A method and apparatus for transverse electrojet printing under electric field confinement

Abstract

This invention relates to an electric field-constrained lateral electrojet printing method and apparatus. The printing method includes the following steps: ink is ejected from a nozzle into a lateral jet under the action of a driving electric field; a constraining electric field is set, the electric field force acting on the ink in the lateral jet is sufficient to counteract the gravity of the ink, allowing the jet to be precisely deposited horizontally at a predetermined position; finally, a three-dimensional motion platform is used to achieve the printing of micro / nano structures on the side surface. This method has advantages such as wide material applicability, high printing resolution, and high control precision, enabling rapid, high-quality, and low-cost electrojet printing of micro / nano structures on the side surface.

Description

Technical Field

[0001] This invention belongs to the fields of advanced manufacturing technology and micro-nano manufacturing technology, and specifically relates to an electric field-constrained lateral electrojet printing method. Background Technology

[0002] Electro-jet printing (E-Jet) utilizes an electric field to stretch liquid ink into jets or droplets with diameters in the micrometer or even nanometer range and deposit them onto a target surface. The process is as follows: A high-voltage driving electric field is applied between the nozzle and the substrate. The ink initially forms a meniscus at the nozzle exit under the combined influence of feed pressure, gravity, and surface tension. As the driving voltage increases, the meniscus stretches into a cone shape under the driving electric field, called a Taylor cone, and eventually overcomes surface tension, ejecting a jet of micrometer or even nanometer scale. Combined with a three-dimensional motion platform, this achieves the printing of micro / nano-scale structures. Compared to traditional micro / nano manufacturing methods such as photolithography and laser sintering, E-jet printing offers advantages such as simple and flexible processes, wide material applicability, and lower requirements for target surface conditions. Therefore, E-jet printing is widely used in various micro / nano fabrication fields, such as microfluidic chips and micro / nano-scale electrode manufacturing.

[0003] Due to the influence of gravity, all current electro-jet printing systems are vertical, which cannot meet the requirements for printing micro- and nano-structures on the side surfaces of objects, such as the fabrication of side electrodes for shear wave elements in nonlinear phased arrays. However, if the electro-jet printing system is placed horizontally, the transverse jet and the printed structure will deviate from their intended positions under the influence of gravity, severely affecting the forming quality of transverse electro-jet printing. Summary of the Invention

[0004] To overcome the shortcomings of the aforementioned electrojets for printing micro / nano structures on side surfaces, this invention provides a transverse electrojet printing method with electric field constraint. During transverse electrojet printing, ink is ejected from the nozzle as a transverse jet under the influence of a driving electric field. The magnitude and direction of the constraint electric field are adjusted by changing the field strength and polarity of the constraint electric field according to the ink density and the size of the transverse jet. This controls the degree of constraint on the transverse jet, thus counteracting gravity and allowing the transverse jet to be precisely deposited at a predetermined position. Finally, a three-dimensional motion platform is used to achieve the printing of micro / nano structures on the side surface. This method has advantages such as wide material applicability, high printing resolution, and high control precision, enabling rapid, high-quality, and low-cost electrojet printing of micro / nano structures on side surfaces.

[0005] The technical solution adopted by the present invention to solve the aforementioned technical problem is as follows:

[0006] In a first aspect, the present invention provides an electric field-constrained transverse electrojet printing method, the printing method comprising the following: ink is ejected from a nozzle into a transverse jet under the action of a driving electric field force;

[0007] A constraint electric field is set up so that the electric field force of the constraint electric field acting on the ink of the transverse jet can counteract the gravity of the ink, so that the jet is accurately deposited at a predetermined position in a horizontal direction.

[0008] Finally, a three-dimensional motion platform was used to print the micro-nano structures on the side surface.

[0009] Preferably, laser sensors are installed at the same height at the starting and ending points of the transverse ink jet, and the laser sensors detect the height difference between the starting and ending points of the transverse jet in real time.

[0010] The constrained electric field control program is as follows: set the voltage adjustment step size k and the height difference threshold h0 of the constrained electric field, and obtain the height difference between the starting point and the ending point of the transverse jet in real time.

[0011] Given the initial field strength of the constraint electric field, obtain the height difference, and adjust the field strength of the constraint electric field in real time according to the set voltage adjustment step size k based on the height difference until the height difference is controlled within the set height difference threshold h0. Record the constraint electric field strength and polarity at this time.

[0012] Side surface micro / nano structures are printed under the electric field strength and polarity constraints required for the current ink lateral jet printing, as determined by the constrained electric field control program.

[0013] More preferably, the height difference threshold h0 is no greater than 100 μm, and when the height difference is in the range of (-h0, h0), the output constraint electric field strength and polarity are determined; the voltage adjustment step size k is adjusted in the range of 10-100V.

[0014] Preferably, the constraint electric field is first applied gradually according to the step size k0, and the height difference is calculated in real time; it is determined whether the height difference is greater than the first height difference threshold h1. If it is, the voltage adjustment step size is set to the first voltage adjustment step size k1; if it is not greater than the first height difference threshold h1, it is determined whether the height difference is greater than the second height difference threshold h2. If it is, the voltage adjustment step size is set to the second voltage adjustment step size k2; if it is not greater than the second height difference threshold h2, it is determined whether the height difference is greater than the third height difference threshold h3. If it is, the voltage adjustment step size is set to the third voltage adjustment step size k3, until the jet height difference reaches the range of (-h0, h0);

[0015] k0 is 500V, and k1, k2, and k3 are taken in the range of 10-100V; h is the height difference between the start and end points of the jet when no constraint electric field is applied; h1 is h / 2, h2 is h / 5, and h3 is h / 10; the height difference is the height of the start point minus the height of the end point. When the height difference is positive, the constraint electric field strength is increased by a step size, and when the height difference is negative, the constraint electric field strength is decreased by a step size.

[0016] The voltage adjustment step size described in this invention can also be selected according to the conductivity of the ink; for inks with poor conductivity, the voltage adjustment step size should be larger.

[0017] Secondly, the present invention provides an electric field-constrained transverse electrojet printing device, comprising an XYZ three-dimensional motion platform and a heating module. The XYZ three-dimensional motion platform includes an X motion axis 1, a Y motion axis 2, a Z motion axis 3, and a controller 4. The printing device further includes a transverse electrojet printing module and a constraint electric field generating module. The heating module includes a temperature controller 18 and a heating plate 22.

[0018] The horizontal electro-jet printing module includes a Luer needle adapter 8, a right-angle nozzle 9, a needle clamp 10, a hose 11, a syringe 13, a micro-feed pump 14, and a high-voltage drive electric field generating power supply 15. The Luer needle adapter 8 and the right-angle nozzle 9 are connected by threads. The high-voltage end of the high-voltage drive electric field generating power supply 15 is connected to the right-angle nozzle 9, and the ground end is connected to the target object 5, so that a potential difference is generated between the right-angle nozzle 9 and the target object 5. The syringe 13 is fixed on the micro-feed pump 14, and the syringe is filled with ink 12. The syringe is connected to the Luer needle adapter 8 through the hose 11. The vertical section of the right-angle nozzle 9 is connected to the Luer needle adapter 8, and the horizontal section of the right-angle nozzle faces the target object. The end of the horizontal section is the outlet of the right-angle nozzle.

[0019] The confined electric field generating module includes a high-voltage confined electric field generating power supply 17, a near-end laser generator 20, a far-end laser generator 21, an electrode plate 23, a near-end laser receiver 24, a far-end laser receiver 25, and an insulating pad 26; the high-voltage end of the high-voltage confined electric field generating power supply 17 is connected to the electrode plate 23, and the ground end is connected to the target object 5, so that the electrode plate 23 and the right-angle nozzle 9 have electric fields of the same polarity;

[0020] The near-end laser generator 20 and near-end laser receiver 24 are placed at the starting point of the jet, and the far-end laser generator 21 and far-end laser receiver 25 are placed at the ending point of the jet.

[0021] The high-voltage confinement electric field generating power supply 17, near-end laser generator 20, far-end laser generator 21, near-end laser receiver 24, and far-end laser receiver 25 are all electrically connected to the confinement control unit and are used to adjust the confinement electric field strength according to the laser detection results.

[0022] An L-shaped connecting plate 27 is fixedly installed on the Z-axis. The vertical surface of the L-shaped connecting plate is fixed to the Z-axis, and the horizontal surface supports the electrode plate, insulating pad, heating plate and target object 5.

[0023] A heating plate 22 and an insulating pad 26 are arranged sequentially from bottom to top on the horizontal surface of the L-shaped connecting plate 27. A groove for placing an electrode plate 23 is provided on the side of the insulating pad away from the Z-axis. The electrode plate is placed in the groove of the insulating pad, and the target object is fixed on the side of the insulating pad without a groove.

[0024] Furthermore, the distance from the horizontal end of the right-angle nozzle to the target object is on the order of millimeters; the printing device is also equipped with a CCD high-speed camera for real-time monitoring of the jet morphology; the constraint control unit is a PC, computer, or MCU microcontroller, etc.

[0025] The X-axis and Y-axis use SURUGASEIKIK XL06050 series motion axes with a travel range of 0-50mm, a speed of 0-30mm / s, a resolution of 0.2μm, and a repeatability of 0.5μm; the Z-axis uses SURUGASEIKIK ZL06050 series motion axes with a travel range of 0-50mm, a speed of 0-30mm / s, a resolution of 0.2μm, and a repeatability of 0.5μm.

[0026] The right-angle nozzle 9 has an inner diameter of 80-300μm and is made of stainless steel; the ink 12 is ink used for electro-jet printing; the micro-feed pump 14 uses a Harvard Pump 11 Elite series feed pump with a feed rate of 3.66pl / min-3.82ml / min, a stability accuracy of 0.35%, and a reproduction accuracy of 0.05%; the high-voltage drive electric field generator 15 uses a Dongwen high-voltage DW-P303 series high-voltage power supply with an output voltage range of 0-30kV and a resolution of 1V.

[0027] The high-voltage confinement electric field generating power supply 17 adopts the Dongwen high-voltage DW-P303 series high-voltage power supply, with an output voltage range of 0-30kV and a resolution of 1V; the electrode plate 23 has dimensions of 80mm in length, 40mm in width, and 1mm in thickness, and is made of stainless steel, and is connected to the insulating pad 26 by adhesive; the insulating pad 26 has dimensions of 80mm in length, 80mm in width, and 2mm in thickness, and has a groove of 80mm in length, 40mm in width, and 1mm in depth milled on its upper surface for placing the electrode plate, and is made of alumina ceramic;

[0028] The heating plate 22 is 80mm long, 80mm wide, and 2mm thick, and is made of brass. It has an embedded resistance wire and a temperature sensor, and is connected to the temperature controller 18. The temperature controller 18 has a temperature control range of 30-80℃ and a resolution of 1℃.

[0029] Thirdly, the present invention provides an electric field-constrained transverse electrojet printing method, wherein the printing method employs the aforementioned electric field-constrained transverse electrojet printing device, and the printing method steps are as follows:

[0030] Step 1: Lateral jet formation

[0031] First, the target object 5 is placed on the insulating pad 26. The ink 12 is drawn out using the syringe 13 and fixed on the micro-feed pump 14. The flow rate is precisely controlled using the micro-feed pump 14. The ink 12 in the syringe 13 is delivered to the right-angle nozzle 9 through the tubing 11 and the Luer needle adapter 8. The electric field strength between the right-angle nozzle 9 and the target object 5 is controlled using the high-voltage driving electric field generator 15. Under the combined action of the driving electric field force, the feed pressure, and the surface tension, the ink 12 forms a transverse jet 7.

[0032] Step 2: Constraining the electric field

[0033] In the absence of a constrained electric field, the transverse jet 7 is deflected downwards by gravity, deviating from the predetermined position. Utilizing the jet's blocking effect on the laser, the near-end laser generator 20 and near-end laser receiver 24 detect the height of the jet's starting point, while the far-end laser generator 21 and far-end laser receiver 25 detect the height of the jet's ending point. The results are input into the constrained control unit. Based on the height difference between the starting and ending points of the transverse jet, the constrained control unit automatically sends a signal to the high-voltage constrained electric field generator 17. The high-voltage constrained electric field generator 17 applies a high-voltage electric field with the same polarity as the ink 12 to the electrode plate 23. According to the principle of like poles repulsion, the transverse jet 7 is deflected upwards by the repulsive force of the constrained electric field, thus counteracting gravity. As the constrained electric field strength increases, the repulsive force on the transverse jet 7 increases, and the degree of upward deflection increases; as the constrained electric field strength decreases, the repulsive force on the transverse jet 7 decreases, and the degree of upward deflection decreases. The constrained electric field strength is automatically adjusted based on the height difference between the starting and ending points of the transverse jet 7, ensuring that the transverse jet 7 is precisely deposited at the predetermined position. A CCD high-speed camera 19 monitors the jet morphology in real time.

[0034] Step 3: Printing micro / nano structures

[0035] Adjust the magnitude of the constraint electric field so that the starting and ending points of the transverse jet 7 are at the same height, at which point the constraint electric field force completely cancels out the influence of gravity; use controller 4 to control the X-axis 1, Y-axis 2, and Z-axis 3 to move according to a predetermined program; use temperature controller 18 to control the temperature of heating 22 to heat the target object 5 and accelerate the solidification of the transverse jet 7; finally, the printing of the micro-nano structure 6 is completed.

[0036] The linewidth of the micro / nano structure 6 is 200nm-300μm, and the printing accuracy is controlled within 100μm.

[0037] Compared with the prior art, the beneficial effects of the present invention are:

[0038] The present invention provides a transverse electrojet printing method under electric field constraint, which creatively achieves transverse printing by utilizing the constrained electric field to counteract gravity.

[0039] The device of this invention uses right-angle nozzles to form a transverse jet. A laser sensor detects the height difference between the starting and ending points of the transverse jet. The device automatically adjusts the magnitude of the constraint electric field based on the height difference to counteract the gravitational influence of the transverse jet. Combined with a three-dimensional motion platform, it realizes the electro-jet printing of micro-nano structures on the side surface.

[0040] The method of this invention has the advantages of wide material applicability, high printing resolution, and high control precision. It can realize the electro-jet printing of side surface micro-nano structures quickly, with high quality and low cost, filling the gap in side surface micro-nano structure manufacturing methods.

[0041] In this invention, the lateral jet length is at the millimeter level, enabling precise control and printing at the microscopic level on the target object.

[0042] The method of this invention can precisely control the magnitude of the confinement electric field to just counteract gravity. A heating module heats the target object. After the lateral jet is deposited on the side of the target object, the solvent evaporates rapidly. At the same time, the printing surface of the target object is brought as close as possible to the confinement electrode plate, so that the confinement electric field can still play a certain role in the deposited structure. However, the target object cannot come into contact with the electrode plate to prevent short circuit. The heating module and the electrode plate work together to reduce the phenomenon of ink flowing downward due to gravity when it reaches the side of the target object, further improving the printing accuracy. Attached Figure Description

[0043] Figure 1 A simplified diagram of an electric field-constrained transverse electrojet printing device.

[0044] Figure 2 Schematic diagram of electric field-constrained transverse electric jet printing.

[0045] Figure 3 Simplified diagram of the relative position of the laser sensor.

[0046] Figure 4 Schematic diagram of the transverse jet pattern in an unconstrained electric field.

[0047] Figure 5 A schematic diagram of the transverse jet pattern under a constrained electric field.

[0048] In the diagram: 1. X-axis motion, 2. Y-axis motion, 3. Z-axis motion, 4. Controller, 5. Target object, 6. Micro / nano structure, 7. Lateral jet, 8. Luer needle adapter, 9. Right-angle nozzle, 10. Needle clamp, 11. Tube, 12. Ink, 13. Syringe, 14. Micro-feed pump, 15. High-voltage drive electric field generator, 16. Computer, 17. High-voltage confinement electric field generator, 18. Temperature controller, 19. CCD high-speed camera, 20. Near-end laser generator, 21. Far-end laser generator, 22. Heating plate, 23. Electrode plate, 24. Near-end laser receiver, 25. Far-end laser receiver, 26. Insulating pad, 27. L-shaped connecting plate. Detailed Implementation

[0049] The present invention will be further explained below with reference to the embodiments and accompanying drawings, but this is not intended to limit the scope of protection of this application.

[0050] The present invention relates to an electric field-constrained transverse electrojet printing method. Ink is ejected from a nozzle into a transverse jet under the action of a driving electric field. The magnitude and direction of the constraining electric field force are adjusted by changing the field strength and polarity of the constraining electric field according to the ink density and the size of the transverse jet. This controls and adjusts the degree of constraint on the transverse jet, achieving precise control of the transverse jet deflection, thereby counteracting gravity and allowing the transverse jet to be accurately deposited at a predetermined position. Finally, the method is combined with a three-dimensional motion platform to achieve the printing of micro-nano structures on the side surface.

[0051] The electric field-constrained transverse electrojet printing device of the present invention includes an XYZ three-dimensional motion platform, a transverse electrojet printing module, a constraint electric field generating module, and a heating module; the XYZ three-dimensional motion platform includes an X motion axis 1, a Y motion axis 2, a Z motion axis 3, a controller 4, and an L-shaped connecting plate 27; the L-shaped connecting plate is fixed on the Z motion axis and is used to support the constraint electric field generating module, the heating module, and the target object 5;

[0052] The lateral electrojet printing module includes a Luer needle adapter 8, a right-angle nozzle 9, a needle clamp 10, a hose 11, ink 12, a syringe 13, a micro-feed pump 14, and a high-voltage drive electric field generating power supply 15. The Luer needle adapter 8 and the right-angle nozzle 9 are connected by threads. The high-voltage end of the high-voltage drive electric field generating power supply 15 is connected to the right-angle nozzle 9, and the ground end is connected to the target object 5, so that a potential difference is generated between the right-angle nozzle 9 and the target object 5. The syringe 13 is fixed on the micro-feed pump 14, contains ink 12, and is connected to the Luer needle adapter 8 through the hose 11.

[0053] The confinement electric field generating module includes a computer 16, a high-voltage confinement electric field generating power supply 17, a CCD high-speed camera 19, a near-end laser generator 20, a far-end laser generator 21, an electrode plate 23, a near-end laser receiver 24, a far-end laser receiver 25, and an insulating pad 26. The high-voltage end of the high-voltage confinement electric field generating power supply 17 is connected to the electrode plate 23, and the ground end is connected to the target object 5, so that the electrode plate 23 and the right-angle nozzle 9 have electric fields of the same polarity. The near-end laser generator 20 and the near-end laser receiver 24 are placed at the starting point of the transverse jet, and the far-end laser generator 21 and the far-end laser receiver 25 are placed at the ending point of the transverse jet. The computer 16 is equipped with a confinement electric field control program, which is used to adjust the field strength of the confinement electric field according to the laser detection results. An L-shaped connecting plate 27 is fixedly installed on the Z-axis. The vertical surface of the L-shaped connecting plate is fixed to the Z-axis, and the horizontal surface supports the electrode plate, the insulating pad, the heating plate, and the target object 5.

[0054] A heating plate 22 and an insulating pad 26 are arranged sequentially from bottom to top on the horizontal surface of the L-shaped connecting plate 27. A groove for placing an electrode plate 23 is provided on the side of the insulating pad away from the Z-axis. The electrode plate is placed in the groove of the insulating pad, and the target object is fixed on the side of the insulating pad without a groove.

[0055] In this embodiment, the near-end laser generator 20 and near-end laser receiver 24 are installed at the same height and horizontal position as the far-end laser generator 21 and far-end laser receiver 25. The far-end laser receiver and far-end laser generator are close to the side of the target object to be printed, but do not contact the target object.

[0056] This invention can also be used to observe the morphology of the transverse jet using a high-speed camera and manually adjust the confinement electric field in real time.

[0057] Example 1

[0058] This embodiment discloses an electric field-constrained transverse electrojet printing method, employing an electric field-constrained transverse electrojet printing device, including an XYZ three-dimensional motion platform, a transverse electrojet printing module, a constraint electric field generation module, and a heating module. The X-axis 1 and Y-axis 2 utilize SURUGASEIKI KXL06050 series motion axes, with a stroke of 0-50 mm, a speed of 0-30 mm / s, a resolution of 0.2 μm, and a repeatability of 0.5 μm. The Z-axis 3 utilizes a SURUGASEIKI KZL06050 series motion axis, with a stroke of 0-50 mm, a speed of 0-30 mm / s, a resolution of 0.2 μm, and a repeatability of 0.5 μm. This series of motion axes enables smooth, high-precision, and large-stroke motion.

[0059] The right-angle nozzle 9 has an inner diameter of 80-300μm and is made of stainless steel. It is connected to the Luer needle adapter 8 via threads. The flexible tube 11 has an inner diameter of 2mm and is made of Teflon. This type of flexible tube is heat-resistant, insulating, has a hydrophobic inner wall, and is not easily deformed. Both ends of the flexible tube 11 are connected to the syringe 13 and the Luer needle adapter 8, respectively, using an overfit connection. The syringe 13 has a capacity of 1ml, a barrel length of 7.8cm, and an inner diameter of 0.6cm, and contains ink 12. The ink 12 can be any ink suitable for... The ink used in traditional electrojet printing has no special requirements; the micro-feed pump 14 uses a Harvard Pump 11 Elite series feed pump with a feed rate of 3.66 pl / min-3.82 ml / min, a stability accuracy of 0.35%, and a reproduction accuracy of 0.05%; the high-voltage drive electric field generator 15 uses a Dongwen high-voltage DW-P303 series high-voltage power supply with an output voltage range of 0-30kV and a resolution of 1V. The high-voltage end is connected to the right-angle needle 9, and the grounding end is connected to the target object 5.

[0060] The high-voltage confinement electric field generating power supply 17 adopts the Dongwen high-voltage DW-P303 series high-voltage power supply, with an output voltage range of 0-30kV and a resolution of 1V. The high-voltage end is connected to the electrode plate 8, and the grounding end is connected to the target object 5. The electrode plate 23 is 80mm long, 40mm wide, and 1mm thick, and is made of stainless steel. It is connected to the insulating pad 26 by adhesive. The insulating pad 26 is 80mm long, 80mm wide, and 2mm thick. A groove of 80mm long, 40mm wide, and 1mm deep is milled on its upper surface to place the electrode plate 25. The material is alumina ceramic, which has good insulation and thermal conductivity.

[0061] The heating plate 22 is 80mm long, 80mm wide, and 2mm thick, and is made of brass. It has an embedded resistance wire and a temperature sensor, and is connected to the temperature controller 18. The temperature controller 18 has a temperature control range of 30-80℃ and a resolution of 1℃.

[0062] A transverse electric jet printing method under electric field constraint, the principle of which is as follows:

[0063] As attached Figure 2 As shown, a high-voltage driving electric field generator 15 inputs high voltage to the right-angle nozzle 9. At this time, the ink 12 carries a positive charge, and the surface of the target object 5 is induced with a negative charge. Under the attraction of the driving electric field, a transverse jet 7 is ejected. If there is no constraining electric field, the transverse jet 7 will be deflected downwards under the influence of gravity, as shown in the attached diagram. Figure 4As shown, the degree of deflection varies depending on the mass of ink 12 and the size of the transverse jet 7. When a high-voltage confined electric field generator 17 inputs high voltage to the electrode plate 23, the electrode plate 23 becomes positively charged, providing a repulsive force to the transverse jet 7, counteracting the effect of gravity and causing the transverse jet to be ejected laterally, as shown in the attached diagram. Figure 5 As shown in the attached diagram; utilizing the blocking effect of the transverse jet on the laser, a near-end laser generator 20 and a near-end laser receiver 24 are used to detect the starting height of the transverse jet, and a far-end laser generator 21 and a far-end laser receiver 25 are used to detect the ending height of the transverse jet. Figure 3 As shown, the results are input into the control software in the computer 16. Based on the height difference between the starting point and the ending point of the transverse jet 7, the computer 16 automatically sends a signal to the high-voltage confinement electric field power source 17 and automatically adjusts the output voltage of the high-voltage confinement electric field power source 17 so that the repulsive force can accurately counteract the gravity, thereby achieving precise printing of the transverse electric jet.

[0064] A method for transverse electrojet printing under electric field constraint, comprising the following steps:

[0065] Step 1: Lateral jet formation

[0066] The target object 5 is placed on the insulating pad 26, without contacting the electrode plate 23 to prevent short circuit. 0.1-1 ml of ink 12 is drawn using the syringe 13 and fixed on the micro-feed pump 14. The micro-feed pump 14 is used to apply a stable feed rate of 0.1-10 μl / min. The ink 12 in the syringe 13 is delivered to the right-angle nozzle 9 through the tubing 11 and the Luer needle adapter 8. The inner diameter of the right-angle nozzle 9 is 80-300 μm. A high-voltage driving electric field generator 15 is used to input a voltage of 100-5000V to the right-angle nozzle 9. Under the combined action of the driving electric field force, feed pressure, and surface tension, the ink 12 forms a transverse jet 7.

[0067] Step 2: Constraining the electric field

[0068] When the confinement electric field strength is 0V, the transverse jet 7 is deflected downwards by gravity, deviating from the predetermined position. The height of the transverse jet's starting point is detected by the near-end laser generator 20 and the near-end laser receiver 24, and the height of the transverse jet's ending point is detected by the far-end laser generator 21 and the far-end laser receiver 25, and the data is input into the control software in the computer 16. The control software sends a signal to the high-voltage confinement electric field power source 17 based on the height difference, inputs a voltage of 0-10000V to the electrode plate 23, and automatically adjusts the confinement electric field strength in real time according to the height difference. It uses electrostatic repulsion to precisely counteract gravity, causing the transverse jet 7 to be ejected horizontally. A CCD high-speed camera monitors the morphology of the transverse jet, ensuring that the transverse jet 7 is precisely deposited at the predetermined position.

[0069] Step 3: Printing micro / nano structures

[0070] The controller 4 controls the movement speed and distance of the X-axis 1, Y-axis 2, and Z-axis 3, with a movement speed of 0.1-30 mm / s, a movement distance of 0-60 mm, and a printing layer count of 0-10 layers. The temperature controller 18 controls the temperature of the heating plate 22, with a heating temperature of 30-80℃, to heat the target object 5 and accelerate the curing of the transverse jet 7. Finally, the printing of the micro-nano structure 6 is completed, with a linewidth of 200 nm-300 μm.

[0071] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. An electric field-constrained transverse electrojet printing device, comprising an XYZ three-dimensional motion platform and a heating module, wherein the XYZ three-dimensional motion platform includes an X-axis, a Y-axis, a Z-axis, and a controller, characterized in that: The printing device further includes a transverse electrojet printing module and a confined electric field generating module; the heating module includes a temperature controller and a heating plate. The horizontal electrojet printing module includes a Luer needle adapter, a right-angle nozzle, a needle clamp, a tubing, a syringe, a micro-feed pump, and a high-voltage drive electric field generator. The Luer needle adapter and the right-angle nozzle are connected by threads. The high-voltage end of the high-voltage drive electric field generator is connected to the right-angle nozzle, and the ground end is connected to the target object, creating a potential difference between the right-angle nozzle and the target object. The syringe is fixed to the micro-feed pump, contains ink, and is connected to the Luer needle adapter via a tubing. The vertical section of the right-angle nozzle is connected to the Luer needle adapter, the horizontal section of the right-angle nozzle faces the target object, and the end of the horizontal section is the outlet of the right-angle nozzle. The confined electric field generating module includes a high-voltage confined electric field generating power supply, a near-end laser generator, a far-end laser generator, an electrode plate, a near-end laser receiver, a far-end laser receiver, and an insulating pad; the high-voltage end of the high-voltage confined electric field generating power supply is connected to the electrode plate, and the ground end is connected to the target object, so that the electrode plate and the right-angle nozzle have electric fields of the same polarity. The near-end laser generator and near-end laser receiver are placed at the starting point of the jet, and the far-end laser generator and far-end laser receiver are placed at the ending point of the jet. The high-voltage confinement electric field power supply, near-end laser generator, far-end laser generator, near-end laser receiver, and far-end laser receiver are all electrically connected to the confinement control unit and are used to adjust the confinement electric field strength according to the laser detection results. An L-shaped connecting plate is fixedly installed on the Z-axis. The vertical surface of the L-shaped connecting plate is fixed to the Z-axis, and the horizontal surface supports the electrode plate, insulating pad, heating plate, and target object. A heating plate and an insulating pad are arranged sequentially from bottom to top on the horizontal surface of the L-shaped connecting plate. A groove for placing an electrode plate is provided on the side of the insulating pad away from the Z-axis. The electrode plate is placed in the groove of the insulating pad, and the target object is fixed on the side of the insulating pad without a groove. The distance from the horizontal end of the right-angle nozzle to the target object is on the order of millimeters. Laser sensors are installed at the same height at the starting and ending points of the transverse ink jet. The laser sensors detect the height difference between the starting and ending points of the transverse jet in real time. The constrained electric field control program is as follows: set the voltage adjustment step size k and the height difference threshold h0 of the constrained electric field, and obtain the height difference between the start and end points of the transverse jet in real time; Given the initial field strength of the constraint electric field, obtain the height difference, and adjust the field strength of the constraint electric field in real time according to the set voltage adjustment step size k based on the height difference until the height difference is controlled within the set height difference threshold h0. Record the constraint electric field strength and polarity at this time. Side surface micro / nano structures are printed under the electric field strength and polarity constraints required for the current ink lateral jet printing, as determined by the constrained electric field control program. The height difference threshold h0 is no greater than 100μm. When the height difference is within the range of (-h0, h0), the output constraint electric field strength and polarity are determined. The voltage adjustment step size k is adjusted within the range of 10-100V. First, apply the constraint electric field gradually according to the step size k0 and calculate the height difference in real time; determine whether the height difference is greater than the first height difference threshold h1. If it is greater, set the voltage adjustment step size to the first voltage adjustment step size k1. If the height difference is not greater than the first height difference threshold h1, then determine whether the height difference is greater than the second height difference threshold h2. If it is greater, then set the voltage adjustment step size to the second voltage adjustment step size k2. If the height difference is not greater than the second height difference threshold h2, then determine whether the height difference is greater than the third height difference threshold h3. If it is greater, then set the voltage adjustment step size to the third voltage adjustment step size k3, until the jet height difference reaches the range of (-h0, h0). k0 is 500V, and k1, k2, and k3 are taken in the range of 10-100V; h is the height difference between the start and end points of the jet when no constraint electric field is applied; h1 is h / 2, h2 is h / 5, and h3 is h / 10; the height difference is the height of the start point minus the height of the end point. When the height difference is positive, the constraint electric field strength is increased by a step size, and when the height difference is negative, the constraint electric field strength is decreased by a step size.

2. The electric field-constrained transverse electrojet printing apparatus according to claim 1, characterized in that, The printing device is also equipped with a CCD high-speed camera for real-time monitoring of the jet morphology; the constraint control unit is a PC or an MCU microcontroller.

3. The electric field-constrained transverse electrojet printing apparatus according to claim 1, characterized in that, The X and Y motion axes use SURUGA SEIKI KXL06050 series motion axes with a travel range of 0-50mm, a speed range of 0-30mm / s, a resolution of 0.2μm, and a repeatability of 0.5μm; the Z motion axis uses SURUGA SEIKI KZL06050 series motion axes with a travel range of 0-50mm, a speed range of 0-30mm / s, a resolution of 0.2μm, and a repeatability of 0.5μm. The inner diameter of the right-angle nozzle is 80-300μm; the micro-feed pump adopts the Harvard Pump 11 Elite series feed pump, with a feed rate of 3.66pl / min-3.82ml / min, a stability accuracy of 0.35%, and a reproducibility accuracy of 0.05%; the high-voltage drive electric field generator power supply adopts the Dongwen high-voltage DW-P303 series high-voltage power supply, with an output voltage range of 0-30kV and a resolution of 1V. The high-voltage confinement electric field generator uses the Dongwen DW-P303 series high-voltage power supply, with an output voltage range of 0-30kV and a resolution of 1V. The electrode plate is 80mm long, 40mm wide, and 1mm thick, and is connected to the insulating pad by adhesive. The insulating pad is 80mm long, 80mm wide, and 2mm thick, and has a groove of 80mm long, 40mm wide, and 1mm deep milled on its upper surface for placing the electrode plate. The heating plate is 80mm long, 80mm wide, and 2mm thick. It has an embedded resistance wire and a temperature sensor, and is connected to a temperature controller. The temperature controller has a temperature control range of 30-80℃ and a resolution of 1℃.

4. The electric field-constrained transverse electrojet printing apparatus according to claim 3, characterized in that, The electrode plate is made of stainless steel, the insulating pad is made of alumina ceramic, the heating plate is made of brass, and the right-angle nozzle is made of stainless steel.

5. A transverse electrojet printing method under electric field constraint, characterized in that, The printing method employs the electric field-constrained transverse electrojet printing device as described in claim 2, and the printing method steps are as follows: Step 1: Lateral jet formation First, place the target object on an insulating mat, use a syringe to draw ink and fix it on a micro-feed pump, use the micro-feed pump to precisely control the flow rate, and deliver the ink in the syringe to the right-angle nozzle through a tubing and Luer needle adapter; The electric field strength between the right-angle nozzle and the target object is controlled by a high-voltage driving electric field power source. The ink forms a transverse jet under the combined action of driving electric field force, feed pressure and surface tension. Step 2: Constraining the electric field In the absence of a constrained electric field, the transverse jet is deflected downwards by gravity, deviating from its predetermined position. Utilizing the jet's blocking effect on the laser, a near-end laser generator and a near-end laser receiver detect the height of the jet's starting point, while a far-end laser generator and a far-end laser receiver detect the height of the jet's ending point. The results are input into the constraint control unit. Based on the height difference between the starting and ending points of the transverse jet, the constraint control unit automatically sends a signal to the high-voltage constraint electric field generator. The high-voltage constraint electric field generator applies a high-voltage electric field with the same polarity as the ink to the electrode plate. According to the principle of like poles repulsion, the transverse jet is deflected upwards by the repulsive force of the constraint electric field, thus counteracting gravity. Increasing the confining electric field strength increases the repulsive force on the transverse jet and increases its upward deflection; decreasing the confining electric field strength decreases the repulsive force on the transverse jet and decreases its upward deflection. The confining electric field strength is automatically adjusted based on the height difference between the starting and ending points of the transverse jet, ensuring that the transverse jet is precisely deposited at a predetermined location. A CCD high-speed camera is used to monitor the jet morphology in real time. Step 3: Printing micro / nano structures The magnitude of the confinement electric field is adjusted so that the starting and ending points of the transverse jet are at the same height, at which point the confinement electric field completely cancels out the influence of gravity; the X, Y, and Z axes are controlled by a controller to move according to a predetermined program; the heating temperature is controlled by a temperature controller to heat the target object and accelerate the solidification of the transverse jet; finally, the printing of the micro-nano structure is completed.

6. The electric field-constrained transverse electrojet printing method according to claim 5, characterized in that, The linewidth of the micro-nano structure is 200nm-300μm, and the printing accuracy is controlled within 100μm.

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