JP2012192705A - Liquid discharge head and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid droplet ejection head that improves productivity and reliability by decreasing variation of a vibratable area of a vibrating plate member.SOLUTION: The liquid droplet ejection head includes: a flow channel plate that forms a liquid chamber 6 to which a plurality of nozzles 4 that discharge the liquid droplet communicate; a vibration plate member 2 that forms the wall surface of liquid chamber 6; a piezoelectric actuator 100 that is provided at the surface of the vibration plate member 2 at the other side of the liquid chamber 6 to displace the vibratable area 2a of the vibration plate member 2; and a support member 20 connected to the channel plate 1 directly or through the vibration plate member 2. The support member 20 is provided with a backing part 22 opposing to a partition wall 5 between adjoining liquid chambers 6 connected to the surface of the vibration plate member 2 at the other side of the liquid chamber 6. The width W2 in the nozzle arrangement direction of the backing part 22 is wider than the width W1 in the nozzle arrangement direction of the partition wall 5 between the liquid chambers 6 and the width W3 in the nozzle arrangement direction of the vibratable area 2a of the vibration plate member 2 is defined by the width W2 in the nozzle arrangement direction of the backing part 22.

Description

  The present invention relates to a liquid discharge head and an image forming apparatus.

  As an image forming apparatus such as a printer, a facsimile, a copying machine, a plotter, or a complex machine of these, for example, a liquid discharge recording type image forming using a recording head composed of a liquid discharge head (droplet discharge head) that discharges ink droplets. An apparatus (for example, an ink jet recording apparatus) is known. This liquid discharge recording type image forming apparatus means that ink droplets are transported from a recording head (not limited to paper, including OHP, and can be attached to ink droplets and other liquids). Yes, it is also ejected onto a recording medium or a recording medium, recording paper, recording paper, etc.) to form an image (recording, printing, printing, and printing are also used synonymously). And a serial type image forming apparatus that forms an image by ejecting liquid droplets while the recording head moves in the main scanning direction, and a line type head that forms images by ejecting liquid droplets without moving the recording head There are line type image forming apparatuses using

  In the present application, the “image forming apparatus” of the liquid discharge recording method is an apparatus that forms an image by discharging liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, or the like. In addition, “image formation” means not only giving an image having a meaning such as a character or a figure to a medium but also giving an image having no meaning such as a pattern to the medium (simply It also means that a droplet is landed on a medium). “Ink” is not limited to ink, but is used as a general term for all liquids capable of image formation, such as recording liquid, fixing processing liquid, and liquid. DNA samples, resists, pattern materials, resins and the like are also included. The term “paper” is not limited to paper, but includes the above-described OHP sheet, cloth, and the like, and means that ink droplets adhere to the recording medium, recording medium, recording paper, recording It is used as a general term for what includes what is called paper. In addition, the “image” is not limited to a planar image, and includes an image given to a three-dimensionally formed image and an image formed by three-dimensionally modeling a solid itself.

  By the way, in the liquid ejection head, high dimensional accuracy is required in order to suppress variation in characteristics between each bit (each nozzle), and in particular, a diaphragm width (in a vibration possible region of a head using a diaphragm such as a piezoelectric element). Since the width) greatly affects the droplet discharge characteristics, high dimensional accuracy is required. For example, when the nozzles are arranged at 300 dpi, it is necessary to suppress variation in diaphragm width of each bit to ± 2 μm or less.

  Therefore, conventionally, a backing material having a partition wall that is bonded to the piezoelectric vibrator side of the flow path forming substrate and defines a recess made of a space that does not hinder its movement is used as the partition wall of the flow path forming substrate. There is known a structure that is fixed to a flow path forming substrate so as to be opposed to (Patent Document 1).

  In addition, the pressure generating chamber has a wide portion wider than the piezoelectric active portion constituting the piezoelectric element on the side of the piezoelectric element and a narrow portion narrower than the wide portion, and ends in the width direction of the wide portion. The region corresponding to the portion is provided with a vibration regulating layer having at least a discontinuous piezoelectric layer that is discontinuous from the piezoelectric layer that extends from the region facing the pressure generating chamber to the outside of the region. The thing made into the structure which has it is also known (patent document 2).

  Also, in the piezoelectric head having a bi-pitch structure in which the stacked piezoelectric pillars and the support pillars are alternately arranged, the width of the thick part joined to the support pillar part of the diaphragm is made wider than the width of the liquid chamber interval wall, There are also known ones in which the deformable region of the diaphragm is restricted by the width of the thick part (Patent Document 3), and the support part is formed wider than the liquid chamber interval wall (Patent Document 4).

JP 11-291497 A JP 2001-287360 A JP-A-11-105283 JP 2008-149588 A

  However, in the configuration disclosed in Patent Document 1, the diaphragm width is greatly affected by the processing accuracy during liquid chamber processing, and it is difficult to satisfy the required value of the variation in diaphragm width. . Further, as disclosed in Patent Document 2, instead of determining the diaphragm width by the processing accuracy of the pressurized liquid chamber, an auxiliary layer is provided on the first substrate (vibration plate, piezoelectric element forming substrate), By defining the diaphragm width with this auxiliary layer, the variation in diaphragm width can be reduced and the variation in droplet ejection characteristics between bits can be reduced, but a layer (film) that defines a diaphragm width that is not originally required. There is a problem that man-hours and costs increase, yield decreases, and it is difficult to efficiently produce a head having high quality and high reliability.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to improve the droplet discharge characteristics by reducing the variation in the vibratable region with a simple configuration, thereby improving the productivity and reliability.

In order to solve the above-described problem, a liquid discharge head according to the present invention includes:
A flow path member that forms a liquid chamber in which a plurality of nozzles that discharge droplets communicate with each other;
A diaphragm member forming at least one wall surface of the liquid chamber;
A piezoelectric member that is provided on a side surface of the diaphragm member opposite to the liquid chamber and displaces a viable region of the diaphragm member;
A support member joined directly or through the diaphragm member to the flow path member,
The support member is provided with a backing portion bonded to a surface opposite to the liquid chamber of the diaphragm member so as to face a partition between adjacent liquid chambers,
The width of the backing portion in the nozzle arrangement direction is wider than the width of the partition wall between the liquid chambers in the nozzle arrangement direction,
The width in the nozzle arrangement direction of the vibrating region of the diaphragm member is defined by the width of the backing portion in the nozzle arrangement direction.

  Here, the said backing part can be set as the structure currently formed with the base material of the said supporting member.

  In addition, the backing portion may be formed of a film formed on the base material of the support member.

  The image forming apparatus according to the present invention includes the liquid discharge head according to the present invention.

  According to the liquid ejection head of the present invention, the support member is provided with the backing portion that is opposed to the partition wall between the adjacent liquid chambers and is bonded to the surface on the opposite side of the liquid chamber of the vibration plate member. The width in the nozzle arrangement direction is wider than the width in the nozzle arrangement direction of the partition walls between the liquid chambers, and the width in the nozzle arrangement direction of the vibrating region of the diaphragm member is defined by the width in the nozzle arrangement direction of the backing portion As a result, the variation in the vibration possible region of the diaphragm can be reduced with a simple configuration, the droplet ejection characteristics are improved, and the productivity and reliability are also improved.

  According to the image forming apparatus according to the present invention, since the liquid ejection head according to the present invention is provided, stable droplet ejection can be performed.

FIG. 3 is a perspective view illustrating a main part of the liquid ejection head according to the first embodiment of the present invention. It is principal part cross-sectional explanatory drawing along the nozzle arrangement direction of the head. It is sectional explanatory drawing in alignment with the direction orthogonal to the nozzle arrangement direction of the head. It is principal part cross-sectional explanatory drawing along the nozzle arrangement | sequence direction explaining the liquid discharge head which concerns on 2nd Embodiment of this invention with the manufacturing process. FIG. 5 is a cross-sectional explanatory diagram of a main part along a nozzle arrangement direction for explaining a process following FIG. 4. It is principal part sectional explanatory drawing along the nozzle arrangement direction of the liquid discharge head which concerns on 3rd Embodiment of this invention. It is a side explanatory view of a mechanism portion showing an example of an image forming apparatus according to the present invention. It is principal part plane explanatory drawing of the mechanism part.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. A liquid discharge head according to a first embodiment of the present invention will be described with reference to FIGS. 1 is an explanatory perspective view of the main part of the head, FIG. 2 is a sectional explanatory view along the nozzle arrangement direction (liquid chamber longitudinal direction) of the head, and FIG. 3 is a direction orthogonal to the nozzle arrangement direction of the head (liquid It is front explanatory drawing along a room short side direction.

  The liquid discharge head includes a flow path plate (flow path member, liquid chamber substrate) 1 as a first substrate, a vibration plate member 2 provided on one surface of the flow path plate 1, and the other of the flow path plate 1. And a plurality of individual liquid chambers (pressurized liquid chambers, pressures) as individual channels through which a plurality of nozzles 4 for discharging liquid droplets (liquid droplets) communicate with each other. Also referred to as a chamber, a pressure chamber, a flow path, etc., hereinafter referred to as a “liquid chamber”) 6, a fluid resistance portion 7 that also serves as a supply path for supplying ink to the liquid chamber 6, and the fluid resistance portion 7 Thus, a common liquid chamber 8 communicating with the liquid chamber 6 is formed. The nozzle arrangement direction of each liquid chamber 6 is partitioned by a liquid chamber interval wall 5.

  The flow path member 1 forms openings such as the liquid chamber 6, the fluid resistance portion 7, the communication portion 8, etc. by etching the SUS substrate using an acidic etchant or machining such as punching (pressing). ing. A silicon substrate or the like can be used as the flow path member 1.

  The diaphragm member 2 has a vibrable region (diaphragm portion) 2a that is a vibrable region that forms a wall surface corresponding to each liquid chamber 6, and is outside the surface of the vibrable region 2a (the surface opposite to the liquid chamber 6). The piezoelectric actuator 100 including the piezoelectric layer 12 as driving means (actuator means, pressure generating means) for deforming the vibrable region 2a is disposed on the side.

  The piezoelectric actuator 100 includes a common electrode film 11 formed on the surface of the diaphragm member 2 opposite to the liquid chamber 6, a piezoelectric layer 12 formed on the common electrode film 11, and a piezoelectric layer 12 on the piezoelectric layer 12. The individual electrode film 13 is formed.

  A support member 20 is joined to the flow path plate 1 directly or via the vibration plate member 2 on the piezoelectric actuator 100 side. The support member 20 is formed with a common liquid supply 10 communicating with the common liquid chamber 8 and a liquid supply port 30 for supplying liquid from the outside to the common liquid supply flow path 10, and corresponding to each piezoelectric actuator 100. A recessed portion 21 is formed by a counterbore hole, and a portion between the recessed portions 21 is a backing portion 22 that backs (reinforces) a portion corresponding to the liquid chamber interval wall 5.

  The width W2 of the backing portion 22 in the nozzle arrangement direction is formed wider than the width W1 of the partition walls 5 between adjacent liquid chambers in the nozzle arrangement direction. As a result, the width W3 in the nozzle arrangement direction of the vibratable region 2a of the diaphragm member 2 is defined by the width W2 of the backing portion 22.

  In the liquid ejection head configured as described above, by applying a driving pulse to the individual electrode 13 of the piezoelectric actuator 100 corresponding to the nozzle 4 that causes droplet ejection based on image data from a control unit (not shown), The piezoelectric layer 12 itself contracts in a direction parallel to the diaphragm member 2 due to the electrostrictive effect, and the viable region 2a of the diaphragm member 2 bends in the direction of the liquid chamber 6. As a result, the pressure in the liquid chamber 6 rises rapidly, and droplets are ejected from the nozzle 4.

  In addition, since this liquid discharge head uses a thin film piezo as a piezoelectric actuator, the width of the support member (backing portion) can be formed by fine processing, and the width and pitch between the backing portions can be arbitrarily controlled. And can correspond to a high-density nozzle arrangement (for example, 300 dpi or more).

  Next, after the drive pulse is applied, the contracted piezoelectric layer 12 returns to its original position, so that the vibrable region 2a of the deflected diaphragm member 2 returns to its original position, and the liquid chamber 6 is in the common liquid chamber 8. The pressure is negative compared to the inside, and the liquid is supplied from the common liquid chamber 8 to the liquid chamber 6 via the fluid resistance portion 7. By repeating this, droplets are continuously ejected, and an image can be formed on a recording medium (paper) facing the liquid ejection head.

  Here, in this liquid ejection head, the width W3 in the nozzle arrangement direction of the vibration possible region 2a of the diaphragm member 2 is defined by the width W2 of the backing portion 22, so the width of the vibration possible region can be reduced with a simple configuration. Variations can be reduced and productivity and reliability can be improved.

Next, a liquid ejection head according to a second embodiment of the present invention will be described with reference to FIGS. 4 to 6 are cross-sectional explanatory views of main parts along the nozzle arrangement direction.
As shown in FIG. 4A, a constituent film of the vibration plate member 2 is formed on, for example, an LP-CVD method on a silicon single crystal substrate 201 (for example, 400 μm thick) having a plane orientation (110) forming the flow path plate 1. Alternatively, a silicon oxide film 202 (for example, a thickness of 600 nm) is formed by a heat treatment film formation method, and then a silicon nitride film 203 (for example, 500 nm) is formed by, for example, LP-CVD as a rigidity adjusting film for the diaphragm 2. Then, a silicon oxide film 204 (for example, a thickness of 600 nm) is formed by LP-CVD to form the diaphragm member 2.

Here, the constituent film of the diaphragm member 2 can adjust the rigidity of the diaphragm member 2 such as ZrO ₂ and Al ₃ O _{2 in consideration} of the function of the diaphragm member and process consistency. A film having a Young's modulus may be used. Further, the silicon oxide film 202 functions as an etching stop layer at the time of etching for forming the liquid chamber 6 later, but other material films may be used as long as the function is satisfied.

  Next, as shown in FIG. 4B, the common electrode film 11 made of Ti and Pt is formed by sputtering, for example, 30 nm and 100 nm, respectively. Next, a PZT film having a thickness of 2 μm is formed as the piezoelectric layer 12 on the common electrode film 11 by sputtering, for example, and thereafter, Pt to be an individual electrode 13 later is formed by sputtering to a thickness of 100 nm. Here, the film formation method of the piezoelectric layer 12 is not limited to the sputtering method, and may be formed by, for example, an ion plating method, an air sol method, a sol-gel method, an ink jet method, or the like.

  Next, as shown in FIG. 4C, the individual electrode film 13 and the piezoelectric layer 12 are patterned by a lithoetch method in order to form the piezoelectric actuator 100 at a position corresponding to the liquid chamber 6 to be formed later.

  Next, although not shown, a portion of the diaphragm member 2 that forms part of the common liquid chamber 8 is removed by a lithoetch method.

  Then, as shown in FIG. 4D, the common liquid supply flow path 10, the liquid supply port 30, and the concave portion 21 and the backing portion 22 that are counterbore holes are vibrated, for example, a support member 20 formed of a glass material. Bonded to the plate member 2. The bonding may be bonding with an adhesive or direct bonding, but direct bonding without using an adhesive is suitable.

  Here, a glass material is applied as the support member 20, but a silicon single crystal substrate or the like may be used. However, in the case of a silicon single crystal substrate, when a liquid chamber 6 or the like is formed in the silicon substrate 201 by etching, a common film is supplied with a resistant film such as a silicon oxide film or a silicon nitride film so that the support member 20 is not etched. It is necessary to form on the inner wall surface of the flow path 10 and the surface of the support member 20.

  Next, as shown in FIG. 5A, the silicon substrate 201 is polished to a desired thickness t (for example, a thickness of 80 μm). Etching may be used in addition to the polishing method.

  Next, as shown in FIG. 5B, the liquid chamber 6, the common liquid chamber 8 and the partition wall 5 other than the fluid resistance portion 7 are covered with a resist by a litho method. Thereafter, anisotropic wet etching is performed with an alkaline solution (KOH solution or TMHA solution) to form the liquid chamber 6, the common liquid chamber 8 and the fluid resistance portion 7 described above. Here, the width W2 of the backing portion 22 is necessarily larger than the width W1 of the partition wall 5. Therefore, the short side length width (width in the nozzle arrangement direction) of the diaphragm member 2 is defined by the interval between the adjacent backing portions 22.

  Next, as shown in FIG. 5C, the nozzle plate 3 having the nozzle 4 opened is joined to complete the liquid ejection head.

  Thus, by making the width W2 of the backing portion 22 of the support member 20 wider than the width W1 of the liquid chamber interval wall 5 of the flow path plate 1, the short side width W3 of the vibrable region 2a of the diaphragm member 2 is , Defined by the interval between adjacent backing portions 22.

  Therefore, the vibration plate member 2 can be processed with the processing accuracy when forming the backing portion 22 that can be processed with better dimensional accuracy than when forming the liquid chamber without being affected by the dimensional accuracy when forming the liquid chamber 6. The width of the vibratable region 2a can be defined, and can be formed with simple steps and man-hours. A highly accurate, high-density, high-reliability head can be stably obtained at low cost.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is an explanatory cross-sectional view of a main part along the nozzle arrangement direction of the head according to the embodiment.
In the present embodiment, a joint portion between the backing portion 22 of the support member 20 and the flow path plate 1 side is formed by a film 402 formed on the base material 401 of the support member 20.

  Specifically, when the concave portion 21 is formed with counterbore on the base material 401 forming the support member 20, the film 42 is formed by leaving the counterbore forming mask without being removed. For example, when the base material 401 of the support member 20 is a silicon single crystal substrate, a silicon oxide film or a silicon nitride film is used as a counterbore forming mask. Thereby, the film 402 is formed of a silicon oxide film or a silicon nitride film.

  In this case, in order to define the width of the vibratable region 2a of the diaphragm member 2, the thickness of the counterbore forming mask (film 402) is at least 1 μm or more.

  By doing so, the concave portion forming mask (the counterbore forming mask) of the support member 20 can be used as it is as a portion that defines the short side width of the vibration possible region 2a of the diaphragm member 2, and the counterbore formation The step of removing the mask for use can be omitted. Further, when the counterbore forming mask is removed, the width of the recess 21 is affected by the processing dimension accuracy of the counterbore forming mask and the processing dimension accuracy when forming the recess (counterbore). Since it is determined only by the dimensional accuracy of the mask, the accuracy of the width W2 of the backing portion 22 is higher than that of the second embodiment.

  Thereby, compared with the said 2nd Embodiment, cost reduction (omission of a counterbore formation mask removal process) can be achieved, and the width | variety of the vibration possible area | region of a diaphragm member can be prescribed | regulated with high precision.

  In addition, the liquid discharge head of each of the above embodiments and a head tank that supplies liquid to the liquid discharge head can be integrated.

Next, an example of the image forming apparatus according to the present invention including the liquid discharge head according to the present invention will be described with reference to FIGS. FIG. 7 is a schematic side view for explaining the mechanism part of the apparatus, and FIG. 8 is a plan view for explaining a main part of the mechanism part.
This image forming apparatus is a serial type image forming apparatus, and a carriage 233 is slidably held in the main scanning direction by main and slave guide rods 231 and 232 which are guide members horizontally mounted on the left and right side plates 221A and 221B. The main scanning motor that does not perform moving scanning in the direction indicated by the arrow (carriage main scanning direction) via the timing belt.

  The carriage 233 includes a plurality of recording heads 234 including the liquid ejection head according to the present invention for ejecting ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (K). Nozzle rows composed of nozzles are arranged in the sub-scanning direction orthogonal to the main scanning direction, and are mounted with the ink droplet ejection direction facing downward.

  The recording head 234 is configured by attaching liquid ejection heads 234a and 234b each having two nozzle rows to one base member, and one nozzle row of one head 234a has a black (K) droplet. The other nozzle row ejects cyan (C) droplets, the other nozzle row of the other head 234b ejects magenta (M) droplets, and the other nozzle row ejects yellow (Y) droplets. . Note that, here, a two-head configuration is used to eject four color droplets, but a liquid ejection head for each color may be provided.

  The carriage 233 is equipped with sub tanks 235a and 235b (referred to as “sub tank 235” when not distinguished) for supplying ink of each color corresponding to the nozzle rows of the recording head 234. The sub tank 235 is supplied with ink of each color from the ink cartridge 210 of each color by the supply unit 224 via the supply tube 236 of each color.

  On the other hand, as a paper feeding unit for feeding the paper 242 stacked on the paper stacking unit (pressure plate) 241 of the paper feed tray 202, a half-moon roller (feeding) that separates and feeds the paper 242 one by one from the paper stacking unit 241. A separation pad 244 made of a material having a large coefficient of friction is provided opposite to the sheet roller 243 and the sheet feeding roller 243, and the separation pad 244 is urged toward the sheet feeding roller 243 side.

  In order to feed the sheet 242 fed from the sheet feeding unit to the lower side of the recording head 234, a guide member 245 for guiding the sheet 242, a counter roller 246, a conveyance guide member 247, and a tip pressure roller. And a conveying belt 251 which is a conveying means for electrostatically attracting the fed paper 242 and conveying it at a position facing the recording head 234.

  The conveyor belt 251 is an endless belt, and is configured to wrap around the conveyor roller 252 and the tension roller 253 so as to circulate in the belt conveyance direction (sub-scanning direction). In addition, a charging roller 256 that is a charging unit for charging the surface of the transport belt 251 is provided. The charging roller 256 is disposed so as to come into contact with the surface layer of the conveyor belt 251 and to rotate following the rotation of the conveyor belt 251. The transport belt 251 rotates in the belt transport direction when the transport roller 252 is rotationally driven through timing by a sub-scanning motor (not shown).

  Further, as a paper discharge unit for discharging the paper 242 recorded by the recording head 234, a separation claw 261 for separating the paper 242 from the transport belt 251, a paper discharge roller 262, and a paper discharge roller 263 are provided. A paper discharge tray 203 is provided below the paper discharge roller 262.

  A double-sided unit 271 is detachably attached to the back surface of the apparatus main body. The duplex unit 271 takes in the paper 242 returned by the reverse rotation of the transport belt 251, reverses it, and feeds it again between the counter roller 246 and the transport belt 251. The upper surface of the duplex unit 271 is a manual feed tray 272.

  Further, a maintenance / recovery mechanism 281 for maintaining and recovering the nozzle state of the recording head 234 is disposed in a non-printing area on one side in the scanning direction of the carriage 233. The maintenance / recovery mechanism 281 includes cap members (hereinafter referred to as “caps”) 282a and 282b (hereinafter referred to as “caps 282” when not distinguished) for capping each nozzle surface of the recording head 234, and nozzle surfaces. A wiper blade 283 that is a blade member for wiping the ink, and an empty discharge receiver 284 that receives liquid droplets when performing empty discharge for discharging liquid droplets that do not contribute to recording in order to discharge thickened ink. Yes.

  In addition, in the non-printing area on the other side of the carriage 233 in the scanning direction, idle ejection that receives droplets when performing idle ejection that ejects droplets that do not contribute to recording in order to discharge ink that has been thickened during recording or the like. A receiver 288 is disposed, and the idle discharge receiver 288 is provided with an opening 289 along the nozzle row direction of the recording head 234 and the like.

  In this image forming apparatus configured as described above, the sheets 242 are separated and fed one by one from the sheet feeding tray 202, and the sheet 242 fed substantially vertically upward is guided by the guide 245, and is conveyed to the conveyor belt 251 and the counter. It is sandwiched between the rollers 246 and conveyed, and further, the leading end is guided by the conveying guide 247 and pressed against the conveying belt 251 by the leading end pressure roller 249, and the conveying direction is changed by approximately 90 °.

  At this time, a positive output and a negative output are alternately applied to the charging roller 256, that is, an alternating voltage is applied, and a charging voltage pattern in which the conveying belt 251 alternates, that is, in the sub-scanning direction that is the circumferential direction. , Plus and minus are alternately charged in a band shape with a predetermined width. When the sheet 242 is fed onto the conveyance belt 251 charged alternately with plus and minus, the sheet 242 is attracted to the conveyance belt 251, and the sheet 242 is conveyed in the sub scanning direction by the circumferential movement of the conveyance belt 251.

  Therefore, by driving the recording head 234 according to the image signal while moving the carriage 233, ink droplets are ejected onto the stopped paper 242 to record one line, and after the paper 242 is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 242 has reached the recording area, the recording operation is finished and the paper 242 is discharged onto the paper discharge tray 203.

  Thus, since the image forming apparatus includes the liquid discharge head according to the present invention as a recording head, stable droplet discharge characteristics can be obtained, and a high-quality image can be stably formed.

  The liquid discharge head according to the present invention can be similarly applied to a line type image forming apparatus.

1 Channel plate (first substrate)
2 Vibration plate member 3 Nozzle plate 4 Nozzle 6 Liquid chamber 8 Common liquid chamber 12 Piezoelectric layer 20 Support member (second substrate)
21 Concave portion 22 Backing portion 233 Carriage 234a, 234b Recording head

Claims (4)

A flow path member that forms a liquid chamber in which a plurality of nozzles that discharge droplets communicate with each other;
A diaphragm member forming at least one wall surface of the liquid chamber;
A piezoelectric member that is provided on a side surface of the diaphragm member opposite to the liquid chamber and displaces a viable region of the diaphragm member;
A support member joined directly or through the diaphragm member to the flow path member,
The support member is provided with a backing portion bonded to a surface opposite to the liquid chamber of the diaphragm member so as to face a partition between adjacent liquid chambers,
The width of the backing portion in the nozzle arrangement direction is wider than the width of the partition wall between the liquid chambers in the nozzle arrangement direction,
The width of the lining portion in the nozzle arrangement direction defines the width in the nozzle arrangement direction of the vibrating region of the diaphragm member.   The liquid ejection head according to claim 1, wherein the backing portion is formed of a base material of the support member.   The liquid ejection head according to claim 1, wherein the backing portion is formed of a film formed on a base material of the support member.   An image forming apparatus comprising the liquid discharge head according to claim 1.

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