HEAD CHIP, LIQUID JET HEAD, LIQUID JET RECORDING APPARATUS, AND METHOD OF MANUFACTURING HEAD CHIP

Abstract

To provide a head chip which inhibits short circuits of an electrode from being caused by an ink to maintain excellent discharge performance over a long time, and to provide a liquid jet head, a liquid jet recording device, and a manufacturing method of the head chip.SOLUTION: A head chip 50 according to one embodiment of the disclosure includes an actuator plate 53, a cover plate 54, and an intermediate plate 52. In the actuator plate 53, open ports 53a, 90aA which allow the interior and the exterior of a non-discharge channel 76A to communicate with each other are formed at both end parts in a Y direction of a non-jet channel 76. In the actuator plate 53, open ports 53b, 90aB which allow the interior and the exterior of a non-discharge channel 76B to communicate with each other are formed at both end parts in the Y direction of the non-discharge channel 76.SELECTED DRAWING: Figure 10

Description

[Technical field]

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

[0002] An inkjet head mounted on an inkjet printer ejects ink onto a recording medium through a head chip mounted on the inkjet head. The head chip includes an actuator plate in which ejection channels and non-ejection channels are alternately formed, and a nozzle plate joined to the actuator plate. In the actuator plate, electrodes are formed on the inner surfaces of the ejection channels and non-ejection channels, respectively. In the head chip, the volume of the ejection channel changes depending on the voltage applied to the electrode, causing the ink in the ejection channel to be ejected through a nozzle hole formed in a nozzle plate.

[0003] For example, the following Patent Documents 1 and 2 disclose a configuration in which an insulating protective film that covers the electrodes is formed on the inner surface of the ejection channel. This configuration is thought to be able to prevent the electrodes from shorting out through the ink in the ejection channel even when conductive ink is used. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-131175 A [Patent Document 2] JP 2017-136724 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in a head chip, there is a possibility that conductive ink may flow from inside the ejection channels into the non-ejection channels through voids in the actuator plate or through joints between the actuator plate and other members. However, in the conventional configuration, there is still room for improvement in terms of proactively forming a protective film on the inner surface of the non-ejection channel. If ink flows into the non-ejection channel, there is a possibility that the electrodes formed on the inner surface of the non-ejection channel will be short-circuited via the ink.

[0006] The present disclosure provides a head chip, a liquid jet head, a liquid jet recording apparatus, and a method for manufacturing the head chip, which are capable of suppressing short-circuiting of electrodes due to ink and maintaining excellent ejection performance for a long period of time. [Means for solving the problem]

[0007] In order to solve the above problems, the present disclosure employs the following aspects. (1) A head chip according to one aspect of the present disclosure includes an actuator plate in which a first channel region in which first ejection channels and first non-ejection channels extending in a first direction are arranged in a second direction intersecting the first direction, and a second channel region in which second ejection channels and second non-ejection channels extending in the first direction are arranged in the second direction, are arranged side by side in the first direction, a first liquid flow path communicating with the first ejection channels, and a second liquid flow path communicating with the second ejection channels, and a cover plate superimposed on the actuator plate, a first communication hole communicating with the first ejection channels at a center portion in the first direction, and a second liquid flow path communicating with the second ejection channels at a center portion in the first direction. and a communication plate superimposed on the actuator plate on the opposite side to the cover plate, the communication plate having a second communication hole communicating with the first ejection channel, the first non-ejection channel, the second ejection channel and the second non-ejection channel are each formed with a protective film, and in the actuator plate, first openings are formed at both ends of the first non-ejection channel in the first direction, connecting the inside and outside of the first non-ejection channel, and in the actuator plate, second openings are formed at both ends of the second non-ejection channel in the first direction, connecting the inside and outside of the second non-ejection channel.

[0008] According to this aspect, a protective film can be effectively formed on the inner surface of the first non-ejection channel by introducing a material for forming the protective film into the first non-ejection channel through first openings formed at both ends of the first non-ejection channel, and a protective film can be effectively formed on the inner surface of the second non-ejection channel by introducing a material for forming the protective film into the second non-ejection channel through second openings formed at both ends of the second non-ejection channel. As a result, it is possible to prevent the electrodes formed on the inner surfaces of the non-ejection channels from being short-circuited due to liquid or the like that has entered the non-ejection channels.

[0009] (2) In the head chip of the above aspect (1), the first opening includes a first inner opening located at an end of the first non-ejection channel on the second channel region side in the first direction, and a first outer opening located at an end of the first non-ejection channel opposite the second channel region side in the first direction, and the second opening includes a second inner opening located at an end of the second non-ejection channel on the first channel region side in the first direction, and a second outer opening located at an end of the second non-ejection channel opposite the first channel region side in the first direction, and it is preferable that a common groove extending in the second direction is formed in a boundary portion of the actuator plate and the communicating plate located between the first channel region and the second channel region in the first direction, connecting the first inner openings of the multiple first non-ejection channels and the second inner openings of the multiple second non-ejection channels. According to this aspect, the material for forming the protective film is introduced from the common groove through each of the inner openings into each of the non-ejection channels, which makes it possible to form the protective film more efficiently than when the material for forming the protective film is introduced individually into each of the non-ejection channels through each of the inner openings.

[0010] (3) In the head chip according to the above aspect (2), it is preferable that the cover plate is formed with a communication groove that communicates with the common groove. According to this aspect, the pressure loss in the space leading to each opening can be reduced, so that the material for forming the protective film can be efficiently introduced into the non-ejection channel through each inner opening.

[0011] (4) In the head chip of the above aspect (3), it is preferable that the width of the communicating groove in the first direction is wider than that of the common groove, and that the communicating groove communicates with the first inner opening and the second inner opening from the opposite side of the actuator plate to the communicating plate. According to this aspect, the material for forming the protective film that has passed through the common groove and entered the communicating groove is introduced into each non-ejection channel through each inner opening from the side of the actuator plate opposite the communicating plate. This allows the material for forming the protective film to be introduced directly into each non-ejection channel through the common groove or indirectly into each non-ejection channel through the communicating groove. As a result, the protective film can be efficiently formed on the inner surface of the non-ejection channel.

[0012] (5) In the head chip of aspect (3) or (4) above, it is preferable that the cover plate comprises a first common flow path collectively connected to a plurality of the first liquid flow paths, and a second common flow path collectively connected to a plurality of the second liquid flow paths, and a portion of the cover plate located between the first liquid flow path and the second common flow path separates the first common flow path and the second common flow path, and forms a beam portion extending in the second direction. According to this aspect, the beam portion makes it easier to ensure the strength of the cover plate. Therefore, when bonding the actuator plate and the cover plate, a bonding load can be effectively applied between the actuator plate and the cover plate. As a result, the actuator plate and the cover plate can be reliably bonded to each other, and ink leakage through the gap between the actuator plate and the cover plate can be suppressed.

[0013] (6) In the head chip according to the above aspect (5), the communicating groove is formed in the beam portion, It is preferable that the width of the communicating groove in the first direction is narrower than the width of the beam portion in the first direction. According to this aspect, by forming the communicating grooves in the beam portion, it is easy to ensure the depth of the communicating grooves, so that the source gas for the protective film can be efficiently introduced into the non-ejection channels through the respective openings. Moreover, since the width of the communication groove in the first direction is narrower than the width of the beam portion in the first direction, the portion of the beam portion located on the outer side of the communication groove constitutes a pressure-receiving area. The pressure-receiving area functions as a pressure-receiving surface that receives the load acting between the actuator plate and the cover plate when the actuator plate and the cover plate are bonded together. This makes it possible to effectively apply a bonding load between the actuator plate and the cover plate. As a result, it is possible to suppress leakage of ink between the actuator plate and the cover plate.

[0014] (7) In the head chip of aspect (6) above, it is preferable that the communicating groove, the first common flow path, and the second common flow path overlap in the overlapping direction in which the actuator plate and the cover plate are overlapped. According to this aspect, since it is easy to ensure the depth of the communicating groove, the source gas for the protective film can be efficiently introduced into the non-ejection channel through each opening.

[0015] (8) In a head chip of any of aspects (2) to (7) above, it is preferable that the first non-ejection channel comprises a first extension portion extending in the first direction and a first cut-up portion whose groove depth gradually becomes shallower from the first extension portion toward the second channel region in the first direction, and the second non-ejection channel comprises a second extension portion extending in the first direction and a second cut-up portion whose groove depth gradually becomes shallower from the second extension portion toward the first channel region in the first direction, and that the first cut-up portion crosses the common groove in the first direction and a portion communicating with the common groove constitutes the first inner opening, and that the second cut-up portion crosses the common groove in the first direction and a portion communicating with the common groove constitutes the second inner opening. According to this aspect, it is easier to ensure the opening area of ​​the inner opening compared to when the common groove communicates with the end of the raised portion, and this makes it possible to efficiently introduce the material for forming the protective film into the non-ejection channels through each inner opening.

[0016] (9) A liquid jet head according to this aspect includes the head chip according to any one of the above aspects (1) to (7). According to this aspect, since the head chip according to any one of the above aspects is provided, short-circuiting of electrodes due to liquid and the like can be suppressed, and excellent ejection performance can be maintained for a long period of time.

[0017] (10) A liquid jet recording apparatus according to this aspect includes the liquid jet head according to the above aspect (9). According to this aspect, since the liquid jet head according to the above aspect is provided, short-circuiting of electrodes caused by liquid and the like can be suppressed, and excellent jetting performance can be maintained for a long period of time.

[0018] (11) A method for manufacturing a head chip according to one aspect of the present disclosure, in which a material for forming the protective film is introduced into the non-ejection channels through the openings, includes an actuator plate in which ejection channels extending in a first direction and non-ejection channels are arranged in a second direction intersecting the first direction, a cover plate having a liquid flow path communicating with the ejection channels and overlaid on the actuator plate, and a communication plate having a communication hole communicating with the ejection channel at a center in the first direction and overlaid on the actuator plate on the opposite side of the cover plate, wherein in the actuator plate, openings are formed at both ends of the non-ejection channels in the first direction to communicate between the inside and the outside of the non-ejection channels, and the method includes a protective film formation process for forming a protective film on the inner surfaces of the ejection channels and the inner surfaces of the non-ejection channels, and the protective film formation process includes introducing the material for forming the protective film into the ejection channels through the liquid flow path and the communication hole, and introducing the material for forming the protective film into the non-ejection channels through the openings.

[0019] According to the present aspect, by introducing a material for forming a protective film into the ejection channel through the liquid flow path and the communicating hole, and by introducing the material for forming the protective film into the non-ejection channel through the open hole, a protective film can be effectively formed on the inner surface of the ejection channel and the inner surface of the non-ejection channel. As a result, it is possible to prevent the electrodes formed on the inner surfaces of the ejection channels and non-ejection channels from being short-circuited due to liquid or the like entering the ejection channels or non-ejection channels. Effect of the Invention

[0020] According to one aspect of the present disclosure, short-circuiting of electrodes due to liquid can be suppressed, and excellent ejection performance can be maintained for a long period of time. [Brief description of the drawings]

[0021] [Figure 1] 1 is a schematic configuration diagram of an inkjet printer according to a first embodiment. [Diagram 2] FIG. 2 is a schematic configuration diagram of an inkjet head and an ink circulation mechanism according to the first embodiment. [Diagram 3] 2 is a perspective view of the head chip from the -Z side in a state in which the nozzle plate according to the first embodiment is removed. FIG. [Figure 4] FIG. 2 is an exploded perspective view of the head chip according to the first embodiment. [Diagram 5] FIG. 4 is a bottom view of the actuator plate according to the first embodiment. [Figure 6] 6 is a cross-sectional view corresponding to line VI-VI in FIG. 5. [Figure 7] 7 is a cross-sectional view corresponding to the line VII-VII in FIG. 5. [Figure 8] FIG. 8 is an enlarged view of part VIII in FIG. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] FIG. 2 is an enlarged cross-sectional view of a plate assembly according to the first embodiment. [Figure 11] FIG. 11 is an enlarged cross-sectional view of a head chip according to a second embodiment. [Figure 12] FIG. 11 is an enlarged cross-sectional view of a head chip according to another configuration of the second embodiment. [Figure 13] FIG. 11 is an enlarged cross-sectional view of a head chip according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment according to the present disclosure will be described with reference to the drawings. In the embodiments and modified examples described below, the same reference numerals may be used to designate corresponding configurations, and the description may be omitted. In the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," not only strictly indicate such arrangements, but also indicate a state in which the components are relatively displaced with an angle or distance to an extent that allows a tolerance or the same function to be obtained. In the following embodiment, an inkjet printer (hereinafter, simply referred to as a printer) that uses ink (liquid) to record on a recording medium will be taken as an example for description. In the drawings used in the following description, the scale of each component is appropriately changed so that each component is of a recognizable size.

[0023] (First embodiment) [Printer 1] FIG. 1 is a schematic diagram of a printer 1. As shown in FIG. 1, a printer (liquid jet recording apparatus) 1 of this embodiment includes a pair of transport mechanisms 2, 3, an ink tank 4, an inkjet head (liquid jet head) 5, an ink circulation mechanism 6, and a scanning mechanism .

[0024] In the following description, an X, Y, Z Cartesian coordinate system is used as necessary. In this case, the X direction (second direction) coincides with the transport direction (sub-scanning direction) of the recording medium P (e.g., paper, etc.). The Y direction (first direction) coincides with the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction indicates the height direction (gravity direction) perpendicular to the X and Y directions. In the following description, the X, Y, and Z directions are described with the arrows on the figures as the plus (+) side and the opposite side to the arrows as the minus (-) side. In this embodiment, the +Z side corresponds to the upward direction of gravity, and the -Z side corresponds to the downward direction of gravity.

[0025] The transport mechanisms 2 and 3 transport the recording medium P to the +X side. The transport mechanisms 2 and 3 each include a pair of rollers 11 and 12 extending in the Y direction, for example. The ink tanks 4 each contain four colors of ink, for example, yellow, magenta, cyan, and black. Each inkjet head 5 is configured to be able to eject the four colors of ink, yellow, magenta, cyan, and black, respectively, according to the connected ink tank 4. The ink contained in the ink tank 4 may be either conductive ink or non-conductive ink.

[0026] FIG. 2 is a schematic diagram of the ink-jet head 5 and the ink circulation mechanism 6. As shown in FIG. 1 and 2, the ink circulation mechanism 6 circulates ink between the ink tank 4 and the inkjet head 5. Specifically, the ink circulation mechanism 6 includes a circulation flow path 23 having an ink supply pipe 21 and an ink discharge pipe 22, a pressure pump 24 connected to the ink supply pipe 21, and a suction pump 25 connected to the ink discharge pipe 22.

[0027] The pressure pump 24 pressurizes the inside of the ink supply pipe 21, and sends ink to the inkjet head 5 through the ink supply pipe 21. As a result, the ink supply pipe 21 side relative to the inkjet head 5 is under positive pressure. The suction pump 25 reduces the pressure inside the ink discharge tube 22 and sucks ink from the inkjet head 5 through the ink discharge tube 22. This creates a negative pressure on the ink discharge tube 22 side relative to the inkjet head 5. By driving the pressure pump 24 and the suction pump 25, the ink can be circulated between the inkjet head 5 and the ink tank 4 through the circulation flow path 23.

[0028] The scanning mechanism 7 causes the inkjet head 5 to scan back and forth in the Y direction. The scanning mechanism 7 includes a guide rail 28 extending in the Y direction, and a carriage 29 movably supported by the guide rail 28.

[0029] <Inkjet head 5> 1, the inkjet head 5 is mounted on a carriage 29. In the illustrated example, a plurality of inkjet heads 5 are mounted side by side in the Y direction on one carriage 29. The inkjet head 5 includes a head chip 50 (see FIG. 3), an ink supply unit (not shown) that connects the ink circulation mechanism 6 and the head chip 50, and a control unit (not shown) that applies a drive voltage to the head chip 50.

[0030] <Head chip 50> Fig. 3 is a perspective view of head chip 50 seen from the -Z side with nozzle plate 51 removed. Fig. 4 is an exploded perspective view of head chip 50. The head chip 50 shown in Figs. 3 and 4 is a so-called circulation type side shoot type head chip 50 that circulates ink between the ink tank 4 and ejects ink from the center of an ejection channel 75 (described later) in the extension direction (Y direction). The head chip 50 includes a nozzle plate 51 (see Fig. 4), an intermediate plate (communication plate) 52, an actuator plate 53, and a cover plate 54. The head chip 50 is configured such that the nozzle plate 51, the intermediate plate 52, the actuator plate 53, and the cover plate 54 are stacked in this order in the Z direction. In the following description, the direction from the nozzle plate 51 toward the cover plate 54 (+Z side) in the Z direction may be described as the back side, and the direction from the cover plate 54 toward the nozzle plate 51 (-Z side) may be described as the front side.

[0031] The actuator plate 53 is made of a piezoelectric material such as PZT (lead zirconate titanate). The actuator plate 53 is a so-called chevron substrate formed by laminating two piezoelectric plates whose polarization directions are different in the Z direction. However, the actuator plate 53 may be a so-called monopole substrate whose polarization direction is one direction over the entire Z direction.

[0032] FIG. 5 is a bottom view of the actuator plate 53. As shown in FIG. As shown in FIGS. 4 and 5, a plurality of (for example, four) channel rows 61-64 are formed on the actuator plate 53. The channel rows 61-64 extend in the X direction and are arranged at intervals in the Y direction. In this embodiment, the channel rows 61-64 are a first channel A row (first channel region) 61, a first channel B row (second channel region) 62, a second channel A row (first channel region) 63, and a second channel B row (second channel region) 64. The first channel A row 61 and the first channel B row 62 constitute a first channel group 66. The second channel A row 63 and the second channel B row 64 constitute a second channel group 67.

[0033] 5, in the actuator plate 53, a group separation groove 71 is formed in a portion located between each of the channel groups 66, 67. The group separation groove 71 penetrates the actuator plate 53 in the Z direction and extends in the X direction. The group separation groove 71 separates each of the channel groups 66, 67. The head chip 50 has the same configuration on both sides of the group separation groove 71 in the Y direction. Therefore, in the following description, the configuration on the -Y side of the group separation groove 71 will be mainly described, and the description of the configuration on the +Y side will be omitted as appropriate.

[0034] In the actuator plate 53, a row separation groove 72 is formed in a portion located between the first channel A row 61 and the first channel B row 62, and in a portion located between the second channel A row 63 and the second channel B row 64. The row separation groove 72 penetrates the actuator plate 53 in the Z direction and extends in the X direction. The row separation groove 72 has a narrower width in the Y direction than the group separation groove 71. Note that each separation groove 71, 72 does not penetrate the actuator plate 53 in the X direction.

[0035] In the following, the configurations of the channel columns 61 to 64 will be described using the first channel column A 61 as an example. In the following description, among the channel columns 61 to 64, the configurations related to column A will be designated by the suffix A, and the configurations related to column B will be designated by the suffix B, and descriptions of the same or corresponding configurations in columns A and B may be omitted. In addition, when it is not necessary to distinguish between column A and column B in each of the channel columns 61 to 64, the suffix A or B will be omitted. The first channel A row 61 is formed on the actuator plate 53 on the opposite side (-Y side) of the row separation groove 72 from the group separation groove 71. The first channel A row 61 has ejection channels (first ejection channels) 75A filled with ink and non-ejection channels (first non-ejection channels) 76A not filled with ink. In a plan view seen from the Z direction, the channels 75A, 76A each extend linearly in the Y direction and are alternately arranged at intervals in the X direction. A portion of the actuator plate 53 located between the ejection channels 75A and the non-ejection channels 76A constitutes a drive wall 70 (see FIG. 4) that separates the ejection channels 75A and the non-ejection channels 76A in the X direction. In this embodiment, a configuration in which the channel extension direction coincides with the Y direction will be described, but the channel extension direction may cross the Y direction.

[0036] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 6, the discharge channel 75A is formed in a curved shape that is convex toward the front surface side in a side view seen from the X direction. The discharge channel 75 is formed, for example, by inserting a disk-shaped dicer from the rear surface side (+Z side) of the actuator plate 53. Specifically, the discharge channel 75A has cut-up portions 75a located at both ends in the Y direction and through portions 75b located between the cut-up portions 75a. Cut-up portion 75a has a uniform arc shape with a uniform radius of curvature that follows the radius of curvature of a dicer, for example, when viewed from the X direction. Cut-up portion 75a extends while curving toward the back side as it moves away from penetrating portion 75b in the Y direction. The through portion 75b passes through the actuator plate 53 in the Z direction.

[0037] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 7, the non-ejection channel 76A is adjacent to the ejection channel 75A in the X direction with the drive wall 70 sandwiched therebetween. The non-ejection channel 76A is formed, for example, by inserting a disk-shaped dicer from the back surface side (+Z side) of the actuator plate 53. The non-ejection channel 76A has a through portion (first extending portion) 76a and a cut-up portion (first cut-up portion) 76b. The through-holes 76a penetrate the actuator plate 53 in the Z direction. That is, the through-holes 76a are formed so that the groove depth in the Z direction is uniform. The through-holes 76a constitute the non-ejection channels 76 except for the +Y side end portions. The cut-up portion 76b constitutes the +Y side end of the non-ejection channel 76. When viewed from the X direction, the cut-up portion 76b is an arc shape with a uniform radius of curvature that extends following the radius of curvature of a dicer, for example. The cut-up portion 76b extends while curving toward the back side as it moves away from the through portion 76a in the Y direction.

[0038] 6 and 7, the dimension in the Y direction of the non-ejection channel 76A is longer than that of the ejection channel 75A. Specifically, in the non-ejection channel 76A, the -Y side end of the through portion 76a is located on the -Y side of the ejection channel 75A, and the +Y side end of the cut-up portion 76b is located on the +Y side of the ejection channel 75A.

[0039] As shown in FIG. 5, the first channel B row 62 is provided between the group separation groove 71 and the row separation groove 72 in the actuator plate 53. The first channel B row 62 has a configuration in which the ejection channels (second ejection channels) 75B and the non-ejection channels (second non-ejection channels) 76B are alternately arranged in the X direction, similar to the above-mentioned first channel A row 61. Specifically, the ejection channels 75B and the non-ejection channels 76B are arranged at a half pitch offset from the arrangement pitch of the ejection channels 75A and the non-ejection channels 76A. Therefore, in the inkjet head 5 of this embodiment, the ejection channels 75 of the first channel A row 61 and the first channel B row 62, and the non-ejection channels 76 of the first channel A row 61 and the first channel B row 62 are arranged in a staggered (alternate) manner. That is, between the adjacent channel rows 61 and 62, the ejection channels 75 and the non-ejection channels 76 face each other in the Y direction. However, between each of the channel rows 61, 62, the ejection channels 75 and the non-ejection channels 76 may be arranged to face each other in the Y direction. Note that each of the channel rows 61 to 64 may be arranged at a shift of 1 / 4 pitch from the arrangement pitch of the ejection channels 75A and the non-ejection channels 76A of the first channel A row 61.

[0040] In each of the channel rows 61 and 62, the discharge channels 75 are formed symmetrically with respect to the XZ plane that passes through the center of the row separation groove 72 in the Y direction. In each of the channel rows 61 and 62, the non-ejection channels 76 are formed symmetrically with respect to the XZ plane that passes through the center of the row separation groove 72 in the Y direction.

[0041] A portion of the actuator plate 53 located on the -Y side of the ejection channel 75A (through portion 75b) of the first channel A row 61 constitutes a first outer region 81. A portion of the actuator plate 53 located between a portion of the actuator plate 53 located on the +Y side of the ejection channel 75A of the first channel A row 61 and the row separation groove 72 constitutes a first inner region 82. A portion of the actuator plate 53 located between the row separation groove 72 and a portion located on the -Y side of the ejection channel 75B of the first channel B row 62 constitutes a second inner region 85. A portion of the actuator plate 53 located between the row separation groove 71 and a portion located on the +Y side of the ejection channel 75B of the first channel B row 62 constitutes a second outer region 86.

[0042] 7, in the first channel A row 61, the through-portion 76a of the non-ejection channel 76A penetrates the first outer region 81 in the Y direction and the Z direction. Of the through-portion 76a, the opening on the outer surface of the first outer region 81 constitutes an opening (first outer opening) 53a that connects the inside and outside of the non-ejection channel 76A.

[0043] FIG. 8 is an enlarged view of part VIII in FIG. As shown in FIG. 8, in the first channel A row 61, the cut-up portion 76b of the non-ejection channel 76A crosses the row separation groove 72 in the Y direction. Therefore, a part (the +Y side end) of the cut-up portion 76b reaches the second inner region 85 of the first channel B row 62. Specifically, the part of the cut-up portion 76b of the non-ejection channel 76A located in the first inner region 82 constitutes a communication portion 90A that communicates the through portion 76a and the row separation groove 72. The communication portion 90A is opened into the row separation groove 72 through an opening (first inner opening) 90aA. The part of the cut-up portion 76b of the non-ejection channel 76A that reaches the second inner region 85 constitutes a division portion 91A that is divided by the row separation groove 72.

[0044] 6, in the first channel B row 62, the through-portion 76a of the non-ejection channel 76B penetrates the second outer region 86 in the Y direction and the Z direction. Of the through-portion 76a, the opening on the outer surface of the second outer region 86 constitutes an opening (second outer opening) 53b that communicates between the inside and the outside of the non-ejection channel 76B.

[0045] As shown in FIG. 8, in the first channel B row 62, the cut-up portion (second cut-up portion) 76b of the non-ejection channel 76B crosses the row separation groove 72 in the Y direction. Therefore, a part (-Y side end) of the cut-up portion 76b reaches the first inner region 82 of the first channel A row 61. Specifically, the part of the cut-up portion 76b constituting the first channel B row 62 located in the second inner region 85 constitutes a communication portion 90B that communicates the through portion (second extension portion) 76a and the row separation groove 72. The communication portion 90B is opened into the row separation groove 72 through an opening 90aB. The part of the cut-up portion 76b of the non-ejection channel 76B that reaches the first inner region 82 constitutes a division portion 91B that is divided by the row separation groove 72. Note that the cut-up portion 76b does not have to cross the row separation groove 72 as long as it is configured to communicate at least into the row separation groove 72. In other words, the cut-up portion 76b may not have the dividing portion 91.

[0046] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 9, a common electrode 95 is formed on each of the inner surfaces of the driving wall 70 of the actuator plate 53 that face each ejection channel 75 (the surfaces of the inner surfaces of the ejection channels 75 that face each other in the X direction). The common electrode 95 is formed over the entire area in the Z direction on the inner surface of the ejection channel 75. The length of the common electrode 95 in the Y direction is equal to the length of the through portion 75b of the ejection channel 75 (equal to the opening length of the ejection channel 75 on the surface of the actuator plate 53).

[0047] 5, a plurality of common terminals 96 are formed on the surface of the actuator plate 53. The common terminals 96 are strip-shaped and extend parallel to each other along the Y direction. Each common terminal 96 is connected to a pair of common electrodes 95 at the opening edge of the corresponding ejection channel 75. Each common terminal 96 terminates within the corresponding outer region 81, 86.

[0048] 9, individual electrodes 97 are formed on the inner surfaces (surfaces of the non-ejection channels 76 facing each other in the X direction) of the driving wall 70 of the actuator plate 53. The individual electrodes 97 are formed on the inner surfaces of the non-ejection channels 76 over the entire area in the Z direction.

[0049] As shown in FIG. 5, individual terminals 98 are formed on the surfaces of the outer regions 81 and 86 at portions located outside the common terminal 96 in the Y direction. The individual terminals 98 are strip-shaped extending in the X direction. The individual terminals 98 connect the individual electrodes 97 that face each other in the X direction with the ejection channel 75 therebetween at the opening edges of the non-ejection channels 76 that face each other in the X direction with the ejection channel 75 therebetween. In addition, in the outer regions 81 and 86, a partition groove 99 is formed in a portion located between the common terminal 96 and the individual terminals 98. The partition groove 99 extends in the X direction in each of the outer regions 81 and 86. The partition groove 99 separates the common terminal 96 from the individual terminals 98. In addition, in FIG. 3, FIG. 4, etc., only a portion of the electrodes 95 and 97 and the terminals 96 and 98 are shown.

[0050] 6, a first flexible printed circuit board 100 is pressure-bonded to the surface of the first outer region 81. The first flexible printed circuit board 100 is connected to a common terminal 96 and individual terminals 98 corresponding to the first channel A row 61 on the surface of the first outer region 81. The first flexible printed circuit board 100 passes outside the actuator plate 53 and is drawn out to the +Z side.

[0051] A second flexible printed circuit board 101 is pressure-bonded to the surface of the second outer region 86. The second flexible printed circuit board 101 is connected to the common terminals 96 and individual terminals 98 corresponding to the first channel B row 62 on the surface of the second outer region 86. The second flexible printed circuit board 101 is drawn out to the +Z side through the group separation groove 71.

[0052] 9, a first protective film 110 is formed on the inner surface of the ejection channel 75. The first protective film 110 is formed over the entire inner surface of the ejection channel 75. The first protective film 110 covers the common electrode 95. The first protective film 110 suppresses contact between the common electrode 95 and ink, for example. It is sufficient that the first protective film 110 covers at least the common electrode 95 on the inner surface of the ejection channel 75.

[0053] A second protective film 111 is formed on the inner surface of the non-ejection channel 76. The second protective film 111 is formed over the entire inner surface of the non-ejection channel 76. The second protective film 111 covers the individual electrodes 97. The second protective film 111 suppresses, for example, contact between the individual electrodes 97 and ink. It is sufficient that the second protective film 111 covers at least the individual electrodes 97 on the inner surface of the non-ejection channel 76.

[0054] The protective films 110 and 111 include an organic insulating material such as a paraxylylene-based resin material (e.g., Parylene (registered trademark)). The protective film PF may be made of tantalum oxide (Ta2O5), silicon nitride (SiN), silicon carbide (SiC), silicon oxide (SiO2), diamond-like carbon, or the like, or may include at least one of these.

[0055] <Cover plate 54> 3 and 4, the cover plate 54 is adhered to the rear surface of the actuator plate 53 so as to close each of the channel groups 66, 67. In the cover plate 54, an inlet common ink chamber 120 and an outlet common ink chamber 121 are formed at positions corresponding to each of the channel rows 61 to 64. The inlet common ink chamber 120 is formed at a position overlapping with the +Y side end of the ejection channel 75A in a plan view in the first channel A row 61. The inlet common ink chamber 120 extends in the X direction by a length spanning the first channel A row 61, for example, and opens on the rear surface of the cover plate 54. The outlet common ink chamber 121 is formed at a position overlapping with the -Y side end of the ejection channel 75A in a plan view in, for example, the first channel A row 61. The inlet common ink chamber 120 extends in the X direction by a length spanning the channel A row 61 and opens on the rear surface of the cover plate 54.

[0056] In the inlet common ink chamber 120, inlet slits (first liquid flow path, second liquid flow path) 125 are formed at positions corresponding to the ejection channels 75A of the first channel A row 61. The inlet slits 125 individually communicate between the +Y side end of each ejection channel 75A and the inside of the inlet common ink chamber 120. In the outlet common ink chamber 121, outlet slits (first liquid flow path, second liquid flow path) 126 are formed at positions corresponding to the ejection channels 75A of the first channel A row 61. The outlet slits 126 individually communicate between the -Y side ends of the ejection channels 75A and the inside of the outlet common ink chamber 121. Therefore, the inlet slits 125 and the outlet slits 126 each communicate with each ejection channel 75A, but do not communicate with the non-ejection channels 76A.

[0057] In the cover plate 54, a beam portion 128 is formed between adjacent inlet common ink chambers (first common flow path, second common flow path) 120. The beam portion 128 extends linearly along the X direction. The beam portion 128 separates the adjacent inlet common ink chambers 120.

[0058] As shown in FIG. 8, a communication groove 127 is formed on the surface of the cover plate 54 (beam portion 128) at a position overlapping with the row separation groove 72 in a plan view. The communication groove 127 opens on the surface of the cover plate 54 and communicates with the inside of the row separation groove 72. The communication groove 127 extends in the X direction with a length that crosses the channel rows 61 to 64. The dimension of the communication groove 127 in the Y direction is longer than that of the row separation groove 72. Therefore, the communication groove 127 communicates with the communication portion 90 of the non-ejection channel 76 on the back surface of the actuator plate 53.

[0059] <Intermediate plate 52> The intermediate plate 52 is bonded to the surface of the actuator plate 53 so as to close each of the channel groups 66, 67. The intermediate plate 52 is formed of a piezoelectric material such as PZT, similar to the actuator plate 53. The intermediate plate 52 has a thickness in the Z direction that is thinner than the actuator plate 53. The intermediate plate 52 has a dimension in the Y direction that is shorter than the actuator plate 53. Therefore, both ends of the actuator plate 53 in the Y direction (for example, the first outer region 81) are exposed on both sides of the intermediate plate 52 in the Y direction. At both ends of the actuator plate 53 in the Y direction, the portions exposed from the intermediate plate 52 function as pressure-bonding regions for the flexible printed circuit boards 100, 101.

[0060] In the intermediate plate 52, a communication hole 130 is formed in a portion overlapping with the through-portion 75b of each discharge channel 75 in a plan view. The communication hole 130 is an A-row communication hole 130A communicating with the discharge channel 75A, and a B-row communication hole 130B communicating with the discharge channel 75B. The communication holes 130 communicate with the through-portion 75b of the corresponding discharge channel 75 on the front surface side of the actuator plate 53. The communication hole 130 is formed in an elliptical shape with the Y direction as the longitudinal direction. The dimension of the communication hole 130 in the Y direction is shorter than that of the through-portion 75b. On the other hand, the dimension of the communication hole 130 in the X direction is wider than that of the through-portion 75b. However, the dimension of the communication hole 130 in the X direction may be shorter than that of the through-portion 75b.

[0061] A first open groove 131 is formed in the intermediate plate 52 at a position overlapping with the group separating groove 71 in a plan view. The first open groove 131 opens the group separating groove 71 and exposes the second outer region 86 of the first channel B row 62 and the first outer region 81 of the second channel A row 63. The first open groove 131 is formed in a band shape extending in the X direction and having the same length as the group separating groove 71.

[0062] In the intermediate plate 52, a second open groove 132 is formed at a position overlapping with the row separation groove 72 in a plan view. The second open groove 132 opens at least the row separation groove 72. The second open groove 132 is formed in a strip shape extending in the X direction and having a length equal to that of the row separation groove 72. The length in the Y direction of the second open groove 132 may be narrower or wider than that of the row separation groove 72, as long as at least a part of the row separation groove 72 is opened through the second open groove 132. In this embodiment, the lengths in the Y direction of the second open groove 132 and the row separation groove 72 are equal to each other.

[0063] 4, the nozzle plate 51 is fixed to the surface of the intermediate plate 52 by adhesion or the like. The nozzle plate 51 has a width in the Y direction equal to that of the intermediate plate 52. In this embodiment, the nozzle plate 51 is formed of a resin material such as polyimide to a thickness of about 50 μm. However, the nozzle plate 51 may have a single layer structure or a multilayer structure made of a metal material (such as SUS or Ni-Pd), glass, silicon, or the like in addition to the resin material.

[0064] In the nozzle plate 51, four nozzle rows (a first nozzle A row 141, a first nozzle B row 142, a second nozzle A row 143, and a second nozzle B row 144) extending in the X direction are formed at intervals in the Y direction. Each nozzle row 141-144 has a plurality of nozzle holes (a first nozzle A hole 145, a first nozzle B hole 146, a second nozzle A hole 147, and a second nozzle B hole 148) penetrating the nozzle plate 51 in the Z direction. The nozzle holes 145-148 are arranged at intervals in the X direction. Each nozzle hole 145-148 is formed in a tapered shape, for example, such that the inner diameter gradually decreases from the back side to the front side. The maximum inner diameter of each nozzle hole 145-148 is equal to the width of the ejection channel 75 in the Y direction.

[0065] As shown in FIG. 6 and FIG. 9, the first nozzle A holes 145 are individually connected to the central parts of the ejection channels 75A of the first channel A row 61 in the Y direction through the A row communication holes (first communication holes) 130A. The first nozzle B holes 146 are individually connected to the central parts of the ejection channels 75B of the first channel B row 62 in the Y direction through the B row communication holes (second communication holes) 130B. The second nozzle A holes 147 are individually connected to the central parts of the ejection channels 75A of the second channel A row 63 in the Y direction through the A row communication holes 130A. The second nozzle B holes 148 are individually connected to the central parts of the ejection channels 75B of the second channel B row 64 in the Y direction through the B row communication holes 130B. Therefore, each non-ejection channel 76 does not communicate with the nozzle holes 145 to 148, and is covered by the nozzle plate 51 from the front side.

[0066] [Printer 1 operation method] Next, a case where characters, figures, etc. are recorded on a recording medium P using the printer 1 configured as described above will be described below. 1 are each fully filled with ink of a different color. Also, the ink in the ink tanks 4 is filled in the inkjet head 5 via the ink circulation mechanism 6.

[0067] When the printer 1 is operated in this initial state, the recording medium P is conveyed to the +X side while being sandwiched between the rollers 11 and 12 of the conveying mechanisms 2 and 3. At the same time, the carriage 29 moves in the Y direction, causing the inkjet head 5 mounted on the carriage 29 to move back and forth in the Y direction. While the inkjet heads 5 are moving back and forth, ink is appropriately ejected from each inkjet head 5 onto the recording medium P. In this way, characters, images, etc. can be recorded on the recording medium P.

[0068] The movement of each ink-jet head 5 will now be described in detail. In the inkjet head 5 of the circulation side chute type as in this embodiment, first, the pressurizing pump 24 and the suction pump 25 shown in FIG. 2 are operated to circulate ink in the circulation flow path 23. In this case, the ink flowing through the ink supply tube 21 is supplied into each ejection channel 75 through the inlet common ink chamber 120 and the inlet slit 125. The ink supplied into each ejection channel 75 flows through each ejection channel 75 in the Y direction. After that, the ink is discharged into the outlet common ink chamber 121 through the outlet slit 126, and then returned to the ink tank 4 through the ink discharge tube 22. In this way, ink can be circulated between the inkjet head 5 and the ink tank 4.

[0069] Then, when the inkjet head 5 starts to move back and forth by the movement of the carriage 29 (see FIG. 1), a driving voltage is applied to the electrodes 95, 97 via the flexible printed circuit boards 100, 101. At this time, the driving voltage is applied between the electrodes 95, 97 with the individual electrode 97 at driving potential Vdd and the common electrode 95 at reference potential GND. Then, thickness slip deformation occurs in the two driving walls 70 that define the ejection channel 75, and these two driving walls 70 deform so as to protrude toward the non-ejection channel 76 side. That is, by applying a voltage between the electrodes 95, 97, the driving wall 70 is bent and deformed into a V-shape around the middle part in the Z direction. This increases the volume of the ejection channel 75. Then, as the volume of the ejection channel 75 increases, the ink stored in the inlet common ink chamber 120 is guided into the ejection channel 75 through the inlet slit 125. The ink guided inside the ejection channel 75 becomes a pressure wave and propagates inside the ejection channel 75. At the timing when the pressure wave reaches the nozzle holes 145-148, the voltage applied between the electrodes 95, 97 is set to zero. This causes the driving wall 70 to return to its original state, and the volume of the ejection channel 75, which had temporarily increased, returns to its original volume. This action increases the pressure inside the ejection channel 75, and pressurizes the ink. As a result, droplets of ink are ejected to the outside through the communication hole 130 and the nozzle holes 145-148, and characters, images, and the like can be recorded on the recording medium P as described above.

[0070] <Method of Manufacturing Head Chip 50> Next, a method for manufacturing the above-mentioned head chip 50 will be described. For convenience, the following description will be given taking as an example a case in which the head chip 50 is manufactured at the chip level. FIG. 10 is an enlarged side view of plate assembly 200. The manufacturing method of the head chip 50 includes a laminating step, a protective film forming step, and a nozzle plate attaching step. Note that it is assumed that each of the plates 51 to 54 has already been subjected to necessary processing prior to the laminating step.

[0071] In the overlapping process, the actuator plate 53, the cover plate 54, and the intermediate plate 52 are bonded together with an adhesive or the like. At this time, the actuator plate 53 and the cover plate 54 are bonded together so that the discharge channels 75 of each of the channel rows 61 to 64 communicate with the corresponding slits 125 and 126. Also, the actuator plate 53 and the intermediate plate 52 are bonded together so that the discharge channels 75 of each of the channel rows 61 to 64 communicate with the corresponding communication holes 130. The actuator plate 53, the cover plate 54, and the intermediate plate 52 are bonded together to form a plate assembly 200. In this state, the discharge channels 75 communicate with the outside of the discharge channels 75 through the slits 125 and 126 and the communication holes 130. In the outer regions 81 and 86, the through portions 76a of the non-ejection channels 76 communicate with the outside of the non-ejection channels 76, and the open openings 90a communicate with the outside of the non-ejection channels 76 through the row separation grooves 72 and the second open grooves 132.

[0072] In the protective film forming process, a first protective film 110 is formed on the ejection channel 75, and a protective film 111 is formed on the inner surface of the non-ejection channel 76. The protective films 110 and 111 are formed by forming a paraxylylene resin material using, for example, chemical vapor deposition (CVD) or the like. Specifically, a raw material gas that is a material for forming the protective films 110 and 111 is introduced into the ejection channel 75 while the plate assembly 200 is set in a chamber (not shown). At this time, the raw material gas is introduced into the ejection channel 75 through the slits 125 and 126 and the communication hole 130. That is, the raw material gas is introduced from both ends of the ejection channel 75 in the Y direction through the common ink chambers 120 and 121 and the slits 125 and 126 (see arrow Q1a). The raw material gas is introduced into the center of the ejection channel 75 in the Y direction through the communication hole 130 (see arrow Q1b). The source gas introduced into the discharge channel 75 adheres to the inner surface of the discharge channel 75 , so that the first protective film 110 is deposited on the inner surface of the discharge channel 75 .

[0073] The raw material gas is introduced into the non-ejection channel 76 through the through-hole 76a and the communication part 90. That is, the raw material gas is introduced into the non-ejection channel 76 through the part (opening 53a, 53b) of the through-hole 76a that is opened in the outer regions 81, 86 (see arrow Q2a). The raw material gas enters the second open groove 132 and the row separation groove 72, and then is introduced into the non-ejection channel 76 through the opening 90a (see arrow Q2b). In addition, the raw material gas that has entered the row separation groove 72 enters the communication groove 127, and then is introduced into the non-ejection channel 76 from the back side of the actuator plate 53 through the opening 90a. The raw material gas introduced into the non-ejection channel 76 adheres to the inner surface of the non-ejection channel 76, and the second protective film 111 is deposited. In the protective film forming step, as long as the protective films 110 and 111 are formed at least on the inner surfaces of the channels 75 and , the protective film may be deposited on portions other than the inner surfaces of the channels 75 and .

[0074] Thereafter, in the nozzle plate attachment step, the nozzle plate 51 and the actuator plate 53 are attached together so that the nozzle holes 145-148 communicate with the ejection channels 75 of the corresponding channel rows 61-64 through the communication holes . In this manner, the head chip 50 is manufactured.

[0075] The head chip 50 may be manufactured at the wafer level. When manufacturing at the wafer level, first, an actuator wafer having a series of actuator plates 53, a cover wafer having a series of cover plates 54, and an intermediate wafer having a series of intermediate plates 52 are bonded together to form a wafer bonded body. After that, protective films 110 and 111 are formed on the wafer bonded body, and then the wafer bonded body is cut to form a plurality of head chips 50.

[0076] Thus, in this embodiment, in the same channel group (for example, the first channel group 66), protective films 110, 111 are formed on the inner surfaces of the ejection channels 75 and non-ejection channels 76 of the first channel A row 61, and on the inner surfaces of the ejection channels 75 and non-ejection channels 76 of the first channel B row 62, respectively. According to this configuration, the protective films 110, 111 are formed on the inner surfaces of the ejection channels 75 and the non-ejection channels 76, thereby making it possible to suppress contact between the electrodes 95, 97 formed on the inner surfaces of the ejection channels 75 and the non-ejection channels 76 and the ink. This makes it possible to suppress short-circuiting of the electrodes 95, 97 due to ink, and to maintain excellent ejection performance for a long period of time.

[0077] Particularly, in this embodiment, in the actuator plate 53, at both ends in the Y direction of the non-ejection channel 76A of the first channel A row 61, openings 53a, 90aA are formed which connect the inside and outside of the non-ejection channel 76A and allow the material for forming the second protective film 111 to be introduced into the non-ejection channel 76A. On the other hand, in the actuator plate 53, at both ends in the Y direction of the non-ejection channel 76B of the first channel B row 62, openings 53b, 90aB are formed which connect the inside and outside of the non-ejection channel 76B and allow the material for forming the second protective film 111 to be introduced into the non-ejection channel 76B. According to this configuration, the material for forming the second protective film 111 is introduced into the non-ejection channels 76 through the openings 53a, 90aA and the openings 53b, 90aB, so that the second protective film 111 can be effectively formed on the inner surfaces of the non-ejection channels 76 as well. As a result, for example, it is possible to prevent the electrodes formed on the inner surface of the non-ejection channel 76 from being short-circuited due to ink or the like that has entered the non-ejection channel 76 .

[0078] Moreover, in this embodiment, the material for forming the first protective film 110 is introduced into the discharge channel 75 through the slits 125, 126 and the communication hole 130, and the material for forming the second protective film 111 is introduced into the non-discharge channel 76 through the openings 53a, 53b, 90a. This makes it possible to effectively form the protective films 110, 111 on the inner surfaces of the discharge channel 75 and the non-discharge channel 76.

[0079] In this embodiment, the actuator plate 53 and the intermediate plate 52 are configured to have a row separation groove 72 and a second open groove 132 that connect the open opening 90aA of the non-ejection channel 76A in the first channel A row 61 to the open opening 90aB of the non-ejection channel 76B in the first channel B row 62. According to this configuration, the raw material gas for the second protective film 111 is introduced from the row separation groove 72 and the second open groove 132 through the open openings 90a into each of the non-ejection channels 76. This makes it possible to form the second protective film 111 more efficiently than in the case where the material for forming the protective film is introduced individually into each of the non-ejection channels 76 through each open opening 90a.

[0080] In this embodiment, the cover plate 54 is configured to have a communication groove 127 that communicates with the row separation groove 72 formed therein. According to this configuration, in the plate assembly 200, the pressure loss in the space leading to each opening 90a can be reduced, so that the source gas for the second protective film 111 can be efficiently introduced into the non-ejection channels 76 through each opening 90a.

[0081] In this embodiment, the width of the communication groove 127 in the X direction is wider than that of the row separation groove 72, and the communication groove 127 communicates from the rear surface side of the actuator plate 53 to the opening 90a. According to this configuration, the raw material gas for the second protective film 111 that has passed through the row separation grooves 72 and entered the communicating grooves 127 is introduced into each non-ejection channel 76 through the open openings 90a from the rear surface side of the actuator plate 53. As a result, the raw material gas for the second protective film 111 is introduced into each non-ejection channel 76 directly through the row separation grooves 72, or indirectly through the communicating grooves 127. As a result, the second protective film 111 can be efficiently formed on the inner surface of the non-ejection channel 76.

[0082] In this embodiment, the cover plate 54 is configured to have a beam portion 128 between adjacent inlet common ink chambers 120 . According to this configuration, the strength of the cover plate 54 can be easily ensured by the beam portion 128. Therefore, when bonding the actuator plate 53 and the cover plate 54 together, a bonding load can be effectively applied between the actuator plate 53 and the cover plate 54. As a result, the actuator plate 53 and the cover plate 54 can be reliably bonded to each other, and leakage of ink through the gap between the actuator plate 53 and the cover plate 54 can be suppressed. Furthermore, by forming the communicating grooves 127 in the beam portions 128, it becomes easier to ensure the depth of the communicating grooves 127. Therefore, the source gas for the second protective film 111 can be efficiently introduced into the non-ejection channels 76 through the respective openings 90a.

[0083] In this embodiment, the raised portion 76b of the first channel A row 61 crosses the row separation groove 72 in the Y direction, and the connecting portion with the row separation groove 72 forms an opening 90aA, and the raised portion 76b of the first channel B row 62 crosses the row separation groove 72 in the Y direction, and the connecting portion with the row separation groove 72 forms an opening 90aB. According to this configuration, it is easier to ensure the opening area of ​​the openings compared to a case where the row separation grooves 72 communicate with each other at the ends of the raised portions 76b. As a result, the source gas of the second protective film 111 can be efficiently introduced into the non-ejection channels 76 through the openings 90a.

[0084] The inkjet head 5 and printer 1 of the present embodiment include the head chip 50 described above, and therefore can suppress short-circuiting of electrodes caused by ink, and can maintain excellent ejection performance for a long period of time.

[0085] Second embodiment In the head chip 50 shown in FIG. 11, the communication groove 127 is provided in the center of the beam portion 128 in the Y direction. The width D1 of the communication groove 127 in the Y direction is narrower than the width D2 of the beam portion 128 in the Y direction. Therefore, the portion of the surface of the beam portion 128 located outside the communication groove 127 functions as a pressure-receiving region T1 that is joined to the actuator plate 53. The bottom surface of the inlet common ink chamber 120 is located on the back side of the top surface of the communication groove 127. Therefore, the inlet common ink chamber 120 and the communication groove 127 are arranged to be shifted in the Z direction (they do not overlap).

[0086] In this embodiment, a pressure-receiving region T1 is provided in a portion of the beam portion 128 that is positioned outside the communicating groove 127. The pressure-receiving region T1 functions as a pressure-receiving surface that receives a load acting between the actuator plate 53 and the cover plate 54 when the actuator plate 53 and the cover plate 54 are bonded together. This makes it possible to effectively apply a bonding load between the actuator plate 53 and the cover plate 54. As a result, the actuator plate and the cover plate can be bonded more reliably.

[0087] 12, the inlet common ink chamber 120 and the communication groove 127 may overlap in the Z direction. This makes it easier to ensure the depth of the communication groove 127, so that the raw material gas of the second protective film 111 can be efficiently introduced into the non-ejection channels 76 through each open port 90a.

[0088] The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. For example, in the above embodiment, the inkjet printer 1 has been described as an example of a liquid jet recording apparatus, but the liquid jet recording apparatus is not limited to a printer. For example, the liquid jet recording apparatus may be a fax machine, an on-demand printer, or the like. In the above-described embodiment, a configuration in which the inkjet head moves relative to the recording medium during printing (so-called shuttle machine) has been described as an example, but the present disclosure is not limited to this configuration. The configuration according to the present disclosure may be adopted in a configuration in which the recording medium moves relative to the inkjet head while the inkjet head is fixed (so-called fixed head machine). In the above embodiment, the recording medium P is paper, but this is not limited to the above configuration. The recording medium P is not limited to paper, and may be a metal material, a resin material, or a food product. In the above-described embodiment, the liquid ejection head is mounted on the liquid ejection recording device, but the present invention is not limited to this configuration. In other words, the liquid ejected from the liquid ejection head is not limited to the liquid that is to be landed on the recording medium, and may be, for example, a medicinal liquid to be mixed in a medicine, a food additive such as a seasoning or a fragrance to be added to food, or an aromatic to be sprayed into the air.

[0089] In the above embodiment, the configuration has been described in which the Z direction coincides with the direction of gravity, but the present invention is not limited to this configuration, and the Z direction may be aligned with the horizontal direction. In the above-described embodiment, in the first channel A row 61 and the first channel B row 62 (or the second channel A row 63 and the second channel B row 64), the non-ejection channels 76 of the first channel A row 61 and the non-ejection channels 76 of the first channel B row 62 are configured to open to a common row separation groove 72. However, the non-ejection channels 76 of the first channel A row 61 and the non-ejection channels 76 of the first channel B row 62 may each communicate with the inside and outside of the non-ejection channels 76 through separate grooves.

[0090] In the above embodiment, the cover plate 54 has a configuration in which the width of the communication groove 127 is wider than the row separation groove 72. However, the width of the communication groove 127 may be wider or narrower than the row separation groove 72. In addition, the cover plate 54 may not have the communication groove 127. In the above-described embodiment, the non-discharge channel 76 may communicate with the outside through portions other than the open ports 53a, 90a, so long as both ends of the non-discharge channel 76 communicate with the outside. In the above-described embodiment, the protective film for protecting the electrodes has been described as an example, but the protective film may be formed regardless of the presence or absence of electrodes.

[0091] In the above-described embodiment, a configuration in which the inlet common ink chamber 120 is provided for each channel row has been described, but the present invention is not limited to this configuration. For example, as shown in FIG. 13, one inlet common ink chamber 120 may be shared by adjacent channel rows 61 and 62. In this case, the inlet common ink chamber 120 is provided with an inlet slit 125 communicating with the ejection channel 75A of one channel row 61 and an inlet slit 125 communicating with the ejection channel 75B of the other channel row 62. Even in such a configuration, a communication groove 127 can be formed on the surface of the cover plate 54 at a position overlapping with the row separation groove 72 in a plan view (a portion located on the -Z side with respect to the inlet common ink chamber 120).

[0092] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate. [Explanation of symbols]

[0093] 1...Inkjet printer (liquid jet recording device) 5...Inkjet head (liquid ejection head) 50…Head tip 52...Intermediate plate (connecting plate) 53...Actuator plate 53a...Open port (first open port, first outer open port, open port) 53b...Open port (second open port, second outer open port, open port) 54…Cover plate 61...1st channel row A (1st channel area) 62...1st channel row B (2nd channel area) 63...2nd channel row A (1st channel area) 64...2nd channel row B (2nd channel area) 72...Row separation groove (common groove) 75...Discharge channel (first ejection channel, second ejection channel, ejection channel) 75A…Discharge channel (first ejection channel, ejection channel) 75B…Discharge channel (second ejection channel, ejection channel) 76...Non-ejection channel (first non-ejection channel, second non-ejection channel, non-ejection channel) 76A...Non-ejection channel (first non-ejection channel, ejection channel) 76B...Non-ejection channel (second non-ejection channel, ejection channel) 76a...Penetration part (first extension part, second extension part) 76b…Rounded section (first rounded section, second rounded section) 90a...Open port (open port, first inner open port, second inner open port) 90aA...Open port (1st open port, 1st inner open port, open port) 90aB...Open port (2nd open port, 2nd inner open port, open port) 110…First protective film (protective film) 111…Second protective film (protective film) 120... Inlet common ink chamber (first common flow path, second common flow path) 125...Inlet slit (first liquid flow path, second liquid flow path, liquid flow path) 126...Outlet slit (first liquid flow path, second liquid flow path, liquid flow path) 127...Communication groove 128...beam part 130A…Communication hole (1st communication hole, communication hole) 130B...Communication hole (second communication hole, communication hole)

Claims

1. an actuator plate in which a first channel region in which first ejection channels and first non-ejection channels extending in a first direction are arranged in a second direction intersecting the first direction, and a second channel region in which second ejection channels and second non-ejection channels extending in the first direction are arranged in the second direction are provided side by side in the first direction; a cover plate overlaid on the actuator plate, the cover plate having a first liquid flow path communicating with the first ejection channel and a second liquid flow path communicating with the second ejection channel, and a communication plate overlaid on a side of the actuator plate opposite to the cover plate, the communication plate having a first communication hole communicating with the first ejection channel at a center in the first direction and a second communication hole communicating with the second ejection channel at a center in the first direction, a protective film is formed on an inner surface of the first ejection channel, an inner surface of the first non-ejection channel, an inner surface of the second ejection channel, and an inner surface of the second non-ejection channel; In the actuator plate, first openings are formed at both ends of the first non-ejection channel in the first direction, the first openings communicating the inside and the outside of the first non-ejection channel, A head chip, in which second openings are formed at both ends of the second non-ejection channel in the first direction in the actuator plate, for connecting the inside and outside of the second non-ejection channel.

2. The first opening is a first inner opening located at an end of the first non-ejection channel on the second channel region side in the first direction; a first outer opening located at an end of the first non-ejection channel opposite to the second channel region in the first direction, The second opening is a second inner opening located at an end of the second non-ejection channel on the first channel region side in the first direction; a second outer opening located at an end of the second non-ejection channel opposite to the first channel region in the first direction, The head chip described in claim 1, wherein a common groove extending in the second direction is formed in the boundary portion of the actuator plate and the communicating plate located between the first channel region and the second channel region in the first direction, connecting the first inner openings of the first non-ejection channels and the second inner openings of the second non-ejection channels.

3. The head chip according to claim 2 , wherein the cover plate has a communicating groove formed therein, the communicating groove communicating with the common groove.

4. The width of the communication groove in the first direction is wider than that of the common groove, The head chip according to claim 3 , wherein the communication groove communicates with the first inner opening and the second inner opening from an opposite side of the actuator plate to the communication plate.

5. The cover plate is a first common flow path collectively communicating with the plurality of first liquid flow paths; a second common flow path that is collectively connected to the second liquid flow paths, A head chip as described in claim 3 or claim 4, wherein a portion of the cover plate located between the first liquid flow path and the second common flow path separates the first common flow path and the second common flow path and forms a beam portion extending in the second direction.

6. The communication groove is formed in the beam portion, The head chip according to claim 5 , wherein the width of the communicating groove in the first direction is narrower than the width of the beam portion in the first direction.

7. The head chip according to claim 6 , wherein the communication groove, the first common flow path and the second common flow path overlap in a direction in which the actuator plate and the cover plate are overlapped.

8. The first non-ejection channel includes: A first extension portion extending in the first direction; a first raised portion having a groove depth that gradually decreases from the first extension portion toward the second channel region in the first direction, The second non-ejection channel includes: A second extension portion extending in the first direction; a second raised portion having a groove depth that gradually decreases from the second extension portion toward the first channel region in the first direction, the first raised portion crosses the common groove in the first direction, and a communicating portion with the common groove constitutes the first inner opening, The head chip according to claim 2 , wherein the second cut-out portion crosses the common groove in the first direction, and a portion communicating with the common groove forms the second inner opening.

9. A liquid-jet head comprising the head chip according to claim 1 .

10. A liquid jet recording apparatus comprising the liquid jet head according to claim 9.

11. an actuator plate having ejection channels and non-ejection channels extending in a first direction and arranged in a second direction intersecting the first direction; a cover plate having a liquid flow passage communicating with the ejection channel and overlaid on the actuator plate; a communication plate having a communication hole communicating with the ejection channel at a center portion in the first direction and overlapping the actuator plate on an opposite side to the cover plate, the method comprising: In the actuator plate, openings are formed at both ends of the non-ejection channel in the first direction to allow communication between the inside and the outside of the non-ejection channel, a protective film forming step of forming a protective film on an inner surface of the ejection channel and an inner surface of the non-ejection channel; The protective film forming process is a method for manufacturing a head chip, in which a material for forming the protective film is introduced into the ejection channel through the liquid flow path and the communicating hole, and the material for forming the protective film is introduced into the non-ejection channel through the opening.

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