Liquid ejection head

Abstract

To provide a liquid discharge head capable of decreasing a resistance value of an electrode.SOLUTION: A liquid discharge head comprises an actuator, a substrate, and an electrode. The actuator includes a plurality of pressure chambers arranged in one direction. The substrate is provided with the actuator. The electrode is formed on the substrate and the actuator. In the electrode, a conductor portion formed on the substrate is formed of a multilayer film which comprises a Ni sputter film, an electroless Ni plating film, a first electrolytic metal plating film, and a second electrolytic metal plating film of a metal kind different from that of the first electrolytic metal plating film. In the electrode, the conductor portion formed on the actuator is formed of the Ni sputter film and the electroless Ni plating film. The electrode drives the pressure chambers.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a liquid ejection head. [Background technology]

[0002] Conventionally, liquid ejection heads such as inkjet heads have been known that have a ceramic substrate on which a plurality of partition walls are formed at predetermined intervals, with piezoelectric ceramics provided to allow ink to pass between the partition walls. In the liquid ejection head, drive electrodes are formed on the side surfaces of each partition wall, and the end faces of the partition walls have inclined surfaces that extend outward from the top to the bottom. The electrodes of the liquid ejection head are formed as patterns of lead lines on the inclined surfaces of the partition walls and on the substrate.

[0003] For example, in order to increase the speed of ink ejection, a liquid ejection head uses an independent drive structure with grooves for ejecting liquid and grooves that do not eject liquid.In one example of a liquid ejection head with an independent drive structure, the electrodes of the grooves for ejecting liquid are bundled together in the center of the substrate to form a common GND electrode, and the electrodes of the grooves that do not eject liquid are pulled out to the driver IC side.

[0004] For example, when ink is ejected by simultaneously driving all nozzles, if the resistance of the common GND electrode is high, differences in the drive waveform will be observed between the ends and the center of the groove array, which may result in deterioration of print quality such as dot diameter and linearity. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-37057 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is to provide a liquid ejection head capable of reducing the resistance value of the electrodes. [Means for solving the problem]

[0007] The liquid ejection head of the embodiment includes an actuator, a substrate, and an electrode. The actuator has a plurality of pressure chambers arranged in one direction. The substrate is provided with the actuator. The electrode is formed on the substrate and the actuator. The conductive portion of the electrode formed on the substrate is formed of a multilayer film including a Ni sputtered film, an electroless Ni plated film, a first electrolytic metal plated film, and a second electrolytic metal plated film of a different metal from the first electrolytic metal plated film. The conductive portion of the electrode formed on the actuator is formed of the Ni sputtered film and the electroless Ni plated film. The electrode drives the pressure chamber. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a configuration of a liquid ejection head according to an embodiment. [Figure 2] FIG. 2 is a bottom view showing the configuration of the liquid ejection head according to the embodiment. [Figure 3] FIG. 2 is a bottom view illustrating the configuration of the liquid ejection head according to the embodiment, with some parts omitted. [Figure 4] FIG. 2 is a perspective view showing the configuration of a head main body of the liquid ejection head according to the embodiment. [Figure 5] FIG. 2 is a cross-sectional view showing the configuration of a head main body according to the embodiment. [Figure 6] FIG. 2 is a plan view showing the configuration of a head main body according to the embodiment. [Figure 7] FIG. 2 is a cross-sectional view showing the configuration of a head main body according to the embodiment, with some parts omitted. [Figure 8] FIG. 2 is a cross-sectional view showing the configuration of a substrate and electrodes of a head main body according to the embodiment. [Figure 9] FIG. 2 is a cross-sectional view showing the configuration of an actuator and electrodes of the head main body according to the embodiment. [Figure 10] 4 is a flowchart showing an example of a method for manufacturing a liquid ejection head according to an embodiment. [Figure 11] FIG. 1 is an explanatory diagram showing the configuration of a liquid ejection device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A liquid ejection head 1 according to an embodiment and a liquid ejection device 2 using the liquid ejection head 1 will be described below with reference to FIGS. 1 to 11. FIG. 1 is a perspective view showing the configuration of a liquid ejection head 1 according to a first embodiment, and FIG. 2 is a bottom view showing the configuration of the liquid ejection head 1. FIG. 3 is a bottom view showing the configuration of the liquid ejection head 1 with the nozzle plate 114 omitted. FIG. 4 is a perspective view showing the configuration of a head main body 11 of the liquid ejection head 1 with a portion of the nozzle plate 114 cut away, and FIG. 5 is a cross-sectional view showing the configuration of the head main body 11. FIG. 6 is a plan view showing the configuration of a substrate 111, actuators 113, and electrodes 117 of the head main body 11. FIG. 7 is a cross-sectional view showing the configuration of a substrate 111, actuators 113, and electrodes 117 of the head main body 11. FIG. 8 is a cross-sectional view showing the configuration of the substrate 111 and electrodes 117 of the head main body 11, and FIG. 9 is a cross-sectional view showing the configuration of the actuators 113 and electrodes 117 of the head main body 11. Fig. 10 is a flow chart showing an example of forming the electrodes 117 of the head main body 11, as an example of a method for manufacturing the liquid ejection head 1. Fig. 11 is an explanatory diagram showing the configuration of a liquid ejection device 2 using the liquid ejection head 1. Note that in each figure, the configuration is enlarged, reduced, or omitted as appropriate for ease of explanation.

[0010] The liquid ejection head 1 is a share mode inkjet head provided in a liquid ejection device 2 such as the inkjet recording device shown in Fig. 11. The liquid ejection head 1 is provided in a head unit 2130 provided in the liquid ejection device 2 and including a supply tank 2132 as a liquid storage section.

[0011] The liquid ejection head 1 is supplied with ink as a liquid stored in a supply tank 2132. The liquid ejection head 1 may be a non-circulation type head that does not circulate ink, or a circulation type head that circulates ink. In this embodiment, the liquid ejection head 1 will be described using an example of a non-circulation type head. The liquid ejection head 1 is also connected to a temperature adjustment device 2116 provided in the liquid ejection device 2, and is supplied with temperature adjustment liquid (temperature adjustment water) that controls the temperature of the ink.

[0012] 1 to 4, the liquid ejection head 1 includes a head main body 11, a manifold unit 12, a circuit board 13, and a cover 14. For example, the liquid ejection head 1 is a side-shooter type four-row integrated structure head that includes two sets of head main bodies 11, each having a pair of actuators 113.

[0013] 3 to 7, the head body 11 includes a substrate 111, a frame member 112, an actuator 113 having a plurality of pressure chambers 1131 and a plurality of air chambers 1132, and a nozzle plate 114. The head body 11 has a common liquid chamber 116 that communicates with the plurality of pressure chambers 1131 of the actuator 113.

[0014] The head body 11 also includes electrodes 117 on the substrate 111 and the actuator 113 for driving a plurality of pressure chambers 1131 of the actuator 113 .

[0015] In this embodiment, an example will be described in which the head main body 11 has two actuators 113, and the common liquid chamber 116 has one first common liquid chamber 1161 and two second common liquid chambers 1162. The common liquid chamber 116 has, for example, the first common liquid chamber 1161 that communicates with one opening of the multiple pressure chambers 1131 of the actuator 113, the second common liquid chamber 1162 that communicates with the other opening of the multiple pressure chambers 1131 of the actuator 113, and a third common liquid chamber 1163 that connects both ends of the first common liquid chamber 1161 to both ends of the two second common liquid chambers 1162.

[0016] The substrate 111 is formed, for example, in the shape of a rectangular plate and made of a ceramic material. The substrate 111 is formed, for example, in the shape of a rectangle that is long in one direction. A wiring pattern that becomes part of the electrode 117 is formed on one surface of the substrate 111. As a specific example, a wiring pattern that becomes part of a plurality of individual electrodes 118 (described later) of the electrode 117 and a wiring pattern that becomes part of a single common electrode 119 are formed on one surface of the substrate 111. A pair of actuators 113 are provided on one surface of the substrate 111, lined up in the short direction of the substrate 111. The one surface of the substrate 111 refers to one surface of the substrate 111. The substrate 111 has, for example, a single supply port 1111 and a plurality of discharge ports 1112. The supply port 1111 and the discharge port 1112 are through holes that penetrate between both main surfaces of the substrate 111.

[0017] The supply port 1111 is an inlet for supplying ink to the first common liquid chamber 1161. The supply port 1111 is a through hole formed in the center of the substrate 111 in the short direction. The supply port 1111 extends along the longitudinal direction of the substrate 111. In other words, the supply port 1111 is, for example, an elongated hole that is long in one direction along the longitudinal direction of the actuators 113 and the longitudinal direction of the first common liquid chamber 1161. The supply port 1111 is provided between the pair of actuators 113, and opens at a position facing the first common liquid chamber 1161.

[0018] The discharge port 1112 is an outlet for discharging ink from the second common liquid chamber 1162. A plurality of discharge ports 1112, for example, four discharge ports 1112, are provided. Each discharge port 1112 is provided, for example, in each of the two third common liquid chambers 1163. Note that a plurality of discharge ports 1112 may be provided in the second common liquid chamber 1162.

[0019] The frame member 112 is fixed to one main surface of the substrate 111 with an adhesive or the like. The frame member 112 surrounds a supply port 1111, a plurality of discharge ports 1112, and an actuator 113, which are provided in the substrate 111. For example, the frame member 112 has a stepped structure.

[0020] For example, the frame member 112 is formed in a rectangular frame shape, thereby forming an opening that is long in one direction along the longitudinal direction of the frame member 112. In the opening of the frame member 112, a pair of actuators 113, a supply port 1111, and four discharge ports 1112 are arranged.

[0021] The pair of actuators 113 is adhered to the mounting surface of the substrate 111. The pair of actuators 113 is arranged in two rows on the substrate 111 with a supply port 1111 between them. The actuators 113 are formed in the shape of a plate that is long in one direction. The actuators 113 are placed inside the opening of the frame member 112 and adhered to the main surface of the substrate 111.

[0022] 3 and 6, the actuator 113 has a plurality of pressure chambers 1131 arranged at equal intervals in the longitudinal direction, and air chambers 1132 arranged at equal intervals in the longitudinal direction and between adjacent pressure chambers 1131. In other words, the actuator 113 has a plurality of pressure chambers 1131 and air chambers 1132 arranged alternately along the longitudinal direction.

[0023] The surface of the actuator 113 opposite to the substrate 111 is bonded to the nozzle plate 114. The actuators 113 are arranged in a row at equal intervals in the longitudinal direction, and a plurality of grooves are formed along a direction perpendicular to the longitudinal direction. The plurality of grooves form a plurality of pressure chambers 1131 and a plurality of air chambers 1132. In other words, the actuator 113 has a plurality of piezoelectric bodies 1133 that are arranged in a row at equal intervals in the longitudinal direction and are driving elements that constitute walls that form the grooves between them. The plurality of piezoelectric bodies 1133 form a plurality of pressure chambers 1131 and a plurality of air chambers 1132 between adjacent piezoelectric bodies 1133, and the volume of the pressure chambers 1131 is changed by applying a driving voltage.

[0024] For example, the width of the actuator 113 in the short side direction gradually increases from the top side toward the substrate 111 side. The cross section of the actuator 113 along the direction perpendicular to the longitudinal direction (short side direction) is formed into a trapezoidal shape. That is, the actuator 113 has an inclined surface 1134 that is inclined on the side surface portion in the short side direction. The side surface portion (inclined surface 1134) is disposed opposite the first common liquid chamber 1161 and the second common liquid chamber 1162.

[0025] As a specific example, the actuator 113 is formed of a laminated piezoelectric member in which two rectangular piezoelectric material plates elongated in one direction are bonded together facing each other so that their polarization directions are opposite to each other. Here, the piezoelectric material is, for example, PZT (lead zirconate titanate). The actuator 113 is bonded to the mounting surface of the substrate 111 with, for example, a thermosetting epoxy adhesive. The actuator 113 then forms an inclined surface 1134 by, for example, cutting. In addition, the surfaces of the substrate 111 and the actuator 113 on which the multiple individual electrodes 118 and the common electrode 119 of the electrode 117 are patterned are polished, for example, by polishing to form a polished surface. For example, the polished surface is formed on the inclined surface 1134 of the actuator 113 and on the substrate 111 at the base of the inclined surface 1134. Furthermore, the actuator 113 is formed, for example, by cutting, with a plurality of grooves that form a plurality of pressure chambers 1131 and a plurality of air chambers 1132, and with piezoelectric bodies (drive elements) 1133 that are side walls that separate adjacent grooves.

[0026] Furthermore, the actuator 113 is formed with a wiring pattern that will become part of the plurality of individual electrodes 118 and a wiring pattern that will become part of one or more common electrodes 119 .

[0027] The pressure chamber 1131 deforms when the liquid ejection head 1 performs an operation such as printing, thereby ejecting ink from the nozzle 1141. The pressure chamber 1131 has an inlet that opens to a first common liquid chamber 1161 and an outlet that opens to a second common liquid chamber 1162. Ink flows into the pressure chamber 1131 from the inlet and flows out from the outlet. Note that the pressure chamber 1131 may be configured so that ink flows in from both the openings described as the inlet and outlet.

[0028] As shown by the dashed lines in FIG. 7 , the air chamber 1132 is separated from the first common liquid chamber 1161 and the second common liquid chamber 1162 by having its inlet and outlet sides blocked by liquid-proof walls 1135 made of a photosensitive resin or the like. Specifically, the liquid-proof walls 1135 of the air chamber 1132 are formed by injecting ultraviolet-curable resin into the groove that forms the air chamber 1132, and then irradiating necessary portions, such as both ends of the groove (the inlet and outlet sides), with ultraviolet light using a mask plate or the like. Such liquid-proof walls 1135 prevent ink from entering the air chamber 1132. Furthermore, the air chamber 1132 is blocked by the nozzle plate 114, and no nozzles 1141 are provided. Therefore, ink does not flow into the air chamber 1132.

[0029] The nozzle plate 114 is formed in a plate shape. The nozzle plate 114 is fixed with an adhesive or the like to the main surface of the frame member 112 opposite the substrate 111. The nozzle plate 114 has a plurality of nozzles 1141 formed at positions facing the plurality of pressure chambers 1131. In this embodiment, the nozzle plate 114 has two nozzle rows 1142 in which the plurality of nozzles 1141 are aligned in one direction.

[0030] The first common liquid chamber 1161 is formed between the central sides of the pair of actuators 113, excluding both end portions, and constitutes an ink flow path from the supply port 1111 to one opening of the multiple pressure chambers 1131 of each actuator 113. The first common liquid chamber 1161 extends along the longitudinal direction of the actuators 113.

[0031] The second common liquid chambers 1162 are formed between each actuator 113 and the frame member 112. The second common liquid chambers 1162 form ink flow paths from the third common liquid chamber 1163 to the other openings of the multiple pressure chambers 1131. The second common liquid chambers 1162 extend along the longitudinal direction of the actuators 113.

[0032] The third common liquid chamber 1163 is adjacent to, for example, both ends in the longitudinal direction of the actuator 113. The third common liquid chamber 1163 communicates with the first common liquid chamber 1161 and the two second common liquid chambers 1162 at both ends in the longitudinal direction of the pair of actuators 113. The third common liquid chamber 1163 forms a flow path for part of the ink that reaches the second common liquid chamber 1162 from the first common liquid chamber 1161 without passing through the multiple pressure chambers 1131 of each actuator 113. The third common liquid chamber 1163 also forms a flow path for ink from the first common liquid chamber 1161 and the two second common liquid chambers 1162 to the discharge port 1112.

[0033] The electrode 117 is an electrode film and includes, for example, a plurality of individual electrodes 118 that respectively drive the plurality of pressure chambers 1131, and one or more common electrodes 119 that simultaneously drive the plurality of pressure chambers 1131.

[0034] As shown in Figures 7 to 9, the electrode 117 has a first electrode portion 1171 which is a conductive portion formed on the upper surface of the substrate 111 and the inclined surface 1134 of the actuator 113, and a second electrode portion 1172 which is a conductive portion formed on the bottom and side surfaces of the multiple pressure chambers 1131 and multiple air chambers 1132 of the actuator 113.

[0035] The first electrode portion 1171 is a wiring pattern (lead line). The first electrode portion 1171 is formed of a multilayer film. As shown in Fig. 8, the first electrode portion 1171 includes a Ni sputtered film 11731, an electroless Ni plated film 11732, a first electrolytic metal plated film 11733, and a second electrolytic metal plated film 11734 made of a different metal from the first electrolytic metal plated film 11733.

[0036] The first electrolytic metal plating film 11733 is, for example, an electrolytic Ni plating film. Hereinafter, the first electrolytic metal plating film 11733 will be described as the electrolytic Ni plating film 11733. The second electrolytic metal plating film 11734 is, for example, an electrolytic Au plating film. Hereinafter, the second electrolytic metal plating film 11734 will be described as the electrolytic Au plating film 11734.

[0037] The second electrode portion 1172 is formed of a multilayer film having fewer layers than the first electrode portion 1171. As shown in Fig. 9, the second electrode portion 1172 is formed of a multilayer film in which a conductor portion formed in a groove between adjacent piezoelectric bodies 1133 of the actuator 113 is formed of a Ni sputtered film 11731 and an electroless Ni plated film 11732. The second electrode portion 1172 is provided continuously with the corresponding first electrode portion 1171.

[0038] That is, the first electrode portion 1171 is provided with an electrolytic Ni plating film (first electrolytic metal plating film) 11733 and an electrolytic Au plating film (second electrolytic metal plating film) 11734, and therefore has a thicker film thickness and a lower resistance value than the second electrode portion 1172.

[0039] Next, as an example of a method for manufacturing the liquid ejection head 1, an example of forming the electrode 117 will be described with reference to the flow chart shown in FIG.

[0040] First, sputtering is performed on predetermined regions of the substrate 111 and the actuator 113 to form a Ni sputtered film 11731 (ACT1). As a specific example, the Ni sputtered film 11731 is formed on the substrate 111 including the polished surface, on the inclined surface 1134 of the actuator 113, and on the inner surfaces of the plurality of piezoelectric bodies 1133 that constitute the plurality of pressure chambers 1131 and the plurality of air chambers 1132 of the actuator 113. At this time, the Ni sputtered film 11731 is formed in a region including the range where the plurality of individual electrodes 118 and the common electrode 119 are to be provided.

[0041] Next, electroless plating is used to form an electroless Ni plating film 11732 on the Ni sputtered film 11731 (ACT2). For example, the electroless Ni plating film 11732 is formed using the Ni sputtered film 11731 as a catalyst.

[0042] Next, an electrolytic plating method is used to form an electrolytic Ni plating film 11733 on the electroless Ni plating film 11732 (ACT3). At this time, because the width of the grooves formed between the multiple piezoelectric bodies 1133 is small, the electrolytic Ni plating film 11733 is formed only on the electroless Ni plating film 11732 formed on the substrate 111 and the inclined surface 1134 of the actuator 113. In other words, by using the electrolytic plating method, the electrolytic Ni plating film 11733 is formed only on the electroless Ni plating film 11732 in the region where the first electrode portion 1171 is to be provided.

[0043] Next, the electrodes formed by the Ni sputtered film 11731, the electroless Ni plated film 11732, and the electrolytic Ni plated film 11733 are patterned by photolithography or the like (ACT4). The electrode pattern at this time is, for example, the pattern of the plurality of individual electrodes 118 and the common electrode 119 formed on the substrate 111 and the actuator 113.

[0044] Next, an electrolytic Au plating film 11734 is formed on the patterned electrolytic Ni plating film 11733 using an electrolytic plating method (ACT5). At this time, because the width of the grooves formed between the plurality of piezoelectric bodies 1133 is small, the electrolytic Au plating film 11734 is formed on the substrate 111 and the inclined surface 1134 of the actuator 113, and is formed only on the patterned electroless Ni plating film 11732. By these example steps, an electrode 117 is formed in the wiring pattern of the plurality of individual electrodes 118 and the common electrode 119, including first electrode portions 1171 and second electrode portions 1172 which have different thicknesses and different layer configurations.

[0045] The plurality of individual electrodes 118 apply a driving voltage individually to the plurality of piezoelectric bodies 1133, which are piezoelectric bodies. The plurality of individual electrodes 118 individually deform each pressure chamber 1131. The individual electrodes 118 are formed by a wiring pattern formed on the substrate 111 and a wiring pattern formed on the actuator 113. The individual electrodes 118 are a wiring pattern formed by a first electrode portion 1171 and a second electrode portion 1172. The plurality of individual electrodes 118 are connected to the circuit board 13.

[0046] 7, a plurality of individual electrodes 118 are formed on the inner surfaces of each pressure chamber 1131, the inclined surface 1134 of the actuator 113, and the substrate 111. Specifically, the individual electrodes 118 are formed by the second electrode portion 1172 on the side surfaces of the piezoelectric body 1133 that forms the pressure chamber 1131 and on the bottom surface of the pressure chamber 1131. The individual electrodes 118 are also formed by the first electrode portion 1171 on the inclined surface 1134 and the polished surface of the substrate 111. The individual electrodes 118 extend from within the pressure chamber 1131 to the ends of the substrate 111 in the lateral direction, and have their ends located at the connection portions 1116 to which the circuit board 13 of the substrate 111 is connected. The individual electrodes 118 are provided so as to be in close contact with the bottom of the pressure chamber 1131 and the surface of the piezoelectric member that forms the piezoelectric body 1133. The individual electrodes 118 are formed, for example, from a nickel thin film. For example, the individual electrodes 118 on the substrate 111 are covered on the lower surface side of the frame member 112 with an adhesive that bonds the frame member 112 to the substrate 111 .

[0047] The common electrode 119 applies the same driving voltage to all of the multiple piezoelectric bodies 1133. The common electrode 119 simultaneously deforms the multiple pressure chambers 1131. The common electrode 119 is formed by a wiring pattern formed on the substrate 111 and a wiring pattern formed on the actuator 113. The common electrode 119 is a wiring pattern provided from the inner circumferential surface of the supply port 1111 of the substrate 111 to the piezoelectric bodies 1133 that form the multiple air chambers 1132. The common electrode 119 is connected to the circuit board 13.

[0048] 7, the common electrode 119 is formed on the substrate 111, avoiding the inner surfaces of the air chambers 1132, the inclined surfaces 1134 of the actuators 113, and the areas where the individual electrodes 118 are formed. Specifically, the common electrode 119 is formed on the side surfaces of the piezoelectric bodies 1133 that form the air chambers 1132 and on the bottom surfaces of the air chambers 1132 by the second electrode portions 1172. The common electrode 119 is also formed on the inclined surfaces 1134 from within the air chambers 1132 toward the center of the substrate 111 by the first electrode portions 1171, on the polished surface of the substrate 111 between the pair of actuators 113, and on the inner circumferential surface of the supply port 1111. The common electrode 119 extends to the ends of the substrate 111 in the lateral direction, and an end of the common electrode 119 is disposed at a connection portion 1116 to which the circuit board 13 of the substrate 111 is connected.

[0049] In other words, the common electrode 119 is integrally formed on the inclined surface 1134 of the actuator 113 and the inner surface of the multiple air chambers 1132, from the connection portion 1116 formed at the short-side end of the substrate 111 through the center side of the short-side of the substrate 111 between the pair of actuators 113.

[0050] 1, 2, 4, and 5, the manifold unit 12 includes a manifold 121, a top plate 122, an ink supply pipe 123, an ink discharge pipe 124, and a pair of temperature control pipes, a temperature-controlled water supply pipe 125 and a temperature-controlled water discharge pipe. The numbers of the ink supply pipes 123, the ink discharge pipes 124, the temperature-controlled water supply pipes 125, and the temperature-controlled water discharge pipes can be set as appropriate.

[0051] 5, the manifold 121 includes a supply flow path 1211 that is continuous with the supply port 1111 of the substrate 111 and forms a liquid supply flow path, a discharge flow path that is continuous with the discharge port 1112 of the substrate 111 and forms a liquid discharge flow path, and a temperature control flow path 1213 that forms a flow path for a temperature control fluid.

[0052] One main surface of the manifold 121 is fixed to the main surface of the substrate 111. A top plate 122 is fixed to the main surface of the manifold 121 opposite to the main surface to which the substrate 111 is fixed. In addition, for example, an ink supply pipe 123, an ink discharge pipe 124, a temperature-controlled water supply pipe 125, and a temperature-controlled water discharge pipe are fixed to the manifold 121 via the top plate 122.

[0053] The supply flow channel 1211 is a flow channel formed by holes or grooves in the manifold 121. The supply flow channel 1211 fluidly connects the ink supply tube 123 and the supply port 1111 of the substrate 111.

[0054] The discharge channels are channels formed by holes or grooves in the manifold 121. The discharge channels fluidly connect the ink discharge tubes 124 and the discharge ports 1112 in the substrate 111.

[0055] The temperature adjustment flow path 1213 is a flow path formed by holes or grooves in the manifold 121. The temperature adjustment flow path 1213 fluidly connects the temperature adjustment water supply pipe 125 and the temperature adjustment water discharge pipe.

[0056] Both ends of the temperature adjustment flow path 1213 are openings connected to a temperature adjustment water supply pipe 125 and a temperature adjustment water discharge pipe provided on one main surface of the manifold 121. In addition, the temperature adjustment flow path 1213 is formed so as to be able to exchange heat with the substrate 111 fixed to the manifold 121.

[0057] The top plate 122 is provided on the surface of the manifold 121 opposite to the surface on which the substrate 111 is provided. The top plate 122 covers the manifold 121, thereby sealing the supply flow path 1211, the discharge flow path, and the temperature adjustment flow path 1213.

[0058] The top plate 122 also has openings that connect the pipes 123, 124, and 125 and allow the pipes 123, 124, and 125 and the flow channels 1211 and 1213 to communicate with each other.

[0059] The ink supply pipe 123 is connected to the supply flow path 1211. The ink discharge pipe 124 is connected to the discharge flow path. The temperature control water supply pipe 125 and the temperature control water discharge pipe are connected to the primary side and secondary side of the temperature control flow path 1213.

[0060] As shown in Figure 4, the circuit board 13 comprises a wiring film 131 having one end connected to the connection portion 1116 of the substrate 111, a driver IC 132 mounted on the wiring film 131, and a printed wiring board 133 mounted on the other end of the wiring film 131.

[0061] The circuit board 13 drives the actuator 113 by applying a drive voltage to the wiring pattern of the actuator 113 via the driver IC 132 , thereby increasing or decreasing the volume of the pressure chamber 1131 and causing droplets to be ejected from the nozzle 1141 .

[0062] The wiring film 131 is connected to the plurality of individual electrodes 118 and the common electrode 119. For example, the wiring film 131 is an ACF (anisotropic conductive film) fixed to the connection portion of the substrate 111 by thermocompression bonding or the like. For example, a plurality of wiring films 131 to be connected are provided for one head main body 11. In this embodiment, two wiring films 131 are connected to one actuator 113. The wiring film 131 is, for example, a COF (chip on film) on which a driver IC 132 is mounted.

[0063] The driver IC 132 is connected to the plurality of individual electrodes 118 and the common electrode 119 via the wiring film 131. The driver IC 132 may be connected to the plurality of individual electrodes 118 and the common electrode 119 by other means such as ACP (anisotropic conductive paste), NCF (non-conductive film), and NCP (non-conductive paste) instead of the wiring film 131.

[0064] The printed wiring board 133 is a PWA (Printing Wiring Assembly) on which various electronic components and connectors are mounted.

[0065] The cover 14 includes, for example, an outer shell 141 that covers the side surfaces of the pair of head bodies 11, the manifold unit 12, and the circuit board 13, and a mask plate 142 that covers a portion of the pair of head bodies 11 on the nozzle plate 114 side.

[0066] The outer shell 141 exposes, for example, the ink supply pipe 123, the ink discharge pipe 124, the temperature-controlled water supply pipe 125, and the temperature-controlled water discharge pipe of the manifold unit 12, and the end of the circuit board 13 to the outside.

[0067] The mask plate 142 covers the pair of head bodies 11 except for the plurality of nozzles 1141 and the areas of the nozzle plate 114 around the plurality of nozzles 1141 .

[0068] The liquid ejection head 1 configured in this manner has, in the head body 11, a plurality of individual electrodes 118 that can apply a drive voltage to each piezoelectric element 1133 individually, and a common electrode 119 that can apply a drive voltage to all piezoelectric elements 1133.

[0069] Therefore, the liquid ejection head 1 can selectively drive the multiple pressure chambers 1131 individually or in common. When the pressure chamber 1131 is driven, the pressure chamber 1131 undergoes a shear mode deformation, and the ink supplied to the pressure chamber 1131 is pressurized. Therefore, the liquid ejection head 1 can selectively eject pressurized ink from the nozzle 1141 facing the deformed pressure chamber 1131.

[0070] Furthermore, the conductive portions of electrode 117 on substrate 111 and on inclined surface 1134 of actuator 113 are formed of first electrode portion 1171, which is a multilayer film formed of Ni sputtered film 11731 / electroless Ni plated film 11732 / electrolytic Ni plated film (first electrolytic metal plated film) 11733 / electrolytic Au plated film (second electrolytic metal plated film) 11734. Furthermore, the conductive portions of electrode 117, which are formed on the surfaces of grooves between piezoelectric bodies 1133 of actuator 113, are formed of second electrode portion 1172, which is a multilayer film formed of Ni sputtered film 11731 / electroless Ni plated film 11732. Therefore, electrode 117 can reduce the resistance value of first electrode portion 1171, which is a wiring pattern up to piezoelectric body 1133, which is the driving element. In particular, by forming the first electrode portion 1171 on the common electrode 119, when driving multiple pressure chambers 1131, it is possible to suppress differences in ejection performance between the central side and the end side in the arrangement direction of the nozzles 1141 of the head main body 11.

[0071] Furthermore, the conductivity of first electrode portion 1171 is reduced by electrolytic Ni plating film 11733 formed by electrolytic plating. Therefore, by providing first electrode portion 1171 with electrolytic Ni plating film 11733, the electrical resistance can be reduced.

[0072] Furthermore, by providing the electrolytic Ni plating film 11733, the thickness of the electrolytic Au plating film 11734 can be reduced. That is, there is a limit to how thick the electrolytic Au plating film 11734 can be formed, because the high malleability of Au can cause burrs and other problems in the finished product after machining. Furthermore, from the standpoint of production efficiency, it is difficult to reduce the resistance of the Ni sputtered film 11731 and the electroless Ni plating film 11732 by thickening them. However, by providing the electrolytic Ni plating film 11733, which has lower electrical resistance than the electroless Ni plating film 11732, the first electrode portion 1171 of the embodiment can reduce electrical resistance even if the electrolytic Au plating film 11734 is thin, and can be formed with high production efficiency.

[0073] An inkjet recording apparatus 2 having a liquid ejection head 1 will be described below with reference to Fig. 11. The inkjet recording apparatus 2 includes a housing 2111, a medium supply unit 2112, an image forming unit 2113, a medium ejection unit 2114, a transport device 2115 which is a support device, a temperature adjustment device 2116, a maintenance device 2117, and a control unit 2118. The inkjet recording apparatus 2 also includes a temperature adjustment device which adjusts the temperature of the ink supplied to the liquid ejection head 1.

[0074] The inkjet recording device 2 is an inkjet printer that performs an image formation process on paper P by ejecting a liquid such as ink while transporting the paper P as a recording medium, which is the object of ejection, along a predetermined transport path 2001 that runs from a medium supply section 2112 through an image forming section 2113 to a medium ejection section 2114.

[0075] The medium supply unit 2112 includes a plurality of paper feed cassettes 21121. The image forming unit 2113 includes a support unit 2120 that supports paper, and a plurality of head units 2130 that are arranged above and facing the support unit 2120. The medium discharge unit 2114 includes a paper discharge tray 21141.

[0076] The support section 2120 includes a conveyor belt 21201 that is looped in a predetermined area where image formation is performed, a support plate 21202 that supports the conveyor belt 21201 from the back side, and a plurality of belt rollers 21203 that are provided on the back side of the conveyor belt 21201.

[0077] The head unit 2130 includes liquid ejection heads 1 which are multiple inkjet heads, multiple supply tanks 2132 as liquid tanks mounted on each liquid ejection head 1, a pump 2134 which supplies ink, and a connection flow path 2135 which connects the liquid ejection heads 1 and the supply tanks 2132.

[0078] In this embodiment, the liquid ejection heads 1 are provided with four colors of liquid ejection heads 1 (cyan, magenta, yellow, and black), and four color supply tanks 2132 that respectively store ink of each color. The supply tanks 2132 are connected to the liquid ejection heads 1 by connection flow paths 2135.

[0079] The pump 2134 is a liquid-transfer pump that is configured, for example, as a piezoelectric pump. The pump 2134 is connected to the control unit 2118, and is controlled by the control unit 2118.

[0080] The connection flow path 2135 includes a supply flow path that is connected to the ink supply pipe 123 of the liquid ejection head 1. The connection flow path 2135 also includes a recovery flow path that is connected to the ink discharge pipe 124 of the liquid ejection head 1. For example, if the liquid ejection head 1 is a non-circulation type, the recovery circuit is connected to the maintenance device 2117, and if the liquid ejection head 1 is a circulation type, the recovery flow path is connected to the supply tank 2132.

[0081] The transport device 2115 transports the paper P along a transport path 2001 that runs from a paper feed cassette 21121 in the medium supply unit 2112, through the image forming unit 2113, to a paper discharge tray 21141 in the medium discharge unit 2114. The transport device 2115 includes a plurality of guide plate pairs 21211-21218 and a plurality of transport rollers 21221-21228 that are arranged along the transport path 2001. The transport device 2115 supports the paper P so that it can move relative to the liquid ejection head 1.

[0082] The temperature adjustment device 2116 includes a temperature adjustment water tank 21161, a temperature adjustment circuit 21162 such as piping or tubes for supplying the temperature adjustment water, a pump for supplying the temperature adjustment water, and a temperature adjuster for adjusting the temperature of the temperature adjustment water. The temperature adjustment device 2116 supplies the temperature adjustment water in the temperature adjustment water tank 21161, adjusted to a predetermined temperature by the temperature adjuster, to the temperature adjustment water supply pipe 125 of the liquid ejection head 1 via the temperature adjustment circuit 21162 by pumping water. The temperature adjustment device 2116 also recovers water discharged from the temperature adjustment water discharge pipe through the manifold unit 12 into the temperature adjustment water tank 21161 via the temperature adjustment circuit 21162. The temperature adjuster is, for example, a heater or a cooler. The temperature adjustment device 2116 may also be configured to adjust the temperature of ink supplied to the liquid ejection head 1.

[0083] The maintenance device 2117, for example, during maintenance, sucks and recovers ink remaining on the outer surface of the nozzle plate 114. Furthermore, if the liquid ejection head 1 is of a non-circulation type, the maintenance device 2117 recovers ink inside the head main body 11 during maintenance. Such a maintenance device 2117 has a tray, tank, or the like for storing the recovered ink.

[0084] The control unit 2118 includes a CPU 21181 as an example of a processor, a ROM (Read Only Memory) for storing various programs, a RAM (Random Access Memory) for temporarily storing various variable data and image data, and other memories, and an interface unit for inputting data from the outside and outputting data to the outside.

[0085] According to the liquid ejection head 1 and liquid ejection device 2 configured in this manner, by providing the electrolytic Ni plating film 11733 on the electroless Ni plating film 11732, the resistance value of the electrode 117 can be reduced.

[0086] It should be noted that the embodiments of the present invention are not limited to the above-described configuration. For example, in the above-described example, the liquid ejection head 1 is described as having a pair of head bodies 11, but the present invention is not limited to this and may be configured as having a single head body 11. Furthermore, in the above-described example, the liquid ejection head 1 is described as being of a non-circulating type, but it may also be of a circulating type.

[0087] In the above example, the first electrode portion 1171 of the electrode 117 is provided on each of the plurality of individual electrodes 118 and the common electrode 119, but the present invention is not limited to this. For example, the liquid ejection head 1 may be configured such that the common electrode 119 is formed by the first electrode portion 1171 and the second electrode portion 1172, and the plurality of individual electrodes 118 are formed by the second electrode portion 1172.

[0088] In the above example, the first electrolytic metal plating film 11733 of the first electrode portion 1171 is an electrolytic Ni plating film, and the second electrolytic metal plating film 11734 is an electrolytic Au plating film, but the present invention is not limited to this. That is, the metal material of the first electrolytic metal plating film 11733 is not limited as long as it can be formed on the electroless Ni plating film 11732 by electrolytic plating and has lower electrical resistance than the electroless Ni plating film 11732. Similarly, the metal material of the second electrolytic metal plating film 11734 is not limited as long as it can be formed on the first electrolytic metal plating film 11733 by electrolytic plating and is a different metal from the first electrolytic metal plating film 11733.

[0089] According to at least one of the embodiments described above, the resistance value of the electrode can be reduced by providing the first electrolytic metal plating film and the second electrolytic metal plating film on the electroless Ni plating film.

[0090] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0091] 1...liquid ejection head (inkjet head), 2...liquid ejection device (inkjet recording device), 11...head body, 12...manifold unit, 13...circuit board, 14...cover, 111...substrate, 112...frame member, 113...actuator, 114...nozzle plate, 116...common liquid chamber, 117...electrode, 118...individual electrode, 119...common electrode, 121...manifold, 122...top plate, 123...ink supply pipe, 124...ink discharge pipe, 125...temperature-controlled water supply pipe, 131...wiring film, 132...driver IC, 133...printed wiring Substrate, 141... outer shell, 142... mask plate, 1111... supply port, 1112... discharge port, 1116... connection portion, 1131... pressure chamber, 1132... air chamber, 1133... piezoelectric body (driving element), 1134... inclined surface, 1135... liquid-proof wall, 1141... nozzle, 1142... nozzle row, 1161... first common liquid chamber, 1162... second common liquid chamber, 1163... third common liquid chamber, 1171... first electrode portion, 1172... second electrode portion, 1211... supply flow path, 1213... temperature control flow path, 2001... transport path, 2111... housing, 2112... medium supply portion, 2113... image forming portion, 21 14...medium discharge section, 2115...transport device, 2116...temperature control device, 2117...maintenance device, 2118...control section, 2120...support section, 2130...head unit, 2132...supply tank, 2134...pump, 2135...connection flow path, 11731...Ni sputtered film, 11732...electroless Ni plating film, 11733...electrolytic Ni plating film (first electrolytic metal plating film), 11734...electrolytic Au plating film (second electrolytic metal plating film), 21121...paper feed cassette, 21141...paper output tray, 21201...transport belt, 21202...support plate, 21 203...belt roller, 21211...guide plate pair, 21212...guide plate pair, 21213...guide plate pair, 21214...guide plate pair, 21215...guide plate pair, 21216...guide plate pair, 21217...guide plate pair, 21218...guide plate pair, 21221...conveying roller, 21222...conveying roller, 21223...conveying roller, 21224...conveying roller, 21225...conveying roller, 21226...conveying roller, 21227...conveying roller, 21228...conveying roller, P...paper.

Claims

1. an actuator having a plurality of pressure chambers arranged in one direction; a substrate on which the actuator is provided; an electrode for driving the pressure chamber, the electrode being formed on the substrate and the actuator, the conductor portion formed on the substrate being formed of a multilayer film including a Ni sputtered film, an electroless Ni plated film, a first electrolytic metal plated film, and a second electrolytic metal plated film of a metal different from the first electrolytic metal plated film, and the conductor portion formed on the actuator being formed of the Ni sputtered film and the electroless Ni plated film; A liquid ejection head comprising:

2. The liquid ejection head according to claim 1 , wherein the electrode is a common electrode that drives the plurality of pressure chambers.

3. 2. The liquid ejection head according to claim 1, wherein the electrodes include a common electrode that drives the plurality of pressure chambers, and a plurality of individual electrodes that drive each of the plurality of pressure chambers.

4. the first electrolytic metal plating film is an electrolytic Ni plating film, 4. The liquid ejection head according to claim 1, wherein the second electrolytic metal plating film is an electrolytic Au plating film.

5. the actuator has a plurality of air chambers adjacent to the pressure chambers and arranged alternately with the pressure chambers; The actuator is provided in pair, 5. The liquid ejection head according to claim 1, wherein the substrate is formed with a slot extending along the longitudinal direction of the actuators between the pair of actuators.

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