Liquid dispensing head

Abstract

To provide a liquid discharge head configured so that sizes of a substrate and an actuator can be reduced.SOLUTION: A liquid discharge head according to an embodiment comprises a substrate, an actuator, a plurality of individual electrodes and a common electrode. The actuator, provided in the substrate, is formed long in one direction. The actuator has a first inclined surface extending along a longitudinal direction, a second inclined surface extending along the longitudinal direction, which is larger in inclination angle than the first inclined surface, and a plurality of pressure chambers extending in a transverse direction. The individual electrodes are formed on the substrate and on the first inclined surface. The plurality of individual electrodes drive the plurality of pressure chambers respectively. The common electrode is formed on the substrate and on the second inclined surface, which drives the plurality of pressure chambers.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] Embodiments of the present invention relate to a liquid ejection head.

Background Art

[0002] In recent years, liquid ejection heads such as inkjet heads are required to have high productivity, and high speed and increased droplet volume are essential. On the other hand, it is desired that the head size be reduced, and the coexistence of high productivity and miniaturization has become an issue.

[0003] On a substrate made of ceramics, a plurality of partition walls are formed at predetermined intervals, and a piezoelectric ceramic having ink flow paths between the partition walls is provided as an actuator, and a head substrate having an inclined surface that extends outward from the top to the bottom of the end surface of the partition wall is known. Wiring formation on the head substrate as described above is performed by forming a wiring pattern by photolithography. Since it is difficult to form a pattern on the side wall perpendicular to the substrate plane for the wiring pattern, the end surface in the short direction where the wiring pattern of the actuator is provided is an inclined surface that extends outward from the top to the bottom.

[0004] However, the smaller the inclination, the larger the size of the actuator in the short direction. Therefore, by increasing the angle of the inclined surface, the size of the substrate and the actuator in the short direction can be reduced. However, when the angle between the plane on the base substrate and the inclined surface of the actuator portion is 45° or more, light reflected by the inclined surface during photolithography when forming the electrode pattern irradiates the electrode pattern formed on the substrate near the foot of the inclined surface, causing a problem of electrode opening.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The problem that this invention aims to solve is to provide a liquid dispensing head that can reduce the size of the substrate and actuator. [Means for solving the problem]

[0007] The liquid dispensing head of the embodiment comprises a substrate, an actuator, a plurality of individual electrodes, and a common electrode. The actuator is provided on the substrate, An actuator formed to be elongated in the longitudinal direction of the substrate, The substrate has a first inclined surface extending along its longitudinal direction, a second inclined surface extending along the longitudinal direction with a greater inclination angle than the first inclined surface, and a plurality of pressure chambers extending in the short direction. Individual electrodes are formed on the substrate and the first inclined surface. The plurality of individual electrodes each drive the plurality of pressure chambers. A common electrode is formed on the substrate and the second inclined surface and drives the plurality of pressure chambers. The first inclined surface has an inclination angle of 45° or less with respect to the surface of the substrate on which the actuator is provided. The second inclined surface has an inclination angle greater than 45° with respect to the surface of the substrate on which the actuator is provided. [Brief explanation of the drawing]

[0008] [Figure 1] A perspective view showing the configuration of a liquid dispensing head according to an embodiment. [Figure 2] A bottom view showing the configuration of the liquid dispensing head according to the embodiment. [Figure 3] A bottom view showing the configuration of the liquid discharge head according to the embodiment, with some parts omitted. [Figure 4] A perspective view showing the configuration of the head body of the liquid dispensing head according to the embodiment. [Figure 5] A cross-sectional view showing the configuration of the head body according to the embodiment. [Figure 6] A plan view showing the configuration of the head body according to the embodiment. [Figure 7] A perspective view showing the configuration of the head body according to the embodiment, with some parts omitted. [Figure 8] A plan view showing the configuration of the head body according to the embodiment, with some parts omitted. [Figure 9] An explanatory diagram showing the configuration of the inclined surface of the actuator of the head body according to the embodiment. [Figure 10]A flowchart showing an example of a method for manufacturing a liquid dispensing head according to the embodiment. [Figure 11] An explanatory diagram showing the configuration of a liquid dispensing device using a liquid dispensing head according to the embodiment. [Modes for carrying out the invention]

[0009] Below, a liquid discharge head 1 and a liquid discharge device 2 using the liquid discharge head 1 according to an embodiment will be described with reference to Figures 1 to 12. Figure 1 is a perspective view showing the configuration of the liquid discharge head 1 according to the first embodiment, and Figure 2 is a bottom view showing the configuration of the liquid discharge head 1. Figure 3 is a bottom view showing the configuration of the liquid discharge head 1 with the nozzle plate 114 omitted. Figure 4 is a perspective view showing the configuration of the head body 11 of the liquid discharge head 1 with a part of the nozzle plate 114 cut out, and Figure 5 is a cross-sectional view showing the configuration of the head body 11. Figure 6 is a plan view showing the configuration of the substrate 111, actuator 113 and electrode 117 of the head body 11. Figure 7 is an enlarged perspective view showing the configuration of the substrate 111, actuator 113 and electrode 117 of the head body 11, and Figure 8 is an enlarged plan view showing the configuration of the substrate 111, actuator 113 and electrode 117 of the head body 11.

[0010] Figure 9 shows the configuration of the inclined surface 1134 of the actuator 113, and is an explanatory diagram showing the relationship between the inclined surface 1134 and the parallel light LA ​​and reflected light LB in photolithography. Figure 10 is a flowchart showing an example of how to manufacture the liquid discharge head 1, specifically an example of forming the electrode 117 and liquid-proof wall 1135 of the head body 11. Figure 11 is an explanatory diagram showing the configuration of the liquid discharge device 2 using the liquid discharge head 1. Note that in each figure, the configuration has been enlarged, reduced, or omitted as appropriate for explanatory purposes.

[0011] The liquid ejection head 1 is a shear-mode inkjet head provided in a liquid ejection device 2, such as the inkjet recording device shown in Figure 12. The liquid ejection head 1 is provided in a head unit 2130, which includes a supply tank 2132 as a liquid storage section provided in the liquid ejection device 2.

[0012] The liquid ejection head 1 is supplied with ink as the liquid stored in the supply tank 2132. Note that the liquid ejection head 1 may be a non-circulating head that does not circulate the ink, or may be a circulating head that circulates the ink. In the present embodiment, the liquid ejection head 1 will be described using an example of a non-circulating head. Further, the liquid ejection head 1 is connected to a temperature control device 2116 provided in the liquid ejection device 2, and a temperature control liquid (temperature control water) for controlling the temperature of the ink is supplied.

[0013] As shown in FIGS. 1 to 4, the liquid ejection head 1 includes a head 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 4-row integrated structure head having two sets of head bodies 11 each having a pair of actuators 113.

[0014] The head body 11 ejects liquid. As shown in FIGS. 3 to 6, 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 communicating with the plurality of pressure chambers 1131 of the actuator 113.

[0015] Further, the head body 11 has electrodes 117 for driving the plurality of pressure chambers 1131 of the actuator 113 on the substrate 111 and the actuator 113. The head body 11 is configured by covering a head substrate on which a pair of actuators 113 are arranged on the substrate 111 and electrodes 117 including wiring patterns are formed on the substrate 111 and the actuator 113 with the frame member 112 and the nozzle plate 114.

[0016] In the example of this embodiment, the head body 11 has two actuators 113, and the common liquid chamber 116 having one first common liquid chamber 1161 and two second common liquid chambers 1162 will be described. The common liquid chamber 116 has, for example, a first common liquid chamber 1161 communicating with one opening of a plurality of pressure chambers 1131 of the actuator 113, a second common liquid chamber 1162 communicating with the other opening of the plurality of pressure chambers 1131 of the actuator 113, and a third common liquid chamber 1163 connecting both ends of the first common liquid chamber 1161 and both ends of the two second common liquid chambers 1162.

[0017] The substrate 111 is formed in a rectangular plate shape from, for example, a ceramic material. The substrate 111 is formed, for example, in a rectangular shape that is long in one direction. On one surface of the substrate 111, a wiring pattern that is part of the electrode 117 is formed. As a specific example, on one surface of the substrate 111, a wiring pattern that is part of a plurality of individual electrodes 118 and a wiring pattern that is part of a single common electrode 119, which will be described later, of the electrode 117 are formed. On one surface of the substrate 111, a pair of actuators 113 are provided side by side in the short side direction of the substrate 111. One surface of the substrate 111 is 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 ports 1112 are through holes that penetrate between both main surfaces of the substrate 111.

[0018] 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 at the center in the short side direction of the substrate 111. The supply port 1111 extends along the long side 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 long side direction of the actuator 113 and the long side 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.

[0019] The discharge port 1112 is an outlet for discharging ink from the common liquid chamber 116. Multiple discharge ports 1112 are provided, for example, two. The discharge ports 1112 are formed, for example, as elongated holes or round holes that are long in one direction. In this embodiment, the discharge ports 1112 are formed as elongated holes that are long in one direction. The opening area of ​​the discharge ports 1112 is smaller than the opening area of ​​the supply ports 1111. The two discharge ports 1112 are, for example, located opposite the first common liquid chamber 1161 and adjacent to each of the longitudinal ends of the supply ports 1111. The multiple discharge ports 1112 may be configured to be provided in, for example, two third common liquid chambers 1163, or they may be provided in the second common liquid chamber 1162.

[0020] The frame member 112 is fixed to one main surface of the substrate 111 with adhesive or the like. The frame member 112 surrounds the supply port 1111, the multiple discharge ports 1112, and the actuator 113 provided on the substrate 111. For example, the frame member 112 has a stepped structure.

[0021] For example, the frame member 112 is formed in a rectangular frame shape, thereby forming a long opening in one direction along the longitudinal direction of the frame member 112. A pair of actuators 113, a supply port 1111, and two discharge ports 1112 are arranged in the opening of the frame member 112.

[0022] A pair of actuators 113 are bonded to the mounting surface of the substrate 111. The pair of actuators 113 are arranged in two rows on the substrate 111, with the supply port 111 in between. The actuators 113 are formed in a plate shape that is long in one direction. The actuators 113 are placed within the opening of the frame member 112 and bonded to the main surface of the substrate 111.

[0023] As shown in Figures 3, 4, and 6, the actuator 113 is formed to be elongated in one direction. The actuator 113 has a plurality of pressure chambers 1131 arranged at equal intervals in the longitudinal direction, and a plurality of air chambers 1132 arranged at equal intervals in the longitudinal direction and positioned between adjacent pressure chambers 1131. In other words, the actuator 113 has a plurality of pressure chambers 1131 and a plurality of air chambers 1132 arranged alternately along the longitudinal direction.

[0024] The side of the actuator 113 opposite to the substrate 111 is bonded to the nozzle plate 114. The actuators 113 are arranged at equal intervals in the longitudinal direction, and multiple grooves are formed along the short direction, which is perpendicular to the longitudinal direction. The multiple grooves form multiple pressure chambers 1131 and multiple air chambers 1132. That is, the multiple grooves include multiple pressure grooves that constitute multiple pressure chambers 1131 and multiple air grooves that constitute multiple air chambers 1132. In other words, the actuator 113 has multiple piezoelectric elements 1133, which are driving elements that constitute partitions forming grooves between them, arranged at equal intervals in the longitudinal direction. The multiple piezoelectric elements 1133 form multiple pressure chambers 1131 and multiple air chambers 1132 between adjacent piezoelectric elements 1133, and the volume of the pressure chambers 1131 is changed when a driving voltage is applied.

[0025] As shown in Figures 5, 7 to 9, the actuator 113 has a width in the short-side direction that gradually increases from the top side toward the substrate 111 side. In other words, the cross-sectional shape of the section of the actuator 113 along the direction perpendicular to the longitudinal direction (short-side direction) is formed as a trapezoid. That is, the actuator 113 has inclined surfaces 1134 that are inclined on the sides in the short-side direction. Here, the inclined surfaces 1134 are the two sides of the actuator 113 in the short-side direction. In other words, the actuator 113 has two inclined surfaces 1134 that extend along the longitudinal direction. The two inclined surfaces 1134 are the first inclined surface 11341, which is one of the inclined surfaces 1134, and the second inclined surface 11342, which is the other of the inclined surfaces 1134.

[0026] As shown in Figure 9, of the two inclined surfaces 1134, the inclination of the first inclined surface 11341 is gentler than the inclination of the second inclined surface 11342. That is, the inclination angle θA of the first inclined surface 11341 with respect to the main surface of the substrate 111 is smaller than the inclination angle θB of the second inclined surface 11342 with respect to the main surface of the substrate 111.

[0027] For example, the inclination angle θA of the first inclined surface 11341 is 45° or less and greater than 0°. A preferred example of the first inclined surface 11341 is 45°.

[0028] For example, the inclination angle θB of the second inclined surface 11342 is greater than 45° and less than 90°. The upper limit of the inclination angle θB of the second inclined surface 11342 is an angle that is less than 90° and allows a portion of the electrode 117 to be formed on the second inclined surface 11342.

[0029] As shown in Figures 5 and 9, the pair of actuators 113 are mounted on the substrate 111 with their second inclined surfaces 11342 adjacent to each other in the short direction. The direction in which the pair of actuators 113 are aligned is the short direction of the substrate 111.

[0030] As shown in Figures 7 and 8, a wiring pattern that will become part of the multiple individual electrodes 118 of electrode 117 is formed on the first inclined surface 11341. Also, as shown in Figure 8, a wiring pattern that will become part of the common electrode 119 is formed on the second inclined surface 11342.

[0031] As a specific example, the actuator 113 is formed from a laminated piezoelectric member, which consists of two rectangular plates of piezoelectric material, each elongated in one direction, bonded together facing each other so that their polarization directions are opposite. Here, the piezoelectric material is, for example, PZT (lead zirconate titanate). The actuator 113 is bonded to the mounting surface of the substrate 111, for example, by a thermosetting epoxy adhesive. The actuator 113 is then formed into an inclined surface 1134 by, for example, machining. In addition, the substrate 111 and the actuator 113 are polished, for example, by polishing, so that the surfaces on which the multiple individual electrodes 118 and the common electrode 119 of the electrode 117 are patterned are polished, forming 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 by, for example, machining, which creates multiple grooves that form multiple pressure chambers 1131 and multiple air chambers 1132, and piezoelectric elements (driving elements) 1133 that serve as side walls separating adjacent grooves.

[0032] Furthermore, wiring patterns that form part of multiple individual electrodes 118 and wiring patterns that form part of one or more common electrodes 119 are formed in multiple grooves and parts of the inclined surface 1134 of the actuator 113.

[0033] The pressure chamber 1131 deforms during printing or other operations by the liquid ejection head 1, thereby ejecting ink from the nozzle 1141. The pressure chamber 1131 has an inlet that opens into the first common liquid chamber 1161 and an outlet that opens into the second common liquid chamber 1162. Ink flows into the pressure chamber 1131 from the inlet and flows out from the outlet. The pressure chamber 1131 may also be configured so that ink flows in from both openings described as the inlet and outlet.

[0034] As shown in Figure 7, the air chamber 1132 is separated from the first common liquid chamber 1161 and the second common liquid chamber 1162 by sealing its inlet and outlet sides with a liquid-blocking wall 1135, which is a resin wall made of a photosensitive resin or the like. Specifically, the liquid-blocking wall 1135 of the air chamber 1132 is formed by injecting an ultraviolet-curing resin into the groove forming the air chamber 1132, and then irradiating the necessary parts, for example, both ends (the inlet and outlet sides of the groove), with ultraviolet light using a mask plate or the like. Such a liquid-blocking wall 1135 prevents ink from entering the air chamber 1132. The liquid-blocking wall 1135 is also formed on a common electrode 119 formed on the inner surface of the air chamber 1132 of the actuator 113. Furthermore, the air chamber 1132 is sealed by a nozzle plate 114, and no nozzle 1141 is placed there. Therefore, ink does not flow into the air chamber 1132.

[0035] As shown in Figures 4 and 5, the nozzle plate 114 is formed in a plate shape. The nozzle plate 114 is fixed to the main surface of the frame member 112 opposite to the substrate 111 with an adhesive or the like. 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 rows of nozzle rows 1142 in which the plurality of nozzles 1141 are arranged in one direction.

[0036] The first common liquid chamber 1161 is formed between the central sides of a pair of actuators 113, excluding both ends, and constitutes a flow path for ink 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.

[0037] The second common liquid chamber 1162 is formed between each actuator 113 and the frame member 112. The second common liquid chamber 1162 forms a flow path for ink from the third common liquid chamber 1163 to the other opening of the plurality of pressure chambers 1131. The second common liquid chamber 1162 extends along the longitudinal direction of the actuator 113.

[0038] The third common liquid chamber 1163 is adjacent to, for example, both longitudinal ends of the actuator 113. The third common liquid chamber 1163 connects the first common liquid chamber 1161 and the two second common liquid chambers 1162 at both longitudinal ends of the pair of actuators 113. The third common liquid chamber 1163 forms a flow path for some ink from the first common liquid chamber 1161 to the second common liquid chambers 1162 without passing through the multiple pressure chambers 1131 of each actuator 113.

[0039] The electrode 117 is an electrode film (metal film) formed in the form of a film from a metallic material. The electrode 117 is formed, for example, by a multilayer film. The electrode 117 has, for example, a plurality of individual electrodes 118 that drive each of the plurality of pressure chambers 1131, and one or more common electrodes 119 that drive the plurality of pressure chambers 1131 simultaneously.

[0040] As shown in Figures 6 to 8, the electrode 117 has a first electrode portion 1171 which is a conductive portion formed on the main 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 plurality of pressure chambers 1131 and plurality of air chambers 1132 of the actuator 113.

[0041] The first electrode portion 1171 is a wiring pattern (leader wire). The first electrode portion 1171 is formed by a multilayer film. The second electrode portion 1172 is formed on the inner surface of the grooves that form the pressure chamber 1131 and the air chamber 1132. The second electrode portion 1172 is formed, for example, by a multilayer film of the same layer as the first electrode portion 1171.

[0042] For example, electrode 117 includes a Ni sputtered film, an electroless Ni plating film, and an electrolytic metal plating film formed of a different metal (dissimilar metal) from the Ni sputtered film and the electroless Ni plating film. Electrode 117 may also have an electrolytic Ni plating film between the electroless Ni plating film and the electrolytic metal plating film. The electrolytic metal plating film is, for example, an Au plating film.

[0043] Multiple individual electrodes 118 apply individual drive voltages to multiple piezoelectric elements 1133, which are driving elements. Multiple individual electrodes 118 individually deform each pressure chamber 1131. The individual electrodes 118 are formed by wiring patterns formed on the substrate 111 and wiring patterns formed on the actuator 113. The individual electrodes 118 are wiring patterns formed by a first electrode portion 1171 and a second electrode portion 1172. Multiple individual electrodes 118 are connected to the circuit board 13.

[0044] As a specific example, as shown in Figures 7 and 8, multiple individual electrodes 118 are formed on the inner surface of each pressure chamber 1131, the first inclined surface 11341 of the actuator 113, and on the substrate 111. Specifically, the individual electrodes 118 are formed by the second electrode portion 1172 on the side surface of the piezoelectric element 1133 that forms the pressure chamber 1131, and on the bottom surface of the pressure chamber 1131 (pressure groove). In addition, the individual electrodes 118 are formed by the first electrode portion 1171 on the first inclined surface 11341 and the polished surface of the substrate 111. The individual electrodes 118 extend from inside the pressure chamber 1131 to the short-side end of the substrate 111, and their ends are positioned at the connection portion 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 element that forms the piezoelectric element 1133. For example, the individual electrodes 118 on the substrate 111 are covered on the lower side of the frame member 112 with an adhesive that adheres the frame member 112 to the substrate 111.

[0045] The common electrode 119 applies a driving voltage to multiple piezoelectric elements 1133. For example, the common electrode 119 applies the same driving voltage to all of the multiple piezoelectric elements 1133. The common electrode 119 deforms multiple pressure chambers 1131 simultaneously. 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 across the piezoelectric elements 1133 that form multiple air chambers 1132. The common electrode 119 is a wiring pattern formed by a single first electrode portion 1171 and multiple second electrode portions 1172. The common electrode 119 is connected to the circuit board 13. That is, the common electrode 119 is connected to the multiple air chambers 1132 via multiple second electrode portions 1172 from the first electrode portion 1171 connected to the circuit board 13.

[0046] As a specific example, as shown in Figure 8, the common electrode 119 is formed in areas that avoid the inner surfaces of each air chamber 1132, the inclined surfaces 1134 of the actuator 113, and the areas on the substrate 111 where the individual electrodes 118 are formed. Specifically, the common electrode 119 is formed by the second electrode portion 1172 on the side surfaces of the piezoelectric elements 1133 that form each air chamber 1132, and on the bottom surfaces of the air chambers 1132 (air grooves). The common electrode 119 is also provided by the first electrode portion 1171 on the second inclined surface 11342, extending from within each air chamber 1132 toward the center of the substrate 111, and is also formed on the polished surface of the substrate 111 between the pair of actuators 113. Furthermore, the common electrode 119 extends to the short-side end of the substrate 111, with its end positioned at the connection portion 1116 to which the circuit board 13 of the substrate 111 is connected. The common electrode 119 may also be formed on the inner circumferential surface of the supply port 1111 and the inner circumferential surface of the discharge port 1112.

[0047] In other words, the common electrode 119 is integrally provided on the second inclined surface 11342 of the actuator 113 and the inner surface of the multiple air chambers 1132, via the connection portion 1116 formed at the short-side end of the substrate 111, the area where the multiple individual electrodes 118 are not formed, and the short-side central part of the substrate 111 between the pair of actuators 113. Furthermore, a portion of the common electrode 119 provided in the area where the liquid-proof wall 1135 of the air chamber 1132 is provided is positioned between the surface of the liquid-proof wall 1135 and the surface of the air chamber 1132.

[0048] As shown in Figures 1, 4, and 5, the manifold unit 12 comprises a manifold 121, a top plate 122, an ink supply pipe 123, an ink discharge pipe 124, and a pair of temperature control pipes, namely a temperature-controlled water supply pipe 125 and a temperature-controlled water discharge pipe. The number of ink supply pipes 123, ink discharge pipes 124, temperature-controlled water supply pipes 125, and temperature-controlled water discharge pipes can be set as appropriate.

[0049] The manifold 121 is formed in the shape of a plate or a block. As shown in Figure 5, the manifold 121 includes a supply channel 1211 which is continuous with the supply port 1111 of the substrate 111 and forms a liquid supply channel, a discharge channel which is continuous with the discharge port 1112 of the substrate 111 and forms a liquid discharge channel, and a temperature control channel 1213 which forms a channel for a temperature control fluid.

[0050] One main surface of the manifold 121 is fixed to the main surface of the substrate 111. The 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. Furthermore, 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.

[0051] The supply channel 1211 is a channel formed in the manifold 121 by holes or grooves. The supply channel 1211 fluidly connects the ink supply pipe 123 and the supply port 1111 of the substrate 111.

[0052] The discharge channel is a channel formed in the manifold 121 by holes or grooves. The discharge channel fluidly connects the ink discharge pipe 124 and the discharge port 1112 of the substrate 111.

[0053] The temperature control channel 1213 is a channel formed in the manifold 121 by holes or grooves. The temperature control channel 1213 fluidly connects the temperature-controlled water supply pipe 125 and the temperature-controlled water discharge pipe.

[0054] Both ends of the temperature control channel 1213 are openings that connect to the temperature-controlled water supply pipe 125 and the temperature-controlled water discharge pipe, which are provided on one main surface of the manifold 121. The temperature control channel 1213 is also formed to allow heat exchange with the substrate 111 fixed to the manifold 121.

[0055] The top plate 122 is provided on the side of the manifold 121 opposite to the side on which the substrate 111 is provided. By covering the manifold 121, the top plate 122 seals the supply channel 1211, the discharge channel, and the temperature control channel 1213.

[0056] Furthermore, the top plate 122 has openings for connecting the pipes 123, 124, and 125, and for connecting the pipes 123, 124, and 125 and the flow paths 1211 and 1213.

[0057] The ink supply pipe 123 is connected to the supply channel 1211. The ink discharge pipe 124 is connected to the discharge channel. The temperature-controlled water supply pipe 125 and the temperature-controlled water discharge pipe are connected to the primary and secondary sides of the temperature-controlled channel 1213.

[0058] As shown in Figure 4, the circuit board 13 comprises a wiring film 131 with one end connected to a connection portion 1116 of the board 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.

[0059] The circuit board 13 drives the actuator 113 by applying a drive voltage to the wiring pattern of the actuator 113 using the driver IC 132, thereby increasing or decreasing the volume of the pressure chamber 1131 and ejecting droplets from the nozzle 1141.

[0060] The wiring film 131 is connected to a plurality of individual electrodes 118 and a common electrode 119. For example, the wiring film 131 is an ACF (anisotropic conductive film) fixed to the connection part of the substrate 111 by thermocompression or the like. Multiple wiring films 131 are provided for a single head body 11, for example. In this embodiment, two wiring films 131 are connected to a single actuator 113. The wiring film 131 is, for example, a COF (Chip on Film) on which a driver IC 132 is mounted.

[0061] The driver IC 132 is connected to a plurality of individual electrodes 118 and a common electrode 119 via a wiring film 131. Alternatively, the driver IC 132 may be connected to the plurality of individual electrodes 118 and the common electrode 119 by means other than the wiring film 131, such as ACP (anisotropic conductive paste), NCF (non-conductive film), and NCP (non-conductive paste).

[0062] The printed wiring board 133 is a PWA (Printing Wiring Assembly) on which various electronic components and connectors are mounted.

[0063] The cover 14 includes, for example, an outer casing 141 that covers the sides 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 nozzle plate 114 side of the pair of head bodies 11.

[0064] The outer casing 141 exposes, for example, the ink supply pipe 123, ink discharge pipe 124, temperature-controlled water supply pipe 125, and temperature-controlled water discharge pipe of the manifold unit 12, as well as the end of the circuit board 13, to the outside.

[0065] The mask plate 142 covers the portion of the pair of head bodies 11 excluding the multiple nozzles 1141 and the area around the multiple nozzles 1141 of the nozzle plate 114.

[0066] Next, as an example of a manufacturing method for the liquid dispensing head 1, an example of molding the electrodes 117 of the head body 11 will be explained using the flowchart shown in Figure 10.

[0067] First, a metal film is formed in predetermined areas of the substrate 111 and the actuator 113 (ACT1). As a specific example, first, a Ni sputtered film is formed in predetermined areas of the substrate 111 and the actuator 113 by sputtering. Here, the predetermined areas are the substrate 111, the first inclined surface 11341 and the second inclined surface 11342 of the actuator 113, and the inner surfaces of the plurality of piezoelectric elements 1133 (plural grooves) that constitute the plurality of pressure chambers 1131 and plurality of air chambers 1132 of the actuator 113.

[0068] Next, an electroless Ni plating film is formed on the Ni sputtered film using an electroless plating method. For example, the Ni sputtered film is used as a catalyst to form the electroless Ni plating film. Through these steps, a metal film consisting of the Ni sputtered film / electroless Ni plating film is formed in predetermined areas of the substrate 111 and the actuator 113.

[0069] Next, the metal film is patterned by photolithography (ACT2). The pattern of the metal film formed by photolithography is, for example, the same as the electrode patterns of the multiple individual electrodes 118 and the common electrode 119 formed on the substrate 111 and the actuator 113.

[0070] In the process of patterning the metal film using photolithography, parallel light LA ​​is irradiated from a direction perpendicular to the main surface of the substrate 111, as shown in Figure 9.

[0071] At this time, the parallel light LA ​​irradiated onto the first inclined surface 11341 is reflected by the first inclined surface 11341. Since the inclination angle θA of the first inclined surface 11341 with respect to the main surface of the substrate 111 is 45° or less, the sum of the incident angle and the reflected angle θC of the light reflected from the first inclined surface 11341 is 90° or less. Therefore, the reflected light LB from the first inclined surface 11341 does not irradiate onto the substrate 111. This prevents the individual electrodes 118 from becoming open.

[0072] Furthermore, the parallel light LA ​​irradiated onto the second inclined surface 11342 is reflected by the second inclined surface 11342. Since the inclination angle θB of the second inclined surface 11342 with respect to the main surface of the substrate 111 is greater than 45°, the sum of the incident angle and the reflected angle θD of the light reflected by the second inclined surface 11342 is greater than 90°. For this reason, there is a risk that the reflected light LB from the second inclined surface 11342 will irradiate the substrate 111.

[0073] However, the pair of actuators 113 are mounted on the substrate 111 in a orientation such that the second inclined surface 11342 is located towards the center in the direction in which the pair of actuators 113 are aligned. Therefore, when reflected light LB from the second inclined surface 11342 is irradiated onto the substrate 111, the reflected light LB is irradiated onto the substrate 111 between the pair of actuators 113 on which the common electrode 119 is formed. Since the wiring pattern of the common electrode 119 is formed over a wide area, even if the reflected light LB irradiates the area on the substrate 111 where the common electrode 119 is formed and some of the metal film is removed, the common electrode 119 will not become an open electrode.

[0074] Next, an electrolytic Au plating film is formed on the patterned metal film using an electrolytic plating method (ACT3). This forms a plurality of individual electrodes 118 and a common electrode 119.

[0075] Next, a liquid-proof wall 1135 is formed as a resin wall on the inlet and outlet sides of the air chamber 1132 (air groove) (ACT4). Through these steps, the electrodes 117 and liquid-proof wall 1135 of the head body 11 are formed. The substrate 111 is also sized after patterning or after the liquid-proof wall 1135 is formed. After these steps, one end of the circuit board 13 is connected to the connection part 1116 of the substrate 111, the frame member 112 is joined to the substrate, and the nozzle plate 114 is joined to the substrate 111, the frame member 112 and the actuator 113, thereby forming the head body 11.

[0076] The liquid discharge head 1 configured in this way has a first inclined surface 11341 and a second inclined surface 11342 in the short-side direction of the actuator 113, each having a different inclination angle with respect to the substrate 111. Here, the short-side direction of the actuator 113 is the direction in which the pair of actuators 113 are aligned, and also the short-side direction of the substrate 111. Furthermore, the inclination angle θB of the second inclined surface 11342 is greater than the inclination angle θA of the first inclined surface 11341. As a result, the width of the actuator 113 in the short-side direction and the width of the substrate 111 on which the pair of actuators 113 are provided can be reduced.

[0077] Furthermore, the inclination angle θA of the first inclined surface 11341 is set to 0 < θA ≤ 45°, and the inclination angle θB of the second inclined surface 11342 is set to 45° < θB < 90°. As a result, the sum of the incident angle and reflection angle θC of the parallel light LA ​​of the electrode 117 patterning reflected from the first inclined surface 11341 is 90° or less, and the sum of the incident angle and reflection angle θD of the light reflected from the second inclined surface 11342 is greater than 90°.

[0078] Therefore, it is possible to prevent the reflected light LB from the first inclined surface 11341 from irradiating the metal film forming the individual electrodes 118 on the substrate 111. In other words, it is possible to avoid unintended exposure of the area on the substrate 111 where the individual electrodes 118 are formed by the reflected light LB from the first inclined surface 11341. Therefore, the liquid discharge head 1 can prevent electrode opening of the individual electrodes 118.

[0079] Furthermore, since the common electrode 119 is connected to multiple air chambers 1132, it is integrally provided over a wide area of ​​the substrate 111. Therefore, the liquid discharge head 1 can prevent electrode opening of the common electrode 119 even when reflected light LB from the second inclined surface 11342 irradiates the metal film forming the common electrode 119 on the substrate 111.

[0080] According to the liquid discharge head 1 of the embodiment described above, the liquid discharge head 1 can reduce the size of the substrate 111 and actuator 113 without the electrodes becoming open by making the inclination angle θB of the second inclined surface 11342 on which the common electrode 119 is provided larger than the inclination angle θA of the first inclined surface 11341.

[0081] The inkjet recording device 2 having a liquid ejection head 1 will be described below with reference to Figure 11. The inkjet recording device 2 comprises a housing 2111, a media supply unit 2112, an image forming unit 2113, a media discharge unit 2114, a transport device 2115 which is a support device, a temperature control device 2116, a maintenance device 2117, and a control unit 2118. The inkjet recording device 2 also includes a temperature control device that adjusts the temperature of the ink supplied to the liquid ejection head 1.

[0082] The inkjet recording device 2 is an inkjet printer that performs image formation processing on paper P by transporting paper P, for example, as a recording medium to be ejected, along a predetermined transport path 2001 from the media supply unit 2112 through the image forming unit 2113 to the media ejection unit 2114, while ejecting a liquid such as ink.

[0083] The media supply unit 2112 includes a plurality of paper feed cassettes 21121. The image forming unit 2113 includes a support unit 2120 for supporting paper and a plurality of head units 2130 positioned opposite each other above the support unit 2120. The media discharge unit 2114 includes a paper output tray 21141.

[0084] The support unit 2120 includes a conveyor belt 21201 provided in a loop shape in a predetermined area where image formation is performed, a support plate 21202 that supports the conveyor belt 21201 from the back, and a plurality of belt rollers 21203 provided on the back of the conveyor belt 21201.

[0085] The head unit 2130 comprises a liquid ejection head 1 which is a plurality of inkjet heads, a plurality of supply tanks 2132 which are liquid tanks mounted on each liquid ejection head 1, a pump 2134 which supplies ink, and a connecting channel 2135 which connects the liquid ejection head 1 and the supply tanks 2132.

[0086] In this embodiment, the liquid ejection head 1 comprises four liquid ejection heads 1 for cyan, magenta, yellow, and black, and four supply tanks 2132 each containing ink of one of these colors. The supply tanks 2132 are connected to the liquid ejection head 1 by a connecting channel 2135.

[0087] Pump 2134 is a liquid transfer pump, for example, a piezoelectric pump. Pump 2134 is connected to the control unit 2118 and is driven and controlled by the control unit 2118.

[0088] The connecting channel 2135 includes a supply channel connected to the ink supply pipe 123 of the liquid ejection head 1. The connecting channel 2135 also includes a recovery channel connected to the ink discharge pipe 124 of the liquid ejection head 1. For example, if the liquid ejection head 1 is a non-circulating type, the recovery channel is connected to the maintenance device 2117, and if the liquid ejection head 1 is a circulating type, the recovery channel is connected to the supply tank 2132.

[0089] The transport device 2115 transports the paper P along a transport path 2001 from the paper feed cassette 21121 of the media supply unit 2112, through the image forming unit 2113, to the paper output tray 21141 of the media discharge unit 2114. The transport device 2115 comprises a plurality of guide plate pairs 21211 to 21218 and a plurality of transport rollers 21221 to 21228 arranged along the transport path 2001. The transport device 2115 supports the paper P so that it can move relative to the liquid discharge head 1.

[0090] The temperature control device 2116 includes a temperature-controlled water tank 21161, a temperature control circuit 21162 such as piping and tubes for supplying temperature-controlled water, a pump for supplying temperature-controlled water, and a temperature controller for adjusting the temperature of the temperature-controlled water. The temperature control device 2116 supplies temperature-controlled water from the temperature-controlled water tank 21161, which has been adjusted to a predetermined temperature by the temperature controller, to the temperature-controlled water supply pipe 125 of the liquid discharge head 1 via the temperature control circuit 21162 using water supplied by the pump. The temperature control device 2116 also recovers water discharged from the temperature-controlled water discharge pipe through the manifold unit 12 back into the temperature-controlled water tank 21161 via the temperature control circuit 21162. The temperature controller is, for example, a heater or a cooler. The temperature control device 2116 may also be configured to adjust the temperature of the ink supplied to the liquid discharge head 1.

[0091] The maintenance device 2117, for example, sucks up and recovers ink remaining on the outer surface of the nozzle plate 114 during maintenance. Furthermore, if the liquid discharge head 1 is a non-circulating type, the maintenance device 2117 recovers ink from within the head body 11 during maintenance. Such a maintenance device 2117 includes a tray or tank for storing the recovered ink.

[0092] The control unit 2118 includes a CPU 21181 as an example of a processor, a memory such as ROM (Read Only Memory) for storing various programs, RAM (Random Access Memory) for temporarily storing various variable data and image data, and an interface unit for inputting data from the outside and outputting data to the outside.

[0093] According to the liquid dispensing device 2 of the embodiment described above, the size of the substrate 111 and actuator 113 of the liquid dispensing head 1 can be reduced. Furthermore, because the size of the liquid dispensing head 1 can be reduced, the liquid dispensing device 2 offers improved flexibility in the placement of the liquid dispensing head 1 and also reduces the space required for the liquid dispensing head 1 to be placed.

[0094] It should be noted that the embodiments of the present invention are not limited to the configuration described above. For example, in the example described above, the liquid discharge head 1 was described as having a configuration comprising a pair of head bodies 11, but it is not limited to this, and may have a configuration comprising a single head body 11.

[0095] Furthermore, although the above example described a configuration in which the head body 11 has a pair of actuators 113, it is not limited to this, and a configuration with a single actuator 113 is also possible. Even with a single actuator 113, the liquid discharge head 1 can reduce the width of the substrate 111 and actuator 113 in the short-side direction without the electrodes becoming open by making the inclination angle θB of the second inclined surface 11342 larger than the inclination angle θA of the first inclined surface 11341 of the actuator 113.

[0096] Furthermore, although the above example described a configuration in which the inclination angle θA of the first inclined surface 11341 of the liquid discharge head 1 is 45° or less, the configuration is not limited to this. That is, the inclination angle θA of the first inclined surface 11341 on which the individual electrodes 118 are formed is smaller than the inclination angle of the second inclined surface 11342 on which the common electrode 119 is formed, and the angle can be any other angle as long as the reflected light LB during photolithography exposure does not irradiate the area on the substrate 111 on which the individual electrodes 118 are patterned. In other words, if the reflected light LB of the first inclined surface 11341 irradiates the area of ​​the substrate 111 to be sized, the individual electrodes 118 will not become electrode open. However, considering the reduction of the width in the short-side direction of the substrate 111 and actuator 113, the formation of the electrode 117, the management of the reflected light LB, etc., it is preferable that the inclination angle θA of the first inclined surface 11341 is 45° or an angle slightly smaller than 45°.

[0097] According to at least one embodiment described above, the liquid discharge head can reduce the size of the substrate and actuator without the electrodes becoming open by making the inclination angle of the second inclined surface on which the common electrode is provided larger than the inclination angle of the first inclined surface.

[0098] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. The following is a description equivalent to the invention described in the original claims of this application. [1] A circuit board and An actuator provided on the substrate, having a first inclined surface that is elongated in one direction and extends along the longitudinal direction, a second inclined surface that extends along the longitudinal direction and has a larger inclination angle than the first inclined surface, and a plurality of pressure chambers that extend in the short direction, A plurality of individual electrodes formed on the substrate and the first inclined surface, each driving the plurality of pressure chambers, A common electrode formed on the substrate and the second inclined surface, which drives the plurality of pressure chambers, A liquid dispensing head equipped with a liquid dispensing head. [2] The first inclined surface has an inclination angle of 45° or less with respect to the surface of the substrate on which the actuator is provided. The liquid discharge head according to [1], wherein the second inclined surface has an inclination angle greater than 45° with respect to the surface on which the actuator is provided on the substrate. [3] The first inclined surface has a sum of the angle of incidence and the angle of reflection of light by photolithography that forms the plurality of individual electrodes and the common electrode, which is 90° or less. The liquid discharge head according to [2], wherein the second inclined surface is such that the sum of the angle of incidence and the angle of reflection of the light is greater than 90°. [4] The actuators are provided in pairs on the substrate in the short direction, The second inclined surfaces of the pair of actuators are adjacent in the short direction to the liquid discharge heads described in [1]. [5] The liquid discharge head according to any one of [1] to [4], wherein the actuator has a plurality of air chambers arranged alternately with the plurality of pressure chambers. [Explanation of Symbols]

[0099] 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 board, 141…Outer casing, 142…Mask plate, 1111…Supply port, 1112…Discharge port, 1116…Connection part, 1131…Pressure chamber, 1132…Air chamber, 1133…Piezoelectric element (driving element), 1134…Inclined surface, 1135…Liquid barrier, 1141…Nozzle, 1142…Nozzle row, 1161…First common liquid chamber, 1162…Second common liquid chamber, 1163…Third common liquid chamber, 1171…First electrode section, 1172…Second electrode section, 1211…Supply channel, 1213…Temperature control channel, 11341…First inclined surface, 1134 2...Second inclined surface, 2001...Conveyor path, 2111...Housing, 2112...Media supply unit, 2113...Image forming unit, 2114...Media discharge unit, 2115...Conveyor device, 2116...Temperature control device, 2117...Maintenance device, 2118...Control unit, 2120...Support unit, 2130...Head unit, 2132...Supply tank, 2134...Pump, 2135...Connecting channel, 21121...Paper feed cassette, 21141...Paper output tray, 21181...CPU, 21201...Conveyor belt, 21202...Support plate, 21203...Belt roller, 2 1211... 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... Conveyor roller, 21222... Conveyor roller, 21223... Conveyor roller, 21224... Conveyor roller, 21225... Conveyor roller, 21226... Conveyor roller, 21227... Conveyor roller, 21228... Conveyor roller, P... Paper.

Claims

1. circuit board and An actuator provided on the substrate and formed to be elongated in the longitudinal direction of the substrate, the actuator having a first inclined surface extending along the longitudinal direction, a second inclined surface extending along the longitudinal direction and having a larger inclination angle than the first inclined surface, and a plurality of pressure chambers extending in the short direction, A plurality of individual electrodes formed on the substrate and the first inclined surface, each driving the plurality of pressure chambers, A common electrode formed on the substrate and the second inclined surface, which drives the plurality of pressure chambers, Equipped with, The first inclined surface has an inclination angle of 45° or less with respect to the surface of the substrate on which the actuator is provided. The second inclined surface is a liquid dispensing head in which the inclination angle of the substrate with respect to the surface on which the actuator is provided is greater than 45°.

2. The first inclined surface has a sum of the angle of incidence and the angle of reflection of light obtained by photolithography that forms the plurality of individual electrodes and the common electrode, which is 90° or less. The liquid dispensing head according to claim 1, wherein the second inclined surface has a sum of the angle of incidence and the angle of reflection of the light that is greater than 90°.

3. The actuators are provided in pairs on the substrate in the short direction, The liquid discharge head according to claim 1, wherein the second inclined surfaces of the pair of actuators are adjacent in the short direction.

4. The liquid discharge head according to any one of claims 1 to 3, wherein the actuator has a plurality of air chambers arranged alternately with the plurality of pressure chambers.

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