Spray deposition 3D printing device based on self-excitation electrostatic field driving, working method and application of working method of spray deposition 3D printing device based on self-excitation electrostatic field driving

Abstract

The invention discloses a spray deposition 3D printing device based on self-excitation electrostatic field driven and application of a method on printing superfine silver grids. The limitation of existing material spray deposition 3D printing in the aspects of nozzle materials, substrate materials, printing stability and the like is broken through, only one electrode is arranged a whole system, acopper foil patch is connected with an alternating-current power supply to serve as an extraction electrode and is tightly attached to the shoulder of a glass nozzle in a wound mode, parameters of thecopper foil patch are simulated and optimized through finite elements to provide the optimal electric field focusing effect, an electric field with enough strength can be obtained under the conditionthat the voltage is smaller, the power supply does not make contact with a material, material spraying is completed only by means of electric field force formed by electrostatic induction, the wholeprinting process is not interfered by residual charges, stable printing under the condition of ultrahigh resolution is achieved, when a high-viscosity nano-silver paste is used as a printing material,single-row directional arrangement of nano-silver particles is achieved, a very large height-width ratio is achieved, and the height-width ratio can still reach 0.44 when the line width of a single-layer silver line is 3 microns.

Description

technical field [0001] The present invention relates to the technical field of 3D printing, in particular to a self-excited electrostatic field-driven ejection deposition 3D printing device, working method and application thereof. Background technique [0002] Material jet deposition 3D printing is an additive manufacturing method based on the principle of droplet jetting to selectively deposit forming materials. At present, a variety of material jet deposition 3D printing technologies have been proposed in the world, mainly including inkjet printing, aerosol jetting, polymer jetting, nanoparticle jetting technology, etc. However, these technologies all have certain defects when making silver mesh transparent electrodes. For example, inkjet printing is currently facing the problem of low resolution, and the line width is greater than 20 μm, which cannot meet the requirements for transparent electrodes in many fields such as touch screens and OLEDs. Moreover, the viscosity o...

AI Technical Summary

Problems solved by technology

[0004] Compared with other material jet deposition 3D printing technologies, although electrohydrodynamic jet 3D printing has very significant and prominent advantages in many aspects, there are still many shortcomings and limitations, mainly including: (1) nozzle material is limited, Electrojet printing requires the nozzle to be conductive (as the first electrode), but the inner diameter of the nozzle is still the main factor limiting the resolution of the printing result. When ultra-fine line width (less than 5 microns) is required, glass (insulating) nozzles are required , and the glass nozzle needs to be sprayed with gold, but the glass nozzle is easily blocked or damaged in the experiment, which increases the cost of the experiment and reduces the efficiency; (2) Since the conductive nozzle is directly connected to the power supply, if the printing material has good conductivity (or is metal material), the jet contains a large amount of residual charge, after being deposited on the substrate, the charge will affect the electrostatic field on the surface of the substrate, and produce Coulomb repulsion with the subsequent flying droplets, making it difficult to achieve stable printing at high resolution , especially the insulating substrate, the residual charge will remain on the substrate for a long time; (3) the material of the receiving substrate (substrate) is limited, and the receiving substrate (substrate) is used as the second electrode, which usually requires the substrate to have Conductive, faces limitations when printing on non-conductive substrates, requires some special handling

[0005] The patent (Application No. 201710528176.8) discloses an electric field-driven spray deposition 3D printing device. This method only uses a connected ring-shaped extraction electrode to provide the required electric field, does not require a grounded counter electrode, and the ring electrode does not directly contact the nozzle. It has broken through the limitations of the existing material jet deposition 3D printing in terms of printing materials, nozzle materials, substrate materials, etc., but there are still some problems in use. (1) Although this method requires ensuring that the ring electrode and the nozzle are concentric, however It is difficult to ensure high-precision concentricity in actual use. Therefore, the roundness and concentricity of the two will affect the stability of the electric field during high-precision printing, thereby affecting the accuracy of printing results; (2) The applicant found that because the extraction electrode is a flat electrode, The center is set as a circular through hole, and the wall thickness, that is, the distance between the outer diameter and the central circular hole is relatively large, and the inner diameter of the extraction electrode does not fit the outer wall of the nozzle, resulting in an unsatisfactory electric field focusing effect, and the electric field directly below the nozzle The strength is low, which affects the high and stable electric field requirements for high-precision printing

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