the case member main body 140 and the sealing film main body 146, which are made of a resin material, when the protective film 210 is formed, thereby preventing pinholes and the like from occurring in the protective film 210 due to outgassing. Furthermore, by forming the metallic protective film 200 thicker than the protective film 210, the metallic protective film 200 makes it less likely for the filler contained in the resin material to fall off. Therefore, the case member main body 140 and the sealing film main body 146 can be reliably protected by the protective film 210, and costs can be reduced.

[0098] Thereafter, the wiring substrate 121 is electrically and mechanically connected to the individual lead electrodes 91 and the common lead electrode 92, thereby completing the recording head 1 of this embodiment shown in FIG.

[0099] (Test example) The test piece made of polycarbonate was designated as Sample 1.

[0100] Sample 2 was prepared by laminating a first metal protective film 201 made of nickel (Ni) with a thickness of 0.3 μm by electroless plating on the surface of a test piece made of polycarbonate, a second metal protective film 202 made of copper (Cu) with a thickness of 5 μm by electrolytic plating, and a third metal protective film 203 made of nickel (Ni) with a thickness of 5 μm by electrolytic plating.

[0101] A 30-nm-thick hafnium oxide (HfO) was deposited on the surface of the polycarbonate specimen by atomic layer deposition. X ) was formed on the protective film 210, which was designated as Sample 3.

[0102] Sample 4 was prepared by forming the same metal protective film 200 as in Sample 2 on the surface of a test piece made of polycarbonate, and then forming the same protective film 210 as in Sample 3 on this metal protective film 200.

[0103] These samples 1 to 4 were immersed in cyclohexanone at a temperature of 60°C for one week, and the rate of change in weight (also known as the expansion coefficient) between before and after immersion was measured. The results are shown in Table 2 below. Cyclohexanone is a main solvent often used in solvent inks for the purpose of dissolving resin films, which are recording media, to improve adhesion, and has high resin solubility. [Table 2]

[0104] As shown in Table 2, the test piece of Sample 1, which was not provided with the metallic protective film 200 or the protective film 210, lost 10.1% in weight. In other words, the expansion rate was -10.1%. The test piece of Sample 2, which was provided with only the metallic protective film 200, gained 0.9% in weight (in other words, the expansion rate was +0.9%). The test piece of Sample 3, which was provided with only the protective film 210, gained 2.1% in weight (in other words, the expansion rate was +2.1%). The test piece of Sample 4, which was provided with the metallic protective film 200 and the protective film 210, gained 0.03% in weight (in other words, the expansion rate was +0.03%). As can be seen from these results, it is believed that the weight loss in Sample 1 was due to the resin material dissolving in the solvent. Furthermore, when the metal protective film 200 or the protective film 210 is formed directly on the resin material, as in Samples 2 and 3, pinholes are formed in the metal protective film 200 and the protective film 210, and it is thought that the solvent seeps into the resin material through the pinholes, resulting in a large rate of weight change. In contrast, by laminating the metal protective film 200 and the protective film 210 on the resin material, as in Sample 4, it is possible to minimize the seepage of the solvent into the resin material.

[0105] As described above, the case member 40 and sealing film 46, which are flow path forming members of this embodiment, include the case member main body 140 and sealing film main body 146, which are flow path forming member main bodies formed of a resin material and which define at least a portion of the manifold 100, which is a flow path. The case member 40 and sealing film 46 also have a metallic protective film 200 formed of a metallic material, which is provided on at least the surfaces of the case member main body 140 and sealing film main body 146 that define the manifold 100. The case member 40 and sealing film 46 also include a protective film 210, which is laminated on the metallic protective film 200 and contains an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y).

[0106] In this way, by providing the protective film 210 containing an oxide or nitride of the above material, it is possible to improve the liquid resistance of the case member main body 140 and the sealing film main body 146, which are made of a resin material. Furthermore, by providing the metal protective film 200 on the case member main body 140 and the sealing film main body 146, it is possible to improve thermal conductivity and reduce unevenness in the temperature distribution of the liquid in the flow path.

[0107] In addition, in the case member 40 and the sealing film 46, which are the flow path forming members of this embodiment, it is preferable that the protective film 210 contains silicon (Si). By making the protective film 210 contain silicon (Si) in this way, the hydrophilicity of the protective film 210 with respect to water, that is, wettability, is improved, and air bubbles contained in the ink flowing in the flow path are prevented from remaining in the flow path, thereby improving the bubble discharge property.

[0108] In the case member 40 and the sealing film 46, which are the flow path forming members of this embodiment, the thickness of the metallic protective film 200 is preferably thicker than the thickness of the protective film 210. By making the metallic protective film 200 relatively thick, it is possible to prevent the metallic protective film 200 and the protective film 210 from falling off together with the filler contained in the resin material. Furthermore, by making the metallic protective film 200 relatively thick, it is possible to improve thermal conductivity.

[0109] Furthermore, in the case member 40, which is the flow path forming member of this embodiment, the resin material preferably contains non-resin particles. By including particles in the case member 40, it is possible to improve the properties of the resin material, such as strength and linear expansion coefficient. It is also possible to prevent the metal protective film 200 and the protective film 210 from falling off together with the filler contained in the resin material.

[0110] In the case member 40 and the sealing film 46, which are the flow path forming members of this embodiment, the metal protective film 200 preferably has a thickness of 1 μm or more. By making the metal protective film 200 thicker than 1 μm, it is possible to prevent the metal protective film 200 from falling off together with the filler contained in the resin material. It is also possible to improve the thermal conductivity of the resin material.

[0111] In the case member 40 and sealing film 46, which are flow path forming members of the present embodiment, the protective film 210 preferably contains hafnium (Hf). When the protective film 210 contains hafnium (Hf), which is resistant to strong basicity and strong acidity, the protective film 210 is prevented from being corroded by ink, and the case member main body 140 and the sealing film main body 146 can be more reliably prevented from being corroded or swollen by ink.

[0112] In the case member 40 and the sealing film 46, which are the flow path forming members of this embodiment, the metallic protective film 200 preferably contains copper (Cu). The metallic protective film 200 has a relatively small internal stress, and by containing soft copper (Cu), the internal stress of the metallic protective film 200 can be alleviated.

[0113] In the case member 40 and sealing film 46, which are flow path forming members of this embodiment, the metal protective film 200 preferably contains at least one of nickel phosphorus (Ni-P) and nickel boron (Ni-B). By using nickel phosphorus (Ni-P) and nickel boron (Ni-B), which have high liquid resistance, for the protective film 210, the liquid resistance of the case member main body 140 and sealing film main body 146 can be improved.

[0114] Furthermore, in the case member 40 and sealing film 46 that are the flow path forming members of this embodiment, the metal protective film 200 has a third metal protective film 203 that is an upper layer provided on the protective film 210 side, and a second metal protective film 202 that is a lower layer provided on the case member main body 140 and sealing film main body 146 side that are the flow path forming member main body relative to the third metal protective film 203, and it is preferable that the third metal protective film 203 has a Mohs hardness greater than that of the second metal protective film 202. In this way, by using a material for the third metal protective film 203 that has a Mohs hardness greater than that of the second metal protective film 202, the surface of the metal protective film 200 is less likely to be scratched, and the metal protective film 200 can protect the resin material.

[0115] In the case member 40 and sealing film 46, which are flow path forming members of this embodiment, the second metal protective film 202, which is the lower layer, preferably contains copper (Cu), and the third metal protective film 203, which is the upper layer, preferably contains at least one of nickel (Ni) and chromium (Cr). When the second metal protective film 202 contains copper (Cu), the thermal conductivity of the metal protective film 200 can be improved. Furthermore, using at least one of nickel (Ni) and chromium (Cr) as the third metal protective film 203 can prevent a significant decrease in the thermal conductivity of the metal protective film 200, and also makes it easier to form the third metal protective film 203 by electrolytic plating.

[0116] Furthermore, in the case member 40 and sealing film 46 that are the flow path forming members of this embodiment, the third manifold portion 42 and the introduction path 44 that are the flow paths are formed in grooves provided in the case member main body 140 that is the flow path forming member main body, and the grooves have an aspect ratio, which is the depth divided by the inlet diameter, of 2 or more, and it is preferable that the metal protective film 200 closest to the case member main body 140 contains at least one of nickel phosphorus (Ni-P) and nickel boron (Ni-B). Even if the grooves that become the flow paths formed in the case member main body 140 are relatively deep grooves with an aspect ratio of 2 or more, nickel phosphorus (Ni-P) and nickel boron (Ni-B) can be easily formed into films by electroless plating.

[0117] Furthermore, the ink jet recording head 1, which is an example of a liquid jet head according to this embodiment, is provided with the above-described flow path forming members, that is, the case member 40 and the sealing film 46. This makes it possible to improve the liquid resistance and thermal conductivity of the case member 40 and the sealing film 46, which are made of a resin material, and allows various inks to be jetted without being limited by the liquid resistance of the resin material itself.

[0118] Furthermore, the print head 1 of this embodiment includes a plurality of nozzles 21 that eject liquid, and supply communication paths 19, pressure chambers 12, and nozzle communication paths 16 that are individual flow paths provided for each nozzle 21, and the flow paths of the case member 40 and the sealing film 46 are preferably at least a part of a manifold 100 that is a common liquid chamber that communicates with all of the individual flow paths. This makes it possible to improve the thermal conductivity of the case member 40 and the sealing film 46 by using the metal protective film 200, thereby reducing unevenness in the temperature distribution of ink within the manifold 100. This makes it possible to suppress temperature variations in the ink supplied to each individual flow path from the manifold 100, and thereby suppress variations in the ejection characteristics of ink ejected from the nozzles 21.

[0119] In addition, a manufacturing method of the case member 40 and sealing film 46, which are examples of flow path forming members of this embodiment, includes forming a metallic protective film 200 of a metallic material on the surface of the case member main body 140 and sealing film main body 146, which are flow path forming member main bodies formed of a resin material and defining at least a portion of the flow path, at least defining the manifold 100, and then forming a protective film 210 containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y) on the metallic protective film 200 by atomic layer deposition. In this way, by forming the metallic protective film 200 on the case member main body 140 and sealing film main body 146 made of a resin material and then forming the protective film 210 by atomic layer deposition, even if pinholes are formed in the metallic protective film 200, the protective film 210 can be formed all the way to the inside of the pinholes. Therefore, protective film 210 can improve the liquid resistance of case member main body 140 and sealing film main body 146. Furthermore, unlike when protective film 210 is formed on the surface of a resin material, it is formed on metal protective film 200, which suppresses degassing from the resin material and can prevent pinholes and the like from occurring in protective film 210 due to degassing.

[0120] In the method for manufacturing the case member 40 and sealing film 46, which are flow path forming members of this embodiment, it is preferable that the first metal protective film 201, which is the bottom layer on the side of the case member main body 140 and sealing film main body 146, which are the flow path forming member main body, be formed by electroless plating. The first metal protective film 201 can be easily formed in the grooves that become the flow paths of the case member main body 140 and sealing film main body 146, and costs can be reduced.

[0121] In addition, in the manufacturing method of the case member 40 and the sealing film 46, which are flow path forming members of this embodiment, it is preferable to form the metal protective film 200 by electroless plating and electrolytic plating. This allows a layer with a relatively thick film thickness to be formed by electrolytic plating. Therefore, the relatively thick metal protective film 200 can prevent the filler contained in the resin material from falling off.

[0122] Furthermore, in the manufacturing method of the case member 40 and sealing film 46 serving as flow path forming members according to this embodiment, it is preferable to relatively agitate the case member main body 140 and sealing film main body 146, which are the flow path forming member main bodies, and the plating solution 401 when forming the metal protective film 200 by plating. By agitating the case member main body 140, sealing film main body 146, and plating solution 401 relative to each other in this manner, fresh plating solution 401 can always be introduced onto the surfaces of the case member main body 140 and sealing film main body 146, particularly into the third manifold portion 42, which is a groove formed in the case member main body 140. Therefore, it is possible to form a first metal protective film 201 with a relatively uniform thickness and few pinholes. Furthermore, by agitating the case member main body 140, sealing film main body 146, and plating solution 401 relative to each other, it is possible to remove dust adhering to the surfaces of the case member main body 140 and sealing film main body 146, thereby forming a first metal protective film 201 with a relatively uniform thickness and few pinholes.

[0123] Furthermore, the method for manufacturing the ink jet recording head 1, which is an example of the liquid jet head of this embodiment, includes the method for manufacturing the flow path forming member described above, and the recording head 1 having high liquid resistance can be easily manufactured.

[0124] Furthermore, in the manufacturing method of the recording head 1 of this embodiment, it is preferable to provide the case member 40 and sealing film 46, which are flow path forming members, and the communicating plate 15, which is an adherend member that is adhered to the case member 40 and sealing film 46 and defines the manifold 100, and to form the protective film 210 after adhering the case member main body 140 and sealing film main body 146, which are the flow path forming member main body, to the communicating plate 15. Since the liquid resistance of the adhesives 224 and 225 that adhere the case member main body 140 and sealing film main body 146 to the communicating plate 15 can be improved, it is also possible to use a material with low liquid resistance for the adhesives 224 and 225 themselves.

[0125] (Embodiment 2) 18 is a cross-sectional view of an ink jet recording head 1, which is an example of a liquid jet head according to Embodiment 2 of the present invention. Note that the same members as those in the above-described embodiments are given the same reference numerals, and redundant explanations will be omitted.

[0126] 18, the case member 40, which is a flow path forming member constituting the recording head 1 of this embodiment, has a case member main body 140 made of a resin material, a metal protective film 200, and a protective film 210. The metal protective film 200 and the protective film 210 are provided continuously over the entire surface of the case member main body 140.

[0127] Such a metallic protective film 200 and protective film 210 are the same as those in the first embodiment, and therefore a duplicated description will be omitted.

[0128] Moreover, the metal protective film 200 and the protective film 210 are formed by depositing the film on the case member main body 140 in a standalone state.

[0129] The sealing film 46 has a sealing film main body 146 made of a resin material, a metal protective film 200, and a protective film 210. The metal protective film 200 and the protective film 210 are provided continuously over the entire surface of the bonded body of the sealing film main body 146 and the fixed substrate 47. The metal protective film 200 and the protective film 210 are the same as those in the first embodiment, and therefore a duplicated description will be omitted.

[0130] Furthermore, the metal protective film 200 and the protective film 210 are formed by forming a single bonded body of the sealing film main body 146 and the fixed substrate 47. Of course, the metal protective film 200 and the protective film 210 may be formed on the sealing film main body 146 alone to form the sealing film 46, and then the sealing film 46 and the fixed substrate 47 may be bonded to each other.

[0131] Furthermore, a liquid-resistant flow path protective film 230 is formed on the inner surfaces of the flow paths of the flow path forming substrate 10, the communication plate 15, and the nozzle plate 20 that constitute the recording head 1, i.e., the first manifold portion 17, the second manifold portion 18, the supply communication passages 19, the pressure chambers 12, the nozzle communication passages 16, and the nozzles 21. The flow path protective film 230 may be made of the same material as the protective film 210, such as an oxide or nitride of an element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y). The flow path protective film 230 may be a single layer formed from a single material or a composite material, or may be a laminated film formed by laminating multiple materials. The flow path protective film 230 is preferably formed by atomic layer deposition (ALD). Because the flow path forming substrate 10, the communication plate 15, and the nozzle plate 20 are formed from silicon substrates, a dense film can be formed by directly depositing the flow path protective film 230 by atomic layer deposition. Of course, the method for depositing the flow path protective film 230 is not limited to atomic layer deposition, and sputtering, physical vapor deposition (PVD), chemical vapor deposition (CVD), plating, etc. may also be used. However, atomic layer deposition is the most preferable method, as it allows for thin films and is less likely to produce pinholes. Of course, the flow path protective film 230 may be formed on each of the components, such as the flow path forming substrate 10, the protective substrate 30, the communication plate 15, and the nozzle plate 20, when they are individually attached. However, by depositing the flow path protective film 230 on these components when they are joined together, the flow path protective film 230 can protect the flow path-side surfaces of the adhesives 220-222 and improve liquid resistance.

[0132] Such a flow path protective film 230 is formed in the state shown in Fig. 15 of the above-described first embodiment. Of course, similar to the above-described first embodiment, the film may be formed in a state in which the flow path forming substrate 10, the protective substrate 30, the communication plate 15, the nozzle plate 20, the case member 40, and the compliance substrate 45 are adhered. In this case, the metal protective film 200, the protective film 210, and the flow path protective film 230 are laminated in this order on the case member main body 140 and the sealing film main body 146. In other words, the protective film 210 and the flow path protective film 230 correspond to the "protective film" recited in the claims.

[0133] In this embodiment, the flow path side surfaces of the adhesives 224 and 225 are not covered by the protective film 210 and the flow path protective film 230, and therefore a highly liquid-resistant material must be used for the adhesives 224 and 225. However, because the protective film 210 is formed at the adhesive interface between the case member 40 and the sealing film 46 and the communicating plate 15, it is possible to prevent the case member 40 and the sealing film 46 from being damaged by ink that has penetrated into the adhesive interface.

[0134] (Other embodiments) Although the embodiments of the present invention have been described above, the basic configuration of the present invention is not limited to those described above.

[0135] For example, in each of the above-described embodiments, the metal protective film 200 is provided with three layers, namely, the first metal protective film 201, the second metal protective film 202, and the third metal protective film 203, but this is not particularly limited to this, and the metal protective film may be one layer, two layers, or four or more layers may be stacked.

[0136] Furthermore, in each of the above-described embodiments, the case member 40 and the sealing film 46 are exemplified as flow path forming members of the recording head 1, but this is not particularly limited to this, and a flow path forming member having a flow path connected to the inlet path 44 of the case member 40 may also be similarly configured with a flow path forming member main body formed of a resin material, a metal protective film 200, and a protective film 210.

[0137] In addition, in the above-described embodiments, the thin-film piezoelectric actuator 300 has been used as the pressure generating means for generating a pressure change in the pressure chamber 12, but the present invention is not limited to this, and other types of piezoelectric actuators may be used, such as thick-film piezoelectric actuators formed by methods such as attaching green sheets, or longitudinal vibration piezoelectric actuators in which piezoelectric material and electrode-forming material are alternately laminated and expanded and contracted in the axial direction. The pressure generating means may also be a so-called electrostatic actuator in which a heating element is disposed in the pressure generating chamber and bubbles are generated by the heat generated by the heating element to eject droplets from the nozzle 21, or a so-called electrostatic actuator in which static electricity is generated between a vibration plate and an electrode and the electrostatic force deforms the vibration plate to eject droplets from the nozzle 21.

[0138] The ink jet recording head 1 of each of these embodiments is mounted on an ink jet recording apparatus I, which is an example of a liquid ejecting apparatus. Figure 19 is a schematic diagram showing an example of the ink jet recording apparatus I.

[0139] In the ink jet recording apparatus I shown in Fig. 19, a recording head 1 is provided with a detachable cartridge 2 constituting an ink supply means, and is mounted on a carriage 3. The carriage 3 on which the recording head 1 is mounted is provided so as to be movable in the axial direction of a carriage shaft 5 attached to the apparatus main body 4.

[0140] The driving force of the drive motor 6 is transmitted to the carriage 3 via multiple gears and a timing belt 7 (not shown), causing the carriage 3 carrying the recording head 1 to move along the carriage shaft 5. Meanwhile, the device body 4 is provided with a transport roller 8 as a transport means, and a recording sheet S, which is a recording medium such as paper, is transported by the transport roller 8. Note that the transport means for transporting the recording sheet S is not limited to a transport roller, and may be a belt, a drum, or the like.

[0141] In such an inkjet recording device I, the recording sheet S is transported in the +X direction relative to the recording head 1, and the carriage 3 is moved back and forth in the direction along the Y axis relative to the recording sheet S, while ink droplets are ejected from the recording head 1, causing the ink droplets to land over almost the entire surface of the recording sheet S, thereby performing so-called printing.

[0142] Furthermore, in the inkjet recording device I described above, the recording head 1 is mounted on a carriage 3 and moves back and forth in the Y direction, which is the main scanning direction, but the present invention is not limited to this. For example, the present invention can also be applied to a so-called line-type recording device in which the recording head 1 is fixed and printing is performed simply by moving a recording sheet S, such as paper, in the X direction, which is the sub-scanning direction.

[0143] In the above embodiment, an inkjet recording head is used as an example of a liquid jet head, and an inkjet recording device is used as an example of a liquid jet device. However, the present invention is directed to a wide range of liquid jet heads and liquid jet devices, and can of course be applied to liquid jet heads and liquid jet devices that jet liquids other than ink. Examples of other liquid jet heads include various recording heads used in image recording devices such as printers, colorant jet heads used in manufacturing color filters for liquid crystal displays, electrode material jet heads used in forming electrodes for organic EL displays, FEDs (field emission displays), and bioorganic material jet heads used in manufacturing biochips, and the present invention can also be applied to liquid jet devices equipped with such liquid jet heads.

[0144] Furthermore, the present invention is not limited to flow path forming members used in liquid jet heads such as ink jet recording heads, but can also be applied to flow path forming members used in other devices. [Explanation of symbols]

[0145] I...inkjet recording apparatus (liquid ejection apparatus), 1...inkjet recording head (liquid ejection head), 2...cartridge, 3...carriage, 4...apparatus main body, 5...carriage shaft, 6...drive motor, 7...timing belt, 8...transport roller, 10...flow path forming substrate, 12...pressure chamber, 15...communicating plate, 16...nozzle connecting path, 17...first manifold portion, 18...second manifold portion, 19...supply connecting path, 20...nozzle plate, 20a...liquid ejection surface, 21...nozzle, 24...liquid-repellent film, 30...protective substrate, 31...holding portion, 32...through hole, 40...case member, 41...recess, 42...third manifold portion, 43...connecting port, 44...introduction path, 45...compliance substrate, 46...sealing film, 47...fixed substrate, 48...opening, 50...diaphragm, 51...elastic film, 52...insulating film, 60...first electrode, 70...piezoelectric layer, 71...recess, 80...second electrode, 91...individual lead electrode, 92...common lead electrode, 100...manifold, 110...flow path forming substrate wafer, 120...drive circuit, 121...wiring substrate, 130...protection substrate wafer, 140...case member main body, 146...sealing film main body, 200...metal protective film, 201...first metal protective film, 202...second metal protective film, 203...third metal protective film, 210...protective film, 220-225...adhesive, 230...flow path protective film, 300...piezoelectric actuator, 400...plating tank, 401...plating solution, S...recording sheet

Claims

1. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide of at least one element selected from the group consisting of titanium (Ti), niobium (Nb), vanadium (V), hafnium (Hf), and tungsten (W); Equipped with A flow path forming member characterized by:

2. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing a nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), tungsten (W), and yttrium (Y); Equipped with A flow path forming member characterized by:

3. The protective film contains hafnium (Hf).

3. The flow path forming member according to claim 1 or 2.

4. The protective film contains silicon (Si). The flow path forming member according to any one of claims 1 to 3.

5. The thickness of the metal protective film is greater than the thickness of the protective film. The flow path forming member according to any one of claims 1 to 4.

6. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y); Equipped with The resin material includes non-resin particles. A flow path forming member characterized by:

7. The metal protective film has a thickness of 1 μm or more.

7. The flow path forming member according to claim 1, wherein the flow path forming member is a flow path forming member.

8. A flow path forming member body formed of a resin material and defining at least a portion of a flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing a nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), tungsten (W), and yttrium (Y); Equipped with The metal protective film contains copper (Cu). A flow path forming member characterized by:

9. A flow path forming member body formed of a resin material and defining at least a portion of a flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y); Equipped with The metal protective film contains copper (Cu). A flow path forming member characterized by:

10. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y); Equipped with the metallic protective film contains at least one of nickel phosphorus (Ni—P) and nickel boron (Ni—B); A flow path forming member characterized by:

11. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y); Equipped with the metal protective film includes an upper layer provided on the protective film side and a lower layer provided on the flow path forming member main body side of the upper layer, and the upper layer has a Mohs hardness greater than that of the lower layer; A flow path forming member characterized by:

12. the lower layer contains copper (Cu), and the upper layer contains at least one of nickel (Ni) and chromium (Cr); The flow path forming member according to claim 11 .

13. a flow path forming member main body formed of a resin material and defining at least a part of the flow path; a metal protective film formed of a metal material and provided on at least a surface of the flow path forming member body that defines the flow path; a protective film laminated on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y); Equipped with the flow path is formed in a groove provided in the flow path forming member body, and the groove has an aspect ratio, calculated by dividing the depth by the inlet diameter, of 2 or more; the metal protective film closest to the flow path forming member body contains at least one of nickel phosphorus (Ni—P) and nickel boron (Ni—B); A flow path forming member characterized by:

14. A liquid jet head comprising the flow path forming member according to any one of claims 1 to 13.

15. The liquid ejection device includes a plurality of nozzles for ejecting liquid, and an individual flow path provided for each of the nozzles, The liquid jet head according to claim 14 , wherein the flow path of the flow path forming member is at least a part of a common liquid chamber that is in communication with a plurality of the individual flow paths.

16. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 14 or 15.

17. A flow path forming member body is made of a resin material and defines at least a part of a flow path. A metal protective film of a metal material is formed by electroless plating on at least the surface defining the flow path of the flow path forming member body, and at least the bottom layer on the flow path forming member body side is then formed by atomic layer deposition on the metal protective film, the protective film containing an oxide or nitride of at least one element selected from the group consisting of tantalum (Ta), titanium (Ti), zirconium (Zr), niobium (Nb), vanadium (V), hafnium (Hf), silicon (Si), aluminum (Al), tungsten (W), and yttrium (Y). A method for manufacturing a flow path forming member, comprising:

Images