Aerosol jet printing device and method capable of achieving quick cut-off

Abstract

The invention belongs to the field of additive manufacturing, and particularly discloses an aerosol jet printing device and method capable of achieving quick cut-off, and the device comprises a jet printing head unit and a vacuum cut-off unit. Wherein the jet printing head unit comprises an aerosol beam channel, an aerosol channel and a sheath gas channel which are connected with an inlet of the aerosol beam channel, and a nozzle connected with an outlet of the aerosol beam channel; the vacuum cut-off unit comprises a cut-off channel and a vacuumizing assembly, one side of the cut-off channel is connected with an external hollow pipe arranged beside the outlet of the nozzle or connected with the aerosol beam channel, and the other side of the cut-off channel is connected with the vacuumizing assembly, so that negative pressure is formed under the action of the vacuumizing assembly; and aerosol in the aerosol beam channel is sucked into the cut-off channel so as to realize rapid cut-off. High-responsivity cut-off of the aerosol beam is achieved by changing the flowing direction of the aerosol beam, the device is simple in structure and high in cut-off responsivity, the limitation of the jet printing device on the jet printing substrate structure is greatly reduced, and the application range is wide.

Description

Technical Field

[0001] The present application belongs to the field of additive manufacturing, and more specifically, to a fast-cutoff aerosol printing device and method. Background Art

[0002] In recent years, the electronics industry has gradually developed towards lightweight, miniaturization and integration. In particular, electronic products printed on flexible and curved substrates account for an increasing proportion in the wearable device, intelligent integrated device and intelligent packaging market. However, traditional printed electronic devices need to be improved in terms of manufacturing accuracy, integration and electrical performance. In response to the growing demand, high-resolution printed electronics technology has gradually grown. As an emerging non-contact additive manufacturing technology, aerosol printing technology has many technical advantages such as high manufacturing resolution, low material loss, high printing speed and good substrate adaptability. It has been widely used in consumer electronics, medical electronics, aerospace and other fields. The workflow of aerosol printing is: first, the raw material is atomized into micron-sized particles; then, an aerosol beam is formed under the action of carrier gas carrying and sheath gas wrapping and constraint; finally, the aerosol beam is ejected from the nozzle at a certain speed and deposited on the substrate to realize the printing of the designed pattern. By adjusting the size and ratio of the carrier gas and sheath gas, the molding parameters such as line width and thickness of the printed line can be adjusted. Theoretically, the minimum line width can reach 10μm.

[0003] In addition to the line width accuracy of aerosol printing, the start-stop responsiveness of aerosol printing is also an important factor affecting the overall printing quality. When printing starts, the carrier gas is input to transport the aerosol flow to be deposited on the substrate; when printing ends, the carrier gas input stops, causing the aerosol to be cut off. However, since the decrease and increase of the air pressure in the print head are both gradual processes, there is a large time delay in the response of the aerosol beam when starting and stopping, and it takes a certain amount of time to reach a stable state. That is, the start-stop responsiveness of aerosol printing is low, which seriously affects the further application of this technology in fine pattern manufacturing. At present, there are two main solutions to improve the start-stop responsiveness of aerosol printing: (1) blocking the aerosol beam outside the aerosol printing head, that is, by configuring a mechanical baffle and control system externally, as shown in the article "Conformal printing of sensors on 3D and flexible surfaces using aerosol jet deposition", Proc. SPIE 8691, Nanosensors, Biosensors, and Info-Tech Sensors and Systems 2013, 86910P (9 April 2013), when the aerosol printing stops, the control system gives a signal, and the external mechanical baffle moves to the bottom of the nozzle to prevent the aerosol beam from being deposited on the substrate surface below; when the aerosol printing starts, the mechanical baffle moves away from under the nozzle. In this solution, the start-stop responsiveness of aerosol printing can reach 2ms, but the external mechanical baffle and control system undoubtedly increase the complexity of the printing system, and the repeated acceleration and deceleration may also cause substrate contamination. More importantly, when aerosol printing stops, the mechanical baffle will move to the position directly below the nozzle, resulting in a working distance between the nozzle and the substrate greater than 5 mm, far exceeding the optimal focusing point of the aerosol beam ejected from the nozzle, greatly affecting the printing effect. (2) Cut off the aerosol flow inside the aerosol printing head, that is, control the flow direction of the gas during start and stop by designing a flow channel structure inside the printing head. When aerosol printing stops, the sheath gas no longer enters the printing head from the sheath gas flow channel, but instead enters the bottom of the gas collection chamber from the side flow channel. A portion of the sheath gas is deflected in the direction opposite to the flow direction of the aerosol flow, causing the aerosol flow to reverse and prevent it from flowing to the nozzle, thereby achieving the cutoff of the aerosol flow, as shown in the aerosol flow blocking disclosed in CN111655382B. However, in this scheme, in addition to a part of the sheath gas entering the bottom of the gas collection chamber from the side flow channel being deflected to the direction opposite to the flow direction of the aerosol flow, another part will be deflected to the direction same as the flow direction of the aerosol flow and ejected from the nozzle, which will produce a greater airflow impact on the substrate and affect the integrity of the printed pattern. Summary of the invention

[0004] In view of the defects of the prior art, the present application provides an aerosol printing device and method with rapid shutoff, aiming to solve the problem that the shutoff mode of the existing aerosol printing device affects the printing effect.

[0005] According to one aspect of the present application, there is provided an aerosol printing device that can be quickly cut off, specifically comprising a print head unit and a vacuum cutoff unit, wherein: the print head unit comprises an aerosol beam channel, an aerosol channel and a sheath gas channel connected to the inlet of the aerosol beam channel, and a nozzle connected to the outlet of the aerosol beam channel; the vacuum cutoff unit comprises a cutoff channel and a vacuum pumping component, one side of the cutoff channel is connected to an external hollow tube arranged beside the nozzle outlet or to the aerosol beam channel, and the other side is connected to the vacuum pumping component to form a negative pressure under the action of the vacuum pumping component, so that the aerosol in the aerosol beam channel is sucked into the cutoff channel to achieve rapid cutoff.

[0006] The above technical scheme conceived by the present application, compared with the prior art, because the present application sets a vacuum cutoff unit in the aerosol printing device, can use negative pressure to intercept the aerosol and change the flow direction, thereby achieving rapid cutoff of the aerosol beam, and has the advantages of high responsiveness, simple structure, and avoiding contamination of the substrate.

[0007] As further preferred, the vacuum assembly includes a filter, a raw material recovery device and a vacuum pump, the filter is arranged between the cut-off channel and the vacuum pump, and the filter is connected to the raw material recovery device, and is used to deliver the aerosol in the cut-off channel into the raw material recovery device under the suction action of the vacuum pump.

[0008] As further preferred, the vacuum pumping assembly further includes a solenoid valve, which is disposed between the filter and the vacuum pump and is used to control the opening and closing of the channel between the vacuum pump and the filter.

[0009] As further preferred, the vacuum pumping assembly further includes a pressure regulating valve, which is arranged between the solenoid valve and the filter and is used for regulating pressure.

[0010] As a further preferred embodiment, when the cut-off channel is connected to the external hollow tube, the distance H2 between the lowest horizontal point of the external hollow tube and the lowest horizontal point of the nozzle is less than 5 mm, and the inner diameter D2 of the external hollow tube near the nozzle end is not less than the inner diameter D1 of the nozzle.

[0011] As further preferred, when the cutoff channel is connected to the aerosol beam channel, the cutoff channel is a circular pipe, the inner diameter D4 of the cutoff channel is equal to the inner diameter D3 of the aerosol beam channel, and the inner diameter D4 of the cutoff channel is larger than the inner diameter D1 of the nozzle.

[0012] As a further preferred embodiment, when the cutoff channel is connected to the aerosol beam channel, the cutoff channel is a non-circular pipe, the height H1 of the cutoff channel is not less than the inner diameter D3 of the aerosol beam channel, the width W of the cutoff channel is not greater than the inner diameter D3 of the aerosol beam channel, and the width W of the cutoff channel is greater than the inner diameter D1 of the nozzle.

[0013] According to another aspect of the present application, a rapid cut-off method for the above-mentioned aerosol printing device is provided, specifically: the print head unit is started for printing, and when it is necessary to switch to the cut-off state, the vacuum pumping component is turned on, thereby forming a negative pressure in the cut-off channel, so as to suck the aerosol in the aerosol beam channel into the cut-off channel to achieve rapid cut-off, and the vacuum pumping component is closed when it is necessary to switch to the printing state.

[0014] As a further preference, when the vacuum pumping component includes a solenoid valve, the vacuum pump is in a normally open state, and the opening and closing of the vacuum component is controlled by opening or closing the solenoid valve; or, the vacuum pump and the solenoid valve are opened or closed synchronously to control the opening and closing of the vacuum component.

[0015] As a further preferred embodiment, when the cut-off channel is connected to the aerosol beam channel, the negative pressure P generated by the cut-off channel in the cut-off state is N The following conditions need to be met:

[0016]

[0017] Where A is the area of ​​the intersection of the cutoff channel and the aerosol beam channel, g is the gravitational acceleration, m is the mass of the aerosol particles, H1 is the height of the cutoff channel, when the cutoff channel is a circular pipe, the inner diameter of the cutoff channel is its height, θ2 is the angle between the cutoff channel and the aerosol beam channel, Q is the sum of the sheath gas flow rate and the carrier gas flow rate, D3 is the inner diameter of the aerosol beam channel, and D5 is the diameter of the aerosol flow in the aerosol beam channel.

[0018] In general, the above technical solutions conceived by this application have the following technical advantages compared with the prior art:

[0019] 1. The present application sets a vacuum cut-off unit, which can divert and intercept the aerosol beam in the path of the aerosol beam, and realizes high-responsiveness cut-off of the aerosol beam by changing the flow direction of the aerosol beam. The device has a simple structure and high cut-off responsiveness, which greatly reduces the restriction of the printing device on the structure of the printing substrate and has a wide range of applications. Compared with the traditional mechanical baffle blocking solution, the space occupied by the external mechanical baffle and its support and control module on the side of the printing head is greatly reduced, and the applicability of the aerosol printing technology to non-planar substrates is improved. At the same time, it also greatly avoids the risk of raw material overflow on the external mechanical baffle and the risk of raw material being thrown onto the substrate due to acceleration and deceleration of the external mechanical baffle, causing contamination. At the same time, compared with the traditional pneumatic blocking solution, the problem of aerosol flow diversion delay caused by gas diversion in the printing head is avoided, and the cut-off responsiveness can reach 2ms. At the same time, the present application cuts off the entire aerosol beam, so that no airflow flows out of the nozzle when the printing stops, avoiding the impact on the substrate and the influence on the printed pattern, so that the aerosol printing accuracy and process stability are greatly improved.

[0020] 2. At the same time, the present application optimizes the structure of the vacuum pumping component and uses a solenoid valve to control the opening and closing of the vacuum cutoff unit, which can further improve the cutoff responsiveness and simplify the control process;

[0021] 3. In particular, the present application optimizes the size of the cutoff channel according to its installation position and shape, and adjusts the negative pressure in the vacuum cutoff unit to a corresponding range when in use, thereby achieving complete cutoff of the aerosol beam while ensuring the cutoff responsiveness and startup responsiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of an aerosol printing device with rapid cutoff provided in one embodiment of the present application;

[0023] Figure 2 yes Figure 1 An enlarged view of the nozzle and the cutoff channel in the aerosol printing device is provided;

[0024] Figure 3 yes Figure 1 A schematic diagram of the fluid flow direction and aerosol distribution when the aerosol printing device is switched to a cut-off state is provided;

[0025] Figure 4 yes Figure 1 A schematic diagram of the fluid flow direction and aerosol distribution when the aerosol printing device is switched to the printing state is provided;

[0026] Figure 5 is a schematic structural diagram of an aerosol printing device capable of rapid shutoff provided by another embodiment of the present application;

[0027] Figure 6 yes Figure 5 A schematic diagram of the fluid flow direction and aerosol distribution when the aerosol printing device is switched to a cut-off state is provided;

[0028] Figure 7 yes Figure 5 A simulation result diagram of aerosol distribution fluid when the provided aerosol printing device is switched to a cut-off state;

[0029] Figure 8 yes Figure 5 A schematic diagram of the fluid flow direction and aerosol distribution when the aerosol printing device is switched to the printing state is provided;

[0030] Fig. 9 yes Figure 5 A simulation result diagram of aerosol distribution fluid when the provided aerosol printing device is switched to the printing state;

[0031] Fig.10 yes Figure 5 A cross-sectional view of a print head unit when the cut-off channel in the provided aerosol printing device is a non-circular channel;

[0032] Fig.11 It is a structural schematic diagram of an aerosol printing device with rapid cutoff provided by another embodiment of the present application;

[0033] Fig.12 It is a schematic structural diagram of an aerosol printing device with rapid shutoff provided in yet another embodiment of the present application.

[0034] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0035] 1-aerosol channel, 2-sheath gas inlet, 3-sheath gas channel, 4-gas collection chamber, 5-aerosol beam channel, 6-cut-off channel, 7-solenoid valve, 8-filter, 9-raw material recovery device, 10-nozzle, 11-substrate, 12-vacuum pump, 13-pressure regulating valve, 14-external hollow tube. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0037] like Figures 1 to 12As shown, the present application provides an aerosol printing device that can be quickly cut off, specifically including a printing head unit and a vacuum cut-off unit, wherein: the printing head unit includes an aerosol beam channel 5, an aerosol channel 1 and a sheath gas channel 3 connected to the inlet of the aerosol beam channel 5, and a nozzle 10 connected to the outlet of the aerosol beam channel 5, and the inner diameter D2 of the nozzle 10 is 0.05mm-5mm; the aerosol channel 1 is used to pass a carrier gas carrying aerosol particles, the sheath gas channel 3 is a sheath gas delivery channel formed inside the shell, and the sheath gas channel 3 is provided with a sheath gas inlet 2 for passing sheath gas, the aerosol channel 1 and the sheath gas channel 3 are mixed in the gas converging chamber 4, the sheath gas surrounds the aerosol flow to form an aerosol beam and is sent into the aerosol beam channel 5, and finally sprayed out from the nozzle 10; Figure 1 , 10 The middle sheath gas channel 3 surrounds the gas collection chamber 4, and the sheath gas channel 3 is openly connected with the gas collection chamber 4. Figure 5 , Fig.12 The middle sheath gas channel 3 is connected to the gas collection chamber 4 in a closed manner, and the sheath gas channel 3 can also be connected to the gas collection chamber 4 in any other manner;

[0038] The vacuum cut-off unit includes a cut-off channel 6 and a vacuum pumping assembly. One side of the cut-off channel 6 is connected to an external hollow tube 14 arranged beside the nozzle 10 outlet or to the aerosol beam channel 5, and the other side is connected to the vacuum pumping assembly to form a negative pressure under the action of the vacuum pumping assembly, so that the aerosol in the aerosol beam channel 5 is sucked into the cut-off channel 6 to achieve rapid cut-off, wherein Figure 1 and Fig.12 This is an embodiment in which the cut-off channel 6 is connected to the external hollow tube 14. Figure 5 , Fig.11 This is an embodiment in which the cutoff channel 6 is connected to the aerosol beam channel 5 .

[0039] The present application sets a vacuum cutoff unit, which can divert and intercept the aerosol beam in the path of the aerosol beam, and realizes high-responsiveness cutoff of the aerosol beam by changing the flow direction of the aerosol beam. The device has a simple structure and high cutoff responsiveness, which greatly reduces the restrictions of the printing device on the structure of the printing substrate and has a wide range of applications. Compared with the traditional mechanical baffle blocking solution, it greatly reduces the space occupied by the external mechanical baffle and its support and control module on the side of the printing head, improves the applicability of aerosol printing technology to non-planar substrates, and also greatly avoids the risk of raw material overflow on the external mechanical baffle and the risk of raw material being thrown onto the substrate and causing contamination due to acceleration and deceleration of the external mechanical baffle. Compared with the traditional pneumatic blocking solution, it avoids the problem of aerosol flow diversion delay caused by gas diversion in the printing head, and the cutoff responsiveness can reach 2ms. At the same time, the present application cuts off the entire aerosol beam, so that no airflow flows out of the nozzle when printing stops, avoiding the impact on the substrate and the influence on the printed pattern, so that the aerosol printing accuracy and process stability are greatly improved.

[0040] Furthermore, the vacuum assembly includes a filter 8, a raw material recovery device 9 and a vacuum pump 12. The filter 8 is arranged between the cut-off channel 6 and the vacuum pump 12, and the filter 8 is connected to the raw material recovery device 9 for delivering the aerosol in the cut-off channel 6 into the raw material recovery device 9 under the suction action of the vacuum pump 12.

[0041] Furthermore, the vacuum pumping assembly further includes a solenoid valve 7, which is disposed between the filter 8 and the vacuum pump 12 and is used to control the opening and closing of the channel between the vacuum pump 12 and the filter 8. After the solenoid valve 7 is added, the vacuum pumping assembly has two control modes, one of which is that the vacuum pump 12 adopts a normally open mode, and only the solenoid valve 7 is used to control the opening and closing of the vacuum pumping assembly, and this control mode is more convenient and fast; the other is that the vacuum pump 12 and the solenoid valve 7 are opened and closed synchronously, and this control mode is more reliable.

[0042] Furthermore, the vacuum pumping component also includes a pressure regulating valve 13, which is arranged between the solenoid valve 7 and the filter 8 and is used to adjust the pressure. The pressure regulating valve 13 is used to adjust the negative pressure value in the cut-off channel 6 to within the negative pressure value range corresponding to the cut-off channel size parameter, thereby achieving complete cut-off of the aerosol beam flow while ensuring the cut-off responsiveness and start-up responsiveness.

[0043] Further, when the cut-off channel 6 is connected to the external hollow tube 14, the angle θ1 between the external hollow tube 14 and the center line of the nozzle 10 is greater than 0° and less than 180°, so as to ensure that the negative pressure generated by the external hollow tube 14 has a component in the direction perpendicular to the center line of the nozzle 10 when the aerosol beam is cut off, and θ1 is preferably 90°, and the external hollow tube 14 cannot be on the path of the aerosol beam outside the nozzle 10. The distance H2 between the lowest horizontal point of the external hollow tube 14 and the lowest horizontal point of the nozzle 10 is less than 5mm, so as to avoid the distance between the nozzle 10 and the substrate 11 being greater than 5mm, and the inner diameter D2 of the end of the external hollow tube 14 close to the nozzle 10 is not less than the inner diameter D1 of the nozzle 10. When the aerosol beam is cut off, the absolute value of the negative pressure generated by the vacuum assembly in the cut-off channel 6 is greater than the absolute value of the internal pressure in the nozzle 10, so that all the aerosol particles in the aerosol beam channel 5 can be sucked into the cut-off channel 6.

[0044] Further, when the cut-off channel 6 is connected to the aerosol beam channel 5, as Figure 2 As shown, the cutoff channel 6 is composed of one or more channels of different sizes, and the angle θ2 between the cutoff channel 6 connected to the aerosol beam channel 5 and the aerosol beam channel 5 is greater than 0° and less than 180°. Preferably, θ2 is 90°, so that the aerosol beam flows out from the cutoff channel 6 instead of the nozzle 10 when the vacuum assembly is adjusted to the negative pressure range corresponding to the size parameters of the cutoff channel.

[0045] When the cut-off channel 6 is a circular pipe, Figure 5 As shown, the inner diameter D4 of the cut-off channel 6 is equal to the inner diameter D3 of the aerosol beam channel 5 , and the inner diameter D4 of the cut-off channel 6 is greater than the inner diameter D1 of the nozzle 10 .

[0046] When the cut-off channel 6 is a non-circular pipe, Fig.10 The opening of the middle aerosol beam channel 5 is the cross-sectional shape of the cut-off channel. The height H1 of the cut-off channel 6 is not less than the inner diameter D3 of the aerosol beam channel 5. The width W of the cut-off channel 6 is not greater than the inner diameter D3 of the aerosol beam channel 5 to ensure that the aerosol beam has a lower Reynolds number Re, so that it can all flow out from the cut-off channel 6 instead of flowing out from the nozzle 10 even under a lower negative pressure. At the same time, the width W of the cut-off channel 6 is greater than the inner diameter D1 of the nozzle 10.

[0047] The specific process of high-precision preparation using the aerosol printing device provided in this application is as follows:

[0048] (1) Figure 1 or Figure 5As shown, aerosol printing is started, the sheath gas and the carrier gas are turned on, the sheath gas is introduced from the sheath gas inlet 2, passes through the sheath gas channel 3 and the gas collection chamber 4 and enters the aerosol beam channel 5, the carrier gas carries the aerosol particles to form an aerosol flow, and enters the aerosol beam channel 5 from the aerosol channel 1 through the gas collection chamber 4; the sheath gas surrounds the aerosol flow in the middle to form an aerosol beam flow, which flows through the nozzle 10 and is deposited on the surface of the lower substrate 11, at this time, the solenoid valve 7 is in a closed state, and the vacuum pump 12 is kept normally open or switched synchronously with the solenoid valve 7;

[0049] (2) adjusting the flow rate and ratio of the delivered carrier gas and sheath gas according to the set parameters, adjusting the height of the nozzle 10 from the substrate 11, the printing speed and other parameters until the printing effect reaches a stable state; wherein the carrier gas flow rate is 0 sccm to 500 sccm, the sheath gas flow rate is 0 sccm to 1000 sccm, the height of the nozzle 10 from the substrate 11 is 0 mm to 5 mm, and the printing speed is 0.1 mm / s to 100 mm / s;

[0050] (3) According to the set printing pattern trajectory requirements, when it is necessary to cut off the aerosol beam, such as Figure 3 or Figure 6 As shown, the solenoid valve 7 is opened to form a negative pressure in the cut-off channel 6. The negative pressure value meets the negative pressure range requirements corresponding to different cut-off flow channel size parameters, so that the aerosol beam is sucked into the cut-off channel 6 before being deposited on the surface of the substrate 11, thereby realizing the cut-off of the aerosol beam; during the printing process, the aerosol beam can be quickly cut off at different flow rates by adjusting the negative pressure;

[0051] (4) According to the set printing pattern trajectory requirements, when it is necessary to start aerosol printing, Figure 4 or Figure 8 As shown, the electromagnetic valve 7 is closed, and the aerosol beam switches its path again, flows through the nozzle 10 and is directly deposited on the surface of the substrate 11 below, and the aerosol printing process is restarted;

[0052] (5) Repeat the above steps (3) and (4) to achieve high-precision preparation of the set pattern. Figure 7 and Fig. 9 They are respectively a diagram of aerosol distribution fluid simulation result when the aerosol printing device is switched to the cut-off state and a diagram of aerosol distribution fluid simulation result when the aerosol printing device is switched to the printing state, which proves the feasibility and reliability of the present application.

[0053] According to another aspect of the present application, a rapid cut-off method for the above-mentioned aerosol printing device is provided, specifically: starting the print head unit, the sheath gas surrounds the aerosol flow to form an aerosol beam, which flows through the nozzle 10 and is deposited on the surface of the lower substrate 11. When switching to the cut-off state, the vacuum pumping component is turned on to form a negative pressure in the cut-off channel 6, and the negative pressure is adjusted to within a set range to suck the aerosol in the aerosol beam channel 5 into the cut-off channel 6 to achieve rapid cut-off. When restarting is required, the vacuum pumping component is closed, and the aerosol beam switches the path again, flows through the nozzle 10 and is directly deposited on the surface of the lower substrate 11. Repeating the above steps can achieve high-precision preparation of the image.

[0054] Furthermore, if the vacuum pumping assembly does not include a solenoid valve, when the vacuum pumping assembly is opened, the vacuum pump 12 is turned on; when the vacuum pumping assembly is closed, the vacuum pump 12 is turned off.

[0055] If the vacuum pumping assembly includes a solenoid valve, when the vacuum pumping assembly is opened, the vacuum pump 12 and the solenoid valve 7 are turned on, and when the vacuum pumping assembly is closed, the vacuum pump 12 can be kept turned on and the solenoid valve 7 can be closed, or the vacuum pump 12 and the solenoid valve 7 can be closed simultaneously. It is faster and more convenient to control the opening and closing operation of the vacuum pumping assembly only by the solenoid valve 7.

[0056] Furthermore, when the cut-off channel 6 is connected to the aerosol beam channel 5, when the aerosol beam is cut off, the negative pressure generated by the vacuum pumping component in the cut-off channel 6 should make all the aerosol particles in the aerosol beam channel 5 be sucked into the cut-off channel 6, that is, the negative pressure generated by the vacuum pumping component in the cut-off channel 6 is P N Need to meet:

[0057]

[0058] Wherein, A is the area of ​​the intersection surface between the cutoff channel 6 and the aerosol beam channel 5, g is the gravitational acceleration, m is the mass of the aerosol particles, H1 is the height of the cutoff channel 6, when the cutoff channel 6 is a circular pipe, the inner diameter of the cutoff channel 6 is its height, θ2 is the angle between the cutoff channel 6 and the aerosol beam channel 5, Q is the sum of the sheath gas flow rate and the carrier gas flow rate, D3 is the inner diameter of the aerosol beam channel 5, and D5 is the diameter of the aerosol flow in the aerosol beam channel 5.

[0059] The aerosol beam consists of an aerosol flow and an annular sheath flow surrounding the aerosol flow. The maximum value D5 of the diameter D5 of the aerosol flow in the aerosol beam channel 5 is max is equal to the diameter D3 of the aerosol beam channel, that is, the negative pressure P generated by the vacuum component in the cut-off channel 6 N Also need to meet:

[0060]

[0061] When the negative pressure P generated by the vacuum pumping component in the cut-off channel 6 is N When it continues to grow, the aerosol particles can still be completely sucked into the cutoff channel 6, but the internal pressure of the flow channel inside the print head (including the aerosol beam channel 5, the cutoff channel 6, the aerosol channel 1, and the sheath gas channel 3) will be too low, resulting in a large time delay when the aerosol printing is started.

[0062] In summary, when the cut-off channel 6 is connected to the aerosol beam channel 5, when the aerosol beam is cut off, the negative pressure P generated by the vacuum pump in the cut-off channel 6 is N It is necessary to satisfy both equation (1) and equation (2), namely:

[0063]

[0064] The technical solution provided in this application is further described below based on specific embodiments.

[0065] Example 1

[0066] A fast-cutoff aerosol printing device comprises a printing head unit and a vacuum cutoff unit. The printing head unit comprises an aerosol beam channel 5, an aerosol channel 1, a sheath gas channel 3 and a nozzle 10. The vacuum cutoff unit comprises a cutoff channel 6 and a vacuum pumping component. One side of the cutoff channel 6 is connected to an external hollow tube 14, and the other side thereof is connected to the vacuum pumping component.

[0067] Among them, the inner diameter D1 of the nozzle 10 is 0.15mm. The external hollow tube 14 is located on the side of the nozzle 10, one end is adjacent to the nozzle 10, and the other end is connected to the cut-off channel 6 through a thread. The center line of the flow channel at the end of the external hollow tube 14 and the center line of the flow channel of the nozzle 10 are at an angle θ1=90°, the horizontal spacing L1 between the end of the external hollow tube 14 and the nozzle 10 is 0mm, the outlet inner diameter D2 of the external hollow tube 14 is 0.5mm, and the distance H2 between the lowest horizontal point of the external hollow tube 14 and the lowest horizontal point of the nozzle 10 is 0.55mm.

[0068] The rapid cut-off method of the aerosol printing device specifically comprises the following steps:

[0069] (1) Start aerosol printing, turn on the sheath gas and carrier gas, the sheath gas enters the aerosol beam channel 5 from the sheath gas channel 3 through the gas collection chamber 4, the carrier gas carries the aerosol particles to form an aerosol flow, and enters the aerosol beam channel 5 from the aerosol channel 1 through the gas collection chamber 4. The sheath gas surrounds the aerosol flow in the middle to form an aerosol beam flow, which flows through the nozzle 10 and is deposited on the substrate surface below. At this time, the solenoid valve 12 is in a closed state, and the vacuum pump 12 remains normally open;

[0070] (2) According to the set parameters, the carrier gas flow rate is adjusted to 20 sccm, the sheath gas flow rate is adjusted to 50 sccm, the height of the nozzle 10 from the substrate 11 is adjusted to 5 mm, and the printing speed is adjusted to 5 mm / s until the printing effect reaches a stable state;

[0071] (3) According to the set printing pattern trajectory requirements, when the aerosol beam needs to be cut off, the solenoid valve 7 is opened to form a negative pressure in the cut-off channel 6 and the external hollow tube 14. The pressure in the external hollow tube 14 is -10 kPa. After the aerosol beam flows through the nozzle 10, it switches the path and is sucked into the external hollow tube 14 and enters the cut-off channel 6. The raw material passes through the filter 8 and enters the raw material recovery device 9, thereby preventing the aerosol beam from being deposited on the surface of the substrate 11, thereby achieving the cut-off of the aerosol beam;

[0072] (4) According to the set printing pattern trajectory requirements, when it is necessary to start aerosol printing, the solenoid valve 7 is closed, and the aerosol beam flows through the nozzle 10 and switches the path again, and is directly deposited on the surface of the lower substrate 11, and the aerosol printing process is restarted;

[0073] (5) Repeat the above steps (3) and (4) to achieve high-precision preparation of the set pattern.

[0074] Example 2

[0075] A fast-cutoff aerosol printing device comprises a printing head unit and a vacuum cutoff unit. The printing head unit comprises an aerosol beam channel 5, an aerosol channel 1, a sheath gas channel and a nozzle 10. The vacuum cutoff unit comprises a cutoff channel 6 and a vacuum pumping component. One side of the cutoff channel 6 is connected to the aerosol beam channel 5, and the other side is connected to the vacuum pumping component.

[0076] The inner diameter of the nozzle is D1 = 0.5 mm. The diameter of the aerosol beam channel 5 is D3 = 1.5 mm. The cut-off channel 6 is composed of a section of the channel, and the cross section of the channel is circular. The cross section diameter of the cut-off channel 6 is D4 = D3 = 1.5 mm. The length of the cut-off channel 6 is L2 = 15 mm. The angle θ2 at which the cut-off channel 6 and the aerosol beam channel 5 are connected is 90°.

[0077] The rapid cut-off method of the aerosol printing device specifically comprises the following steps:

[0078] (1) Start aerosol printing, turn on the sheath gas and carrier gas, the sheath gas enters the aerosol beam channel 5 from the sheath gas channel 3 through the gas collection chamber 4, the carrier gas carries the aerosol particles to form an aerosol flow, and enters the aerosol beam channel 5 from the aerosol channel 1 through the gas collection chamber 4. The sheath gas surrounds the aerosol flow in the middle to form an aerosol beam flow, which flows through the nozzle 10 and is deposited on the surface of the substrate below. At this time, the vacuum pump and the solenoid valve are both in the closed state, and the two are switched on and off synchronously;

[0079] (2) According to the set parameters, the carrier gas flow rate is adjusted to 50 sccm, the sheath gas flow rate is adjusted to 200 sccm, the height of the nozzle from the substrate is adjusted to 4 mm, and the printing speed is adjusted to 5 mm / s until the printing effect reaches a stable state;

[0080] (3) According to the set printing pattern trajectory requirements, at the position where the aerosol beam flow needs to be cut off, the vacuum pump 12 and the solenoid valve 7 are turned on, and the pressure regulating valve 13 adjusts the gauge pressure to -0.1 kPa. At this time, the aerosol beam flow changes its flow direction when flowing through the aerosol beam flow channel 5, flows out from the cut-off flow channel 6, and after being filtered by the filter 8, the printing material enters the material recovery device 9, and no aerosol beam flow is ejected from the nozzle 10, thereby realizing the cut-off of aerosol printing;

[0081] (4) According to the set printing pattern trajectory requirements, when it is necessary to start aerosol printing, the solenoid valve 7 is closed, and the aerosol beam flows through the nozzle 10 along the aerosol beam channel 5 again, and is deposited on the substrate 11 to start pattern printing, and the aerosol printing process is restarted;

[0082] (5) Repeat the above steps (3) and (4) to achieve high-precision preparation of the set pattern.

[0083] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the present application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0084] In addition, references throughout this specification to "one embodiment"; "one embodiment", "an example" or similar language indicate that a particular feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present application. Thus, appearances of the phrase "in one embodiment"; "in one embodiment" and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0085] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. An aerosol printing device with quick cut-off, characterized in that: The invention comprises a print head unit and a vacuum cut-off unit, wherein: the print head unit comprises an aerosol beam channel (5), an aerosol channel (1) and a sheath gas channel (3) connected to the inlet of the aerosol beam channel (5), and a nozzle (10) connected to the outlet of the aerosol beam channel (5); the vacuum cut-off unit comprises a cut-off channel (6) and a vacuum pumping component, one side of the cut-off channel (6) is connected to an external hollow tube (14) arranged beside the outlet of the nozzle (10) or to the aerosol beam channel (5), and the other side is connected to the vacuum pumping component, so that negative pressure is formed under the action of the vacuum pumping component, and the aerosol in the aerosol beam channel (5) is sucked into the cut-off channel (6) to achieve rapid cut-off.

2. The aerosol printing device according to claim 1, characterized in that: The vacuum pump assembly comprises a filter (8), a raw material recovery device (9) and a vacuum pump (12); the filter (8) is arranged between the cut-off channel (6) and the vacuum pump (12), and the filter (8) is connected to the raw material recovery device (9) for delivering the aerosol in the cut-off channel (6) into the raw material recovery device (9) under the suction action of the vacuum pump (12).

3. The aerosol printing device according to claim 2, characterized in that: The vacuum pumping assembly further comprises a solenoid valve (7), which is arranged between the filter (8) and the vacuum pump (12) and is used to control the opening and closing of the channel between the vacuum pump (12) and the filter (8).

4. The aerosol printing device according to claim 3, characterized in that: The vacuum pumping assembly further comprises a pressure regulating valve (13), which is arranged between the solenoid valve (7) and the filter (8) and is used for regulating pressure.

5. The aerosol printing device according to claim 1, characterized in that: When the cut-off channel (6) is connected to the external hollow tube (14), the distance H2 between the lowest horizontal point of the external hollow tube (14) and the lowest horizontal point of the nozzle (10) is less than 5 mm, and the inner diameter D2 of the end of the external hollow tube (14) close to the nozzle (10) is not less than the inner diameter D1 of the nozzle (10).

6. The aerosol printing device according to claim 1, characterized in that: When the cut-off channel (6) is connected to the aerosol beam channel (5), the cut-off channel (6) is a circular pipe, the inner diameter D4 of the cut-off channel (6) is equal to the inner diameter D3 of the aerosol beam channel (5), and the inner diameter D4 of the cut-off channel (6) is greater than the inner diameter D1 of the nozzle (10).

7. The aerosol printing device according to claim 1, characterized in that: When the cut-off channel (6) is connected to the aerosol beam channel (5), the cut-off channel (6) is a non-circular pipe, the height H1 of the cut-off channel (6) is not less than the inner diameter D3 of the aerosol beam channel (5), the width W of the cut-off channel (6) is not greater than the inner diameter D3 of the aerosol beam channel (5), and the width W of the cut-off channel (6) is greater than the inner diameter D1 of the nozzle (10).

8. The rapid cut-off method of an aerosol jet printing device according to any one of claims 1 to 7, characterized in that: Specifically, the printing head unit is started to print, and when it is necessary to switch to the cut-off state, the vacuum pumping component is turned on, thereby forming a negative pressure in the cut-off channel (6) to suck the aerosol in the aerosol beam channel (5) into the cut-off channel (6) to achieve rapid cut-off, and when it is necessary to switch to the printing state, the vacuum pumping component is turned off.

9. The rapid cut-off method according to claim 8, characterized in that: When the vacuum pumping component includes the electromagnetic valve (7), the vacuum pump (12) is in a normally open state, and the opening and closing of the vacuum component is controlled by opening or closing the electromagnetic valve (7); or, the vacuum pump (12) and the electromagnetic valve (7) are opened or closed synchronously to control the opening and closing of the vacuum component.

10. The rapid cut-off method according to claim 8, characterized in that: When the cut-off channel (6) is connected to the aerosol beam channel (5), the negative pressure P generated by the cut-off channel (6) in the cut-off state is N The following conditions need to be met: Wherein, A is the area of ​​the intersection surface between the cutoff channel (6) and the aerosol beam channel (5), g is the gravitational acceleration, m is the mass of the aerosol particles, H1 is the height of the cutoff channel (6), when the cutoff channel (6) is a circular pipe, the inner diameter of the cutoff channel (6) is its height, θ2 is the angle between the cutoff channel (6) and the aerosol beam channel (5), Q is the sum of the sheath gas flow rate and the carrier gas flow rate, D3 is the inner diameter of the aerosol beam channel (5), and D5 is the diameter of the aerosol flow in the aerosol beam channel (5).

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