JP5530896B2 - Inkjet head and printing apparatus - Google Patents

Description

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

  In an ink jet recording apparatus, by pressurizing ink supplied into an ink pressure chamber of an ink jet head, the ink is ejected as an ink droplet from a nozzle hole, and the ink droplet is attached to a recording medium at a certain distance from the ink jet head. The image is formed.

  Ink used in a color printing type inkjet recording apparatus is generally often cyan, magenta, yellow, and black. In recent years, inkjet systems have been applied to industrial applications, particularly printing of electronic component mounting boards, and white ink may be used as the ink to be used.

  The white ink uses, for example, titanium oxide as a pigment. Such white ink has a larger pigment particle size and a higher specific gravity of the pigment than ordinary color inks such as cyan, magenta, yellow, and black. Further, in this white ink, many pigments are mixed in the ink in order to increase the concealment rate. For this reason, if the ink is allowed to stand for a certain period of time in the path through which the ink flows or in the inkjet head, the pigment settles, causing various problems. For example, the ink density balance is lost, density increases and pigment aggregation occurs, which may cause a problem of non-ejection due to clogging of the nozzles of the inkjet head.

  Therefore, a technique has been proposed in which ink is circulated through an ink jet head and the ink is stirred in an ink tank to suppress sedimentation of pigment in the ink path and in the ink jet head.

JP 2005-246854 A

  An object of the present embodiment is to provide an ink jet head capable of shortening the time required to start printing and a printing apparatus including the ink jet.

According to this embodiment,
An insulating substrate, a piezoelectric member arranged along a first direction at a predetermined interval on one surface of the insulating substrate and extending along a second direction intersecting the first direction, and bonded to the piezoelectric member A nozzle plate having a nozzle hole communicating with the ink pressure chamber, the insulating substrate, the adjacent piezoelectric member, and an ink pressure chamber surrounded by the nozzle plate, the ink pressure chamber being An inkjet head is provided, wherein the first width on the nozzle plate side has a wider cross-sectional shape than the second width on the insulating substrate side in a plane orthogonal to the second direction.

According to this embodiment,
An insulating substrate, a piezoelectric member arranged along a first direction at a predetermined interval on one surface of the insulating substrate and extending along a second direction intersecting the first direction, and bonded to the piezoelectric member And a nozzle plate having a nozzle hole communicating with the ink pressure chamber, the insulating substrate, the adjacent piezoelectric member, and an ink pressure chamber surrounded by the nozzle plate. An ink jet head that discharges the supplied ink from the nozzle holes to form an image on a recording medium; and an ink circulation mechanism that circulates the ink through the ink pressure chamber of the ink jet head. The ink pressure chamber of the head has a first width on the nozzle plate side larger than a second width on the insulating substrate side in a plane orthogonal to the second direction. Printing apparatus is provided which is characterized by having a have cross-sectional shapes.

FIG. 1 is an exploded perspective view schematically showing the configuration of the ink jet head in the present embodiment. FIG. 2 is a diagram schematically illustrating a configuration example of an ink jet recording apparatus which is a printing apparatus according to the present embodiment. FIG. 3 is a cross-sectional view schematically showing a structure including a main part and a nozzle plate constituting the ink jet head of the present embodiment. FIG. 4 is a diagram schematically showing the contour of the inner surface of the ink pressure chamber in a plane orthogonal to the second direction.

  Hereinafter, the present embodiment will be described in detail with reference to the drawings. In each figure, the same reference numerals are given to components that exhibit the same or similar functions, and duplicate descriptions are omitted.

  FIG. 1 is an exploded perspective view schematically showing the configuration of the inkjet head 2 in the present embodiment.

  That is, the inkjet head 2 includes a main part 10, a nozzle plate 20, a mask plate 30, and a holder 40. The inkjet head 2 has a substantially rectangular parallelepiped shape with the first direction X as a longitudinal direction. In the following description, the direction substantially orthogonal to the first direction X is defined as the second direction Y, the direction orthogonal to the XY plane is defined as the third direction Z, and “up” along the third direction Z is defined as The “down” along the third direction Z corresponds to the side away from the recording medium (or the antigravity direction). The direction in which ink droplets are ejected from nozzle holes to be described later is an upward direction along the third direction Z.

  The main part 10 includes an insulating substrate 11, a frame body 12, a piezoelectric member 13, and the like.

  The insulating substrate 11 is made of ceramics such as alumina, for example, and is formed in a substantially rectangular plate shape extending along the first direction X. The insulating substrate 11 has an upper surface (one surface) 11T on the side facing the nozzle plate 20 and a lower surface 11B on the side facing the holder 40. Such an insulating substrate 11 has an ink supply port 11in and an ink discharge port 11out. The ink supply port 11in and the ink discharge port 11out penetrate from the upper surface 11T to the lower surface 11B.

  The frame body 12 is made of metal, for example, and is formed in a rectangular frame shape. The frame body 12 is disposed on the upper surface 11T of the insulating substrate 11. The piezoelectric member 13 is made of, for example, PZT (lead zirconate titanate), and is disposed on the inner surface surrounded by the frame body 12 on the upper surface 11T of the insulating substrate 11. The plurality of piezoelectric members 13 are arranged along the first direction X at a predetermined interval. Each piezoelectric member 13 extends along a second direction Y that intersects the first direction X. Between a pair of adjacent piezoelectric members 13 aligned along the first direction X, an ink pressure chamber 14 extending along the second direction Y is formed in a slit shape or a groove shape.

  In the illustrated example, two rows of piezoelectric members 13 arranged along the first direction X are formed. The plurality of ink supply ports 11in are arranged along the first direction X in the substantially central portion of the insulating substrate 11, that is, between the two rows of piezoelectric members 13. The plurality of ink discharge ports 11out are arranged along the first direction X in the peripheral portion of the insulating substrate 11, that is, between the piezoelectric member 13 and the frame body 12. With such a configuration, ink is supplied from each of the ink supply ports 11in toward the ink pressure chamber 14, and the ink that has passed through the ink pressure chamber 14 is discharged from each of the ink discharge ports 11out. These ink supply port 11in and ink discharge port 11out are connected to an ink circulation path, as will be described later.

  The nozzle plate 20 is made of, for example, a resin such as polyimide, or a metal having heat resistance such as a nickel alloy or stainless steel, and is formed in a substantially rectangular flat plate extending along the first direction X. . The nozzle plate 20 is disposed above the main portion 10 along the third direction Z. The nozzle plate 20 has an upper surface 20T on the side facing the mask plate 30 and a lower surface 20B on the side facing the main portion 10. The lower surface 20B of the nozzle plate 20 is bonded to the frame body 12 and the piezoelectric member 13 with an adhesive (not shown).

  Such a nozzle plate 20 has a nozzle hole 21. Each nozzle hole 21 is formed to face the ink pressure chamber 14 and communicates with the ink pressure chamber 14. These nozzle holes 21 are circular in the XY plane and are formed to have substantially the same diameter.

  The plurality of nozzle holes 21 are arranged substantially along the first direction X, and form nozzle rows 211 and 212. In the illustrated example, two nozzle rows 211 and 212 are formed on the nozzle plate 20, but the nozzle row may be one row or three or more rows. Strictly speaking, the adjacent nozzle holes 21 may not be formed on the same straight line along the first direction X, but detailed description thereof is omitted here.

  The mask plate 30 is made of metal, for example, and is formed in a frame shape surrounding the nozzle plate 20. The mask plate 30 is disposed above the main part 10 along the third direction Z. The mask plate 30 has a rectangular opening 30 </ b> H substantially equal to the outer diameter of the nozzle plate 20. The mask plate 30 and the frame 12 are bonded with an adhesive (not shown).

  The holder 40 is disposed below the main part 10 along the third direction Z. The holder 40 has an upper surface 40T on the side facing the main portion 10. The upper surface 40T of the holder 40 and the lower surface 11B of the insulating substrate 11 are bonded with an adhesive (not shown). Further, the holder 40 has an ink introduction path 41 for introducing ink toward the ink supply port 11in, and an ink collection path 42 for collecting ink discharged from the ink discharge port 11out. An introduction pipe 51 for introducing ink into the holder 40 is connected to the ink introduction path 41. A recovery pipe 52 for recovering ink from the holder 40 is connected to the ink recovery path 42.

  FIG. 2 is a diagram schematically illustrating a configuration example of the ink jet recording apparatus 1 which is the printing apparatus of the present embodiment.

  That is, the ink jet recording apparatus 1 performs printing using various inks on a recording medium. In particular, as the ink, white ink using titanium oxide as a pigment, metal ink using a metal such as copper, silver, or gold as a raw material can be used. The recording medium is not limited to paper, and an electronic component mounting board or the like is applicable.

  The ink jet recording apparatus 1 includes the ink jet head 2, the ink circulation mechanism 3, the ink supply mechanism 4 and the like configured as shown in FIG.

  The ink circulation mechanism 3 circulates ink through the ink pressure chamber 14 of the inkjet head 2 and includes a first sub tank 310, a second sub tank 320, a circulation pump 330, a three-way valve 340, and the like. These are all connected by piping. The ink circulation mechanism 3 forms an ink circulation path through which ink is circulated through the inkjet head 2 in the direction of ink flow indicated by an arrow in the drawing. The inkjet head 2 is connected in the middle of the ink circulation path.

  The first sub tank 310 is located on the upstream side of the inkjet head 2. The first sub tank 310 is controlled to a predetermined pressure. The first sub tank 310 is connected to the introduction pipe 51 of the inkjet head 2 through a pipe. Thereby, the ink supply port 11in of the insulating substrate 11 and the ink circulation mechanism 3 are connected.

  The second sub tank 320 is located on the downstream side of the inkjet head 2. The second sub tank 320 is controlled to a predetermined pressure. The second sub tank 320 is connected to the recovery pipe 52 of the inkjet head 2 through a pipe. Thereby, the ink discharge port 11out of the insulating substrate 11 and the ink circulation mechanism 3 are connected.

  The circulation pump 330 is located downstream of the second sub tank 320 and upstream of the first sub tank 310. Such a circulation pump 330 is constituted by, for example, a diaphragm pump. The three-way valve 340 is located downstream of the circulation pump 330 and upstream of the first sub tank 310. The three-way valve 340 is connected to the ink supply mechanism 4.

  In the ink circulation mechanism 3 having such a configuration, the ink circulates along the ink circulation path as the circulation pump 330 is driven. The ink introduced from the first sub tank 310 is supplied to the inkjet head 2. The supplied ink passes through the introduction pipe 51 and is supplied to the ink pressure chamber 14 from the ink supply port 11 in of the insulating substrate 11 through the ink introduction path 41 of the holder 40.

  A part of the ink supplied to the ink pressure chamber 14 is ejected from the nozzle hole 21 of the nozzle plate 20 toward the recording medium M. The ink that has passed through the ink pressure chamber 14 is discharged from the ink discharge port 11out of the insulating substrate 11, passes through the recovery pipe 52 via the ink recovery path 42 of the holder 40, and is discharged from the inkjet head 2. The discharged ink is collected in the second sub tank 320. The ink collected in the second sub tank 320 circulates through the ink circulation path and is supplied to the first sub tank 310 again.

  The ink supply mechanism 4 supplies ink to the ink circulation mechanism 3, and includes a main tank 410, a filter 420, a main pump 430, and the like.

  The main tank 410 stores ink. The filter 420 is located between the main tank 410 and the main pump 430. The filter 420 removes foreign matters and ink coagulates contained in the ink. The main pump 430 is located between the filter 420 and the three-way valve 340. The main pump 430 is constituted by a diaphragm pump, for example.

  In the ink supply mechanism 4 having such a configuration, when the ink remaining in the ink circulation mechanism 3 falls below a predetermined value as the ink is ejected from the inkjet head 2, the ink circulation mechanism 3 receives ink. Replenish. That is, the main pump 430 is driven and ink is sucked out from the main tank 410. The sucked out ink is supplied to the three-way valve 340 after foreign matters are removed through the filter 420 and introduced into the ink circulation path of the ink circulation mechanism 3.

  Although not described in detail, each of the first sub tank 310 and the second sub tank 320 included in the ink circulation mechanism 3 and the main tank 410 included in the ink supply mechanism 4 includes various stirring devices such as a magnetic stirrer. It has been. By appropriately driving each of such stirring devices, the ink is appropriately stirred in each tank, and sedimentation of pigments and the like in the tank is suppressed.

  FIG. 3 is a cross-sectional view schematically showing a structure including the main part 10 and the nozzle plate 20 constituting the inkjet head 2 of the present embodiment. Here, a cross section in the XZ plane orthogonal to the second direction Y is illustrated.

  That is, the piezoelectric members 13 are arranged at a predetermined interval on the upper surface 11T of the insulating substrate 11. Although detailed description is omitted, the piezoelectric member 13 is formed by stacking, for example, two piezoelectric members whose polarization directions are opposite to each other in the third direction Z. Such a piezoelectric member 13 has a bottom surface 13B in contact with the insulating substrate 11, a top surface 13T in contact with the nozzle plate 20, and a side surface 13S that connects the bottom surface 13B and the top surface 13T. The piezoelectric member 13 is disposed with an ink pressure chamber 14 therebetween.

  The ink pressure chamber 14 is located between two piezoelectric members 13 adjacent to each other. More specifically, the ink pressure chamber 14 is surrounded by the insulating substrate 11, the adjacent piezoelectric member 13, and the nozzle plate 20.

  The electrode 16 is disposed on each side surface 13S of the piezoelectric member 13. That is, each piezoelectric member 13 is sandwiched between two electrodes 16. The electrode 16 is also disposed on the upper surface 11T of the insulating substrate 11 located between the adjacent piezoelectric members 13. Such an electrode 16 is formed by, for example, nickel plating or copper plating.

  The nozzle plate 20 is bonded to the piezoelectric member 13. More specifically, the upper surface 13T of the piezoelectric member 13 and the lower surface 20B of the nozzle plate 20 are bonded with an adhesive. A nozzle hole 21 formed in the nozzle plate 20 communicates with the ink pressure chamber 14. The center of the nozzle hole 21 is located approximately in the middle between the adjacent piezoelectric members 13.

  In such a configuration, when a voltage having a reverse polarity is applied to each electrode 16 sandwiching the piezoelectric member 13, the piezoelectric member 13 is deformed and the volume of the ink pressure chamber 14 is changed (that is, the volume is expanded). Or shrink the volume). As the volume of the ink pressure chamber 14 changes, the ink introduced into the ink pressure chamber 14 is ejected from the nozzle hole 21.

  In the present embodiment, the ink pressure chamber 14 has a cross-sectional shape in which the first width W1 on the nozzle plate 20 side is wider than the second width W2 on the insulating substrate 11 side in a plane orthogonal to the second direction Y. Have. In the illustrated example, the cross-sectional shape of the ink pressure chamber 14 is trapezoidal. For such an ink pressure chamber 14, the nozzle plate 20 side is positioned in the gravity direction, and the insulating substrate 11 side is positioned in the anti-gravity direction.

  Regarding the piezoelectric member 13, in a plane orthogonal to the second direction Y, the third width W <b> 3 of the upper surface 13 </ b> T in contact with the nozzle plate 20 is narrower than the fourth width W <b> 4 of the bottom surface 13 </ b> B in contact with the insulating substrate 11. It has a shape.

  The ink pressure chamber 14 or the piezoelectric member 13 having the shape described above can be formed by, for example, the following manufacturing method.

  First, two piezoelectric members having polarization directions opposite to each other are stacked on the upper surface 11T of the insulating substrate 11 in the third direction Z. Subsequently, the laminated body of piezoelectric members is cut with a blade to form a groove that becomes the ink pressure chamber 14. Such a cutting process is performed using, for example, a slicer or a dicer to which one or a plurality of blades are attached. The blade is, for example, a diamond blade.

  This blade has a trapezoidal cross section substantially equivalent to the ink pressure chamber 14. By inserting such a blade substantially vertically, the piezoelectric member 13 and the ink pressure chamber 14 having the above-described shape are formed. Note that the piezoelectric member 13 and the ink pressure chamber 14 having the above-described shape may be formed by cutting slightly tilted when the blade is inserted.

  Next, the flow of ink in the ink pressure chamber 14 will be described.

  FIG. 4 is a diagram schematically showing the outline of the inner surface 14I of the ink pressure chamber 14 in a plane orthogonal to the second direction Y. As shown in FIG.

  Here, the inner surface 14I of the ink pressure chamber 14 opposes the surface of the electrode 16 covering the upper surface 11T of the insulating substrate 11, the surface of the electrode 16 covering the side surface 13S of the piezoelectric member 13, and the ink pressure chamber 14. This is the lower surface 20 </ b> B of the nozzle plate 20.

  When a viscous liquid such as ink flows in a closed tube, the flow velocity differs between the tube center (tube axis) and the vicinity of the inner wall of the tube, and the flow velocity of the liquid gradually increases from the tube axis toward the inner wall of the tube. Decrease. That is, it can be said that the center of the pipe farthest from the inner wall of the pipe has the highest flow velocity, and the peripheral portion in the pipe closest to the inner wall of the pipe has the lowest flow velocity.

  As shown in FIG. 4A, when the contour of the inner surface 14I of the ink pressure chamber 14 is rectangular (corresponding to a comparative example), the position where the flow velocity of the ink flowing through the ink pressure chamber 14 is the fastest is the inner surface. It is a position farthest from 14I, that is, a position that becomes the center of the ink pressure chamber 14, and is a position indicated by F1 in the drawing. Such a position having the fastest flow velocity may be referred to as a center of gravity.

  On the other hand, as shown in FIG. 4B, consider the case where the contour of the inner surface 14I of the ink pressure chamber 14 is trapezoidal (corresponding to this embodiment). However, the height of the trapezoid at this time is the same as the length of the long side in the comparative example shown in FIG. In the case of the illustrated trapezoid, the length of the upper base is shorter than the length of the lower base, so the position where the flow velocity of the ink flowing through the ink pressure chamber 14 is the fastest is slightly below the position F1 shown in FIG. That is, it is on the lower bottom side and is at the position indicated by F2 in the figure.

  As an example of the dimensions, in the rectangle shown in FIG. 4A, the length of the pair of short sides is 80 μm, and the length of the pair of long sides is 300 μm. Further, in the trapezoid shown in FIG. 4B, the length of the upper base is 72 μm, the length of the lower base is 88 μm, and the height is 300 μm.

  In the present embodiment, the lower bottom corresponds to the lower surface 20B of the nozzle plate 20 and is positioned in the direction of gravity, and the upper bottom corresponds to the surface of the electrode 16 covering the upper surface 11T of the insulating substrate 11 and is antigravity. Located in the direction. The flow rate of the ink flowing through the ink pressure chamber 14 having such a configuration is faster on the side closer to the nozzle plate 20 than on the side of the insulating substrate 11. That is, in the configuration of the present embodiment shown in FIG. 4B, the ink flow velocity is closer to the nozzle plate 20 than in the comparative example shown in FIG. A fast region can be formed.

  In the present embodiment, the contour of the inner surface 14I of the ink pressure chamber 14 is not limited to the trapezoidal shape as shown in FIG. 4B, but as shown in FIG. 4 may be rounded at the intersections between each side, and even in such a shape, the position F3 where the flow velocity of the ink flowing through the ink pressure chamber 14 is the fastest is shown in FIG. Similar to the example shown in (b), it is located on the lower bottom side from the position F1 shown in (a) of FIG.

  As described above, in the present embodiment, when an ink having a relatively high pigment concentration and specific gravity such as white ink is applied, when the printing is resumed after the printing is stopped for a long time, the ink circulation path and the inkjet Even if the pigment has settled in the head 2, by circulating the ink along the ink circulation path by the ink circulation mechanism 3, the settled pigment can be washed away and settling can be eliminated. It is possible to make the pigment concentration uniform.

  Further, in the ink jet head 2, the ink pressure chamber 14 has a side (lower bottom) in which the length of the side (lower base) positioned in the gravitational direction is positioned in the anti-gravity direction in a plane perpendicular to the longitudinal direction, that is, the ink flowing direction. It has a cross-sectional shape longer than the length of the upper base. For this reason, the position where the flow velocity of the ink flowing through the ink pressure chamber 14 is the fastest is the side located in the direction of gravity. That is, in the ink pressure chamber 14, even if the ink has settled on the lower surface 20 </ b> B side of the nozzle plate 20, when the ink circulates, the region where the ink flow velocity is the fastest is the vicinity of the nozzle plate 20, that is, the sediment. It is formed on the side closer to the pigment. As a result, the pigment that has settled in the ink pressure chamber 14 can be removed.

  Further, when the pigment that has settled is removed by circulation of the ink, the pigment that has settled in the ink pressure chamber 14 can be removed in a shorter ink circulation time than in the comparative example. Therefore, the time required to start printing (that is, based on the print start instruction, the stirring operation is performed in the first sub tank 310 and the second sub tank 320, and the circulation pump 330 is driven to circulate the ink in the ink circulation path. And the time until printing by the inkjet head 2 is started can be shortened.

  In the present embodiment, each of the first sub tank 310 and the second sub tank 320 included in the ink circulation mechanism 3 and the main tank 410 included in the ink supply mechanism 4 is provided with a stirring device. For this reason, the settling of the pigment is eliminated by the stirring in each tank, and the pigment is redispersed to improve the ink density balance.

  Further, in the present embodiment, the ink pressure chamber 14 having a trapezoidal cross-sectional shape with respect to the cross-sectional shape of the ink pressure chamber 14 in a plane orthogonal to the second direction uses a blade having a trapezoidal cross-sectional shape. It can be easily formed by cutting the piezoelectric member.

  In addition, although the example which applied the ink containing a pigment was demonstrated here, as above-mentioned, the metal ink etc. which used metals, such as copper, silver, and gold | metal | money, can also be applied, a pigment or comparatively large specific gravity It goes without saying that the same effect can be obtained when various inks containing metals or metal compounds are applied as raw materials.

  As described above, according to the present embodiment, it is possible to provide an ink jet head capable of shortening the time required to start printing and a printing apparatus including this ink jet.

In addition, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.
The invention described in the scope of the claims at the beginning of the present application is added below.
[1]
An insulating substrate;
A piezoelectric member extending along a second direction arranged at a predetermined interval along the first direction on one surface of the insulating substrate and intersecting the first direction;
A nozzle plate having a nozzle hole bonded to the piezoelectric member and communicating with the ink pressure chamber;
The insulating substrate, the adjacent piezoelectric member, and an ink pressure chamber surrounded by the nozzle plate,
The ink-jet head has an ink-jet head having a cross-sectional shape in which a first width on the nozzle plate side is wider than a second width on the insulating substrate side in a plane orthogonal to a second direction.
[2]
The ink jet head according to [1], wherein a cross-sectional shape of the ink pressure chamber is a trapezoidal shape.
[3]
The insulating substrate has an ink supply port through which ink is supplied toward the ink pressure chamber, and an ink discharge port through which ink that has passed through the ink pressure chamber is discharged,
The ink jet head according to [1] or [2], wherein each of the ink supply port and the ink discharge port is connected to an ink circulation path.
[4]
The ink-jet head according to [3], wherein the ink contains a metal or a metal compound.
[5]
The piezoelectric member has a bottom surface in contact with the insulating substrate and a top surface in contact with the nozzle plate, and a third width of the top surface is narrower than a fourth width of the bottom surface in a plane orthogonal to the second direction. The inkjet head according to any one of [1] to [4], which has a trapezoidal cross-sectional shape.
[6]
An insulating substrate, a piezoelectric member arranged along a first direction at a predetermined interval on one surface of the insulating substrate and extending along a second direction intersecting the first direction, and bonded to the piezoelectric member And a nozzle plate having a nozzle hole communicating with the ink pressure chamber, the insulating substrate, the adjacent piezoelectric member, and an ink pressure chamber surrounded by the nozzle plate. An inkjet head that discharges the supplied ink from the nozzle holes and forms an image on a recording medium;
An ink circulation mechanism for circulating ink through the ink pressure chamber of the inkjet head, and
The ink pressure chamber of the inkjet head has a cross-sectional shape in which a first width on the nozzle plate side is wider than a second width on the insulating substrate side in a plane orthogonal to a second direction. apparatus.
[7]
The printing apparatus according to [6], wherein the cross-sectional shape of the ink pressure chamber is trapezoidal.
[8]
The insulating substrate has an ink supply port through which ink is supplied toward the ink pressure chamber, and an ink discharge port through which ink that has passed through the ink pressure chamber is discharged,
The printing apparatus according to [6] or [7], wherein each of the ink supply port and the ink discharge port is connected to the ink circulation mechanism.
[9]
The printing apparatus according to any one of [6] to [8], wherein the ink includes a metal or a metal compound.
[10]
The piezoelectric member has a bottom surface in contact with the insulating substrate and a top surface in contact with the nozzle plate, and a third width of the top surface is narrower than a fourth width of the bottom surface in a plane orthogonal to the second direction. The printing apparatus according to any one of [6] to [9], wherein the printing apparatus has a trapezoidal cross-sectional shape.
[11]
The printing apparatus according to any one of [6] to [10], further comprising an ink supply mechanism that supplies ink to the ink circulation mechanism.
[12]
The printing apparatus according to [11], wherein each of a main tank included in the ink supply mechanism and a sub tank included in the ink circulation mechanism is provided with a stirring device.

DESCRIPTION OF SYMBOLS 1 ... Inkjet recording device 2 ... Inkjet head 3 ... Ink circulation mechanism 4 ... Ink supply mechanism 10 ... Main part 11 ... Insulating substrate 11T ... Upper surface 11B ... Lower surface 11in ... Ink supply port 11out ... Ink discharge port 13 ... Piezoelectric member 13B ... Bottom surface 13T ... Upper surface 13S ... Side surface 14 ... Ink pressure chamber 14I ... Inner surface 16 ... Electrode 20 ... Nozzle plate 20T ... Upper surface 20B ... Lower surface 21 ... Nozzle hole 40 ... Holder 41 ... Ink introduction path 42 ... Ink collection path 51 ... Introducing pipe 52 ... Recovery pipe

Claims (8)

An insulating substrate;
A piezoelectric member extending along a second direction arranged at a predetermined interval along the first direction on one surface of the insulating substrate and intersecting the first direction;
An electrode that covers a side surface of the piezoelectric member and the surface of the insulating member between the piezoelectric members;
A nozzle plate that is bonded to the piezoelectric member and has a nozzle hole that communicates with the ink pressure chamber ;
The ink pressure chamber is surrounded by the electrode and the nozzle plate ;
The ink-jet head has an ink-jet head having a cross-sectional shape in which a first width on the nozzle plate side is wider than a second width on the insulating substrate side in a plane orthogonal to a second direction.   The inkjet head according to claim 1, wherein a cross-sectional shape of the ink pressure chamber is a trapezoidal shape. The insulating substrate has an ink supply port through which ink is supplied toward the ink pressure chamber, and an ink discharge port through which ink that has passed through the ink pressure chamber is discharged,
The inkjet head according to claim 1, wherein each of the ink supply port and the ink discharge port is connected to an ink circulation path.   The inkjet head according to claim 3, wherein the ink contains a metal or a metal compound.   The piezoelectric member has a bottom surface in contact with the insulating substrate and a top surface in contact with the nozzle plate, and a third width of the top surface is narrower than a fourth width of the bottom surface in a plane orthogonal to the second direction. The inkjet head according to claim 1, wherein the inkjet head has a trapezoidal cross-sectional shape. An ink jet head according to any one of claims 1 to 5 ;
An ink circulation mechanism for circulating the ink through the ink pressure chamber of the inkjet head;
Printing apparatus characterized by comprising a. The printing apparatus according to claim 6, further comprising an ink supply mechanism that supplies ink to the ink circulation mechanism. The printing apparatus according to claim 7 , wherein each of a main tank included in the ink supply mechanism and a sub tank included in the ink circulation mechanism includes a stirring device.

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