Processing technology of electrofluid spray head with controllable printing height and electrofluid spray head

Abstract

The invention relates to a processing technology of an electrofluid spray head with a controllable printing height and the electrofluid spray head. The processing technology comprises the following steps: processing a spray hole and a wiring hole in the bottom surface of a glass substrate; a sinking ring groove is formed in the bottom surface of the glass substrate to form a jet boss; forming a seed layer on the glass substrate, and dividing the seed layer into an electroplating area and a non-electroplating area; forming a first conductive layer in the electroplating area to form a conductive ring; a second conducting layer is formed in a patterning mode, electrode rings of the second conducting layer surround the outer side of the spraying boss, and the electrode rings are electrically connected with the bottoms of the multiple conducting rings through leads of the second conducting layer; and covering a protective layer on the surface of the second conductive layer. According to the electrofluid sprayer formed through the machining technology, the electrode ring on the outer side of the spraying boss is not prone to being polluted, the flexible circuit board can be connected to the top face of the glass substrate by machining the wiring hole and the conducting ring, the occupied structure of the bottom face of the glass substrate is removed, interference on printing height adjustment can be removed, and the printing efficiency is improved. And normal operation of printing processing is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of inkjet printing, and in particular to a processing technology of an electrofluidic nozzle with controllable printing height and an electrofluidic nozzle. Background Art

[0002] As a direct writing technology for additive manufacturing, inkjet printing has the advantages of no need for masks, flexible production, and high material utilization. It has good application prospects in the fields of printed displays, printed circuits, and printed solar cells. Among them, electrofluidic inkjet printing technology uses electric field force as the main driving force, which greatly enhances the driving ability of ink and can print high-viscosity ink; at the same time, because the injection occurs locally on the curved liquid surface, the size of the ink droplets produced can be much smaller than the nozzle diameter, which can significantly improve the printing resolution. Electrofluidic inkjet printing technology overcomes the two major shortcomings of traditional inkjet printing technology and has broad application prospects.

[0003] In the related art, in order to achieve independent control of multiple nozzles of a nozzle, generally, electrode rings are arranged for the multiple nozzles on the injection surface of the nozzle. The electrode rings are located at the nozzles. By separately controlling each electrode ring, the multiple nozzles can be independently controlled, thereby achieving work requirements such as shielding of defective nozzles and complex pattern printing.

[0004] However, when the electrode ring is arranged on the injection surface, on the one hand, when the functional liquid at the nozzle hole forms a Taylor cone, it may adhere to the electrode ring, corrode the electrode ring and affect the electric field at the nozzle hole, causing the nozzle hole to fail. On the other hand, when the external flexible circuit board is electrically connected to multiple electrode rings, one end of the flexible circuit board needs to be fixed and packaged on the injection surface of the nozzle. Due to the flexible circuit board on the injection surface of the nozzle, the printing height between the injection surface of the nozzle and the substrate is limited during the printing process, which interferes with the printing process and affects the normal printing process. Summary of the invention

[0005] The embodiment of the present application provides a processing technology and an electrofluidic nozzle with controllable printing height to solve the technical problems in the related art that the functional liquid easily corrodes and damages the electrode ring, and the packaging position of the circuit board interferes with the printing process, affecting the normal printing process.

[0006] In a first aspect, a process for printing a highly controllable electrofluidic nozzle is provided, comprising the following steps:

[0007] obtaining a glass substrate;

[0008] Processing array nozzles and wiring holes corresponding to each nozzle on the bottom surface of the glass substrate;

[0009] On the bottom surface of the glass substrate, a sinking annular groove is provided around each spray hole to form a plurality of spray bosses;

[0010] Forming a seed layer on a glass substrate, the seed layer being attached to the surface of the glass substrate and the walls of all nozzle holes and all wiring holes, dividing the seed layer to form electroplating areas and non-electroplating areas on both the top and bottom surfaces of the glass substrate, all nozzle holes being located in the non-electroplating areas, and all wiring holes being located in the electroplating areas;

[0011] Forming a first conductive layer in the electroplating area, removing excess first conductive layer, and retaining the first conductive layer on the inner wall of the wiring hole and around the opening of the wiring hole to form a conductive ring;

[0012] Patterning a second conductive layer, the second conductive layer includes a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the outer sides of the plurality of injection bosses, the plurality of leads respectively electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings, and the tops of the plurality of conductive rings are connected to an external flexible circuit board;

[0013] Covering the surface of the second conductive layer with a protective layer;

[0014] Complete the processing of the injection plate of the electrofluid nozzle.

[0015] In some embodiments, a sinking annular groove is provided around each spray hole to form a plurality of spray bosses, including:

[0016] Laser etching to form the sunken ring groove;

[0017] The groove wall of the sinking ring groove is modified by CNC machining so that the groove wall slope of the sinking ring groove is 50-80 degrees.

[0018] In some embodiments, the height of the injection boss is not greater than the depth of the sinking ring groove, and the height of the injection boss ranges from 50 to 150 microns.

[0019] In some embodiments, the diameter of the injection end surface of the injection boss is 2-5 times the diameter of the injection hole.

[0020] In some embodiments, the step of dividing the seed layer to form electroplating areas and non-electroplating areas on both the top and bottom surfaces of the glass substrate includes:

[0021] On the top and bottom surfaces of the glass substrate, the orthographic projection of the outer frame edge line of the sunken annular groove is used as the projection line. According to the projection lines of all the sunken annular grooves, a partition frame is preset on the top and bottom surfaces of the glass substrate, and all the projection lines on one side of the glass substrate are located within the partition frame.

[0022] The minimum spacing between each projection line and the partition frame is set to the preset spacing spacing, thereby determining the position of each frame line of the partition frame;

[0023] According to the position of the partition frame, the seed layer at the frame line of the partition frame is removed by laser etching to form an electroplating area and a non-electroplating area on both the bottom surface and the top surface of the glass substrate.

[0024] In some embodiments, the patterned second conductive layer includes a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the outer sides of the plurality of injection bosses, and the plurality of leads respectively electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings, including:

[0025] A second conductive layer is formed on the bottom surface of the glass substrate, and an electrode ring of the second conductive layer is arranged around the sinking ring groove.

[0026] In some embodiments, the patterned second conductive layer includes a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the outer sides of the plurality of injection bosses, and the plurality of leads respectively electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings, including:

[0027] The second conductive layer is formed on the bottom surface of the glass substrate and in the groove of the sinking ring groove, the electrode ring of the second conductive layer is formed on the groove bottom of the sinking ring groove, and the lead wire of the second conductive layer is formed on the groove wall of the sinking ring groove and the bottom surface of the glass substrate.

[0028] In some embodiments, after forming the first conductive layer in the electroplating area, removing the excess first conductive layer, retaining the first conductive layer on the inner wall of the wiring hole and around the opening of the wiring hole to form a conductive ring, the method further includes:

[0029] The inkjet printing process is used to fill the wiring holes with conductive material to form conductive columns.

[0030] In some embodiments, a second conductive layer is also formed on the top surface of the glass substrate, and a plurality of electrode rings of the second conductive layer located on the top surface of the glass substrate respectively surround a plurality of nozzles, and a plurality of leads of the second conductive layer located on the top surface of the glass substrate correspond one-to-one to the plurality of electrode rings, one end of the lead is electrically connected to the electrode ring, and the other end of the lead is electrically connected to the external flexible circuit board.

[0031] In some embodiments, the protective layer is covered on the surface of the second conductive layer, including:

[0032] The passivation layer is covered on the surface of the second conductive layer by using a spray glue and metal stripping process;

[0033] A hydrophobic layer is sputtered on the surface of the passivation layer.

[0034] In a second aspect, an electrofluidic nozzle is provided, comprising an ejection plate and an ink cartridge connected to the top surface of the ejection plate; the ejection plate comprises:

[0035] A glass substrate, wherein a plurality of through-spray holes and a plurality of wiring holes are formed on the bottom surface of the glass substrate, and the plurality of wiring holes correspond to the plurality of spray holes one by one; a sinking annular groove is formed on the bottom surface of the glass substrate near the plurality of spray holes to form a plurality of spray bosses at the bottom of the glass substrate;

[0036] A plurality of conductive rings, wherein the plurality of conductive rings are respectively inserted into the plurality of wiring holes, and the top ends of the conductive rings extend to the top surface of the glass substrate, and the bottom ends of the conductive rings extend to the bottom surface of the glass substrate;

[0037] A plurality of electrode rings, each of which surrounds the outer sides of the plurality of injection bosses, and the electrode rings are arranged at the bottom of the sinking ring groove or the bottom surface of the glass substrate;

[0038] A plurality of lead wires, each of which corresponds to each of the plurality of electrode rings, and both ends of each lead wire are electrically connected to the bottom ends of the electrode rings and the conductive rings, respectively; wherein,

[0039] The top ends of the plurality of conductive rings are electrically connected to an external flexible printed circuit board.

[0040] The beneficial effects of the technical solution provided by this application include:

[0041] The embodiment of the present application provides a processing technology for printing an electrofluid nozzle with controllable height, by processing the nozzle hole and the wiring hole on the glass substrate, and processing the sunken ring groove on the bottom surface of the glass substrate to form a spray boss. The electrode ring is formed on the circumferential outer side of the spray boss. When a voltage is applied to the electrode ring and an electric field is applied to spray the functional liquid in the spray hole, the functional liquid forms a Taylor cone on the spray surface of the spray boss. The functional liquid adheres to the spray surface of the spray boss. By processing the spray boss, the position for the functional liquid to form the Taylor cone is reserved. Since the electrode ring is located on the outer side of the spray boss, the functional liquid attached to the spray surface of the spray boss is not easy to contaminate the electrode ring, and the normal operation of the electrode ring is ensured to ensure the normal operation of the corresponding spray hole. Furthermore, since the spray surface of the spray boss is an independent surface, the functional liquid can be attached to the spray surface of the spray boss in a more stable shape to form a Taylor cone with a certain shape to improve the consistency of the spray state of multiple spray holes.

[0042] In addition, by forming a conductive ring in the wiring hole, after the electrode ring is connected to the conductive ring through a lead, the electrode ring can be energized through the conductive ring and the lead above the glass substrate. Therefore, the external flexible circuit board can be electrically connected to multiple conductive rings above the glass substrate. Therefore, the flexible circuit board and its packaging structure no longer occupy the space under the glass substrate to support the glass substrate to be sufficiently close to the substrate to be printed, sufficiently reduce the printing height, and increase the adjustment range of the printing height. The packaging position of the flexible circuit board will not affect the printing height, will not interfere with the printing process, and ensure the normal operation of the printing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 A flow chart of a process for manufacturing an electrofluid nozzle with controllable printing height provided in an embodiment of the present application;

[0045] Figure 2 A schematic diagram of a spray plate of an electrofluidic spray head provided in an embodiment of the present application;

[0046] Figure 3 for Figure 2 A partial schematic diagram of the injection plate of the medium current fluid nozzle;

[0047] Figure 4 A partial schematic diagram of the bottom surface of the injection plate of the electrofluidic nozzle provided in an embodiment of the present application;

[0048] Figure 5 A schematic diagram of a spray plate of an electrofluid spray head provided in another embodiment of the present application;

[0049] Figure 6 for Figure 5 A partial schematic diagram of the injection plate of the medium current fluid nozzle;

[0050] Figure 7 A schematic diagram of a spray plate of an electrofluid spray head provided in another embodiment of the present application;

[0051] Figure 8 for Figure 7 Partial schematic diagram of the injection plate of the medium-current fluid nozzle.

[0052] In the figure: 1, glass substrate; 1a, nozzle; 1b, wiring hole; 1c, sinking ring groove; 11, injection boss; 2, first conductive layer; 3, second conductive layer; 31, electrode ring; 32, lead; 4, protective layer; 41, passivation layer; 42, hydrophobic layer; 5, third conductive layer. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0054] The embodiment of the present application provides a processing technology for an electrofluidic nozzle with controllable printing height and an electrofluidic nozzle. The electrofluidic nozzle formed by the processing technology has an electrode ring on the outside of the injection boss that is not easily contaminated, and by processing wiring holes and conductive rings, a flexible circuit board can be connected to the top surface of the glass substrate, and the occupation structure on the bottom surface of the glass substrate is removed, thereby eliminating interference with the adjustment of the printing height and ensuring normal operation of the printing process. The present application solves the technical problems in the related art that the functional liquid easily corrodes and damages the electrode ring, and the packaging position of the circuit board interferes with the printing process, affecting the normal printing process.

[0055] Reference Figure 1-Figure 3 , a process for printing a highly controllable electrofluidic nozzle, comprising the following steps:

[0056] S100, obtaining a glass substrate 1.

[0057] S200 , processing array nozzle holes 1 a and connection holes 1 b corresponding to each nozzle hole 1 a on the bottom surface of the glass substrate 1 .

[0058] S300 , on the bottom surface of the glass substrate 1 , a sunken annular groove 1 c is provided around each spray hole 1 a to form a plurality of spray bosses 11 .

[0059] S400, forming a seed layer on the glass substrate 1, the seed layer adheres to the surface of the glass substrate 1 and the hole walls of all the nozzle holes 1a and all the wiring holes 1b, and dividing the seed layer to form electroplating areas and non-electroplating areas on the top and bottom surfaces of the glass substrate 1, all the nozzle holes 1a are located in the non-electroplating area, and all the wiring holes 1b are located in the electroplating area.

[0060] S500, forming a first conductive layer 2 in the electroplating area, removing excess first conductive layer 2, retaining the first conductive layer 2 on the inner wall of the wiring hole 1b and around the opening of the wiring hole 1b, and forming a conductive ring.

[0061] S600, patterning the second conductive layer 3, the second conductive layer 3 includes a plurality of electrode rings 31 and a plurality of leads 32, the plurality of electrode rings 31 respectively surround the outer sides of the plurality of injection bosses 11, the plurality of leads 32 respectively electrically connect the plurality of electrode rings 31 with the bottoms of the plurality of conductive rings, and the tops of the plurality of conductive rings are connected to the external flexible circuit board.

[0062] S700 , covering the surface of the second conductive layer 3 with a protective layer 4 .

[0063] S800, completing the processing of the injection plate of the electrofluid nozzle.

[0064] In this way, the injection boss 11 is formed by processing the injection hole 1a and the wiring hole 1b on the glass substrate 1, and processing the sunken annular groove 1c on the bottom surface of the glass substrate 1. The electrode ring 31 is formed on the circumferential outer side of the injection boss 11. When a voltage is applied to the electrode ring 31 and an electric field is applied to spray the functional liquid in the injection hole 1a, the functional liquid forms a Taylor cone on the injection surface of the injection boss 11, and the functional liquid adheres to the injection surface of the injection boss 11. By processing the injection boss 11, a position for the functional liquid to form a Taylor cone is reserved. Since the electrode ring 31 is located on the outer side of the injection boss 11, the functional liquid attached to the injection surface of the injection boss 11 is not easy to contaminate the electrode ring 31, and the normal operation of the electrode ring 31 is guaranteed to ensure the normal operation of the corresponding injection hole 1a. Further, since the injection surface of the injection boss 11 is an independent surface, the functional liquid can be attached to the injection surface of the injection boss 11 in a more stable shape to form a Taylor cone with a certain shape, so as to improve the consistency of the injection state of multiple injection holes 1a.

[0065] In addition, after the electrode ring 31 is connected to the conductive ring through the lead 32 through the conductive ring formed in the wiring hole 1b, the electrode ring 31 can be energized through the conductive ring and the lead 32 above the glass substrate 1. Therefore, the external flexible circuit board can be electrically connected to multiple conductive rings above the glass substrate 1. Therefore, the flexible circuit board and its packaging structure no longer occupy the space below the glass substrate 1, so as to support the glass substrate 1 to be sufficiently close to the substrate to be printed, sufficiently reduce the printing height, and also increase the adjustment range of the printing height. The packaging position of the flexible circuit board will not affect the printing height, will not interfere with the printing process, and ensure the normal operation of the printing process.

[0066] Wherein, in step S100, a glass substrate 1 is obtained.

[0067] In this embodiment, a wafer with a thickness of 200-800 microns is selected as the glass substrate 1 .

[0068] In step S200 , array nozzle holes 1 a and wiring holes 1 b corresponding to each nozzle hole 1 a are processed on the bottom surface of the glass substrate 1 .

[0069] Reference Figure 2-Figure 4 Specifically, the nozzle holes 1a are processed in the middle of the bottom surface of the glass substrate 1 and arranged in multiple rows along the width direction of the glass substrate 1. Multiple nozzle holes 1a in each row are arranged at intervals along the length direction of the glass substrate 1. In this embodiment, the nozzle holes 1a are arranged in two rows. Multiple glass substrates 1 can be spliced ​​into an electrofluid nozzle.

[0070] Furthermore, in this embodiment, the aperture of the nozzle 1a is 15-50 microns. If the aperture of the nozzle 1a is larger than 50 microns, the ejected droplets will be too large, affecting the printing accuracy; if the aperture of the nozzle 1a is too small, the processing will be difficult and the nozzle 1a will be easily blocked.

[0071] Furthermore, the spacing between the nozzle holes 1a is 200-700 microns. By increasing the spacing between the nozzle holes 1a, the electric field crosstalk between the nozzle holes 1a is reduced, thereby ensuring the printing accuracy.

[0072] Specifically, the plurality of wiring holes 1b correspond to the plurality of nozzles 1a one by one, and the plurality of wiring holes 1b are arranged in multiple rows, and the rows of wiring holes 1b are arranged close to the length edge of the glass substrate 1. In this embodiment, the wiring holes 1b are arranged in two rows, and the spacing of the wiring holes 1b is consistent with the contact spacing of the external flexible circuit board.

[0073] Furthermore, in this embodiment, the hole diameter of the wiring hole 1b is 50-150 microns. The preferred hole diameter is 100 microns. Since the depth of the wiring hole 1b is consistent with the thickness of the glass substrate 1, by reducing the ratio of the depth and diameter of the wiring hole 1b, it is convenient to deposit metal in the hole wall later, so as to reduce the difficulty of forming the conductive ring.

[0074] In this embodiment, both the spray hole 1a and the wiring hole 1b are processed into through holes by laser etching process.

[0075] Specifically, laser processing is used to process marking points, nozzle holes 1a and wiring holes 1b on the surface of the glass substrate 1. The positions of the nozzle holes 1a and wiring holes 1b can be determined later by capturing the marking points. Laser-induced etching of the nozzle holes 1a and wiring holes 1b is required during the processing to first form the structural features on the glass substrate 1, so as to avoid damage to the layer structure on the surface of the glass substrate 1 caused by subsequent laser processing.

[0076] In step S300 , a sunken annular groove 1 c is formed around each spray hole 1 a on the bottom surface of the glass substrate 1 to form a plurality of spray bosses 11 .

[0077] Specifically, the height of the injection boss 11 is not greater than the depth of the sinking annular groove 1c, and the height range of the injection boss 11 includes 50-150 microns. By arranging the injection boss 11, and leaving a height difference between the injection surface of the injection boss 11 and the bottom of the sinking annular groove 1c, it is ensured that the functional liquid adheres to the injection surface of the injection boss 11 to form a Taylor cone, the functional liquid is not easy to spread to the bottom of the sinking annular groove 1c, and the functional liquid is not easy to accumulate and adhere to the circumferential outer side of the injection boss 11, so as to keep the injection surface of the injection boss 11 in a clean state, and it is not easy to affect the subsequent Taylor cone forming, thereby ensuring the injection accuracy of the corresponding nozzle 1a. When the height of the injection boss 11 is too high, it affects the direction of the droplets sprayed by the adjacent injection boss 11, affecting the printing uniformity.

[0078] Specifically, step S300 includes steps S310 and S320.

[0079] S310, laser etching to form a sunken annular groove 1c.

[0080] S320, modifying the groove wall of the sinking annular groove 1c by numerical control machining so that the groove wall slope of the sinking annular groove 1c is between 50 and 80 degrees.

[0081] In this way, the sinking ring groove 1c is processed by laser etching, which has low cost and high processing efficiency. However, the verticality of the groove wall of the sinking ring groove 1c formed by laser etching is relatively high, and it is difficult to deposit the conductive layer later. After the groove wall of the sinking ring groove 1c is modified by CNC machining, the slope of the groove wall of the sinking ring groove 1c is adjusted. When the slope of the sinking ring groove 1c is 50-80 degrees, when the conductive layer is subsequently deposited on the groove wall, the deposited conductive layer is not easy to delaminate, curl or even fall off, thereby improving the molding quality.

[0082] In this embodiment, the spray hole 1a, the wiring hole 1b and the sinking annular groove 1c can be processed together to improve the processing efficiency.

[0083] Furthermore, after the sunken annular groove 1c is processed, the diameter of the injection end surface of the injection boss 11 is 2-5 times the diameter of the injection hole 1a.

[0084] By configuring in this way, the diameter of the ejection surface of the ejection boss 11 is designed correspondingly to the aperture of the ejection hole 1a, so that a stable Taylor cone can be formed and a small volume of droplets can be printed. In this embodiment, printing of droplets less than 1 picoliter can be achieved.

[0085] In which, in step S400, a seed layer is formed on the glass substrate 1, the seed layer is attached to the surface of the glass substrate 1 and the hole walls of all the nozzle holes 1a and all the wiring holes 1b, and the seed layer is divided to form electroplating areas and non-electroplating areas on the top and bottom surfaces of the glass substrate 1, all the nozzle holes 1a are located in the non-electroplating areas, and all the wiring holes 1b are located in the electroplating areas.

[0086] Specifically, a seed layer is deposited on the surface of the glass substrate 1 by PVD (physical vapor deposition), and the hole walls of the nozzle 1a and the wiring hole 1b are both deposited with the seed layer. The seed layer is deposited to facilitate the subsequent formation of a conductive layer on the glass substrate 1.

[0087] The seed layer is deposited in this way to make the surface of the glass substrate 1 conductive, so that the entire glass substrate 1 becomes an electrode when the conductive layer is subsequently electroplated to complete the electroplating process.

[0088] In this embodiment, the thickness of the seed layer is 50-500 nanometers, and the material of the seed layer is copper.

[0089] Furthermore, the seed layer is divided to form electroplating areas and non-electroplating areas on the top and bottom surfaces of the glass substrate 1, all the nozzle holes 1a are located in the non-electroplating area, and all the wiring holes 1b are located in the electroplating area.

[0090] The orthographic projection of the outer frame edge of the sunken annular groove 1c is used as the projection line on the top and bottom surfaces of the glass substrate 1. According to the projection lines of all the sunken annular grooves 1c, a partition frame is preset on the top and bottom surfaces of the glass substrate 1, and all the projection lines on one side of the glass substrate 1 are located within the partition frame.

[0091] The minimum spacing between each projection line and the partition frame is set to a preset spacing spacing, thereby determining the position of each frame line of the partition frame. In this embodiment, the spacing spacing includes 50-150 microns.

[0092] According to the position of the separation frame, the seed layer at the frame line of the separation frame is removed by laser etching to form an electroplating area and a non-electroplating area on both the bottom surface and the top surface of the glass substrate 1 .

[0093] In this way, the seed layer on the glass substrate 1 is separated to form independent electroplating areas and non-electroplating areas. When the first conductive layer 2 is subsequently electroplated, the first conductive layer 2 is formed only in the electroplating area. On the one hand, the electroplating area of ​​the first conductive layer 2 is reduced, and the workload of removing the excess first conductive layer 2 is reduced, saving costs. On the other hand, since the injection boss 11 is located in the non-electroplating area, the hole wall of the spray hole 1a and the injection surface of the injection boss 11 will not be electroplated with the first conductive layer 2, thereby protecting the spray hole 1a. The first conductive layer 2 will not be formed inside the spray hole 1a, and the spray hole 1a is not easy to be blocked, and it is not easy for the functional liquid to corrode the inner wall of the spray hole 1a and make the spray hole 1a unusable.

[0094] The structural size and uniformity of the nozzle hole 1a are important parameters for nozzle processing. Therefore, it is necessary to protect the inside of the nozzle hole 1a from being electroplated with other metals. The seed layer is interrupted by laser processing, and the subsequent electroplating process is used to produce an insulating effect at the nozzle hole.

[0095] In step S500, a first conductive layer 2 is formed in the electroplating area, and excess first conductive layer 2 is removed to retain the first conductive layer 2 on the inner wall of the wiring hole 1b and around the opening of the wiring hole 1b to form a conductive ring.

[0096] Specifically, the first conductive layer 2 is formed in the electroplating area of ​​the glass substrate 1 by electroplating process, so that the first conductive layer 2 is formed in the wiring hole 1b. At this time, since the injection boss 11 is in the non-electroplating area, the first conductive layer 2 will not be formed at the injection boss 11.

[0097] Wet etching and photolithography are sequentially performed on the top and bottom surfaces of the glass substrate 1 to remove the redundant first conductive layer 2, while retaining the first conductive layer 2 on the inner wall of the wiring hole 1b and around the opening of the wiring hole 1b, and the retained first conductive layer 2 forms a conductive ring. The top and bottom ends of the conductive ring both have flanges to facilitate electrical connection with other structures. It can be understood that the top end surface of the conductive ring is located on the top surface of the glass substrate 1, and the bottom end surface of the conductive ring is located on the bottom surface of the glass substrate 1.

[0098] Specifically, the material of the first conductive layer 2 includes one of copper, aluminum, gold and silver. In this embodiment, preferably, the material of the first conductive layer 2 includes copper. Further, the thickness of the first conductive layer 2 is 10-50 microns. The thicker the first conductive layer 2 is, the better the stability of the conductive ring after being energized.

[0099] Among them, S600, patterning the second conductive layer 3, the second conductive layer 3 includes multiple electrode rings 31 and multiple leads 32, the multiple electrode rings 31 respectively surround the outer sides of multiple injection bosses 11, the multiple leads 32 respectively electrically connect the multiple electrode rings 31 with the bottom of the multiple conductive rings, and the tops of the multiple conductive rings are connected to the external flexible circuit board.

[0100] Specifically, in this embodiment, the second conductive layer 3 is formed by photolithography using a metal lift-off process. The material of the second conductive layer 3 includes one or more of gold, silver, copper, aluminum, and chromium. In this embodiment, the second conductive layer 3 includes a laminated structure of chromium and gold. Specifically, a chromium layer is first sputtered, and then a gold layer is sputtered on the surface of the chromium layer. In this embodiment, the thickness of the chromium layer is 3-10 nanometers, and the thickness of the gold layer is 200-500 nanometers.

[0101] Reference Figure 5 and Figure 6 Specifically, the second conductive layer 3 is formed on the bottom surface of the glass substrate 1, and the electrode ring 31 is arranged around the sinking ring groove 1c. In this embodiment, the center lines of the electrode ring 31, the sinking ring groove 1c, the injection boss 11 and the injection hole 1a are collinear. The lead wire 32 electrically connects the electrode ring 31 and the wire ring.

[0102] Further, the jetting surface of the jetting boss 11 is higher than or flush with the bottom surface of the glass substrate 1, and the electrode ring 31 is located below the jetting boss 11, forming a bottom-mounted electrode structure. Preferably, the jetting surface of the jetting boss 11 is higher than the bottom surface of the glass substrate 1, that is, the jetting boss 11 is inside the sinking ring groove 1c. At this time, the depth of the sinking ring groove 1c and the height of the jetting boss 11 can be easily controlled. It also prevents the Taylor cone formed by the jetting surface of the jetting boss 11 from being attracted or contaminating the electrode ring 31 at the edge of the sinking ring groove 1c due to external factors.

[0103] Reference Figure 2 and Figure 3 In some embodiments, a second conductive layer 3 is formed on the bottom surface of the glass substrate 1 and in the groove of the sinking ring groove 1c, an electrode ring 31 of the second conductive layer 3 is formed at the bottom of the sinking ring groove 1c, and a lead 32 of the second conductive layer 3 is formed on the groove wall of the sinking ring groove 1c and the bottom surface of the glass substrate 1.

[0104] Furthermore, the electrode ring 31 is arranged near the middle of the bottom surface of the sinking ring groove 1c, and a clearance gap is reserved between the electrode ring 31 and the inner ring edge and the outer ring edge of the bottom of the sinking ring groove 1c. In this embodiment, the clearance gap is 20-100 microns.

[0105] This arrangement prevents the electrode ring 31 from being too close to the bottom edge of the sinking ring groove 1c. When the electrode ring 31 is formed using a metal stripping process, it prevents excessive deposition of photoresist at the corners of the sinking ring groove 1c, which would affect the exposure effect. It ensures that the groove wall of the sinking ring groove 1c does not have an adverse effect on the second conductive layer 3, thereby ensuring that the second conductive layer 3 is stably formed.

[0106] The lead wire 32 of the second conductive layer 3 is formed on the groove wall of the sinking ring groove 1c and the bottom surface of the glass substrate 1, and is electrically connected to the conductive ring by the electrode ring 31. In this embodiment, the groove wall of the sinking ring groove 1c has a certain slope, which reduces the difficulty of forming the second conductive layer 3 on the groove wall of the sinking ring groove 1c, and the formed second conductive layer 3 is more stable and not easy to fall off.

[0107] In this embodiment, the ejection surface of the ejection boss 11 is flush with the bottom surface of the glass substrate 1, or the ejection surface of the ejection boss 11 is higher than the bottom surface of the glass substrate 1. Preferably, the ejection surface of the ejection boss 11 is flush with the bottom surface of the glass substrate 1, and an upper electrode structure is formed at this time. In this way, not only can the ejection boss 11 be formed by machining the sinking ring groove 1c, but also the ejection boss 11 does not need to be machined to adjust its height, thus saving machining costs; in addition, the ejection surface of the ejection boss 11 can be adjusted to be closer to the desired printing substrate, and the printing height adjustment range is larger.

[0108] Wherein, after forming the first conductive layer 2 in the electroplating area in step S500, removing the excess first conductive layer 2, retaining the first conductive layer 2 on the inner wall of the wiring hole 1b and around the opening of the wiring hole 1b, and forming a conductive ring, the method further includes:

[0109] The conductive material is filled into the wiring hole 1b by inkjet printing process to form a conductive column.

[0110] In this embodiment, electrofluid inkjet printing technology is used to fill the wiring hole 1b with a conductive material to form a conductive column in the wiring hole 1b. The conductive material includes one of gold, silver, copper and aluminum.

[0111] In this arrangement, when the external flexible circuit board is connected to the conductive ring on the top surface of the glass substrate 1 , the conductive pillar strengthens the electrical connection stability between the conductive ring and the second conductive layer 3 , making the power supply to the second conductive layer 3 more stable.

[0112] Reference Figure 2 and Figure 3 Further, a third conductive layer 5 is processed on the top surface of the glass substrate 1, and the third conductive layer 5 includes a plurality of connecting wires, which are respectively connected to the plurality of conductive rings, and the external flexible circuit board is connected to the conductive rings by being electrically connected to the connecting wires.

[0113] With this arrangement, the third conductive layer 5 increases the area of ​​electrical connection between the conductive ring and the flexible circuit board, improves the connection stability of the connection at the flexible circuit board, and makes the connection position between the conductive ring and the flexible electrical connection more flexible.

[0114] Specifically, the material of the third conductive layer 5 includes one or more of gold, silver, copper, aluminum and chromium. In this embodiment, the third conductive layer 5 is a laminated structure of a chromium layer and a gold layer. Among them, chromium and gold are sputtered onto the top surface of the glass substrate 1 in sequence, and then the formed chromium layer and gold layer are patterned by a metal stripping process, and the required parts are retained to form a connecting line. The formed thickness of the third conductive layer 5 is consistent with that of the second conductive layer 3, and will not be repeated here.

[0115] Wherein, step S700, covering the surface of the second conductive layer 3 with a protective layer 4, comprises:

[0116] The passivation layer 41 is covered on the surface of the second conductive layer 3 by using a spraying and metal stripping process.

[0117] The hydrophobic layer 42 is formed on the surface of the passivation layer 41 by sputtering.

[0118] Specifically, the material of the passivation layer 41 is silicon dioxide, and the passivation layer 41 is patterned on the surface of the second conductive layer 3 by using a spraying and metal stripping process to protect the second conductive layer 3. In this embodiment, the passivation layer 41 only covers the surface of the electrode ring 31 of the second conductive layer 3 to reduce the processing difficulty and processing cost. The thickness of the passivation layer 41 is 300-600 nanometers.

[0119] Since the glass substrate 1 is provided with a plurality of nozzle holes 1a, and the spacing between the nozzle holes 1a is small, the electrode rings 31 at the periphery of adjacent nozzle holes 1a are prone to electrical crosstalk when a DC pulse is passed through. Depositing the passivation layer 41 can prevent the generation of electrical crosstalk, oxidation of the electrode rings 31, and short circuit caused by ink droplet splashing.

[0120] The hydrophobic layer 42 is made of parylene and is coated on the bottom surface of the glass substrate 1 by sputtering or vapor deposition to cover the structure of the bottom surface of the glass substrate 1 and the passivation layer 41 to protect the second conductive layer 3. The thickness of the hydrophobic layer 42 is 300-1000 nanometers.

[0121] The hydrophobic layer 42 can adjust the hydrophilic and hydrophobic properties at the nozzle hole 1 a , and has the functions of anti-oxidation and static discharge, while not affecting the wire bonding process on the top surface of the glass substrate 1 .

[0122] Some embodiments, before step S800, further include:

[0123] Reference Figure 7 and Figure 8 A second conductive layer 3 is also formed on the top surface of the glass substrate 1. A plurality of electrode rings 31 of the second conductive layer 3 located on the top surface of the glass substrate 1 surround the plurality of nozzles 1a respectively. A plurality of leads 32 of the second conductive layer 3 located on the top surface of the glass substrate 1 correspond one to one to the plurality of electrode rings 31. One end of the lead 32 is electrically connected to the electrode ring 31, and the other end of the lead 32 is electrically connected to the external flexible circuit board.

[0124] In this arrangement, each nozzle 1a corresponds to two electrode rings 31, wherein the upper electrode ring 31 applies high voltage to the functional liquid in the nozzle 1a, so that the functional liquid in the nozzle 1a is in a critical state of injection. The lower electrode ring 31 applies a bias voltage to the functional liquid in the nozzle 1a, so that the functional liquid in the nozzle 1a breaks through the critical state of injection and is ejected. By arranging two electrode rings 31, the voltage at the two electrode rings 31 of each nozzle 1a can be adjusted using a flexible circuit board, so that the integration of the electrofluid nozzle is higher.

[0125] Specifically, the molding process of the second conductive layer 3 on the top surface of the glass substrate 1 is consistent with the molding process of the second conductive layer 3 on the bottom surface of the glass substrate 1 , which will not be described in detail herein.

[0126] After forming the second conductive layer 3 on the top surface of the glass substrate 1 , it is necessary to process a protective layer 4 on the conductive layer on the top surface of the glass substrate 1 .

[0127] Wherein, in step S800, the processing of the injection plate of the electrofluidic nozzle is completed.

[0128] Specifically, through steps S100 to S700, the glass substrate 1 is processed into a spray plate of the electrofluidic nozzle, and then the ink cartridge structure is installed on the top surface of the glass substrate 1 to assemble the electrofluidic nozzle.

[0129] The embodiment of the present application provides a process for processing an electrofluid nozzle with controllable printing height, wherein the spray boss 11 is formed by processing the spray hole 1a and the wiring hole 1b on the glass substrate 1, and processing the sunken annular groove 1c on the bottom surface of the glass substrate 1. The electrode ring 31 is formed on the circumferential outer side of the spray boss 11. When a voltage is applied to the electrode ring 31 and an electric field is applied to spray the functional liquid in the spray hole 1a, the functional liquid forms a Taylor cone on the spray surface of the spray boss 11, and the functional liquid adheres to the spray surface of the spray boss 11. By processing the spray boss 11, a position for the functional liquid to form a Taylor cone is reserved. Since the electrode ring 31 is located on the outer side of the spray boss 11, the functional liquid attached to the spray surface of the spray boss 11 is not easy to contaminate the electrode ring 31, and the normal operation of the electrode ring 31 is ensured, so as to ensure the normal operation of the corresponding spray hole 1a. Furthermore, since the ejection surface of the ejection boss 11 is an independent surface, the functional liquid can be attached to the ejection surface of the ejection boss 11 in a more stable shape to form a Taylor cone with a certain shape, so as to improve the consistency of the ejection state of the multiple ejection holes 1a.

[0130] In addition, by forming a conductive ring in the wiring hole 1b, after the electrode ring 31 is connected to the conductive ring through the lead 32, the electrode ring 31 can be energized through the conductive ring and the lead 32 above the glass substrate 1. Therefore, the external flexible circuit board can be electrically connected to multiple conductive rings above the glass substrate 1. Therefore, the flexible circuit board and its packaging structure no longer occupy the space below the glass substrate 1, so as to support the glass substrate 1 to be sufficiently close to the substrate to be printed, sufficiently reduce the printing height, and also increase the adjustment range of the printing height. The packaging position of the flexible circuit board will not affect the printing height, will not interfere with the printing process, and ensure the normal operation of the printing process.

[0131] Reference Figure 2-Figure 4 Another embodiment of the present application provides an electrofluidic nozzle, including an ejection plate and an ink cartridge connected to the top surface of the ejection plate; the ejection plate includes:

[0132] A glass substrate 1 is provided with a plurality of through-spray holes 1a and a plurality of wiring holes 1b on the bottom surface of the glass substrate 1, wherein the plurality of wiring holes 1b correspond to the plurality of spray holes 1a one by one; a sinking annular groove 1c is provided on the bottom surface of the glass substrate 1 near the plurality of spray holes 1a to form a plurality of spray bosses 11 at the bottom of the glass substrate 1.

[0133] A plurality of conductive rings are respectively disposed in the plurality of wiring holes 1 b , and the top ends of the conductive rings extend to the top surface of the glass substrate 1 , and the bottom ends of the conductive rings extend to the bottom surface of the glass substrate 1 .

[0134] A plurality of electrode rings 31 are respectively arranged around the outer sides of the plurality of injection bosses 11 , and the electrode rings 31 are arranged at the bottom of the sinking ring groove 1 c or the bottom surface of the glass substrate 1 .

[0135] A plurality of lead wires 32, each of which corresponds to a plurality of electrode rings 31, and both ends of the lead wires 32 are electrically connected to the electrode rings 31 and the bottom end of the conductive ring respectively; wherein,

[0136] The top ends of the plurality of conductive rings are used for electrical connection to an external flexible printed circuit board.

[0137] Since the ejection plate of the electrofluidic nozzle is processed by the processing technology of the electrofluidic nozzle with controllable printing height, the beneficial effects of the electrofluidic nozzle are consistent with the beneficial effects of the processing technology of the electrofluidic nozzle with controllable printing height, which will not be repeated here.

[0138] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0139] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0140] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A process for printing a highly controllable electrofluid nozzle, characterized in that: The following steps are involved: obtaining a glass substrate; Processing array nozzles and wiring holes corresponding to each nozzle on the bottom surface of the glass substrate; On the bottom surface of the glass substrate, a sinking annular groove is provided around each spray hole to form a plurality of spray bosses; Forming a seed layer on a glass substrate, the seed layer being attached to the surface of the glass substrate and the walls of all nozzle holes and all wiring holes, dividing the seed layer to form electroplating areas and non-electroplating areas on both the top and bottom surfaces of the glass substrate, all nozzle holes being located in the non-electroplating areas, and all wiring holes being located in the electroplating areas; Forming a first conductive layer in the electroplating area, removing excess first conductive layer, and retaining the first conductive layer on the inner wall of the wiring hole and around the opening of the wiring hole to form a conductive ring; Patterning a second conductive layer, the second conductive layer includes a plurality of electrode rings and a plurality of leads, the plurality of electrode rings respectively surround the outer sides of the plurality of injection bosses, the plurality of leads respectively electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings, and the tops of the plurality of conductive rings are connected to an external flexible circuit board; Covering the surface of the second conductive layer with a protective layer; Complete the processing of the injection plate of the electrofluid nozzle.

2. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: A sinking annular groove is provided around each spray hole to form a plurality of spray bosses, including: Laser etching to form the sunken ring groove; The groove wall of the sinking ring groove is modified by CNC machining so that the groove wall slope of the sinking ring groove is 50-80 degrees.

3. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The height of the injection boss is not greater than the depth of the sinking ring groove, and the height range of the injection boss includes 50-150 microns.

4. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The diameter of the injection end surface of the injection boss is 2-5 times the diameter of the injection hole.

5. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The method of dividing the seed layer to form an electroplating area and a non-electroplating area on both the top surface and the bottom surface of the glass substrate comprises: On the top and bottom surfaces of the glass substrate, the orthographic projection of the outer frame edge line of the sunken annular groove is used as the projection line. According to the projection lines of all the sunken annular grooves, a partition frame is preset on the top and bottom surfaces of the glass substrate, and all the projection lines on one side of the glass substrate are located within the partition frame. The minimum spacing between each projection line and the partition frame is set to the preset spacing spacing, thereby determining the position of each frame line of the partition frame; According to the position of the partition frame, the seed layer at the frame line of the partition frame is removed by laser etching to form an electroplating area and a non-electroplating area on both the bottom surface and the top surface of the glass substrate.

6. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The patterned second conductive layer includes a plurality of electrode rings and a plurality of leads, wherein the plurality of electrode rings surround the outer sides of the plurality of injection bosses respectively, and the plurality of leads electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings respectively, including: A second conductive layer is formed on the bottom surface of the glass substrate, and an electrode ring of the second conductive layer is arranged around the sinking ring groove.

7. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The patterned second conductive layer includes a plurality of electrode rings and a plurality of leads, wherein the plurality of electrode rings surround the outer sides of the plurality of injection bosses respectively, and the plurality of leads electrically connect the plurality of electrode rings to the bottoms of the plurality of conductive rings respectively, including: The second conductive layer is formed on the bottom surface of the glass substrate and in the groove of the sinking ring groove, the electrode ring of the second conductive layer is formed on the groove bottom of the sinking ring groove, and the lead wire of the second conductive layer is formed on the groove wall of the sinking ring groove and the bottom surface of the glass substrate.

8. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: After forming the first conductive layer in the electroplating area, removing the redundant first conductive layer, retaining the first conductive layer on the inner wall of the wiring hole and around the opening of the wiring hole to form a conductive ring, the method further includes: The inkjet printing process is used to fill the wiring holes with conductive material to form conductive columns.

9. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: A second conductive layer is also formed on the top surface of the glass substrate. A plurality of electrode rings of the second conductive layer located on the top surface of the glass substrate surround the plurality of nozzles respectively. A plurality of leads of the second conductive layer located on the top surface of the glass substrate correspond one-to-one to the plurality of electrode rings. One end of the lead is electrically connected to the electrode ring, and the other end of the lead is electrically connected to the external flexible circuit board.

10. The process for manufacturing an electrofluidic nozzle with controllable printing height according to claim 1, characterized in that: The protective layer covering the surface of the second conductive layer comprises: The passivation layer is covered on the surface of the second conductive layer by using a spray glue and metal stripping process; A hydrophobic layer is sputtered on the surface of the passivation layer.

11. An electrofluid nozzle, characterized in that: The invention comprises an injection plate and an ink cartridge connected to the top surface of the injection plate; the injection plate comprises: A glass substrate, wherein a plurality of through-spray holes and a plurality of wiring holes are formed on the bottom surface of the glass substrate, and the plurality of wiring holes correspond to the plurality of spray holes one by one; a sinking annular groove is formed on the bottom surface of the glass substrate near the plurality of spray holes to form a plurality of spray bosses at the bottom of the glass substrate; A plurality of conductive rings, wherein the plurality of conductive rings are respectively inserted into the plurality of wiring holes, and the top ends of the conductive rings extend to the top surface of the glass substrate, and the bottom ends of the conductive rings extend to the bottom surface of the glass substrate; A plurality of electrode rings, each of which surrounds the outer sides of the plurality of injection bosses, and the electrode rings are arranged at the bottom of the sinking ring groove or the bottom surface of the glass substrate; A plurality of lead wires, each of which corresponds to each of the plurality of electrode rings, and both ends of each lead wire are electrically connected to the bottom ends of the electrode rings and the conductive rings, respectively; wherein, The top ends of the plurality of conductive rings are electrically connected to an external flexible printed circuit board.

Images