Micro-droplet ejection unit and micro-droplet ejection device

Abstract

The present invention discloses a micro-droplet injection unit and a corresponding micro-droplet injection unit. A pressure chamber, a liquid inlet channel, and a liquid outlet channel are provided in a pressure chamber base layer of the micro-droplet injection unit, a liquid inlet port and a liquid outlet port are provided in an encapsulation protective layer, and the liquid inlet channel at the liquid inlet end and the liquid outlet channel at the liquid outlet end are respectively open to the side of the pressure chamber. Among them, the liquid inlet channel and the liquid outlet channel and the pressure chamber, the liquid inlet port and the liquid inlet channel, and the liquid outlet port and the liquid outlet channel are respectively extended and connected to each other in a direction at a certain angle, so that the ink liquid has multiple flow direction turns during the circulation process. The present invention can reduce the problem of crosstalk caused by pressure wave conduction through liquid flow, and at the same time greatly reduces the flow resistance of the ink liquid, which is particularly beneficial to the flow of ink liquid with high viscosity or high solid content (high particle size), and can increase the injection frequency and thus improve the working efficiency of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of inkjet printing equipment, and in particular to a micro-droplet ejection unit and a micro-droplet ejection device. Background Art

[0002] With the development of diversified functional materials for inkjet printing, piezoelectric inkjet print heads have become the mainstream technology for scientific research and industrial inkjet printing due to their wide range of liquid types. The working principle of a piezoelectric nozzle is to selectively apply a driving voltage signal to the piezoelectric element of the nozzle according to the preset printing image. Due to the inverse piezoelectric effect of the piezoelectric material, the piezoelectric element bends and deforms after being stimulated by the electrical signal, squeezing the liquid in the pressure chamber of the nozzle, causing the liquid near the nozzle to be ejected from the nozzle to form the required droplets. With the application of MEMS piezoelectric film in circulating hydraulic electric nozzles, the batch manufacturing characteristics of MEMS processing technology have reduced the manufacturing cost of circulating hydraulic electric nozzles, thereby further promoting the application of piezoelectric nozzles in functional material printing.

[0003] Chinese patent application (application number: CN201680045218.6, hereinafter referred to as "prior art 1") discloses an inkjet print head. Figure 1 and Figure 2 The inkjet printhead mold includes a plurality of droplet units arranged in an array thereon. The droplet unit comprises a nozzle layer, a fluid chamber base, a vibration plate, and an actuator, which are sequentially arranged. The droplet unit includes a fluid chamber and a fluid inlet port connected to the fluid chamber via a fluid supply channel, and also includes a fluid outlet port connected to the fluid chamber via a fluid return channel. The nozzle layer is provided with a nozzle connected to the fluid chamber. When the actuator receives a driving waveform signal and generates stress, causing the vibration plate to deform, the vibration plate squeezes the liquid in the fluid chamber. At this time, the liquid near the nozzle is subjected to an instantaneous thrust and rushes out of the nozzle to form a droplet.

[0004] It will be understood by those skilled in the art that when the vibration plate of a certain droplet unit squeezes the liquid in the fluid chamber to spray droplets, the pressure wave provided by the vibration plate will be transmitted to the circulating liquid pool through the liquid flow, causing adverse effects on the liquid supply stability of the circulating liquid pool, and further interfering with the spraying work of other droplet units. In response to the above problems, the existing common solution is: a narrow channel with a smaller cross-sectional area is provided at both ends of the fluid chamber, and the liquid flow direction in the narrow channel is the same as the liquid flow direction in the fluid chamber, and the conduction of the pressure wave through the liquid flow is eliminated through the narrow channel. For example, in the solution of prior art 1, the liquid flow direction of the fluid inlet port and the fluid supply channel is the same, the fluid supply channel and the fluid chamber are provided with a narrow fluid channel, the liquid flow direction of the fluid outlet port and the fluid return channel is the same, and the fluid return channel and the fluid chamber are provided with another narrow fluid channel. Refer to prior art 1 Figure 1 and Figure 2 Compared with the fluid chamber, the height and width of the fluid channel therein are smaller, that is, it is formed into a narrow channel with a small cross-sectional area.

[0005] Although the above solution can greatly reduce the problem of crosstalk caused by pressure waves transmitted through liquid flow, such a solution will also bring the following problems: the narrow channels connected at both ends of the fluid chamber will cause the flow resistance of high-viscosity or high-solid content (high particle size) ink liquid to increase, resulting in a decrease in the liquid supply flow rate of the nozzle, affecting the injection frequency and reducing work efficiency. Summary of the Invention

[0006] In view of this, the present invention provides a micro-droplet ejection unit and a micro-droplet ejection device to solve the problem of how to reduce the crosstalk caused by the transmission of pressure waves through liquid flow while avoiding increasing the flow resistance of the ink liquid, thereby realizing the ejection of liquids with high viscosity or high solid content (high particle size).

[0007] In order to solve the above problems, one aspect of the present invention is to provide a micro-droplet ejection unit, comprising a nozzle layer, a pressure chamber base layer, a deformable diaphragm, a piezoelectric actuator and an encapsulation protection layer arranged in sequence, wherein the pressure chamber base layer is provided with a pressure chamber, a first liquid inlet channel and a first liquid outlet channel, the pressure chamber extends along a first direction, the first liquid inlet channel extends along a second direction, the first liquid outlet channel extends along a third direction, a first end of the first liquid inlet channel is openly connected to a side surface of the first end of the pressure chamber, a first end of the first liquid outlet channel is openly connected to a side surface of the second end of the pressure chamber, and a nozzle connected to the pressure chamber is provided in the nozzle layer;

[0008] A liquid inlet and a liquid outlet are formed in the encapsulation protection layer, the liquid inlet extends along the fourth direction and is connected to the second end of the first liquid inlet channel, and the liquid outlet extends along the fifth direction and is connected to the second end of the first liquid outlet channel;

[0009] In which, with the XYZ three-dimensional coordinate system as a reference, the first direction, the second direction and the third direction are located in the XY plane, the second direction and the first direction have an angle α1, the third direction and the first direction have an angle β1, the fourth direction and the Z axis have an angle θ1 of 0° to 30°, and the fifth direction and the Z axis have an angle θ2 of 0° to 30°.

[0010] Preferably, the angle α1 is 60° to 120°, and the angle β1 is 60° to 120°.

[0011] Preferably, the angle α1 is 85° to 95°, the angle β1 is 85° to 95°, the angle θ1 is 0° to 5°, and the angle θ2 is 0° to 5°.

[0012] Preferably, the included angle α1 and the included angle β1 have the same angle value, and the included angle θ1 and the included angle θ2 have the same angle value.

[0013] Preferably, the side where the first end of the first liquid inlet channel communicates with the pressure chamber and the side where the first end of the first liquid outlet channel communicates with the pressure chamber are two opposite side surfaces.

[0014] Preferably, the pressure chamber has a width D perpendicular to the first direction, the first liquid inlet channel has a length L1 along the second direction, and the first liquid outlet channel has a length L2 along the third direction, the length L1 is 0.5 to 2 times the width D, and the length L2 is 0.5 to 2 times the width D.

[0015] Preferably, the length L1 and the length L2 have the same length value.

[0016] Preferably, a second liquid inlet channel and a second liquid outlet channel are also provided in the base layer of the pressure chamber, the second liquid inlet channel extends along the sixth direction, the second liquid outlet channel extends along the seventh direction, the sixth direction and the seventh direction are located in the XY plane, the sixth direction and the second direction have an angle α2, and the seventh direction and the third direction have an angle β2; the first end of the second liquid inlet channel is connected to the second end of the first liquid inlet channel, the liquid inlet is connected to the second end of the second liquid inlet channel, the first end of the second liquid outlet channel is connected to the second end of the first liquid outlet channel, and the liquid outlet is connected to the second end of the second liquid outlet channel.

[0017] In order to solve the above problems, another aspect of the present invention is to provide a micro-droplet ejecting device, which includes the micro-droplet ejecting unit as described above.

[0018] Furthermore, the micro-droplet ejection device includes a plurality of the micro-droplet ejection units arranged in an array of M rows × N columns, where M is an integer greater than 1 and N is an integer greater than 1; wherein the first direction in which the length of the pressure chamber in the micro-droplet ejection unit extends is obliquely intersected with the row direction of the array arrangement.

[0019] The micro-droplet ejection unit and micro-droplet ejection device provided by the embodiments of the present invention have a liquid inlet channel located at the liquid inlet end that is open and communicated with the side of the pressure chamber, and a liquid outlet channel located at the liquid outlet end that is also open and communicated with the side of the pressure chamber, and there are no narrow and long channels on the fluid channels at the liquid inlet end and the liquid outlet end of the pressure chamber, thereby greatly reducing the flow resistance of the ink liquid, which is particularly beneficial to the flow of ink liquid with high viscosity or high solid content (high particle size), and can increase the ejection frequency and thus improve the working efficiency of the device; on the other hand, by improving the extension direction of the fluid channels of various parts of the liquid inlet end and the liquid outlet end, the ink liquid has multiple flow direction turns during the circulation process, absorbing the pressure waves that flow with the liquid when ejecting droplets, and avoiding the pressure waves being transmitted to the circulating liquid pool and causing crosstalk to other micro-droplet ejection units. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 1 is a top view of a micro-droplet ejection unit in an embodiment of the present invention;

[0021] Figure 2 It is along Figure 1 Cross-section along the dashed line AA;

[0022] Figure 3 It is along Figure 1 Cross-section along the dashed line BB;

[0023] Figure 4 is a top view of a micro-droplet ejection unit in another embodiment of the present invention;

[0024] Figure 5 Schematic diagram of the structure of the micro-droplet ejection device in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. Examples of these preferred embodiments are illustrated in the accompanying drawings. The embodiments of the present invention shown in and described with reference to the accompanying drawings are merely exemplary, and the present invention is not limited to these embodiments.

[0026] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, the accompanying drawings only show structures and / or processing steps closely related to the solutions according to the present invention, while other details that are not closely related to the present invention are omitted.

[0027] The embodiment of the present invention first provides a micro-droplet ejection unit, referring to Figures 1 to 3 The micro-droplet ejection unit 100 includes a nozzle layer 1, a pressure chamber base layer 2, a deformable diaphragm 3, a piezoelectric actuator 4 and a packaging protection layer 5 which are arranged in sequence.

[0028] In which, a pressure chamber 21, a first liquid inlet channel 22 and a first liquid outlet channel 23 are provided in the pressure chamber base layer 2. The nozzle layer 1 is located relatively below the pressure chamber base layer 2, and a nozzle 11 connected to the pressure chamber 21 is provided in the nozzle layer 1. The deformable diaphragm 3 is located relatively above the pressure chamber base layer 2, and the deformable diaphragm 3, the nozzle layer 1 and the pressure chamber base layer 2 jointly surround and seal the various cavities provided in the pressure chamber base layer 2, such as the pressure chamber 21, the first liquid inlet channel 22 and the first liquid outlet channel 23. The piezoelectric actuator 4 is arranged on the deformable diaphragm 3 and is located above the pressure chamber 21. The packaging protective layer 5 is covered on the piezoelectric actuator 4, and a liquid inlet 51 and a liquid outlet 52 are provided in the packaging protective layer 5.

[0029] The liquid inlet 51 is connected to the pressure chamber 21 via the first liquid inlet channel 22, and the liquid outlet 52 is connected to the pressure chamber 21 via the first liquid outlet channel 23. The liquid inlet 51 is also connected to an external circulating liquid pool via an external positive pressure pump, and the liquid outlet 52 is also connected to the external circulating liquid pool via an external negative pressure pump. Driven by the external positive pressure pump, the ink in the circulating liquid pool enters through the liquid inlet 51, passes through the first liquid inlet channel 22, and enters the pressure chamber 21. Driven by the external negative pressure pump, the ink in the pressure chamber 21 passes through the first liquid outlet channel 23 and returns to the external circulating liquid pool via the liquid outlet 52, forming a continuous liquid circulation flow.

[0030] When the micro-droplet ejection unit 100 is performing the ejection operation, the piezoelectric brake 4 receives the driving waveform signal to generate stress, causing the deformable diaphragm 3 to deform. The deformable diaphragm 3 squeezes the ink liquid in the pressure chamber 21, and the ink liquid near the nozzle 11 is subjected to instantaneous thrust to rush out of the nozzle to form ejected droplets.

[0031] The nozzle layer 1 can be made of a non-deformable and corrosion-resistant material such as silicon, glass, or metal such as nickel or stainless steel, and preferably has a thickness of 10 to 100 μm. The nozzle 11 extending through the nozzle layer 1 preferably has a circular opening, and the opening diameter of the nozzle 11 is preferably 10 to 100 μm. The nozzle shape can be achieved through photolithography combined with etching or electroplating processes, or through processes such as laser drilling.

[0032] As a preferred solution, in this embodiment, the nozzle 11 is arranged at a position corresponding to the exact center of the pressure chamber 21 .

[0033] The pressure chamber base layer 2 can be made of a non-deformable and corrosion-resistant material such as silicon, glass, or metal such as Ni or stainless steel, and preferably has a thickness of 10 μm to 100 μm. Each cavity in the pressure chamber base layer 2, such as the pressure chamber 21, the first liquid inlet channel 22, and the first liquid outlet channel 23, can be formed by photolithography combined with etching or electroplating.

[0034] The deformable partition 3 may be made of a deformable thin film material, and the specific material may be metal, alloy, dielectric material, semiconductor material or polyimide, etc.

[0035] The piezoelectric actuator 4 includes a lower electrode 41, a piezoelectric element 42, and an upper electrode 43, which are sequentially arranged on the deformable diaphragm 3. Specifically, a lower metal film, such as Ti / Pt or Ti / Ir, can be deposited on the deformable diaphragm 3. A piezoelectric film, such as a PZT film, is then deposited on the lower metal film. An upper metal film, such as Pt or Ir, is then deposited. Through photolithography and etching, the piezoelectric actuator 4 is formed, comprising the lower electrode 41, the piezoelectric element 42, and the upper electrode 43. Furthermore, a passivation layer, such as SiO2, SiN, or a combination thereof, is deposited to form a passivation layer 44, which separates the lower electrode 41 from the upper electrode 43 to prevent short circuits during subsequent processing. Through photolithography and etching, the passivation layer 44 opens openings for electrical connection between the lower electrode 41 and the upper electrode 43. Thin film deposition and etching are then performed at the openings to form lower and upper electrode leads 45 and 46, which are electrically connected to the outside world.

[0036] Furthermore, as a preferred solution, the piezoelectric element 42 has a rectangular structure and is arranged along the length direction of the pressure chamber 21 .

[0037] The packaging protection layer 5 is mainly used to separate the piezoelectric actuator 4 from liquids such as ink, and protect the piezoelectric actuator 4 from external contamination or damage by external forces, etc. The packaging protection layer 5 is made of a suitable material such as silicon or glass and is etched to form a desired structure.

[0038] In the embodiment of the present invention, see Figures 1 to 3The pressure chamber 21 extends along a first direction, the first liquid inlet channel 22 extends along a second direction, and the first liquid outlet channel 23 extends along a third direction. The first end of the first liquid inlet channel 22 is open and connected to the side of the first end of the pressure chamber 21, and the first end of the first liquid outlet channel 23 is open and connected to the side of the second end of the pressure chamber 21. It should be noted that the first end of the first liquid inlet channel 22 is open and connected to the side of the pressure chamber 21, that is, the end surface of the first end of the first liquid inlet channel 22 is completely open. This can be understood as the size and shape of the connection interface being the same as the cross-section of the first liquid inlet channel 22. Similarly, the first end of the first liquid outlet channel 23 is open and connected to the side of the pressure chamber 21 in the same way as above. Furthermore, the liquid inlet 51 extends along a fourth direction and connects to the second end of the first liquid inlet channel 22, and the liquid outlet 52 extends along a fifth direction and connects to the second end of the first liquid outlet channel 23.

[0039] Among them, the first liquid inlet channel 22, the first liquid outlet channel 23 and the pressure chamber 21, the liquid inlet 51 and the first liquid inlet channel 22, and the liquid outlet 52 and the first liquid outlet channel 23 are extended and connected to each other in directions at a certain angle, so that the ink liquid has multiple flow direction turns during the circulation process.

[0040] Specifically, with the XYZ three-dimensional coordinate system as a reference, the first, second, and third directions described above are located within the XY plane. The second direction is defined by an angle α1 with the first direction, the third direction is defined by an angle β1 with the first direction, the fourth direction is defined by an angle θ1 with the Z axis of 0° to 30°, and the fifth direction is defined by an angle θ2 with the Z axis of 0° to 30°. Furthermore, the angle α1 is preferably 60° to 120°. The angle β1 is preferably 60° to 120°.

[0041] As a preferred solution, the included angle α1 and the included angle β1 have the same angle value, and the included angle θ1 and the included angle θ2 have the same angle value.

[0042] The angle α1 is further preferably 85° to 95°, the angle β1 is further preferably 85° to 95°, the angle θ1 is further preferably 0° to 5°, and the angle θ2 is further preferably 0° to 5°. That is, the second direction and the first direction are perpendicular or nearly perpendicular to each other, the third direction and the first direction are perpendicular or nearly perpendicular to each other, and the fourth direction and the fifth direction are respectively perpendicular to the XY plane or nearly perpendicular to the XY plane.

[0043] The most preferred solution is Figure 1 As shown, the second direction and the third direction are perpendicular to the first direction, and the fourth direction and the fifth direction are perpendicular to the XY plane, that is, in the XYZ three-dimensional coordinate system, the first direction is in the X-axis direction, the second direction and the third direction are in the Y-axis direction, and the fourth direction and the fifth direction are in the Z-axis direction. That is, the first liquid inlet channel 22 and the first liquid outlet channel 23 are connected to the pressure chamber 21 perpendicularly, the liquid inlet 51 and the first liquid inlet channel 22 are connected perpendicularly, and the liquid outlet 52 and the first liquid outlet channel 23 are connected perpendicularly. The ink liquid has multiple 90° turns in its flow direction during the circulation process. It should be noted that Figures 1 to 3 In the symbol Indicates that the ink liquid flows in the direction of the arrow in the viewing plane, the symbol "⊙" indicates that the ink liquid flows inward along the direction perpendicular to the viewing plane, and the symbol The ink liquid is shown flowing outward in a direction perpendicular to the viewing plane.

[0044] In the embodiment of the present invention, Figure 1 As shown, the side where the first end of the first liquid inlet channel 22 communicates with the pressure chamber 21 and the side where the first end of the first liquid outlet channel 23 communicates with the pressure chamber 21 are two opposite side surfaces.

[0045] Further, see Figure 2 The pressure chamber has a width D perpendicular to the first direction, the first liquid inlet channel has a length L1 along the second direction, and the first liquid outlet channel has a length L2 along the third direction (not shown in the drawings). The length L1 is preferably 0.5 to 2 times the width D, and the length L2 is preferably 0.5 to 2 times the width D. Furthermore, the lengths L1 and L2 are preferably set to have the same length value.

[0046] As described in the above embodiment, the micro-droplet ejection unit has an inlet channel at the inlet end that is open and communicated with the side of the pressure chamber, and a liquid outlet channel at the outlet end that is open and communicated with the side of the pressure chamber, and there are no narrow channels on the fluid channels at the inlet end and the outlet end of the pressure chamber, thereby greatly reducing the flow resistance of the ink liquid, which is particularly beneficial to the flow of ink liquid with high viscosity or high solid content (high particle size), and can increase the ejection frequency and thus improve the working efficiency of the device; on the other hand, by improving the extension direction of the fluid channels of various parts of the inlet end and the outlet end, the ink liquid has multiple flow direction turns during the circulation process, absorbing the pressure waves that flow with the liquid when ejecting droplets, and avoiding the pressure waves from being transmitted to the circulating liquid pool and causing crosstalk to other micro-droplet ejection units.

[0047] In some other embodiments of the micro-droplet ejection unit 100, in order to further eliminate the conduction of the pressure wave along with the flow of the liquid, refer to Figure 4 The pressure chamber base layer may also include a second liquid inlet channel 24 and a second liquid outlet channel 25. The second liquid inlet channel 24 extends along a sixth direction, and the second liquid outlet channel 25 extends along a seventh direction. The sixth and seventh directions lie within the XY plane. The sixth and second directions form an angle α2, and the seventh and third directions form an angle β2. The first end of the second liquid inlet channel 24 is connected to the second end of the first liquid inlet channel 22. The liquid inlet 51 is connected to the second end of the second liquid inlet channel 24. The first end of the second liquid outlet channel 25 is connected to the second end of the first liquid outlet channel 23. The liquid outlet 52 is connected to the second end of the second liquid outlet channel 25. Specifically, the second liquid inlet channel 24 is provided between the liquid inlet 51 and the first liquid inlet channel 22, and the second liquid outlet channel 25 is provided between the liquid outlet 52 and the first liquid outlet channel 23. This increases the number of turns in the ink's flow direction during circulation, further eliminating the transmission of pressure waves along with the liquid flow.

[0048] Among them, the angle α2 can be set to 60°~120°, further preferably 85°~95°, and most preferably 90°, that is, the second liquid inlet channel 24 and the first liquid inlet channel 22 are connected to each other perpendicularly; the angle β2 can be set to 60°~120°, further preferably 85°~95°, and most preferably 90°, that is, the second liquid outlet channel 25 and the first liquid outlet channel 23 are connected to each other perpendicularly.

[0049] The second liquid inlet channel 24 has a length L3 along the sixth direction, and the second liquid outlet channel 25 has a length L4 along the seventh direction. The length L3 is preferably 0.5 to 2 times the length L1, and the length L4 is preferably 0.5 to 2 times the length L2.

[0050] Based on the micro-droplet ejection unit 100 provided in the above embodiment, the present invention further provides a micro-droplet ejection device, see Figure 5 The micro-droplet ejection device includes a plurality of micro-droplet ejection units 100 arranged in an array of M rows by N columns, where M is an integer greater than or equal to 1, and N is an integer greater than or equal to 1. The first direction in which the length of the pressure chambers 21 in the micro-droplet ejection units 100 extends is obliquely intersecting with the row direction of the array arrangement. All micro-droplet ejection units 100 in the same row are inclined in the same direction, and the inclination directions of the micro-droplet ejection units 100 in different rows can be the same or different.

[0051] Specifically, if Figure 5 , the micro-droplet ejection device of this embodiment includes two rows of the micro-droplet ejection units 100, each row includes a plurality of micro-droplet ejection units 100 arranged in parallel and tilted, and the array of micro-droplet ejection units 100 is tilted at a certain angle, which can increase the number of arrangements.

[0052] In the example of the array arrangement from left to right in the diagram, all the micro-droplet ejecting units 100 in the first row are tilted to the right, while all the micro-droplet ejecting units 100 in the second row are tilted to the left. The nozzles of the two adjacent rows of micro-droplet ejecting units 100 are staggered to increase nozzle resolution.

[0053] Furthermore, the lower electrode leads 45 of the two adjacent rows of micro-droplet ejection units 100 are placed adjacent to each other and connected to the common ground line 200, and the upper electrode leads 46 of each micro-droplet ejection unit 100 are independently provided with a driving electrode 300, which is connected to the external driving circuit through the driving electrode 300 to independently drive each ejection unit to work.

[0054] It should be noted that the above embodiments are merely illustrative of the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent variations or modifications made in accordance with the spirit and substance of the present invention are intended to be encompassed within the scope of protection of the present invention.

Claims

1. A micro-droplet ejection unit, comprising a nozzle layer, a pressure chamber base layer, a deformable diaphragm, a piezoelectric actuator and an encapsulation protection layer arranged in sequence, characterized in that: The pressure chamber base layer is provided with a pressure chamber, a first liquid inlet channel, and a first liquid outlet channel. The pressure chamber extends along a first direction, the first liquid inlet channel extends along a second direction, and the first liquid outlet channel extends along a third direction. A first end of the first liquid inlet channel is openly connected to a side surface of the first end of the pressure chamber, and a first end of the first liquid outlet channel is openly connected to a side surface of the second end of the pressure chamber. A nozzle connected to the pressure chamber is provided in the nozzle layer. A liquid inlet and a liquid outlet are formed in the encapsulation protection layer, the liquid inlet extends along the fourth direction and is connected to the second end of the first liquid inlet channel, and the liquid outlet extends along the fifth direction and is connected to the second end of the first liquid outlet channel; Wherein, with the XYZ three-dimensional coordinate system as a reference, the first direction, the second direction, and the third direction are located in the XY plane, an angle α1 is formed between the second direction and the first direction, an angle β1 is formed between the third direction and the first direction, an angle θ1 between the fourth direction and the Z axis is 0° to 30°, and an angle θ2 between the fifth direction and the Z axis is 0° to 30°; A second liquid inlet channel and a second liquid outlet channel are also provided in the base layer of the pressure chamber. The second liquid inlet channel extends along the sixth direction, and the second liquid outlet channel extends along the seventh direction. The sixth direction and the seventh direction are located in the XY plane. There is an angle α2 between the sixth direction and the second direction, and there is an angle β2 between the seventh direction and the third direction. The first end of the second liquid inlet channel is connected to the second end of the first liquid inlet channel, the liquid inlet is connected to the second end of the second liquid inlet channel, the first end of the second liquid outlet channel is connected to the second end of the first liquid outlet channel, and the liquid outlet is connected to the second end of the second liquid outlet channel.

2. The micro-droplet ejection unit according to claim 1, characterized in that: The included angle α1 is 60° to 120°, and the included angle β1 is 60° to 120°.

3. The micro-droplet ejection unit according to claim 2, characterized in that: The included angle α1 is 85° to 95°, the included angle β1 is 85° to 95°, the included angle θ1 is 0° to 5°, and the included angle θ2 is 0° to 5°.

4. The micro-droplet ejection unit according to claim 1, characterized in that: The included angle α1 and the included angle β1 have the same angle value, and the included angle θ1 and the included angle θ2 have the same angle value.

5. The micro-droplet ejection unit according to claim 4, characterized in that: The side surface where the first end of the first liquid inlet channel communicates with the pressure chamber and the side surface where the first end of the first liquid outlet channel communicates with the pressure chamber are two opposite side surfaces.

6. The micro-droplet ejection unit according to claim 1, characterized in that: The pressure chamber has a width D perpendicular to the first direction, the first liquid inlet channel has a length L1 along the second direction, and the first liquid outlet channel has a length L2 along the third direction. The length L1 is 0.5 to 2 times the width D, and the length L2 is 0.5 to 2 times the width D.

7. The micro-droplet ejection unit according to claim 6, characterized in that: The length L1 and the length L2 have the same length value.

8. A micro-droplet ejection device, characterized in that: The invention comprises the micro-droplet ejecting unit according to any one of claims 1 to 7.

9. The micro-droplet ejection device according to claim 8, characterized in that: The micro-droplet ejection device comprises a plurality of micro-droplet ejection units arranged in an array of M rows × N columns, where M is an integer greater than 1 and N is an integer greater than 1; Wherein, the first direction in which the length of the pressure chamber in the micro-droplet ejection unit extends is obliquely intersected with the row direction of the array arrangement.

Images