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

Abstract

Provided are a head chip, a liquid ejection head, a liquid ejection recording apparatus, and a method for manufacturing a head chip that can suppress short-circuiting of electrodes caused by ink and maintain excellent ejection performance over a long period. A head chip (50) according to one aspect of the present disclosure includes an actuator plate (53), a cover plate (54), and an intermediate plate (52). In the actuator plate (53), openings (53a, 90Aa) that communicate the inside and outside of the non-ejection channel (76A) are formed at both end portions in the Y direction in the non-ejection channel (76A). In the actuator plate (53), openings (53b, 90aB) that communicate the inside and outside of the non-ejection channel (76B) are formed at both end portions in the Y direction in the non-ejection channel (76B).

Description

Technical Field

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

[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 the non-ejection channels, respectively.

[0003] In the head chip, a voltage applied to the electrodes causes a volume change in the ejection channels, so that the ink in the ejection channels is ejected through nozzle holes formed in the nozzle plate.

[0004] For example, in Patent Documents 1 and 2 described below, a configuration is disclosed in which an insulating protective film covering the electrodes is formed on the inner surface of the ejection channels. It is also considered that, according to this configuration, even when conductive ink is used, it is possible to suppress short-circuiting of the electrodes in the ejection channels via the ink.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-131175;

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2017-136724. Summary of the Invention

[0009] Problems to be Solved by the Invention

[0010] However, in the head chip, there is a possibility that conductive ink flows from the inside of the ejection channels into the non-ejection channels through gaps in the actuator plate or joining portions between the actuator plate and other components.

[0011] However, in the existing configuration, there is still room for improvement in actively forming a protective film on the inner surface area of the non-ejection channels. In the case where it is assumed that ink flows into the non-ejection channels, there is a possibility that the electrodes formed on the inner surface of the non-ejection channels are short-circuited via the ink.

[0012] The present disclosure provides a head chip, a liquid ejection head, a liquid ejection recording apparatus, and a method for manufacturing a head chip that can suppress short-circuiting of electrodes caused by ink and maintain excellent ejection performance over a long period.

[0013] Means for Solving the Problems

[0014] To solve the above problems, the present disclosure adopts the following mode.

[0015] (1) The head chip according to one aspect of the present disclosure includes: an actuator plate having a first channel region in which a first ejection channel and a first non-ejection channel extending in the first direction are arranged side by side in the first direction and arranged in a second direction intersecting the first direction, and a second channel region in which a second ejection channel and a second non-ejection channel extending in the first direction are arranged in the second direction; a 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 overlapping with the actuator plate; and a communication plate having a first communication hole communicating with the first ejection channel at the central portion in the first direction and a second communication hole communicating with the second ejection channel at the central portion in the first direction, overlapping with the actuator plate on the side opposite to the cover plate. Protective films are respectively formed on the inner surfaces of the first ejection channel, the first non-ejection channel, the second ejection channel, and the second non-ejection channel. In the actuator plate, first openings that communicate the inside and outside of the first non-ejection channel are formed at both ends in the first direction of the first non-ejection channel, and second openings that communicate the inside and outside of the second non-ejection channel are formed at both ends in the first direction of the second non-ejection channel.

[0016] According to this aspect, by introducing the formation material of the protective film into the first non-ejection channel through the first openings formed at both ends of the first non-ejection channel, the protective film can be effectively formed on the inner surface of the first non-ejection channel. By introducing the formation material of the protective film into the second non-ejection channel through the second openings formed at both ends of the second non-ejection channel, the protective film can be effectively formed on the inner surface of the second non-ejection channel.

[0017] As a result, it is possible to suppress, for example, an electrode short circuit or the like formed on the inner surface of the non-ejection channel due to liquid or the like entering the non-ejection channel.

[0018] (2) In the head chip of the above (1) style, preferably, the first opening includes a first inner opening at the end on the second channel region side in the first direction in the first non-injection channel and a first outer opening at the end on the side opposite to the second channel region side in the first direction in the first non-injection channel, the second opening includes a second inner opening at the end on the first channel region side in the first direction in the second non-injection channel and a second outer opening at the end on the side opposite to the first channel region side in the first direction in the second non-injection channel, and a common groove is formed at the boundary portion between the first channel region and the second channel region in the first direction in the actuator plate and the communication plate, which connects the first inner openings in the plurality of first non-injection channels and the second inner openings in the plurality of second non-injection channels and extends in the second direction.

[0019] According to this style, the forming material of the protective film is introduced into each non-injection channel from the common groove through each inner opening. Thus, compared with the case where the forming material of the protective film is separately introduced into each non-injection channel through each inner opening, the protective film can be formed efficiently.

[0020] (3) In the head chip of the above (2) style, preferably, a communication groove communicating with the common groove is formed in the cover plate.

[0021] According to this style, the pressure loss in the space reaching each opening can be reduced, and thus the forming material of the protective film can be efficiently introduced into the non-injection channel through each inner opening.

[0022] (4) In the head chip of the above (3) style, preferably, the width of the communication groove in the first direction is wider than that of the common groove, and the communication groove communicates with the first inner opening and the second inner opening from the side opposite to the communication plate with respect to the actuator plate.

[0023] According to this style, the forming material of the protective film entering the communication groove through the common groove is introduced into each non-injection channel from the side opposite to the communication plate with respect to the actuator plate through each inner opening. Thus, the forming material of the protective film is introduced into each non-injection channel directly through the common groove or indirectly through the communication groove. As a result, the protective film can be efficiently formed on the inner surface of the non-injection channel.

[0024] (5) In the head chip of the type described in (3) or (4) above, preferably, the cover plate has a first common flow path communicating with a plurality of the first liquid flow paths and a second common flow path communicating with a plurality of the second liquid flow paths. A portion of the cover plate located between the first liquid flow path and the second common flow path forms a beam portion that separates between the first common flow path and the second common flow path and extends in the second direction.

[0025] According to this aspect, it becomes easy to ensure the strength of the cover plate through the beam portion. Therefore, when bonding the actuator plate to 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 joined, and leakage of ink between the actuator plate and the cover plate can be suppressed.

[0026] (6) In the head chip of the type described in (5) above, preferably, the communication groove is formed in the beam portion, and the width of the communication groove in the first direction is narrower than the width of the beam portion in the first direction.

[0027] According to this aspect, by forming the communication groove in the beam portion, it becomes easy to ensure the depth of the communication groove. Therefore, the raw material gas of the protective film can be efficiently introduced into the non-injection channel through each opening.

[0028] Further, since the width of the communication groove in the first direction is narrower than the width of the beam portion in the first direction, a portion of the beam portion located outside the communication groove forms a pressure-bearing area. The pressure-bearing area functions as a pressure-bearing surface that bears the load acting between the actuator plate and the cover plate when bonding the actuator plate to the cover plate. Thereby, a bonding load can be effectively applied between the actuator plate and the cover plate. As a result, leakage of ink between the actuator plate and the cover plate can be suppressed.

[0029] (7) In the head chip of the type described in (6) above, preferably, the communication groove coincides with the first common flow path and the second common flow path in the coincidence direction in which the actuator plate and the cover plate coincide.

[0030] According to this aspect, it becomes easy to ensure the depth of the communication groove, and therefore, the raw material gas of the protective film can be efficiently introduced into the non-injection channel through each opening.

[0031] (8) In the head chip of any one of the patterns (2) to (7) above, preferably, the first non-injection channel includes a first extension portion extending along the first direction and a first upper cut portion whose groove depth gradually becomes shallower as it moves from the first extension portion toward the second channel region side in the first direction. The second non-injection channel includes a second extension portion extending along the first direction and a second upper cut portion whose groove depth gradually becomes shallower as it moves from the second extension portion toward the first channel region side in the first direction. The first upper cut portion traverses the common groove in the first direction, and the communication portion with the common groove constitutes the first inner opening. The second upper cut portion traverses the common groove in the first direction, and the communication portion with the common groove constitutes the second inner opening.

[0032] According to this pattern, compared with the case where the common groove communicates at the end of the upper cut portion, it is easier to ensure the opening area of the inner opening. Thus, the forming material of the protective film can be efficiently introduced into the non-injection channel through each inner opening.

[0033] (9) The liquid ejection head according to this pattern includes the head chip according to any one of the patterns (1) to (7) above.

[0034] According to this pattern, since it includes the head chip according to any one of the above patterns, it is possible to suppress short circuits of electrodes caused by liquid and maintain excellent ejection performance in the long term.

[0035] (10) The liquid ejection recording apparatus according to this pattern includes the liquid ejection head according to the pattern (9) above.

[0036] According to this pattern, since it includes the liquid ejection head according to the above pattern, it is possible to suppress short circuits of electrodes caused by liquid and maintain excellent ejection performance in the long term.

[0037] (11) The manufacturing method of the head chip according to one aspect of the present disclosure is a manufacturing method of the head chip in which the forming material of the protective film is introduced into the non-jetting channel through the aforementioned opening, and is a manufacturing method of the head chip having the following: an actuator plate in which jetting channels and non-jetting channels extending in the aforementioned first direction are arranged in a second direction intersecting the first direction; a cover plate having a liquid flow path communicating with the aforementioned jetting channels and overlapping with the aforementioned actuator plate; and a connection plate having connection holes communicating with the aforementioned jetting channels at the central portion in the aforementioned first direction, overlapping with the aforementioned actuator plate on the side opposite to the aforementioned cover plate. In the aforementioned actuator plate, at both ends in the aforementioned first direction in the aforementioned non-jetting channel, openings are formed to communicate the inside and outside of the aforementioned non-jetting channel, and there is a protective film forming step of forming a protective film on the inner surface of the aforementioned jetting channel and the inner surface of the aforementioned non-jetting channel. In the aforementioned protective film forming step, the forming material of the protective film is introduced into the aforementioned jetting channel through the aforementioned liquid flow path and the aforementioned connection holes, and the forming material of the protective film is introduced into the aforementioned non-jetting channel through the aforementioned opening.

[0038] According to this aspect, by introducing the forming material of the protective film into the jetting channel through the liquid flow path and the connection holes, and introducing the forming material of the protective film into the non-jetting channel through the opening, it is possible to effectively form a protective film on the inner surface of the jetting channel and the inner surface of the non-jetting channel.

[0039] As a result, it is possible to suppress a short circuit of an electrode formed on the inner surface of the jetting channel or the non-jetting channel due to, for example, liquid entering the jetting channel or the non-jetting channel.

[0040] Effects of the Invention

[0041] According to one aspect of the present disclosure, it is possible to suppress a short circuit of an electrode caused by liquid and maintain excellent jetting performance in the long term. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic configuration diagram of an inkjet printer according to the first embodiment.

[0043] Figure 2 It is a schematic configuration diagram of an inkjet head and an ink circulation mechanism according to the first embodiment.

[0044] Figure 3 It is a perspective view of a head chip in a state where a nozzle plate according to the first embodiment has been removed, viewed from the -Z side.

[0045] Figure 4 It is an exploded perspective view of a head chip according to the first embodiment.

[0046] Figure 5It is a bottom view of the actuator plate according to the first embodiment.

[0047] Figure 6 It corresponds to Figure 5 The sectional view taken along line VI-VI.

[0048] Figure 7 It corresponds to Figure 5 The sectional view taken along line VII-VII.

[0049] Figure 8 It is Figure 7 The enlarged view of part VIII.

[0050] Figure 9 It is along Figure 4 The sectional view taken along line IX-IX.

[0051] Figure 10 It is an enlarged sectional view of the plate assembly according to the first embodiment.

[0052] Figure 11 It is an enlarged sectional view of the head chip according to the second embodiment.

[0053] Figure 12 It is an enlarged sectional view of the head chip according to another configuration of the second embodiment.

[0054] Figure 13 It is an enlarged sectional view of the head chip according to the modified example. Detailed implementation manners

[0055] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the embodiments or modified examples described below, corresponding components may be denoted by the same reference numerals and description thereof may be omitted. In addition, in the following description, expressions indicating relative or absolute configurations such as "parallel" or "orthogonal", "center", "coaxial", etc. represent not only the strictly configured states but also the states of relative displacement with tolerances or angles and distances that can achieve the same functions. In the following embodiments, an inkjet printer (hereinafter, simply referred to as a printer) that records on a recording medium using ink (liquid) will be exemplified. In addition, in the drawings used in the following description, the scales of the respective components are appropriately changed so as to be able to recognize the sizes of the components.

[0056] (First embodiment)

[0057] [Printer 1]

[0058] Figure 1 It is a schematic configuration diagram of printer 1.

[0059] As Figure 1As shown, the printer (liquid jet recording apparatus) 1 of the present embodiment includes a pair of transport mechanisms 2 and 3 , an ink tank 4 , an inkjet head (liquid jet head) 5 , an ink circulation mechanism 6 , and a scanning mechanism 7 .

[0060] In the following description, the orthogonal coordinate system of X, Y, and Z is used for description as needed. In this case, the X direction (second direction) is consistent with the conveying direction (sub-scanning direction) of the recording medium P (such as paper, etc.). The Y direction (first direction) is consistent with the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction shows the height direction (gravity direction) that is orthogonal to the X direction and the Y direction. In the following description, the X direction, the Y direction, and the Z direction are described with the arrow side in the figure as the positive (+) side and the side opposite to the arrow as the negative (-) side. In this embodiment, the +Z side is equivalent to the upper side in the gravity direction, and the -Z side is equivalent to the lower side in the gravity direction.

[0061] 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.

[0062] The ink tanks 4 contain, for example, four colors of ink, yellow, magenta, cyan, and black, respectively. Each inkjet head 5 is configured to eject four colors of ink, yellow, magenta, cyan, and black, respectively, corresponding to the connected ink tanks 4. Ink contained in the ink tanks 4 may be conductive ink or non-conductive ink.

[0063] Figure 2 It is a schematic diagram of the structure of the inkjet head 5 and the ink circulation mechanism 6.

[0064] like Figure 1 , Figure 2 As shown, the ink circulation mechanism 6 circulates the 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.

[0065] The pressure pump 24 pressurizes the inside of the ink supply tube 21, and delivers the ink to the inkjet head 5 through the ink supply tube 21. Thus, the ink supply tube 21 side has a positive pressure relative to the inkjet head 5.

[0066] The suction pump 25 depressurizes the ink discharge tube 22, and sucks ink from the inkjet head 5 through the ink discharge tube 22. As a result, the ink discharge tube 22 side becomes negative pressure relative to the inkjet head 5. The ink can circulate between the inkjet head 5 and the ink tank 4 through the circulation flow path 23 by driving the pressure pump 24 and the suction pump 25.

[0067] The scanning mechanism 7 reciprocally scans the inkjet head 5 in the Y direction. The scanning mechanism 7 includes a guide rail 28 extending in the Y direction and a carriage 29 movably supported by the guide rail 28.

[0068] <inkjet head 5>

[0069] As Figure 1 shown, the inkjet head 5 is mounted on the 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 Figure 3 ), an ink supply section (not shown) connecting the ink circulation mechanism 6 and the head chip 50, and a control section (not shown) applying a drive voltage to the head chip 50.

[0070] <head chip 50>

[0071] Figure 3 is a perspective view of the head chip 50 in a state where the nozzle plate 51 has been removed, as viewed from the -Z side. Figure 4 is an exploded perspective view of the head chip 50.

[0072] Figure 3 , Figure 4 As shown in Figure 4 , the head chip 50 shown is a so-called circulation type side ejection type head chip 50 that circulates ink between the ink tank 4 and ejects ink from the central portion in the extending direction (Y direction) of the ejection channel 75 described later. The head chip 50 includes a nozzle plate 51 (see Figure 4 ), an intermediate plate (communication plate) 52, an actuator plate 53, and a cover plate 54. The head chip 50 has a structure in which the nozzle plate 51, the intermediate plate 52, the actuator plate 53, and the cover plate 54 are laminated in this order in the Z direction. In the following description, in the Z direction, the direction from the nozzle plate 51 toward the cover plate 54 (+Z side) 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.

[0073] The actuator plate 53 is formed of a piezoelectric material such as PZT (lead zirconate titanate). The actuator plate 53 is, for example, a so-called V-shaped substrate formed by laminating two piezoelectric plates having different polarization directions in the Z direction. However, the actuator plate 53 may also be a so-called unipolar substrate having a unidirectional polarization direction over the entire region in the Z direction.

[0074] Figure 5 is a bottom view of the actuator plate 53.

[0075] As Figure 4 , Figure 5As shown, in the actuator plate 53, a plurality of (e.g., four columns) channel columns 61-64 are formed. Each of the channel columns 61-64 extends in the X direction and is arranged at intervals in the Y direction. In the present embodiment, the channel columns 61-64 are the first channel A column (first channel region) 61, the first channel B column (second channel region) 62, the second channel A column (first channel region) 63, and the second channel B column (second channel region) 64. The first channel A column 61 and the first channel B column 62 constitute the first channel group 66. The second channel A column 63 and the second channel B column 64 constitute the second channel group 67.

[0076] As Figure 5 shown, in the actuator plate 53, in a portion located between the respective channel groups 66, 67, a group separation groove 71 is formed. 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 between the respective channel groups 66, 67. In addition, the head chip 50 has the same configuration on both sides in the Y direction with respect to the group separation groove 71. Therefore, in the following description, the configuration on the -Y side with respect to the group separation groove 71 will be mainly described, and the description of the +Y side configuration will be appropriately omitted.

[0077] In the actuator plate 53, in a portion located between the first channel A column 61 and the first channel B column 62, and in a portion located between the second channel A column 63 and the second channel B column 64, column separation grooves 72 are respectively formed. The column separation grooves 72 penetrate the actuator plate 53 in the Z direction and extend in the X direction. The width of the column separation grooves 72 in the Y direction is narrower than that of the group separation groove 71. In addition, the respective separation grooves 71, 72 do not penetrate the actuator plate 53 in the X direction.

[0078] Hereinafter, for the configuration of the channel columns 61-64, the first channel A column 61 will be taken as an example for description. In the following description, for the configuration related to the A column in each of the channel columns 61-64, an A is appended to the end of the symbol, and for the configuration related to the B column, a B is appended to the end of the symbol. Sometimes, the description of the same or corresponding configurations in the A column and the B column is omitted. In addition, in each of the channel columns 61-64, when it is not necessary to distinguish between the A column and the B column, the A or B at the end of the symbol is omitted.

[0079] The first-channel A columns 61 are formed on the side (-Y side) of the actuator plate 53 opposite to the group separation groove 71 with respect to the column separation groove 72. The first-channel A columns 61 have ejection channels (first ejection channels) 75A filled with ink and non-ejection channels (first non-ejection channels) 76A not filled with ink. Each of the channels 75A and 76A extends linearly in the Y direction in a plan view observed from the Z direction, and they are alternately arranged side by side at intervals in the X direction. The portion of the actuator plate 53 located between the ejection channel 75A and the non-ejection channel 76A constitutes a drive wall 70 that separates the ejection channel 75A and the non-ejection channel 76A in the X direction (see Figure 4 ). In addition, in the present embodiment, a configuration in which the channel extension direction coincides with the Y direction is described, but the channel extension direction may also intersect the Y direction.

[0080] Figure 6 is equivalent to Figure 5 is a cross-sectional view taken along line VI-VI.

[0081] As Figure 6 shown, the ejection channel 75A is formed in a curved shape that bulges toward the surface side in a side view observed from the X direction. The ejection channel 75, for example, is formed by inserting a disk-shaped cutter from the back side (+Z side) of the actuator plate 53. Specifically, the ejection channel 75A has upper cut portions 75a located at both ends in the Y direction and a through portion 75b located between the respective upper cut portions 75a.

[0082] The upper cut portion 75a is, for example, an arc-shaped one with a curvature radius that extends following the curvature radius of the cutter when observed from the X direction. The upper cut portion 75a bends toward the back side and extends while moving away from the through portion 75b in the Y direction.

[0083] The through portion 75b penetrates the actuator plate 53 in the Z direction.

[0084] Figure 7 is equivalent to Figure 5 is a cross-sectional view taken along line VII-VII.

[0085] As Figure 7 shown, the non-ejection channel 76A is adjacent to the ejection channel 75A in the X direction with the drive wall 70 interposed therebetween. The non-ejection channel 76A is formed, for example, by inserting a disk-shaped cutter from the back side (+Z side) of the actuator plate 53. The non-ejection channel 76A includes a through portion (first extension portion) 76a and an upper cut portion (first upper cut portion) 76b.

[0086] The through portion 76a penetrates the actuator plate 53 in the Z direction. That is, with respect to the through portion 76a, the groove depth in the Z direction is formed to be the same. The through portion 76a constitutes the portion of the non-ejection channel 76 except for the +Y side end portion.

[0087] The upper cut portion 76b forms the +Y side end portion in the non-ejection channel 76. The upper cut portion 76b is, for example, in the shape of an arc with a radius of curvature that extends following the radius of curvature of a dicing machine when viewed in the X direction. The upper cut portion 76b bends toward the back side and extends while moving away from the through portion 76a in the Y direction.

[0088] As Figure 6 , Figure 7 shown, the dimension of the non-ejection channel 76A in the Y direction is longer than that of the ejection channel 75A. Specifically, the -Y side end portion of the through portion 76a in the non-ejection channel 76A is located on the -Y side more than the ejection channel 75A, and the +Y side end portion of the upper cut portion 76b is located on the +Y side more than the ejection channel 75A.

[0089] As Figure 5 shown, the first channel B column 62 is provided between the group separation groove 71 and the column separation groove 72 in the actuator plate 53. The first channel B column 62 is configured as follows: Similar to the above-described first channel A column 61, the ejection channels (second ejection channels) 75B and the non-ejection channels (second non-ejection channels) 76B are alternately arranged side by side in the X direction. Specifically, the ejection channels 75B and the non-ejection channels 76B are arranged with a pitch deviation of a half pitch from the arrangement pitch of the ejection channel 75A and the non-ejection channel 76A. Therefore, in the inkjet head 5 of the present embodiment, the ejection channels 75 of the first channel A column 61 and the first channel B column 62 and the non-ejection channels 76 of the first channel A column 61 and the first channel B column 62 are arranged in a staggered manner (different from each other). That is, between the adjacent channel columns 61, 62, the ejection channels 75 and the non-ejection channels 76 face each other in the Y direction. However, between the respective channel columns 61, 62, the ejection channels 75 and the non-ejection channels 76 may also face each other in the Y direction. In addition, the respective channel columns 61 - 64 may be arranged with a pitch deviation of 1 / 4 pitch from the arrangement pitch of the ejection channel 75A and the non-ejection channel 76A of the first channel A column 61, respectively.

[0090] In each of the channel columns 61, 62, the ejection channels 75 are formed symmetrically with respect to the XZ plane passing through the center in the Y direction in the column separation groove 72.

[0091] In each of the channel columns 61, 62, the non-ejection channels 76 are formed symmetrically with respect to the XZ plane passing through the center in the Y direction in the column separation groove 72.

[0092] The portion of the ejection channel 75A (penetration portion 75b) in the actuator plate 53 that is located on the -Y side with respect to the A column 61 of the first channel constitutes the first outer region 81. The portion between the portion of the ejection channel 75A in the actuator plate 53 that is located on the +Y side with respect to the A column 61 of the first channel and the column separation groove 72 constitutes the first inner region 82.

[0093] The portion between the portion of the ejection channel 75B in the actuator plate 53 that is located on the -Y side with respect to the B column 62 of the first channel and the column separation groove 72 constitutes the second inner region 85. The portion between the portion of the ejection channel 75B in the actuator plate 53 that is located on the +Y side with respect to the B column 62 of the first channel and the group separation groove 71 constitutes the second outer region 86.

[0094] As Figure 7 shown, in the A column 61 of the first channel, the penetration portion 76a of the non-ejection channel 76A penetrates the first outer region 81 in the Y direction and the Z direction. The opening portion on the outer surface of the first outer region 81 in the penetration portion 76a constitutes an opening (first outer opening) 53a that allows the non-ejection channel 76A to communicate inside and outside.

[0095] Figure 8 is Figure 7 an enlarged view of part VIII.

[0096] As Figure 8 shown, in the A column 61 of the first channel, the upper cut portion 76b of the non-ejection channel 76A traverses the column separation groove 72 in the Y direction. Therefore, a part (the +Y side end portion) of the upper cut portion 76b reaches the second inner region 85 of the B column 62 of the first channel. Specifically, the portion of the upper cut portion 76b of the non-ejection channel 76A that is located in the first inner region 82 constitutes a communication portion 90A that allows the penetration portion 76a to communicate with the column separation groove 72. The communication portion 90A opens in the column separation groove 72 through an opening (first inner opening) 90aA. The portion of the upper cut portion 76b of the non-ejection channel 76A that reaches the second inner region 85 constitutes a separated portion 91A separated by the column separation groove 72.

[0097] As Figure 6 shown, in the B column 62 of the first channel, the penetration portion 76a of the non-ejection channel 76B penetrates the second outer region 86 in the Y direction and the Z direction. The opening portion on the outer surface of the second outer region 86 in the penetration portion 76a constitutes an opening (second outer opening) 53b that allows the non-ejection channel 76B to communicate inside and outside.

[0098] As Figure 8As shown, in the first channel B column 62, the upper cut portion (second upper cut portion) 76b of the non-jetting channel 76B traverses the column separation groove 72 in the Y direction. Accordingly, a part (-Y side end portion) of the upper cut portion 76b reaches the first inner region 82 of the first channel A column 61. Specifically, the part of the upper cut portion 76b that is located in the second inner region 85 and constitutes the first channel B column 62 forms a communication portion 90B that connects the through portion (second extended portion) 76a to the column separation groove 72. The communication portion 90B opens into the column separation groove 72 through the opening 90aB. The part of the upper cut portion 76b of the non-jetting channel 76B that reaches the first inner region 82 forms a separated portion 91B separated by the column separation groove 72. In addition, as long as the upper cut portion 76b is configured to be at least connected within the column separation groove 72, it may not traverse the column separation groove 72. That is, the upper cut portion 76b may also be configured without the separated portion 91.

[0099] Figure 9 is a sectional view taken along the Figure 4 IX-IX line.

[0100] As Figure 9 shown, on the inner side surface (the surfaces of the jetting channels 75 that face each other in the X direction) of the driving wall 70 of the actuator plate 53 facing each jetting channel 75, common electrodes 95 are respectively formed. The common electrodes 95 are formed over the entire region in the Z direction on the inner side surface of the jetting channels 75. The length of the common electrodes 95 in the Y direction is equal to that of the through portion 75b of the jetting channels 75 (equal to the opening length of the jetting channels 75 at the surface of the actuator plate 53).

[0101] As Figure 5 shown, on the surface of the actuator plate 53, a plurality of common terminals 96 are formed. The common terminals 96 are in the form of strips extending parallel to each other in the Y direction. Each common terminal 96 is connected to a pair of common electrodes 95 at the opening edge of the corresponding jetting channel 75. Each common terminal 96 terminates within the corresponding outer regions 81, 86.

[0102] As Figure 9 shown, on the inner side surface (the surfaces of the non-jetting channels 76 that face each other in the X direction) of the driving wall 70 of the actuator plate 53 facing each non-jetting channel 76, individual electrodes 97 are formed. The individual electrodes 97 are formed over the entire region in the Z direction on the inner side surface of the non-jetting channels 76.

[0103] As Figure 5As shown, on the surfaces of the outer regions 81 and 86, in portions located outside the common terminal 96 in the Y direction, individual terminals 98 are formed. The individual terminals 98 are strip-shaped extending in the X direction. The individual terminals 98 connect the individual electrodes 97 that sandwich the ejection channel 75 and are opposed to each other in the X direction at the opening edges of the non-ejection channels 76 that sandwich the ejection channel 75. Further, in the outer regions 81 and 86, in portions located between the common terminal 96 and the individual terminals 98, division grooves 99 are formed. The division grooves 99 extend in the X direction in each of the outer regions 81 and 86. The division grooves 99 separate the common terminal 96 and the individual terminals 98. Further, for Figure 3 , Figure 4 , etc., only a part of each of the electrodes 95, 97 and each of the terminals 96, 98 is shown.

[0104] As Figure 6 shown, on the surface of the first outer region 81, a first flexible printed circuit board 100 is press-fitted. The first flexible printed circuit board 100 is connected to the common terminal 96 and the individual terminals 98 corresponding to the first channel A column 61 on the surface of the first outer region 81. The first flexible printed circuit board 100 is pulled out toward the +Z side through the outside of the actuator plate 53.

[0105] On the surface of the second outer region 86, a second flexible printed circuit board 101 is press-fitted. The second flexible printed circuit board 101 is connected to the common terminal 96 and the individual terminals 98 corresponding to the first channel B column 62 on the surface of the second outer region 86. The second flexible printed circuit board 101 is pulled out toward the +Z side through the group separation groove 71.

[0106] As Figure 9 shown, on the inner surface of the ejection channel 75, a first protective film 110 is formed. 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 inhibits, for example, the contact between the common electrode 95 and the ink. Further, the first protective film 110 only needs to cover the common electrode 95 on the inner side surface of the ejection channel 75.

[0107] On the inner surface of the non-ejection channel 76, a second protective film 111 is formed. 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 electrode 97. The second protective film 111 inhibits, for example, the contact between the individual electrode 97 and the ink, etc. Further, the second protective film 111 only needs to cover the individual electrode 97 on the inner side surface of the non-ejection channel 76.

[0108] The protective films 110 and 111 include organic insulating materials such as p-xylene-based resin materials (e.g., PARALINE (registered trademark)). The protective films 110 and 111 may also be made of tantalum oxide (Ta2O5), silicon nitride (SiN), silicon carbide (SiC), silicon dioxide (SiO2), diamond-like carbon, or the like, or may include at least any one of these.

[0109] <Cover plate 54>

[0110] As Figure 3 、 Figure 4 shown, the cover plate 54 is bonded to the back surface of the actuator plate 53 to block the respective channel groups 66 and 67. In the cover plate 54, an inlet common ink chamber 120 and an outlet common ink chamber 121 are respectively formed at positions corresponding to the respective channel columns 61 - 64.

[0111] The inlet common ink chamber 120 is formed, for example, at a position that overlaps with the +Y side end portion of the ejection channel 75A in a plan view in the first channel A column 61. The inlet common ink chamber 120 extends, for example, along the X direction across the length of the first channel A column 61 and opens on the back surface of the cover plate 54.

[0112] The outlet common ink chamber 121 is formed, for example, at a position that overlaps with the -Y side end portion of the ejection channel 75A in a plan view in the first channel A column 61. The outlet common ink chamber 121 extends along the X direction across the length of the channel A column 61 and opens on the back surface of the cover plate 54.

[0113] In the inlet common ink chamber 120, an inlet slit (first liquid flow path, second liquid flow path) 125 is formed at a position corresponding to the ejection channel 75A in the first channel A column 61. The inlet slit 125 individually communicates between the +Y side end portions of the respective ejection channels 75A and the inside of the inlet common ink chamber 120.

[0114] In the outlet common ink chamber 121, an outlet slit (first liquid flow path, second liquid flow path) 126 is formed at a position corresponding to the ejection channel 75A in the first channel A column 61. The outlet slit 126 individually communicates between the -Y side end portions of the respective ejection channels 75A and the inside of the outlet common ink chamber 121. Therefore, the inlet slit 125 and the outlet slit 126 respectively communicate with the respective ejection channels 75A, and on the other hand, do not communicate with the non-ejection channels 76A.

[0115] 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 between adjacent inlet common ink chambers 120.

[0116] As Figure 8 shown, on the surface of the cover plate 54 (beam portion 128), at a position overlapping with the column separation groove 72 in a plan view, a communication groove 127 is formed. The communication groove 127 opens on the surface of the cover plate 54 and communicates within the column separation groove 72. The communication groove 127 extends in the X direction along the length crossing the channel columns 61 - 64. The dimension of the communication groove 127 in the Y direction is longer than that of the column 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.

[0117] <Intermediate plate 52>

[0118] The intermediate plate 52 is bonded to the surface of the actuator plate 53 so as to block each channel group 66, 67. The intermediate plate 52 is formed of a piezoelectric material such as PZT, similarly to the actuator plate 53. The thickness of the intermediate plate 52 in the Z direction is thinner than that of the actuator plate 53. The dimension of the intermediate plate 52 in the Y direction is shorter than that of the actuator plate 53. Therefore, at both sides in the Y direction with respect to the intermediate plate 52, the end portions in the Y direction (for example, the first outer regions 81) of the actuator plate 53 are exposed. At the end portions in the Y direction of the actuator plate 53, the portions exposed from the intermediate plate 52 function as the crimping regions of the flexible printed circuit boards 100, 101.

[0119] In the intermediate plate 52, at a portion overlapping with the through - hole portion 75b of each ejection channel 75 in a plan view, communication holes 130 are formed. The communication holes 130 are the A - column communication holes 130A communicating with the ejection channel 75A and the B - column communication holes 130B communicating with the ejection channel 75B. The communication holes 130 communicate individually with the corresponding through - hole portions 75b of the ejection channels 75 on the surface side of the actuator plate 53. The communication holes 130 are formed in an oval shape with the Y direction as the length direction. The dimension of the communication holes 130 in the Y direction is shorter than that of the through - hole portion 75b. On the other hand, the dimension of the communication holes 130 in the X direction is wider than that of the through - hole portion 75b. However, the dimension of the communication holes 130 in the X direction may also be shorter than that of the through - hole portion 75b.

[0120] In the intermediate plate 52, at a position overlapping with the group separation groove 71 in a plan view, a first open groove 131 is formed. The first open groove 131 opens the group separation groove 71 and exposes the second outer region 86 of the first channel B - column 62 and the first outer region 81 of the second channel A - column 63. The first open groove 131 is formed in a strip shape extending in the X direction with a length equivalent to that of the group separation groove 71.

[0121] In the intermediate plate 52, at a position that overlaps with the column separation groove 72 in a plan view, a second open groove 132 is formed. The second open groove 132 at least opens the column separation groove 72. The second open groove 132 is formed in a strip shape extending in the X direction with a length equivalent to that of the column separation groove 72. In addition, as long as at least a part of the column separation groove 72 is opened by the second open groove 132, the length of the second open groove 132 in the Y direction may be narrower or wider than that of the column separation groove 72. In the present embodiment, the lengths of the second open groove 132 and the column separation groove 72 in the Y direction are respectively equivalent.

[0122] As Figure 4 shown, the nozzle plate 51 is fixed to the surface of the intermediate plate 52 by adhesion or the like. The width of the nozzle plate 51 in the Y direction is equivalent to that of the intermediate plate 52. In the present embodiment, the nozzle plate 51 is formed of a resin material such as polyimide with a thickness of about 50 μm. However, in addition to the resin material, the nozzle plate 51 may also be a single-layer structure or a laminated structure using a metal material (such as SUS or Ni-Pd), glass, silicon, etc.

[0123] In the nozzle plate 51, four nozzle rows (the first nozzle A row 141, the first nozzle B row 142, the second nozzle A row 143, and the second nozzle B row 144) extending in the X direction are formed at intervals in the Y direction.

[0124] Each nozzle row 141 - 144 has a plurality of nozzle holes (the first nozzle A hole 145, the first nozzle B hole 146, the second nozzle A hole 147, and the second nozzle B hole 148) penetrating the nozzle plate 51 in the Z direction. Each nozzle hole 145 - 148 is arranged at intervals in the X direction. Each nozzle hole 145 - 148 is formed in a tapered shape such that the inner diameter gradually decreases from the back side toward the front side. The maximum inner diameter of each nozzle hole 145 - 148 is equivalent to the width of the ejection channel 75 in the Y direction.

[0125] As Figure 6 , Figure 9 shown, the first nozzle A hole 145 is respectively communicated with the central part in the Y direction of the ejection channel 75A in the first channel A row 61 through the A row communication hole (the first communication hole) 130A. The first nozzle B hole 146 is respectively communicated with the central part in the Y direction of the ejection channel 75B in the first channel B row 62 through the B row communication hole (the second communication hole) 130B. The second nozzle A hole 147 is respectively communicated with the central part in the Y direction of the ejection channel 75A in the second channel A row 63 through the A row communication hole 130A. The second nozzle B hole 148 is respectively communicated with the central part in the Y direction of the ejection channel 75B in the second channel B row 64 through the B row communication hole 130B. Therefore, each non-ejection channel 76 is not communicated with the nozzle holes 145 - 148, but is covered by the nozzle plate 51 from the surface side.

[0126] [Method of operating Printer 1]

[0127] Next, a case where text, graphics, etc. are recorded on the recording medium P using the printer 1 configured as described above will be described below.

[0128] In addition, as an initial state, in Figure 1 the four ink tanks 4 shown are each sufficiently filled with inks of different colors. Further, the ink in the ink tank 4 becomes a state of being filled into the inkjet head 5 via the ink circulation mechanism 6.

[0129] In such an initial state, when the printer 1 is operated, the recording medium P is sandwiched between the rollers 11 and 12 of the conveyance mechanisms 2 and 3 and conveyed simultaneously in the +X direction. At the same time, the carriage 29 moves in the Y direction, so that the inkjet head 5 mounted on the carriage 29 reciprocates in the Y direction.

[0130] During the reciprocating movement of the inkjet head 5, ink is appropriately ejected from each inkjet head 5 onto the recording medium P. Thereby, it is possible to record text, images, etc. on the recording medium P.

[0131] Here, below, the operation of each inkjet head 5 will be described in detail.

[0132] In a circulation type side ejection type inkjet head 5 as in the present embodiment, first, Figure 2 the pressure pump 24 and the suction pump 25 shown are operated so that ink flows in the circulation flow path 23. In this case, the ink flowing through the ink supply pipe 21 is supplied to each ejection channel 75 through the inlet common ink chamber 120 and the inlet slit 125. The ink supplied to each ejection channel 75 flows in each ejection channel 75 in the Y direction. Thereafter, after the ink is discharged to the outlet common ink chamber 121 through the outlet slit 126, it returns to the ink tank 4 through the ink discharge pipe 22. Thereby, it is possible to circulate the ink between the inkjet head 5 and the ink tank 4.

[0133] Then, if the carriage 29 (refer to Figure 1The reciprocating movement of the inkjet head 5 is started by the movement of ( ), and the drive voltage is applied to the electrodes 95 and 97 via the flexible printed circuit boards 100 and 101. At this time, the individual electrode 97 is made the drive potential Vdd, and the common electrode 95 is made the reference potential GND, and the drive voltage is applied between the electrodes 95 and 97. Then, thickness sliding deformation occurs in the two drive walls 70 that delimit the ejection channel 75, and these two drive walls 70 are deformed so as to protrude toward the non-ejection channel 76 side. That is, a voltage is applied between the electrodes 95 and 97, whereby the drive wall 70 is bent and deformed in a V shape with the middle portion in the Z direction as the center. As a result, the volume of the ejection channel 75 increases. Then, since the volume of the ejection channel 75 increases, the ink stored in the inlet common ink chamber 120 is guided through the inlet slit 125 into the ejection channel 75. The ink guided into the inside of the ejection channel 75 becomes a pressure wave and propagates inside the ejection channel 75. When the pressure wave reaches the nozzle holes 145 - 148, the voltage applied between the electrodes 95 and 97 is made zero. As a result, the drive wall 70 returns to its original state, and the volume of the ejection channel 75 that has temporarily increased returns to its original volume. By this operation, the pressure inside the ejection channel 75 increases, and the ink is pressurized. As a result, the ink in droplet form is ejected to the outside through the communication holes 130 and the nozzle holes 145 - 148, and thus characters, images, etc. can be recorded on the recording medium P as described above.

[0134] <Method for manufacturing the head chip 50>

[0135] Next, the method for manufacturing the above-described head chip 50 will be described. In the following description, for convenience, the case of manufacturing the head chip 50 at the chip level will be described as an example. Figure 10 is an enlarged side view of the board assembly 200.

[0136] The method for manufacturing the head chip 50 includes a superposition process, a protective film formation process, and a nozzle plate attachment process. In addition, the necessary processing has been performed on each of the boards 51 - 54 before the superposition process.

[0137] In the lamination 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 in such a manner that the ejection channels 75 of each channel column 61 - 64 communicate with the corresponding slits 125 and 126. In addition, the actuator plate 53 and the intermediate plate 52 are bonded in such a manner that the ejection channels 75 of each channel column 61 - 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 the plate assembly 200. In this state, the ejection channels 75 communicate with the outside of the ejection channels 75 through the slits 125 and 126 and the communication holes 130. Regarding the non-ejection channels 76, in the outer regions 81 and 86, the through-holes 76a communicate with the outside of the non-ejection channels 76, and the openings 90a communicate with the outside of the non-ejection channels 76 through the column separation grooves 72 and the second opening grooves 132.

[0138] In the protective film forming process, a first protective film 110 is formed in the ejection channels 75, and a second protective film 111 is formed on the inner surface of the non-ejection channels 76. The protective films 110 and 111 are formed by depositing a p-xylene resin material, for example, by chemical vapor deposition (CVD). Specifically, in a state where the plate assembly 200 is set in a box body (not shown), a raw material gas that is a forming material for the protective films 110 and 111 is introduced. At this time, the raw material gas is introduced into the ejection channels 75 through the slits 125 and 126 or the communication holes 130. That is, the raw material gas is introduced from both end portions in the Y direction of the ejection channels 75 through the common ink chambers 120 and 121 and the slits 125 and 126 (refer to arrow Q1a). The raw material gas is introduced from the central portion in the Y direction of the ejection channels 75 through the communication holes 130 (refer to arrow Q1b). The raw material gas introduced into the ejection channels 75 adheres to the inner surface of the ejection channels 75, and thus the first protective film 110 accumulates on the inner surface of the ejection channels 75.

[0139] The raw material gas is introduced into the non-ejection channel 76 through the through-hole portion 76a or the communication portion 90. That is, the raw material gas is introduced into the non-ejection channel 76 through the portions (openings 53a, 53b) of the through-hole portion 76a that are open at the outer regions 81, 86 (refer to arrow Q2a). After the raw material gas enters the second open groove 132 and the column separation groove 72, it is introduced into the non-ejection channel 76 through the opening 90a (refer to arrow Q2b). In addition, the raw material gas that enters the column separation groove 72 is introduced into the non-ejection channel 76 through the opening 90a from the back side of the actuator plate 53 after entering the communication groove 127. The raw material gas introduced into the non-ejection channel 76 adheres to the inner surface of the non-ejection channel 76, thereby accumulating the second protective film 111. In addition, in the protective film forming process, if the protective films 110, 111 are formed at least on the inner surfaces of the channels 75, 76, the protective films may also accumulate on portions of the channels 75, 76 other than the inner surfaces.

[0140] Thereafter, in the nozzle plate attaching process, the nozzle plate 51 is bonded to the actuator plate 53 in such a manner that the nozzle holes 145 - 148 communicate with the ejection channels 75 of the corresponding channel columns 61 - 64 through the communication holes 130.

[0141] Through the above, the head chip 50 is manufactured.

[0142] In addition, the head chip 50 can also be manufactured at the wafer level. In the case of manufacturing at the wafer level, first, an actuator wafer to which a plurality of actuator plates 53 are connected, a cover wafer to which a plurality of cover plates 54 are connected, and an intermediate wafer to which a plurality of intermediate plates 52 are connected are joined to form a wafer joined body. Thereafter, after forming the protective films 110, 111 on the wafer joined body, the wafer joined body is cut to form a plurality of head chips 50.

[0143] In this way, in the present embodiment, as a configuration: in the same channel group (for example, the first channel group 66), the protective films 110, 111 are respectively formed on the inner surfaces of the ejection channels 75 and the non-ejection channels 76 of the first channel A column 61 and on the inner surfaces of the ejection channels 75 and the non-ejection channels 76 of the first channel B column 62.

[0144] According to this configuration, the protective films 110, 111 are formed on the inner surfaces of the ejection channel 75 and the non-ejection channel 76, thereby being able to suppress the contact between the electrodes 95, 97 formed on the inner surfaces of the ejection channel 75 and the non-ejection channel 76 and the ink. Thus, it is possible to suppress the short circuit of each electrode 95, 97 due to the ink and maintain excellent ejection performance in the long term.

[0145] Specifically, in the present embodiment, in the actuator plate 53, at both ends in the Y direction of the non-jetting channels 76A in the first channel A column 61, there are formed openings 53a, 90aA that communicate the inside and outside of the non-jetting channels 76A and can introduce the forming material of the second protective film 111 into the non-jetting channels 76A. On the other hand, as a configuration: in the actuator plate 53, at both ends in the Y direction of the non-jetting channels 76B in the first channel B column 62, there are formed openings 53b, 90aB that communicate the inside and outside of the non-jetting channels 76B and can introduce the forming material of the second protective film 111 into the non-jetting channels 76B.

[0146] According to this configuration, the forming material of the second protective film 111 is introduced into the non-jetting channels 76 through the openings 53a, 90aA and the openings 53b, 90aB, so that the second protective film 111 can also be effectively formed on the inner surface of the non-jetting channels 76.

[0147] As a result, it is possible to suppress, for example, an electrode short circuit or the like formed on the inner surface of the non-jetting channels 76 due to ink or the like entering the non-jetting channels 76.

[0148] Moreover, in the present embodiment, the forming material of the first protective film 110 is introduced into the jetting channels 75 through the slits 125, 126 and the communication holes 130, and the forming material of the second protective film 111 is introduced into the non-jetting channels 76 through the openings 53a, 53b, 90a. Thus, the protective films 110, 111 can be effectively formed on the inner surfaces of the jetting channels 75 and the non-jetting channels 76.

[0149] In the present embodiment, as a configuration: in the actuator plate 53 and the intermediate plate 52, there are formed a column separation groove 72 and a second opening groove 132 that communicate the opening 90aA of the non-jetting channel 76A in the first channel A column 61 with the opening 90aB of the non-jetting channel 76B in the first channel B column 62.

[0150] According to this configuration, the raw material gas of the second protective film 111 is introduced into each non-jetting channel 76 through the column separation groove 72 and the second opening groove 132 via the opening 90a. Thus, compared with the case where the forming material of the protective film is separately introduced into each non-jetting channel 76 through each opening 90a, the second protective film 111 can be formed efficiently.

[0151] In the present embodiment, as a configuration in which a communication groove 127 communicating with the column separation groove 72 is formed in the cover plate 54.

[0152] According to this configuration, in the board assembly 200, the pressure loss in the space reaching each opening 90a can be reduced, so that the raw material gas of the second protective film 111 can be efficiently introduced into the non-jetting channel 76 through each opening 90a.

[0153] In the present embodiment, the width of the communication groove 127 in the X direction is wider than that of the column separation groove 72, and the communication groove 127 communicates with the opening 90a from the back side of the actuator plate 53.

[0154] According to this configuration, the raw material gas of the second protective film 111 that enters the communication groove 127 through the column separation groove 72 is introduced into each non-jetting channel 76 from the back side of the actuator plate 53 through the opening 90a. Thus, the raw material gas of the second protective film 111 is directly introduced into each non-jetting channel 76 through the column separation groove 72 or indirectly through the communication groove 127. As a result, the second protective film 111 can be efficiently formed on the inner surface of the non-jetting channel 76.

[0155] In the present embodiment, as a configuration: in the cover plate 54, a beam portion 128 is provided between adjacent inlet common ink chambers 120.

[0156] According to this configuration, it becomes easy to ensure the strength of the cover plate 54 through the beam portion 128. Therefore, when the actuator plate 53 and the cover plate 54 are bonded, 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 joined, and leakage of ink between the actuator plate 53 and the cover plate 54 can be suppressed.

[0157] In addition, by forming the communication groove 127 in the beam portion 128, it becomes easy to ensure the depth of the communication groove 127. Therefore, the raw material gas of the second protective film 111 can be efficiently introduced into the non-jetting channel 76 through each opening 90a.

[0158] In the present embodiment, the upper cut portion 76b of the first channel A column 61 crosses the column separation groove 72 in the Y direction, and the communication portion with the column separation groove 72 constitutes the opening 90aA. The upper cut portion 76b of the first channel B column 62 crosses the column separation groove 72 in the Y direction, and the communication portion with the column separation groove 72 constitutes the opening 90aB.

[0159] According to this configuration, it is easier to ensure the opening area of the opening compared with the case where the column separation groove 72 communicates with the end portion of the upper cut portion 76b. Thus, the raw material gas of the second protective film 111 can be efficiently introduced into the non-jetting channel 76 through each opening 90a.

[0160] In the inkjet head 5 and the printer 1 of the present embodiment, the above-described head chip 50 is provided, so that short-circuiting of the electrodes due to ink can be suppressed, and excellent ejection performance can be maintained over a long period of time.

[0161] (Second Embodiment)

[0162] In Figure 11 In the head chip 50 shown, the communication groove 127 is provided at the central portion in the Y direction of the beam portion 128. The width D1 in the Y direction in the communication groove 127 is narrower than the width D2 in the Y direction in the beam portion 128. Therefore, on the surface of the beam portion 128, the portion located outside the communication groove 127 functions as a pressure-receiving area T1 that engages with the actuator plate 53. In addition, the bottom surface of the inlet common ink chamber 120 is located on the back side relative to the top surface of the communication groove 127. Therefore, the inlet common ink chamber 120 and the communication groove 127 are arranged offset in the Z direction (do not overlap).

[0163] In the present embodiment, a pressure-receiving area T1 is provided in the portion of the beam portion 128 located outside the communication groove 127. The pressure-receiving area T1 functions as a pressure-receiving surface that bears the load acting between the actuator plate 53 and the cover plate 54 when the actuator plate 53 and the cover plate 54 are bonded. Thereby, a bonding load can be effectively applied between the actuator plate 53 and the cover plate 54. As a result, the actuator plate and the cover plate can be joined more reliably.

[0164] As Figure 12 shown, the inlet common ink chamber 120 and the communication groove 127 may also overlap in the Z direction. Thereby, it becomes easy to ensure the depth of the communication groove 127, and thus the source gas of the second protective film 111 can be efficiently introduced into the non-ejection channel 76 through each opening 90a.

[0165] Furthermore, the technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be added without departing from the spirit of the present disclosure.

[0166] For example, in the above-described embodiment, as an example of a liquid ejection recording apparatus, an inkjet printer 1 is illustrated, but it is not limited to a printer. For example, it may also be a facsimile or a digital press, etc.

[0167] In the above-described embodiment, a configuration in which the inkjet head moves relative to the recording medium during printing (so-called shuttle machine) is illustrated as an example, but it is not limited to this configuration. The configuration related to the present disclosure can also be adopted in a configuration in which the recording medium moves relative to the inkjet head in a state where the inkjet head is fixed (so-called fixed head machine).

[0168] In the above-described embodiment, the case where the recording medium P is paper has been described, but the configuration is not limited thereto. The recording medium P is not limited to paper, and may be a metal material, a resin material, or food, etc.

[0169] In the above-described embodiment, the configuration in which the liquid ejection head is mounted on the liquid ejection recording apparatus has been described, but the configuration is not limited thereto. That is, the liquid ejected from the liquid ejection head is not limited to the liquid that hits the recording medium, and may be, for example, a liquid medicine used in compounding, a food additive such as a seasoning or a flavor added to food, an aromatic agent ejected into the air, etc.

[0170] In the above-described embodiment, the configuration in which the Z direction coincides with the direction of gravity has been described, but the configuration is not limited thereto, and the Z direction may be along the horizontal direction.

[0171] In the above-described embodiment, as the following configuration: in the first channel A column 61 and the first channel B column 62 (or the second channel A column 63 and the second channel B column 64), the non-ejection channels 76 of the first channel A column 61 and the non-ejection channels 76 of the first channel B column 62 open at the common column separation groove 72. However, the non-ejection channels 76 of the first channel A column 61 and the non-ejection channels 76 of the first channel B column 62 may also communicate the inside and outside of the non-ejection channels 76 through different grooves respectively.

[0172] In the above-described embodiment, the configuration in which the width of the communication groove 127 in the cover plate 54 is wider than that of the column separation groove 72 has been described, but the width of the communication groove 127 may be wider than that of the column separation groove 72 or may be narrower than that of the column separation groove 72. In addition, the cover plate 54 may also be a configuration without the communication groove 127.

[0173] In the above-described embodiment, as long as the non-ejection channel 76 communicates with the outside at both ends, it may also communicate through a portion other than the opening 53a, 90a.

[0174] In the above-described embodiment, the electrode protection protective film has been described as an example, but the protective film may be formed regardless of the presence or absence of the electrode.

[0175] In the above-described embodiment, the configuration in which the inlet common ink chamber 120 is provided for each channel column has been described, but the configuration is not limited thereto. For example, as Figure 13As shown, it is also possible to share a common inlet ink chamber 120 for adjacent channel columns 61 and 62. In this case, in the common inlet ink chamber 120, an inlet slit 125 communicating with the ejection channel 75A of one channel column 61 and an inlet slit 125 communicating with the ejection channel 75B of another channel column 62 are open. In such a configuration, it is also possible to form a communication groove 127 on the surface of the cover plate 54 at a position (a portion on the -Z side with respect to the common inlet ink chamber 120) that overlaps with the column separation groove 72 in a top view.

[0176] In addition, within the scope not departing from the gist of the present disclosure, the constituent elements in the above-described embodiments can be appropriately replaced with well-known constituent elements, and further, the above-described various modification examples can be appropriately combined.

[0177] Reference Signs

[0178] 1... Inkjet printer (liquid ejection recording device)

[0179] 5... Inkjet head (liquid ejection head)

[0180] 50... Head chip

[0181] 52... Intermediate plate (communication plate)

[0182] 53... Actuator plate

[0183] 53a... Opening (first opening, first outer opening, opening)

[0184] 53b... Opening (second opening, second outer opening, opening)

[0185] 54... Cover plate

[0186] 61... First channel A column (first channel region)

[0187] 62... First channel B column (second channel region)

[0188] 63... Second channel A column (first channel region)

[0189] 64... Second channel B column (second channel region)

[0190] 72... Column separation groove (common groove)

[0191] 75... Ejection channel (first ejection channel, second ejection channel, ejection channel)

[0192] 75A... Ejection channel (first ejection channel, ejection channel)

[0193] 75B... Ejection channel (second ejection channel, ejection channel)

[0194] 76... Non-jetting channels (first non-jetting channel, second non-jetting channel, non-jetting channel)

[0195] 76A... Non-jetting channels (first non-jetting channel, jetting channel)

[0196] 76B... Non-jetting channels (second non-jetting channel, jetting channel)

[0197] 76a... Through portion (first extension portion, second extension portion)

[0198] 76b... Upper cut portion (first upper cut portion, second upper cut portion)

[0199] 90a... Openings (opening, first inner opening, second inner opening)

[0200] 90aA... Openings (first opening, first inner opening, opening)

[0201] 90aB... Openings (second opening, second inner opening, opening)

[0202] 110... First protective film (protective film)

[0203] 111... Second protective film (protective film)

[0204] 120... Inlet common ink chamber (first common flow path, second common flow path)

[0205] 125... Inlet slit (first liquid flow path, second liquid flow path, liquid flow path)

[0206] 126... Outlet slit (first liquid flow path, second liquid flow path, liquid flow path)

[0207] 127... Connecting groove

[0208] 128... Beam portion

[0209] 130A... Connecting holes (first connecting hole, connecting hole)

[0210] 130B... Connecting holes (second connecting hole, connecting hole).

Claims

1. A head chip, comprising: An actuator plate having a first channel region in which a first ejection channel and a first non-ejection channel extending in the first direction are arranged side by side in a second direction intersecting the first direction, and a second channel region in which a second ejection channel and a second non-ejection channel extending in the first direction are arranged in the second direction; A 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 overlapping with the actuator plate; And A connection plate having a first connection hole communicating with the first ejection channel at a central portion in the first direction and a second connection hole communicating with the second ejection channel at a central portion in the first direction, overlapping with the actuator plate on a side opposite to the cover plate, On inner surfaces of the first ejection channel, the first non-ejection channel, the second ejection channel, and the second non-ejection channel, protective films are respectively formed. In the actuator plate, at both ends in the first direction in the first non-ejection channel, first openings are formed to communicate the inside and outside of the first non-ejection channel. In the actuator plate, at both ends in the first direction in the second non-ejection channel, second openings are formed to communicate the inside and outside of the second non-ejection channel.

2. The head chip according to claim 1, wherein The first opening includes: A first inner opening located at an end of the first non-ejection channel on the side of the second channel region in the first direction; and A first outer opening located at an end of the first non-ejection channel on a side opposite to the second channel region side in the first direction, The second opening includes: A second inner opening located at an end of the second non-ejection channel on the side of the first channel region in the first direction; and A second outer opening located at an end of the second non-ejection channel on a side opposite to the first channel region side in the first direction, At a boundary portion between the first channel region and the second channel region in the first direction in the actuator plate and the connection plate, a common groove is formed to communicate the first inner openings in the plurality of first non-ejection channels and the second inner openings in the plurality of second non-ejection channels and extend in the second direction.

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

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

5. The head chip according to claim 3 or claim 4, wherein The cover plate includes: A first common flow path communicating with the plurality of first liquid flow paths together; and A second common flow path communicating with the plurality of second liquid flow paths together. The portion of the cover plate between the first liquid flow path and the second common flow path forms a beam portion that separates between the first common flow path and the second common flow path and extends in the second direction.

6. The head chip according to claim 5, wherein, the communication groove is formed in the beam portion, the width of the communication 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 coincides with the first common flow path and the second common flow path in the coincidence direction in which the actuator plate coincides with the cover plate.

8. The head chip according to any one of claims 2 to 4, wherein, the first non-injection channel includes: a first extension portion extending in the first direction; and a first upper cut portion whose groove depth gradually becomes shallower as it faces the second channel region side in the first direction from the first extension portion, the second non-injection channel includes: a second extension portion extending in the first direction; and a second upper cut portion whose groove depth gradually becomes shallower as it faces the first channel region side in the first direction from the second extension portion, the first upper cut portion traverses the common groove in the first direction, and the communication portion with the common groove constitutes the first inner opening, the second upper cut portion traverses the common groove in the first direction, and the communication portion with the common groove constitutes the second inner opening.

9. A liquid ejection head including the head chip according to any one of claims 1 to 8.

10. A liquid ejection recording apparatus including the liquid ejection head according to claim 9.

11. A method for manufacturing a head chip, which is a method for manufacturing a head chip having: an actuator plate in which ejection channels and non-ejection channels extending in the first direction are arranged in a second direction intersecting the first direction; a cover plate having a liquid flow path communicating with the ejection channels and coinciding with the actuator plate; and a communication plate having communication holes communicating with the ejection channels at the central portion in the first direction, and coinciding with the actuator plate on the side opposite to the cover plate, wherein, in the actuator plate, at both ends in the first direction of the non-ejection channels, openings for communicating the inside and outside of the non-ejection channels are formed, a protective film forming step of forming a protective film on the inner surfaces of the ejection channels and the non-ejection channels is provided, in the protective film forming step, the forming material of the protective film is introduced into the ejection channels through the liquid flow path and the communication holes, and the forming material of the protective film is introduced into the non-ejection channels through the openings.

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