Head chip, liquid ejecting head, liquid ejecting recording apparatus, and method of manufacturing head chip

Abstract

The invention provides a head chip, a liquid ejecting head, a liquid ejecting recording apparatus, and a method for manufacturing the head chip, wherein the head chip suppresses disconnection of a drive electrode and the like and has excellent reliability over a long period of time. A head chip according to one embodiment of the present disclosure is provided with: a chip main body having a pressure chamber for accommodating a liquid and a drive unit disposed in a portion facing the pressure chamber; a drive electrode formed in the drive unit; and a drive wiring that is formed on the chip main body and connects the drive electrode and the external wiring. The drive wiring includes: a first wiring portion having a first region and a second region connected to the first region in an extension direction of the drive wiring, the second region having a cross-sectional area orthogonal to the extension direction smaller than that of the first region; and a second wiring section that is continuous in a direction intersecting the extension direction with respect to at least the second region.

Description

Technical Field

[0001] The present disclosure relates to a head chip, a liquid ejecting head, a liquid ejecting recording apparatus, and a method for manufacturing the head chip. Background Art

[0002] The head chip used in an inkjet printer includes an actuator plate with ejection channels and non-ejection channels, and a nozzle plate with nozzle holes connected to the ejection channels. Individual electrodes are formed on the inner side surfaces of the ejection channels, extending along the ejection channels. Common electrodes are formed on the inner side surfaces of the non-ejection channels, extending along the non-ejection channels. In the head chip, a voltage is applied between the common electrode and the individual electrodes to cause the drive wall to deform by thickness slip, thereby changing the volume in the ejection channel. As a result, ink in the ejection channel is ejected through the nozzle holes formed in the nozzle plate.

[0003] The individual electrodes and the common electrode are connected to external wiring via individual terminals and the common terminal formed on the surface of the actuator plate (for example, see Patent Document 1 below). In Patent Document 1 below, a dividing groove is formed in a portion of the surface of the actuator plate between the individual terminals and the common terminal to separate the individual terminals from the common terminal. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-151495. Summary of the Invention Problems to be solved by the invention

[0005] However, in the aforementioned prior art, the dividing grooves extend onto the inner side of the non-ejection channel. Therefore, the cross-sectional area of ​​the common electrode, perpendicular to the extension direction, is smaller in the portion with the dividing grooves than in the portion without them. In other words, the resistance of the portion of the common electrode with the dividing grooves is higher than that of the portion without them. As a result, the portion of the common electrode with the dividing grooves can cause disconnection and other issues when high current flows through it.

[0006] The present disclosure provides a head chip, a liquid jet head, a liquid jet recording device, and a method for manufacturing a head chip that suppress disconnection of drive electrodes and have excellent long-term reliability. Solutions to Problems

[0007] In order to solve the above-mentioned problems, the present disclosure adopts the following means. (1) A head chip according to one embodiment of the present disclosure comprises: a chip body having a pressure chamber for accommodating liquid and a drive portion arranged at a portion facing the pressure chamber; a drive electrode formed in the drive portion; and a drive wiring formed in the chip body and connecting the drive electrode to an external wiring, wherein the drive wiring comprises: a first wiring portion having a first region and a second region, the second region being connected relative to the first region in an extension direction of the drive wiring and having a smaller cross-sectional area perpendicular to the extension direction than that of the first region; and a second wiring portion being connected at least relative to the second region in a direction intersecting the extension direction.

[0008] According to this solution, by forming the second wiring portion of the drive wiring so that it is connected to at least a second region of the first wiring portion, which has a smaller cross-sectional area than the first region, the maximum resistance of the entire drive wiring can be reduced. This prevents breakage of the drive wiring, even when an unexpectedly large current flows through the drive wiring. As a result, a head chip with excellent long-term reliability can be provided.

[0009] (2) In the head chip according to the above-mentioned aspect (1), it is preferable that the second wiring portion is provided only in a portion of the driving wiring including the second region. According to this aspect, by providing the second wiring portion only in a portion including the second region, the increase in material cost of the driving wiring associated with the addition of the second wiring portion can be suppressed compared to the case where the second wiring portion is formed so as to cover the entire first wiring portion.

[0010] (3) In the head chip involved in the above-mentioned scheme (1) or (2), it is preferred that the above-mentioned second wiring portion is arranged in a manner that covers at least the above-mentioned second area in the first direction orthogonal to the film forming surface of the above-mentioned drive wiring in the above-mentioned chip body when viewed from the above-mentioned extension direction. According to this embodiment, by providing the second wiring portion so as to cover the second region, the increase in size of the drive wiring along the film formation surface associated with the addition of the second wiring portion can be suppressed. This reduces the maximum resistance of the entire drive wiring while suppressing an increase in electrostatic capacitance.

[0011] (4) In the head chip involved in any one of the schemes (1) to (3) above, it is preferred that the second wiring portion is arranged in a manner that is integrally connected to at least the second region in the second direction along the film forming surface of the drive wiring in the chip body when viewed from the extension direction. According to this solution, by connecting the second wiring portion to the second region along the film formation surface, the risk of wire breakage can be further reduced. In particular, by ensuring the width of the drive wiring as in this solution, compared to ensuring the thickness of the drive wiring, when the cross-sectional area perpendicular to the extension direction is the same, the risk of film formation defects due to foreign matter adhesion can be reduced.

[0012] (5) In the head chip involved in any one of the schemes (1) to (4) above, it is preferred that the chip body includes an actuator plate formed by stacking two piezoelectric substrates whose polarization directions are different in the second direction along the second direction, and the actuator plate is provided with: an injection channel as the pressure chamber for accommodating liquid; and a non-injection channel adjacent to the injection channel and not accommodating liquid, the driving portion is composed of a portion of the actuator plate located between the injection channel and the non-injection channel, the driving electrode includes: a common electrode, a portion of the driving portion facing the injection channel is formed over the entire area in the second direction; and a separate electrode, a portion of the driving portion facing the non-injection channel is formed over the entire area in the second direction, and the driving wiring is connected to the separate electrode at a portion of the driving portion facing the non-injection channel. According to this solution, in an actuator plate composed of two piezoelectric substrates with different polarization directions, it is necessary to form a drive electrode (e.g., a separate electrode) across the entire area of ​​the drive portion in the second direction. Therefore, by forming the drive wiring in the portion of the drive portion that faces the non-ejection channel, the second wiring portion can be used to expand the drive wiring in the second direction when forming the separate electrode. This eliminates the need for a separate wiring formation step for forming the second wiring portion, thereby suppressing the decrease in manufacturing efficiency associated with forming the second wiring portion.

[0013] (6) In the head chip involved in any one of the schemes (1) to (5) above, it is preferred that a dividing groove is formed on the surface of the actuator plate, the dividing groove separating the common terminal connecting the common electrode and the external wiring from the individual terminal connecting the individual electrode and the external wiring, and the portion of the second area facing the non-injection channel in the driving portion is located at a portion overlapping with the dividing groove in the extension direction. According to this aspect, the second wiring portion is formed in the portion overlapping the dividing groove in the extending direction, thereby suppressing short circuits between the common terminal and the individual terminals and reducing the maximum resistance value of the entire drive wiring.

[0014] (7) A liquid ejecting head according to one aspect of the present disclosure includes the head chip according to any one of the aspects (1) to (6) above. According to this aspect, a liquid ejecting head having excellent reliability can be provided.

[0015] (8) A liquid jet recording apparatus according to one aspect of the present disclosure includes the liquid jet head according to the aspect (7) above. According to this aspect, a liquid jet recording apparatus with excellent reliability can be provided.

[0016] (9) A method for manufacturing a head chip according to one embodiment of the present disclosure includes a drive wiring forming step, wherein the drive wiring forming step forms drive wiring for connecting a drive electrode to an external wiring on a chip body, wherein the chip body has a pressure chamber for accommodating a liquid and a drive portion arranged at a portion facing the pressure chamber and having the drive electrode formed thereon. The drive wiring forming step forms a second wiring portion on the chip body having a first region and a second region so as to be connected at least relative to the second region in a direction intersecting the extension direction, wherein the second region is connected relative to the first region in the extension direction of the drive wiring and has a smaller cross-sectional area perpendicular to the extension direction than that of the first region. Effects of the Invention

[0017] According to one aspect of the present disclosure, a head chip, a liquid jet head, a liquid jet recording apparatus, and a method for manufacturing a head chip that suppress disconnection of drive electrodes and have excellent long-term reliability can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of a printer according to the first embodiment. Figure 2 This is a schematic structural diagram of the inkjet head and ink circulation mechanism according to the first embodiment. Figure 3 This is an exploded perspective view of the head chip according to the first embodiment. Figure 4 It is along Figure 3 Cross-sectional view along line IV-IV. Figure 5 It is along Figure 3 Cross-sectional view of line VV. Figure 6 is with Figure 5 The cross-sectional view corresponding to the VI-VI line. Figure 7 is with Figure 5 The cross-sectional view corresponding to line VII-VII. Figure 8 is with Figure 4 The cross-sectional view corresponding to the line VIII-VIII. Figure 9 yes Figure 4 Magnified view of part IX. Figure 10 is with Figure 4 The cross-sectional view corresponding to line XX. Figure 11 This is a flowchart for explaining the method for manufacturing the head chip according to the first embodiment. Figure 12 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 13 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 14 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 15 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 16 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 17 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 18 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 19 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 20 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 21 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 22 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 23 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 24 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 25 These are process diagrams for explaining the method for manufacturing the head chip according to the first embodiment. Figure 26 The head chip according to the second embodiment and Figure 5 Corresponding cross-sectional view. Figure 27 The head chip according to the second embodiment and Figure 7Cross-sectional view of the corresponding part. Figure 28 Regarding the head chip involved in the modification example, Figure 5 Corresponding cross-sectional view. Figure 29 Regarding the head chip involved in the modification example, Figure 7 Cross-sectional view of the corresponding part. DETAILED DESCRIPTION

[0019] Hereinafter, the embodiments involved in the present disclosure will be described with reference to the accompanying drawings. In the embodiments or modifications described below, the corresponding structures are sometimes marked with the same figure marks and the description is omitted. In the following description, expressions such as "parallel" or "orthogonal", "center", "coaxial", etc. that show relative configuration or absolute configuration not only indicate such a configuration strictly, but also indicate a state of relative displacement at an angle or distance with a tolerance or a degree that the same function can be obtained. In the following embodiment, an inkjet printer (hereinafter referred to as a printer) that uses ink (liquid) to record on a recording medium is illustrated as an example. In the drawings used in the following description, the scale of each component is appropriately changed to make each component a recognizable size.

[0020] (First embodiment) [Printer 1] Figure 1 This is a schematic diagram of the configuration of the printer 1 . like Figure 1 As shown, the printer (liquid jet recording apparatus) 1 of the first embodiment includes a pair of transport mechanisms 2 and 3 , an ink tank 4 , an inkjet head (liquid jet head) 5 , an ink circulation mechanism 6 , and a scanning mechanism 7 .

[0021] In the following description, an orthogonal coordinate system of X, Y, and Z is used as needed. In this case, the X direction is consistent with the conveying direction (sub-scanning direction) of the recording medium P (for example, paper, etc.). The Y direction is consistent with the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction shows the height direction (gravity direction) that is perpendicular to the X direction and the Y direction. In the following description, the arrow side in the figure in the X direction, the Y direction, and the Z direction is described as the positive (+) side and the side opposite to the arrow is described as the negative (-) side. In the first embodiment, the +Z side corresponds to the upper side in the direction of gravity, and the -Z side corresponds to the lower side in the direction of gravity.

[0022] The transport mechanisms 2 and 3 transport the recording medium P toward the +X side. The transport mechanisms 2 and 3 each include a pair of rollers 11 and 12 extending in the Y direction, for example. The ink tanks 4 contain, for example, four colors of ink, namely, yellow, magenta, cyan, and black. Each inkjet head 5 is configured to eject four colors of ink, namely, yellow, magenta, cyan, and black, in accordance with the connected ink tank 4 .

[0023] Figure 2 This is a schematic diagram of the structure of the inkjet head 5 and the ink circulation mechanism 6. like Figure 1 、 Figure 2 As shown, the ink circulation mechanism 6 circulates ink between the ink tank 4 and the inkjet head 5. Specifically, the ink circulation mechanism 6 includes a circulation flow path 23 having an ink supply tube 21 and an ink discharge tube 22; a pressure pump 24 connected to the ink supply tube 21; and a suction pump 25 connected to the ink discharge tube 22.

[0024] The pressure pump 24 pressurizes the ink supply tube 21 and delivers the ink to the inkjet head 5 through the ink supply tube 21. As a result, the ink supply tube 21 side has a positive pressure relative to the inkjet head 5. The suction pump 25 depressurizes the ink discharge tube 22, thereby sucking ink from the inkjet head 5 through the ink discharge tube 22. This creates a negative pressure on the ink discharge tube 22 side relative to the inkjet head 5. By driving the pressure pump 24 and the suction pump 25, ink circulates between the inkjet head 5 and the ink tank 4 through the circulation path 23.

[0025] The scanning mechanism 7 reciprocates and scans the inkjet head 5 in the Y direction. The scanning mechanism 7 includes a guide rail 28 extending in the Y direction and a carriage 29 movably supported by the guide rail 28 .

[0026] <Inkjet Head 5> like Figure 1 As shown, the inkjet head 5 is mounted on the carriage 29. In the example shown in the figure, a plurality of inkjet heads 5 are mounted on one carriage 29 in parallel along the Y direction. The inkjet head 5 includes: a head chip 50 (see Figure 3 an ink supply portion (not shown) that connects the ink circulation mechanism 6 and the head chip 50; and a control portion (not shown) that applies a driving voltage to the head chip 50.

[0027] <Head chip 50> Figure 3 It is an exploded perspective view of the head chip 50 . Figure 4 It is along Figure 3 Cross-sectional view along line IV-IV. Figure 5 It is along Figure 3 Cross-sectional view of line VV. like Figures 3 to 5As shown, the head chip 50 is a so-called edge-shooting type head chip that discharges ink from the distal end of a discharge channel 71 in the channel extension direction (Z direction) and circulates ink between the head chip and the ink tank 4 .

[0028] The head chip 50 includes a first chip module 51A, a second chip module 51B, a return plate 52, and a nozzle plate 53. In the following description, the configurations of the chip modules 51A and 51B are described using the first chip module 51A as an example. Therefore, components of the second chip module 51B that are identical to those of the first chip module 51A are sometimes assigned the same reference numerals as those of the first chip module 51A, and their descriptions are omitted.

[0029] <First Chip Module 51A> The first chip module 51A includes a first actuator plate 61, a first cover plate 62, and a first back plate 63. In the following description, the first chip module 51A is described with the +Y side being the front side and the -Y side being the back side.

[0030] The first actuator plate 61 is a laminated substrate (so-called herringbone type) formed by laminating two piezoelectric substrates whose polarization directions differ in the thickness direction (Y direction (second direction)). A ceramic substrate made of, for example, PZT (lead zirconate titanate) is preferably used as the piezoelectric substrate. However, the first actuator plate 61 may also be formed from a single piezoelectric substrate with a single polarization direction (so-called unipolar type).

[0031] The first actuator plate 61 is formed with ejection channels (ejection channels) 71 filled with ink and non-ejection channels 72 not filled with ink. The channels 71 and 72 are alternately arranged on the first actuator plate 61 at intervals along the X direction (first direction) to form a channel array 70. In this embodiment, the channel extension direction coincides with the Z direction (extension direction), but the channel extension direction may also intersect the Z direction.

[0032] like Figure 3 、 Figure 4 As shown, the discharge channel 71 has an upper end that terminates within the first actuator plate 61, and a lower end that opens at the lower end surface of the first actuator plate 61. Meanwhile, the upper portion of the discharge channel 71 gradually decreases in depth in the Y direction as it moves upward. The lower portion of the discharge channel 71 penetrates the first actuator plate 61 in the Y direction. like Figure 3 、 Figure 5 As shown, the non-ejection channel 72 penetrates the first actuator plate 61 in the Z direction. The non-ejection channel 72 penetrates the first actuator plate 61 in the Y direction over its entire length in the Z direction. That is, the depth of the non-ejection channel 72 in the Y direction is the same over its entire length in the Z direction.

[0033] The portion of the first actuator plate 61 located between the discharge channel 71 and the non-discharge channel 72 constitutes a drive wall 75. Thus, the discharge channel 71 is surrounded on both sides in the X direction by a pair of drive walls 75. The portion of the first actuator plate 61 located above the discharge channel 71 constitutes a tail portion 76.

[0034] <First Cover Plate 62> like Figures 3 to 5 As shown, the first cover plate 62 is bonded to the surface of the first actuator plate 61. Specifically, the first cover plate 62 closes the surface-side openings of the channels 71 and 72 while exposing the surface of the tail portion 76. The lower end surface of the first cover plate 62 is arranged coplanar with the lower end surface of the first actuator plate 61.

[0035] A common ink chamber 80 is formed in the first cover plate 62 at a position that overlaps the upper portion of the discharge channel 71 when viewed from the Y direction. The common ink chamber 80 extends in the X direction, for example, by a length that spans the channel array 70, and opens on the surface of the first cover plate 62. The common ink chamber 80 is indirectly connected to the ink supply tube 21 via an inlet port (not shown). The common ink chamber 80 has slits 81 formed at positions that overlap with the upper portions of the ejection channels 71 when viewed from the Y direction. The slits 81 connect the interior of the ejection channels 71 with the interior of the common ink chamber 80 through the upper portions of the ejection channels 71. Therefore, the common ink chamber 80 communicates with the ejection channels 71 through the slits 81, but is not connected to the non-ejection channels 72.

[0036] <First Back Plate 63> The first back plate 63 is joined to the back surface of the first actuator plate 61. The first back plate 63 has the same outer shape as the first actuator plate 61 when viewed from the Y direction. The first back plate 63 entirely overlaps the first actuator plate 61 when viewed from the Y direction. In other words, the first back plate 63 closes the back surface openings of the channels 71 and 72.

[0037] like Figure 3 As shown, the first actuator plate 61 has common wiring 85 and individual wiring 86 as drive wiring formed thereon. like Figure 3 、 Figure 4 As shown, the common wiring 85 includes a common electrode 87 and a common terminal 88 . The common electrode 87 is formed on the inner side surfaces of the ejection channel 71 that face each other in the X direction. In the illustrated example, the common electrode 87 is formed over the entire area of ​​the inner side surface of the ejection channel 71 in the Y and Z directions. Furthermore, the common electrode 87 only needs to be formed on the inner side surface of the ejection channel 71 at least in a portion below the lower opening edge of the slit 81.

[0038] like Figure 4 As shown, the common electrode 87 according to the first embodiment is formed by a front-side common portion 87a and a back-side common portion 87b extending over the entire Y-direction area of ​​the inner surface of the ejection channel 71. Specifically, the front-side common portion 87a constitutes the front-side region of the common electrode 87. Specifically, the +Y-side edge of the front-side common portion 87a coincides with the front-side opening edge of the ejection channel 71. The -Y-side edge of the front-side common portion 87a is located on the -Y side relative to the Y-direction center of the inner surface of the ejection channel 71. The back-side common portion 87b constitutes the back-side region of the common electrode 87. Specifically, the -Y-side edge of the back-side common portion 87b coincides with the back-side opening edge of the ejection channel 71. The +Y-side edge of the back-side common portion 87b is located on the +Y side relative to the Y-direction center of the inner surface of the ejection channel 71. In other words, a portion of the back-side common portion 87b, including the Y-direction center of the inner surface of the ejection channel 71, overlaps with the front-side common portion 87a.

[0039] like Figure 3 As shown, common terminals 88 are formed on the surface of the tail portion 76. Common terminals 88 are provided on the surface of the tail portion 76 corresponding to each discharge channel 71. Each common terminal 88 extends linearly along the Z direction above the corresponding discharge channel 71. The lower end of the common terminal 88 is connected to the common electrode 87 at the upper opening edge of the discharge channel 71.

[0040] like Figure 3 、 Figure 5 As shown, the individual wiring 86 includes an individual electrode 91 , an individual terminal 92 , a routing wiring 93 , and a bypass wiring 94 . The individual electrodes 91 are formed on the lower portion of the inner side surfaces of the non-ejection channels 72 that face each other in the X direction. Specifically, the lower edge of the individual electrode 91 coincides with the lower opening edge of the non-ejection channel 72. The upper edge of the individual electrode 91 is located within the height range of the common ink chamber 80. That is, at least a portion of the individual electrode 91 faces the common electrode 87 in the X direction, sandwiching the drive wall 75. In the illustrated example, the individual electrode 91 is formed over the entire length in the Z direction and over the entire area in the Y direction of the non-ejection channel 72. In addition, the individual electrode 91 only needs to be formed in a portion that is at least lower than the lower opening edge of the slit 81.

[0041] like Figure 5As shown, the individual electrode 91 according to the first embodiment is formed by a front-side individual portion 91a and a back-side individual portion 91b extending over the entire Y-direction area of ​​the inner surface of the non-ejection channel 72. Specifically, the front-side individual portion 91a constitutes the front-side region of the individual electrode 91. Specifically, the +Y-side edge of the front-side individual portion 91a coincides with the front-side opening edge of the non-ejection channel 72. The -Y-side edge of the front-side individual portion 91a is located on the -Y side relative to the Y-direction center of the inner surface of the non-ejection channel 72. The back-side separate portion 91b constitutes the back-side region of the separate electrode 91. Specifically, the -Y-side edge of the back-side separate portion 91b coincides with the back-side opening edge of the non-ejection channel 72. The +Y-side edge of the back-side separate portion 91b is located on the +Y side relative to the Y-direction center of the inner surface of the non-ejection channel 72. In other words, a portion of the back-side separate portion 91b, including the Y-direction center of the inner surface of the non-ejection channel 72, overlaps with the front-side separate portion 91a.

[0042] The individual terminal 92 is formed on the surface of the tail portion 76 in a portion located above the common terminal 88. The individual terminal 92 is formed in a strip shape extending in the X direction. The individual terminal 92 reaches the surface side opening edge of the non-discharge channel 72 that is opposite to the discharge channel 71 in the X direction. In the tail portion 76, a dividing groove 79 is formed in a portion located between the common terminal 88 and the individual terminal 92. The dividing groove 79 is open on the surface of the tail portion 76 and extends in the X direction. The dividing groove 79 separates the common terminal 88 from the individual terminal 92. The depth of the dividing groove 79 in the Y direction is formed to be less than half of the thickness of the first actuator plate 61. However, the depth of the dividing groove 79 can be appropriately changed.

[0043] The routing wiring 93 is a wiring that connects the individual electrodes 91 and the individual terminals 92. The routing wiring 93 includes a first wiring portion 95 and a second wiring portion 96. The first wiring portion 95 is the wiring that forms the base of the routing wiring 93. The first wiring portion 95 extends upward from the individual electrode 91 on the inner side surface of the non-ejection channel 72. The first wiring portion 95 extends over the entire length of the non-ejection channel 72, located above the common electrode 87, on the inner side surface. Specifically, the first wiring portion 95 includes a first region 95a, a second region 95b, and a third region 95c.

[0044] The first region 95a is a portion located between the individual electrode 91 and the dividing groove 79 on the inner side of the non-ejection channel 72. The first region 95a extends in the Z direction with a uniform width along the Y direction. The width of the first region 95a in the Y direction is formed to be less than the thickness of the first actuator plate 61. In the example shown in the figure, the first region 95a is formed to have the same width as the surface-side individual portion 91a. Specifically, the surface-side end edge of the first region 95a reaches the surface-side opening edge of the non-ejection channel 72. The back-side end edge of the first region 95a is located closer to the -Y side than the center of the non-ejection channel 72 in the Y direction.

[0045] The second region 95b extends upward from the first region 95a. The second region 95b is the portion of the inner surface of the non-ejection channel 72 that is located within the height range of the dividing groove 79. In other words, the portion of the second region 95b on the inner surface of the non-ejection channel 72 that is located on the -Y side relative to the dividing groove 79 extends along the Z direction over the entire length of the dividing groove 79. The width of the second region 95b in the Y direction is uniform across its entire length in the Z direction. Specifically, the front edge of the second region 95b reaches the back edge of the dividing groove 79. The back edge of the second region 95b is positioned at the same position in the Y direction as the back edge of the first region 95a. In other words, the width of the second region 95b in the Y direction is narrower than that of the first region 95a by the depth of the dividing groove 79.

[0046] The third region 95c extends upward from the second region 95b. The third region 95c extends along the Z direction at a portion located above the dividing groove 79 on the inner side surface of the non-ejection channel 72. The upper end edge of the third region 95c reaches the upper end opening edge of the non-ejection channel 72. The width of the third region 95c in the Y direction is the same as that of the first region 95a. That is, the surface side end edge of the third region 95c reaches the surface side opening edge of the non-ejection channel 72. The back side end edge of the third region 95c is located closer to the -Y side than the center of the non-ejection channel 72 in the Y direction. The above-mentioned separate terminal 92 connects the third regions 95c of the routing wiring 93 that are facing each other in the X direction with the ejection channel 71 sandwiched between them at the surface side opening edge of the non-ejection channel 72.

[0047] Figure 6 is with Figure 5 The cross-sectional view corresponding to the VI-VI line. Figure 7 is with Figure 5 The cross-sectional view corresponding to line VII-VII. like Figure 6 、 Figure 7As shown, the thickness of the routing wire 93 in the X direction (the dimension perpendicular to the inner surface of the non-discharge channel 72) is uniform throughout the entire wiring. Therefore, the cross-sectional area of ​​the routing wire 93 perpendicular to the Z direction is smallest in the second region 95b. In other words, the resistance of the routing wire 93 in the second region 95b is greater than that in the first region 95a and the third region 95c.

[0048] like Figure 5 、 Figure 7 As shown, the second wiring portion 96 is formed in addition to the first wiring portion 95. The second wiring portion 96 is formed on the inner side surface of the non-discharge channel 72 so as to be connected to at least the second region 95b. In the Z direction, the second wiring portion 96 encompasses the entire second region 95b and is formed so as to span the boundary between the first region 95a and the second region 95b, as well as the boundary between the third region 95c and the second region 95b. In other words, the second wiring portion 96 is provided only on the portion of the routing wiring 93 that includes the second region 95b.

[0049] In the Y direction, the second wiring portion 96 overlaps with a portion of the first wiring portion 95 (the second region 95b) and protrudes toward the -Y side relative to the second region 95b. Specifically, the surface side end of the second wiring portion 96 overlaps with the back side end of the second region 95b when viewed from the X direction. The back side end edge of the second wiring portion 96 reaches the back side opening edge of the non-ejection channel 72. That is, the portion of the lead wiring 93 located within the height range of the dividing groove 79 is formed in the entire area of ​​the Y direction relative to the inner side surface of the non-ejection channel 72 using the second region 95b and the second wiring portion 96. In addition, considering the deviation in the evaporation depth, the overlap amount between the back side end of the second region 95b and the surface side end of the second wiring portion 96 is preferably, for example, greater than 10 μm. In this way, the reliability of the conduction between the back side end of the second region 95b and the surface side end of the second wiring portion 96 can be ensured.

[0050] In this manner, the second wiring portion 96 overlaps a portion of the first wiring portion 95, forming the routing wiring 93 according to the first embodiment. In this case, the cross-sectional area of ​​the routing wiring 93 in a direction perpendicular to the Z direction is set so that it is larger than the cross-sectional area of ​​the second region 95b alone at any point in the Z direction. In other words, the resistance of the routing wiring 93 is lower than the resistance of the second region 95b alone at any point in the Z direction.

[0051] A bypass wiring 94 is formed on the back surface of the actuator plate 61 in a portion facing the dividing groove 79 in the Y direction. The bypass wiring 94 is formed in a strip shape extending in the X direction. The bypass wiring 94 reaches the back side opening edge of the non-discharge channel 72 that sandwiches the discharge channel 71 and faces each other in the X direction. The bypass wiring 94 connects the second wiring portions 96 that sandwich the discharge channel 71 and face each other in the X direction.

[0052] A flexible printed circuit board (not shown) serving as external wiring is crimped onto the surface of the tail portion 76. The flexible printed circuit board is connected to the common terminal 88 and the individual terminal 92 on the surface of the tail portion 76. The flexible printed circuit board connects the first chip module 51A and the control unit.

[0053] <Second Chip Module 51B> The second chip module 51B includes a second actuator plate 101, a second cover plate 102, and a second back plate 103. The second back plate 103, the second actuator plate 101, and the second cover plate 102 are stacked in this order from the +Y side to the -Y side. The second chip module 51B is stacked on the first chip module 51A with its front side (-Y side) facing the side opposite to the first chip module 51A. Specifically, the first chip module 51A and the second chip module 51B are integrated by bonding the back surfaces of the first back plate 63 and the second back plate 103 to each other. In this case, the lower end surfaces of the chip modules 51A and 51B are arranged coplanar.

[0054] The ejection channels 71 and non-ejection channels 72 of the second chip module 51B are arranged at a half-pitch offset from the arrangement pitch of the ejection channels 71 and non-ejection channels 72 of the first chip module 51A. That is, the ejection channels 71 and non-ejection channels 72 of each chip module 51A and 51B are arranged in a staggered pattern. In this case, the ejection channels 71 of the first chip module 51A and the non-ejection channels 72 of the second chip module 51B face each other in the Y direction, and the non-ejection channels 72 of the first chip module 51A and the ejection channels 71 of the second chip module 51B face each other in the Y direction. Furthermore, the spacing between the channels 71 and 72 of each chip module 51A and 51B can be appropriately changed.

[0055] <Return to Plate 52> The return plate 52 is collectively bonded to the lower end surfaces of each chip module 51A, 51B via an adhesive. The return plate 52 closes the lower end openings of each channel 71, 72. The return plate 52 is formed of, for example, polyimide. Multiple first communication paths 110 and multiple second communication paths 111 are formed on the return plate 52.

[0056] Figure 8 is with Figure 4 The cross-sectional view corresponding to the line VIII-VIII. Figure 9 yes Figure 4 Magnified view of part IX. like Figure 8 、 Figure 9 As shown, a plurality of first communication passages 110 are respectively formed in the first chip module 51A at positions equivalent to those of the ejection channels 71 in the X direction. In the present embodiment, a plurality of first communication passages 110 are formed at intervals along the X direction corresponding to the arrangement pitch of the ejection channels 71. When viewed from the side in the X direction, each first communication passage 110 is formed in a U-shape. Specifically, each first communication passage 110 has an upstream opening 115, a downstream opening 116, and a connecting portion 117. All the first communication passages 110 have the same structure, and therefore, in the following structure, the details of the first communication passage 110 will be described by taking one first communication passage 110 as an example.

[0057] The upstream opening 115 is formed at a position that overlaps with the discharge channel 71 when viewed from above. The upper end of the upstream opening 115 opens to the upper surface of the return plate 52, and the lower end terminates inside the return plate 52. The upstream opening 115 communicates with the discharge channel 71 through the lower end opening of the discharge channel 71. In the first embodiment, the flow path cross-sectional area (cross-sectional area perpendicular to the Z direction) of the upstream opening 115 is the same throughout the entire Z direction. However, the flow path cross-sectional area of ​​the upstream opening 115 may also vary according to the position in the Z direction.

[0058] At least a portion of the opening edge of the upstream opening 115 is positioned outward from the lower opening edge of the discharge channel 71 when viewed from above. Specifically, the X-direction dimension of the upstream opening 115 is smaller than the X-direction dimension of the lower opening of the discharge channel 71. The Y-direction dimension of the upstream opening 115 is larger than the Y-direction dimension of the lower opening of the discharge channel 71. Portions of the lower end surface of the first chip module 51A located on both sides of the discharge channel 71 in the Y-direction are exposed through the upstream opening 115.

[0059] The downstream opening 116 is formed at a position that overlaps with the first back plate 63 when viewed from above. The upper end of the downstream opening 116 opens on the upper surface of the return plate 52, and the lower end terminates within the return plate 52. The size of the downstream opening 116 in the Z direction is the same as that of the upstream opening 115. In this embodiment, the flow path cross-sectional area of ​​the downstream opening 116 (the cross-sectional area perpendicular to the Z direction) is the same throughout the entire Z direction. However, the flow path cross-sectional area of ​​the downstream opening 116 may also vary according to the position in the Z direction.

[0060] The connecting portion 117 connects the upstream opening 115 and the downstream opening 116. The connecting portion 117 opens only on the lower surface of the return plate 52 and extends in the Y direction. The Z-direction dimension of the connecting portion 117 is uniform throughout the entire area in the Y direction. In this embodiment, the Z-direction dimension of the connecting portion 117 is larger than the Z-direction dimensions of the upstream opening 115 and the downstream opening 116. However, the Z-direction dimension of the connecting portion 117 may vary depending on the position in the Y direction.

[0061] In a plan view, the dimension of the connection portion 117 in the X direction is larger than that of the upstream opening 115 and the downstream opening 116. Specifically, the connection portion 117 includes an upstream wide portion 117a and a downstream wide portion 117b. The upstream wide portion 117a is arranged at a position overlapping the upstream opening 115 in a plan view. The upstream wide portion 117a is slightly larger than the upstream opening 115 in a plan view. The upstream opening 115 opens on the downwardly facing surface (bottom surface) of the inner surface of the upstream wide portion 117a. Downstream wide portion 117b extends from upstream wide portion 117a toward the -Y side. When viewed from above, downstream wide portion 117b overlaps with downstream opening 116. When viewed from above, downstream wide portion 117b is slightly larger than downstream opening 116. The X-direction dimension of downstream wide portion 117b is smaller than that of upstream wide portion 117a. Downstream opening 116 opens onto the bottom surface of downstream wide portion 117b.

[0062] like Figure 5 As shown, a plurality of second communication passages 111 are formed in the second chip module 51B at positions equivalent to those of the ejection channels 71 in the X direction. In this embodiment, a plurality of second communication passages 111 are formed at intervals along the X direction corresponding to the arrangement pitch of the ejection channels 71 of the second chip module 51B. That is, the first communication passage 110 and the second communication passage 111 are alternately arranged at intervals along the X direction. In addition, the second communication passage 111 has the same structure as the first communication passage 110. Therefore, the same reference numerals are assigned to the same components of the second communication passage 111 as the first communication passage 110, and a detailed description of the second communication passage 111 is omitted.

[0063] Figure 10 is with Figure 4 The cross-sectional view corresponding to line XX. like Figure 4 、 Figure 10 As shown, the first back plate 63 and the second back plate 103 are stacked to form a flow channel plate 120. The flow channel plate 120 has a plurality of first connection paths 121, a plurality of second connection paths 122, and a manifold 123 formed therein.

[0064] The plurality of first connecting passages 121 are formed at positions that overlap with the downstream openings 116 of the first connecting passages 110 when viewed from above. The first connecting passages 121 are arranged at intervals along the X direction at the same pitch as the first connecting passages 110. Specifically, the first connecting passages 121 open on the back surface of the first back plate 63. The back surface openings of the first connecting passages 121 are blocked by the second back plate 103.

[0065] The first connecting passage 121 extends linearly in the Z direction when viewed from the Y direction. The lower end of the first connecting passage 121 opens onto the lower end surface of the first back plate 63. Thus, the lower end opening of the first connecting passage 121 communicates with the downstream opening 116. Meanwhile, the upper end of the first connecting passage 121 terminates within the first back plate 63.

[0066] like Figure 8 As shown, the X-direction dimension of the lower opening of first connecting passage 121 is larger than that of downstream opening 116 and smaller than that of downstream wide portion 117b. In this case, the opening edge of downstream opening 116 protrudes inward relative to the lower opening edge of first connecting passage 121. However, the X-direction dimension of the lower opening of first connecting passage 121 may also be larger than that of downstream wide portion 117b or smaller than that of downstream opening 116.

[0067] like Figure 10 As shown, the plurality of second connecting passages 122 are formed at positions that overlap with the downstream openings 116 of the respective second connecting passages 111 in a plan view. The second connecting passages 122 are arranged at intervals along the X direction at the same pitch as the second connecting passages 111. In other words, the first connecting passages 121 and the second connecting passages 122 are arranged alternately along the X direction.

[0068] like Figure 5 、 Figure 8 As shown, each second connection path 122 is connected to the downstream opening 116 of the corresponding second connecting path 111. Specifically, the second connection path 122 opens on the back side of the second back plate 103 (the surface facing the +Y side). The back side opening of the second connection path 122 is blocked by the first back plate 63. The second connection path 122 extends along the Z direction. The lower end of the second connection path 122 opens on the lower end surface of the second back plate 103. Thus, the lower end opening of the second connection path 122 is connected to the downstream opening 116 of the second connecting path 111. On the other hand, the upper end of the second connection path 122 terminates inside the second back plate 103. In addition, the dimensions of the second connection path 122 can be set in the same way as the first connection path 121.

[0069] The manifold 123 is formed in the portion of the flow path plate 120 located above each of the connection paths 121 and 122. The manifold 123 is formed by overlapping the first recess 123a formed on the first back plate 63 with the second recess 123b formed on the second back plate 103. The first recess 123a is a recess that opens on the back surface of the first back plate 63 and extends in the Z direction and the Y direction. The second recess 123b is a recess that opens on the back surface of the second back plate 103 and extends in the Z direction and the Y direction. The manifold 123 is formed by interconnecting the back side openings of the first recess 123a and the second recess 123b. In addition, the manifold 123 can also be a structure in which the recess formed only on one of the first back plate 63 and the second back plate 103 is blocked by the back surface of the other back plate.

[0070] Each connection path 121 and 122 is collectively connected to the manifold 123. Specifically, the upper end of each first connection path 121 opens onto the lower end surface of the first recess 123a. The upper end of each second connection path 122 opens onto the lower end surface of the second recess 123b. Furthermore, the manifold 123 is indirectly connected to the ink discharge tube 22 via an outlet port (not shown).

[0071] The chip modules 51A, 51B and the return plate 52 are covered with a protective film 125. In this embodiment, the protective film 125 is also formed on the inner surface of the common ink chamber 80, the inner surface of the slit 81, the inner surface of the discharge channel 71, the inner surface of each connecting path 110, 111, the inner surface of each connecting path 121, 122, and the inner surface of the manifold 123. As an insulating material, the protective film 125 includes, for example, an organic insulating material such as a paraxylene resin material (for example, Parylene (registered trademark)). The protective film 125 can also be composed of tantalum oxide (Ta2O5), silicon nitride (SiN), silicon carbide (SiC), silicon oxide (SiO2), or diamond-like carbon, or can include at least any one of them.

[0072] <Nozzle Plate 53> like Figures 3 to 5 As shown, the nozzle plate 53 is joined to the lower end surface of the return plate 52. The nozzle plate 53 has a plurality of nozzle holes (first nozzle holes 131 and second nozzle holes 132) arranged therein, penetrating the nozzle plate 53 in the Z direction.

[0073] A plurality of first nozzle holes 131 are formed in the nozzle plate 53 at positions that overlap with the first communication passages 110 when viewed from above. That is, the first nozzle holes 131 are arranged at intervals along the X direction at the same pitch as the first communication passages 110. The first nozzle holes 131 are connected to the corresponding ejection channel 71 of the first chip module 51A through the corresponding first communication passage 110. Specifically, each first nozzle hole 131 is formed at a position at the +Y side end of each first communication passage 110 that overlaps with the ejection channel 71 and the upstream wide portion 117a when viewed from above. In addition, the first nozzle hole 131 may be connected to the first communication passage 110 at a position that is offset in the Y direction relative to the ejection channel 71 of the first chip module 51A.

[0074] A plurality of second nozzle holes 132 are formed in the nozzle plate 53 at positions that overlap with the second communication passages 111 when viewed from above. That is, the second nozzle holes 132 are arranged at intervals along the X direction at the same pitch as the second communication passages 111. The second nozzle holes 132 are connected to the corresponding ejection channel 71 of the second chip module 51B through the corresponding second communication passage 111. Specifically, each second nozzle hole 132 is formed at a position at the -Y side end of each second communication passage 111 that overlaps with the ejection channel 71 and the upstream wide portion 117a when viewed from above. In addition, the second nozzle hole 132 may also be connected to the second communication passage 111 at a position that is offset in the Y direction relative to the ejection channel 71 of the second chip module 51B.

[0075] [Operation Method of Printer 1] Next, a description will be given of a case where characters, graphics, etc. are recorded on a recording medium P using the printer 1 configured as described above. In addition, as the initial state, Figure 1 The four ink tanks 4 shown are each sufficiently filled with inks of different colors. In addition, the inks in the ink tanks 4 are filled into the inkjet head 5 via the ink circulation mechanism 6.

[0076] When the printer 1 is operated in this initial state, the recording medium P is sandwiched between the rollers 11 and 12 and simultaneously conveyed toward the +X side. Simultaneously with the conveyance of the recording medium P, the carriage 29 moves in the Y direction, causing the inkjet head 5 mounted on the carriage 29 to reciprocate in the Y direction.

[0077] Here, the movement of each inkjet head 5 will be described in detail below. In the vertical circulation type head chip 50 as in this embodiment, first, Figure 2The pressure pump 24 and the suction pump 25 shown are operated to circulate ink in the circulation path 23. In this case, the ink circulating in the ink supply pipe 21 flows into the common ink chamber 80 of each chip module 51 through the inlet port. The ink flowing into each common ink chamber 80 is supplied to each ejection channel 71 through the slit 81. The ink flowing into each ejection channel 71 is collected in the manifold 123 through each communication path 110, 111 and each connection path 121, 122, and then discharged to the ink discharge pipe 22 through the outlet port. The ink discharged to the ink discharge pipe 22 returns to the ink tank 4 and is then supplied to the ink supply pipe 21 again. In this way, the ink circulates between the inkjet head 5 and the ink tank 4.

[0078] Then, if the reciprocating movement is started by the slide 29, the driving voltage is applied to the electrodes 87 and 91 via the flexible substrate. At this time, the driving voltage is applied between the electrodes 87 and 91 with the individual electrode 91 as the driving potential Vdd and the common electrode 87 as the reference potential GND. As a result, thickness slip deformation occurs in the two driving walls 75 that define the ejection channel 71, and the two driving walls 75 are deformed in a manner that protrudes toward the non-ejection channel 72 side. That is, the actuator plates 61 and 101 of this embodiment are stacked with two piezoelectric substrates that are polarized in the thickness direction (Y direction), so that by applying the driving voltage, they are bent and deformed in a V-shape with the middle position of the driving wall 75 in the Y direction as the center. As a result, the ejection channel 71 is deformed in a manner that seems to bulge.

[0079] When the volume of the ejection channel 71 increases due to the deformation of the two drive walls 75, the ink in the common ink chamber 80 is guided into the ejection channel 71 through the slit 81. The ink guided into the ejection channel 71 then becomes a pressure wave and propagates within the ejection channel 71. When the pressure wave reaches the nozzle holes 131 and 132, the drive voltage applied between the electrodes 87 and 91 is reduced to zero. As a result, the driving wall 75 is restored, and the volume of the temporarily enlarged discharge channel 71 is restored to its original volume. Through this action, the pressure inside the discharge channel 71 increases, and the ink is pressurized. As a result, the ink can be discharged from the nozzle holes 131 and 132. At this time, when the ink passes through the nozzle holes 131 and 132, it becomes droplet-shaped ink droplets and is discharged. As a result, text or images can be recorded on the recording medium P as described above. That is, in the head chip 50 of this embodiment, a portion of the ink flowing in each connecting path 110 and 111 is discharged through the nozzle holes 131 and 132, and on the other hand, the remaining ink returns to the manifold 123 through the connecting paths 121 and 122.

[0080] [Manufacturing Method of Head Chip 50] Next, a method for manufacturing the above-mentioned head chip 50 will be described. Figure 11 This is a flowchart for explaining a method of manufacturing the head chip 50 . Figures 12 to 25 5 is a process diagram for explaining a method of manufacturing the head chip 50. In this case, Figures 12 to 21 in Figures 12 to 14 、 Figures 17 to 19 is with Figure 10 The corresponding cross-sectional view, Figure 15 、 Figure 16 、 Figure 20 is with Figure 7 The corresponding cross-sectional view, Figure 21 is with Figure 6 Corresponding cross-sectional view. Figures 12 to 21 in Figures 23 to 25 is with Figure 4 In the following description, for the sake of convenience, the case where the head chip 50 is manufactured at the chip level will be described as an example.

[0081] like Figure 11 As shown, the head chip 50 includes a module manufacturing step S1 , a module laminating step S2 , a return plate laminating step S3 , a return plate processing step S4 , a protective film forming step S5 , and a nozzle plate laminating step S6 .

[0082] The module manufacturing process S1 manufactures the first chip module 51A and the second chip module 51B. This process includes a surface patterning process S11, a channel forming process S12, a first wiring forming process S13, a dividing groove forming process S14, a cover plate laminating process S15, a grinding process S16, a second wiring forming process (drive wiring forming process) S17, a backplane laminating process S18, and a backplane processing process S19. All chip modules 51A and 51B are manufactured using the same method. Therefore, in the following description, the module manufacturing process S1 is described using the first chip module 51A as an example.

[0083] like Figure 12 As shown, in the surface patterning step S11, a mask pattern 200 is formed on the surface of the first actuator plate 61. Specifically, after forming a mask material (e.g., a resist film) on the surface of the first actuator plate 61, the mask material is patterned using photolithography. Mask openings are formed in the mask pattern 200, for example, in portions of the surface of the first actuator plate 61 corresponding to the areas where the common terminals 88 and the individual terminals 92 are formed.

[0084] like Figure 13As shown, in the channel forming step S12, the dicer is used to process the areas where the discharge channel 71 and the non-discharge channel 72 are to be formed in the first actuator plate 61. Furthermore, the amount of entry of the dicer in the Y direction is set such that after the channel forming step S12, neither the discharge channel 71 nor the non-discharge channel 72 penetrates the first actuator plate 61.

[0085] like Figure 14 As shown, in the first wiring forming step S13, oblique evaporation or the like is performed from the surface side of the first actuator plate 61. Specifically, an electrode material is formed on the surface of the first actuator plate 61 via the mask pattern 200. As a result, the common terminal 88 and the individual terminal 92 are formed on the surface of the first actuator plate 61.

[0086] In the first wiring forming process S13, the electrode material is introduced into each channel 71, 72 through the surface side opening of each channel 71, 72. As a result, a portion of the common electrode 87 (surface side common portion 87a) is formed on the inner surface of the ejection channel 71 from the surface side opening edge of the ejection channel 71 to a predetermined range in the Y direction. On the other hand, a portion of the individual electrode 91 (surface side individual portion 91a) is formed on the portion of the inner surface of the non-ejection channel 72 that faces the ejection channel 71 in the X direction from the surface side opening edge of the non-ejection channel 72 to a predetermined range in the Y direction. Figure 15 As shown, a portion of the routing wiring 93 (first wiring portion 95 ) is formed on a portion of the inner surface of the non-ejection channel 72 that is located closer to the +Z side than the individual electrode 91 .

[0087] like Figure 16 As shown, in the dividing groove forming step S14, a dividing groove 79 is formed in the portion of the tail portion 76 located between the common terminal 88 and the individual terminal 92. Specifically, the dicer is moved in the X direction relative to the portion of the surface of the first actuator plate 61 located between the common terminal 88 and the individual terminal 92. As a result, the portion of the routing wiring 93 located on the dicer's path is removed as the dividing groove 79 is processed. That is, on the inner side surface of the non-discharge channel 72, on the -Y side relative to the dividing groove 79, a second region 95b remains, which is narrower than the first region 95a and the third region 95c. Furthermore, after the dividing groove forming step S14, the mask pattern 200 is removed.

[0088] like Figure 17 As shown, in the cover plate laminating step S15 , the first cover plate 62 is attached to the surface of the first actuator plate 61 . like Figure 18As shown, in the grinding step S16 , the back surface of the first actuator plate 61 is ground. Specifically, the first actuator plate 61 is ground until the ejection channel 71 and the non-ejection channel 72 open on the back surface of the first actuator plate 61 .

[0089] like Figure 19 As shown, in the second wiring forming process S17, with the mask material 201 set on the back side of the first actuator plate 61, oblique evaporation is performed from the back side of the first actuator plate 61. The mask material 201 has a mask opening 201a in the portion of the back side of the first actuator plate 61 where the channel column 70 is formed when viewed from the Y direction. In the portion of each channel 71, 72 opened by the mask opening 201a, the electrode material is introduced through the back side opening of each channel 71, 72. As a result, a common electrode 87 (back side common portion 87b) is formed on the inner surface of the ejection channel 71 from the back side opening edge of the ejection channel 71 to a predetermined range in the Y direction. As a result, a common electrode 87 is formed on the inner side surface of the ejection channel 71 over the entire area in the Y direction.

[0090] In the second wiring forming step S17, the individual electrodes 91 (back-side individual portions 91b) are formed on the inner surface of the non-ejection channel 72, extending from the back-side opening edge of the non-ejection channel 72 to a predetermined range in the Y direction. As a result, the individual electrodes 91 are formed on the entire inner surface of the non-ejection channel 72 in the Y direction. In addition, if Figure 20 As shown, a portion of the routing wiring 93 (the second wiring portion 96) is formed on the inner surface of the non-ejection channel 72, which is located closer to the +Z side than the individual electrode 91. Specifically, the electrode material is introduced into the non-ejection channel 72 through the portion of the non-ejection channel 72 that is open through the mask opening 201a when viewed from the Y direction. As a result, the second wiring portion 96 is formed on the inner side surface of the non-ejection channel 72 in a manner connected to the second area 95b. In addition, the electrode material is also attached to the portion of the back surface of the actuator plate 61 that is exposed through the mask opening 201a. As a result, the bypass wiring 94 is formed on the portion of the back surface of the actuator plate 61 that is opposite to the dividing groove 79. In addition, the unnecessary electrode material attached to the portion of the back surface of the first actuator plate 61 that is exposed through the mask opening 201a is removed by laser processing or the like.

[0091] like Figure 21 As shown, the electrode material is not introduced into the portion of the non-ejection channel 72 covered by the mask material 201. Thus, the second wiring portion 96 is formed only in a portion of the routing wiring 93 including the second region 95b. Furthermore, the aforementioned dividing groove forming step S14 may be performed after the second wiring forming step S17.

[0092] like Figure 22 As shown, in the back plate laminating step S18 , the first back plate 63 is attached to the back surface of the first actuator plate 61 . In the backplane processing step S19, the first connection path 121 and the first recess 123a are formed on the first backplane 63. Thus, the first chip module 51A is completed. Furthermore, the second actuator plate 101 and the like are also processed through the same method as in the module manufacturing step S1 to manufacture the second chip module 51B.

[0093] like Figure 23 As shown, in the module stacking step S2, the chip modules 51A and 51B produced in the module production step S1 are bonded together. Specifically, with the lower end surfaces of the chip modules 51A and 51B aligned, the back surfaces of the back plates 63 and 103 are bonded together. As a result, the back opening of the first connecting path 121 is blocked by the second back plate 103, the back opening of the second connecting path 122 is blocked by the first back plate 63, and the manifold 123 is formed by the first recess 123a and the second recess 123b. This completes the stack of chip modules 51A and 51B.

[0094] like Figure 24 As shown, in the return plate laminating step S3 , the return plate 52 is bonded to the lower end surface of the laminated body of the chip modules 51A and 51B. like Figure 25 As shown, in the return plate processing step S4, connecting paths 110 and 111 are formed on the portion of the return plate 52 that overlaps with the discharge channel 71 when viewed from above. The connecting paths 110 and 111 are formed by subjecting the return plate 52 to, for example, laser processing. In addition, the return plate processing step S4 may be performed by etching or the like in addition to laser processing. In addition, in the present embodiment, the connecting paths 110 and 111 are formed after the return plate 52 is attached to the chip modules 51A and 51B, but the present invention is not limited to this configuration. The connecting paths 110 and 111 may also be formed in advance on the return plate 52 by laser processing or etching, and then attached to the chip modules 51A and 51B.

[0095] In the protective film forming step S5, a protective film 125 is formed on the inner surface of the common ink chamber 80, the inner surface of the slit 81, the inner surface of the ejection channel 71, the inner surface of each communication passage 110, 111, the inner surface of each connection passage 121, 122, and the inner surface of the manifold 123. The protective film 125 is formed by forming a film of a paraxylene-based resin material using a chemical vapor deposition method (CVD) or the like.

[0096] In the nozzle plate laminating step S6 , the nozzle plate 53 is bonded to the lower surface of the return plate 52 . The above steps complete the head chip 50. Furthermore, when manufacturing the head chip 50 at the wafer level, the actuator plate wafer, the cover plate wafer, and the backplane wafer undergo the same steps as in the module manufacturing step S1 to form a wafer stack. Subsequently, the wafer stack is singulated to remove the plurality of chip modules 51A and 51B. The chip modules 51A and 51B removed from the wafer stack are then subjected to the steps following the module stacking step S2 to complete the head chip 50.

[0097] Thus, the head chip 50 according to the first embodiment includes: an actuator plate (chip body) 61, 101 having an ejection channel (pressure chamber, ejection channel) 71 for storing ink and a drive wall (drive portion) 75 disposed in a portion facing the ejection channel 71; individual electrodes (drive electrodes) 91 formed on the drive wall 75; and routing wiring (drive wiring) 93 connecting the individual electrodes 91 to the flexible printed circuit board (external wiring). The routing wiring 93 is composed of: a first wiring portion 95 having a first region 95a and a second region 95b having a smaller cross-sectional area than the first region 95a, as measured perpendicular to the extending direction (Z direction) of the routing wiring 93; and a second wiring portion 96 connected to at least the second region 95b. According to this configuration, the second wiring portion 96 of the routing wiring 93 is formed so as to be connected to at least the second region 95b of the first wiring portion 95, which has a smaller cross-sectional area than the first region 95a. This reduces the maximum resistance of the routing wiring 93 as a whole. This prevents the routing wiring 93 from breaking, even when an unexpectedly large current flows through the routing wiring 93. Consequently, a head chip 50 with excellent long-term reliability can be provided.

[0098] In the head chip 50 according to the first embodiment, the second wiring portion 96 is provided only in a portion of the routing wiring 93 including the second region 95 b . According to this configuration, by providing the second wiring portion 96 only in a portion of the routing wiring 93 including the second area 95b, the increase in material cost of the routing wiring 93 associated with the addition of the second wiring portion 96 can be suppressed compared to the case where the second wiring portion 96 is formed in a manner covering the entire first wiring portion 95.

[0099] In the head chip 50 according to the first embodiment, the second wiring portion 96 is configured to be integrally connected to at least the second region 95b in the Y direction (second direction) along the inner surface of the non-ejection channel 72 (film formation surface of the drive wiring) in a plan view. According to this configuration, the second wiring portion 96 is connected to the second region 95b in a direction along the inner surface of the non-ejection channel 72, thereby further reducing the risk of disconnection, etc. In particular, by ensuring the width of the routing wiring 93 as in the head chip 50 according to the first embodiment, the risk of film formation defects due to the adhesion of foreign matter can be reduced compared to the case where the thickness of the routing wiring 93 is ensured while maintaining the same cross-sectional area.

[0100] The head chip 50 involved in the first embodiment is constructed as follows: an ejection channel (pressure chamber, ejection channel) 71 and a non-ejection channel (non-ejection channel) 72 are formed on the actuator plates 61 and 101, and the driving electrode includes a common electrode 87 formed on the inner side surface of the ejection channel 71 over the entire area in the Y direction and a separate electrode 91 formed on the inner side surface of the non-ejection channel 72 over the entire area in the Y direction, and a routing wiring 93 is connected to the separate electrode 91 on the inner side surface of the non-ejection channel 72. According to this configuration, on actuator plates 61 and 101, which are composed of two piezoelectric substrates with different polarization directions, it is necessary to form individual electrodes 91 over the entire area in the Y direction on the inner side surface of non-ejection channel 72. Therefore, by forming routing wiring 93 on the inner side surface of non-ejection channel 72, when forming individual electrodes 91 (back-side individual portion 91b), routing wiring 93 can be expanded in the Y direction via second wiring portion 96. This eliminates the need for a separate wiring formation step for forming second wiring portion 96, thereby minimizing the decrease in manufacturing efficiency associated with forming second wiring portion 96.

[0101] The head chip 50 involved in the first embodiment is constructed as follows: a dividing groove 79 is formed on the surface of the actuator plate 61, 101 to separate the common terminal 88 and the individual terminal 92, and the second area 95b is located on the inner side surface of the non-ejection channel 72 and overlaps with the dividing groove 79 in the Z direction. According to this configuration, the second wiring portion 96 is formed in the portion overlapping the dividing groove 79 in the Z direction, thereby suppressing short circuits between the common terminal 88 and the individual terminal 92 and reducing the maximum resistance value of the entire routing wiring 93 .

[0102] The inkjet head 5 and the printer 1 according to the first embodiment include the head chip 50 described above, and thus it is possible to provide the inkjet head 5 and the printer 1 with excellent reliability.

[0103] (Second embodiment) Figure 26 The head chip 50 and the Figure 5 Corresponding cross-sectional view. Figure 27 The head chip 50 and the Figure 7Cross-sectional view of the corresponding part. like Figure 26 、 Figure 27 As shown, in the Z direction, similar to the first embodiment, the second wiring portion 96 encompasses the entire second region 95b and is formed so as to straddle the boundary between the first region 95a and the second region 95b, and the boundary between the third region 95c and the second region 95b. Meanwhile, in the Y direction, the entire second wiring portion 96 is arranged to overlap with the first wiring portion 95. Therefore, the thickness of the routing wiring 93 in the area where the first and second wiring portions 95, 96 overlap is increased relative to the area where only the first wiring portion 95 is formed. In this case, the cross-sectional area of ​​the routing wiring 93 in a direction perpendicular to the Z direction is set so that it is larger than the cross-sectional area of ​​the second region 95b alone at any point in the Z direction. In other words, the resistance of the routing wiring 93 is lower than the resistance of the second region 95b alone at any point in the Z direction.

[0104] The second wiring portion 96 can be formed by, for example, providing a mask material with only an opening in the formation area of ​​the second wiring portion 96 on the surface of the actuator plates 61 and 101 after the first wiring formation step S13, and performing oblique vapor deposition again from the surface side of the actuator plates 61 and 101.

[0105] In the head chip 50 according to the second embodiment, the second wiring portion 96 is provided to cover at least the second region 95 b in the X direction perpendicular to the inner side surface (film formation surface) of the non-ejection channel 72 in a plan view. According to this configuration, by providing the second wiring portion 96 so as to cover the second region 95b, it is possible to suppress the increase in the size of the routing wiring 93 in the Y direction (the direction along the film formation surface) associated with the addition of the second wiring portion 96. Thus, while suppressing an increase in electrostatic capacitance, the maximum resistance value of the entire routing wiring 93 can be reduced.

[0106] In addition, you can also Figure 28 、 Figure 29 As shown in the second wiring portion 96 , a portion of the second wiring portion 96 overlaps the entire first wiring portion 95 in the Y direction, and the remaining second wiring portion 96 protrudes toward the −Y side relative to the first wiring portion 95 .

[0107] (Other Modifications) In addition, the technical scope of the present disclosure is not limited to the above-mentioned embodiment, and various modifications can be added without departing from the spirit of the present disclosure. For example, in the above embodiment, the inkjet printer 1 is described as an example of a liquid jet recording apparatus, but the apparatus is not limited to a printer and may be a facsimile machine or a print-on-demand printer. In the above embodiment, an example is described in which the inkjet head moves relative to the recording medium during printing (so-called a shuttle), but the present invention is not limited to this configuration. The configuration involved in the present disclosure can also be adopted in a configuration in which the recording medium is moved relative to the inkjet head while the inkjet head is fixed (so-called a fixed-head machine). In the above embodiment, the recording medium P is described as paper, but the present invention is not limited to this configuration. The recording medium P is not limited to paper and may be made of metal, resin, or food. In the above embodiments, a configuration in which a liquid jet head is mounted on a liquid jet recording apparatus has been described, but the present invention is not limited to this configuration. Specifically, the liquid ejected from the liquid jet head is not limited to the liquid that lands on the recording medium. For example, the liquid can also be a drug solution prepared in pharmaceutical preparation, a food additive such as a seasoning or fragrance added to food, or an aromatic sprayed into the air.

[0108] In the above-described embodiment, the configuration in which the Z direction coincides with the direction of gravity has been described. However, the present invention is not limited to this configuration, and the Z direction may be aligned with the horizontal direction. In the above-mentioned embodiment, the configuration in which the ink is ejected by deforming the actuator plate in the direction of expanding the volume of the discharge channel by applying a voltage and then restoring the actuator plate (so-called pull-in) is described, but the present invention is not limited to this configuration. The head chip involved in the present disclosure may also be a configuration in which the ink is ejected by deforming the actuator plate in the direction of reducing the volume of the discharge channel by applying a voltage (so-called press-in). In the case of press-in, the actuator plate is deformed in a manner of bulging toward the discharge channel by applying a driving voltage. As a result, the volume in the discharge channel is reduced, and the pressure in the discharge channel is increased, and the ink in the discharge channel is discharged to the outside through the nozzle hole. If the driving voltage is reduced to zero, the actuator plate is restored. As a result, the volume in the discharge channel is restored to its original state.

[0109] In the above embodiment, the chip modules 51A and 51B are stacked on each other, but the present invention is not limited to this configuration. The head chip 50 may be composed of only the first chip module 51A. In the above embodiment, the side-shooting type is used as an example of a head chip, but the invention is not limited to this configuration. For example, the present disclosure can also be applied to a so-called side-shooting type head chip 50 that ejects ink from the center of the extension direction of the ejection channel 71. In addition, the head chip can also be a so-called top-shooting type, in which the direction of pressure applied to the ink and the direction of ink ejection are the same. In the case of the top-shooting type, the following portion functions as a driving portion: the portion facing the pressure chamber that contains the ink and deforms to expand or contract the pressure chamber.

[0110] In the above embodiment, the second wiring portion 96 overlaps the second region 95b when viewed in the thickness direction (X direction), but the present invention is not limited to this configuration. It suffices that the second region 95b and the second wiring portion 96 are at least electrically connected. In this case, for example, a configuration may be employed in which the back-side edge of the second region 95b and the front-side edge of the second wiring portion 96 do not overlap when viewed in the X direction, but are connected only in the Y direction.

[0111] In the above embodiment, the second wiring portion 96 is formed in the region including a portion of the second region 95b of the first wiring portion 95, but the present invention is not limited to this configuration. The second wiring portion 96 may overlap the entire first wiring portion 95 in the Z direction. In the above embodiment, the portion of the routing wiring 93 where the dividing groove 79 is formed is used as the second region 95b, and the second wiring portion 96 is additionally formed in the second region 95b. However, the present invention is not limited to this configuration. For example, the second wiring portion may be additionally formed in a portion (second region) of the driving wiring that connects the common electrode 87 or the individual electrode 91 to the external wiring, such as the common terminal 88 or the individual terminal 92, where the resistance is likely to increase. In the above embodiment, the configuration including the first wiring forming step S13 and the second wiring forming step S17 has been described. However, the second wiring forming step S17 may be performed on an actuator plate on which the first wiring portion 95 has already been formed.

[0112] Furthermore, components in the above-described embodiments may be appropriately replaced with well-known components without departing from the spirit of the present disclosure, and the above-described modifications may be appropriately combined. Description of Reference Numerals

[0113] 1: Printer (liquid jet recording device) 5: Inkjet head (liquid ejection head) 50: Head chip 61: First actuator plate (chip body, actuator plate) 71: discharge channel (pressure chamber, injection channel) 72: Non-discharge channel (non-injection channel) 75: Driving wall (driving part) 79: Split slot 87: Common electrode (driving electrode) 88: Common terminal 91: Single electrode (driving electrode) 92: Single terminal 93: Route wiring (drive wiring) 95: 1st wiring section 95a: Area 1 95b: Area 2 96: Second wiring section 101: Second actuator plate (chip body, actuator plate).

Claims

1. A head chip comprising: a chip body having a pressure chamber for accommodating liquid and a driving portion disposed at a portion facing the pressure chamber; a driving electrode formed on the driving portion; and a driving wiring formed in the chip body and connecting the driving electrode and external wiring; The drive wiring comprises: a first wiring portion including a first region and a second region, the second region being connected to the first region in a direction in which the drive wiring extends and having a smaller cross-sectional area perpendicular to the extending direction than the first region; and The second wiring portion is connected to at least the second region in a direction intersecting the extending direction.

2. The head chip according to claim 1, wherein: The second wiring portion is provided only in a portion of the drive wiring including the second region.

3. The head chip according to claim 1 or claim 2, wherein: The second wiring portion is provided so as to cover at least the second region in a first direction perpendicular to a film formation surface of the drive wiring in the chip body when viewed from the extending direction.

4. The head chip according to claim 1 or claim 2, wherein: The second wiring portion is provided so as to be integrally connected to at least the second region in a second direction along the film formation surface of the drive wiring in the chip body when viewed from the extending direction.

5. The head chip according to claim 4, wherein: The chip main body includes an actuator plate formed by laminating two piezoelectric substrates having different polarization directions in the second direction along the second direction. The actuator plate is formed with: an injection channel as said pressure chamber containing a liquid; as well as a non-injection channel adjacent to the injection channel and not containing liquid, The driving portion is composed of a portion of the actuator plate located between the ejection channel and the non-ejection channel. The driving electrode comprises: a common electrode formed over the entire area in the second direction at a portion of the driving portion facing the ejection channel; as well as A separate electrode is formed over the entire area in the second direction in a portion of the driving portion facing the non-ejection channel. The driving wiring is connected to the individual electrode at a portion of the driving portion facing the non-ejection channel.

6. The head chip according to claim 5, wherein: A dividing groove is formed on the surface of the actuator plate, the dividing groove separating a common terminal connecting the common electrode and the external wiring from an individual terminal connecting the individual electrode and the external wiring. The second region is a portion of the driving portion that faces the non-ejection channel and is located at a portion that overlaps with the dividing groove in the extending direction. 7 . A liquid ejecting head comprising the head chip according to claim 1 . 8 . A liquid jet recording apparatus comprising the liquid jet head according to claim 7 .

9. A method for manufacturing a head chip, comprising: forming a drive wiring line on a chip body, wherein the drive wiring line is connected to an external wiring line; the chip body having a pressure chamber for accommodating a liquid and a drive portion disposed facing the pressure chamber and having the drive electrode formed thereon; The drive wiring forming process forms a second wiring portion in the chip body having a first wiring portion having a first region and a second region, in a manner connected at least relative to the second region in a direction intersecting the extension direction, wherein the second region is connected relative to the first region in the extension direction of the drive wiring, and a cross-sectional area perpendicular to the extension direction is smaller than that of the first region.

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