Liquid jet head, and liquid jet device

Abstract

To provide a technique for lowering channel resistance from pressure chambers to nozzles.SOLUTION: A liquid jet head includes a nozzle plate formed with a first nozzle for jetting liquid, first and second pressure chambers arranged side by side in a first direction, third and fourth pressure chambers arranged side by side in the first direction, a first communication channel which is a channel extending along the nozzle plate, is connected to the first nozzle and communicates with the first to fourth pressure chambers, a first common liquid chamber communicating with the first and second pressure chambers, and a second common liquid chamber communicating with the third and fourth pressure chambers. The first and second pressure chambers, and the third and fourth pressure chambers are deviated in a second direction perpendicular to the first direction. When a width in the first direction of the first communication channel at a position overlapping the first nozzle when being viewed toward the nozzle plate in plan view is defined as a first width, and a width in the first direction of the first pressure chamber is defined as a pressure chamber width, the first width is equal to or more than the pressure chamber width.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This disclosure relates to a liquid injection head and a liquid injection device. [Background technology]

[0002] Patent Document 1 discloses a liquid injection head in which four pressure chambers are provided on both sides of the nozzle, and the flow paths from each of the four pressure chambers to the nozzle are merged near the nozzle. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-155768 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, the conventional technology described above had a problem in that the width of the flow path from the four pressure chambers to the nozzle was narrow, resulting in high flow resistance and poor injection efficiency. [Means for solving the problem]

[0005] A liquid injection head according to a first embodiment of the present disclosure comprises a nozzle plate on which a first nozzle for injecting liquid is formed; first and second pressure chambers arranged side by side in a first direction; third and fourth pressure chambers arranged side by side in the first direction; a first communication channel extending along the nozzle plate, connected to the first nozzle and communicating with the first to fourth pressure chambers; a first common liquid chamber communicating with the first and second pressure chambers; and a second common liquid chamber communicating with the third and fourth pressure chambers. The first and second pressure chambers and the third and fourth pressure chambers are offset in a second direction perpendicular to the first direction. When the width of the first communication channel in the first direction at a position overlapping with the first nozzle in a plan view toward the nozzle plate is defined as the first width, and the width of the first pressure chamber in the first direction is defined as the pressure chamber width, the first width is greater than or equal to the pressure chamber width.

[0006] A liquid injection head according to a second embodiment of the present disclosure comprises a nozzle plate on which a nozzle for injecting liquid is formed; when N is an integer of 3 or more, N pressure chambers A arranged in a line in a first direction; N pressure chambers B arranged in a line in the first direction, offset from the N pressure chambers A in a second direction perpendicular to the first direction; a communication channel extending along the nozzle plate, connected to the nozzle and communicating with the N pressure chambers A and the N pressure chambers B; a first common liquid chamber communicating with the N pressure chambers A; and a second common liquid chamber communicating with the N pressure chambers B. When the width of the communication channel in the first direction at a position overlapping with the nozzle in a plan view toward the nozzle plate is defined as the first width, and the width of the pressure chamber A in the first direction is defined as the pressure chamber width, the first width is greater than or equal to the pressure chamber width.

[0007] A liquid injection device according to a third embodiment of the present disclosure comprises a liquid injection head and a liquid storage unit for storing the liquid to be supplied to the liquid injection head. [Brief explanation of the drawing]

[0008] [Figure 1] An explanatory diagram showing the configuration of a liquid injection device in an embodiment. [Figure 2] Bottom view of the liquid injection head. [Figure 3] A cross-sectional view showing section III-III in Figure 2. [Figure 4] Figure 3 shows the flow paths for the three nozzles and a portion of the first and second common liquid chambers as viewed from the bottom. [Figure 5] Figure 3 shows a portion of the flow path for one nozzle, viewed from the bottom. [Figure 6] A magnified view of the flow path in Figure 5. [Figure 7] An explanatory diagram showing the relationship between pressure chamber width and wall thickness. [Figure 8] An explanatory diagram showing the relationship between pressure chamber width and wall thickness. [Figure 9] A diagram showing the shape of the flow path for each nozzle in the second embodiment. [Figure 10] A diagram showing the shape of the flow channels for each nozzle in the third embodiment. [Figure 11] A diagram showing the shape of the flow channels for each nozzle in the fourth embodiment. [Figure 12] A diagram showing the shape of the flow path for each nozzle in the fifth embodiment. [Figure 13] A diagram showing the shape of the flow path for each nozzle in the sixth embodiment. [Figure 14] A diagram showing the shape of the flow path for each nozzle in the seventh embodiment. [Figure 15] A diagram showing the shape of the flow path for each nozzle in the eighth embodiment. [Modes for carrying out the invention]

[0009] A. First Embodiment Figure 1 is an explanatory diagram showing the configuration of a liquid spray device 400 in an embodiment. The liquid spray device 400 is an inkjet type printing device that sprays ink, which is an example of a liquid, onto a medium PM. The composition of the ink is not particularly limited and may be, for example, an aqueous ink obtained by dissolving a colorant such as a dye or pigment in an aqueous solvent, a solvent-based ink obtained by dissolving a colorant in an organic solvent, or an ultraviolet-curable ink. The liquid spray device 400 may also spray paint as a liquid instead of ink. A liquid reservoir 420 for storing ink can be attached to the liquid spray device 400. The liquid spray device 400 performs printing by spraying the ink in the liquid reservoir 420 toward the medium PM. The liquid spray device 400 comprises a liquid spray head 100, a moving mechanism 430, a transport mechanism 440, a control unit 450, and a circulation mechanism 60.

[0010] The liquid spray head 100 is equipped with a plurality of nozzles 200 as shown in Figure 2, and sprays liquid ink supplied from the liquid reservoir 420 from the plurality of nozzles 200. Specific embodiments of the liquid reservoir 420 include, for example, a cartridge detachable from the liquid spray device 400, a bag-shaped ink pack made of a flexible film, and a container such as an ink tank that can be refilled with ink. The ink sprayed from the nozzles 200 lands on the medium PM. The medium PM is typically printing paper. However, the medium M is not limited to printing paper and may be any material to be printed on, such as a resin film or a cloth.

[0011] The moving mechanism 430 comprises a ring-shaped belt 432 and a carriage 434 fixed to the belt 432. The carriage 434 holds the liquid spray head 100. The moving mechanism 430 can move the liquid spray head 100 back and forth along the X direction by rotating the ring-shaped belt 432 in both directions.

[0012] The transport mechanism 440 transports the medium PM along the Y direction in between movements of the liquid spray head 100 by the moving mechanism 430. The Y direction is perpendicular to the X direction. In this embodiment, the X and Y directions are horizontal. The Z direction is intersecting the X and Y directions. In this embodiment, the Z direction is vertically downward. The liquid spray head 100 sprays ink along the Z direction while being transported along the X direction. The Z direction is also called the "spray direction Z". Furthermore, in the following description, the tip of the arrow indicating the X direction in the figure will be called the +X side and the base end will be called the -X side, the tip of the arrow indicating the Y direction in the figure will be called the +Y side and the base end will be called the -Y side, and the tip of the arrow indicating the Z direction in the figure will be called the +Z side and the base end will be called the -Z side.

[0013] The control unit 450 controls the ink ejection operation from the liquid ejection head 100. The control unit 450 controls the transport mechanism 440, the moving mechanism 430, and the liquid ejection head 100 to form an image on the medium PM.

[0014] Figure 2 is a bottom view of the liquid injection head 100. The liquid injection head 100 has a plurality of nozzles 200. The plurality of nozzles 200 are formed to penetrate a nozzle plate 240 arranged parallel to the XY plane. The plurality of nozzles 200 are arranged linearly along the Y direction to form a nozzle row NL. The nozzle plate 240 is manufactured, for example, by processing a silicon single crystal substrate using semiconductor processing technology. As the silicon single crystal substrate, for example, a silicon single crystal substrate with the (100) plane as the main surface is preferably used. The nozzle plate 240 may be made of a material such as stainless steel (SUS) or titanium.

[0015] Figure 3 is a cross-sectional view taken along the III-III section of Figure 2. Figure 4 shows the flow paths for three nozzles and parts of the first common liquid chamber 110 and the second common liquid chamber 120 as seen from the bottom of Figure 3. Figure 5 shows the flow path for one nozzle and parts of the common liquid chambers 110 and 120 as seen from the bottom of Figure 3. Figure 6 is an enlarged view of the flow path in Figure 5. Note that Figure 4 only shows the three individual nozzle flow paths 130, the first common liquid chamber 110, and the second common liquid chamber 120. For convenience of illustration, in Figure 5, the connecting flow path 350 is drawn with a solid line, the pressure chamber 330 with a dotted line, the drive element 300 with a dashed line, and the common liquid chambers 110 and 120 with a dashed line. In Figure 6, the connecting flow paths 321-324 and drive elements 301-304 are omitted from the illustration. Also, Figure 4 shows three nozzles 200, including nozzles 200a and 200b. When nozzle 200a, which is any one of the multiple nozzles 200, is designated as the "first nozzle," nozzle 200b is an example of the "second nozzle." The nozzle 200 shown in Figures 3, 5, and 5 is nozzle 200a.

[0016] In Figures 3 and subsequent figures, the first direction Dr1, the second direction Dr2, and the third direction Dr3 are also shown. The first direction Dr1 is the direction in which pressure chambers 331 and 332 are aligned, and the direction in which pressure chambers 333 and 334 are aligned. The second direction Dr2 is perpendicular to the first direction Dr1. Furthermore, the first direction Dr1 and the second direction Dr2 are parallel to the surface of the nozzle plate 240. The third direction Dr3 is the thickness direction of the nozzle plate 240. The thickness direction of the nozzle plate 240 means the direction along the shortest of the three sides of the nozzle plate 240. In this embodiment, the first direction Dr1 is parallel to the Y direction, the second direction Dr2 is parallel to the X direction, and the third direction Dr3 is parallel to the Z direction. However, the three directions Dr1 to Dr3 may be set to directions different from this example.

[0017] As shown in Figure 4, the spacing Pt1 between adjacent nozzles 200, that is, the distance between the centers of the nozzles 200 in the Y direction, is constant. Similarly, the spacing Pt2 between adjacent pressure chambers 330_L1 in the row L1, that is, the distance between the centers of the pressure chambers 330_L1 in the Y direction, is constant. The same relationship applies to row L2. Furthermore, the spacing Pt2 in row L1 is the same as the spacing Pt2 in row L2, and spacing Pt2 is half the spacing Pt1. Also, the spacing Pt2 of the pressure chambers 330 is the same as the spacing of the communication holes 340, and is the same as the spacing between the centers of the nozzles 200 in the Y direction.

[0018] As shown in Figure 3, the liquid spray head 100 has a first common liquid chamber 110 into which ink is supplied, a second common liquid chamber 120 into which ink is discharged, and a nozzle-specific flow path 130 connecting the first common liquid chamber 110 and the second common liquid chamber 120. The first common liquid chamber 110 and the second common liquid chamber 120 are provided in common for a plurality of nozzles 200, and the nozzle-specific flow path 130 is provided individually for each nozzle 200. Each of the common liquid chambers 110 and 120 extends in the Y direction, which is the direction along the nozzle row NL. That is, the longitudinal direction of the common liquid chambers 110 and 120 is parallel to the direction in which the plurality of nozzles 200 are lined up.

[0019] The liquid injection head 100 has a row L1 of multiple pressure chambers 330 communicating with a first common liquid chamber 110, and a row L2 of multiple pressure chambers 330 communicating with a second common liquid chamber 120. Row L1 is composed of multiple pressure chambers 330 arranged in the Y direction, and row L2 is composed of multiple pressure chambers 330 arranged in the Y direction. Row L1 is located on the -X side with respect to the nozzle row NL, and row L2 is located on the +X side with respect to the nozzle row NL. Hereafter, the multiple pressure chambers 330 constituting row L1 will be referred to as pressure chamber 330_L1, and the multiple pressure chambers 330 constituting row L2 will be referred to as pressure chamber 330_L2. For details regarding the drive element 300, connecting channel 320, and communication hole 340, which will be described later, the drive element 300 corresponding to row L1 will be referred to as drive element 300_L1, the drive element 300 corresponding to row L2 will be referred to as drive element 300_L2, the connecting channel 320 corresponding to row L1 will be referred to as connecting channel 320_L1, the connecting channel 320 corresponding to row L2 will be referred to as connecting channel 320_L2, the communication hole 340 corresponding to row L1 will be referred to as communication hole 340_L1, and the communication hole 340 corresponding to row L2 will be referred to as communication hole 340_L2.

[0020] In this embodiment, the nozzle-specific flow path 130 corresponding to one nozzle 200 includes two pressure chambers 330_L1 in row L1, two pressure chambers 330_L2 in row L2, two connecting flow paths 320_L1 corresponding to each of the two pressure chambers 330_L1, two connecting flow paths 320_L2 corresponding to each of the two pressure chambers 330_L2, two communication holes 340_L1 corresponding to each of the two pressure chambers 330_L1, two communication holes 340_L2 corresponding to each of the two pressure chambers 330_L2, and a communication flow path 350. Here, the two pressure chambers 330_L1 in row L1 are referred to as pressure chambers 331 and 332, the two pressure chambers 330_L2 in row L2 are referred to as pressure chambers 333 and 334, the two connecting passages 320_L1 are referred to as connecting passages 321 and 322, the two connecting passages 320_L2 are referred to as connecting passages 323 and 324, the two communication holes 340_L1 are referred to as communication holes 341 and 342, and the two communication holes 340_L2 are referred to as communication holes 343 and 344. In addition, the four drive elements 300 corresponding to each of the pressure chambers 331 to 334 are referred to as drive elements 301 to 304.

[0021] Each of the common liquid chambers 110 and 120 can be considered to extend in the Y direction or in the direction in which adjacent pressure chambers 331 and 332 are aligned, in other words, in the direction in which the row L1 of pressure chambers 330 extends. In this embodiment, the direction in which adjacent pressure chambers 331 and 332 are aligned is an example of the "first direction". In addition, the multiple nozzle-specific flow paths 130 are aligned in the Y direction along the nozzle row NL.

[0022] The lower parts of the common liquid chambers 110 and 120 and the multiple nozzle-specific flow paths 130 are mainly formed by a connecting plate 140. The connecting plate 140 may be constructed by stacking multiple plate-shaped members. The housing portion 160 and the pressure chamber substrate 250 are installed on the upper surface of the connecting plate 140, i.e., the surface of the connecting plate 140 facing the -Z side. The pressure chamber substrate 250 is located inside the housing portion 160 in a plan view in the Z direction. The diaphragm 310 is located on the upper surface of the pressure chamber substrate 250, i.e., the surface of the pressure chamber substrate 250 facing the -Z side. Multiple pressure chambers 330 are provided in the pressure chamber substrate 250. Each pressure chamber 330 is a space defined by the connecting plate 140, the diaphragm 310, and the pressure chamber substrate 250. The pressure chamber substrate 250 is manufactured, for example, by processing a silicon single crystal substrate using semiconductor processing technology. As the silicon single crystal substrate, for example, a (110) substrate, that is, a silicon single crystal substrate whose main surface is the (110) plane, is preferably used.

[0023] The diaphragm 310 is an elastically vibrating plate-shaped member. The diaphragm 310 is a laminate including, for example, a first layer made of silicon oxide (SiO2) and a second layer made of zirconium oxide (ZrO2). Here, other layers such as metal oxides may be interposed between the first and second layers. Part or all of the diaphragm 54 may be integrally formed from the same material as the pressure chamber substrate 250. For example, the diaphragm 310 and the pressure chamber substrate 250 can be integrally formed by selectively removing a portion in the thickness direction of a plate-shaped member of a predetermined thickness corresponding to the pressure chamber 330 by etching or the like. Alternatively, the diaphragm 310 may be composed of layers of a single material.

[0024] A nozzle plate 240 is installed on the lower surface of the communication plate 140, that is, the surface of the communication plate 140 facing the +Z side. The lower ends of the first common liquid chamber 110 and the second common liquid chamber 120, that is, the +Z side ends of the first common liquid chamber 110 and the second common liquid chamber 120, are sealed with a flexible sealing film 150 made of a resin film or a thin film of metal.

[0025] A wiring board 59 is bonded to the -Z-facing side of the diaphragm 310. The wiring board 59 is a mounting component on which multiple wires are formed for electrically connecting the control unit 450 and the liquid injection head 100. The wiring board 59 is a flexible wiring board such as an FPC (Flexible Printed Circuit) or FFC (Flexible Flat Cable). A drive circuit 70 for driving the drive elements 300 is mounted on the wiring board 59. The drive circuit 70 supplies drive signals to each drive element 300.

[0026] Multiple drive elements 300 are provided on the upper surface of the diaphragm 310, that is, the surface facing the -Z side of the diaphragm 310, corresponding to each pressure chamber 330. These drive elements 300 are composed of, for example, piezoelectric elements. A piezoelectric element is composed of, for example, a piezoelectric layer and two electrodes provided so as to sandwich the piezoelectric layer. For example, when the drive elements 301 to 304, which are piezoelectric elements, vibrate, these vibrations are transmitted to the pressure chambers 331 to 334, respectively, and pressure waves are generated in the pressure chambers 331 to 334. The ink is ejected from the nozzle 200 by the pressure generated by the drive elements 301 to 304. Alternatively, instead of piezoelectric elements, heating elements that heat the ink in the pressure chamber 330 may be used as drive elements.

[0027] A circulation mechanism 60 is connected to the common liquid chambers 110 and 120. The circulation mechanism 60 supplies ink to the first common liquid chamber 110 and recovers the ink discharged from the second common liquid chamber 120 for resupply to the first common liquid chamber 110. The circulation mechanism 60 includes a first supply pump 61, a second supply pump 62, a storage container 63, a recovery channel 64, and a supply channel 65.

[0028] The first supply pump 61 is a pump that supplies ink stored in the liquid storage section 420 to the storage container 63. The storage container 63 is a sub-tank that temporarily stores the ink supplied from the liquid storage section 420. The recovery channel 64 is interposed between the second common liquid chamber 120 and the storage container 63 and is a channel for recovering ink from the second common liquid chamber 120 into the storage container 63. The ink stored in the liquid storage section 420 is supplied to the storage container 63 from the first supply pump 61. Furthermore, ink that was supplied from the first common liquid chamber 110 to each nozzle-specific channel 130 but was not ejected from the nozzles 200 and was discharged from each nozzle-specific channel 130 to the second common liquid chamber 120 is supplied to the storage container 63 via the recovery channel 64. The second supply pump 62 is a pump that delivers the ink stored in the storage container 63. The supply channel 65 is interposed between the first common liquid chamber 110 and the storage container 63, and is a channel for supplying ink from the storage container 63 to the first common liquid chamber 110.

[0029] The opening 161 at the upper end of the first common liquid chamber 110, i.e., the -Z end of the first common liquid chamber 110, is connected to the supply channel 65, which is outside the liquid injection head 100. In other words, the opening 161 in this embodiment functions as an inlet for introducing liquid from the circulation mechanism 60. The opening 162 at the upper end of the second common liquid chamber 120, i.e., the -Z end of the second common liquid chamber 120, is connected to the recovery channel 64 of the circulation mechanism 60, which is outside the liquid injection head 100. In other words, the opening 162 in this embodiment functions as an outlet for discharging liquid from the circulation mechanism 60.

[0030] The nozzle-specific flow path 130 has the following flow paths and spaces. In the following description, the term "connection" is used to mean a direct connection. The term "communication" is used in a broader sense to include not only direct connections but also indirect connections. <Connection channels 321-324> The connecting channel 321 connects the first common liquid chamber 110 and the pressure chamber 331. The connecting channel 322 connects the first common liquid chamber 110 and the pressure chamber 332. The connecting channel 323 connects the second common liquid chamber 120 and the pressure chamber 333. The connecting channel 324 connects the second common liquid chamber 120 and the pressure chamber 334. The connecting channels 321 to 324 are all channels that extend in the Z direction and penetrate the connecting plate 140. In Figures 5 and 6, hatching is applied to the connecting channels 321 to 324 for illustrative purposes. The portion where the connecting channel 320 intersects with the pressure chamber 330 can be considered as part of the pressure chamber 330.

[0031] <Pressure chambers 331-334> Pressure chambers 331 to 334 are spaces that receive pressure changes from drive elements 301 to 304, respectively. Pressure chambers 331 and 332 are arranged side by side in the first direction Dr1, and pressure chambers 333 and 334 are also arranged side by side in the first direction Dr1. In this embodiment, the first direction Dr1 is parallel to the Y direction. Pressure chambers 331 and 332 and pressure chambers 333 and 334 are offset in the second direction Dr2, which is perpendicular to the first direction Dr1. In this embodiment, the second direction Dr2 is parallel to the X direction. The pressure waves generated in pressure chambers 331 to 334 reach the nozzle 200 and eject ink from the nozzle 200. It is preferable that pressure chambers 331 to 334 have the same shape. In this embodiment, multiple pressure chambers 331 to 334 are arranged in a staggered pattern. Each pressure chamber 330 extends in the second direction Dr2. Here, the pressure chamber 331a communicating with the nozzle 200a is an example of a "first pressure chamber," the pressure chamber 332a communicating with the nozzle 200a is an example of a "second pressure chamber," the pressure chamber 333a communicating with the nozzle 200a is an example of a "third pressure chamber," and the pressure chamber 334a communicating with the nozzle 200a is an example of a "fourth pressure chamber."

[0032] <Communication holes 341~344> Communication holes 341 to 344 each extend in the Z direction and are passages that connect the communication passage 350 to the pressure chambers 331 to 334, respectively. In other words, each pressure chamber 330 is connected to the connecting passage 320 at one end and to the communication hole 340 at the other end. In Figures 5 and 6, hatching is applied to communication holes 341 to 344 for illustrative purposes. Also, in Figure 6, the connecting passages 321 to 324 and the drive elements 301 to 304 are not shown. Communication holes 341 and 342 are arranged side by side in the first direction Dr1, and communication holes 343 and 344 are also arranged side by side in the first direction Dr1. Communication holes 341 to 344 are passages that extend in the same direction as the connecting passages 321 to 324 and penetrate the communication plate 140. It is preferable that the communication holes 341 to 344 have the same shape. The portion where the communication hole 340 and the pressure chamber 330 intersect can be considered as part of the pressure chamber 330.

[0033] <Communication channel 350> As shown in Figure 3, the communication channel 350 is connected to the nozzle 200 and is a channel that connects the nozzle 200 to pressure chambers 331 to 334. The communication channel 350 is a channel that extends along the nozzle surface of the nozzle plate 240 on which the multiple nozzles 200 are formed, and a nozzle 200 is provided in the middle of the communication channel 350. Specifically, the communication channel 350 extends along the X direction and is defined by the communication plate 140 and the -Z-facing surface of the nozzle plate 240. In other words, the communication channel 350 is a channel whose longitudinal direction is the second direction Dr2. The portion where the communication holes 341 to 344 intersect with the communication channel 350 can be considered as part of the communication channel 350. Here, the communication channel 350a connected to the nozzle 200a is an example of the "first communication channel".

[0034] As the ink, for example, a pseudoplastic liquid can be used. More specifically, the ink has a shear rate of 1000 s at 25°C. -1 The viscosity is between 0.01 Pa·s and 0.2 Pa·s, and the shear rate is 0.01 s -1It is preferable that the viscosity at this time is 0.5 Pa·s or more and 50 Pa·s or less. In this embodiment, by using four pressure chambers 331 to 334, the cross-sectional area of ​​each flow path is reduced, the flow velocity is increased, and the viscosity of the ink is reduced, making it possible to use a pseudoplastic liquid ink. However, from the pressure chambers 331 to 334 to the nozzle 200, it is undesirable to make the flow resistance excessively large in order to efficiently utilize the energy of the drive elements 301 to 304. Therefore, in this embodiment, the width W of the connecting flow path 350 shown in Figure 6 R1 By increasing this value, the flow resistance is reduced.

[0035] In this embodiment, four pressure chambers 331 to 334 were provided for one nozzle 200, but five or more pressure chambers may be provided. In any case, the drive elements are provided to correspond to each pressure chamber.

[0036] The nozzle-specific flow paths 130 in this embodiment can be considered to include four individual flow paths corresponding to the four drive elements 301 to 304, and a flow path common to the four drive elements 301 to 304. An "individual flow path" is a flow path that includes at least a pressure chamber 330, and one individual flow path corresponds to one drive element 300. In this embodiment, the first individual flow path can be considered to include a connecting flow path 321, a pressure chamber 331, and a communication hole 341. The second to fourth individual flow paths can be understood in a similar manner. Furthermore, the flow path common to the four drive elements 301 to 304, in other words, the flow path common to the pressure chambers 331 to 334, corresponds to the communication flow path 350 connected to the aforementioned four individual flow paths. In addition, the multiple nozzle-specific flow paths 130 in this embodiment have substantially the same structure.

[0037] The liquid injection head 100 of the first embodiment has the following various features, mainly related to flow resistance. <Feature D1> As shown in Figure 6, in a plan view toward the nozzle plate 240, the width of the first direction Dr1 of the communication channel 350 at the position overlapping with the nozzle 200 is the first width W. R1and set the width of the pressure chamber 331 in the first direction Dr1 to the pressure chamber width W C1 When it is set as W C1 ≦W R1 is satisfied. According to this feature D1, since the first width W of the communication flow path 350 R1 is wide, a decrease in injection efficiency can be suppressed.

[0038] In addition, the first width W of the communication flow path 350 R1 is preferably larger than the pressure chamber width W C1 , and more preferably 1.5 times or more of the pressure chamber width W C1 . Also, the first width W of the communication flow path 350 R1 is preferably 2 times or less of the pressure chamber width W C1 , and particularly preferably equal to 2 times of the pressure chamber width W C1 .

[0039] In this embodiment, the width W of the pressure chamber 331 C1 is constant regardless of the position along the second direction Dr2. However, when the width W of the pressure chamber 331 C1 varies along the second direction Dr2, it is preferable to set the "pressure chamber width W C1 " in the above feature D1 to its maximum value. The four pressure chambers 331 to 334 preferably have equal widths W C1 ~W C4 in the first direction Dr1, and preferably have equal lengths L C1 in the second direction Dr2.

[0040] In the present disclosure, the first width W of the communication flow path 350 R1 means the distance between two wall surfaces directly facing each other in the first direction Dr1 among the wall surfaces defining the communication flow path 350. "Two wall surfaces directly facing each other" means that no other wall surfaces or structures are included between them. The widths and lengths of other flow paths such as the pressure chamber 331 are the same.

[0041] <Feature D2> As shown in FIG. 3, the height in the third direction Dr3 of the communication flow path 350 at the position overlapping the nozzle 200 in plan view is the first height H R1In this case, the first width W of the connecting channel 350 shown in Figure 6 R1 is the first height H R1 That's all. Here, the first height H of the communication channel 350 at the position overlapping with the nozzle 200. R1 " refers to the height of the communication channel 350 assuming there is no recess in the nozzle 200. In other words, the first height H of the communication channel 350. R1 This is the distance between the upper surface of the nozzle plate 240 and the lower surface of the communication plate 140. That is, the first height H R1 This is the distance Dr3 in the third direction between the surface of the nozzle plate 240 that defines the communication channel 350 and the surface of the communication plate 140 that faces the nozzle plate 240. This feature D2 allows for the reduction of the flow resistance of the communication channel 350 while ensuring the rigidity of the communication plate 140. Note that the first width W R1 is the first height H R1 It is preferable to do so.

[0042] <Feature D3> As shown in Figure 3, the thickness of the communication plate 140 in the third direction Dr3 at the position overlapping with the nozzle 200 in a plan view is the first thickness T. R1 In this case, the first thickness T R1 The first height H of the connecting channel 350 R1 Larger. According to this feature D3, the rigidity of the connecting plate 140 can be ensured while reducing the flow resistance of the 350 connecting channel. R1 Preferably, the first height H R1 It is more than twice, more preferably three times or more, and even more preferably four times or more.

[0043] <Feature D4> Width W in the first direction Dr1 of the partition wall PW1 separating pressure chamber 331 and pressure chamber 332 S1 Twice that is V1 (=2 × W) S1 ) and the width of the partition wall PW2 that separates two adjacent communication channels 350 in the first direction Dr1 is set to W S2 In this case, V1 ≤ W S2 ≤V1+W C1 It satisfies the condition. Width W in the first direction Dr1 of the partition wall PW1 separating pressure chamber 331 and pressure chamber 332 S1 This is shown in Figure 6. Also, the width W of the partition wall PW2 that separates the two adjacent communication channels 350 in the first direction Dr1 is shown. S2 This is shown in Figures 6 and 3. Here, V1 is the "first value", and V1 + W C1 This is the "second value". Note that the width W of the first direction Dr1 is the width of the partition wall PW2 that separates the two adjacent communication channels 350 in the first direction Dr1. S2 "The width W of the partition wall PW2 is measured at the position where the nozzle 200 is located with respect to the second direction Dr2." S2 That is the case.

[0044] Figures 7 and 8 are explanatory diagrams showing the relationship between pressure chamber width and wall thickness in relation to the above-mentioned features D4 and D1. Figures 7 and 8 schematically depict two adjacent nozzles 200a and 200b in the Y direction, a first communication channel 350a and pressure chambers 331a to 334a related to nozzle 200a, a second communication channel 350b and pressure chambers 331b to 334b ​​related to nozzle 200b, and partition walls Pw1 and Pw2. Here, pressure chamber 331b communicating with nozzle 200b is an example of a "fifth pressure chamber," pressure chamber 332b communicating with nozzle 200b is an example of a "sixth pressure chamber," pressure chamber 333b communicating with nozzle 200b is an example of a "seventh pressure chamber," and pressure chamber 334b ​​communicating with nozzle 200b is an example of an "eighth pressure chamber." Furthermore, the width W of the partition wall Pw1 that separates the two adjacent pressure chambers 330 in the first direction Dr1 is also specified. S1 The pressure chamber width W of each pressure chamber 330 is constant, and the pressure chamber width W of each pressure chamber 330 is constant. C1 It is also constant. In both Figure 7 and Figure 8, (2 × W C1 +2×W S1 )=(W R1 +W S2 The flow channels are arranged such that the following condition is met.

[0045] The example in Figure 7 shows that in the above feature D1, W R1 = 2 × W C1 This corresponds to the case where, in the above feature D4, W S2 =V1=(2×WS1 ) is true. On the other hand, in the example of Figure 8, W in the above feature D1 R1 =W C1 This corresponds to the case where, in the above feature D4, W S2 =(V1+W C1 ) = (2 × W S1 +W C1 The above-mentioned characteristic D4 is established. Thus, when the set of nozzle 200, pressure chamber 330, and communication channel 350 is densely arranged at regular intervals along the first direction Dr1, it is preferable to have the above-mentioned characteristic D4.

[0046] As mentioned above, the communication channel 350 has its longitudinal direction in the second direction Dr2. That is, the distance L in the second direction Dr2 between the two pressure chamber rows 330_L1 and 330_L2 shown in Figures 4 and 6. G This refers to the first width W of the first direction Dr1 of the communication channel 350. R1 It is set to be larger than that.

[0047] As described above, according to the first embodiment, the liquid injection head 100 has at least some of the above-mentioned features D1 to D4, and the first width W of the communication channel 350 R1 Because the range is set broadly, the decrease in injection efficiency can be suppressed. However, some of the features mentioned above can be omitted.

[0048] Furthermore, in order to reduce the resistance of the communication channel 350, its width W R1 Instead of increasing the height H R1 It is also possible to consider ways to increase the height H of the connecting channel 350. R1 Increasing the height H of the communication channel 350 may result in an undesirable structure because it increases the etching depth of the communication plate 140, leading to a decrease in rigidity. On the other hand, in the first embodiment described above, the height H of the communication channel 350 R1 Since there is no need to increase the size, there is the advantage that the rigidity of the connecting plate 140 will not be excessively reduced.

[0049] B. Other Embodiments Figure 9 shows the shape of the nozzle-specific flow path 130 in the second embodiment. The main difference from the first embodiment shown in Figure 6 is only the shape of the communication flow path 350; the other configurations are almost the same as in the first embodiment. In the second embodiment, the communication flow path 350 includes a first part 351, a second part 352, and a third part 353. The first part 351 of the communication flow path 350 is located at one end of the communication flow path 350 and is connected to communication holes 341 and 342. The second part 352 of the communication flow path 350 is located at the other end of the communication flow path 350 and is connected to communication holes 343 and 344. The third part 353 of the communication flow path 350 is connected between the first part 351 and the second part 352. The third part 353 is connected to the first part 351 and the second part 352 by inclined surfaces SP1 to SP4. First width W of the first direction Dr1 of the third part 353 R1 The width W of the first part 351 and the second part 352 is R2 It is smaller than that.

[0050] The second embodiment has the following features in addition to the features of the first embodiment described above. <Feature D5> In a plan view, the communication channel 350 has a first width W at a position between the pressure chambers 331 and 332 and the nozzle 200, where the width of the communication channel 350 in the first direction Dr1 coincides with the nozzle 200 in a plan view. R1 Larger than the second width W R2 This includes the portion that is W. R2 The portion having the is part of the first portion 351 and extends for a predetermined length in the second direction Dr2.

[0051] Similarly, in a plan view, the width of the communication channel 350 in the first direction Dr1 is such that it overlaps with the nozzle 200 at a position between the pressure chambers 333 and 334 and the nozzle 200. R1 Larger than the second width W R2 This includes the portion that is W. R2 The portion having is part of the second portion 352 and extends for a predetermined length in the second direction Dr2. The second width W in the first direction Dr1 of the first portion 351.R2 and the second width W of the first direction Dr1 of the second part 352 R2 are preferably equal to each other.

[0052] According to this feature D5, the flow rate can be increased in the vicinity of the nozzle 200. When a pseudoplastic liquid is used, the viscosity of the liquid can be reduced by increasing the flow rate, so the advantages of feature D5 are particularly prominent.

[0053] In addition, under feature D5, it is preferable to satisfy the following formula (1), and more preferably to satisfy the following formula (2). 0.1×W C1 ≦(W R2 -W R1 ) …(1) 0.2×W C1 ≦(W R2 -W R1 ) …(2) That is, the value (W R2 minus the first width W R1 from the second width W R2 -W R1 ) is preferably 0.1 times or more of the pressure chamber width W C1 , and more preferably 0.2 times or more.

[0054] In addition, it is preferable to satisfy both of the following formulas (3a) and (3b). W R1 <(W C1 ×1.5) …(3a) (W C1 ×1.5)<W R2 ≦(W C1 ×2) …(3b)

[0055] The first width W R1 is more preferably 1.5 times or less of the pressure chamber width W C1 , more preferably 1.4 times or less, more preferably 1.3 times or less, more preferably 1.2 times or less, and more preferably 1.1 times or less. Also, the first width W R1 is particularly preferably equal to the pressure chamber width W C1 . Also, the second width WR2 The pressure chamber width W C1 It is more preferable to make it 1.5 times or more, more preferable to make it 1.6 times or more, more preferable to make it 1.7 times or more, more preferable to make it 1.8 times or more, and more preferable to make it 1.9 times or more. Also, the second width W R2 The pressure chamber width W C1 It is particularly preferable that it be equal to twice that amount.

[0056] The second embodiment is preferably further characterized by the following features. <Feature D6> Of the connecting channel 350, the first width W R1 The first length L of the second direction Dr2 of the portion having R1 The total length L of the second direction Dr2 of the communication channel 350 R Its length is between 4% and 30% of the total length. According to this feature D6, it is possible to reduce the viscosity of the pseudoplastic liquid near the nozzle 200 while suppressing the decrease in injection efficiency by reducing the flow resistance up to just before the nozzle.

[0057] Figure 10 shows the shape of the nozzle-specific flow path 130 in the third embodiment. The main difference from the first embodiment shown in Figure 6 is only the shape of the communication flow path 350; the other configurations are almost the same as in the first embodiment. In addition, in the third embodiment, the width W of the first direction Dr1 of the third portion 353 R1 However, the width W of a part of the first section 351 R3 and width W of part of the second part 352 R3 It differs from the second embodiment in that it is larger than the first embodiment.

[0058] The third embodiment has the following features in addition to the features of the first embodiment described above. <Feature D7> In a plan view, the communication channel 350 has a first width W at a position between the first pressure chamber 331 and the second pressure chamber 332 and the nozzle 200, where the width of the communication channel 350 in the first direction Dr1 coincides with the nozzle 200 in a plan view. R1 The third width W is smaller than R3 This includes the portion that is W.R3 The portion having the is part of the first portion 351 and extends for a predetermined length in the second direction Dr2.

[0059] Similarly, in a plan view, the width of the communication channel 350 in the first direction Dr1 is such that it overlaps with the nozzle 200 at a position between the pressure chambers 333 and 334 and the nozzle 200. R1 The third width W is smaller than R3 This includes the portion that is W. R3 The portion having is part of the second portion 352 and extends for a predetermined length in the second direction Dr2. The third width W in the first direction Dr1 of the first portion 351. R3 and the third width W of the first direction Dr1 of the second part 352 R3 It is preferable that they are equal to each other.

[0060] Generally, it is known that the faster the ink flow rate, the more likely variations are to occur in the concentration of particles contained in the ink. Therefore, if the ink flow rate directly above nozzle 200 is high, the concentration of particles contained in the ink directly above the nozzle will decrease. According to feature D7, widening the flow path directly above nozzle 200 reduces the flow rate directly above nozzle 200, which has the effect of making it easier to equalize the concentration of particles contained in the ink near nozzle 200.

[0061] Furthermore, under feature D7, it is preferable that equation (4) below is satisfied, and even more preferable that equation (5) is satisfied. 0.1 × W C1 ≤(W R1 -W R3 ) …(4) 0.2 × W C1 ≤(W R1 -W R3 ) …(5) That is, the third width W R3 From the first width W R1 The value obtained by subtracting (W R3 -W R1 ) but pressure chamber width W C1 It is preferable that it be 0.1 times or more, and more preferably 0.2 times or more.

[0062] Furthermore, it is preferable that both equations (6a) and (6b) below are satisfied. (W C1 ×1.5) <W R1 …(6a) W C1 ≤W R3 <(W C1 ×1.5) …(6b)

[0063] 1st width W R1 The pressure chamber width W C1 It is more preferable to make it 1.5 times or more, more preferable to make it 1.6 times or more, more preferable to make it 1.7 times or more, more preferable to make it 1.8 times or more, and more preferable to make it 1.9 times or more. Also, the first width W R1 The pressure chamber width W C1 It is particularly preferable that it be equal to twice the amount. Also, the third width W R3 The pressure chamber width W C1 It is more preferable to make it 1.5 times or less, more preferable to make it 1.4 times or less, more preferable to make it 1.3 times or less, more preferable to make it 1.2 times or less, and more preferable to make it 1.1 times or less. Also, the third width W R3 The pressure chamber width W C1 It is especially preferable that it be equal to [this value].

[0064] The third embodiment is preferably further characterized by the following features. <Feature D8> Of the connecting channel 350, the first width W R1 The first length L of the second direction Dr2 of the portion having R1 The total length L of the second direction Dr2 of the communication channel 350 R Its length is between 4% and 30% of the total length. This feature D8 allows for more uniform distribution of particle density within the ink.

[0065] Considering the first to third embodiments described above, the communication channel 350 preferably has the following characteristics. <Feature D9> In a plan view, the average width of the first direction Dr1 of the communication channel 350 from pressure chambers 331, 332 to pressure chambers 333, 334 is the pressure chamber width W. C1 That concludes the explanation. Note that "the communication channel 350 from pressure chambers 331, 332 to pressure chambers 333, 334 in a plan view" refers to the portion of the communication channel 350 between pressure chambers 331, 332 and pressure chambers 333, 334 in a plan view, and does not include the portion of the communication channel 350 that overlaps with pressure chambers 331, 332 or pressure chambers 333, 334 in a plan view. According to this feature D9, the flow resistance of the communication channel 350 can be sufficiently reduced.

[0066] Figures 11 to 13 show the shapes of the nozzle-specific flow paths 130 in the fourth to sixth embodiments. The main difference between these fourth to sixth embodiments and the first embodiment shown in Figure 6 is only the shape of the communication flow path 350; the other configurations are almost the same as those of the first embodiment. In the fourth embodiment shown in Figure 11, the entire communication flow path 350 is linear, similar to the first embodiment, but extends in a direction inclined from the second direction Dr2. In the fifth embodiment shown in Figure 12 and the sixth embodiment shown in Figure 13, the communication flow path 350 is bent midway. However, in the fourth to sixth embodiments as well, the fact that the entire communication flow path 350 extends in the second direction Dr2 is the same as in the first embodiment. It is preferable that the fourth to sixth embodiments also have the features D1 to D4 described in the first embodiment. Furthermore, the features D5 to D9 described above may be applied to the fourth to sixth embodiments.

[0067] Figure 14 shows the shape of the nozzle-specific flow path 130 in the seventh embodiment. The main difference between the seventh embodiment and the first embodiment shown in Figure 6 is the length L of the communication flow path 350 along the second direction Dr2. R Only this is the case; the other configurations are substantially the same as in the first embodiment. That is, in the seventh embodiment, the length L of the communication channel 350 is R However, it is abbreviated from the first embodiment.

[0068] In Figure 14, the length L of the second direction Dr2 of the portion of the communication channel 350 between pressure chamber row 330_L1 and pressure chamber row 330_L2 is further shown.G This is shown. This length L G The first width W of the connecting channel 350 R1 The following is preferable. Also, this length L G The length L of the second direction Dr2 of the pressure chamber 330 is C1 The following is preferable. Furthermore, the total length L of the second direction Dr2 of the communication channel 350 R The length L of the second direction Dr2 of the pressure chamber 330 is C1 The following is preferable. Note that the first width W of the communication channel 350 R1 The width W of the pressure chamber 330 in the first direction Dr1 is C1 It may be smaller than that. That is, the seventh embodiment does not have to have the feature D1 described in the first embodiment. However, it is also possible to apply one or more of the above-mentioned features D1 to D9 to the seventh embodiment. In the seventh embodiment, the length L of the communication channel 350 R Because it is short, the flow resistance can be further reduced.

[0069] Figure 15 shows the nozzle-specific flow paths 130 in the eighth embodiment. In the eighth embodiment, when N is an integer of 3 or more, there are N pressure chambers 330A and N pressure chambers 330B arranged in a line in the first direction Dr1. The N pressure chambers 330B are offset from the N pressure chambers 330A in the second direction Dr2. In the example in Figure 15, N is 3, but N may be 4 or more. The N communication holes 340A connect the communication flow path 350 to the N pressure chambers 330A, respectively, and the N communication holes 340B connect the communication flow path 350 to the N pressure chambers 330B, respectively. Here, pressure chamber 330A is an example of "pressure chamber A", and pressure chamber 330B is an example of "pressure chamber B".

[0070] The eighth embodiment has the following features. <Feature D10> In a plan view toward the nozzle plate 240, the width of the first direction Dr1 of the communication channel 350 at the position overlapping with the nozzle 200 is defined as the first width W. R1 The width of the pressure chamber 330A in the first direction Dr1 is defined as the pressure chamber width W. C1 When that happens, W C1 ≤WR1 It satisfies the condition. This feature D10 corresponds to feature D1 of the first embodiment described above.

[0071] The eighth embodiment is preferably further characterized by the following features. <Feature D11> (N-1) × W C1 ≤W R1 ≤N×W C1 It satisfies the condition. That is, the first width W R1 The pressure chamber width W C1 It is preferable that it is (N-1) times or more and N times or less.

[0072] The eighth embodiment, like the first embodiment described above, has a communication channel 350 with a width W R1 Because the area is wide, a decrease in injection efficiency can be suppressed. Furthermore, some or all of the above-described features D2 to D9 may be adopted in the eighth embodiment.

[0073] • Variation 1 In the embodiments described above, a serial-type liquid injection device 400 is exemplified, in which a carriage 434 holding the liquid injection heads 100 is reciprocated. However, this disclosure can also be applied to a line-type liquid injection device in which a plurality of nozzles 200 are distributed across the entire width of the medium PM. That is, the carriage holding the liquid injection heads 100 is not limited to a serial-type carriage, but may be a structure that supports the liquid injection heads 100 in a line-type configuration. In this case, for example, a plurality of liquid injection heads 100 are arranged in a line in the width direction of the medium PM, and the plurality of liquid injection heads 100 are held together in a single carriage.

[0074] • Variation 2 In the embodiments described above, a liquid injection device 400 equipped with a circulation mechanism 60 is exemplified, but the liquid injection device 400 does not necessarily have to be equipped with a circulation mechanism 60. That is, both openings 161 and 162 of the housing portion 160 are inlets for introducing liquid from the liquid storage portion 420, and both the first common liquid chamber 110 and the second common liquid chamber 120 may be used as flow paths for supplying the liquid supplied from the liquid storage portion 420 to the nozzle 200.

[0075] • Modification example 3 In each of the above-described configurations, one connecting channel 320 was connected to each of the pressure chambers 331 to 334. However, a common connecting channel 320 may be provided for pressure chambers 331 and 332 connected to the same first common liquid chamber 110. In other words, a configuration in which one connecting channel 320 is provided for multiple pressure chambers 330 is also possible. The same applies to pressure chambers 333 and 334 connected to the same second common liquid chamber 120. In Modification 3, when considering four individual channels corresponding to the individual pressure chambers 331 to 334, for example, the first individual channel would not include the connecting channel 320. The second to fourth individual channels can be understood in the same way.

[0076] • Modification 4 In each of the above embodiments, the connecting channel 320 is a channel that extends in the Z direction, but the connecting channel 320 may also be a channel that extends in a direction intersecting the Z direction, or a channel that includes both a portion that extends in the Z direction and a portion that extends in a direction intersecting the Z direction.

[0077] • Variation 5 The liquid spraying devices exemplified in the above-described form can be used in various devices such as facsimile machines and photocopiers, in addition to equipment dedicated to printing. However, the applications of liquid spraying devices are not limited to printing. For example, liquid spraying devices that spray colorant solutions are used as manufacturing equipment for forming color filters in display devices such as liquid crystal display panels. Liquid spraying devices that spray conductive material solutions are used as manufacturing equipment for forming wiring and electrodes on wiring boards. Furthermore, liquid spraying devices that spray solutions of organic substances related to living organisms are used, for example, as manufacturing equipment for producing biochips.

[0078] Other forms: This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit. For example, this disclosure can also be implemented in the following forms (aspects). The technical features in the embodiments described above that correspond to the technical features in each of the forms described below can be replaced or combined as appropriate in order to solve some or all of the problems of this disclosure, or to achieve some or all of the effects of this disclosure. Furthermore, if such technical features are not described as essential in this specification, they can be deleted as appropriate.

[0079] (1) A liquid spray head according to a first embodiment of the present disclosure comprises a nozzle plate on which a first nozzle for spraying liquid is formed, first and second pressure chambers arranged side by side in a first direction, third and fourth pressure chambers arranged side by side in the first direction, a communication channel extending along the nozzle plate, connected to the first nozzle and communicating with the first to fourth pressure chambers, a first common liquid chamber communicating with the first and second pressure chambers, and a second common liquid chamber communicating with the third and fourth pressure chambers. The first and second pressure chambers and the third and fourth pressure chambers are offset in a second direction perpendicular to the first direction. When the width of the first communication channel in the first direction at a position overlapping with the first nozzle in a plan view toward the nozzle plate is defined as the first width, and the width of the first pressure chamber in the first direction is defined as the pressure chamber width, the first width is greater than or equal to the pressure chamber width. This liquid injection head has a wide communication channel, which helps to suppress the decrease in injection efficiency.

[0080] (2) In the liquid injection head described above, the first width may be greater than the pressure chamber width.

[0081] (3) The first width may be 1.5 times or more the width of the pressure chamber.

[0082] (4) The first width may be twice or less the width of the pressure chamber.

[0083] (5) When the thickness direction of the nozzle plate is defined as the third direction, and the height of the first communication channel in the third direction at the position where it overlaps with the first nozzle in the plan view is defined as the first height, the first width may be greater than or equal to the first height. This liquid injection head allows for reducing the flow resistance of the connecting channel while ensuring the rigidity of the components forming the connecting channel.

[0084] (6) A communication plate is provided on the surface facing the nozzle plate, and when the thickness of the communication plate in the third direction at the position overlapping with the first nozzle in the plan view is defined as the first thickness, the first thickness may be greater than the first height. This liquid injection head allows for maintaining the rigidity of the connecting plate while reducing the flow resistance of the connecting channel.

[0085] (7) The first communication channel may include a portion in the plan view between the first and second pressure chambers and the first nozzle, where the width in the first direction is greater than the first width, and the second width is greater. This liquid spray head allows for increased flow velocity near the nozzle.

[0086] (8) The value obtained by subtracting the first width from the second width may be 0.1 times or more the pressure chamber width.

[0087] (9) The liquid may have pseudoplastic properties. This liquid spray head makes it easier to increase the flow rate near the nozzle and reduce viscosity, thus reducing spraying failures of pseudoplastic ink.

[0088] (10) The first length of the portion having the first width in the second direction may be 4% or more and 30% or less of the total length of the first communication channel in the second direction. This liquid injection head allows for reducing flow resistance up to just before the nozzle, thereby suppressing a decrease in injection efficiency, while also reducing the viscosity of the pseudoplastic liquid near the nozzle.

[0089] (11) The first communication channel may include a portion in the plan view between the first and second pressure chambers and the first nozzle, where the width in the first direction is smaller than the first width, and is a third width. This liquid spray head has shown that the faster the liquid flow velocity, the more likely variations are to occur in the concentration of particles contained in the liquid. Therefore, if the liquid flow velocity directly above the nozzle is high, the concentration of particles in the liquid directly above the nozzle decreases. By widening the flow path directly above the nozzle, the flow velocity directly above the nozzle decreases, making it easier to equalize the concentration of particles in the liquid near the nozzle.

[0090] (12) The value obtained by subtracting the third width from the first width may be 0.1 times or more the pressure chamber width.

[0091] (13) The first length of the portion having the first width in the second direction may be 4% or more and 30% or less of the total length of the first communication channel in the second direction. This liquid spray head allows for the uniform distribution of particles within the liquid.

[0092] (14) The first common liquid chamber may be a flow path for supplying liquid to the first and second pressure chambers, and the second common liquid chamber may be a flow path for recovering liquid from the third and fourth pressure chambers.

[0093] (15) In the plan view, the average value of the width in the first direction of the first communication channel from the first and second pressure chambers to the third and fourth pressure chambers may be equal to or greater than the width of the pressure chamber.

[0094] (16) The first communication channel may have the second direction as the longitudinal direction.

[0095] (17) The first communication channel may be a channel common to the first to fourth pressure chambers.

[0096] (18) The nozzle plate has a second nozzle formed thereon for spraying liquid, and includes fifth and sixth pressure chambers arranged side by side in the first direction, seventh and eighth pressure chambers offset from the fifth and sixth pressure chambers in the second direction and arranged side by side in the first direction, and a second communication channel that extends along the nozzle plate, is connected to the second nozzle and communicates with the fifth to eighth pressure chambers. The first common liquid chamber communicates with the fifth and sixth pressure chambers, and the second common liquid chamber communicates with the seventh and eighth pressure chambers. When the first value is twice the width in the first direction of the partition wall separating the first pressure chamber and the second pressure chamber, the width in the first direction of the partition wall separating the first communication channel and the second communication channel may be greater than or equal to the first value and less than or equal to a second value obtained by adding the pressure chamber width to the first value.

[0097] (19) A liquid spray head according to a second embodiment of the present disclosure comprises a nozzle plate on which a nozzle for spraying liquid is formed; when N is an integer of 3 or more, N pressure chambers A arranged in a line in a first direction; N pressure chambers B arranged in a line in the first direction, offset from the N pressure chambers A in a second direction perpendicular to the first direction; a flow path extending along the nozzle plate, connected to the nozzle and communicating with the N pressure chambers A and the N pressure chambers B; a first common liquid chamber communicating with the N pressure chambers A; and a second common liquid chamber communicating with the N pressure chambers B. When the width of the communication flow path in the first direction at a position overlapping with the nozzle in a plan view toward the nozzle plate is defined as the first width, and the width of the pressure chamber A in the first direction is defined as the pressure chamber width, the first width is greater than or equal to the pressure chamber width.

[0098] (20) In the liquid spray head described above, the first width (W R1 ) is the pressure chamber width (W C1 It may also be defined as being (N-1) times or more and N times or less of ).

[0099] (21) A liquid injection device according to a third embodiment of the present disclosure comprises a liquid injection head and a liquid storage unit for storing liquid to be supplied to the liquid injection head.

[0100] This disclosure can also be implemented in various forms other than liquid injection heads and liquid injection devices. For example, it can be implemented in the form of a method for manufacturing liquid injection heads and liquid injection devices, a method for controlling liquid injection heads and liquid injection devices, a computer program that implements the control method, a non-temporary recording medium that stores the computer program, and so on. [Explanation of symbols]

[0101] 54…Diaphragm, 59…Wiring board, 60…Circulation mechanism, 61…First supply pump, 62…Second supply pump, 63…Storage container, 64…Recovery channel, 65…Supply channel, 70…Drive circuit, 100…Liquid injection head, 110…First common liquid chamber, 120…Second common liquid chamber, 130…Individual nozzle channels, 140…Communication plate, 150…Sealing film, 160…Housing section, 161,162…Opening, 200…Nozzle, 240…Nozzle plate, 250… Pressure chamber substrate, 300, 301~304…Drive element, 310…Diaphragm, 320, 321~324…Connecting channel, 330, 331~334…Pressure chamber, 340, 341~344…Communication hole, 350…Communication channel, 351…First part, 352…Second part, 353…Third part, 400…Liquid injection device, 420…Liquid reservoir, 430…Moving mechanism, 432…Belt, 434…Carriage, 440…Conveying mechanism, 450…Control unit

Claims

1. a nozzle plate in which a first nozzle for ejecting liquid is formed; A first pressure chamber and a second pressure chamber arranged side by side in a first direction; third and fourth pressure chambers arranged side by side in the first direction; a first communication flow path that is a flow path extending along the nozzle plate, is connected to the first nozzle, and is in communication with the first to fourth pressure chambers; a first common liquid chamber communicating with the first and second pressure chambers; a second common liquid chamber communicating with the third and fourth pressure chambers; Equipped with the first and second pressure chambers and the third and fourth pressure chambers are shifted in a second direction perpendicular to the first direction, a width in the first direction of the first communication flow channel at a position overlapping with the first nozzle in a plan view seen toward the nozzle plate is defined as a first width, and a width in the first direction of the first pressure chamber is defined as a pressure chamber width, the first width being equal to or larger than the pressure chamber width. A liquid jet head comprising:

2. The first width is greater than the pressure chamber width. The liquid jet head according to claim 1 .

3. The first width is 1.5 times or more the width of the pressure chamber. The liquid jet head according to claim 1 .

4. The first width is equal to or less than twice the width of the pressure chamber. The liquid jet head according to claim 1 .

5. a thickness direction of the nozzle plate is defined as a third direction, and a height of the first communication flow channel in the third direction at the position overlapping with the first nozzle in the plan view is defined as a first height, the first width being equal to or greater than the first height. The liquid jet head according to claim 1 .

6. a communication plate having the first communication flow path formed on a surface facing the nozzle plate, when a thickness of the communication plate in the third direction at the position overlapping with the first nozzle in the plan view is defined as a first thickness, the first thickness is greater than the first height, The liquid jet head according to claim 5 .

7. the first communication flow path includes a portion, at a position between the first and second pressure chambers and the first nozzle in the plan view, whose width in the first direction is a second width larger than the first width; The liquid jet head according to claim 1 .

8. a value obtained by subtracting the first width from the second width is equal to or greater than 0.1 times the width of the pressure chamber; The liquid jet head according to claim 7 .

9. The liquid has pseudoplastic properties. The liquid jet head according to claim 7 or 8.

10. a first length in the second direction of the portion having the first width is 4% to 30% of the entire length in the second direction of the first communication flow path, The liquid jet head according to claim 7 .

11. the first communication flow path includes a portion, at a position between the first and second pressure chambers and the first nozzle in the plan view, whose width in the first direction is a third width smaller than the first width; The liquid jet head according to claim 1 .

12. a value obtained by subtracting the third width from the first width is equal to or greater than 0.1 times the pressure chamber width; The liquid jet head according to claim 11.

13. a first length in the second direction of the portion having the first width is 4% to 30% of the entire length in the second direction of the first communication flow path, The liquid jet head according to claim 11 or 12.

14. the first common liquid chamber is a flow path for supplying liquid to the first and second pressure chambers, The liquid jet head according to claim 1 , wherein the second common liquid chamber is a flow path for recovering liquid from the third and fourth pressure chambers.

15. an average value of a width in the first direction of the first communication flow passage from the first and second pressure chambers to the third and fourth pressure chambers in the plan view is equal to or greater than a width of the pressure chambers. The liquid jet head according to claim 1 .

16. The first communication flow passage has a longitudinal direction in the second direction. The liquid jet head according to claim 1 .

17. the first communication flow path is a flow path common to the first to fourth pressure chambers; The liquid jet head according to claim 1 .

18. A second nozzle for ejecting liquid is formed in the nozzle plate, Fifth and sixth pressure chambers arranged side by side in the first direction; seventh and eighth pressure chambers arranged side by side in the first direction and offset from the fifth and sixth pressure chambers in the second direction; a second communication flow path that is a flow path extending along the nozzle plate, is connected to the second nozzle, and is in communication with the fifth to eighth pressure chambers; Equipped with the first common liquid chamber communicates with the fifth and sixth pressure chambers, the second common liquid chamber communicates with the seventh and eighth pressure chambers, when a first value is twice the width in the first direction of a partition wall that separates the first pressure chamber and the second pressure chamber, the width in the first direction of the partition wall that separates the first communication flow path and the second communication flow path is equal to or larger than the first value and is equal to or smaller than a second value obtained by adding the width of the pressure chamber to the first value, The liquid jet head according to claim 1 .

19. A nozzle plate in which nozzles for ejecting liquid are formed; N pressure chambers A arranged in a first direction, where N is an integer of 3 or more; N pressure chambers B arranged side by side in the first direction, the N pressure chambers A being shifted from each other in a second direction perpendicular to the first direction; a communication flow path extending along the nozzle plate, the communication flow path being connected to the nozzle and communicating with the N pressure chambers A and the N pressure chambers B; a first common liquid chamber communicating with the N pressure chambers A; A second common liquid chamber communicating with the N pressure chambers B; Equipped with a width of the communication flow channel in the first direction at a position overlapping with the nozzle in a plan view toward the nozzle plate is defined as a first width, and a width of the pressure chamber A in the first direction is defined as a pressure chamber width, the first width being equal to or larger than the pressure chamber width. Liquid injection head.

20. The first width is equal to or greater than (N-1) times and equal to or less than N times the width of the pressure chamber. The liquid jet head according to claim 19.

21. A nozzle plate having nozzles for ejecting liquid formed therein; A first pressure chamber and a second pressure chamber arranged side by side in a first direction; third and fourth pressure chambers arranged side by side in the first direction; a communication flow path extending along the nozzle plate, the communication flow path being connected to the nozzle and communicating with the first to fourth pressure chambers; a first common liquid chamber communicating with the first and second pressure chambers; a second common liquid chamber communicating with the third and fourth pressure chambers; Equipped with the first and second pressure chambers and the third and fourth pressure chambers are shifted in a second direction perpendicular to the first direction, a length in the second direction of a portion of the communication flow passage between the first pressure chamber and the second pressure chamber is equal to or less than a length in the second direction of the first pressure chamber; A liquid jet head comprising:

22. A nozzle plate having nozzles for ejecting liquid formed therein; A first pressure chamber and a second pressure chamber arranged side by side in a first direction; third and fourth pressure chambers arranged side by side in the first direction; a communication flow path extending along the nozzle plate, the communication flow path being connected to the nozzle and communicating with the first to fourth pressure chambers; a first common liquid chamber communicating with the first and second pressure chambers; a second common liquid chamber communicating with the third and fourth pressure chambers; Equipped with the first and second pressure chambers and the third and fourth pressure chambers are shifted in a second direction perpendicular to the first direction, a length in the second direction of a portion of the communication flow path between the first pressure chamber and the second pressure chamber is equal to or less than a width in the first direction of the communication flow path at a position overlapping with the nozzle in a plan view seen toward the nozzle plate. A liquid jet head comprising:

23. A nozzle plate having nozzles for ejecting liquid formed therein; A first pressure chamber and a second pressure chamber arranged side by side in a first direction; third and fourth pressure chambers arranged side by side in the first direction; a communication flow path extending along the nozzle plate, the communication flow path being connected to the nozzle and communicating with the first to fourth pressure chambers; a first common liquid chamber communicating with the first and second pressure chambers; a second common liquid chamber communicating with the third and fourth pressure chambers; Equipped with the first and second pressure chambers and the third and fourth pressure chambers are shifted in a second direction perpendicular to the first direction, The entire length of the communication flow passage in the second direction is equal to or less than the length of the first pressure chamber in the second direction. A liquid jet head comprising:

24. A liquid jet head according to any one of claims 1 to 23, a liquid storage section configured to store a liquid to be supplied to the liquid jet head; A liquid ejection device comprising:

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