JP2016140992A - Inkjet head and printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inkjet head capable of preventing the reduction of the rigidity of a nozzle plate while taking account of manufacturing processes.SOLUTION: An inkjet head comprises: a plurality of pressure chamber walls 50a each applying a pressure to a pressure chamber S; and a nozzle plate 40 adhering to an end surface of each pressure chamber wall. The plurality of pressure chamber walls is disposed in a line such that wall surfaces face one another. The nozzle plate comprises: a resin film 41 in which a plurality of nozzle holes 43 is provided; and a metal film 42 which is disposed on a surface of the resin film and which has an opening in a region where the nozzle holes are disposed. The nozzle plate adheres to the end surface of each pressure chamber wall in such a manner that the nozzle holes are placed between the pressure chamber walls.SELECTED DRAWING: Figure 6

Description

  Embodiments described herein relate generally to an inkjet head and a printer.

  2. Related Art Ink jet heads that discharge ink from nozzle holes by deforming pressure chambers provided in the ink circulation path are known. This type of ink jet head includes a pressure chamber wall (actuator) formed of a piezoelectric element, and a nozzle plate bonded to the pressure chamber wall.

  In many cases, the nozzle plate is made of a resin film. However, since the resin film has low rigidity, ink ejection tends to be unstable.

  The nozzle plate may be made of metal to increase the rigidity of the nozzle plate. However, in this case, it is difficult to form nozzle holes in the nozzle plate after the nozzle plate is bonded to the actuator. When the entire nozzle plate is made of metal, it is necessary to form nozzle holes in the nozzle plate in advance before bonding the nozzle plate to the actuator. In this case, when bonding the nozzle plate to the actuator, the adhesive material May enter the nozzle hole. When the adhesive enters the nozzle holes, the ink is not normally discharged from the nozzle holes, and the printed image has uneven density.

JP 2014-76558 A

  The problem to be solved by the present invention is to provide an ink jet head that prevents a reduction in the rigidity of the nozzle plate while taking the manufacturing process into consideration.

  The ink jet head according to the embodiment includes a plurality of pressure chamber walls that apply pressure to the pressure chamber, and a nozzle plate that is bonded to an end surface of the pressure chamber wall. The plurality of pressure chamber walls are arranged in a row so that the wall surfaces face each other. The nozzle plate includes a resin film provided with a plurality of nozzle holes, and a metal film disposed on a surface of the resin film and having an arrangement region of the nozzle holes. The nozzle plate is bonded to an end surface of the pressure chamber wall so that the nozzle hole is located between the pressure chamber wall and the pressure chamber wall.

It is a perspective view of the inkjet head of this embodiment. It is a development perspective view of an ink-jet head. It is a development perspective view of an ink-jet head. It is the elements on larger scale of a drive unit. It is the figure which removed the electrode pattern from the drive unit. (A) is a figure which shows the pressure chamber wall before a deformation | transformation, (B) is a figure which shows the pressure chamber wall after a deformation | transformation. (A) is a perspective view of the inkjet head from which the nozzle plate has been removed, and (B) is a plan view of the inkjet head from which the nozzle plate has been removed. (A) is the elements on larger scale of a nozzle plate, (B) is sectional drawing of a nozzle plate, (C) is sectional drawing of the nozzle plate on which the insulating film was laminated | stacked. It is sectional drawing of an inkjet head. It is a figure for demonstrating the manufacturing process of a base substrate. It is a figure for demonstrating the manufacturing process of a nozzle plate. It is a figure which shows a mode that a nozzle hole is formed in the sheet | seat used as a nozzle plate. (A) is the elements on larger scale of a nozzle plate, (B) is sectional drawing of a nozzle plate. It is a fragmentary sectional view of an inkjet head. It is a figure which shows a printer provided with the inkjet head of this embodiment.

  Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the drawings, the same or equivalent parts are denoted by the same reference numerals.

(Embodiment 1)
FIG. 1 is a perspective view showing an inkjet head 10 of the present embodiment. The ink jet head 10 of this embodiment is a side shooter type ink jet head of a share mode shared wall. The ink jet head 10 includes a base substrate 20, a frame 30, and a nozzle plate 40. In the following description, an orthogonal coordinate system including the X axis, the Y axis, and the Z axis is used. In the figure, the direction indicated by the arrow is the plus direction. In the following description, the plus direction of the Z-axis is upward and the opposite direction is downward.

  2 and 3 are developed perspective views of the ink jet head 10. Specifically, FIG. 2 is a diagram of the deployed inkjet head 10 as viewed from obliquely above, and FIG. 3 is a diagram of the deployed inkjet head 10 as viewed from obliquely below.

The base substrate 20 is a rectangular plate-like body whose longitudinal direction is the X-axis direction. The base substrate 20 is made of a ceramic such as alumina (Al ₂ O ₃ ), aluminum nitride (AlN), silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), or barium titanate (BaTiO ₃ ). The

Four openings 21 are formed in a line along the X-axis direction at the center of the base substrate 20 in the Y-axis direction. Further, the Y-axis minus direction side of the opening 21, four openings 22 ₁ in a row along the X-axis direction is formed. Further, the Y-axis plus direction side of the opening 21, four openings 22 ₂ in a row along the X-axis direction is formed. In the present embodiment, the inner diameter of the opening 21 is slightly larger than the inner diameter of the opening 22 (openings 22 ₁ and 22 ₂ ). An ink circulation system is connected to the openings 21 and 22. As a result, the opening 21 functions as an ink inlet, and the opening 22 functions as an ink outlet.

Two drive units 50 (drive units 50 ₁ and 50 ₂ ) are arranged on the upper surface of the base substrate 20. As shown in FIG. 2, the drive unit 50 ₁ is disposed between the opening 21 and the opening 22 ₁ , and the drive unit 50 ₂ is disposed between the opening 21 and the opening 22 ₂ .

  FIG. 4 is a partially enlarged view of the drive unit 50. FIG. 5 is a diagram in which the electrode pattern 60 is removed from the drive unit 50. The drive unit 50 includes a base material 51 bonded to the upper surface of the base substrate 20, a plurality of piezoelectric elements 52 supported by the base material 51, and an electrode pattern 60a.

  The base material 51 is a member whose longitudinal direction is the X-axis direction. The base material 51 is made of, for example, a piezoelectric material mainly composed of lead zirconate titanate. A protrusion 51 a that protrudes upward is formed on the upper surface of the base material 51. The protrusions 51a are formed at equal intervals along the X axis. The lower surface of the base material 51 is bonded to the upper surface of the base substrate 20 with an adhesive.

  The piezoelectric element 52 is, for example, a piezoelectric element mainly composed of lead zirconate titanate. The piezoelectric element 52 has a trapezoidal ZY section. The piezoelectric element 52 is bonded to the upper surface of the protruding portion 51a.

  The piezoelectric element 52 and the protrusion 51a are part of the pressure chamber wall (actuator) 50a. The pressure chamber wall 50a includes a piezoelectric element 52, a protruding portion 51a, and electrode patterns 60a disposed on both surfaces of the piezoelectric element 52 and the protruding portion 51a in the X-axis direction (hereinafter referred to as electrode surfaces). The pressure chamber walls 50a are arranged in a row in the X-axis direction so that the wall surfaces (electrode surfaces) face each other. As described above, both the piezoelectric element 52 and the protruding portion 51a are made of a piezoelectric material. The polarization directions of the piezoelectric element 52 and the protruding portion 51a are parallel to the Z axis, and the polarity of the piezoelectric element 52 and the polarity of the protruding portion 51a are reversed.

In the case of the drive unit 50 of this embodiment, the pressure chamber S is between the pressure chamber walls 50a. In this embodiment, as shown in FIG. 2, the arrangement pitch of the pressure chamber wall 50a of the drive unit 50 _1, the arrangement pitch of the pressure chamber wall 50a of the drive unit 50 ₂ are equal. The position of the pressure chamber wall 50a of the drive unit 50 ₂ is displaced in the X-axis direction. The pressure chamber S of the drive unit 50 _1, the pressure chamber S of the drive unit 50 _2, only half of the arrangement pitch of the pressure chamber wall 50a, is shifted in the X-axis direction.

  Further, as shown in FIG. 4, an electrode pattern 60 is formed from the inner wall surface of each pressure chamber S to the upper surface of the base substrate 20. The electrode pattern 60 is an electrode for applying a voltage to the pressure chamber wall 50a. The electrode pattern 60 is made of a conductor such as a nickel film. A driver IC (not shown) is connected to the electrode pattern 60.

  One electrode pattern 60 is disposed in one pressure chamber. By selectively applying a voltage to each electrode pattern 60, as shown in FIG. 6 (A), the pressure chamber wall 50a that is linear is bent as shown in FIG. 6 (B). Can be made. When the pressure chamber wall a is bent, the pressure in the pressure chamber S increases and ink is ejected from the nozzle holes 43.

  Returning to FIG. 2, the frame 30 is a frame-like body whose longitudinal direction is the X-axis direction. The frame 30 is made of, for example, ceramic. The frame 30 is slightly smaller than the base substrate 20.

  An opening 31 is formed in the center of the frame 30. On the inner wall surface of the opening 31, eight concave portions 32 that are recessed outward are formed. The frame 30 is bonded to the upper surface of the base substrate 20 as shown in FIG. FIG. 7B is a view of the frame 30 bonded to the base substrate 20 as viewed from above. The frame 30 is bonded so that the opening 22 of the base substrate 20 is positioned in the recess 32 of the frame 30.

  Returning to FIG. 2, the nozzle plate 40 is a rectangular sheet whose longitudinal direction is the X-axis direction. The size of the nozzle plate 40 on the XY plane is the same as the size of the frame 30 on the XY plane. That is, the size of the nozzle plate 40 in the X-axis direction is equal to the size of the frame 30 in the X-axis direction, and the size of the nozzle plate 40 in the Y-axis direction is equal to the size of the frame 30 in the Y-axis direction.

  FIG. 8A is a partially enlarged view of the nozzle plate 40. FIG. 8B is a cross-sectional view taken along line AA illustrated in FIG. The nozzle plate 40 is a laminated plate in which the resin film 41 and the metal film 42 are integrated without an adhesive layer. For example, the nozzle plate 40 is a copper clad laminate in which a copper foil is laminated on a resin film. The metal film 42 is harder than the resin film 41.

  The resin film 41 is composed of, for example, a polyimide film. The resin film 41 is a rectangular sheet whose longitudinal direction is the X-axis direction. The thickness of the resin film 41 is, for example, 25 μm to 50 μm.

The resin film 41, as shown in FIG. 2, circular nozzle holes 43 ₁ along the X-axis are formed at equal intervals. Further, the Y-axis plus direction side of the nozzle hole 43 _1, a circular nozzle holes 43 ₂ along the X-axis are formed at equal intervals. The arrangement pitch of the nozzle holes 43 (nozzle holes 43 ₁ and 41 ₂ ) is the same as the arrangement pitch in the X-axis direction of the pressure chamber walls 50a shown in FIG.

  As shown in FIG. 8B, the nozzle hole 43 has a larger diameter on the inner surface (surface in contact with the metal film 42) side than on the outer surface (surface not in contact with the metal film 42).

  The metal film 42 is a metal film having conductivity. The metal film 42 is, for example, a copper foil. The metal film 42 is thinner than the resin film 41. For example, the thickness of the metal film 42 is 15% to 99% of the thickness of the resin film 41.

  The metal film 42 is disposed on one surface of the resin film 41 without an adhesive layer. For example, the metal film 42 is formed on the resin film 41 by evaporating a metal that becomes the metal film 42 on the resin film 41. An opening 44 is formed in the metal film 42. The opening 44 is formed in the arrangement region of the nozzle hole 43. The size of the opening 44 is slightly larger than the size of the nozzle hole 43 so that the nozzle hole 43 is not blocked by the metal film 42. In the case of the present embodiment, the opening 44 is a square in which the length of one side is larger than the diameter on the inner surface side of the nozzle hole 43. The opening 44 is formed by etching or the like, for example.

  Note that a blank area B without the metal film 42 is provided between the edge of the resin film 41 and the edge of the metal film 42 as shown in FIG. The blank area B is formed by etching the outer periphery of the metal film 42. By providing the blank region B, the metal film 42 is less likely to be cracked by the force applied from the end side of the resin film 41.

FIG. 8C is a diagram illustrating a modified example of the nozzle plate 40. An insulating layer 45 is stacked on the surface of the metal film 42. The insulating layer 45 is for preventing the electrode pattern 60 formed in the pressure chamber S and the electrode pattern 60 formed in the adjacent pressure chamber S from being short-circuited via the metal film 42. The insulating layer 45 is made of, for example, a silicon dioxide (SiO ₂ ) film. The insulating layer 45 is formed by sputtering, for example.

  As shown in FIG. 1, the nozzle plate 40 is bonded to the upper surface of the frame 30 and the upper end surface of the pressure chamber wall 50 a through an adhesive layer 46. The end surface is a surface other than the wall surface of the pressure chamber wall 50a (the surface on which the electrode pattern 60a is formed in the example of FIG. 4). At this time, the nozzle plate 40 is bonded so that the metal film 42 is positioned inside (the drive unit 50 side). 6A, when the nozzle plate 40 is bonded to the frame 30, the nozzle holes 43 are located above the pressure chambers S, respectively.

  The adhesive layer 46 is formed by curing a thermosetting or ultraviolet curable adhesive. When the insulating layer 45 is not provided on the surface of the metal film 42, the adhesive layer 46 functions as an insulating layer that prevents conduction between the electrode pattern 60 a and the metal film 42. In this case, it is desirable that the adhesive layer 46 has a certain thickness in order to ensure that the adhesive layer 46 functions as an insulating layer. For example, the thickness t of the adhesive layer 46 is desirably 1 μm or more. The thickness t of the adhesive layer 46 is desirably 5 μm or less. This is because if the thickness of the adhesive layer 46 is increased more than necessary, the adhesive may flow at the time of bonding, and the thickness of the cured adhesive layer 46 may become non-uniform. Of course, the thickness t of the adhesive layer 46 may be set to 5 μm or more with emphasis on the function of the adhesive layer 46 as an insulating layer.

  FIG. 9 is a cross-sectional view of the inkjet head 10 shown in FIG. When the base substrate 20, the frame 30, and the nozzle plate 40 are integrated, the upper side of the pressure chamber S is blocked by the nozzle plate 40. As a result, an ink flow path is formed between the openings 21 and 22 and the pressure chamber S. As shown by solid line arrows in FIG. 9, the ink that has flowed from the opening 21 passes through the pressure chamber S and flows out from the opening 22 of the base substrate 20.

  Further, by selectively applying a voltage to the electrode pattern 60 while the ink is circulating, the pressure chamber wall 50a is shown in FIG. 6B from the state shown in FIG. 6A. It transforms into a state. As a result, ink is ejected from the nozzle holes 43 as indicated by the white arrows in FIG.

  Next, a method for manufacturing the inkjet head 10 will be described.

  First, a substrate 200 made of the same material as the base substrate 20 is prepared. Then, as shown in FIG. 10A, the substrate 200 is machined to form openings 21 and 22 (molding).

Next, the seat blocks 500 ₁ and 500 ₂ are prepared. The seat block 500 (seat blocks 500 ₁ and 500 ₂ ) is a rectangular parallelepiped member whose longitudinal direction is the X-axis direction. The sheet block 500 is formed, for example, by laminating a sheet 510 mainly composed of lead zirconate titanate and a sheet 520. The polarization directions of the sheets 510 and 520 are parallel to the normal line of the sheets 510 and 520 (Z-axis direction). The polarity of the sheet 510 and the polarity of the sheet 520 are opposite to each other. In the present embodiment, the polarity of the sheet 510 is the Z-axis plus direction, and the polarity of the sheet 520 is the Z-axis minus direction.

  Next, the two sheet blocks 500 are bonded to the upper surface of the base substrate 20. The seat block 500 is bonded between the opening 21 and the opening 22. For adhesion, a thermosetting adhesive may be used, or an ultraviolet curable adhesive may be used.

Next, using a dicing saw, to shape the seat block 500 (the seat block 500 ₁ and 500 _2). Specifically, both side surfaces in the Y-axis direction of the seat block 500 are cut obliquely as shown in FIG. Then, as shown in FIG. 10C, a plurality of grooves 500a parallel to the Y axis are formed in the sheet block 500 using a diamond saw. At this time, the intervals of the grooves 500a are equal. The groove 500a is not necessarily parallel to the Y axis. By forming the groove 500a in the sheet block 500, the sheet 520 is divided into small pieces. This small piece becomes the piezoelectric element 52 shown in FIG. Further, by forming the groove 500 a in the seat block 500, the protruding portion 51 a is formed in the sheet 510.

  Next, the electrode pattern 60 is formed from between the adjacent pressure chamber walls 50 a to the upper surface of the substrate 200. Specifically, as shown in FIG. 4, the electrode pattern 60 is formed from the inner wall surface of the pressure chamber S to the upper surface of the base substrate 20. Through the above steps, the base substrate 20 shown in FIG. 2 is completed.

  Next, a sheet 400 to be the nozzle plate 40 is prepared. FIG. 11A is a perspective view of the seat 400. The sheet 400 is a laminated plate in which the resin film 410 and the metal film 420 are integrated without an adhesive layer. As an example, the sheet 400 may be Upicel (registered trademark) N (a laminated plate having a polyimide thickness of 25 μm and a copper foil of 18 μm) manufactured by Ube Industries.

  An opening 44 is formed in the metal film 420 of the sheet 400 as shown in FIG. The opening 44 is formed in accordance with the position where the nozzle hole 43 is formed. The opening 44 is formed by etching. For example, a portion of the surface of the metal film 420 other than the portion that becomes the opening 44 is masked with a corrosion-resistant film. And the opening 44 is formed by corroding the part which is not masked with the chemical | medical agent (for example, ferric chloride solution) with metal corrosiveness. The outer periphery of the metal film 420 may be etched in the same manner as the opening 44 to form the blank region B in the sheet 400.

  Next, the frame 30 is bonded to the upper surface of the base substrate 20. Thereafter, the sheet 400 is bonded to the upper surface of the frame 30. At this time, the sheet 400 is bonded so that the metal film 420 is positioned inside. As a result, as shown in FIG. 6A, a pressure chamber S is formed in a portion surrounded by the pressure chamber wall 50a and the sheet 400.

  Next, laser light is irradiated from the upper surface of the sheet 400 to form nozzle holes 43 in the sheet 400. At this time, as shown in FIG. 12, the laser beam is irradiated in a conical shape so that the diameter on the inner surface side of the nozzle hole 43 is larger than the diameter on the outer surface side. The sheet 400 in which the nozzle holes 43 are formed becomes the nozzle plate 40.

  In addition, before irradiating a laser beam, you may cover parts other than the part used as the nozzle hole 43 with the protective film 470. FIG. For example, before the sheet 400 is bonded to the frame 30, a protective film 470 may be attached to the outer surface side of the sheet 400 as shown in FIG. 12. The protective film 470 may be a PET film having a thickness of 10 to 20 μm, for example. By attaching the protective film 470, the sheet 400 is less likely to be damaged by the laser light. After forming the nozzle holes 43 in the sheet 400, the protective film 470 is removed from the sheet 400. The inkjet head 10 is completed through the above steps.

  According to this embodiment, since the nozzle plate 40 is constituted by the resin film 41 and the metal film 42, the rigidity of the nozzle plate 40 is increased. As a result, the inkjet head 10 can eject ink from the nozzle holes 43 with high accuracy.

  The nozzle plate 40 is not a hard metal, but is composed of a resin film 41 and a metal film 42. After the nozzle plate 40 is bonded to the actuator, the nozzle holes 43 can be formed with laser light. Even if the adhesive layer 46 flows out to the position where the nozzle hole is formed, the adhesive layer 46 is scraped off by the laser beam, so that the adhesive layer 46 does not block the nozzle hole. Therefore, the ink jet head 10 can accurately eject ink from the nozzle holes.

  The nozzle plate 40 is a laminated plate in which the resin film 41 and the metal film 42 are integrated without an adhesive layer. Therefore, unlike the case where the resin film 41 and the metal film 42 are bonded with an adhesive, the nozzle plate 40 has a uniform thickness. As a result, since the rigidity of the nozzle plate 40 is uniform in each region on the plate, the inkjet head 10 can eject ink with high accuracy.

  The nozzle plate 40 is bonded so that the metal film 42 is located on the inner surface side. Since the metal film 42 is not exposed to the outer surface, the metal film 42 is not often peeled off from the nozzle plate 40 due to external stimulation. As a result, since the nozzle plate 40 can maintain rigidity for a long period of time, the inkjet head 10 can accurately eject ink for a long period of time.

  Further, the nozzle plate 40 has a blank area B between the end side of the resin film 41 and the end side of the metal film 42. Therefore, the metal film 42 is not often cracked by the force applied from the end side of the resin film 41. As a result, since the nozzle plate 40 can maintain rigidity for a long period of time, the inkjet head 10 can accurately eject ink for a long period of time.

(Embodiment 2)
The inkjet head 10 according to the second embodiment includes a base substrate 20, a frame 30, and a nozzle plate 40. The configurations of the base substrate 20 and the frame 30 are the same as those in the first embodiment.

  FIG. 13A is a partially enlarged view of the nozzle plate 40. FIG. 13B is a cross-sectional view taken along line AA illustrated in FIG. Similarly to the first embodiment, the nozzle plate 40 is a laminated plate in which the resin film 41 and the metal film 42 are integrated without an adhesive layer.

  As shown in FIGS. 13A and 13B, the metal film 42 is provided with slits 42 a and slits 42 b for separating the metal film 42. The slit 42a and the slit 42b are formed, for example, by etching the metal film 42.

Slit 42a is a slit for separating a region where the drive unit 50 ₁ of the metal film 42 is bonded, and a region where the drive unit 50 ₂ of the metal film 42 is adhered, the. As shown in FIG. 13A, the slit 42a is provided at the center in the Y-axis direction of the metal film 42 along the X-axis.

  The slit 42 b is a slit for separating the metal film 42 for each pressure chamber S. As shown in FIGS. 13A and 13B, the slit 42b is parallel to the wall surface of the pressure chamber wall 50a so as to penetrate the region where the metal film 42 and the end surface of the pressure chamber wall 50a are bonded. Provided. When the nozzle plate 40 is bonded to the drive unit 50, as shown in FIG. 14, the slit 42b is located above the pressure chamber wall 50a. Thereby, the metal film 42 becomes independent for each pressure chamber S.

  The other configuration of the inkjet head 10 is the same as that of the first embodiment, and thus the description thereof is omitted.

  According to the present embodiment, the nozzle plate 40 is provided with a slit for separating the metal film 42. As shown in FIG. 14, even if the metal film 42 and the electrode pattern 60 a come into contact with each other, the electrode pattern 60 formed in the pressure chamber S and the electrode pattern 60 formed in the adjacent pressure chamber S are connected to the metal film 42. There is no short circuit through. Therefore, it is not necessary to provide an insulating layer between the metal film 42 and the pressure chamber wall 50a.

(Embodiment 3)
Next, the printer 70 will be described. The printer 70 is an ink jet printer including an ink jet head having a configuration equivalent to that of the ink jet head 10 described in the first embodiment or the second embodiment. FIG. 15 is a diagram illustrating the printer 70. The printer 70 includes four colors of inkjet heads 10C, 10M, 10Y, and 10K of cyan, magenta, yellow, and black. The inkjet heads 10C, 10M, 10Y, and 10K have the same configuration as that of the inkjet head 10 according to the first or second embodiment.

  The printer 70 includes a housing 80, a paper feed cassette 71, a paper discharge tray 72, a holding roller 73, a transport device 74, and a reversing device 78. Around the holding roller 73, a holding device 75, an image forming device 76, a charge removing device 77, and a cleaning device 79 are provided in order from the upstream side to the downstream side. In addition, a paper position sensor 107 that detects the leading end position of the paper P and a temperature sensor 108 that detects the temperature inside the printer 70 are provided inside the printer 70.

  The holding roller 73 is a roller that holds and rotates the paper P. The holding roller 73 includes a rotating shaft 71 a, a cylindrical cylindrical frame 91 made of aluminum, and an insulating layer 92 formed on the surface of the cylindrical frame 91. The cylindrical frame 91 is grounded.

  The transport device 74 is a device that transports the paper P along the transport path A1. The transport path A <b> 1 is formed from the paper feed cassette 71 to the paper discharge tray 72 via the holding roller 73. The conveyance device 74 includes a plurality of guide members 81 to 83 provided along the conveyance path A1, a plurality of first conveyance rollers, and a plurality of second conveyance rollers. The transport device 74 includes a pickup roller 84 and a paper feed roller pair 85 as a first transport roller. The paper P is transported to the inkjet heads 10C, 10M, 10Y, and 10K by the first transport roller. In addition, as a second transport roller, a registration roller pair 86, a separation roller pair 87, a transport roller pair 88, and a discharge roller pair 89 are provided. The sheet P is transported to the outside of the printer 70 along the transport path A1 by the second transport roller.

  The holding device 75 is a device that attracts the paper P to the outer peripheral surface of the holding roller 73. The holding device 75 includes a pressing device 93 and a suction device 94. The pressing device 93 is a device that presses the paper P against the holding roller 73. The pressing device 93 includes a rotating shaft 95 c, a pressing roller 95 disposed to face the surface of the holding roller 73, and a pressing motor that drives the pressing roller 95. The outer peripheral surface of the pressing roller 95 is covered with an insulating layer 95b. The suction device 94 is a device that sucks the paper P onto the holding roller 73. The suction device 94 includes a charging roller 97. The charging roller 97 includes a charging shaft 97a that can be charged, and a surface layer portion 97b formed on the outer periphery of the charging shaft 97a. When electric power is supplied to the charging roller 97 while the charging roller 97 is close to the holding roller 73, a potential difference is generated between the charging roller 97 and the grounded cylindrical frame 91. As a result, an electrostatic force is generated in a direction in which the paper P is attracted to the holding roller 73, and the paper P is attracted to the surface of the holding roller 73.

  The image forming apparatus 76 is an apparatus that forms an image on the paper P. The image forming apparatus 76 includes four inkjet heads 10C, 10M, 10Y, and 10K disposed above the holding roller 73. The four color inkjet heads 10C, 10M, 10Y, and 10K eject ink onto the paper P. As a result, an image is formed on the paper P.

  The neutralization peeling device 77 is a device that peels the paper P from the holding roller 73. The static elimination apparatus 77 includes a static elimination apparatus 101 and a peeling apparatus 102. The neutralization device 101 is a device that neutralizes the paper P. The neutralization device 101 includes a neutralization roller 103 that is provided on the downstream side of the image forming apparatus 76 and can be charged. The static eliminator 101 supplies the electric charge to neutralize the paper P so that the paper P is easily peeled off from the holding roller 73. The peeling device 102 is a device that peels the paper P from the surface of the holding roller 73 after static elimination. The peeling device 102 includes a separation claw 105 provided on the downstream side of the static elimination device 101. The separation claw 105 peels the paper P from the surface of the holding roller 73.

  The reversing device 78 is a device that reverses the paper P peeled off by the peeling device 102. The reversing device 78 reverses the paper P by, for example, guiding the paper P along a reversing path for switching back the paper P.

  The cleaning device 79 is a device that cleans the holding roller 73. The cleaning device 79 includes a cleaning member. The surface of the holding roller 73 is cleaned by the rotation of the holding roller 73 while the cleaning member is in contact with the surface of the holding roller 73.

  The printer 70 described above includes the inkjet heads 10C, 10M, 10Y, and 10K having the same configuration as the inkjet head 10. The printer 70 can accurately eject ink onto the paper P as a recording medium. As a result, the printer 70 can print an image on a recording medium with high accuracy.

  In addition, each above-mentioned embodiment shows an example, respectively, A various change and application are possible.

  For example, in the above-described embodiment, the metal film 42 has been described as being formed on the resin film 41 by vapor-depositing a metal that becomes the metal film 42 on the resin film 41, but the metal film 42 is formed on the resin film 41. The method of forming 42 is not limited to vapor deposition. For example, the metal film 42 may be formed on the resin film 41 by heating and pressurizing a metal foil to be the metal film 42 on the resin film 41. Also by this method, the metal film 42 can be disposed on the resin film 41 without an adhesive layer.

  Moreover, in the above-mentioned embodiment, although the resin film 41 was demonstrated as what is comprised from a polyimide (PI), the raw material of the resin film 41 is not restricted to a polyimide. For example, the resin film 41 is made of polyamide (PA), polycarbonate (PC), polyacetal (POM), polybutylene terephthalate (PBT), fluorine resin (FR), modified polyphenylene ether (m-PPE), polyamideimide (PAI), Polyetherimide (PEI), polyetheretherketone (PEEK), polyethersulfone (PESU), polysulfone (PSU), polyarylate (PAR), polyphenylene sulfide (PPS), polyester elastomer (TPC), liquid crystal polymer (LPC) Or the like. The resin film 41 may be made of a resin reinforced with glass fibers such as glass fiber reinforced polyethylene terephthalate (GF-PET).

  In the above-described embodiment, the metal film 42 is described as being made of copper (Cu), but the material of the metal film 42 is not limited to copper. For example, the metal film 42 is made of a metal such as aluminum (Al), gold (Au), silver (Ag), titanium (Ti), chromium (Cr), iron (Fe), tin (Sn), nickel (Ni). It may be configured. The metal film 42 may be made of an alloy such as stainless steel (SUS).

  In the above-described embodiment, the thickness of the metal film 42 has been described as being thinner than the thickness of the resin film 41, but the thickness of the metal film 42 may be greater than the thickness of the resin film 41. Of course, the thickness of the metal film 42 may be the same as the thickness of the resin film 41.

In the above-described embodiment, the base material 51 and the piezoelectric element 52 are described as being composed of a piezoelectric material mainly composed of lead zirconate titanate (PZT). The constituting piezoelectric material is not limited to lead zirconate titanate. For example, the piezoelectric material constituting the base material 51 and the piezoelectric element 52 may be barium titanate (BaTiO ₃ ), lead titanate (PbTiO ₃ ), or the like.

  In the above-described embodiment, the shape of the opening 44 has been described as a square, but the shape of the opening 44 is not limited to a square. For example, the opening 44 may be a rectangle whose short side is larger than the diameter on the inner surface side of the nozzle hole 43, or may be a circle whose diameter is larger than the diameter on the inner surface side of the nozzle hole 43. Further, it may be the same shape and the same size as the inner surface side of the nozzle hole 43.

  Moreover, although the shape of the nozzle hole 43 was demonstrated as what was circular in the above-mentioned embodiment, the shape of the nozzle hole 43 is not restricted circular. The shape of the nozzle hole 43 may be oval or oval.

In the embodiment described above, the nozzle plate 40 has been described as comprising a nozzle hole 43 of the two rows of the nozzle holes 43 ₁ and 43 _2, the nozzle holes 43 is not limited to two rows. The nozzle holes 43 may be in one row or in three or more rows.

  In the above-described embodiment, the blank area B without the metal film 42 is provided along the edge of the nozzle plate 40. However, the blank area B may not be provided.

  Further, in the above-described embodiment, the opening 44 and the blank region B are formed in the nozzle plate 40 by etching away the portion that becomes the opening 44 and the blank region B from the metal film 420 uniformly formed on the resin film 41. Formed. However, the method of forming the opening 44 and the blank region B is not limited to etching. For example, the opening 44 may be formed by adding the metal film 42 to the resin film 41 so that the opening 44 and the blank region B are formed. For example, a metal film 42 is formed on the resin film 41 by forming a resist in a portion where the opening 44 and the blank region B are formed on the resin film 41 and performing electrolysis or electroless plating on a portion without the resist. Thereby, the portion where the resist is formed becomes the opening 44 and the blank region B.

  In the above-described embodiment, the base substrate 20 and the frame 30 are described as being made of ceramic. However, the material of the base substrate 20 and the frame 30 is not limited to ceramic. The base substrate 20 and the frame 30 may be made of resin. Further, for example, the base substrate 20 and the frame 30 may be made of metal as long as the surface is covered with an insulating material and insulation is ensured.

  In the above-described embodiment, the inkjet head 10 is described as a side shooter type inkjet head that pushes ink in the depth direction (Z-axis direction) of the pressure chamber S. However, the inkjet head 10 is a side shooter. It is not limited to the type of inkjet head. For example, the inkjet head 10 may be an edge shooter type inkjet head that pushes ink in the longitudinal direction (Y-axis direction) of the pressure chamber S.

  The inkjet head 10 according to the above embodiment is an example, and the number of openings 21 and 22 formed in the base substrate 20, the number of nozzle holes 43, and the number of pressure chamber walls 50 a depend on the use and resolution of the inkjet head 10. Accordingly, it can be appropriately changed.

  Although the embodiment of the present invention has been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10,10Y, 10M, 10C, 10K, ... inkjet head 40 ... nozzle plate 41,410 ... resin film 42,420 ... metal film 50, 50 _1, 50 2 _... drive unit 52 ... piezoelectric elements 70 ... printer

Claims (5)

A plurality of pressure chamber walls arranged in a row so that the wall faces each other, and applying pressure to the pressure chamber;
A resin film provided with a plurality of nozzle holes, and a metal film disposed on the surface of the resin film and having an arrangement region of the nozzle holes as an opening, and the pressure chamber wall and the pressure chamber wall A nozzle plate bonded to an end surface of the pressure chamber wall so that the nozzle hole is located between the nozzle plate,
Inkjet head. The metal film is disposed on one surface of the resin film.
The nozzle plate is arranged so that the surface on which the metal film is formed is located on the pressure chamber wall side,
The inkjet head according to claim 1. The nozzle plate is a laminated plate in which the resin film and the metal film are integrated without an adhesive layer.
The inkjet head according to claim 1 or 2. The pressure chamber wall is composed of a piezoelectric element in which both wall surfaces are electrode surfaces,
The metal film is
Arranged on the pressure chamber wall side surface of the resin film,
The nozzle plate and the end face of the pressure chamber wall are separated for each pressure chamber by a slit provided in parallel to the wall surface so as to penetrate the region.
The inkjet head according to any one of claims 1 to 3. The inkjet head according to any one of claims 1 to 4,
A transport roller for transporting paper in the direction of the inkjet head,
Printer.

Images