Method for manufacturing a liquid ejection head chip, liquid ejection head chip, liquid ejection head, and liquid ejection recording apparatus

Abstract

Provided are a method for manufacturing a liquid ejection head chip, a liquid ejection head chip, a liquid ejection head, and a liquid ejection recording apparatus. The man-hour for removing a protective film such as a parylene film of an unnecessary portion is reduced. A method for manufacturing a head chip according to one aspect of the present disclosure includes: a substrate preparation step of preparing an actuator plate substrate having an ejection passage communicating with a nozzle hole for ejecting ink and a non-ejection passage that does not eject ink; and a protective film formation step of forming, after the substrate preparation step, a protective film that protects a common electrode formed on an inner surface of the ejection passage from the influence of ink in a state where the ejection passage is exposed and the non-ejection passage is covered.

Description

Technical Field

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

[0002] Conventionally, as an apparatus for ejecting droplet-like ink onto a recording medium such as recording paper to record an image or characters on the recording medium, there has been an inkjet printer equipped with an inkjet head.

[0003] For example, regarding an inkjet head, there is a method of ejecting ink by applying a voltage to a piezoelectric body such as PZT (lead zirconate titanate) to deform it. In order to perform finer printing, a method of increasing the density of nozzle holes for ejecting ink is adopted. At this time, in order to increase the density, a plurality of channels and the like of an actuator plate (the structure of a head chip) are also miniaturized.

[0004] For example, a protective film such as a parylene (registered trademark) film is formed on a portion of the inkjet head that comes into contact with ink to ensure durability. For example, by forming a parylene film in the channels, corrosion of the electrodes formed in the channels by ink is suppressed. Since parylene has the advantage of adhering to a complex structure, it is sometimes formed in parts other than the required parts (unnecessary parts) such as inside the channels. For example, Japanese Patent Application Laid-Open No. 2005-153510 discloses a method of removing a parylene film formed in an unnecessary part by an oxygen plasma etching process.

[0005] On the other hand, there is a method in which, during the formation of the parylene film, an unnecessary part is covered with a masking member such as a tape, and the masking member is removed physically after the parylene film is formed.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2005-153510. Summary of the Invention

[0009] (Problems to be Solved by the Invention)

[0010] However, if the parylene film formed in an unnecessary part is removed by an oxygen plasma etching process, ozone is generated during the removal, and there is a possibility of affecting the parylene film formed in a required part.

[0011] On the other hand, if the masking member is removed physically after the parylene film is formed, the parylene film may be broken and fuzzing may occur during the removal.

[0012] As described above, in order to ensure durability, the peripheral area of the nozzle holes of the ink to be ejected becomes a part that requires a protective film such as a parylene film. On the other hand, areas other than the peripheral area of the nozzle holes, including the area connecting to the external substrate, etc., become parts that do not require a protective film such as a parylene film.

[0013] Therefore, it is required to reduce the man-hours for removing the protective film such as the parylene film from the unnecessary parts.

[0014] An object of the present disclosure is to provide a method for manufacturing a liquid ejection head chip, a liquid ejection head chip, a liquid ejection head, and a liquid ejection recording apparatus that can reduce the man-hours for removing the protective film such as the parylene film from the unnecessary parts.

[0015] (Means for Solving the Problem)

[0016] In order to solve the above problems, the present disclosure adopts the following method.

[0017] (1) A method for manufacturing a liquid ejection head chip according to one aspect of the present disclosure includes: a substrate preparation step of preparing an actuator plate substrate having an ejection channel communicating with a nozzle hole for ejecting a liquid and a non-ejection channel that does not eject the liquid; and a protective film formation step of forming, after the substrate preparation step, a protective film that protects an electrode formed on an inner surface of the ejection channel from the influence of the liquid in a state where the ejection channel is exposed and the non-ejection channel is covered.

[0018] According to this aspect, the protective film is formed on the exposed ejection channel in a state where the non-ejection channel is covered, so that the formation of the protective film on the non-ejection channel can be suppressed. The non-ejection channel is a part that does not require a protective film, so that the man-hours for removing the protective film from the unnecessary parts can be reduced.

[0019] (2) In the method for manufacturing a liquid ejection head chip according to the aspect (1) above, it is preferable that the actuator plate substrate has a first surface on which a nozzle plate is disposed, the nozzle plate has a nozzle hole communicating with the ejection channel, and in the protective film formation step, after disposing a mask having an opening for exposing the ejection channel on the first surface of the actuator plate substrate, the protective film is formed on the ejection channel through the opening.

[0020] According to this aspect, the formation of the protective film on the non-ejection channel can be suppressed by a simple method using a mask.

[0021] (3) In the method for manufacturing a liquid ejection head chip according to the method of (2) above, it is preferable that the substrate for the actuator plate further has a second surface intersecting the aforementioned first surface. In the aforementioned protective film forming step, after disposing the aforementioned mask across the aforementioned first surface and the aforementioned second surface of the substrate for the actuator plate, the aforementioned protective film is formed in the aforementioned ejection channel through the aforementioned opening.

[0022] Assuming that the mask is only disposed on the first surface of the substrate for the actuator plate, the protective film may be formed at an unwanted portion through the gap between the mask and the first surface. In contrast, according to this method, the mask is disposed across the first surface and the second surface of the substrate for the actuator plate, thereby covering the aforementioned gap with the mask, and thus it is possible to suppress the formation of the protective film at an unwanted portion.

[0023] (4) In the method for manufacturing a liquid ejection head chip according to the method of (2) or (3) above, it is preferable that in the aforementioned protective film forming step, after joining an intermediate plate having a communication hole communicating with the aforementioned ejection channel to the aforementioned first surface of the substrate for the actuator plate as the aforementioned mask, the aforementioned protective film is formed in the aforementioned ejection channel through the aforementioned communication hole.

[0024] According to this method, the intermediate plate is a component of the liquid ejection head chip, and the intermediate plate can be left as it is after the protective film forming step. Therefore, it is possible to suppress the formation of the protective film in non-ejection channels by a simpler method.

[0025] (5) In the method for manufacturing a liquid ejection head chip according to the method of (4) above, it is preferable that the aforementioned first surface of the substrate for the actuator plate has a nozzle peripheral region around the aforementioned nozzle hole and a connection region for connecting to an external substrate. In the aforementioned protective film forming step, in a state where the aforementioned intermediate plate as the aforementioned mask is disposed in the aforementioned nozzle peripheral region and the aforementioned connection region is covered with a connection region mask as the aforementioned mask, the aforementioned protective film is formed in the aforementioned ejection channel through the aforementioned communication hole.

[0026] According to this method, the connection region suppresses the formation of the protective film, and thus it is possible to suppress poor connection of the external substrate.

[0027] (6) In the method for manufacturing a liquid ejection head chip according to the method of (5) above, it is preferable that before the aforementioned protective film forming step, a stepped portion is formed at a portion of the aforementioned intermediate plate that divides the aforementioned nozzle peripheral region and the aforementioned connection region.

[0028] According to this method, the alignment of the connection region mask can be performed by the stepped portion. Furthermore, even if fuzzing of the protective film occurs when removing the connection region mask, the fuzzing can be suppressed from affecting the nozzle peripheral region. Furthermore, in the case of manufacturing a liquid ejection head, the alignment of the nozzle plate can be performed by the stepped portion.

[0029] (7) The liquid ejection head chip according to one aspect of the present disclosure includes an actuator plate having an ejection channel communicating with a nozzle hole for ejecting liquid and a non-ejection channel for not ejecting the liquid. The actuator plate has a protective film for protecting an electrode formed on an inner surface of the ejection channel from the influence of the liquid. The protective film satisfies any one of the following (A) or (B):

[0030] (A) The protective film is not formed in the non-ejection channel;

[0031] (B) The protective film is also formed in the non-ejection channel, and the thickness of the protective film in the non-ejection channel is smaller than the thickness of the protective film in the ejection channel.

[0032] According to this aspect, the non-ejection channel is a part where the protective film is not required, so that the man-hours for removing the protective film of the unnecessary part can be reduced.

[0033] (8) In the liquid ejection head chip according to the aspect (7) above, it is preferable that the protective film satisfies the above (A).

[0034] According to this aspect, the man-hours for removing the protective film of the unnecessary part are not spent. Furthermore, the problem of the protective film fraying does not occur.

[0035] (9) In the liquid ejection head chip according to the aspect (8) above, it is preferable that the actuator plate has a nozzle peripheral region around the nozzle hole and a connection region for connecting to an external substrate, and the protective film is not formed in the connection region.

[0036] According to this aspect, poor connection of the external substrate can be suppressed.

[0037] (10) In the liquid ejection head chip according to the aspect (9) above, it is preferable to further include an intermediate plate that is joined to the actuator plate and has a communication hole communicating with the ejection channel. The intermediate plate has a stepped portion at a position dividing the nozzle peripheral region and the connection region.

[0038] According to this aspect, in the case of manufacturing a liquid ejection head, the alignment of the nozzle plate can be performed by the stepped portion.

[0039] (11) The liquid ejection head according to one aspect of the present disclosure includes the liquid ejection head chip according to any one of the aspects (7) to (10) above.

[0040] According to this aspect, since the liquid ejection head chip according to the above aspect is included, a liquid ejection head capable of reducing the man-hours for removing the protective film of the unnecessary part can be provided.

[0041] A liquid ejection recording apparatus according to one aspect of the present disclosure includes the liquid ejection head according to the aspect (11) above.

[0042] According to this aspect, since the liquid ejection head according to the above aspect is provided, a liquid ejection recording apparatus capable of reducing the man-hours for removing the protective film of unnecessary portions can be provided.

[0043] (Advantages of the Invention)

[0044] According to one aspect of the present disclosure, the man-hours for removing a protective film such as a parylene film of unnecessary portions can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a schematic configuration diagram of an inkjet printer according to an embodiment.

[0046] Figure 2 is a schematic configuration diagram of an inkjet head and an ink circulation mechanism according to an embodiment.

[0047] Figure 3 is an exploded perspective view of an actuator plate, a cover plate, and a nozzle plate according to an embodiment.

[0048] Figure 4 is a top view of an actuator plate according to an embodiment.

[0049] Figure 5 is a top view of an actuator plate and an intermediate plate according to an embodiment.

[0050] Figure 6 is [[ID=�6]] Figure 4 a cross-sectional view taken along line VI-VI.

[0051] Figure 7 is a bottom view of an actuator plate according to an embodiment.

[0052] Figure 8 is along Figure 7 a cross-sectional view of the inkjet head taken along line VIII-VIII.

[0053] Figure 9 is along Figure 7 a cross-sectional view of the inkjet head taken along line IX-IX.

[0054] Figure 10 is along Figure 7 a cross-sectional view of the actuator plate and the cover plate taken along line X-X.

[0055] Figure 11 is a bottom view of an intermediate plate according to an embodiment.

[0056] Figure 12 is Figure 11Section XII-XII of FIG.

[0057] Figure 13 This is a flowchart of a method for manufacturing an inkjet head according to an embodiment.

[0058] Figure 14 It is an explanatory diagram of the mask arrangement process involved in the embodiment.

[0059] Figure 15 yes Figure 14 XV-XV cross-section of FIG.

[0060] Figure 16 It is a bottom view of the nozzle plate according to the embodiment.

[0061] Figure 17 It is an explanatory diagram of a mask placement process according to a comparative example.

[0062] Figure 18 yes Figure 17 XVIII-XVIII cross-section diagram.

[0063] Figure 19 yes Figure 18 Cross-sectional view after removing the mask.

[0064] Figure 20 yes Figure 14 XX-XX cross-sectional view.

[0065] Figure 21 yes Figure 20 Cross-sectional view after removing the mask.

[0066] Figure 22 It is a cross-sectional view of a step portion of an intermediate plate according to a modification of the embodiment. DETAILED DESCRIPTION

[0067] Hereinafter, the embodiments involved in the present disclosure will be described with reference to the accompanying drawings. In the embodiments or modifications described below, the same symbols are sometimes assigned to corresponding structures and the description is omitted. In addition, in the following description, expressions such as "parallel" or "orthogonal", "center", "coaxial", etc. that show relative or absolute configurations not only indicate strictly such configurations, but also indicate a state of relative displacement at an angle or distance with a tolerance or a degree that can achieve the same function. In the following embodiment, as an example of a liquid jet recording device having a liquid jet head having a liquid jet head chip (hereinafter simply referred to as a head chip) disclosed in the present disclosure, an inkjet printer (hereinafter simply referred to as a printer) that uses ink (liquid) to record on a recording medium is described. In addition, in the drawings used in the following description, the proportions of each component are appropriately changed to make each component a recognizable size.

[0068] Printer

[0069] Figure 1 This is a schematic configuration diagram of printer 1.

[0070] As Figure 1 shown, the printer 1 of the present embodiment includes: a pair of conveyance mechanisms 2 and 3; an ink tank 4; an inkjet head 5 (liquid ejection head); an ink circulation mechanism 6; and a scanning mechanism 7. Further, in Figure 1 , the housing of the printer 1 is shown by a two-dot chain line to show the inside of the housing.

[0071] Further, in the following description, an X, Y, Z orthogonal coordinate system is used for description as required. The X direction coincides with the conveyance direction (sub-scanning direction) of the recording medium P (for example, paper, etc.). The Y direction coincides with the scanning direction (main scanning direction) of the scanning mechanism 7. The Z direction shows the up-and-down direction (gravity direction) orthogonal to the X direction and the Y direction. In the following description, the arrow side in the drawing among the X direction, Y direction, and Z direction is set as the positive (+) side, and the side opposite to the arrow is set as the negative (-) side for description. In this specification, the +Z side corresponds to the upper side in the gravity direction, and the -Z side corresponds to the lower side in the gravity direction.

[0072] The conveyance mechanisms 2 and 3 (first conveyance mechanism 2 and second conveyance mechanism 3) convey the recording medium P in the X direction (for example, +X side). Specifically, the first conveyance mechanism 2 includes: a first grid roller 11 extending in the Y direction; a first pressing roller 12 extending parallel to the first grid roller 11; and a drive mechanism (not shown) such as a motor that rotates the first grid roller 11 about an axis. The second conveyance mechanism 3 includes: a second grid roller 13 extending parallel to the first grid roller 11; a second pressing roller 14 extending parallel to the second grid roller 13; and a drive mechanism (not shown) that rotates the second grid roller 13 about an axis.

[0073] A plurality of ink tanks 4 are arranged side by side in the X direction. In the embodiment, the plurality of ink tanks 4 are ink tanks 4Y, 4M, 4C, and 4K that respectively contain inks of four colors: yellow, magenta, cyan, and black.

[0074] Figure 2 This is a schematic configuration diagram of the inkjet head and the ink circulation mechanism.

[0075] As Figure 2 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: an ink supply pipe 21 and an ink discharge pipe 22 that form a circulation flow path 23; a pressure pump 24 connected to the ink supply pipe 21; and a suction pump 25 connected to the ink discharge pipe 22. For example, the ink supply pipe 21 and the ink discharge pipe 22 are formed of a flexible hose that can follow the scanning mechanism 7 that supports the inkjet head 5 (refer to Figure 1The flexibility of the degree of movement of ().

[0076] The pressurizing pump 24 pressurizes the inside of the ink supply pipe 21, and sends the ink to the inkjet head 5 through the ink supply pipe 21. Thus, the ink supply pipe 21 side becomes a positive pressure with respect to the inkjet head 5.

[0077] The suction pump 25 decompresses the inside of the ink discharge pipe 22, and sucks the ink from the inkjet head 5 through the inside of the ink discharge pipe 22. Thus, the ink discharge pipe 22 side becomes a negative pressure with respect to the inkjet head 5. By driving the pressurizing pump 24 and the suction pump 25, the ink can circulate between the inkjet head 5 and the ink tank 4 through the circulation flow path 23.

[0078] As Figure 1 shown, the scanning mechanism 7 reciprocally scans the inkjet head 5 in the Y direction. Specifically, the scanning mechanism 7 includes: a pair of guide rails 31, 32 extending in the Y direction, a carriage 33 movably supported by the pair of guide rails 31, 32, and a drive mechanism 34 that moves the carriage 33 in the Y direction. In addition, the conveyance mechanisms 2, 3 and the scanning mechanism 7 function as a moving mechanism that relatively moves the inkjet head 5 and the recording medium P.

[0079] The drive mechanism 34 is disposed between the guide rails 31, 32 in the X direction. The drive mechanism 34 includes: a pair of pulleys 35, 36 disposed at intervals in the Y direction; an endless belt 37 wound between the pair of pulleys 35, 36; and a drive motor 38 that rotationally drives one pulley 35.

[0080] The carriage 33 is connected to the endless belt 37. A plurality of inkjet heads 5 are mounted side by side on the carriage 33 in the Y direction. In the embodiment, the plurality of inkjet heads 5 are inkjet heads 5Y, 5M, 5C, 5K that respectively eject inks of four colors: yellow, magenta, cyan, and black.

[0081] [Inkjet head]

[0082] Figure 3 is an exploded perspective view of the actuator plate 50, the cover plate 60, and the nozzle plate 41. Figure 4 is a top view of the actuator plate 50. Figure 5 is a top view of the actuator plate 50 and the intermediate plate 42. Figure 6 is Figure 4 the VI-VI sectional view of. In addition, in Figure 3 the illustration of the intermediate plate 42 is omitted. In Figure 4 the nozzle rows Nr1, Nr2 (the first nozzle row Nr1 and the second nozzle row Nr2) are shown by dotted lines. In Figure 5 the first nozzle row Nr1 is shown by dotted lines.

[0083] As Figure 3As shown, the inkjet head 5 includes a head chip 40 and a nozzle plate 41. The inkjet head 5 is a so-called side shoot type inkjet head in which ink passes in the thickness direction of the actuator plate 50, that is, in the depth direction of the ejection channel 51.

[0084] [Head chip]

[0085] The head chip 40 includes an actuator plate 50 and a cover plate 60. Although not shown, a protective film such as a parylene film is formed at required parts on the surface (including the inner surface) of the head chip 40.

[0086] [Actuator plate]

[0087] The outer shape of the actuator plate 50 is a rectangular plate shape having a long side in the X direction and a short side in the Y direction. The lower surface (-Z side surface) of the actuator plate 50 is a surface on which the nozzle plate 41 is arranged via an intermediate plate 42 (see Figure 6 ).

[0088] The actuator plate 50 includes, for example, any one or two or more of piezoelectric materials. The type of the piezoelectric material is not particularly limited, and for example, it is lead zirconate titanate (PZT) or the like. The actuator plate 50 of the embodiment is a so-called chevron type laminated substrate in which two piezoelectric substrates having different polarization directions in the thickness direction (Z direction) are laminated.

[0089] The actuator plate 50 has a plurality of rows (for example, two rows in the present embodiment) of channel rows Ch1, Ch2 arranged at a predetermined interval in the Y direction. Hereinafter, one of the two channel rows Ch1, Ch2 is also referred to as the first channel row Ch1, and the other is referred to as the second channel row Ch2. In addition, when it is not necessary to particularly distinguish, the two channel rows Ch1, Ch2 are referred to as channel rows for explanation.

[0090] As Figure 4 shown, the channel rows extend in the X direction. The channel rows include a plurality of channels 51, 52 extending in the Y direction and arranged at intervals in the X direction. Each of the channels 51, 52 is defined by a drive wall Wd including a piezoelectric body. The plurality of channels 51, 52 include ejection channels 51 for ejecting ink and non-ejection channels 52 for not ejecting ink. The ejection channels 51 and the non-ejection channels 52 are alternately arranged in the X direction.

[0091] The ejection channels 51 and the non-ejection channels 52 of the first channel row Ch1 and the ejection channels 51 and the non-ejection channels 52 of the second channel row Ch2 are arranged such that they are different from each other in the X direction. That is, the ejection channels 51 of each of the channel rows Ch1, Ch2 and the non-ejection channels 52 are arranged in a staggered manner in the X direction.

[0092] Figure 7 is a bottom view of the actuator plate 50. Figure 8is a cross-sectional view of the inkjet head 5 along line VIII-VIII of Figure 7 . Figure 9 is a cross-sectional view of the inkjet head 5 along line IX-IX of Figure 7 . Figure 10 is a cross-sectional view of the actuator plate 50 and the cover plate 60 along line X-X of Figure 7 .

[0093] As Figure 7 shown, the lower surface of the actuator plate 50 has: a nozzle peripheral region Ra around the periphery of the nozzle hole 41a (see Figure 8 ); and a connection region Rc for connecting the external substrate 45 (see Figure 3 ).

[0094] The nozzle peripheral region Ra is the region of the lower surface of the actuator plate 50 that faces the nozzle plate 41 (see Figure 8 ). The connection region Rc is the region of the lower surface of the actuator plate 50 that does not face the nozzle plate 41. The connection region Rc is arranged more outward in the Y direction than the nozzle peripheral region Ra. The connection region Rc is provided at the end of the actuator plate 50 in the Y direction (hereinafter, also referred to as the tail 50Y). In addition, the protective film is not formed in the connection region Rc.

[0095] The ejection channel 51 is provided in the nozzle peripheral region Ra. The ejection channel 51 is not provided in the connection region Rc. When viewed from the Z direction, the ejection channel 51 has a rectangular shape extending in the Y direction. For example, the protective film 70 is formed on the inner surface of the ejection channel 51.

[0096] In Figure 8 the cross-sectional view, the ejection channel 51 has an extension portion 51a extending in the Y direction and an upper cut portion 51b continuous with the extension portion 51a in the Y direction. The extension portion 51a has the same groove depth throughout the Y direction. The upper cut portion 51b gradually becomes shallower in groove depth as it moves from both ends of the extension portion 51a toward the outside in the Y direction.

[0097] As Figure 7 shown, the non-ejection channel 52 is provided across the nozzle peripheral region Ra and the connection region Rc. The non-ejection channel 52 extends throughout the Y direction of the actuator plate 50. In Figure 9 the cross-sectional view, the non-ejection channel 52 has the same groove depth throughout the Y direction. In addition, the protective film 70 (see Figure 7 ) is not formed in the non-ejection channel 52.

[0098] As Figure 6As shown, drive electrodes 55 extending in the Y direction are provided on the sides of each of the plurality of drive walls Wd. The drive electrodes 55 are electrodes for electrically driving (deforming) the drive walls Wd so that the plurality of ejection channels 51 function as pressure chambers. The drive electrodes 55 include: a pair of common electrodes 56 provided on the side surface of the drive wall Wd (inner surface of the ejection channel 51) that defines the ejection channel 51; and a pair of individual electrodes 57 provided on the side surface of the drive wall Wd (inner surface of the non-ejection channel 52) that defines the non-ejection channel 52.

[0099] A pair of common electrodes 56 opposed to each other within the same ejection channel 51 are electrically separated from each other. As Figure 8 shown, the common electrodes 56 are formed in a region from the lower surface (-Z side surface) of the drive wall Wd to a position closer to the +Z side than the central position of the ejection channel 51 in the Z direction. The common electrodes 56 extend, for example, up to a position closer to the +Z side than the boundary (bonding surface) between two piezoelectric substrates having different polarization directions.

[0100] A plurality of common pads 58 electrically connected to the common electrodes 56 are provided on the lower surface of the actuator plate 50. The common pads 58 electrically connect the pair of common electrodes 56 opposed to each other within the same ejection channel 51. The common pads 58 are provided around the ejection channel 51.

[0101] As Figure 6 shown, a pair of individual electrodes 57 opposed to each other within the same non-ejection channel 52 are electrically separated from each other. As Figure 9 shown, the individual electrodes 57 are formed in a region from the lower surface of the drive wall Wd to a position closer to the +Z side than the central position of the non-ejection channel 52 in the Z direction. The individual electrodes 57 extend, for example, up to a position closer to the +Z side than the boundary (bonding surface) between two piezoelectric substrates having different polarization directions.

[0102] A plurality of individual pads 59 electrically connected to the individual electrodes 57 are provided on the lower surface of the actuator plate 50. The individual pads 59 electrically connect the pair of individual electrodes 57 opposed to each other via the ejection channel 51. As Figure 7 shown, the individual pads 59 are arranged between non-ejection channels 52 adjacent to each other with the ejection channel 51 interposed therebetween. The individual pads 59 are provided so as to be electrically separated from the common pads 58. The individual pads 59 are arranged on the outer side in the Y direction than the common pads 58. The individual pads 59 are provided so as to straddle non-ejection channels 52 adjacent in the X direction.

[0103] On the lower surface of the actuator plate 50, an electrode separation portion Sp for electrically separating the common pad 58 and the individual pads 59 is provided. The electrode separation portion Sp extends linearly along the Y direction. One end of the electrode separation portion Sp in the Y direction is connected to the groove portion Di. The other end of the electrode separation portion Sp in the Y direction is connected to a portion of the lower surface of the actuator plate 50 where no electrode is formed (electrode non-formation portion 50N).

[0104] As Figure 3 shown, an external substrate 45 for electrically connecting the drive electrodes 55 and the inkjet head 5 to each other is mounted on the tail portion 50Y. For example, the external substrate 45 is a flexible printed circuit board having flexibility. However, in Figure 3 , a part of the outer edge (outline) of the external substrate 45 is shown by a dashed line. The wiring pattern formed on the external substrate 45 is electrically connected to each of the above-mentioned common pad 58 and individual pads 59 (refer to Figure 7 ). Thus, the drive voltage is applied from the inkjet head 5 to each drive electrode 55 via the external substrate 45.

[0105] As Figure 7 shown, a groove portion Di extending along the X direction is provided between the common pad 58 and the individual pad 59 on the lower surface of the actuator plate 50. The width of the groove portion Di in the Y direction is larger than the width of the connection wiring (not shown) formed on the external substrate 45 in the Y direction. Thus, when the external substrate 45 is connected to the actuator plate 50, the connection wiring of the external substrate 45 is arranged at a position corresponding to the groove portion Di of the actuator plate 50, so that it is possible to prevent the connection wiring of the external substrate 45 from coming into contact with the individual pad 59 of the actuator plate 50. Therefore, it is possible to prevent an electrical short circuit between the connection wiring of the external substrate 45 and the individual pad 59 of the actuator plate 50 and the individual electrode 57 connected to the individual pad 59.

[0106] In addition, as Figure 9 shown, it is preferable that the length (depth) of the groove portion Di in the Z direction is smaller than the length of each electrode provided on the side surface of the drive wall Wd in the Z direction. Thus, it is possible to form the groove portion Di on the side surface of the drive wall Wd without cutting off each electrode.

[0107] [Cover plate]

[0108] As Figure 3 shown, the outer shape of the cover plate 60 is a rectangular plate shape having a long side along the X direction and a short side along the Y direction. For example, the lengths of the long side and the short side of the cover plate 60 are substantially the same as the lengths of the long side and the short side of the actuator plate 50.

[0109] The cover plate 60 is a plate for introducing ink into the actuator plate 50 (the plurality of ejection channels 51) and discharging the ink from the actuator plate 50. As Figure 6As shown, the actuator plate 50 is disposed between the intermediate plate 42 and the cover plate 60. The lower surface of the cover plate 60 is joined to the upper surface of the actuator plate 50.

[0110] As Figure 3 shown, the cover plate 60 has ink flow paths Lp1, Lp2 (liquid flow paths) that communicate with the ejection channels 51. Further, the ink flow paths Lp1, Lp2 do not communicate with the non-ejection channels 52 (see Figure 9 ). The ink flow paths Lp1, Lp2 are provided in the following two sets: a first flow path Lp1 corresponding to the ejection channels 51 of the first channel column Ch1, and a second flow path Lp2 corresponding to the ejection channels 51 of the second channel column Ch2.

[0111] The ink flow paths Lp1, Lp2 extend in the X direction. Further, when there is no need to particularly distinguish, the two sets of flow paths are referred to as ink flow paths for explanation. As Figure 10 shown, the ink flow path has a manifold 60a that opens the cover plate 60 to the +Z side and a slit 60b that communicates with the manifold 60a and opens to the -Z side. The manifold 60a communicates with the ejection channels 51 through the slit 60b. Further, the manifold 60a does not communicate with the non-ejection channels 52.

[0112] As Figure 3 shown, the ink flow path has an ink supply flow path 61 that supplies ink to the ejection channels 51 and an ink discharge flow path 62 that discharges ink from the ejection channels 51. The ink supply flow paths 61 of the first flow path Lp1 and the second flow path Lp2 may also be arranged adjacent to each other in the Y direction.

[0113] As Figure 8 shown, the ink supply flow path 61 communicates with one end in the Y direction of the ejection channels 51. The ink supply flow path 61 extends in the X direction across one end in the Y direction of each ejection channel 51. Ink is supplied to each ejection channel 51 through the ink supply flow path 61.

[0114] The ink discharge flow path 62 communicates with the other end in the Y direction of the ejection channels 51. The ink discharge flow path 62 extends in the X direction across the other end in the Y direction of each ejection channel 51. Ink is discharged from each ejection channel 51 through the ink discharge flow path 62.

[0115] Further, the cover plate 60 may be formed of a material having insulation properties and a thermal conductivity equal to or higher than that of the material forming the actuator plate 50. For example, when the actuator plate 50 is formed of PZT, the cover plate 60 is preferably formed of PZT or silicon. Thereby, the temperature deviation on the actuator plate 50 can be alleviated, and the ink temperature can be made uniform. Thereby, the ejection speed of the ink can be made uniform, and the printing stability can be improved.

[0116] [Nozzle Plate]

[0117] As shown Figure 3 in Figure 3 , the outer shape of the nozzle plate 41 is a rectangular plate shape having a long side in the X direction and a short side in the Y direction. As shown Figure 6 in Figure 6 , the nozzle plate 41 is disposed opposite to the actuator plate 50 via an intermediate plate 42. As shown Figure 4 in Figure 4 , the nozzle plate 41 has a plurality of nozzle rows Nr1, Nr2 (for example, two rows in the present embodiment) arranged at a predetermined interval in the Y direction. The inkjet head 5 is a so-called two-row type inkjet head. The two nozzle rows Nr1, Nr2 are a first nozzle row Nr1 corresponding to the first channel row Ch1 and a second nozzle row Nr2 corresponding to the second channel row Ch2. In addition, when there is no need to particularly distinguish, the two nozzle rows are referred to as nozzle rows for description.

[0118] The nozzle rows extend in the X direction. The nozzle rows have a plurality of nozzle holes 41a arranged at a predetermined interval in the X direction. The nozzle holes 41a are ejection ports for ink. The nozzle holes 41a penetrate the nozzle plate 41 in the Z direction. The opening shape of the nozzle holes 41a (the shape of the nozzle holes 41a observed from the Z direction) is, for example, circular.

[0119] As shown Figure 6 in Figure 6 , the direction in which ink is ejected from the nozzle holes 41a (the ink ejection direction) is the -Z side. In other words, the ink ejection direction is from the actuator plate 50 toward the nozzle plate 41. The inner diameter of the nozzle holes 41a gradually decreases toward the ink ejection direction. That is, the nozzle holes 41a are tapered through holes whose diameter decreases toward the -Z side.

[0120] The nozzle holes 41a communicate with the ejection channels 51 via communication holes 42a. Thus, the ink supplied from each ejection channel 51 is ejected from each nozzle hole 41a.

[0121] On the other hand, the nozzle holes 41a do not communicate with the non-ejection channels 52. The non-ejection channels 52 are covered by the nozzle plate 41 from below.

[0122] As shown[[ID=2%]] Figure 5 in Figure 5 , the nozzle holes 41a are disposed at positions corresponding to substantially the central region in the Y direction of the ejection channels 51. The pitch of the plurality of nozzle holes 41a in the X direction (the distance between two adjacent nozzle holes 41a) is substantially the same as the pitch of the plurality of ejection channels 51 in the X direction (the distance between two adjacent ejection channels 51). As shown Figure 4 in Figure 4 , the nozzle holes 41a of the first nozzle row Nr1 and the nozzle holes 41a of the second nozzle row Nr2 are arranged differently from each other in the X direction. That is, the nozzle holes 41a of each nozzle row Nr1, Nr2 are arranged in a staggered manner in the X direction.

[0123] In addition, the nozzle plate 41 can also be formed of a conductive material. The type of the conductive material is not particularly limited, and a metal material such as stainless steel (SUS) is preferably used. Since the metal material has high frictional properties (rubbing properties), the nozzle plate 41 includes the metal material, thereby improving the physical strength of the nozzle plate 41. In addition, the type of SUS is not particularly limited, and examples thereof include SUS316L and SUS304.

[0124] [Intermediate plate]

[0125] As Figure 6 shown, the head chip 40 further includes an intermediate plate 42. The outer shape of the intermediate plate 42 is a rectangular plate shape having a long side in the X direction and a short side in the Y direction. For example, the outer shape of the intermediate plate 42 is substantially the same as the outer shape of the nozzle plate 41. The intermediate plate 42 is disposed between the nozzle plate 41 and the actuator plate 50. The intermediate plate 42 is a plate for aligning the nozzle plate 41 and the actuator plate 50 with each other.

[0126] The intermediate plate 42 has a plurality of communication holes 42a at positions corresponding to each of the plurality of ejection channels 51 and the plurality of nozzle holes 41a. Each communication hole 42a is arranged in the same manner as each ejection channel 51. As Figure 5 shown, each communication hole 42a extends in the Y direction and is arranged at a predetermined interval in the X direction. In addition, when viewed from the Z direction, the communication holes 42a are not provided at positions overlapping the non-ejection channels 52.

[0127] The width of the communication hole 42a in the X direction is preferably larger than the width of the ejection channel 51 in the X direction. Thereby, it is difficult for the actuator plate 50 to obstruct the flow of the ink supplied from the ejection channel 51 to the nozzle hole 41a. Therefore, it is difficult to cause defects related to the ink ejection characteristics such as deflection of the ink ejection direction. In addition, more preferably, when viewed from the Z direction, the ejection channel 51 can be arranged in the area defined by the width of the communication hole 42a.

[0128] As Figure 11 shown, the intermediate plate 42 has a stepped portion 43 at a portion that divides the nozzle peripheral region Ra and the connection region Rc. In Figure 12 the sectional view, the stepped portion 43 is formed in an L shape. The stepped portion 43 has a first wall surface 43a parallel to the XY plane and a second wall surface 43b parallel to the XZ plane. The first wall surface 43a is disposed between the upper surface and the lower surface of the intermediate plate 42. The second wall surface 43b is disposed between the -Y side end of the first wall surface 43a and the +Y side end of the lower surface of the intermediate plate 42.

[0129] The intermediate plate 42 is preferably formed of an insulating material. The type of the insulating material is not particularly limited, and examples thereof include glass, polyimide, polypropylene, polyethylene terephthalate, etc. For example, in the case where the substrate of the intermediate plate 42 is formed of the above materials, the structure may also be such that the periphery of the substrate is covered with parylene or the like.

[0130] In addition, examples of the material of the intermediate plate 42 include alumina and the like. Furthermore, the intermediate plate 42 is not limited to the above materials, and may also be formed of a piezoelectric material such as PZT in the same manner as the actuator plate 50.

[0131] As Figure 6 shown, the nozzle plate 41 and the actuator plate 50 are bonded to each other via the intermediate plate 42. Thereby, the conductive nozzle plate 41 and the conductive actuator plate 50 are electrically separated (insulated) via the insulating intermediate plate 42. If the nozzle plate 41 and the actuator plate 50 are insulated via the intermediate plate 42, a conductive material can be used as the forming material of the nozzle plate 41, and a piezoelectric material can be used as the forming material of the actuator plate 50. Therefore, a metal material having high friction performance or the like can be used as the forming material of the nozzle plate 41. Thereby, a short circuit between the nozzle plate 41 and the actuator plate 50 is suppressed, and at the same time, it is difficult for the nozzle plate 41 to be damaged (such as worn).

[0132] For example, the intermediate plate 42 preferably has a linear expansion coefficient E1 (E2 < E1 < E3 or E3 < E1 < E2) between the linear expansion coefficient E2 of the nozzle plate 41 and the linear expansion coefficient E3 of the actuator plate 50. By satisfying the above relationship, when each of the nozzle plate 41, the intermediate plate 42, and the actuator plate 50 undergoes thermal deformation, the displacement of each of the nozzle plate 41 and the actuator plate 50 due to the difference in the linear expansion coefficient (thermal expansion coefficient) is absorbed by the intermediate plate 42. Therefore, compared with the case where the intermediate plate 42 is not interposed between the nozzle plate 41 and the actuator plate 50, peeling of the nozzle plate 41 and the actuator plate 50 due to thermal deformation can be suppressed. Thus, it is difficult to cause defects such as deflection when ejecting ink.

[0133] [Operation of the printer]

[0134] As Figure 1 shown, in the printer 1 of the present embodiment, the recording paper P is conveyed in the X direction, and the carriage 33 reciprocates in the Y direction. The inkjet head 5 on the carriage 33 ejects ink onto the recording paper P while reciprocating in the Y direction. Thereby, an image or the like is recorded on the recording paper P.

[0135] [Operation of the inkjet head]

[0136] In the inkjet head 5 of the present embodiment, ink is ejected onto the recording paper P using the shear (cutting) mode in the following order.

[0137] Initially, if the carriage 33 reciprocates, a drive voltage is applied to the drive electrodes 55 (common electrode 56 and individual electrodes 57) via the external substrate 45. Specifically, the drive voltage is applied to each drive electrode 55 provided on a pair of drive walls Wd that define the ejection channels 51. As a result, each of the pair of drive walls Wd deforms to protrude toward the non-ejection channel 52 adjacent to the ejection channel 51.

[0138] Here, as described above, two piezoelectric substrates with polarization directions set to different directions in the Z direction are laminated in the actuator plate 50. Further, the drive electrode 55 extends from the lower surface of the drive wall Wd to a region on the +Z side beyond the central position of the drive wall Wd in the Z direction. In this case, when a drive voltage is applied to the drive electrode 55, based on the piezoelectric thickness shear effect, the drive wall Wd bends and deforms starting from approximately the central position of the drive wall Wd in the Z direction. As a result, each ejection channel 51 deforms as if it expands by using the bending deformation of the drive wall Wd described above.

[0139] By using the bending deformation of the pair of drive walls Wd based on this piezoelectric thickness shear effect, the volume of each ejection channel 51 increases. As a result, the ink supplied to each ink supply flow path 61 is guided into the interior of each ejection channel 51.

[0140] Next, the ink guided into the interior of each ejection channel 51 propagates as a pressure wave inside each ejection channel 51. In this case, when the pressure wave reaches the nozzle holes 41a provided in the nozzle plate 41, the drive voltage applied to the drive electrodes 55 becomes zero (0 V). As a result, the bent and deformed drive wall Wd returns to its original state, and thus the volume of each ejection channel 51 returns to its original state.

[0141] Finally, when the volume of each ejection channel 51 returns to its original state, the pressure increases inside each ejection channel 51, and thus the ink guided into the interior of each ejection channel 51 is pressurized. As a result, droplet-shaped ink is ejected from each nozzle hole 41a to the outside (recording paper P).

[0142] In this case, for example, as described above, the inner diameter of the nozzle hole 41a gradually decreases in the ink ejection direction, so the ejection speed of the ink increases and the linear advance of the ink improves. As a result, the quality of an image or the like recorded on the recording paper P is improved.

[0143] [Manufacturing method of an inkjet head]

[0144] Figure 13 It is a flowchart of a manufacturing method of an inkjet head.

[0145] As Figure 13As shown, the manufacturing method of the inkjet head 5 of the present embodiment includes a substrate preparation process, a cover plate bonding process, a channel formation process, an electrode formation process, an electrode separation process, a groove portion formation process, a mask arrangement process, a protective film formation process, a mask removal process for the connection region, a nozzle plate bonding process, and an external substrate connection process.

[0146] In the substrate preparation process ( Figure 13 step S1), a wafer or the like for obtaining the components of the inkjet head 5 is prepared in advance. Hereinafter, the substrate (for example, a wafer) for obtaining the actuator plate 50 is referred to as the actuator plate substrate AW. In the substrate preparation process, a groove including a plurality of channels is formed in the actuator plate substrate AW. In the substrate preparation process, a cover plate 60 having an ink flow path is prepared (refer to Figure 3 ). In the substrate preparation process, a stepped portion 43 is formed at a position in the intermediate plate 42 that divides the nozzle peripheral region Ra and the connection region Rc (refer to Figure 11 ). After the substrate preparation process, it proceeds to the cover plate bonding process ( Figure 13 step S2).

[0147] In the cover plate bonding process, the cover plate 60 is bonded to the upper surface of the actuator plate substrate AW. Thus, a bonded wafer in which the actuator plate substrate AW and the cover plate 60 are bonded is obtained. After the cover plate bonding process, it proceeds to the channel formation process ( Figure 13 step S3).

[0148] In the channel formation process, for example, the lower surface of the actuator plate substrate AW is ground by a grinder. Thus, the channels 51, 52 (refer to Figure 7 ) are opened on the lower surface of the actuator plate substrate AW. In addition, the lower surface (the first surface) of the actuator plate substrate AW is the surface on the side where the nozzle plate 41 is arranged (refer to Figure 8 ). After the channel formation process, it proceeds to the electrode formation process ( Figure 13 step S4).

[0149] In the electrode formation process, for example, a conductive film is formed on the inner surfaces of the channels 51, 52 and the lower surface of the actuator plate substrate AW by an oblique evaporation method. After the electrode formation process, it proceeds to the electrode separation process ( Figure 13 step S5).

[0150] In the electrode separation process, for example, by laser patterning, the conductive film is separated into a common pad 58 and individual pads 59 on the lower surface of the actuator plate substrate AW (refer to Figure 7 ). After the electrode separation process, it proceeds to the groove portion formation process ( Figure 13 step S6).

[0151] In the groove forming process, for example, a groove portion Di extending in the X direction is formed by a cutting machine (refer to Figure 7 ). After the groove forming process, it moves to the mask placement process ( Figure 13 , step S7).

[0152] As Figure 14 shown, in the mask placement process, a mask (intermediate plate 42 and connection area mask Ma) having an opening (communication hole 42a) exposing the injection channel 51 is placed on the lower surface of the actuator plate substrate AW.

[0153] Specifically, in the mask placement process, first, the intermediate plate 42 is joined to the nozzle peripheral area Ra on the lower surface of the actuator plate substrate AW. In the mask placement process, after joining the intermediate plate 42 to the nozzle peripheral area Ra, the connection area mask Ma is placed on the connection area Rc on the lower surface of the actuator plate substrate AW. For example, as the connection area mask Ma, a masking member such as a tape is used. In the mask placement process, the connection area mask Ma is placed on the tail portion 50Y on the lower surface of the actuator plate substrate AW (refer to Figure 7 ). When placing the connection area mask Ma, the -Y edge of the connection area mask Ma is aligned with the step portion 43 (e.g., the second wall surface 43b) of the intermediate plate 42.

[0154] In the mask placement process, the connection area mask Ma is placed across the lower surface of the actuator plate substrate AW and the two side surfaces of the actuator plate substrate AW in the X direction. In addition, the side surface (second surface) of the actuator plate substrate AW in the X direction is a surface orthogonal (crossing) to the lower surface of the actuator plate substrate AW.

[0155] For example, as Figure 15 shown, in the mask placement process, the connection area mask Ma extends from the X-side end on the lower surface of the actuator plate substrate AW to a position on the +Z side beyond the joint surface between the actuator plate substrate AW and the cover plate 60. In addition, in the mask placement process, the connection area mask Ma can also be placed across the lower surface of the actuator plate substrate AW and the side surface of the actuator plate substrate AW in the Y direction.

[0156] As Figure 14 shown, through the mask placement process, the injection channel 51 is exposed from the communication hole 42a (opening) of the intermediate plate 42 and the non-injection channel 52 is covered by the intermediate plate 42 and the connection area mask Ma. After the mask placement process, it moves to the protective film forming process ( Figure 13 , step S8).

[0157] In the protective film forming process, a protective film 70 is formed in a state where the ejection passage 51 is exposed and the non-ejection passage 52 is covered (see Figure 8 ). The protective film 70 protects the common electrode 56 formed on the inner surface of the ejection passage 51 (see Figure 8 ) from the influence of ink. In the protective film forming process, with the intermediate plate 42 disposed in the nozzle peripheral region Ra and the connection region Rc covered with the connection region mask Ma, a protective film is formed in the ejection passage 51 through the communication hole 42a of the intermediate plate 42.

[0158] In the protective film forming process, a fluid for forming the protective film in the ejection passage 51 is supplied to the ejection passage 51 through the communication hole 42a of the intermediate plate 42 and the ink flow paths Lp1, Lp2 of the cover plate 60 (see Figure 10 ). For example, p-xylene dimers are heated to form monomer vapor, and the monomers react on the inner surface of the ejection passage 51 as the object to form a protective film. After the protective film forming process, the process moves to the connection region mask removing process ( Figure 13 step S9).

[0159] In the connection region mask removing process, the connection region mask Ma is removed from the lower surface of the actuator plate substrate AW. After the connection region mask removing process, the process moves to the nozzle plate bonding process ( Figure 13 step S10).

[0160] In the nozzle plate bonding process, the nozzle plate 41 is bonded to the lower surface of the intermediate plate 42 (see Figure 8 ). When the nozzle plate 41 is disposed, the +Y edge of the nozzle plate 41 (see Figure 16 ) is aligned with the step portion 43 (e.g., the second wall surface 43b) of the intermediate plate 42. After the nozzle plate bonding process, the process moves to the external substrate connection process ( Figure 13 step S11).

[0161] In the external substrate connection process, the external substrate 45 (see Figure 3 ) is connected to the connection region Rc on the lower surface of the actuator plate 50 (see Figure 7 ).

[0162] Through the above steps, the inkjet head 5 of the present embodiment is completed (see Figure 8 ).

[0163] In addition, the manufacturing method of the inkjet head is not limited to the above examples, and various methods can be adopted.

[0164] For example, the manufacturing method of the inkjet head can also be carried out in the following order.

[0165] First, each of the channels 51 and 52 is formed in the substrate AW for the actuator plate. Next, electrodes are formed on the inner surfaces of the channels 51 and 52. Next, the substrate for the cover plate is bonded to the substrate AW for the actuator plate to form a bonding wafer. Next, the bonding wafer is singulated (dicing the chips). Next, a protective film is formed at required portions on the singulated wafer. Next, the nozzle plate 41 is bonded to the wafer on which the protective film has been formed.

[0166] For example, the manufacturing method of an inkjet head may also be performed in the following order.

[0167] First, each of the channels 51 and 52 is formed in the substrate AW for the actuator plate. Next, electrodes are formed on the inner surfaces of the channels 51 and 52 from the upper surface side of the substrate AW for the actuator plate. Next, the substrate for the cover plate is bonded to the substrate AW for the actuator plate to form a bonding wafer. Next, the lower surface of the bonding wafer (the lower surface of the substrate AW for the actuator plate) is ground. Thereby, each of the channels 51 and 52 is opened on the lower surface of the substrate AW for the actuator plate. Next, electrodes are formed on the inner surfaces of the channels 51 and 52 from the lower surface side of the substrate AW for the actuator plate. Next, a protective film is formed at required portions. Next, the nozzle plate 41 is bonded to the wafer on which the protective film has been formed.

[0168] In addition, the forming direction of the electrodes with respect to the substrate AW for the actuator plate may be either a direction from the upper surface side of the substrate AW for the actuator plate toward the lower surface side or a direction from the lower surface side of the substrate AW for the actuator plate toward the upper surface side.

[0169] As described above, the manufacturing method of the head chip 40 according to the embodiment includes: a substrate preparation step of preparing the substrate AW for the actuator plate having the ejection channels 51 communicating with the nozzle holes 41a for ejecting ink and the non-ejection channels 52 not ejecting ink; and a protective film forming step of forming, after the substrate preparation step, a protective film 70 that protects the common electrode 56 formed on the inner surface of the ejection channel 51 from the influence of the ink in a state where the ejection channel 51 is exposed and the non-ejection channel 52 is covered.

[0170] According to this method, the protective film 70 is formed on the exposed ejection channel 51 in a state where the non-ejection channel 52 is covered, so that the formation of the protective film 70 on the non-ejection channel 52 can be suppressed. The non-ejection channel 52 is a portion where the protective film 70 is not required, and thus the man-hours for removing the protective film 70 at unnecessary portions can be reduced.

[0171] For example, as a comparative example, an example is given as Figure 17As shown, in a state where only the connection region Rc is covered with a masking member Ma such as a tape and the ejection channels 51 and non-ejection channels 52 in the nozzle peripheral region Ra are exposed, a protective film 70 (e.g., a parylene film) is formed on the exposed ejection channels 51. Since the parylene film has the advantage of adhering to complex structures, the protective film 70 may sometimes also be formed on the non-ejection channels 52. For example, as a comparative example, it is exemplified as Figure 18 shown, the protective film 70 is also formed on the non-ejection channels 52 in the connection region Rc. The protective film 70 is formed across the inner surface of the non-ejection channels 52 in the connection region Rc and the inner surface of the masking member Ma. For example, in the comparative example, after the protective film 70 is formed, the masking member is removed physically (e.g., peeled off). Thus, as Figure 19 shown, when the masking member Ma is removed, the protective film 70 may be broken and fuzzing may occur.

[0172] In contrast, according to the manufacturing method of the head chip 40 according to the embodiment, as Figure 14 shown, the protective film 70 is formed on the exposed ejection channels 51 in a state where the non-ejection channels 52 are covered, so that as Figure 20 shown, it is possible to suppress the formation of the protective film 70 on the non-ejection channels 52 in the connection region Rc. Therefore, as Figure 21 shown, it is possible to suppress fuzzing of the protective film 70 when the masking member Ma is removed.

[0173] The actuator plate substrate AW of the embodiment has a lower surface on which the nozzle plate 41 is disposed, and the nozzle plate 41 has nozzle holes 41a communicating with the ejection channels 51. In the protective film forming step, after a mask (intermediate plate 42 and connection region mask Ma) having an opening (communication hole 42a) for exposing the ejection channels 51 is disposed on the lower surface of the actuator plate substrate AW, the protective film 70 is formed on the ejection channels 51 through the communication hole 42a.

[0174] According to this method, it is possible to suppress the formation of the protective film 70 on the non-ejection channels 52 by a simple method using a mask (intermediate plate 42 and connection region mask Ma).

[0175] The actuator plate substrate AW of the embodiment has a side surface intersecting the lower surface of the actuator plate substrate AW. In the protective film forming step, after a mask (connection region mask Ma) is disposed across the lower surface and the side surface of the actuator plate substrate AW, the protective film 70 is formed on the ejection channels 51 through the communication hole 42a.

[0176] When the mask is only disposed on the lower surface of the substrate AW for the actuator board, the protective film 70 may be formed at an unnecessary portion through the gap between the mask and the lower surface of the substrate AW for the actuator board. In contrast, according to the method for manufacturing the head chip 40 according to the embodiment, the mask Ma for the connection region is disposed across the lower surface and the side surface of the substrate AW for the actuator board, so as to cover the aforementioned gap by using the mask Ma for the connection region, thereby being able to suppress the formation of the protective film 70 at an unnecessary portion.

[0177] In the protective film forming step of the embodiment, after the intermediate plate 42 having the communication hole 42a communicating with the ejection channel 51 is bonded to the lower surface of the substrate AW for the actuator board as a mask, the protective film 70 is formed in the ejection channel 51 through the communication hole 42a.

[0178] According to this method, the intermediate plate 42 is a component of the head chip 40, and the intermediate plate 42 can be left as it is after the protective film forming step, so that the formation of the protective film 70 in the non-ejection channel 52 can be suppressed by a simpler method.

[0179] The lower surface of the substrate AW for the actuator board in the embodiment has a nozzle peripheral region Ra around the nozzle hole 41a and a connection region Rc for connecting the external substrate 45. In the protective film forming step, in a state where the intermediate plate 42 is disposed in the nozzle peripheral region Ra and the connection region Rc is covered by the mask Ma for the connection region, the protective film 70 is formed in the ejection channel 51 through the communication hole 42a.

[0180] According to this method, the connection region Rc suppresses the formation of the protective film 70, so that the connection failure of the external substrate 45 can be suppressed.

[0181] Before the protective film forming step of the embodiment, the stepped portion 43 is formed at a portion of the intermediate plate 42 that divides the nozzle peripheral region Ra and the connection region Rc.

[0182] According to this method, the alignment of the mask Ma for the connection region can be performed by the stepped portion 43. Further, even if fuzzing of the protective film 70 occurs when the mask Ma for the connection region is removed, the influence of the fuzzing on the nozzle peripheral region Ra can be suppressed. Further, when manufacturing the inkjet head 5, the alignment of the nozzle plate 41 can be performed by the stepped portion 43.

[0183] The head chip 40 of the embodiment includes an actuator board 50. The actuator board 50 has an ejection channel 51 communicating with the nozzle hole 41a for ejecting ink and a non-ejection channel 52 that does not eject ink. The actuator board 50 has a protective film 70 that protects the common electrode 56 formed on the inner surface of the ejection channel 51 from the influence of ink. The protective film 70 is not formed in the non-ejection channel 52.

[0184] According to this configuration, the non-injection channel 52 is a portion that does not require the protective film 70, so the man-hour for removing the protective film 70 of the unnecessary portion is not spent. Furthermore, the problem of the protective film 70 fraying does not occur either.

[0185] The actuator plate 50 of the embodiment has a nozzle peripheral region Ra around the nozzle hole 41a and a connection region Rc for connecting to the external substrate 45. The protective film 70 is not formed in the connection region Rc.

[0186] According to this configuration, poor connection of the external substrate 45 can be suppressed.

[0187] The head chip 40 of the embodiment includes an intermediate plate 42 that is joined to the actuator plate 50 and has a communication hole 42a communicating with the injection channel 51. The intermediate plate 42 has a stepped portion 43 at a position dividing the nozzle peripheral region Ra and the connection region Rc.

[0188] According to this configuration, when manufacturing the inkjet head 5, the alignment of the nozzle plate 41 can be performed by the stepped portion 43.

[0189] The inkjet head 5 and the printer 1 of the embodiment include the above head chip 40, so an inkjet head 5 and a printer 1 that can reduce the man-hour for removing the protective film of the unnecessary portion can be provided.

[0190] In addition, the technical scope of the present disclosure is not limited to the above embodiment, and various changes can be made without departing from the gist of the present disclosure.

[0191] For example, in the above embodiment, the inkjet printer 1 is exemplified as an example of the liquid jet recording device, but it is not limited to a printer. For example, the liquid jet recording device may also be a facsimile machine or a digital press, etc.

[0192] In the above embodiment, the case where the recording medium P is paper is described, but it is not limited to this configuration. The recording medium P is not limited to paper, and may also be a metal material or a resin material, or may be food, etc.

[0193] In the above embodiment, the configuration in which the liquid jet head is mounted on the liquid jet recording device is described, but it is not limited to this configuration. That is, the liquid ejected from the liquid jet head is not limited to the liquid that falls on the recording medium, and may also be, for example, a liquid medicine mixed into a preparation, or a food additive such as a seasoning or a flavor added to food, or an aromatic agent ejected into the air.

[0194] In the above embodiment, the side injection type head chip 40 is exemplified, but it is not limited thereto. For example, the present disclosure can also be applied to a so-called edge shoot type head chip that ejects ink from the front end portion in the channel extension direction of the injection channel.

[0195] In addition, the present disclosure can also be applied to a so-called roof shoot type head chip in which the direction of the pressure applied to the ink is the same as the ink ejection direction.

[0196] In the above-described embodiment, a configuration in which the Z direction coincides with the direction of gravity has been described, but the present invention is not limited to this configuration. For example, the Z direction can also be along the horizontal direction.

[0197] In the above-described embodiment, the two-row type inkjet head 5 in which the nozzle holes 41a are arranged in two rows has been described, but the present invention is not limited to this. For example, the inkjet head can also have three or more rows of nozzle holes 41a, or can also be an inkjet head having a single row of nozzle holes 41a.

[0198] In the above-described embodiment, a configuration in which the ejection channels 51 and the non-ejection channels 52 are alternately arranged has been described, but the present invention is not limited to this. For example, the present disclosure can also be applied to an inkjet head of a so-called three-cycle method in which ink is ejected sequentially from all channels.

[0199] In the above-described embodiment, a configuration in which a chevron type is used as the actuator plate 50 has been described, but the present invention is not limited to this. That is, a unipolar type (polarization direction is in one direction in the thickness direction) actuator plate can also be used.

[0200] In the above-described embodiment, a configuration in which the actuator plate 50 includes a connection region Rc for connecting to the external substrate 45 has been described, but the present invention is not limited to this. For example, the actuator plate 50 may not include the connection region Rc. For example, the connection region Rc may also be provided on a substrate other than the actuator plate 50 such as the cover plate 60.

[0201] In the above-described embodiment, a configuration in which the head chip 40 includes a cover plate 60 that is joined to the actuator plate 50 and has ink flow paths Lp1 and Lp2 communicating with the ejection channels 51 has been described, but the present invention is not limited to this. For example, the head chip 40 may not include the cover plate 60. For example, the head chip 40 may also include a flow path plate that is joined to the actuator plate 50 and has a flow path communicating with the ejection channels 51.

[0202] In the above-described embodiment, an example has been given in which in the protective film forming process, after the intermediate plate 42 having the communication holes 42a for exposing the ejection channels 51 and the connection region are arranged on the lower surface of the actuator plate substrate AW using the mask Ma, the protective film 70 is formed on the ejection channels 51 through the communication holes 42a, but the present invention is not limited to this. For example, in the protective film forming process, after a mask having an opening for exposing the ejection channels 51 is arranged on the lower surface of the actuator plate substrate AW, the protective film 70 can be formed on the ejection channels 51 through the opening.

[0203] In the above-described embodiment, as an example, in the protective film forming step, after disposing the mask Ma for the connection region across the lower surface and the side surface of the actuator plate substrate AW, the protective film 70 is formed in the ejection channel 51 through the communication hole 42a. However, the present invention is not limited thereto. For example, in the protective film forming step, a mask having an opening may be disposed only on the lower surface of the actuator plate substrate AW, and then the protective film may be formed in the ejection channel 51 through the opening.

[0204] In the above-described embodiment, as an example, in the protective film forming step, after joining the intermediate plate 42 having the communication hole 42a communicating with the ejection channel 51 to the lower surface of the actuator plate substrate AW as a mask, the protective film 70 is formed in the ejection channel 51 through the communication hole 42a. However, the present invention is not limited thereto. For example, in the protective film forming step, a mask other than the intermediate plate 42 may be disposed on the lower surface of the actuator plate substrate AW, and then the protective film 70 may be formed in the ejection channel 51 through the opening of the mask.

[0205] In the above-described embodiment, as an example, in the protective film forming step, with the intermediate plate 42 disposed in the nozzle peripheral region Ra and the connection region Rc covered by the mask Ma for the connection region, the protective film 70 is formed in the ejection channel 51 through the communication hole 42a. However, the present invention is not limited thereto. For example, in the protective film forming step, with the intermediate plate 42 disposed in the nozzle peripheral region Ra and the connection region Rc exposed, the protective film may be formed in the ejection channel 51 through the communication hole 42a.

[0206] In the above-described embodiment, as an example, the stepped portion 43 is formed in the intermediate plate 42 at a position dividing the nozzle peripheral region Ra and the connection region Rc before the protective film forming step. However, the present invention is not limited thereto. For example, the stepped portion 43 may not be formed in the intermediate plate 42 before the protective film forming step.

[0207] In the above-described embodiment, as an example, the protective film 70 satisfies the following (A). However, the present invention is not limited thereto. For example, the protective film 70 may also satisfy the following (B).

[0208] (A) The protective film 70 is not formed in the non-ejection channel 52.

[0209] (B) The protective film 70 is also formed in the non-ejection channel 52, and the thickness T2 of the protective film 70 in the non-ejection channel 52 is smaller than the thickness T1 of the protective film 70 in the ejection channel 51 (T2 < T1).

[0210] According to this configuration, the non-ejection channel 52 is a portion where the protective film 70 is not required, so that the man-hours for removing the protective film 70 from the unnecessary portion can be reduced. Furthermore, as described above, the occurrence of fuzz on the protective film 70 can be suppressed.

[0211] For example, the head chip 40 may also include an actuator plate 50 having a protective film 70 that satisfies both of the above (A) and (B).

[0212] In the above-described embodiment, it is exemplified that the protective film 70 is not formed in the connection region Rc, but it is not limited thereto. For example, the protective film 70 may also be formed in the connection region Rc.

[0213] In the above-described embodiment, it is exemplified that the head chip 40 includes an intermediate plate 42 that is joined to the actuator plate 50 and has a communication hole 42a communicating with the ejection channel 51, but it is not limited thereto. For example, the head chip 40 may not include the intermediate plate 42.

[0214] In the above-described embodiment, it is exemplified that the intermediate plate 42 has a stepped portion 43 at a position dividing the nozzle peripheral region Ra and the connection region Rc, but it is not limited thereto. For example, the intermediate plate 42 may not have the stepped portion 43.

[0215] In the following modification examples, the same reference numerals are given to the same configurations as those in the above-described embodiment, and the detailed description thereof is omitted.

[0216] Figure 22 It is a cross-sectional view of the stepped portion of the intermediate plate 142 according to a modification example of the embodiment. Figure 22 It is related to Figure 12 The corresponding cross-sectional view.

[0217] In the above-described embodiment, it is exemplified that the stepped portion 43 has a first wall surface 43a parallel to the XY plane and a second wall surface 43b parallel to the XZ plane (see Figure 12 ), but it is not limited thereto. For example, as Figure 22 shown, the stepped portion 143 may also have a first wall surface 143a parallel to the XY plane, a second wall surface 143b parallel to the XZ plane, and a third wall surface 143c. That is, the stepped portion 143 may be formed in a U shape that opens toward the -Z side in the cross-sectional view of Figure 22 . For example, the stepped portion 143 may also divide and form a groove extending in the X direction on the lower surface of the intermediate plate 142.

[0218] In addition, within the scope not departing from the gist of the present disclosure, the constituent elements in the above-described embodiment can be replaced with well-known constituent elements. Also, the above-described modification examples can be combined with each other.

[0219] [Reference Signs]

[0220] 1 Inkjet printer (liquid ejection recording device); 5, 5K, 5C, 5M, 5Y inkjet heads (liquid ejection heads); 40 head chips (liquid ejection head chips); 41 nozzle plates; 41a nozzle holes; 42, 142 intermediate plates; 42a communication holes; 43, 143 stepped portions; 45 external substrates; 50 actuator plates; 51 ejection channels; 52 non-ejection channels; 56 common electrodes (electrodes); 70 protective films; AW substrates for actuator plates; Ma masks for connection regions (masks); Ra nozzle peripheral regions; Rc connection regions.

Claims

1. A manufacturing method of a liquid ejection head chip, comprising: A substrate preparation step of preparing a substrate for an actuator plate having an ejection channel communicating with a nozzle hole for ejecting a liquid and a non-ejection channel for not ejecting the liquid; And A protective film formation step of, after the substrate preparation step, forming a protective film for protecting an electrode formed on an inner surface of the ejection channel from the influence of the liquid in a state where the ejection channel is exposed and the non-ejection channel is covered. The substrate for the actuator plate has a first surface on which a nozzle plate is disposed, and the nozzle plate has the nozzle hole communicating with the ejection channel, The first surface of the substrate for the actuator plate has a nozzle peripheral region around the nozzle hole and a connection region for connecting to an external substrate, In the protective film formation step, a middle plate having a communication hole communicating with the ejection channel is disposed as a mask having an opening for exposing the ejection channel in the nozzle peripheral region, and the connection region is covered by a connection region mask as the mask, and the protective film is formed in the ejection channel through the communication hole.

2. The manufacturing method of the liquid ejection head chip according to claim 1, wherein In the protective film formation step, after the mask having an opening for exposing the ejection channel is disposed on the first surface of the substrate for the actuator plate, the protective film is formed in the ejection channel through the opening.

3. The manufacturing method of the liquid ejection head chip according to claim 2, wherein The substrate for the actuator plate further has a second surface intersecting with the first surface, In the protective film formation step, after the mask is disposed across the first surface and the second surface of the substrate for the actuator plate, the protective film is formed in the ejection channel through the opening.

4. The manufacturing method of the liquid ejection head chip according to claim 2 or 3, wherein In the protective film formation step, after the middle plate is bonded to the first surface of the substrate for the actuator plate, the protective film is formed in the ejection channel through the communication hole.

5. The manufacturing method of the liquid ejection head chip according to claim 1, wherein Before the protective film formation step, a stepped portion is formed at a position in the middle plate that divides the nozzle peripheral region and the connection region.

6. A liquid ejection head chip including an actuator plate having an ejection channel communicating with a nozzle hole for ejecting a liquid and a non-ejection channel for not ejecting the liquid, The actuator plate has a protective film for protecting an electrode formed on an inner surface of the ejection channel from the influence of the liquid, and the protective film satisfies the following (A): (A) The protective film is not formed in the non-ejection channel, The actuator plate has a nozzle peripheral region around the nozzle hole and a connection region for connecting to an external substrate, The protective film is not formed in the connection region.

7. The liquid ejection head chip according to claim 6, wherein It further includes an intermediate plate that is joined to the actuator plate and has communication holes communicating with the ejection channels. The intermediate plate has a stepped portion at a position dividing the nozzle peripheral region and the connection region.

8. A liquid ejection head including the liquid ejection head chip according to claim 6 or 7.

9. A liquid ejection recording apparatus including the liquid ejection head according to claim 8.

10. A method for manufacturing a liquid ejection head chip, comprising: a substrate preparation step of preparing a substrate for an actuator plate having ejection channels communicating with nozzle holes for ejecting liquid and non-ejection channels that do not eject the liquid; and a protective film formation step of, after the substrate preparation step, forming a protective film for protecting an electrode formed on an inner surface of the ejection channel from the influence of the liquid in a state where the ejection channels are exposed and the non-ejection channels are covered. The substrate for the actuator plate has a first surface on which a nozzle plate is disposed, and the nozzle plate has the nozzle holes communicating with the ejection channels. In the protective film formation step, after disposing a mask having an opening for exposing the ejection channels on the first surface of the substrate for the actuator plate, the protective film is formed in the ejection channels through the opening. The substrate for the actuator plate further has a second surface intersecting the first surface. In the protective film formation step, after disposing the mask across the first surface and the second surface of the substrate for the actuator plate, the protective film is formed in the ejection channels through the opening.

11. The method for manufacturing a liquid ejection head chip according to claim 10, wherein in the protective film formation step, after joining an intermediate plate having communication holes communicating with the ejection channels as the mask to the first surface of the substrate for the actuator plate, the protective film is formed in the ejection channels through the communication holes.

12. The method for manufacturing a liquid ejection head chip according to claim 11, wherein the first surface of the substrate for the actuator plate has a nozzle peripheral region around the nozzle holes and a connection region for connecting to an external substrate. In the protective film formation step, in a state where the intermediate plate as the mask is disposed in the nozzle peripheral region and the connection region is covered by a mask for the connection region as the mask, the protective film is formed in the ejection channels through the communication holes.

13. The method for manufacturing a liquid ejection head chip according to claim 12, wherein before the protective film formation step, a stepped portion is formed at a position in the intermediate plate that divides the nozzle peripheral region and the connection region.

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