Viscous ink printing method and device

Abstract

The present invention discloses a viscous ink printing method and device, and relates to the technical field of ink printing. The viscous ink printing method is applied to a viscous ink printing device, and the viscous ink printing device includes a nozzle and a first transducer and a second transducer arranged on both sides of the nozzle; the viscous ink printing method includes: obtaining a target area; calculating an operating parameter according to the target area; and adjusting the inkjet force applied by the first transducer and the second transducer to the nozzle according to the operating parameter, so that the volume of the ink droplet is consistent with the target area. The technical solution of the present invention avoids being affected by the environment and air pressure accuracy, thereby improving the volume accuracy of the ink droplet when it is ejected.

Description

Technical Field

[0001] The present invention relates to the technical field of ink printing, and in particular to a viscous ink printing method and device. Background Art

[0002] In conventional printing, it is difficult to eject ink droplets from the nozzle simply by gravity due to the wettability of the microchannel and the capillary force. At this time, external forces such as piezoelectric ceramic pressure or the vertical electric field force in the electrofluid are needed. Inkjet printing uses a piezoelectric ceramic microstructure design, which makes it difficult for the nozzle channel to generate a large extrusion force, and electrofluid printing requires the ink to have conductive properties, making many high-viscosity and non-conductive polymers difficult to apply to these printing technologies.

[0003] High molecular weight and high viscosity liquids play an important role in industrial manufacturing, drug synthesis, biological research and food processing. For high viscosity inks, air pressure and needles are usually used to extrude the liquid, but the inkjet method of the prior art is often affected by the environment and air pressure accuracy, making it difficult to obtain an accurate liquid volume. Summary of the invention

[0004] The main purpose of the present invention is to provide a viscous ink printing method and device, aiming to solve the technical problem in the prior art that inkjet is affected by the environment and air pressure accuracy, making it difficult to obtain an accurate liquid volume.

[0005] To achieve the above object, the present invention provides a viscous ink printing method, which is applied to a viscous ink printing device, wherein the viscous ink printing device comprises a nozzle and a first transducer and a second transducer arranged on both sides of the nozzle; the viscous ink printing method comprises:

[0006] Get the target area;

[0007] calculating operating parameters according to the target area;

[0008] The inkjet force applied by the first transducer and the second transducer to the nozzle is adjusted according to the operating parameter so that the volume of the ink droplet is consistent with the target area.

[0009] In one embodiment, the step of adjusting the inkjet force applied by the first transducer and the second transducer to the nozzle according to the operating parameter comprises:

[0010] adjusting respectively a first complex sound pressure amplitude applied by the first transducer to the nozzle and a second complex sound pressure amplitude applied by the second transducer to the nozzle according to the operating parameters;

[0011] The ink ejection force is calculated according to the first complex sound pressure amplitude and the second complex sound pressure amplitude.

[0012] In one embodiment, the step of calculating the inkjet force according to the first complex sound pressure amplitude and the second complex sound pressure amplitude comprises:

[0013] obtaining the gravity of the ink droplet in the nozzle;

[0014] Calculating the acoustic radiation force exerted on the nozzle by the first transducer and the second transducer according to the first complex sound pressure amplitude and the second complex sound pressure amplitude;

[0015] The inkjet force is calculated according to the gravity and the acoustic radiation force.

[0016] In one embodiment, the first complex sound pressure amplitude, the second complex sound pressure amplitude, and the acoustic radiation force satisfy the following relationship:

[0017] ;

[0018] in, ; F n (r, t) is the acoustic radiation force, I n (r, t) is the sound intensity when the first transducer and the second transducer are in operation, I n,A (r) is the first complex sound pressure amplitude, I n,B (r) is the second complex sound pressure amplitude, is the central angular frequency of the first transducer, is the central angular frequency of the second transducer, t is the time node, r is the position coordinate of the first transducer and / or the second transducer, c is the sound propagation speed, α n is the sound absorption coefficient of the nth harmonic.

[0019] In one embodiment, the step of obtaining the gravity of the ink droplet in the nozzle includes:

[0020] Obtaining the diameter of the nozzle and the density of the ink droplets;

[0021] The gravity is calculated based on the diameter and the density.

[0022] In one embodiment, the gravity, the acoustic radiation force and the inkjet force satisfy the following relationship:

[0023] ;

[0024] but, , , ;

[0025] Among them, F c is the inkjet force, F g is the gravity, F n is the acoustic radiation force, g is the gravitational acceleration, g a is the acceleration of the ink droplet ejected from the nozzle, ρ is the density, δ is the surface tension of the ink droplet, d is the diameter, R is the diameter of the ink droplet, and V is the volume of the ink droplet.

[0026] In one embodiment, the step of calculating the operating parameters according to the target area includes:

[0027] Build mathematical models;

[0028] Detect the current area of ​​the ink drop;

[0029] comparing the current area with the target area;

[0030] Acquire multiple comparison results, and generate a data set according to the multiple comparison results;

[0031] Importing the above data set into the mathematical model to generate a corresponding characteristic function;

[0032] The corresponding operating parameters are calculated according to the characteristic function and the target area.

[0033] In addition, in order to solve the above problems, the present invention also proposes a viscous ink printing device, the viscous ink printing device comprising:

[0034] A housing having a cavity therein;

[0035] A nozzle, the nozzle is arranged in the cavity, and the bottom of the nozzle is tapered to form a nozzle;

[0036] A first transducer and a second transducer, wherein the first transducer and the second transducer are both disposed on the housing and are respectively located on two opposite sides of the nozzle;

[0037] A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the viscous ink printing method as described above.

[0038] In one embodiment, the housing is annular, the number of the first transducers is multiple, and the multiple first transducers are arranged at intervals along the circumferential direction of the side wall of the housing;

[0039] The number of the second transducers is consistent with the number of the first transducers and is arranged in a one-to-one correspondence.

[0040] In one embodiment, the number of the nozzles is multiple, and the multiple nozzles are arranged at intervals; wherein the number of the first transducers and the second transducers are consistent with the number of the nozzles and are arranged in a one-to-one correspondence.

[0041] The technical solution of the present invention uses two different frequencies of acoustic radiation force coupling and irradiation to achieve quasi-harmonic pressure to print high-viscosity ink, that is, through the cooperation of the first transducer and the second transducer, the nonlinear interference effect of the acoustic wave with a certain frequency difference is used to constrain the confocal area, and a modulated sound field is generated in the confocal area to drive the ink droplets to be ejected from the nozzle. Avoid being affected by the environment and air pressure accuracy, thereby improving the volume accuracy of the ink droplets when ejecting. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0043] Figure 1 A schematic flow chart of a first embodiment of a viscous ink printing method provided by the present invention;

[0044] Figure 2 A schematic flow chart of a second embodiment of a viscous ink printing method provided by the present invention;

[0045] Figure 3 A schematic flow chart of a third embodiment of a viscous ink printing method provided by the present invention;

[0046] Figure 4 A schematic flow chart of a fourth embodiment of a viscous ink printing method provided by the present invention;

[0047] Figure 5 A schematic diagram of the structure of the viscous ink printing device provided by the present invention;

[0048] Figure 6 A schematic diagram of the operation of a transducer in a viscous ink printing device provided by the present invention;

[0049] Figure 7 for Figure 5 Dimensional identification diagram for medium viscosity ink printing unit.

[0050] Description of Figure Numbers:

[0051] 10. Shell; 11. Cavity; 20. Nozzle; 21. Nozzle; 31. First transducer; 32. Second transducer; 40. Substrate.

[0052] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0055] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0056] The present invention provides a viscous ink printing method, which is applied to a viscous ink printing device.

[0057] See also Figure 1 In a first embodiment of the present invention, the viscous ink printing method comprises the following steps:

[0058] Step S10: obtaining the target area;

[0059] Step S20: calculating operating parameters according to the target area;

[0060] Step S30: adjusting the inkjet force applied by the first transducer 31 and the second transducer 32 to the nozzle 21 according to the operating parameters, so that the volume of the ink droplet is consistent with the target area.

[0061] See also Figure 5 The viscous ink printing device includes a nozzle 21 and a first transducer 31 and a second transducer 32 arranged on both sides of the nozzle 21 .

[0062] Based on the traditional piezoelectric ceramic extrusion inkjet printing technology, the pressure design usually satisfies the harmonic pressure curve. Therefore, in the high-viscosity inkjet printing process, the present application adjusts the ultrasonic frequency so that the acoustic radiation force generates a quasi-harmonic pressure curve, thereby ensuring that the ink droplet volume and speed remain stable during the printing process.

[0063] In the present invention, the difference frequency ultrasonic printing method requires the use of two different frequencies of acoustic radiation force coupling and irradiation to achieve quasi-harmonic pressure to print high-viscosity ink, that is, the nonlinear interference effect of sound waves with a certain frequency difference constrained in the confocal area is used to generate a modulated sound field in the confocal area.

[0064] In one embodiment, a greater acoustic radiation force can be achieved by increasing the ultrasonic power, such as increasing the ultrasonic sound pressure or sound intensity, irradiation time, etc., so as to eject the high-viscosity ink droplets out of the nozzle 21. However, the ultrasonic sound field has a large radiation range, and in order to avoid the divergence of the radiation force, it should be sufficient to reach the force size for squeezing the ink.

[0065] In another embodiment, the first transducer 31 and the second transducer 32 can be used to print high-viscosity ink by coupling and irradiating two acoustic radiation forces of different frequencies to achieve quasi-harmonic pressure. The nonlinear interference effect of acoustic waves with a certain frequency difference constrained in the confocal area is used to generate a modulated acoustic field in the confocal area. This can further reduce the size of the device and enable the integration of multiple nozzles 21.

[0066] Specifically, the transducer in the present application may be a piezoelectric transducer, which deforms under the action of an electric field through the characteristics of piezoelectric materials. Figure 6 For example, an ultrasonic transducer is formed by using the inverse piezoelectric effect of a piezoelectric crystal. The piezoelectric ceramic is made into a sheet and polarized, and a silver layer is coated on the upper and lower surfaces as electrodes. An electric field is applied between the piezoelectric sheets. The ultrasonic pulse is obtained by switching the electric field direction and the polarization direction at high frequency.

[0067] When the external electric field is in the same direction as the polarization direction, the polarization strength of the piezoelectric film is enhanced by the external electric field. The enhancement of the polarization strength causes the piezoelectric film along the polarization direction to produce tensile deformation; when the external electric field is in the opposite direction to the polarization direction, the polarization strength of the piezoelectric film is reduced by the reverse electric field, causing the piezoelectric film to produce compressive deformation along the polarization direction.

[0068] In this embodiment, please refer to Figure 5The first transducer 31 and the second transducer 32 are respectively arranged on the left and right sides of the nozzle 21. To ensure the accuracy requirement, the first transducer 31 and the second transducer 32 are symmetrically arranged on the left and right sides of the nozzle 21 with the gravity direction as the symmetry axis.

[0069] When inkjet is being performed, the ink is ejected from the nozzle 21 and printed onto the surface of the substrate 40 to be processed to form circular ink drops. First, the target area corresponding to the ink drop is set according to the printing requirements, and the operating parameters corresponding to the first transducer 31 and the second transducer 32 are calculated according to the target area.

[0070] The first transducer 31 and the second transducer 32 are controlled to operate according to the operating parameters, thereby ensuring that ink droplets of the same size as the target area are printed.

[0071] In the design of the difference frequency ultrasonic radiation force field, this embodiment adopts an arc-shaped ultrasonic transducer, which is arranged by a staggered method to achieve a pair of ultrasonic waves or even multiple pairs of ultrasonic waves being emitted simultaneously.

[0072] The technical solution of the present invention realizes quasi-harmonic pressure to print high-viscosity ink by coupling and irradiating two acoustic radiation forces of different frequencies, that is, by cooperating with the first transducer 31 and the second transducer 32, the nonlinear interference effect of acoustic waves with a certain frequency difference constrained in the confocal area is utilized, and a modulated acoustic field is generated in the confocal area to drive ink droplets to be ejected from the nozzle 21. The influence of the environment and air pressure accuracy is avoided, thereby improving the volume accuracy of ink droplets when ejecting.

[0073] See also Figure 2 In the second embodiment of the present invention, step S30 includes:

[0074] Step S31: adjusting the first complex sound pressure amplitude applied by the first transducer 31 to the nozzle 21 and the second complex sound pressure amplitude applied by the second transducer 32 to the nozzle 21 according to the operating parameters;

[0075] Step S32: calculating the inkjet force according to the first complex sound pressure amplitude and the second complex sound pressure amplitude.

[0076] The ink ejection force exerted on the nozzle 21 by the first transducer 31 and the second transducer 32 is mainly composed of the first complex sound pressure amplitude and the second complex sound pressure amplitude.

[0077] The first complex sound pressure amplitude, the second complex sound pressure amplitude and the acoustic radiation force satisfy the following expression:

[0078] Expression 1: ;

[0079] Expression 2: ;

[0080] F n (r, t) is the acoustic radiation force, I n (r, t) is the sound intensity when the first transducer 31 and the second transducer 32 are in operation, I n,A (r) is the first complex sound pressure amplitude, I n,B (r) is the second complex sound pressure amplitude, is the central angular frequency of the first transducer 31, is the central angular frequency of the second transducer 32 , t is the time node for calculating the irradiation time, and r is the position coordinate of the first transducer 31 and / or the second transducer 32 .

[0081] According to Expression 2, at the first transducer 31 at the center angular frequency In operation, the second transducer 32 is at a center angular frequency It can be understood that during the operation of the first transducer 31 and the second transducer 32, the sound field generated in the interference region of the two sound beams includes not only the angular frequency and The sound field also includes Therefore, the sound intensity generated by the first transducer 31 and the second transducer 32 when they are in operation is calculated by Expression 2.

[0082] Since the sound energy of the high-frequency part is not within the low-frequency range, the influence of the high-frequency part on the modulated sound radiation force is removed.

[0083] Substituting the sound intensity into Expression 1, F n (r, t) is the acoustic radiation force, r is the position coordinate of the first transducer 31 and / or the second transducer 32, c is the sound propagation speed, α n is the sound absorption coefficient of the nth harmonic. Among them, the sound absorption coefficient has a power relationship with the frequency: , γ represents the sound absorption index, I n Indicates the sound intensity of the nth harmonic frequency.

[0084] The acoustic radiation forces applied to the nozzle 21 by the first transducer 31 and the second transducer 32 are calculated by Expression 1 and Expression 2.

[0085] During the printing process, under the action of the first transducer 31 and the second transducer 32, the high viscosity ink is made to have a vertical downward ink jet force by using the acoustic radiation force, which provides the effect of squeezing the ink downward. In addition, during the ultrasonic high viscosity printing process, the ink jet force mainly depends on the ultrasonic frequency, sound pressure or sound intensity, short pulse and irradiation time. Therefore, the operating parameters may also include, for example, adjusting parameters such as sound intensity, short pulse and irradiation time.

[0086] See also Figure 3 In the third embodiment of the present invention, step S32 includes:

[0087] Step S321: obtaining the gravity of the ink droplet in the nozzle 21;

[0088] Step S322: calculating the acoustic radiation force exerted by the first transducer 31 and the second transducer 32 on the nozzle 21 according to the first complex sound pressure amplitude and the second complex sound pressure amplitude;

[0089] Step S323: calculating the inkjet force according to the gravity and the acoustic radiation force.

[0090] For nozzles of different shapes and sizes, in order to further improve the area accuracy of printing after the ink droplets are squeezed out, the acoustic radiation force is also calculated in combination with the gravity of the ink droplets in this embodiment.

[0091] It is understandable that due to the different shapes and sizes of the nozzles 21, or even if the nozzles 21 of the same model are limited by their process limitations, their sizes may also be slightly different. Therefore, the gravity of the ink droplets stored in the nozzles 21 can also be calculated at the same time.

[0092] See also Figure 5 The nozzle 21 is gradually set along the gravity direction, and the top is connected to the needle tube. The needle tube needs to use a transducer to realize a vertical downward force according to the nozzle 21.

[0093] As an embodiment, in order to improve the printing efficiency, multiple nozzles 21 are provided to print simultaneously in this embodiment. In order to ensure the same printing effect, the ink jetting force of each nozzle 21 is adjusted independently according to the gravity of the ink droplets in different needle tubes and the corresponding acoustic radiation force, so that after each nozzle 21 prints, the ink droplets can meet the target area requirements. This avoids the problem of the size of the nozzle 21, which causes the ink droplets of different nozzles 21 to form different areas on the substrate 40 after printing.

[0094] When designing the size of the nozzle 21, the ultrasonic focusing height H can be designed according to the area range of the printing ink droplets. h At the same time, due to the falling speed of the ink droplets and the horizontal traveling speed, the spacing height L between the substrate 40 and the nozzle 21 needs to be controlled to obtain the printing spacing Δ.

[0095] For further analysis based on fluid mechanics simulation, please refer to Figure 7 , in order to design the maximum diameter d of the nozzle 21 and the length d of the nozzle 21 h , the minimum diameter d of the nozzle 21 o In this embodiment, d=0.5mm, d h =3mm, L is the half wavelength of ultrasound, do Design is carried out with = 50um as an example.

[0096] Specifically, step S321 includes:

[0097] Step S324: Obtain the diameter of the nozzle 21 and the density of the ink droplet;

[0098] Step S325: Calculate the gravity according to the diameter and the density.

[0099] The diameter d of the nozzle 21 is obtained by measurement, and the density ρ of the ink droplet is detected. The gravity, the acoustic radiation force, and the inkjet force satisfy the following expression:

[0100] Expression 3: ;

[0101] According to Expression 3, it can be deduced that , , .

[0102] Among them, F c is the inkjet force, F g is the gravity, F n is the acoustic radiation force, g is the acceleration due to gravity, g a is the acceleration of the ink droplet ejected from the nozzle 21, ρ is the density, δ is the surface tension of the ink droplet, d is the diameter, R is the diameter of the ink droplet, and V is the volume of the ink droplet.

[0103] By calculating the gravity F of the ink droplet in the nozzle 21 g , and combining it with the acoustic radiation force F applied to the nozzle 20 n to obtain a downward resultant force, that is, the inkjet force F c , where F c should be greater than the resistance F of the ink in the nozzle 20 f to enable the ejection of high-viscosity ink.

[0104] For high-viscosity ink, its Ohnesorge number: ; For traditional printers, the Z value of its low-viscosity ink is usually in a relatively small range, such as 0.1 < Z < 1, while for high-viscosity ink such as UV glue, the Z value is usually between 10 and 100. Therefore, in this embodiment, the operating parameters can also be adjusted according to the viscosity of different inks to ensure that the ink can be smoothly ejected from the nozzle 21.

[0105] Please refer to Figure 4 , in the fourth embodiment of the present invention, step S20 includes:

[0106] Step S21: Establish a mathematical model;

[0107] Step S22: detecting the current area of ​​the ink droplet;

[0108] Step S23: comparing the current area with the target area;

[0109] Step S24: obtaining a plurality of comparison results, and generating a data set according to the plurality of comparison results;

[0110] Step S25: importing the above data set into the mathematical model to generate a corresponding characteristic function;

[0111] Step S26: Calculate the corresponding operating parameters according to the characteristic function and the target area.

[0112] In order to improve the degree of automation, the first transducer 31 and the second transducer 32 are debugged before they are put into operation.

[0113] By establishing a mathematical model, in this embodiment, the "random forest" mathematical model is taken as an example, the target area required for printing and the moving speed of the nozzle are imported, and the nozzle 21 is controlled to print. During the printing process, the ink droplets are photographed by a high-speed camera, and the contour and position of the ink droplets are obtained by image analysis, and the current area of ​​the ink droplets after printing is calculated. After comparing the current area with the target area, the target area required for importing printing and the moving speed of the nozzle are adjusted. After repeating the above steps, multiple comparison results can be obtained, and the Canny algorithm is used for calculation to obtain the eigenvalue and characteristic function.

[0114] After debugging, the target area and moving speed are imported, and the corresponding operating parameters can be obtained through the mathematical model. When there are multiple nozzles 21, the ultrasonic waveforms of the first transducer 31 and the second transducer 32 corresponding to each nozzle 21 are synchronized by FPGA to achieve high-frequency printing.

[0115] The present invention also provides a viscous ink printing device, which includes a housing 10, a nozzle 20, a first transducer 31 and a second transducer 32. The housing 10 has a cavity 11 therein; the nozzle 20 is disposed in the cavity 11, and the bottom of the nozzle 20 is tapered to form a nozzle 21; the first transducer 31 and the second transducer 32 are both disposed on the housing 10 and are respectively located on opposite sides of the nozzle 21. A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the viscous ink printing method as described above.

[0116] The specific structure of the viscous ink printing method refers to the above embodiments. Since the viscous ink printing device adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.

[0117] The shell 10 is annular, and the number of the first transducers 31 is multiple, and the multiple first transducers 31 are arranged at intervals along the circumferential direction of the side wall of the shell 10; the number of the second transducers 32 is consistent with the number of the first transducers 31 and is arranged one-to-one.

[0118] See also Figure 5 The housing 10 is annular and has a circular cavity 11 in the center. The first transducer 31 and the second transducer 32 are arc-shaped ultrasonic transducers. Each first transducer 31 and a second transducer 32 form a group, and a group or even multiple groups of ultrasonic emission are realized by the staggered method, thereby improving the sound radiation force.

[0119] There are multiple nozzles 21 , and the multiple nozzles 21 are arranged at intervals; wherein the number of the first transducers 31 and the second transducers 32 are consistent with the number of the nozzles 21 and are arranged in a one-to-one correspondence.

[0120] In order to improve the printing efficiency, multiple nozzles 21 are set at the same time, and the ultrasonic waveforms of the first transducer 31 and the second transducer 32 corresponding to each nozzle 21 are synchronized by FPGA to achieve high-frequency printing.

[0121] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A viscous ink printing method, characterized in that: The viscous ink printing method is applied to a viscous ink printing device, wherein the viscous ink printing device comprises a nozzle and a first transducer and a second transducer arranged on both sides of the nozzle; The viscous ink printing method comprises: Get the target area; calculating operating parameters according to the target area; adjusting respectively a first complex sound pressure amplitude applied by the first transducer to the nozzle and a second complex sound pressure amplitude applied by the second transducer to the nozzle according to the operating parameters; obtaining the gravity of the ink droplet in the nozzle; Calculating the acoustic radiation force exerted on the nozzle by the first transducer and the second transducer according to the first complex sound pressure amplitude and the second complex sound pressure amplitude; Calculating inkjet force according to the gravity and the acoustic radiation force so that the volume of the ink droplet is consistent with the target area; The first complex sound pressure amplitude, the second complex sound pressure amplitude and the acoustic radiation force satisfy the following relationship: ； in, ; F n (r, t) is the acoustic radiation force, I n (r, t) is the sound intensity when the first transducer and the second transducer are in operation, I n,A (r) is the first complex sound pressure amplitude, I n,B (r) is the second complex sound pressure amplitude, is the central angular frequency of the first transducer, is the central angular frequency of the second transducer, t is the time node, r is the position coordinate of the first transducer and / or the second transducer, c is the sound propagation speed, α n is the sound absorption coefficient of the nth harmonic.

2. The viscous ink printing method according to claim 1, characterized in that: The step of obtaining the gravity of the ink droplet in the nozzle comprises: Obtaining the diameter of the nozzle and the density of the ink droplets; The gravity is calculated based on the diameter and the density.

3. The viscous ink printing method according to claim 2, characterized in that: The gravity, the acoustic radiation force and the inkjet force satisfy the following relationship: ； but, , ; Among them, F c is the inkjet force, F g is the gravity, F n is the acoustic radiation force, g is the gravitational acceleration, g a is the acceleration of the ink droplet ejected from the nozzle, ρ is the density, δ is the surface tension of the ink droplet, d is the diameter, R is the diameter of the ink droplet, and V is the volume of the ink droplet.

4. The viscous ink printing method according to claim 1, characterized in that: The step of calculating the operating parameters according to the target area comprises: Build mathematical models; Detect the current area of ​​the ink drop; comparing the current area with the target area; Acquire multiple comparison results, and generate a data set according to the multiple comparison results; Importing the above data set into the mathematical model to generate a corresponding characteristic function; The corresponding operating parameters are calculated according to the characteristic function and the target area.

5. A viscous ink printing device, characterized in that: The viscous ink printing device comprises: A housing having a cavity therein; A nozzle, the nozzle is arranged in the cavity, and the bottom of the nozzle is tapered to form a nozzle; A first transducer and a second transducer, wherein the first transducer and the second transducer are both disposed on the housing and are respectively located on two opposite sides of the nozzle; A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the viscous ink printing method according to any one of claims 1 to 4.

6. The viscous ink printing device according to claim 5, characterized in that: The housing is annular, the number of the first transducers is multiple, and the multiple first transducers are arranged at intervals along the circumferential direction of the side wall of the housing; The number of the second transducers is consistent with the number of the first transducers and is arranged in a one-to-one correspondence.

7. The viscous ink printing device according to claim 5, characterized in that: The number of the nozzles is multiple, and the multiple nozzles are arranged at intervals; wherein the number of the first transducers and the second transducers are consistent with the number of the nozzles and are arranged in a one-to-one correspondence.

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