JP4377712B2 - Printing head and printing method - Google Patents

Description

  The present invention relates to a print head mounted on an ink jet printer used for printing characters and images using a piezoelectric actuator and a printing method.

  In recent years, with the spread of personal computers and the development of multimedia, the use of ink jet recording apparatuses as recording apparatuses that output information to recording media is rapidly expanding.

  Such an ink jet recording apparatus is equipped with a print head, and this type of print head includes a heater as a pressurizing unit in an ink flow path filled with ink, and heats the ink with the heater. The thermal method of boiling and pressurizing ink with bubbles generated in the ink flow path, and discharging it as an ink flow from the ink discharge hole, and bending displacement of a part of the wall of the ink flow path filled with ink by a displacement element In general, a piezoelectric method is known in which ink in an ink flow path is mechanically pressurized and discharged as an ink flow from an ink discharge hole.

  In a print head using a piezoelectric method, for example, an actuator having a plurality of pressure generation units is placed on a substrate provided with a plurality of pressure chambers so that one pressure generation unit abuts on one pressure chamber. There has been proposed a print head bonded to the substrate (Patent Document 1).

Since this pressure generating unit can be controlled independently, by discharging the ink filled in the pressurizing chamber using the pressure generated by the vibration in each pressure generating unit, the high speed of the ink jet printer It can contribute to improvement and high accuracy.
JP, 11-34321, A FIG. 1, FIG.

  However, recent high-precision printers require high-density and high-precision arrangement of the ink discharge holes in response to the demand for high-quality printed images. It is required to arrange in density.

When the density is increased in this way, the width of the partition wall becomes narrow, and even when the shape of the piezoelectric generating part is not uniform, the vibration to the adjacent pressure generating part is affected. Further, even if a shape is uniform, since the influence on the vibration of the pressure generating portion which vibration generated by the pressure generating unit are adjacent, stress difference occurs between the piezoelectric generator, this difference can not be neglected, When the print head described in Patent Document 1 is mounted on a printer and ink is ejected, there is a problem that the quality of printing is deteriorated, and in particular, the image quality of the peripheral portion is deteriorated.

  Therefore, an object of the present invention is to provide a print head and a printing method using the same, in which the deterioration of image quality is improved even when the pressure generating portions are formed with high density.

  In the present invention, when the pressurization chamber is configured with high density, among the pressurization chambers provided on the substrate in a large number, the outermost pressurization chamber and the pressurization chamber in the inside thereof, the ink discharge amount, the discharge pressure, etc. Therefore, it has been found that the image quality of the peripheral portion is lowered due to the difference, and the provision of a dummy cavity on the outer periphery of the pressurization chamber has significantly improved the image quality degradation.

That is, the print head according to the present invention includes a pressure generating unit on a main surface of a substrate provided with a plurality of pressure chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink are connected. The plurality of actuators are arranged so that the pressure chambers are in contact with each of the pressure generating portions, and the substrate on the outer periphery of the plurality of pressure chambers does not have ink discharge holes. The dummy cavity is formed, and the actuator covers the dummy cavity, the pressurizing chamber, a partition wall between the pressurizing chamber, and a partition wall between the pressurizing chamber and the dummy cavity. Features.
In addition, the print head of the present invention includes a pressure generator on a main surface of a substrate provided with a plurality of pressure chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink are connected. A plurality of actuators are provided so that the pressurizing chambers are in contact with each of the pressure generating parts, and the pressure generating part includes a surface electrode, a common electrode, the common electrode, and the surface electrode. A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, and the actuator is provided with surface electrodes corresponding to the dummy cavities. The actuator covers the dummy cavity, the pressurizing chamber, a partition wall between the pressurizing chamber, and a partition wall between the pressurizing chamber and the dummy cavity. .
Furthermore, the print head according to the present invention includes a pressure generating unit on a main surface of a substrate provided with a plurality of pressurizing chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink are connected. A plurality of actuators are provided so that the pressurizing chambers are in contact with each of the pressure generating parts, and the pressure generating part includes a surface electrode, a common electrode, the common electrode, and the surface electrode. A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, and the actuator is connected to the outside corresponding to the dummy cavities. The surface electrode is not provided, and the actuator includes the dummy cavity, the pressurizing chamber, a partition wall between the pressurizing chamber, and a partition wall between the pressurizing chamber and the dummy cavity. Tsu, characterized in that is.

  By adopting such a configuration, the influence of all the pressurizing chambers on the adjacent pressurizing chambers can be made uniform, so that the displacement of the piezoelectric layer in the pressure generating section can be made uniform. Specifically, since the pressure generating part corresponding to the pressurizing chamber is superior and uniform in piezoelectric characteristics than the pressure generating part corresponding to the dummy cavity, the variation in ink discharge amount and discharge pressure is improved. Printing with high image quality can be realized.

  In particular, the shape of the pressurizing chamber and the shape of the dummy cavity are preferably substantially the same. Thus, by making the shape the same, it becomes easy to make the displacement of the piezoelectric layer in each pressure generating part more uniform.

The distance between the pressurized chamber adjacent to the dummy cavity and the dummy cavity is preferably a distance substantially the same between the front Symbol pressurizing chamber. Thus, by increasing the symmetry, it is possible to further increase the uniformity of the displacement of the piezoelectric layer in each pressure generating portion.

Further, it is preferable arrangement of the other of said pressure chamber and said dummy cavities adjacent to one said pressurizing chamber is approximately the same for all of the pressure chamber. Thereby, the symmetry of each pressurizing chamber can be enhanced, and the uniformity of displacement of the piezoelectric layer in each pressure generating portion can be more reliably enhanced.

  Furthermore, it is preferable that the dummy cavity can be filled with ink. With such a configuration, it becomes possible to fill the dummy cavities with ink, and it is possible to further improve the symmetry and further improve the uniformity of the displacement of the piezoelectric layer in each pressure generating portion.

  Furthermore, it is preferable that a surface electrode corresponding to the dummy cavity is provided, and a voltage is not substantially applied to the surface electrode. This makes it easy to prevent the ink filled in the dummy cavity from being accidentally discharged and preventing the image quality from being deteriorated.

Further, the printing method of the present invention includes a pressure generating portion on a main surface of a substrate provided with a plurality of pressure chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink are connected. A plurality of actuators are provided so that the pressurizing chambers are in contact with each of the pressure generating parts, and the pressure generating part includes a surface electrode, a common electrode, the common electrode, and the surface electrode. A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, and a surface electrode corresponding to the dummy cavities is formed on the actuator, the actuator using the dummy cavities, said pressure chamber, the print head that covers the partition wall located between said dummy cavity between the partition and the pressure chamber located between said pressure chamber, said da No voltage is applied to the surface electrodes corresponding to the over cavity, by applying a voltage to the surface electrode of the pressure generating portion, characterized in that the ink is ejected from the pressure chamber, by which, the high-quality printing Can be realized.

  According to the present invention, by providing the dummy cavity on the outer periphery of the pressurizing chamber provided on the substrate, the displacement of the pressure generating portion corresponding to the pressurizing chamber can be made uniform. By avoiding ink ejection and ejecting ink from the pressurizing chamber disposed therein, it is possible to suppress deterioration in image quality particularly in the peripheral portion.

  The actuator of this invention is demonstrated using figures.

  FIG. 1 shows an embodiment of a print head according to the present invention. As shown in FIG. 1A, an actuator 2 is provided on the main surface of a substrate 1.

A plurality of pressurizing chambers 4 are provided on the substrate 1, and the pressurizing chambers 4 are separated by partition walls 5. Further, as will be described later, the actuator 2 includes a plurality of pressure generating units 17, and the pressurizing chambers 4 are arranged so as to abut each of the pressure generating units 17. A dummy cavity 6 is provided on the outer periphery of the plurality of pressurizing chambers 4. The actuator 2 includes a dummy cavity 6, a pressurizing chamber 4, a partition wall 5 between the pressurizing chamber 4, a pressurizing chamber 4 and a dummy. It is important to cover the partition wall 5 between the cavity 6 .

  The pressurizing chamber 4 needs to be connected to an ink flow path (not shown) for introducing ink and an ink discharge hole 3 for discharging ink. The pressurizing chamber 4 may form a part of the ink flow path, but in any case, after the ink is ejected, the ink flows into the pressurizing chamber 4 to replenish the ink, and the pressurizing chamber 4 is always pressurized. It is important to have a mechanism for filling the chamber 4 with ink.

  As shown in FIG. 1, it is preferable that all the pressurizing chambers 4 have the same shape and are arranged at a constant period. Thereby, it becomes easy to improve symmetry and make the pressure distribution in the pressurizing chamber 4 uniform.

  The shape of the pressurizing chamber 4 may be a rectangle as shown in FIG. 1, a square, a rhombus, a parallelogram, a circle, an ellipse, a polygon, a shape obtained by deforming these shapes, or other shapes. Can be adopted. Here, what is deformed means, for example, a straight line replaced with a gentle curve as shown in FIG. 2A or a rounded corner as shown in FIG. 2B.

  The shape of the pressurizing chamber 4 and the shape of the dummy cavity 6 are preferably substantially the same. Further, it is preferable that the interval between the dummy cavity 6 and the pressurizing chamber 4 adjacent to the dummy cavity 6 is substantially the same as the interval between the plurality of pressurizing chambers 4. Furthermore, it is preferable that the shape and arrangement of the pressurizing chamber 4 and / or the dummy cavity 6 adjacent to one pressurizing chamber 4 are substantially the same for all the pressurizing chambers 4.

  With such a configuration, it becomes easy to make the displacement of the piezoelectric layer in each pressure generating portion more uniform, and as a result, the variation in ink discharge amount and discharge pressure is further reduced, and the print quality is further improved. It becomes easy.

  The number of pressurizing chambers 4 is not particularly limited, and can be designed to a desired size and density based on a desired resolution. Moreover, the size of the substrate 1 can be a desired size. It is preferable that the width of the substrate 1 of the print head of the present invention is set to the same length as the width of A4 paper or A3 paper, for example, so that it can be applied to a line printer and high speed printing can be realized.

  The actuator 2 includes a piezoelectric layer 14, a common electrode 15 provided on one main surface of the piezoelectric layer 14, and a plurality of surface electrodes 16 provided on the other main surface of the piezoelectric layer 14. The piezoelectric layer 14 is sandwiched between the common electrode 15 and the surface electrode 16. Further, when the actuator 2 is provided on the substrate, one of the pressurizing chambers 4 is disposed in contact with each of the surface electrodes 16.

  The actuator 2 is provided with a large number of pressure generating portions 17 because a region substantially the same as the one pressurizing chamber 4 in the actuator 2 acts as one pressure generating portion 17. Further, by arranging one pressure generating unit 17 so as to contact one pressurizing chamber 6, the pressure generated from the pressure generating unit 17 and the accompanying shock wave are transmitted to the ink, and the ink is efficiently ejected. be able to.

  Since the displacement of each pressure generating portion 17 can be increased by reducing the thickness of the actuator 2, it is preferably 100 μm or less, particularly 80 μm or less, more preferably 60 μm or less, and more officially 50 μm or less. . The thickness of the actuator 2 is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 20 μm or more so as not to be too thin and damaged.

  A plurality of surface electrodes 16 are provided on the piezoelectric layer 14. For example, as shown in FIG. 1B, the surface electrodes 16 are two-dimensionally arranged at equal intervals, and are independent of an external electronic control circuit. When the voltage is applied between the electrodes, the piezoelectric layer 14 at the portion sandwiched between the common electrode 15 and the surface electrode 16 to which the voltage is applied is displaced, that is, the pressure generating unit 17 vibrates. Then, pressure is generated in the ink filled in the pressurizing chamber, and ink is ejected from the ink ejection holes 3 by the pressure and / or shock wave generated at that time.

  With respect to the structure of the substrate 1, conventionally, since the dummy cavity 6 is not provided, the ink is discharged between the ink discharged from the outermost pressurizing chamber 4 and the ink discharged from the inner pressurizing chamber 4. The discharge amount, the discharge speed, the discharge pressure, the ink droplet shape, and the like are different, and printing causes a deterioration in the image quality of the peripheral portion. However, according to the present invention, this problem can be improved by providing the dummy cavity 6 on the outer periphery of the pressurizing chamber 4 provided on the substrate 1.

  In the present invention, it is preferable that the dummy cavity 6 provided on the outer periphery of the pressurizing chamber 4 can be filled with ink. That is, the ink tank or the ink flow path is preferably connected to the dummy cavity 6.

As a result, ink can be filled into the dummy cavity 6, and the state of the dummy cavity 6 becomes closer to the state of the pressure chamber 4 filled with ink, so that the symmetry of the pressure chamber 4 adjacent to the dummy cavity 6 is increased. Can be made the same as the symmetry of the pressurizing chamber 4 adjacent to the pressurizing chamber 4 alone, and the uniformity of printing can be further improved.

  Further, a surface electrode corresponding to the dummy cavity 6, that is, a surface electrode provided immediately above the dummy cavity 6 may be provided as the dummy electrode 16b. However, it is necessary to prepare a mechanism that prevents the ink filled in the dummy cavity 6 from being used for printing.

  For this purpose, for example, it is preferable not to provide the ink ejection holes 3 as shown in FIG. In this way, it is possible to reliably prevent ink ejection by disabling ink ejection.

  In addition, an ink discharge hole 3 and a dummy electrode 16b are provided, and the dummy electrode 16b is applied to the dummy electrode 16b by electronic control such as a method of not connecting to a power source or computer control so that no voltage is applied to the dummy electrode 16b. It is also possible to adopt a method in which the voltage is always set to zero. Alternatively, a method of providing an ink removal plate or the like so that the ejected ink does not land on the printing paper may be employed.

  Note that the actuator 2 may have any system and configuration as long as one pressure generating unit 17 is formed for one pressurizing chamber 4. For example, in FIG. 1, the piezoelectric layer 14 can use the vibration mode d31, but other vibration modes may be used.

  Therefore, the substrate 1 is preferably made of a metal material such as stainless steel or 4-2 alloy (alloy), particularly a highly rigid metal, from the viewpoint of reliability against vibration and deformation. Moreover, resin can also be used at a low cost.

  The substrate 1 and the actuator 2 can be joined via an adhesive layer. That is, an adhesive layer is provided at the contact portion with the partition wall 5, and the contact portion with the pressurizing chamber 4 is joined without providing an adhesive layer. Thereby, the displacement is not generated in the non-pressure generating portion of the actuator 2 in contact with the partition wall 5, and the displacement is generated in the pressure generating portion 17 in contact with the pressurizing chamber 4.

  It is important that the piezoelectric layer 14 is mainly composed of a perovskite crystal containing at least Pb, Zr and Ti. For example, a crystal containing Pb as an A site constituent element and Zr and Ti as a B site constituent element, particularly a lead zirconate titanate compound (PZT) having a higher d constant. It is preferable to obtain a stable piezoelectric sintered body having

The piezoelectric strain constant used as the ink jet print head is, for example, d _{31. In} order to exhibit a sufficient discharge capability as the ink jet print head, the size of d ₃₁ is preferably set to 100 pm / V or more. Further, in order to obtain fine printing at high speed, it is more preferable that d ₃₁ is 150 pm / V or more, and further 200 pm / V or more.

  The material of the surface electrode 16 and the common electrode 15 may be any material as long as it has conductivity, and Au, Ag, Pd, Pt, Cu, Al, alloys thereof, and the like are used. For example, the surface electrode 16 can use at least one of Au, Ag, and Cu, and the common electrode 15 can employ an alloy of silver and palladium, or a low resistance metal such as Au, Ag, or Cu. By combining such an electrode with the piezoelectric layer 14 made of PZT, it is possible to reduce the residual compressive stress of the actuator and to suppress a decrease in stress after substrate bonding.

Further, the thicknesses of the surface electrode 16 and the internal electrode 15 need to be conductive and do not hinder displacement, and are generally about 0.1 to 5 μm, and the surface electrode 16 has a thickness of 0.1 to 1 μm. m , particularly 0.3 to 0.7 μm, and the internal electrode 15 is preferably 1 to 4 μm, particularly 1.5 to 3.5 μm.

  FIG. 3 shows another example of the print head of the present invention. That is, the actuator 22 has a structure in which a common electrode 35 is provided on the surface of the ceramic substrate 33, a piezoelectric layer 34 is provided on the common electrode 35, and a plurality of surface electrodes 36 are provided on the piezoelectric layer 34. Yes. This actuator 22 is provided on the substrate 21.

  In other words, the actuator 22 is configured to sandwich the piezoelectric layer 34 between the common electrode 35 and the surface electrode 36, and the common electrode 35 is provided on the ceramic substrate 33.

  In particular, it is preferable that the ceramic base 33 and the piezoelectric layer 34 have substantially the same composition in order to increase the reliability of the actuator 22. Such a structure in which an electrode layer made of a metal is inserted into the piezoelectric layer 34 is difficult to break even if the deformation amount of the piezoelectric layer 34 is increased, and it is effective to destroy the actuator 22 during handling and use. It has an effect that can be prevented.

  According to the present invention, it is preferable to provide the surface electrode 36 corresponding to the pressurizing chamber 24 and not to provide the surface electrode corresponding to the dummy cavity 26. With such a structure, ink filled in the dummy cavity 26 is not ejected, and it becomes easy to prevent a printing error that ink is ejected from the dummy cavity 26.

  In this case, it is preferable that an ink flow path is connected to the dummy cavity 26 and the dummy cavity can be filled with ink. Thereby, there exists an effect which improves the symmetry of the pressurization chamber 24 more.

  By adopting such a highly symmetric configuration, the magnitude of displacement can be controlled independently and sufficiently in each of the pressure generating portions 37 of the actuator 22, and the ink ejection amount can be precisely controlled. Therefore, it is possible to provide a print head with high accuracy, high quality, and little deterioration in image quality in the peripheral portion.

Next, the manufacturing method of the actuator of the present invention will be described by taking as an example a case where a PbZrTiO ₃ -based perovskite crystal is used.

First, Pb ₂ O ₃ , ZrO ₂ , TiO ₂ , BaCO ₃ , ZnO, SrCO ₃ , Sb ₂ O ₃ , NiO, and TeO ₂ are prepared as raw material powders. These are adjusted to a composition in which Pb is added so as to be larger than the Pb amount corresponding to the stoichiometric composition of the perovskite crystal and mixed.

  The obtained mixed powder is molded into a tape made of a piezoelectric ceramic and an organic composition by a general tape molding method such as a roll coater method or a slit coater method to produce a green sheet.

  A surface electrode and a common electrode are formed on a part of the green sheet by a printing method or the like. If desired, a via hole is formed in a part of the green sheet, and a via conductor is inserted into the via hole.

  Next, a desired green sheet is laminated to produce a laminate, and further, a constraining sheet made of a piezoelectric ceramic and an organic composition having substantially the same composition as the green sheet is disposed on both sides or one side of the laminate, Apply pressure contact. The laminate after pressure contact is placed inside a firing furnace and fired.

  The obtained actuator is bonded to a stainless steel substrate using an adhesive. At this time, it is important to arrange the surface electrode so as to contact the pressurizing chamber. In this way, a print head as shown in FIG. 1 or FIG. 3 can be produced.

  The printing method of the present invention is performed using the above-described print head, and does not eject ink from a dummy cavity provided on the outer periphery of the print head, but causes ink to be ejected from a pressure generation unit disposed inside. It is a feature.

  As a method for preventing ink from being ejected, it is possible to use a method in which no surface electrode is provided, no ink ejection hole is provided, the surface electrode is not connected to a power source, or the pressure chamber is not filled with ink.

  By adopting such a configuration, high-quality printing can be performed even if the pressure chamber is high density. In addition, it can easily cope with high-speed and high-precision printing.

  In the arrangement of FIG. 1B, displacement (W), compliance (Cv), and generated pressure (Kp) in the internal pressurizing chamber (another pressurizing chamber is adjacent to the surrounding) and the dummy cavity at the corner. Was calculated by computer simulation based on the finite element method.

  In the modeling, the adjacent pressurizing chambers considered eight surrounding pressurizing chambers in the case of the pressurizing chamber, and three surrounding pressurizing chambers in the case of the dummy cavity at the corner.

  W was defined as the amount of deflection of the central portion in the thickness direction of the pressure generating portion (actuator) toward the pressurizing chamber when a voltage of 20 V was applied.

  Cv is a parameter representing the softness of the diaphragm, and Kp is a parameter representing the pressure generated in the ink chamber when a unit voltage is applied to the actuator. Both indicate the performance of the actuator that generates pressure in the pressurizing chamber. Specifically, the ink discharge speed is determined. When both Cv and Kp become small, the discharge speed decreases.

  As a result of the analysis, Cv, W, and Kp of the pressure generating unit corresponding to the dummy cavity are respectively 8%, 9%, and 6% lower than Cv, W, and Kp of the pressure generating unit corresponding to the pressurizing chamber. It was. On the other hand, Cv and Kp of the pressure generating part corresponding to the pressurizing chamber both had the same value.

  Therefore, although the ink ejection speed in all the pressurizing chambers is uniform, the ink ejection speed from the dummy cavities decreases and becomes non-uniform. Was found to be disturbed. In addition, it was found that the provision of the dummy cavity can improve the deterioration of the image quality in the peripheral portion.

1 shows an example of a print head of the present invention, where (a) is a schematic cross-sectional view, (b) is a plan view seen from the actuator side, and (c) is a schematic cross-section of another print head of the present invention having a different actuator structure. FIG. The shape of the pressurizing chamber which comprises the printing head of this invention is shown, (a) replaces a straight line with the curve, (b) rounds off a corner. The other example of the printing head of this invention is shown, (a) is a schematic sectional drawing, (b) is the top view seen from the actuator side.

Explanation of symbols

1, 2 ... substrate 2, 22 ... actuator 3, 23 ... ink ejection hole 4, 24 ... pressurizing chamber 5, 25 ... partition 6, 26 ... dummy cavity 14, 14b 34 ... Piezoelectric layers 15, 35 ... Common electrodes 16, 36 ... Surface electrodes 16b ... Dummy electrodes 17, 37 ... Pressure generating part 33 ... Ceramic substrate

Claims (9)

An actuator having a plurality of pressure generating portions on a main surface of a substrate provided with a plurality of pressurizing chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink is connected, A plurality of dummy cavities not provided with ink ejection holes are formed on the substrate on the outer periphery of the plurality of pressure chambers, the pressure chambers being disposed so as to abut each of the generating portions, and the actuator Covers the dummy cavity, the pressurizing chamber, the partition wall between the pressurizing chamber and the partition wall between the pressurizing chamber and the dummy cavity. An actuator having a plurality of pressure generating portions on a main surface of a substrate provided with a plurality of pressurizing chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink is connected, The pressurizing chambers are arranged so as to abut each of the generating portions, and the pressure generating portion is a surface electrode, a common electrode, and a piezoelectric layer sandwiched between the common electrode and the surface electrode, A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, and the actuator is not provided with a surface electrode corresponding to the dummy cavities; A print head comprising: a cavity, the pressurizing chamber, a partition wall between the pressurizing chamber, and a partition wall between the pressurizing chamber and the dummy cavity. An actuator having a plurality of pressure generating portions on a main surface of a substrate provided with a plurality of pressurizing chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink is connected, The pressurizing chambers are arranged so as to abut each of the generating portions, and the pressure generating portion is a surface electrode, a common electrode, and a piezoelectric layer sandwiched between the common electrode and the surface electrode, A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, and the actuator is provided with a surface electrode corresponding to the dummy cavities and not connected to the outside, The actuator covers the dummy cavity, the pressurizing chamber, a partition wall between the pressurizing chamber, and a partition wall between the pressurizing chamber and the dummy cavity. Head. 4. The print head according to claim 2, wherein the dummy cavity does not include an ink discharge hole. Print head according to any one of claims 1 to 4, characterized in that shapes of said dummy cavity of the pressure chamber are substantially the same. The distance between the pressurizing chamber adjacent to the dummy cavity with said dummy cavity, print head according to any one of claims 1 to 5, characterized in that said is substantially the same as the spacing between the pressure chamber . According to any one of claims 1 to 6, characterized in that arrangement of the other of said pressure chamber and said dummy cavities adjacent to one said pressurizing chamber is approximately the same for all of the pressure chamber Print head. The print head according to claim 1 to 7, characterized in that the dummy cavities may be filled with ink. An actuator having a plurality of pressure generating portions on a main surface of a substrate provided with a plurality of pressurizing chambers to which an ink flow path for introducing ink and an ink discharge hole for discharging ink is connected, The pressurizing chambers are arranged so as to abut each of the generating portions, and the pressure generating portion is a surface electrode, a common electrode, and a piezoelectric layer sandwiched between the common electrode and the surface electrode, A plurality of dummy cavities are formed in the substrate on the outer periphery of the plurality of pressurizing chambers, a surface electrode corresponding to the dummy cavities is formed in the actuator, the actuator includes the dummy cavities, table pressure chamber, using a print head that covers the partition wall located between said dummy cavity between the partition and the pressure chamber located between said pressure chamber, corresponding to the dummy cavity Without adding a voltage to the electrode, by applying a voltage to the surface electrode of the pressure generating unit, the printing method characterized by discharging ink from the pressure chamber.

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