Search

JP-2026076221-A - droplet dispenser

JP2026076221AJP 2026076221 AJP2026076221 AJP 2026076221AJP-2026076221-A

Abstract

[Problem] To provide an improved piezoelectric droplet ejector for a print head that can achieve a larger number of nozzles. [Solution] The droplet dispenser comprises a substrate having a mounting surface and a nozzle surface on the opposite side; a nozzle forming layer formed on at least a portion of the nozzle surface of the substrate; a fluid chamber defined at least a portion by the substrate and at least a portion by the nozzle forming layer, having a fluid chamber outlet defined at least a portion by the nozzle portion of the nozzle forming layer, wherein the nozzle portion comprises an inner portion located closer to the fluid chamber outlet and an outer portion located closer to the peripheral edge of the nozzle portion; and either or both of the following: an inner actuator mechanism formed on the inner portion of the nozzle portion of the nozzle forming layer and an outer actuator mechanism formed on the outer portion of the nozzle portion of the nozzle forming layer. [Selection Diagram] Figure 2

Inventors

  • マカヴォイ，グレゴリー ジョン

Assignees

  • スリーシー プロジェクト マネージメント リミテッド

Dates

Publication Date
20260511
Application Date
20260115
Priority Date
20180227

Claims (20)

  1. A droplet ejector for a print head, comprising: a substrate having a mounting surface and a nozzle surface on the opposite side; a nozzle forming layer formed on at least a portion of the nozzle surface of the substrate; a fluid chamber defined at least partly by the substrate and at least partly by the nozzle forming layer, having a fluid chamber outlet defined at least partly by the nozzle portion of the nozzle forming layer, wherein the nozzle portion comprises an inner portion located closer to the fluid chamber outlet and an outer portion located closer to the peripheral edge of the nozzle portion; and either or both of the following: an inner actuator mechanism formed on the inner portion of the nozzle portion of the nozzle forming layer, and an outer actuator mechanism formed on the outer portion of the nozzle portion of the nozzle forming layer.
  2. The droplet dispenser according to claim 1, wherein the outer portion of the nozzle portion of the nozzle forming layer at least partially surrounds the inner portion of the nozzle portion of the nozzle forming layer.
  3. The droplet dispenser according to claim 1 or 2, wherein the internal actuator mechanism at least partially surrounds the outlet of the fluid chamber.
  4. The droplet dispenser according to any one of claims 1 to 3, wherein both the internal actuator mechanism and/or the external actuator mechanism are substantially annular.
  5. A droplet dispenser according to any one of claims 1 to 4, further comprising at least one electronic component integrated with the substrate.
  6. A droplet dispenser according to any one of claims 1 to 5, comprising an internal actuator mechanism having one or more internal piezoelectric actuators, wherein at least one of the one or more internal piezoelectric actuators comprises an internal piezoelectric element provided between a pair of internal drive electrodes.
  7. The droplet dispenser according to claim 6, wherein the internal actuator mechanism comprises a single internal piezoelectric actuator that is substantially annular.
  8. A droplet dispenser according to any one of claims 1 to 7, comprising an external actuator mechanism having one or more external piezoelectric actuators, wherein at least one of the one or more external piezoelectric actuators comprises an external piezoelectric element provided between a pair of external drive electrodes.
  9. The droplet ejector according to claim 8, wherein the external actuator mechanism comprises a single external piezoelectric actuator that is substantially annular.
  10. The droplet dispenser according to claim 9, dependent on claim 7, wherein the single outer piezoelectric actuator surrounds the single inner piezoelectric actuator.
  11. Both the pair of inner drive electrodes and the pair of outer drive electrodes are electrically connected to the drive circuit, and when the drive circuit is connected to a power source during use, a first A droplet dispenser according to any one of claims 8 to 10, dependent on claim 6, configured to apply a potential difference to cause deflection of the inner piezoelectric body in a first direction, and to apply a second potential difference between the pair of outer electrodes to cause deflection of the outer piezoelectric body in a second direction opposite to the first direction.
  12. One or more of the inner piezoelectric elements and/or one or more of the outer piezoelectric elements, A droplet dispenser according to any one of claims 6 to 11, comprising one or more piezoelectric materials that can be processed at a temperature of less than 450°C.
  13. One or more of the inner piezoelectric elements and/or one or more of the outer piezoelectric elements, A droplet dispenser according to any one of claims 6 to 12, comprising one or more types of piezoelectric materials that can be deposited at a temperature of less than 450°C.
  14. Claim 12 or 1, wherein the one or more types of piezoelectric materials are PVD-deposited piezoelectric materials. The droplet dispenser described in 3.
  15. The droplet dispenser according to any one of claims 12 to 14, wherein the one or more piezoelectric materials include aluminum nitride and/or zinc oxide.
  16. The droplet dispenser according to claim 15, wherein the aluminum nitride further comprises one or more of the following elements: scandium, yttrium, titanium, magnesium, hafnium, zirconium, tin, chromium, and boron.
  17. A droplet dispenser according to any one of claims 12 to 16, wherein the one or more piezoelectric materials include aluminum and nitrogen, and a ceramic material comprising one or more elements optionally selected from scandium, yttrium, titanium, magnesium, hafnium, zirconium, tin, chromium, and boron.
  18. The droplet dispenser according to any one of claims 12 to 17, wherein the one or more types of piezoelectric materials are non-ferroelectric piezoelectric materials.
  19. One or more of the inner piezoelectric elements and/or one or more of the outer piezoelectric elements, A droplet dispenser according to any one of claims 6 to 18, having a piezoelectric constant d 31 having a magnitude of less than 20 pC/N.
  20. A droplet dispenser according to any one of claims 1 to 19, further comprising at least one electronic component integrated with the substrate.

Description

The present invention relates to a droplet ejector for a print head, and a print head equipped with a droplet ejector, This invention relates to a printer equipped with a printhead that includes a droplet ejector, and to a method for operating the droplet ejector for the printhead. Inkjet printers are used to reproduce digital images on a printing medium (such as paper) by pushing droplets of ink onto the medium. Many inkjet printers incorporate "drop-on-demand" technology, in which a series of individual ink droplets are ejected from the inkjet nozzles of the print head. The ink droplets are ejected with sufficient momentum to adhere to the medium. Each droplet is ejected according to an applied drive signal, which differentiates drop-on-demand inkjet printers from continuous inkjet devices, where a continuous flow of ink droplets is produced by pressurizing ink through fine nozzles. The two most commercially successful drop-on-demand technologies are thermal inkjet printers and piezo (piezoelectric) inkjet printers. In thermal inkjet printers, the printing fluid needs to contain volatile components such as water. A heating element causes spontaneous nucleation of bubbles in the volatile fluid within the print head, forcing droplets of the fluid to be ejected through the nozzle. Piezoelectric inkjet printers, on the other hand, incorporate piezoelectric actuators within the walls of the fluid chamber. Deformation of the piezoelectric element causes the piezoelectric actuator to flex, which induces a pressure change in the printing fluid stored in the fluid chamber, thereby ejecting droplets through the nozzle. Thermal inkjet printers can only be used to eject very small amounts of printing fluid (because the fluid must have proper volatility). Thermal inkjet printers can also experience cogation, where dried ink residue accumulates on the heating element, which shortens the printer's usable lifespan. Piezo-inkjet printers can be used with a wide range of fluids and have a longer operating life than thermal inkjet printers because they do not coagulate. However, compared to thermal inkjet printheads, existing piezoelectric technology can typically only achieve a very small number of nozzles per printhead. This is a diagram of a monolithic fluid droplet dispensing device including an integrated fluid element (fluidics), electronic circuit, nozzle, and actuator according to a first embodiment.Figure 1 is a cross-sectional view of a monolithic droplet dispenser device along line F2.Figure 1 is a plan view of the nozzle, showing the features of the monolithic droplet dispenser with the protective coating removed.Figure 1 is a schematic diagram of an embodiment of the drive pulse for the droplet dispensing device.Figure 1 is a schematic diagram of the manufacturing process flow for the droplet dispensing device.This is a cross-sectional view showing an alternative embodiment of the electrode structure according to a second embodiment of the present invention.This is a schematic diagram showing an alternative drive pulse embodiment for the droplet dispensing device shown in Figure 6.This is a schematic diagram showing a cross-section of an alternative embodiment of the nozzle structure according to a third embodiment of the present invention.This is a cross-sectional view showing an alternative embodiment of the bond pad structure according to a fourth embodiment of the present invention.This is a cross-sectional view through the nozzle structure of any of the droplet dispensing devices shown in Figures 1, 6, 8, or 9 during operation.This invention provides both a cross-sectional view and a plan view showing an alternative monolithic droplet dispenser having only an internal actuator mechanism according to a fifth embodiment of the present invention.Figure 11 is a cross-sectional view showing the nozzle structure of the droplet dispensing device during operation.This invention provides both a cross-sectional view and a plan view showing an alternative monolithic droplet dispenser having only an external actuator mechanism according to a sixth embodiment of the present invention.Figure 13 is a cross-sectional view of the nozzle structure of the droplet dispensing device during operation.This plot shows the volume swept by the diaphragm of the droplet ejector device according to the position of the actuator mechanism.Figures 1, 6, 8, 9, 11, and 13 show the 3D shape of the diaphragm of the droplet ejector device during operation.This plot shows the deflection of the droplet dispenser diaphragm for four different operating embodiments.This plot shows the deflection of the droplet ejector diaphragm for two different actuator configurations, depending on the position of the actuator mechanism on the diaphragm.It is not mentioned in the original text. A first embodiment will be described with reference to Figures 1 to 5 and Figures 10 and 11. Figure 1 shows a monolithic fluid droplet dispensing device 1, which includes