An electro-fluidic jet head and an electro-fluidic jet device

Abstract

The application discloses an electro-fluidic jet head and an electro-fluidic jet device. The electro-fluidic jet head comprises an insulating substrate, a plurality of first electrodes and a plurality of second electrodes, the first electrodes and the second electrodes are arranged on two opposite surfaces of the insulating substrate; the insulating substrate comprises a plurality of substrate vias penetrating through the insulating substrate; the first electrodes comprise first through holes corresponding to the substrate vias, and the second electrodes comprise second through holes corresponding to the substrate vias; the first electrodes and the second electrodes are used for forming an electric field at both ends of the substrate vias so that a printing medium in the electro-fluidic jet head is jetted from the substrate vias. According to the technical scheme of the application, a plurality of substrate vias are arranged in the insulating substrate, an electric field is formed at both ends of the substrate vias so that the printing medium in the electro-fluidic jet head is jetted from the substrate vias to form a Taylor cone, the problem of electric field crosstalk between the substrate vias is prevented, and the reliability of the electro-fluidic jet head in strong electric field operation is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of inkjet printing technology, and in particular to an electrohydrodynamic inkjet head and an electrohydrodynamic inkjet device. BACKGROUND

[0002] Currently, the array type inkjet printing heads on the market are mainly piezoelectric type and thermal bubble type. These two types of inkjet heads use the extrusion force generated by the piezoelectric ceramic vibration or the expansion of the vapor bubble generated by local heating as the driving force to extrude the ink from the nozzle. Due to the limitation of the extrusion force principle, the liquid droplets ejected by these two types of inkjet heads are generally comparable to the diameter of the nozzle. With the decrease of the nozzle diameter, the viscous force and surface tension that the ink needs to overcome will increase, thus there are disadvantages such as low printing resolution and narrow range of ink viscosity.

[0003] Electrohydrodynamic inkjet technology is another technology with very promising application prospects. The principle of this technology is to apply a high voltage between the nozzle and the substrate, so that the meniscus at the nozzle deforms into a Taylor cone under the action of a strong electric field, and a liquid droplet with a size much smaller than the nozzle is ejected from the tip of the cone. Similar to traditional inkjet heads, electrohydrodynamic inkjet technology must be arrayed to adapt to large-scale industrial applications. However, the array type electrohydrodynamic inkjet head in the prior art has a complex structure, is difficult to manufacture, and is difficult to overcome the problem of crosstalk between nozzles. SUMMARY

[0004] The present application provides an electrohydrodynamic inkjet head and an electrohydrodynamic inkjet device to solve the problem of complex structure of the electrohydrodynamic inkjet head in the prior art and the crosstalk between nozzles.

[0005] According to an aspect of the present application, an electrohydrodynamic inkjet head is provided, which comprises:

[0006] an insulating substrate, a plurality of first electrodes and a plurality of second electrodes, the first electrodes and the second electrodes being arranged on the two opposite surfaces of the insulating substrate;

[0007] the insulating substrate comprises a plurality of substrate vias penetrating through the insulating substrate;

[0008] the first electrodes comprise first through holes corresponding to the substrate vias, and the second electrodes comprise second through holes corresponding to the substrate vias;

[0009] the first electrodes and the second electrodes are used to form an electric field at both ends of the substrate vias so that a printing medium in the electrohydrodynamic inkjet head is ejected from the substrate vias.

[0010] Optionally, the insulating substrate comprises a polyimide substrate.

[0011] Optionally, the electrohydrodynamic inkjet head further comprises a conical nozzle.

[0012] The conical nozzle is arranged in the substrate via.

[0013] Optionally, the first electrode comprises a surrounding part and a connecting part;

[0014] The surrounding part is connected with the connecting part, the surrounding part comprises a first through hole, and the connecting part is used for electrically connecting with the driving power supply.

[0015] Optionally, a plurality of connecting parts are used for electrically connecting with the same driving power supply.

[0016] Optionally, a plurality of second electrodes are connected with each other and electrically connected with the driving power supply.

[0017] Optionally, the electrofluidic jetting head further comprises a plurality of switching devices;

[0018] The switching devices are arranged in series in a loop between the first electrode and the second electrode.

[0019] Optionally, each switching unit is electrically connected with one first electrode and one second electrode.

[0020] Alternatively, each switching unit is electrically connected with at least two first electrodes and at least two second electrodes.

[0021] According to another aspect of the present application, an electrofluidic jetting device is provided, comprising an electrofluidic jetting head;

[0022] Further comprising: an ink cavity;

[0023] The ink cavity is arranged on the side of the second electrode away from the insulating substrate, the ink cavity stores a printing medium, and the surface of the ink cavity is provided with an ink cavity opening, which is in communication with the substrate via hole.

[0024] Optionally, the electrofluidic jetting device further comprises: a porous membrane layer;

[0025] The porous membrane layer is arranged between the ink cavity and the second electrode.

[0026] The technical scheme of the present application, by arranging a plurality of substrate via holes in the insulating substrate, the plurality of substrate via holes are arranged in an array in the insulating substrate, the substrate via holes are insulated by the insulating substrate, a first electrode and a second electrode are arranged at both ends of each substrate via hole, and an electric field is formed at both ends of the substrate via hole to make the printing medium in the electrofluidic jetting head form a Taylor cone jet from the substrate via hole, which ensures that the electrofluidic jetting head is jetted at the same time, the electrofluidic jetting head is integrated in the insulating substrate, the problem of electric field crosstalk between the substrate via holes is prevented, and the reliability of the electrofluidic jetting head operating under a strong electric field is ensured.

[0027] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments description will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and all other drawings obtained by those skilled in the art without creative effort based on these drawings should fall within the protection scope of the present application.

[0029] Figure 1 is a structural schematic diagram of a first electro-fluidic jet head according to an embodiment of the present application;

[0030] Figure 2 is a top view structural schematic diagram of an electro-fluidic jet head according to an embodiment of the present application;

[0031] Figure 3 is a structural schematic diagram of a second electrode according to an embodiment of the present application;

[0032] Figure 4 is Figure 2 is a sectional view structural schematic diagram along the section line A-A direction;

[0033] Figure 5 is Figure 4 is an enlarged structural schematic diagram at B;

[0034] Figure 6 is a structural schematic diagram of a second electro-fluidic jet head according to an embodiment of the present application;

[0035] Figure 7 is a working schematic diagram of an electro-fluidic jet head according to an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments only constitute some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present application.

[0037] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0038] Figure 1is a structural schematic diagram of a first electro-fluidic jetting head according to an embodiment of the present application, Figure 2 is a top view structural schematic diagram of an electro-fluidic jetting head according to an embodiment of the present application, Figure 3 is a structural schematic diagram of a second electrode according to an embodiment of the present application, Figure 4 is Figure 2 is a cross-sectional structural schematic diagram along the direction of section line A-A, the present embodiment can be applied to the scenario of inkjet printing, as shown in Figure 1 、 Figure 2 、 Figure 3 and Figure 4 , the electro-fluidic jetting head comprises:

[0039] an insulating substrate 1, a plurality of first electrodes 2 and a plurality of second electrodes 3, the first electrodes 2 and the second electrodes 3 are arranged on the two opposite surfaces of the insulating substrate 1;

[0040] the insulating substrate 1 comprises a plurality of substrate vias 11 penetrating the insulating substrate 1;

[0041] the first electrodes 2 comprise first through holes 21 corresponding to the substrate vias 11, and the second electrodes 3 comprise second through holes 31 corresponding to the substrate vias 11;

[0042] the first electrodes 2 and the second electrodes 3 are used to form an electric field at both ends of the substrate via 11 so that the printing medium in the electro-fluidic jetting head is ejected from the substrate via 11.

[0043] wherein the insulating substrate 1 can be a thin film substrate made of a material with good insulation, a plurality of substrate vias 11 are arranged in the insulating substrate 1, the plurality of substrate vias 11 can be arranged in an array in the insulating substrate 1, and the substrate vias 11 are insulated by the insulating substrate 1. Due to the good insulation of the insulating substrate 1, the influence of electrical crosstalk between the substrate vias 11 can be reduced when the plurality of substrate vias 11 generate an electric field.

[0044] The substrate via hole 11 forms a first hole and a second hole on the surface of the insulating substrate 1, the printing medium ejection direction is set as the y direction, the printing medium ejection direction is the direction in which the second hole points to the first hole, the first electrode 2 can be an extraction electrode of the electrofluidic jet printing head, the extraction electrode includes a first through hole 21 corresponding to the first hole, the extraction electrode is arranged on the surface of the insulating substrate 1 corresponding to the first hole, the first through hole 21 of each extraction electrode is arranged around the corresponding first hole, each first electrode 2 can include one first through hole 21, the number of first through holes 21 corresponds to the number of first holes; the second electrode 3 can be a conductive layer of the electrofluidic jet printing head, the conductive layer includes a second through hole 31 corresponding to the second hole, the conductive layer is arranged on the surface of the insulating substrate 1 corresponding to the second hole, the conductive layer can be arranged in an entire layer, the conductive layer includes a second through hole 31 corresponding to the number of second holes, and the second through hole 31 corresponds to the second hole. It can be understood that the first electrode 2 and the second electrode 3 are both metal electrodes, for example, the material of the first electrode 2 can be a copper film. The first electrode 2 and the second electrode 3 are used to form an electric field at both ends of the substrate via hole 11 when the first electrode 2 and the second electrode 3 are connected to form a loop, so that the printing medium in the substrate via hole 11 forms a Taylor cone under the action of a strong electric field, and the ejection of the printing medium is realized.

[0045] In some embodiments, the central axis of the substrate via hole 11, the central axis of the first through hole 21 and the central axis of the second through hole 31 are collinear. Since the substrate via hole 11 corresponds to the ejection channel of the printing medium, the central axis of the substrate via hole 11, the central axis of the first through hole 21 and the central axis of the second through hole 31 are collinear, which can improve the symmetry of the Taylor cone and the jet flow, and also improve the integration of the substrate via hole 11, which is suitable for large-scale integrated use.

[0046] Specifically, the jet printing mode of the electrofluidic jet printing head is as follows: the first electrode 2 and the second electrode 3 are connected with the positive electrode and the negative electrode of the power supply respectively to form a loop. When the power supply is not turned on, the loop is not connected, the first electrode 2 is in a suspended state, and there is no electric field between the first electrode 2 and the second electrode 3, so that the Taylor cone jet cannot be formed in the substrate via hole 11; when the power supply is turned on, the loop is connected, and a strong electric field exists between the first electrode 2 and the second electrode 3, the printing medium forms a Taylor cone and is ejected in the substrate via hole 11, and the jet printing of the electrofluidic jet printing head is realized.

[0047] It can be understood that in the prior art, the distance between the electrofluidic inkjet heads in the array is reduced for better integration. Since the working environment of the electrofluidic inkjet head is a strong electric field environment, when the electrofluidic inkjet heads work together or individually, the printing medium has a corresponding electrical property. The small distance between the electrofluidic inkjet heads causes the printing medium between different electrofluidic inkjet heads to have an electric field repulsion force, which affects the collimation of the printing medium jet. The dielectric constant of the insulating substrate 1 is low, and the insulating substrate 1 is filled between the substrate vias 11 to prevent crosstalk when the electrofluidic inkjet heads work.

[0048] The technical scheme of the embodiment of the present application provides a plurality of substrate vias in the insulating substrate, the substrate vias are arranged in an array in the insulating substrate, the substrate vias are isolated by the insulating substrate, a first electrode and a second electrode are respectively provided at both ends of each substrate via, and an electric field is formed at both ends of the substrate via to cause the printing medium in the electrofluidic inkjet head to form a Taylor cone jet from the substrate via, thereby ensuring that the electrofluidic inkjet heads can be integrated in the insulating substrate while jetting, preventing crosstalk between the substrate vias, and ensuring the reliability of the electrofluidic inkjet heads in a strong electric field.

[0049] Optionally, the insulating substrate includes a polyimide substrate (not shown in the figure).

[0050] The polyimide substrate has good electrical insulation, high temperature stability, and easy processing performance.

[0051] Specifically, during the processing of the electrofluidic inkjet head, a high-temperature liquid polyimide material can be injected into an injection mold for pressure forming, and laser engraving, drilling, or other forms can be used to form a plurality of substrate via microstructures on the polyimide substrate. At the same time, the polyimide substrate has strong corrosion resistance, so the quality requirement for the printing medium is low. The polyimide substrate has good high-temperature stability, so the electrofluidic inkjet head can maintain good dimensional stability at high temperatures and is not prone to expansion and contraction.

[0052] The technical scheme of the embodiment of the present application uses a polyimide substrate, which utilizes the good electrical insulation, high temperature stability, and easy processing performance of the polyimide material to solve the problem of complex electrofluidic inkjet head manufacturing and low reliability, ensure the anti-crosstalk function of the polyimide substrate, and improve the reliability of the electrofluidic inkjet head in a high-voltage environment.

[0053] Optionally, Figure 5 is Figure 4 The enlarged structural schematic diagram at B, combined with Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5As shown, the electrofluidic ejection head further comprises a conical nozzle 12;

[0054] The conical nozzle 12 is arranged in the substrate via 11.

[0055] The conical nozzle 12 can be used to eject a printing medium, and the conical nozzle 12 can comprise a second via penetrating the conical nozzle 12, a central axis of the second via being collinear with a central axis of the substrate via 11, and a cross-sectional area of the conical nozzle 12 perpendicular to an axis of the conical nozzle 12 gradually decreases along the y direction.

[0056] In some embodiments using polyimide as the substrate, a high aspect ratio conical nozzle 12 structure can be machined, with a relative height higher than the capillary scale. During operation, even if a small amount of ink spills out of the conical nozzle 12, a droplet will be formed under the action of the surface tension of the conical nozzle 12, detaching from the conical nozzle 12 wetting, without affecting the shape of the meniscus of the conical nozzle 12 and the formation of the Taylor cone, ensuring the printing accuracy of the electrofluidic ejection head.

[0057] The technical scheme of the embodiment of the present application sets a conical nozzle structure in the substrate via, so that when the printing medium overflows under the action of gravity, a droplet is formed under the action of the capillary force of the tip of the conical nozzle, and the droplet separates from the nozzle, without affecting the shape of the meniscus and the ejection, so that the printing accuracy of the electrofluidic ejection head is higher, the printing resolution is higher, and the application range is wider; the central axis of the second via is collinear with the central axis of the substrate via, which is conducive to improving the symmetry of the Taylor cone and the jet, and also improves the integration of the conical nozzle, and is suitable for large-scale integrated use.

[0058] Optionally, with reference to Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the first electrode 2 comprises a surrounding part 22 and a connecting part 23;

[0059] The surrounding part 22 is connected with the connecting part 23, and the surrounding part 22 comprises the first through hole 21; the connecting part 23 is used for electrical connection with the driving power supply.

[0060] The surrounding part 22 is used for surrounding the first hole, and each surrounding part 22 corresponds to one first hole or multiple first holes. The surrounding part 22 is connected with the connecting part 23, and the connecting part 23 is electrically connected with the driving power supply. The connecting part 23 is used for supplying power to the surrounding part 22 through the driving power supply, so that the surrounding part 22 cooperates with the second electrode 3 to form an electric field between the substrate vias 11.

[0061] In some embodiments, the surrounding part 22 can be annular, and the central axis of the surrounding part 22 can be collinear with the central axis of the substrate via hole 11, thereby improving the symmetry of the Taylor cone and the jet. The surrounding part 22 can also be of other shapes, and the embodiments of the present application do not limit this; the connecting part 23 can be an extension structure outside the surrounding part 22, and the extension structure can be connected to the driving power source independently or jointly, thereby achieving electrical connection to the first electrode 2.

[0062] The first electrode 2 can be prepared by image transfer technology such as direct writing printing and screen printing, which is simple to process, low in cost, and convenient for large-scale production and accurate matching with the substrate via hole 11.

[0063] In some embodiments, continuing to refer to Figure 4 As shown in the figure, the electrofluidic jet printing head further comprises a second insulating substrate 10, which is arranged on the side of the first electrode 2 away from the insulating substrate 1, and the second insulating substrate 10 further comprises a second substrate via hole corresponding to the substrate via hole 11. The substrate via hole 11, the first through hole 21 and the second substrate via hole form a jet path of the printing medium, which ensures the jet path of the printing medium and protects the first electrode 2 from scratching during the working process of the electrofluidic jet printing head, thereby affecting the normal working of the electrofluidic jet printing head.

[0064] The technical scheme of the embodiments of the present application divides the first electrode into a surrounding part and a connecting part, so that the surrounding part surrounds the substrate via hole, and the connecting part is connected to the driving power source, thereby ensuring one-to-one correspondence between the substrate via hole and the surrounding part and accurate matching between the substrate via hole and the first electrode.

[0065] Optionally, continuing to refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown in the figure, the plurality of connecting parts 23 are used for electrical connection to the same driving power source.

[0066] In the above embodiments, the first electrode 2 can be arranged on one side of the insulating substrate 1 in a non-integral layer, and the plurality of connecting parts 23 can have a convergence point, the plurality of connecting parts 23 converge at the convergence point, and the driving power source is directly connected to the convergence point. When the driving power source is started, the driving power source can simultaneously supply power to the plurality of surrounding parts 22, thereby achieving common control of the driving power source to the plurality of first electrodes 2 and realizing the on-off of the voltage. In this way, it is possible to avoid arranging a corresponding driving power source for each first electrode 2, thereby simplifying the structure of the electrofluidic jet printing head and saving the cost of the electrofluidic jet printing device.

[0067] Optionally, continuing to refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown in the figure, the plurality of second electrodes 3 are connected to each other and are electrically connected to the driving power source.

[0068] The second electrode 3 can be arranged on one side of the insulating substrate 1, and the second electrode 3 can be connected to each other, so that the driving power supply can be controlled at the same time. The second through hole 31 on the second electrode 3, the first through hole 21 on the first electrode 2 and the substrate through hole 11 form a printing medium ejection path, so that the corresponding driving power supply can be avoided for the single second electrode 3, the structure of the electrofluidic inkjet head is simplified, and the cost of the electrofluidic inkjet device is saved.

[0069] In some embodiments, the second electrode 3 can be prepared by direct writing printing, screen printing and other image transfer technologies, which is simple, low in cost, easy for mass production and easy for accurate matching with the substrate through hole 11.

[0070] For example, when the driving power supply is started, the positive and negative poles of the driving power supply are connected to the first electrode 2 and the second electrode 3 respectively. Since the first electrode 2 is connected to each other through the connecting part 23, and the second electrode 3 is also connected to each other, when the driving power supply is started, a strong electric field is generated on both sides of all the substrate through holes 11 at the same time, the printing medium overcomes the surface tension of the meniscus to form a Taylor cone and then ejects the printing.

[0071] It can be understood that the plurality of second electrodes 3 in the embodiment of the application can also include part of the second electrodes 3 instead of all the second electrodes 3, which can be determined according to the application scene of the electrofluidic inkjet head, and the embodiment of the application does not limit this.

[0072] In some embodiments, Figure 6 is a structure schematic diagram of a second electrofluidic inkjet head provided by the embodiment of the application, as shown in Figure 6 The electrofluidic inkjet head further comprises an acceleration electrode 4, and the acceleration electrode 4 is also a metal electrode structure. The acceleration electrode 4 is arranged on the side, away from the insulating substrate 1, of the first electrode 2. After the printing medium passes through the first electrode 2, the printing medium can be easily adsorbed by the first electrode 2 due to the opposite charges between the printing medium and the first electrode 2. The acceleration electrode 4 with the same electrical property as the printing medium is arranged to exert a repulsive force on the printing medium according to the principle of like charges repel each other, so as to accelerate the ejection of the printing medium and optimize the directionality of the ejection of the printing medium, thereby improving the efficiency of the electrofluidic inkjet device. It can be understood that the acceleration electrode 4 also has a power supply device connected thereto to supply power to the acceleration electrode 4.

[0073] Optionally, Figure 7 is a working schematic diagram of an electrofluidic inkjet head provided by the embodiment of the application, which is combined with Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 7 The electrofluidic inkjet head further comprises a plurality of switch devices 5.

[0074] The switch device 5 is arranged in series in the loop between the first electrode 2 and the second electrode 3.

[0075] The switch device 5 can be a relay or a field effect transistor commonly used in circuit connection, for controlling the on-off of the loop between the first electrode 2 and the second electrode 3.

[0076] Specifically, the positive pole of the driving power source 6 is connected to all the second electrodes 3, and the driving power source 6 controls the on-off of the second electrodes 3 at the same time, and the negative pole of the driving power source 6 is connected to the corresponding first electrode 2 through the switch device 5, and the number of the first electrode 2 corresponds to the number of the switch device 5, so as to realize independent control of each first electrode 2, that is, the driving power source 6, the switch device 5, the first electrode 2 and the second electrode 3 form a loop corresponding to the substrate via hole 11, and only when the driving power source 6 is started and the switch device 5 is closed, an electric field can be formed between the corresponding substrate via holes 11, so as to realize independent control of each substrate via hole 11.

[0077] It can be understood that the driving power source 6 independently controls any one of the first electrode 2 and the second electrode 3, that is, the independent control of the substrate via hole 11 is realized, that is, the independent control of the ejection of the e-fluid jet head is realized, and the application scenarios of the e-fluid jet head are increased by such arrangement. In some embodiments, each switch unit is electrically connected to one first electrode 2 and one second electrode 3; or each switch unit is electrically connected to at least two first electrodes 2 and at least two second electrodes 3. That is, the switch unit can be arranged in the loop of each first electrode 2 and each second electrode 3, so as to realize independent control of each substrate via hole 11; or the switch unit can be arranged in the loop of multiple first electrodes 2 and multiple second electrodes 3, so as to realize independent control of multiple substrate via holes 11, and the embodiments of the present application do not limit this.

[0078] The technical scheme of the embodiment of the present application realizes independent control of the substrate via hole by arranging the switch device corresponding to the substrate via hole in the loop of the first electrode and the second electrode without adding the driving power source, and controls the on-off of the switch device, so as to realize independent control of the substrate via hole, without arranging multiple separate driving power sources, thereby reducing the complexity and cost of the system.

[0079] Based on the same inventive concept, the embodiment of the present application further provides an e-fluid jet device, which continues to refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 7 as shown, which comprises an e-fluid jet head.

[0080] Further comprising: an ink cavity 7.

[0081] The ink cavity 7 is arranged on the side of the second electrode 3 away from the insulating substrate 1, and a printing medium is stored in the ink cavity 7, and the ink cavity 7 is provided with an ink cavity 7 opening, which is in communication with the substrate via hole 11.

[0082] The ink cavity 7 can be used to store a printing medium, which can be ink or other printing solution, and the embodiment of the present application does not limit this.

[0083] In some embodiments, the pressure in the ink cavity 7 is slightly lower than the ambient air pressure, so that the liquid in the meniscus of the substrate via hole 11 is kept in a micro-negative pressure state, preventing the printing medium from overflowing from the substrate via hole 11 when no electric field is applied between the substrate via holes 11; when a voltage is applied between the substrate via holes 11, the meniscus deforms to form a Taylor cone, and the electric field force is greater than the surface tension, so that the printing medium spontaneously flows under the action of the electric field force, without the need for an additional ink supply pump.

[0084] The technical scheme of the embodiment of the present application provides an ink cavity in the electrofluidic jet printing device, without the need for an additional ink supply device, and the flow and supply of the printing medium are realized by using a strong electric field between the substrate via holes, which simplifies the cost of the electrofluidic jet printing device and ensures the accuracy of the electrofluidic jet printing device.

[0085] Optionally, continuing to refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 7 , the electrofluidic jet printing device further comprises a porous membrane layer 8.

[0086] The porous membrane layer 8 is arranged between the ink cavity 7 and the second electrode 3.

[0087] The porous membrane layer 8 is arranged between the ink cavity 7 and the second electrode 3, and when the printing medium is jetted from the substrate via hole 11 to the porous membrane layer 8, the porous membrane layer 8 can increase the flow resistance, improve the uniformity of the distribution of the printing medium between the substrate via holes 11, make the shape of each meniscus more consistent, prevent adjacent substrate via holes 11 from forming flow crosstalk to the working substrate via hole 11 when the substrate via hole 11 is working alone, and improve the accuracy of the electrofluidic jet printing device.

[0088] In addition, the porous membrane layer 8 also has a filtering effect, preventing small particles in the printing medium from affecting the accuracy of the jet printing.

[0089] The above detailed description does not limit the scope of the application. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the application shall be included in the scope of the application.

Claims

1. An electrofluidic jet head, characterized by, The electric fluid ejection head comprises: an insulating substrate, a plurality of first electrodes and a plurality of second electrodes, the first electrodes and the second electrodes are arranged on two opposite surfaces of the insulating substrate; the insulating substrate comprises a plurality of substrate vias penetrating through the insulating substrate; the first electrodes comprise first through holes corresponding to the substrate vias, and the second electrodes comprise second through holes corresponding to the substrate vias; the first electrodes and the second electrodes are used to form an electric field across the substrate vias so that a printing medium in the electric fluid ejection head is ejected from the substrate vias; the electric fluid ejection head further comprises a conical nozzle; the conical nozzle is arranged in the substrate via.

2. The electrofluidic jet head of claim 1, wherein, The insulating substrate comprises a polyimide substrate.

3. The electrofluidic jet head of claim 1, wherein, The first electrode comprises a surrounding part and a connecting part; the surrounding part is connected to the connecting part, the surrounding part comprises the first through hole, and the connecting part is used to be electrically connected to a driving power source.

4. The electrofluidic jet head of claim 3, wherein, A plurality of the connecting parts are used to be electrically connected to the same driving power source.

5. The electrofluidic jet head of claim 1, wherein, A plurality of the second electrodes are connected to each other and are electrically connected to a driving power source.

6. The electrofluidic jet head of claim 1, wherein, The electric fluid ejection head further comprises a plurality of switching devices; the switching devices are arranged in series in a loop between the first electrodes and the second electrodes.

7. The electrofluidic jet head of claim 6, wherein, Each of the switching devices is electrically connected to one of the first electrodes and one of the second electrodes. Alternatively, each of the switching devices is electrically connected to at least two of the first electrodes and at least two of the second electrodes.

8. An electrofluidic jet device, characterized by The electric fluid ejection head according to any one of claims 1-7; further comprising an ink chamber; the ink chamber is arranged on a side of the second electrode away from the insulating substrate, the ink chamber stores a printing medium, and a surface of the ink chamber is provided with an ink chamber opening, the ink chamber opening is in communication with the substrate via.

9. The electrofluidic display device of claim 8, wherein, The electric fluid ejection device further comprises a porous membrane layer; the porous membrane layer is arranged between the ink chamber and the second electrode.

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