Patent Publication Number: US-9421767-B2

Title: Liquid ejecting head and manufacturing method of liquid ejecting head

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The entire disclosure of Japanese Patent Application No: 2014-125059, filed Jun. 18, 2014 is expressly incorporated by reference herein in its entirety. 
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a liquid ejecting head which ejects a liquid within a pressure chamber from a nozzle which communicates with the pressure chamber, and a manufacturing method of the liquid ejecting head. 
     2. Related Art 
     A liquid ejecting apparatus is an apparatus which is provided with a liquid ejecting head and which ejects various liquids from an ejecting head. An image recording apparatus such as an ink jet printer or an ink jet plotter is an example of the liquid ejecting apparatus; however, recently liquid ejecting apparatuses are also being adapted for use in various manufacturing apparatuses, making use of the characteristic of being capable of causing minute amounts of a liquid to accurately land on predetermined positions. For example, the liquid ejecting apparatuses are being adapted for use in display manufacturing apparatuses which manufacture color filters of liquid crystal displays and the like, electrode forming apparatuses which form electrodes of organic electro-luminescence (EL) displays, face emission displays (FED), and the like, and chip manufacturing apparatuses which manufacture biochips (biochemical elements). In a recording head for an image recording apparatus, a liquid-state ink is ejected, and in a color material ejecting head for a display manufacturing apparatus, solutions of color materials for each of red (R), green (G), and blue (B) are ejected. In an electrode material ejecting head for an electrode forming apparatus, a liquid-state electrode material is ejected, and in a bio-organic matter ejecting head for a chip manufacturing apparatus, a solution of bio-organic matter is ejected. 
     A plurality of nozzles, pressure chambers, one of which is formed for each nozzle, and a reservoir which is shared by the plurality of pressure chambers (also referred to as a common liquid chamber or a manifold) are provided inside the liquid ejecting head described above. Supply paths, which are formed to be narrower than the pressure chambers and which serve as channel resistance in relation to the liquid which flows into the pressure chambers, are formed in locations which communicate the reservoir with each of the pressure chambers (for example, refer to JP-A-2014-034114). The liquid ejecting head is configured to generate pressure fluctuation (a pressure change) in the liquid within the pressure chambers by the driving of piezoelectric elements (actuators), and to eject the liquid from the nozzles using the pressure fluctuation. 
     However, in the liquid ejecting head described above, when the pressure fluctuation is generated in the liquid within the pressure chambers, there is a counterflow of a portion of the liquid from the pressure chamber side to the reservoir side through the supply path. Due to the counterflow of a portion of the liquid, it may not be possible to eject the liquid from the nozzles by efficiently using the pressure fluctuation caused by the piezoelectric elements. 
     SUMMARY 
     An advantage of some aspects of the invention is to provide a liquid ejecting head capable of efficiently ejecting a liquid, and a manufacturing method of the liquid ejecting head. 
     According to an aspect of the invention, a liquid ejecting head includes a nozzle which ejects a liquid a pressure chamber, a portion of which is partitioned by a flexible diaphragm and which communicates with the nozzle, an actuator which is laminated on an opposite side of the diaphragm from the pressure chamber and changes a pressure within the pressure chamber, and a reservoir which communicates with the pressure chamber, in which a valve mechanism is provided in a region which is distanced from a region in which the actuator of the diaphragm is laminated, and is configured to allow the liquid to flow from the reservoir side into the pressure chamber side while inhibiting the liquid from flowing out from the pressure chamber side to the reservoir side. 
     In this case, it is possible to efficiently transmit the pressure change within the pressure chamber to the nozzle side when the liquid is ejected from the nozzle. As a result, it is possible to efficiently eject the liquid from the nozzle. 
     In the above configuration, it is preferable that the valve mechanism includes an opening which communicates the reservoir with the pressure chamber, and a valve receiving body which is provided in a position to mutually face the opening in the reservoir side, and it is preferable that, when an internal pressure of the pressure chamber rises relatively, an edge of the opening is elastically displaced to the reservoir side and inhibits the liquid from flowing out. 
     In this case, it is possible to simplify the configuration of the valve mechanism. 
     In this case, it is preferable that the edge of the opening and the valve receiving body overlap each other as viewed from a center axial direction of the opening of the diaphragm. 
     In this case, it is possible to more reliably prevent the flowing out of the liquid to the reservoir side. 
     In the configurations described above, it is preferable that at least a portion of the reservoir is partitioned by a portion which functions as a damper which absorbs a pressure change of the liquid within the reservoir. 
     In this case, it is possible to absorb the pressure change which occurs when the liquid is supplied into the reservoir. 
     According to another aspect of the invention, in a manufacturing method of a liquid ejecting head which includes a nozzle which ejects a liquid, a pressure chamber, a portion of which is partitioned by a flexible diaphragm and which communicates with the nozzle, an actuator which is laminated on an opposite side of the diaphragm from the pressure chamber and changes a pressure within the pressure chamber, a reservoir which communicates with the pressure chamber, and a valve mechanism which is provided in a region which is distanced from a region in which the actuator of the diaphragm is laminated, the method includes forming an opening in a region which is distanced from a region of the diaphragm in which the actuator is laminated, forming a valve receiving body in a region which overlaps the opening of the diaphragm in the reservoir side to interpose a thin film therebetween, and removing at least the thin film between the opening and the valve receiving body. 
     In this case, it is possible to easily form the valve mechanism. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is a perspective diagram illustrating the configuration of a printer. 
         FIG. 2A  is a cross sectional diagram illustrating the configuration of a recording head. 
         FIG. 2B  is an enlarged diagram illustrating region IIB. 
         FIG. 3  is a cross sectional diagram taken along line III-III in  FIG. 2B . 
         FIGS. 4A and 4B  are schematic diagrams illustrating the operations of a valve mechanism. 
         FIGS. 5A to 5C  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism. 
         FIGS. 6A to 6C  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism. 
         FIGS. 7A and 7B  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism. 
         FIGS. 8A and 8B  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism. 
         FIG. 9A  is a cross sectional diagram illustrating the configuration of a recording head in a second embodiment. 
         FIG. 9B  is an enlarged diagram illustrating region IXB. 
         FIGS. 10A and 10B  are schematic diagrams illustrating the operations of a valve mechanism in the second embodiment. 
         FIGS. 11A to 11C  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism in the second embodiment. 
         FIGS. 12A to 12C  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism in the second embodiment. 
         FIGS. 13A and 13B  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism in the second embodiment. 
         FIG. 14  is a cross sectional diagram illustrating the configuration of a recording head in a third embodiment. 
         FIG. 15  is a cross sectional diagram illustrating the configuration of a recording head in a fourth embodiment. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, description will be given of the embodiments of the invention with reference to the attached drawings. Note that, in the embodiments described hereinafter, there are various limits as favorable embodiments of the invention; however, the scope of the invention is not limited thereto as long as there is no wording particularly limiting the invention in the description hereinafter. Hereinafter, an ink jet printer (hereinafter, a printer) with an ink jet recording head (hereinafter, a recording head), which is a type of the liquid ejecting head, mounted thereon will be described as an example of the liquid ejecting apparatus of the invention. 
     Description will be given of the configuration of a printer  1  with reference to  FIG. 1 . The printer  1  is an apparatus which performs recording of an image or the like by ejecting a liquid-state ink onto the surface of a recording medium  2  (a type of landing target) such as recording paper. The printer  1  is provided with a recording head  3 , a carriage  4 , a carriage moving mechanism  5 , a transport mechanism  6 , and the like. The recording head  3  is attached to the carriage  4 , the carriage moving mechanism  5  causes the carriage  4  to move in a main scanning direction, and the transport mechanism  6  conveys the recording medium  2  in a sub-scanning direction. Here, the ink is a type of the liquid in the invention, and is stored in ink cartridges  7  which serve as liquid storage sources (liquid supply sources). The ink cartridges  7  are detachably mounted to the recording head  3 . Note that, a configuration may be adopted in which ink cartridges are disposed on a main body side of a printer, and an ink is supplied from the ink cartridges to a recording head through ink supply tubes. 
     The carriage moving mechanism  5  described above is provided with a timing belt  8 . The timing belt  8  is driven by a pulse motor  9  such as a DC motor. Accordingly, when the pulse motor  9  operates, the carriage  4  is guided by a guide rod  10  which is provided to span across the printer  1 , and moves reciprocally in the main scanning direction (the width direction of the recording medium  2 ). 
       FIG. 2A  is a cross sectional diagram illustrating the configuration of the recording head  3 , and  FIG. 2B  is an enlarged diagram illustrating region IIB in  FIG. 2A .  FIG. 3  is a cross sectional diagram taken along line III-III in  FIG. 2B . Note that, in  FIGS. 2A and 2B , the configuration of the main portions corresponding to another nozzle row is omitted due to being laterally symmetrical with the depicted configuration. As illustrated in  FIG. 2A , the recording head  3  in the present embodiment is provided with a pressure generation unit  14  and a channel unit  15 , and is configured to be attached to a head case  16  in a state in which the members are laminated together. 
     The head case  16  is a box-shaped member formed of a synthetic resin, and a reservoir  17  (also referred to as a common liquid chamber or a manifold) which supplies the ink to a plurality of pressure chambers  19  is formed inside the head case  16 . The ink which flows from the ink cartridges  7  into the recording head  3  is stored in the reservoir  17 . The reservoir  17  of the present embodiment is formed in the head case  16  with the bottom of the reservoir  17  in an open state, and is partitioned by the inner wall surfaces of the head case  16  and the top surface of a protective substrate (described later). The reservoir  17  is partitioned by a portion (a compliance portion) which functions as a damper which absorbs a pressure change of the ink within the reservoir  17 . In the present embodiment, the compliance portion is formed by an opening portion of the reservoir  17  to the side surfaces of the head case  16 , and sealing the opening with a flexible compliance sheet  18 . Note that, the compliance sheet  18  is formed of a hard substrate and film material laminated thereon, and is joined to the head case  16  from the film material side. A portion of the compliance sheet  18  which is formed by removing a portion of the substrate and leaving only the film material forms the compliance portion. Using the compliance portion, it is possible to absorb changes in pressure which occur when the ink is supplied into the reservoir  17 . 
     The pressure generation unit  14  forms a unit by a pressure chamber forming substrate  20  which forms the pressure chamber  19 , a diaphragm  24 , a piezoelectric element  26  (a type of actuator (pressure generating unit)), the protective substrate  27 , and the like being laminated together. The pressure chamber forming substrate  20  is formed of a silicon single crystal substrate, for example, and the plurality of pressure chambers  19  are formed to correspond to each nozzle  40  of a nozzle plate  39 . In the present embodiment, two rows of the nozzles  40  are formed on the nozzle plate  39 , and thus, there are two rows of the pressure chambers  19  corresponding to the respective nozzle rows formed on the pressure chamber forming substrate  20 . The pressure chamber  19  is a hollow portion which is long in the direction perpendicular to the direction in which the nozzles  40  are lined up, and extend from a position corresponding to the nozzle  40  to a position corresponding to the reservoir  17  at substantially the same width. 
     The diaphragm  24  (a type of flexible elastic film) is formed on the top surface of the pressure chamber forming substrate  20  (the surface of the opposite side from the joining surface with a communication substrate  41 ) in a state in which the diaphragm  24  seals the opening in the top portion of the pressure chamber  19 . In other words, the top surface of the pressure chamber  19  is partitioned by the diaphragm  24 . For example, the diaphragm  24  is formed of silicon dioxide which is approximately 1 μm thick. As illustrated in  FIG. 2B , a plurality of openings  23  which penetrate the diaphragm  24  in the plate thickness direction thereof are formed in the end portion of the reservoir  17  side of the diaphragm  24  to correspond to each of the pressure chambers  19 . The opening  23  is a portion which forms a valve mechanism  21 , and detailed description will be given later. An insulating film  25  formed of zirconium oxide, for example, is formed in a region on top of the diaphragm  24  and distanced from the valve mechanism  21 . Specifically, as illustrated in  FIG. 2B , the insulating film  25  is formed in a region in which the piezoelectric element  26  is laminated and in the periphery of a valve space  22  in which the valve mechanism  21  is formed so as to avoid the valve mechanism  21 . The piezoelectric elements  26  are formed in positions corresponding to each of the pressure chambers  19  on the insulating film  25 . 
     The piezoelectric element  26  of the present embodiment is a so-called flexure mode piezoelectric element  26 . As illustrated in  FIG. 2B , the piezoelectric element  26  is formed by the sequential lamination of a bottom electrode film  29 , a piezoelectric layer  30 , and a top electrode film  31  on the insulating film  25  of the nozzle  40  side. In the present embodiment, whereas the bottom electrode film  29  is provided independently for each of the pressure chambers  19 , the top electrode film  31  is provided continually across the plurality of pressure chambers  19 . Therefore, the bottom electrode films  29  are individual electrodes for each of the pressure chambers  19 , and the top electrode film  31  is a common electrode which is shared by the pressure chambers  19 . The region in which the piezoelectric layer  30  is interposed between the bottom electrode film  29  and the top electrode film  31  is an active portion in which piezoelectric deformation occurs due to the application of a voltage between both electrodes. Note that, the bottom electrode film may be provided as a common electrode by forming the bottom electrode film continually across the plurality of pressure chambers, and the top electrode film may be provided as individual electrodes by providing the top electrode film independently for each of the pressure chambers. Various metals such as indium (Ir), platinum (Pt), titanium (Ti), tungsten (W), tantalum (Ta), and molybdenum (Mo), an alloy thereof, or the like may be used as the top electrode film  31  and the bottom electrode film  29 . LaNiO 3  is an example of an alloy electrode. A ferroelectric material such as lead zirconate titanate (PZT), a relaxor ferroelectric body obtained by adding a metal such as niobium, nickel, magnesium, bismuth or yttrium to the ferroelectric material, or the like may be used as the piezoelectric layer  30 . It is also possible to use a lead free material such as barium titanate as the piezoelectric layer  30 . 
     The bottom electrode film  29 , the piezoelectric layer  30 , and the top electrode film  31  are formed to surround the valve mechanism  21 , even in the periphery of the valve mechanism  21 . Accordingly, the valve space  22  is formed in the periphery of the valve mechanism  21  by partitioning. Since a plurality of the valve mechanisms  21  are formed to correspond to the plurality of pressure chambers  19 , a plurality of the valve spaces  22  are also formed to correspond thereto. Specifically, as illustrated in  FIG. 2B , the top electrode film  31  and the bottom electrode film  29 , which are electrically isolated from the top electrode film  31  and the bottom electrode film  29  of the piezoelectric element  26 , are formed in a position shifted closer to the valve mechanism  21  side than the piezoelectric element  26  to interpose the piezoelectric layer  30  which extends from the piezoelectric element  26 . The bottom electrode film  29 , the piezoelectric layer  30 , and the top electrode film  31  are also laminated on the opposite side from the piezoelectric element to interpose the valve mechanism  21 , and on both sides of the valve mechanism  21  in the nozzle row direction. Accordingly, the valve space  22  is formed in the periphery of the valve mechanism  21 . Note that, a voltage is not applied to the top electrode film  31  and the bottom electrode film  29  of the portions which partition the periphery of the valve space  22 . Therefore, the piezoelectric layer  30  interposed therebetween will not warp through intentional deformation. 
     As illustrated in  FIG. 2A , a common metal layer  33  which continues across the plurality of pressure chambers  19  is laminated in an end portion region of the piezoelectric element  26  in the longitudinal direction (the direction perpendicular to the nozzle row direction). The common metal layer  33  is formed of gold (Au), for example, and, as illustrated in  FIG. 2B , and is laminated on top of the top electrode film  31  via an adhesion layer  34  (a thin film in the invention) which is formed of titanium, nickel, chrome, an alloy thereof, or the like. The common metal layer  33  and the adhesion layer  34  of the present embodiment are formed on both end portions of the piezoelectric element  26  in the longitudinal direction, and in the periphery of the valve space  22 . The common metal layer  33  which is formed on the end portion of the nozzle  40  side of the piezoelectric element  26  is electrically connected to the top electrode film  31  and the bottom electrode film  29 , and, as illustrated in  FIG. 2A , extends past the end portion of the pressure chamber  19  (in detail, the top opening edge of the space which forms the pressure chamber) to a terminal region. The common metal layer  33  is electrically connected to electrode terminals of a wiring member (not shown) such as a flexible cable in the terminal region. Only the common metal layer  33  is partially formed in a position relative to the opening  23  of the diaphragm  24  within the valve space  22 . The portion of the common metal layer  33  is the portion which serves as a valve receiving body  32  of the valve mechanism  21 . Detailed description of the valve receiving body  32  will be given later. 
     The protective substrate  27  is disposed on top of the common metal layer  33 . Specifically, layers of the diaphragm  24 , the insulating film  25 , the bottom electrode film  29 , the piezoelectric layer  30 , the top electrode film  31 , the adhesion layer  34 , and the common metal layer  33  are laminated on the pressure chamber forming substrate  20 , and the bottom surface (the surface of the common metal layer  33  side) of the protective substrate  27  at which the plate thickness is the greatest is joined to the top of the common metal layer  33 . Note that, the protective substrate  27  is made of, for example, glass, ceramic material, silicon single crystal substrate, metal, or a hard member of synthetic resin or the like. A concave portion  37 , which is formed at a size at which the driving of the piezoelectric element  26  is not inhibited, is formed in a region of the protective substrate  27  facing the active portion of the piezoelectric element  26 . In the protective substrate  27 , a plurality of communication paths  28 , which penetrate the protective substrate  27  in the plate thickness direction, are formed to correspond to the plurality of lined up pressure chambers  19  in positions corresponding to the valve spaces  22 . The top end of the communication path  28  communicates with the reservoir  17 , and the bottom end of the communication path  28  communicates with the pressure chamber  19  via the valve mechanism  21 . Unlike the supply path of the related art which communicates between the reservoir and the pressure chamber, the communication path  28  is configured to reduce the channel resistance as much as possible. In other words, the supply path of the related art is designed to have a predetermined channel resistance by being formed with a narrower width than the pressure chamber; however, in the recording head  3  of the present embodiment, since the communication path  28  includes the valve mechanism  21 , it is not necessary to provide the channel resistance, and the communication path  28  is formed such that, for example, the cross-sectional area of the communication path  28  is greater than or equal to the cross-sectional area of the pressure chamber  19 . Note that, with regard to the communication path  28 , it is also possible to configure the communication path  28  as a channel which is shared by the pressure chambers as a portion of the reservoir without partitioning the communication path  28  for each pressure chamber. 
     The channel unit  15  includes the communication substrate  41  which is joined to the bottom surface of the pressure chamber forming substrate  20  and the nozzle plate  39  which is joined to the bottom surface of the communication substrate  41 . A plurality of the nozzles  40  are open in the nozzle plate  39  in a straight line formation (row formation). The plurality of lined up nozzles  40  are provided at an equal interval along the sub-scanning direction which is perpendicular to the main scanning direction from the nozzle  40  of one end side to the nozzle  40  of the other end side at a pitch (for example, 180 dpi) corresponding to the dot formation density. In the present embodiment, two nozzle rows are formed on the nozzle plate  39 . The communication substrate  41  partitions the bottom surface of the pressure chamber  19  by sealing the bottom opening of the pressure chamber  19 . Nozzle communication paths  42  which communicate between the nozzles  40  and the pressure chambers  19  are provided in the communication substrate  41  to line up in a straight line formation at the same pitch as the nozzles  40 . Note that, the nozzle  40  and the nozzle communication path  42  are formed on the end portion of the opposite side from the valve mechanism  21  side of the pressure chamber  19  in the longitudinal direction of the pressure chamber  19 . The head case  16  is joined to the top surface of the communication substrate  41  closer to the outside than the pressure generation unit  14  in a state of housing the pressure generation unit  14  therein. 
     Next, description will be given of the valve mechanism  21 . As described above, the valve mechanism  21  is provided in a region which is distanced from the region in which the piezoelectric element  26  of the diaphragm  24  is laminated, and is configured to allow the ink to flow from the reservoir  17  side into the pressure chamber  19  side while inhibiting the ink from flowing out from the pressure chamber  19  side to the reservoir  17  side. Specifically, as illustrated in  FIG. 2B , the valve mechanism  21  includes an opening  23  and a valve receiving body  32 . The opening  23  is formed in the diaphragm  24  in the valve space  22  and communicates the reservoir  17  with the pressure chamber  19  via the communication path  28  and the valve space  22 , and the valve receiving body  32  is provided in a position to face the opening  23  mutually in the reservoir  17  side and is formed of a portion of the common metal layer  33 . As described above, since the diaphragm  24  is flexible, the edge of the opening  23  of the diaphragm  24  functions as a valve body which is displaced according to variation in the internal pressure of the pressure chamber  19 . As illustrated in  FIG. 3 , the valve receiving body  32  of the present embodiment is formed in the shape of a bridge which extends in the nozzle row direction in the center of the valve space  22  and functions as a valve seat in relation to the edge of the opening  23 . The opening  23  of the diaphragm  24  is formed to be a size smaller than the valve receiving body  32 . In other words, in plan view (as viewed from a center axial direction of the opening  23  of the diaphragm  24 ), the edge of the opening  23  of the diaphragm  24  and the valve receiving body  32  are formed so as to overlap each other. As illustrated in  FIG. 2B , the portion of the valve receiving body  32  which overlaps the diaphragm  24 , that is, the edge of the valve receiving body  32  is depressed to the reservoir  17  side by the thickness of the diaphragm  24 , and is distanced from the diaphragm  24  by leaving a gap equal to the thickness of the adhesion layer  34  in a state in which the diaphragm  24  is not displaced (a non-flexing state). 
     In the valve mechanism  21  which is formed in this manner, when the internal pressure of the pressure chamber  19  rises relatively due to the driving of the piezoelectric element  26 , as illustrated in  FIG. 4A , the edge of the opening  23  of the diaphragm  24  is elastically displaced to the reservoir  17  side, abuts the valve receiving body  32 , and enters an open-valve state, thereby inhibiting the flowing out of the ink from the pressure chamber  19  side to the reservoir  17  side. Meanwhile, when the internal pressure of the pressure chamber  19  drops relatively due to the driving of the piezoelectric element  26 , as illustrated in  FIG. 4B , the edge of the opening  23  of the diaphragm  24  is elastically displaced to the pressure chamber  19  side, releases the abutting state between the diaphragm  24  and the valve receiving body  32  (the edge of the opening  23  is distanced from the valve receiving body  32 ), and enters a closed-valve state. Accordingly, the flowing of the ink from the reservoir  17  side into the pressure chamber  19  side is allowed. In other words, due to providing the valve mechanism  21 , the channel resistance in relation to the ink which flows out from the pressure chamber  19  side to the reservoir  17  side is greater than the channel resistance in relation to the ink which flows from the reservoir  17  side into the pressure chamber  19  side. 
     Here, with regard to the dimensions of the opening  23 , it is preferable to satisfy the following expression (1) when wa is the width of the valve receiving body  32  (the dimension in a direction perpendicular to the extending direction of the valve receiving body  32 ) and wb is the width of the opening  23  (the dimension in a direction perpendicular to the extending direction of the valve receiving body  32 ).
 
wa≧wb  (1)
 
     Accordingly, when the internal pressure of the pressure chamber  19  rises relatively, it is possible to more reliably inhibit the flowing out of the ink from the pressure chamber  19  side to the reservoir  17  side. 
     It is preferable to satisfy the following expression (2) when ha is the length of the valve receiving body  32  (the dimension in the extending direction of the valve receiving body  32 ), and hb is the length of the opening  23  (the dimension in the extending direction of the valve receiving body  32 ).
 
ha≧hb  (2)
 
     Accordingly, when the internal pressure of the pressure chamber  19  rises relatively, it is possible to more reliably inhibit the flowing out of the ink from the pressure chamber  19  side to the reservoir  17  side. 
     In the recording head  3  which is formed in this manner, the pressure in the pressure chamber  19  is caused to drop by driving the piezoelectric element  26 , and the ink is taken into the pressure chamber  19  from the reservoir  17  via the valve mechanism  21 . Subsequently, the pressure in the pressure chamber  19  is raised by driving the piezoelectric element  26 . Using the rise in pressure, the ink within the pressure chamber  19  is ejected from the nozzle  40  via the nozzle communication path  42 . 
     In the recording head  3  in the invention, since the valve mechanism  21  is provided between the reservoir  17  and the pressure chamber  19 , it is possible to suppress the counterflow of the ink to the reservoir  17  side when the pressure in the pressure chamber  19  is raised. Accordingly, it is possible to efficiently transmit the rise in pressure in the pressure chamber  19  to the nozzle  40  side, and it is possible to efficiently eject the ink from the nozzle  40 . As a result, it is possible to reduce the pressure change which is generated by the piezoelectric element  26  which is necessary to eject a fixed amount of the ink. Accordingly, it is possible to reduce the size of the piezoelectric element  26  (the active portion), and thus it is possible to reduce the size of the recording head  3 . By reducing the size of the piezoelectric elements  26 , it is possible to reduce the pitch at which the piezoelectric elements  26  are provided to line up. In other words, it is possible to reduce the pitch at which the nozzles  40  are provided to line up. Accordingly, since it is possible to reduce the pitch at which the nozzles are formed, higher definition printing becomes possible, and it is possible to improve the quality of the printing. It is possible to lower the voltage which is applied to the piezoelectric element  26 , and the reliability of the recording head  3  is improved. 
     In the related art, the supply path which acts as a channel resistance and has a narrower width than the pressure chamber is formed between the reservoir and the pressure chamber; however, since it is not necessary to form such a supply path, it is possible to further reduce the size of the recording head  3 . Since the pressure change which is generated in the pressure chamber  19  during the ejection of the ink does not easily transmit to the reservoir  17  side due to the valve mechanism  21 , it is possible to reduce the area of the portion (the compliance portion) which is provided in the reservoir  17  and which functions as a damper which absorbs the pressure change. In other words, in the compliance portion, an area may be secured at which it is possible to suppress the pressure change within the reservoir  17  which is generated when the ink within the reservoir  17  is supplied to a range which causes no problems in the specification of the product, and it is possible to reduce the size of the compliance portion as much as possible within the range. Accordingly, it is possible to further reduce the size of the recording head  3 . Since the valve mechanism  21  is formed of the opening  23  of the diaphragm  24  and the valve receiving body  32  which is provided in a position to face the opening  23  mutually in the reservoir  17  side, it is possible to simplify the configuration of the valve mechanism  21 . Since the edge of the opening  23  and the valve receiving body  32  overlap each other as viewed from a center axial direction of the opening  23  of the diaphragm  24 , it is possible to more reliably prevent the flowing out of the ink to the reservoir  17  side. 
     Next, description will be given of the manufacturing method of the recording head  3  which includes the valve mechanism  21  described above.  FIGS. 5A to 8B  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism  21 . In the present embodiment, rises in the manufacturing cost caused by an increase in the number of processes are suppressed by sharing the majority of the processes of forming the valve mechanism  21  with the processes of forming the diaphragm, the piezoelectric element, and the common metal layer of the related art. Note that, in the following manufacturing method, description is given with the main focus on the valve mechanism  21 . 
     Specifically, first, as illustrated in  FIG. 5A , the diaphragm  24  and the insulating film  25  are laminated, in this order, on the pressure chamber forming substrate  20  (in detail, the substrate which serves as the pressure chamber forming substrate  20 , for example, a silicon single crystal substrate). As illustrated in  FIG. 5B , the bottom electrode film  29  is formed as a film on the insulating film  25 , and a portion which serves as the common electrode of the piezoelectric element  26  is patterned using wet etching or dry etching. Next, as illustrated in  FIG. 5C , the piezoelectric layer  30  is formed as a film, a portion of the piezoelectric layer  30  is removed using wet etching or dry etching such that portions which serve as the piezoelectric elements  26  and the periphery of a portion which serves as the valve space  22  remain. Subsequently, as illustrated in  FIG. 6A , the top electrode film  31  is formed as a film, a portion of the top electrode film  31  is removed using wet etching or dry etching such that portions which serve as individual electrodes of the piezoelectric elements  26  and the periphery of a portion which serves as the valve space  22  remain. Accordingly, the piezoelectric element  26  is formed. 
     If the piezoelectric element  26  is formed, as illustrated in  FIG. 6B , the insulating film  25  and the bottom electrode film  29  of a portion which serves as the valve space  22  which is formed in a region distanced from the region in which the piezoelectric element  26  is laminated are removed using wet etching or dry etching. Next, as illustrated in  FIG. 6C , the opening  23  is formed by partially removing the diaphragm  24  within the valve space  22  using wet etching or dry etching and penetrating the diaphragm  24  in the thickness direction. Here, the opening  23  of the diaphragm  24  is formed smaller than the portion of the insulating film  25  and the bottom electrode film  29  within the valve space  22  which is removed. Subsequently, as illustrated in  FIG. 7A , the adhesion layer  34  and the common metal layer  33  are formed as a film in this order, portions of the adhesion layer  34  and the common metal layer  33  are removed using wet etching or dry etching such that both end portions of the piezoelectric element  26  in the longitudinal direction, the periphery of the valve space  22 , and the portion which serves as the valve receiving body  32  remain. Accordingly, the valve receiving body  32  is formed in a region of the diaphragm  24  which overlaps the opening  23  in the reservoir  17  side so as to interpose the adhesion layer  34 . Here, the valve receiving body  32  and the adhesion layer  34  on which the valve receiving body  32  is laminated are patterned to be slightly larger than the opening  23  so as to cover the opening  23  of the diaphragm  24 . Next, as illustrated in  FIG. 7B , the protective substrate  27  is joined to the common metal layer  33  from the top surface side using an adhesive or the like. Accordingly, the communication path  28  of the protective substrate  27  and the valve space  22  are communicated with each other. Note that, a protective film  43  is bonded to a surface of an opposite side of the protective substrate  27  from the surface which is joined to the common metal layer  33 . 
     If the protective substrate  27  is joined, as illustrated in  FIG. 8A , the pressure chamber  19  is formed by wet etching the substrate which serves as the pressure chamber forming substrate  20  from the surface of the opposite side from the diaphragm  24 . At this time, since the protective film  43  is bonded to the protective substrate  27 , the etching liquid entering the piezoelectric element  26  side from the protective substrate  27  side is suppressed. The protective film  43  is removed after the wet etching which forms the pressure chamber  19  ends. Subsequently, as illustrated in  FIG. 8B , at least the adhesion layer  34  between the opening  23  and the valve receiving body  32  is removed by wet etching using an etching liquid which removes only the adhesion layer  34 . Accordingly, a gap is formed between the valve receiving body  32  and the diaphragm  24 . In this manner, the pressure generation unit  14  which includes the valve mechanism  21  is formed. Finally, the recording head  3  which includes the valve mechanism  21  is created by joining the channel unit  15  to the pressure generation unit  14  from the bottom surface side (the pressure chamber forming substrate  20  side), and by joining the head case  16  to the pressure generation unit  14  from the top surface side (the protective substrate  27  side). 
     In this manner, since the manufacturing method of the recording head  3  in the invention includes a process in which the opening  23  is formed in a region which is distanced from the region in which the piezoelectric element  26  of the diaphragm  24  is laminated, a process in which the valve receiving body  32  is formed to interpose the adhesion layer  34  in a region which overlaps the opening  23  in the reservoir  17  side of the diaphragm  24 , and a process in which at least the adhesion layer  34  between the opening  23  and the valve receiving body  32  is removed, it is possible to easily form the valve mechanism  21 . 
     Incidentally, the configuration in which the valve mechanism is provided in a region which is distanced from the region which is between the reservoir and the pressure chamber and in which the piezoelectric element of the diaphragm of the recording head is laminated is not limited to the embodiment described above. In the second embodiment illustrated in  FIGS. 9A and 9B , the valve mechanism  46  is formed on the bottom side (the opposite side from a pressure chamber  19 ′) of a communication substrate  41 ′. 
       FIG. 9A  is a cross sectional diagram illustrating the configuration of a recording head  3 ′ in the second embodiment, and  FIG. 9B  is an enlarged diagram illustrating region IXB in  FIG. 9A . As illustrated in  FIG. 9A , the recording head  3 ′ in the present embodiment is also provided with a pressure generation unit  14 ′ and a channel unit  15 ′, and is configured to be attached to a head case  16 ′ in a state in which the members are laminated together. 
     As opposed to in the first embodiment described above, no reservoir is formed on the inner portion of the head case  16 ′ of the present embodiment, and, as illustrated in  FIG. 9A , a liquid supply path  44  which supplies the ink to the reservoir  45  is formed on the inner portion of the head case  16 ′. The ink which flows from the ink cartridges  7  into the recording head  3 ′ flows into the reservoir  45  which is positioned below the head case  16 ′ via the liquid supply path  44 . 
     In the same manner as in the first embodiment described above, the pressure generation unit  14  forms a unit by a pressure chamber forming substrate  20 ′, a diaphragm  24 ′, a piezoelectric element  26 ′, a protective substrate  27 ′, and the like being laminated together; however, the valve mechanism is not provided. In other words, an opening is not provided in the diaphragm  24 ′ which partitions the top surface of the pressure chamber forming substrate  20 ′, and the valve space is not formed. Therefore, the opening of the top portion of the pressure chamber  19 ′ is sealed by the diaphragm  24 ′ without gaps. In other words, in the present embodiment, the piezoelectric element  26 ′ is formed on the diaphragm  24 ′ of the pressure chamber  19 ′ via an insulating film  25 ′, and a common metal layer  33 ′ is formed on both end portions in the longitudinal direction on the piezoelectric element  26 ′ via an adhesion layer (not shown). The protective substrate  27 ′ is joined onto the common metal layer  33 ′. 
     In addition to a nozzle plate  39 ′ and the communication substrate  41 ′, the channel unit  15 ′ of the present embodiment is provided with a reservoir part  48  in which the reservoir  45  is formed and the valve mechanism  46 . A nozzle communication path  42 ′ which communicates between the nozzle  40 ′ and the pressure chamber  19 ′ is formed in the communication substrate  41 ′ in the same manner as in the first embodiment. Additionally, a pressure chamber communication path  49  and a reservoir communication path  50  are formed in the communication substrate  41 ′ of the present embodiment. The pressure chamber communication path  49  is a channel which communicates between the reservoir  45  and the pressure chamber  19 ′, and is formed between the reservoir communication path  50  and the nozzle communication path  42 ′. The top end of the pressure chamber communication path  49  is open to the pressure chamber  19 ′ at the end portion of the opposite side from the nozzle communication path  42 ′ side of the pressure chamber  19 ′. The bottom end of the pressure chamber communication path  49  is open to the reservoir  45  at the end portion of the opposite side from the reservoir communication path  50  side. The reservoir communication path  50  is a channel which communicates between the liquid supply path  44  and the reservoir  45 , and is formed in a position corresponding to the liquid supply path  44 . Note that, the nozzle plate  39 ′ of the present embodiment is formed as small as possible, and is joined to the communication substrate  41 ′ closer to the inside thereof than the reservoir part  48 . 
     The reservoir part  48  is a substrate to which a compliance sheet  18 ′ is joined from below, and is joined to the bottom surface side of the communication substrate  41 ′ closer to the outside than the nozzle plate  39 ′. The reservoir  45  which supplies the ink to the plurality of pressure chambers is formed on the inner portion of the reservoir part  48 . The reservoir  45  is shaped such that the top and bottom are open (that it, has a shape penetrated in the thickness direction), and is formed by the top being sealed by the communication substrate  41 ′ (in detail, the communication substrate  41 ′ in which an elastic substrate  51 , an intermediary layer  52 , and a valve receiving body forming substrate  53  (described later) are laminated on the bottom surface side of the communication substrate  41 ′) and the bottom being sealed by the compliance sheet  18 ′. A portion (a compliance portion) which functions as a damper which absorbs a pressure change of the ink within the reservoir  45  is formed below the reservoir part  48  by the compliance sheet  18 ′. According to the present embodiment, in the same manner as the embodiment described above, it is possible to reduce the area of the portion (the compliance portion) which functions as a damper. Note that, the reservoir part  48  may be formed of a single substrate, and may be formed by laminating a plurality of substrates together. For example, when the reservoir part is formed of a plurality of substrates, it is possible to form the compliance portion in the middle of the reservoir part by inserting a compliance sheet in the middle of the plurality of substrates. 
     As illustrated in  FIG. 9B , the elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53  are laminated between the reservoir part  48  and the communication substrate  41 ′. Specifically, the elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53  are laminated in order from the bottom surface side of the communication substrate  41 ′. The elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53  are layers for forming the valve mechanism  46 . The elastic substrate  51  is a flexible substrate (a film), and is formed of silicon dioxide which is approximately 1 μm thick, for example. The intermediary layer  52  is formed of titanium, nickel, chrome, an alloy thereof, or the like, and improves the adherence (adhesion) between the elastic substrate  51  and the valve receiving body forming substrate  53 . Additionally, it is possible to use a resin, an adhesive, or the like as the intermediary layer  52 . The valve receiving body forming substrate  53  is formed of a metal such as gold (Au), for example. Note that, an opening (omitted from the drawing) for communicating between the reservoir communication path  50  and the reservoir  45  is formed in a location corresponding to the reservoir communication path  50  in the elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53 . 
     As illustrated in  FIG. 9B , the valve mechanism  46  is formed between the pressure chamber communication path  49  and the reservoir  45 . Specifically, the valve mechanism  46  includes an opening  54  and a valve receiving body  55 . The opening  54  is formed in the elastic substrate  51  and communicates the pressure chamber  19 ′ (the pressure chamber communication path  49 ) with the reservoir  45 , and the valve receiving body  55  is provided in a position to mutually face the opening  54  in the reservoir  45  side and is formed of the valve receiving body forming substrate  53 . The valve receiving body  55  is provided within a valve space  47  which is formed by removing the valve receiving body forming substrate  53  of a region corresponding to the pressure chamber communication path  49 . In other words, the valve receiving body  55  is formed by penetrating a portion of a region corresponding to the pressure chamber communication path  49  of the valve receiving body forming substrate  53  other than the portion corresponding to the opening  54  of the elastic substrate  51  in the plate thickness direction. In the same manner as in the first embodiment described above, the valve receiving body  55  of the present embodiment is formed in the center of the valve space  47  to extend in the nozzle row direction. The opening  54  of the elastic substrate  51  is formed a size smaller than the valve receiving body  55 . In other words, in plan view (as viewed from a center axial direction of the opening  54  of the elastic substrate  51 ), the edge of the opening  54  of the elastic substrate  51  is formed to overlap the valve receiving body  55 . Note that, the valve receiving body  55  and the elastic substrate  51  are distanced by leaving a gap equal to the thickness of the intermediary layer  52  in a state in which the elastic substrate  51  is not displaced (a non-flexing state). Note that, since the other configuration is the same as that of the first embodiment described above, description thereof will be omitted. 
     Even with the valve mechanism  46  of the present embodiment, it is possible to allow the ink to flow from the reservoir  45  side into the pressure chamber  19 ′ side while inhibiting the ink from flowing out from the pressure chamber  19 ′ side to the reservoir  45  side. In other words, when the internal pressure of the pressure chamber  19 ′ rises relatively due to the driving of the piezoelectric element  26 ′, as illustrated in  FIG. 10A , the edge of the opening  54  of the elastic substrate  51  is elastically displaced to the reservoir  45  side, abuts the valve receiving body  55 , and enters a closed-valve state, thereby inhibiting the flowing out of the ink from the pressure chamber  19 ′ side to the reservoir  45  side. Meanwhile, when the internal pressure of the pressure chamber  19 ′ drops relatively due to the driving of the piezoelectric element  26 ′, as illustrated in  FIG. 10B , the edge of the opening  54  of the elastic substrate  51  is elastically displaced to the pressure chamber  19 ′ side, valve opens to release the space between the elastic substrate  51  and the valve receiving body  55 , and allows the flowing of the ink from the reservoir  45  side into the pressure chamber  19 ′ side. In other words, due to providing the valve mechanism  46 , the channel resistance in relation to the ink which flows out from the pressure chamber  19 ′ side to the reservoir  45  side is greater than the channel resistance in relation to the ink which flows from the reservoir  45  side into the pressure chamber  19 ′ side. 
     Note that, even in the present embodiment, it is preferable to satisfy the following expression (1) when wa is the width of the valve receiving body  55  (the dimension in a direction perpendicular to the extending direction of the valve receiving body  55 ) and wb is the width of the opening  54  (the dimension in a direction perpendicular to the extending direction of the valve receiving body  55 ).
 
wa≧wb  (1)
 
     Accordingly, when the internal pressure of the pressure chamber  19 ′ rises relatively, it is possible to more reliably inhibit the flowing out of the ink from the pressure chamber  19 ′ side to the reservoir  45  side. 
     It is preferable to satisfy the following expression (2) when ha is the length of the valve receiving body  55  (the dimension in the extending direction of the valve receiving body  55 ), and hb is the length of the opening  54  (the dimension in the extending direction of the valve receiving body  55 ).
 
ha≧hb  (2)
 
     Accordingly, when the internal pressure of the pressure chamber  19 ′ rises relatively, it is possible to more reliably inhibit the flowing out of the ink from the pressure chamber  19 ′ side to the reservoir  45  side. 
     In the recording head  3 ′ of the present embodiment, since the valve mechanism  46  is provided between the reservoir  45  and the pressure chamber  19 ′, it is possible to suppress the counterflow of the ink to the reservoir  45  side when the pressure in the pressure chamber  19 ′ is raised. Accordingly, it is possible to efficiently transmit the rise in pressure in the pressure chamber  19 ′ to the nozzle  40  side, and it is possible to efficiently eject the ink from the nozzle  40 . As a result, it is possible to reduce the pressure change which is generated by the piezoelectric element  26 ′ which is necessary to eject a fixed amount of the ink. Accordingly, it is possible to reduce the size of the piezoelectric element  26 ′ (the active portion), and thus it is possible to reduce the size of the recording head  3 ′. By reducing the size of the piezoelectric elements  26 ′, it is possible to reduce the pitch at which the piezoelectric elements  26 ′ are provided to line up. In other words, it is possible to reduce the pitch at which the nozzles  40 ′ are provided to line up. Accordingly, higher definition printing becomes possible, and it is possible to improve the quality of the printing. It is possible to lower the voltage which is applied to the piezoelectric element  26 ′, and the reliability of the recording head  3 ′ is improved. 
     Even in the present embodiment, since it is not necessary to form the supply path between the reservoir and the pressure chamber as in the related art, it is possible to further reduce the size of the recording head  3 ′. Since the pressure change which is generated in the pressure chamber  19 ′ during the ejection of the ink does not easily transmit to the reservoir  45  side due to the valve mechanism  46 , it is possible to reduce the area of the portion (the compliance portion) which is provided in the reservoir  45  and which functions as a damper which absorbs the pressure change. Accordingly, it is possible to further reduce the size of the recording head  3 ′. Since the valve mechanism  46  is formed of the opening  54  of the elastic substrate  51  and the valve receiving body  55  which is provided in a position to face the opening  54  mutually in the reservoir  45  side, it is possible to simplify the configuration of the valve mechanism  46 . Since the edge of the opening  54  and the valve receiving body  55  overlap each other as viewed from a center axial direction of the opening  54  of the elastic substrate  51 , it is possible to more reliably prevent the flowing out of the ink to the reservoir  45  side. 
     Next, description will be given of the manufacturing method of the recording head  3 ′ which includes the valve mechanism  46  of the present embodiment.  FIGS. 11A and 13B  are diagrams of a state transition in cross section which illustrate the manufacturing process of the valve mechanism  46  in the present embodiment. Note that, in the following manufacturing method, description is given with a main focus on the valve mechanism  46 . 
     As illustrated in  FIG. 11A , the elastic substrate  51  is formed as a film on the bottom surface of the communication substrate  41 ′ (in detail, the substrate which serves as the communication substrate  41 ′, for example, a silicon single crystal substrate). Next, as illustrated in  FIG. 11B , the opening  54  is formed by removing a portion of the elastic substrate  51  using wet etching or dry etching. As illustrated in  FIG. 11C , the intermediary layer  52  is formed as a film on the bottom surface side of the communication substrate  41 ′ on which the elastic substrate  51  is laminated. As illustrated in  FIG. 12A , the valve receiving body forming substrate  53  is formed as a film on the bottom surface side of the intermediary layer  52 . 
     If the valve receiving body forming substrate  53  is laminated on the communication substrate  41 ′ via the intermediary layer  52 , the communication substrate  41 ′ is etched using the BOSCH method or the like, and, as illustrated in  FIG. 12B , the pressure chamber communication path  49  is formed. Note that, at this time, the nozzle communication path  42 ′, the reservoir communication path  50 , and the like are also formed at the same time. As illustrated in  FIG. 12C , the valve receiving body  55  and the valve space  47  are formed by removing a portion of the valve receiving body forming substrate  53  and the intermediary layer  52  from the bottom surface side using wet etching or dry etching. Subsequently, as illustrated in  FIG. 13A , at least the intermediary layer  52  between the opening  54  and the valve receiving body  55  is removed by wet etching using an etching liquid which removes only the intermediary layer  52 . Accordingly, the valve receiving body  55  is separated from the elastic substrate  51 . In this manner, the valve mechanism  46  is formed. As illustrated in  FIG. 13B , if the valve mechanism  46  is formed, the reservoir part  48  is joined to the valve receiving body forming substrate  53  from the bottom surface side. The nozzle plate  39 ′ is joined to the communication substrate  41 ′ from the bottom surface side, and the channel unit  15 ′ is created. Finally, the recording head  3 ′ which includes the valve mechanism  46  is created by joining the pressure generation unit  14 ′ and the head case  16 ′ to the channel unit  15 ′ from the top surface side. 
     Note that, in the second embodiment described above, the communication substrate is formed using a single substrate; however, it is also possible to form the communication substrate using a plurality of substrates. When the communication substrate is formed using a plurality of substrates, the valve mechanism may be formed on the bottom surface of the communication substrate, and may be formed in the middle of the communication substrate (that is, the pressure chamber communication path) in the plate thickness direction. When the valve mechanism is formed in the middle of the pressure chamber communication path in the plate thickness direction, the elastic substrate, the intermediary layer, and the valve receiving body forming substrate are laminated between vertically adjacent substrates of the plurality of substrates which form the communication substrate. 
     In the first and second embodiments, in a state in which the diaphragm or the elastic substrate are not displaced, the diaphragm or the elastic substrate of the edge of the opening is distanced from the valve receiving body; however, the invention is not limited thereto, and it is also possible to configure the diaphragm or the elastic substrate not to be distanced. That is, when the internal pressure of the pressure chamber drops relatively, the diaphragm or the elastic substrate of the edge of the opening may be displaced to the pressure chamber side, and may permit the flowing in of the ink from the reservoir side to the pressure chamber side. 
     In the first and second embodiments described above, the manufacturing process of the valve mechanism is described as the manufacturing method of the recording head; however, the invention is not limited thereto. In the manufacturing method described above, it is possible to use the manufacturing process of the valve mechanism as the manufacturing method of the valve mechanism. For example, it is possible to adapt the manufacturing process of the valve mechanism for the manufacturing method of a valve mechanism which is provided in something other than the recording head described above. 
     Incidentally, in the first embodiment described above, the communication substrate  41  is laminated between the pressure chamber forming substrate  20  and the nozzle plate  39 ; however, the invention is not limited thereto. In the third embodiment illustrated in  FIG. 14 , the communication substrate is not provided, and the nozzle plate  39  is joined to the pressure chamber forming substrate  20 . In other words, the opening of the bottom portion of the pressure chamber  19  is sealed by the nozzle plate  39 . The nozzle  40  communicates directly with the end portion of the opposite side from the valve mechanism  21  side of the pressure chamber  19  in the longitudinal direction of the pressure chamber  19 . The head case  16  is joined to the nozzle plate  39  further outside than the pressure generation unit  14  of the top surface of the nozzle plate  39 . Note that, since the other configuration is the same as that of the first embodiment described above, description thereof will be omitted. 
     In this manner, since the communication substrate is not provided in the present embodiment, the number of manufacturing processes of the recording head  3  is reduced. Accordingly, it is possible to reduce manufacturing costs. It is possible to reduce the thickness of the recording head  3  by an amount equal to the thickness of the communication substrate, and it is possible to further reduce the size of the recording head  3 . 
     In the second embodiment described above, the nozzle plate  39 ′ is joined to the bottom surface of the communication substrate  41 ′ closer to the inside than the reservoir part  48 ; however, the invention is not limited thereto. In the fourth embodiment illustrated in  FIG. 15 , the nozzle plate  39 ′ is joined to the bottom surface of the reservoir part  48 . Specifically, the reservoir part  48  extends further inside than a position corresponding to the nozzle communication path  42 ′, and the nozzle plate  39 ′ is joined to the portion of the inside of the reservoir part  48 . Note that, together with the reservoir part  48 , the elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53  extend further inward than a position corresponding to the nozzle communication path  42 ′. The compliance sheet  18 ′ is provided on the outside of the nozzle plate in a region corresponding to the reservoir  45 . Note that, it is possible to adopt a configuration in which the compliance sheet  18 ′ extends further inward than a position corresponding to the nozzle communication path, in the same manner as the reservoir part  48 . A through hole  57  which communicates the nozzle communication path  42 ′ with the nozzle  40 ′ is formed in a position corresponding to the nozzle communication path  42 ′ of the reservoir part  48 , and openings (omitted from the drawings) are also formed in the same position in the elastic substrate  51 , the intermediary layer  52 , and the valve receiving body forming substrate  53 . Note that, since the other configuration is the same as that of the second embodiment described above, description thereof will be omitted. 
     In this manner, since the nozzle plate  39 ′ is formed below the reservoir part  48 , for example, when the bottom surface of the nozzle plate  39 ′ is wiped by a wiper (not shown), it is possible to suppress the occurrence of a problem in which the wiper is inhibited from abutting the nozzle plate  39 ′ by the reservoir part  48 . Accordingly, it is possible to more reliably wipe the bottom surface of the nozzle plate  39 ′ with the wiper. 
     In the embodiments described above, an ink jet recording head which is mounted to an ink jet printer is exemplified; however, as long as the piezoelectric element and the pressure chamber of the configurations described above are present, it is possible to apply the invention to an apparatus which ejects a liquid other than ink. For example, it is possible to apply the invention to a color material ejecting head which is used in the manufacture of a color filter of a liquid crystal display or the like, an electrode material ejecting head which is used in forming electrodes of an organic electro luminescence (EL) display, a face emission display (FED), and the like, a bio-organic matter ejecting head used in the manufacture of bio chips (biochemical elements), and the like.