Printing head

Abstract

The utility model discloses a printing head. Comprising a liquid storage component for storing ink, a driving component and a spraying hole component, the driving component and the spraying hole component are located on the two sides of the liquid storage component respectively, and the driving component can enable the ink in the liquid storage component to be sprayed out of the spraying hole component; the driving component comprises piezoelectric ceramics; the piezoelectric ceramic is provided with an isolation part which isolates the piezoelectric ceramic to be matched with the liquid storage component.

Description

Technical Field

[0001] This application relates to the field of inkjet printing, and more particularly to a printhead. Background Technology

[0002] On-demand (OD) piezoelectric printheads are widely used for printing on a variety of substrates. Piezoelectric printheads are advantageous compared to thermal inkjet printheads when using jettable materials such as UV-curable inks, where the higher viscosity or chemical composition of the jettable material hinders the use of thermal inkjet for its DOD applications. Thermal inkjet printheads use a heating element actuator in the ink-fill chamber to vaporize the ink and generate bubbles that force the ink to drip from the nozzle. Therefore, suitable jettable materials for use in thermal inkjet printheads are limited to those whose composition can withstand boiling point temperatures without mechanical or chemical degradation. However, piezoelectric printheads can accommodate a wider selection of jettable materials because they use piezoelectric material actuators on the membrane of the ink-fill chamber to generate pressure pulses that force ink to drip from the nozzle.

[0003] However, one problem with piezoelectric printheads is mechanical crosstalk between adjacent nozzles. When the film in a given nozzle moves upward, the film in an adjacent nozzle moves downward a small distance. This negatively affects the operation of adjacent nozzles. Ideally, when a given nozzle is actuated (moving its film upward or downward), the films in adjacent nozzles should not be affected. More precisely, the films in adjacent nozzles should be completely independent and will not move detectably when a neighboring nozzle is actuated and its film moves. Utility Model Content

[0004] To address the problems existing in the prior art, this application provides a printhead.

[0005] In this application, the printhead ejects ink droplets downwards for printing. Therefore, the direction of ink ejection is defined as downwards, and vice versa.

[0006] The specific technical solution of this application is as follows:

[0007] 1. A printhead, comprising a liquid storage component for storing ink, a driving component, and a nozzle component, wherein the driving component and the nozzle component are respectively located on both sides of the liquid storage component, and the driving component enables the ink in the liquid storage component to be ejected from the nozzle component;

[0008] The driving component includes a piezoelectric ceramic; an isolation portion is provided on the piezoelectric ceramic to isolate the piezoelectric ceramic into a liquid storage component;

[0009] Preferably, the isolation portion is an isolation groove formed on the piezoelectric ceramic.

[0010] 2. The printhead according to item 1, wherein the liquid storage component includes a plurality of independent pressure chambers, ink is stored in the pressure chambers, and the piezoelectric ceramic covers one end of the pressure chamber; the isolation groove is formed between two adjacent pressure chambers;

[0011] Preferably, the liquid storage component includes a cavity wall forming a pressure chamber, the cavity wall is provided with multiple cavity walls, the cavity wall is connected to the piezoelectric ceramic, and the isolation groove is correspondingly opened at the connection between the cavity wall and the piezoelectric ceramic;

[0012] More preferably, the piezoelectric ceramic includes a vibration zone corresponding to the pressure chamber, the vibration zone being located at one end of the pressure chamber and sealing the pressure chamber, and the isolation groove being formed between two adjacent vibration zones.

[0013] 3. The printhead according to item 2, wherein, preferably, the depth of the isolation groove is 10% to 80% of the thickness of the piezoelectric ceramic;

[0014] Preferably, the depth of the isolation groove is 20% to 60% of the thickness of the piezoelectric ceramic;

[0015] More preferably, the depth of the isolation groove is 40% to 50% of the thickness of the piezoelectric ceramic.

[0016] 4. The printhead according to item 2, wherein the isolation groove is formed on the side of the piezoelectric ceramic near the liquid storage component;

[0017] Alternatively, the isolation groove is located on the side of the piezoelectric ceramic away from the liquid storage component.

[0018] 5. The printhead according to any one of items 1 to 4, wherein the isolation groove is filled with a release agent;

[0019] Preferably, a first adhesive layer is provided between the driving member and the liquid storage member;

[0020] More preferably, the first adhesive layer and the filler are made of the same material.

[0021] 6. The printhead according to any one of items 1 to 5, wherein the liquid storage component includes a cavity wall, the cavity wall being made of metal;

[0022] Preferably, the cavity wall is made of stainless steel or aluminum alloy.

[0023] 7. The printhead according to item 6, wherein a protective layer is provided on the cavity wall;

[0024] Preferably, the protective layer is an aluminum alloy layer;

[0025] More preferably, the protective layer is an aluminum oxide layer;

[0026] More preferably, when the cavity wall is made of aluminum alloy, the protective layer is an aluminum alloy layer.

[0027] 8. The printhead according to item 6, wherein a protective layer is provided on the cavity wall;

[0028] Preferably, the protective layer is a nitrided layer;

[0029] More preferably, the protective layer is an iron nitride layer;

[0030] More preferably, the protective layer is a nitrided stainless steel layer;

[0031] More preferably, when the cavity wall is made of stainless steel, the protective layer is a nitrided layer.

[0032] 9. The printhead according to any one of items 1 to 8, wherein the nozzle component includes a nozzle layer, and a plurality of nozzles corresponding to the liquid storage component are formed on the nozzle layer;

[0033] Preferably, the nozzle layer is made of metal;

[0034] More preferably, the nozzle layer is made of stainless steel or nickel alloy.

[0035] 10. The printhead according to item 9, wherein a second adhesive layer is provided between the nozzle component and the liquid storage component; the second adhesive layer is used for connecting the nozzle component and the liquid storage component;

[0036] Preferably, the second adhesive layer is disposed between the nozzle layer and the cavity wall;

[0037] More preferably, the second adhesive layer covers the nozzle layer;

[0038] More preferably, the second adhesive layer is an adhesive film, an epoxy layer, or an acrylic layer.

[0039] Beneficial effects

[0040] This application provides a printhead that reduces mechanical crosstalk on the piezoelectric ceramic by creating isolation grooves. This allows for more precise ink ejection from the printhead, thereby improving print quality. Furthermore, the printhead in this application, through the rational arrangement of component positions and specific connection methods, allows the entire printhead to be manufactured using metal, thus improving its wear resistance and lifespan.

[0041] The printhead provided in this application reduces mechanical crosstalk caused by piezoelectric ceramic vibration due to its isolation structure. This reduces the impact of adjacent vibration ranges during high-frequency printing, enabling the printhead to print at higher frequencies. The increased ignition frequency of the nozzles significantly improves the frequency at which the nozzles operate stably. Furthermore, a higher ignition frequency allows for the ejection of more ink within the same time frame, increasing the printhead's printing speed and thus its printing efficiency. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of one embodiment of the printhead in this application;

[0043] Figure 2 This is a schematic diagram of another embodiment of the printhead in this application;

[0044] Figure 3 This is a line graph showing the changes in data in Examples 1-4 and the comparative examples of this application.

[0045] In the figure, 1 is piezoelectric ceramic; 11 is isolation tank; 12 is electrode; 13 is first adhesive layer; 2 is liquid storage component; 21 is pressure chamber; 22 is chamber wall; 3 is nozzle component; 31 is nozzle layer; 32 is nozzle; 33 is second adhesive layer. Detailed Implementation

[0046] The present application will now be described in detail. While specific embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0047] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0048] refer to Figure 1This application provides a printhead. It includes a liquid storage component 2 for storing ink, a driving component, and a nozzle component 3. The driving component and the nozzle component 3 are located on both sides of the liquid storage component 2, and the driving component enables the ink in the liquid storage component 2 to be ejected from the nozzle component 3.

[0049] The ink reservoir 2 stores ink, and the drive component is the power source. During printing, the drive component generates power to propel the ink droplets in the ink reservoir 2 outwards. The nozzle component 3 provides a channel for ink to pass through, allowing the ink to be ejected.

[0050] The driving component includes a piezoelectric ceramic 1; an isolation portion is provided on the piezoelectric ceramic 1 to isolate the piezoelectric ceramic 1 into a liquid storage component 2.

[0051] The piezoelectric ceramic 1 is laid on the liquid storage component 2, and the piezoelectric ceramic 1 is a single-piece structure. Localized vibration of the piezoelectric ceramic 1 is achieved by setting a local drive on it. Therefore, when the piezoelectric ceramic 1 generates a driving force, adjacent piezoelectric ceramics 1 will experience mechanical crosstalk. This affects the vibration amplitude of the piezoelectric ceramic 1, and further affects the accuracy of the printhead.

[0052] Therefore, the piezoelectric ceramic 1 of this application is provided with an isolation section to isolate the vibration area of ​​the piezoelectric ceramic 1; thereby reducing the mechanical crosstalk of the piezoelectric ceramic 1; and thus improving the vibration accuracy of the piezoelectric ceramic 1, and improving the printing quality and accuracy of the print head. On the one hand, the isolation section can mechanically isolate the vibration area of ​​the piezoelectric ceramic 1; on the other hand, the piezoelectric ceramic 1 also needs to maintain a certain mechanical strength at the location of the isolation section to reduce the sealing performance of the piezoelectric ceramic 1 to the liquid storage component 2; and to maintain the vibration intensity and vibration stability of the piezoelectric ceramic 1. Therefore, the isolation section must not only isolate the piezoelectric ceramic 1 from mechanical crosstalk, but also ensure the connection strength between the various vibration areas of the piezoelectric ceramic 1.

[0053] The isolation section reduces mechanical crosstalk during vibration of the piezoelectric ceramic 1. This reduces the impact of vibration on adjacent areas of the piezoelectric ceramic 1 during printing, enabling stable printing at a high frequency. It also increases the ignition frequency of the piezoelectric ceramic 1, thereby improving printing efficiency. Furthermore, a higher ignition frequency within the same time frame allows for the ejection of more ink, increasing the print head's printing speed and significantly improving its printing efficiency.

[0054] The liquid storage component 2 includes multiple independent pressure chambers 21, in which ink is stored, and piezoelectric ceramic 1 covers one end of the pressure chamber 21; the nozzle component 3 includes a nozzle layer 31, on which multiple nozzles 32 corresponding to the liquid storage component 2 are formed.

[0055] The piezoelectric ceramic 1 can generate power, and it vibrates when energized. In turn, the piezoelectric ceramic 1 squeezes the ink droplets in the liquid storage component 2, causing the ink droplets in the liquid storage component 2 to be ejected from the nozzle component 3.

[0056] In one specific embodiment, the piezoelectric ceramic 1 is a one-piece molded structure, and the piezoelectric ceramic 1 covers all the pressure chambers 21 inside the liquid storage component 2.

[0057] In one specific embodiment, an electrode 12 is provided on the piezoelectric ceramic 1, and the electrode 12 includes a plurality of branch electrodes 12 disposed on the piezoelectric ceramic 1; by energizing the branch electrodes 12, the piezoelectric ceramic 1 can be driven to vibrate.

[0058] In this application, since the piezoelectric ceramic 1 is integrally formed, it is energized using the branch electrode 12. Therefore, when the piezoelectric ceramic 1 vibrates, the adjacent area will be affected by crosstalk from the mechanical vibration.

[0059] Therefore, by placing the isolation part between the vibration regions of the piezoelectric ceramic 1, the branch electrode 12 can reduce mechanical vibration crosstalk to the adjacent region when driving the piezoelectric ceramic 1 to vibrate locally.

[0060] In one specific embodiment, the isolation part is an isolation groove 11 formed on the piezoelectric ceramic 1.

[0061] The isolation groove 11 is located between the vibration areas of the piezoelectric ceramic 1. The isolation groove 11 is a groove structure and does not penetrate the piezoelectric ceramic 1. Therefore, at the location of the isolation groove 11, the piezoelectric ceramics 1 remain connected. Simultaneously, the isolation groove 11 removes some of the piezoelectric ceramic 1, resulting in a partially hollow structure. Therefore, when the piezoelectric ceramics 1 on both sides of the isolation groove 11 vibrate, the mechanical vibration generated is difficult to transmit through the isolation groove 11, thus reducing mechanical crosstalk between the vibration areas of the piezoelectric ceramic 1. This further reduces crosstalk between adjacent vibration areas when the piezoelectric ceramic 1 is driven to vibrate, thereby improving the accuracy of the piezoelectric ceramic 1 when driving liquid in the liquid storage component 2. This, in turn, improves the printing accuracy of the printhead.

[0062] The isolation groove 11 is located between two adjacent pressure chambers 21;

[0063] Preferably, the liquid storage component 2 includes a cavity wall 22 forming a pressure chamber 21. Multiple cavity walls 22 are provided. The cavity walls 22 are connected to the piezoelectric ceramic 1. The isolation groove 11 is correspondingly opened at the connection between the cavity wall 22 and the piezoelectric ceramic 1.

[0064] More preferably, the piezoelectric ceramic 1 includes a vibration zone corresponding to the pressure chamber 21, the vibration zone is located at one end of the pressure chamber 21 and seals the pressure chamber 21, and the isolation groove 11 is formed between two adjacent vibration zones.

[0065] When the piezoelectric ceramic 1 is connected to the liquid storage component 2, the piezoelectric ceramic 1 and the end face of the cavity wall 22 of the liquid storage component 2 are in direct contact and fixedly connected, thereby achieving a fixed connection between the liquid storage component 2 and the piezoelectric ceramic 1. At the same time, the connection between the piezoelectric ceramic 1 and the cavity wall 22 also seals the pressure chamber 21, thereby reducing the leakage of ink in the pressure chamber 21.

[0066] The vibration zone of the piezoelectric ceramic 1 corresponds to the pressure chamber 21 of the liquid storage component 2. Therefore, when the vibration zone of the piezoelectric ceramic 1 vibrates, it will compress the internal space of the pressure chamber 21 and squeeze out the ink in the pressure chamber 21.

[0067] The connection area is where the piezoelectric ceramic 1 connects to the cavity wall 22 of the liquid storage component 2. An isolation groove 11 is formed in the connection area. The width of the connection area corresponds to the thickness of the cavity wall 22. The width of the isolation groove 11 is related to the setting; those skilled in the art can determine the width of the isolation groove 11 based on the crosstalk intensity of the piezoelectric ceramic 1 during use, the specific operating environment of the printhead, and the combined consideration of the difficulty, intensity, and cost of the printhead processing technology. Therefore, it will not be elaborated further here.

[0068] In this application, the ink is located in the liquid storage component 2. Therefore, with the pressure chamber 21 as the reference, the position close to the center of the pressure chamber 21 is called the inside, and the position relatively far away from the pressure chamber 21 is called the outside.

[0069] The isolation groove 11 can be located either inside or outside the connection area.

[0070] In one specific embodiment, the isolation groove 11 is formed on the side of the piezoelectric ceramic 1 facing away from the liquid storage component 2.

[0071] That is, the isolation groove 11 is opened on the outside of the connection area of ​​the piezoelectric ceramic 1.

[0072] Therefore, the piezoelectric ceramic 1 is a single, integral structure on the inner side. When connecting to the cavity wall 22, the piezoelectric ceramic 1 also contacts the cavity wall 22 as a single, integral structure. Thus, although an isolation groove 11 is formed on the piezoelectric ceramic 1, it does not affect the connection strength between the piezoelectric ceramic 1 and the cavity wall 22. The piezoelectric ceramic 1 can seal the pressure chamber 21, and it is difficult to separate from the cavity wall 22. Therefore, the isolation groove 11 can ensure the connection stability between the piezoelectric ceramic 1 and the cavity wall 22 while also reducing the mechanical crosstalk of the piezoelectric ceramic 1, thereby improving the vibration accuracy of the piezoelectric ceramic 1 and the printing quality of the printhead.

[0073] The depth of the isolation groove 11 is 10% to 80% of the thickness of the piezoelectric ceramic 1;

[0074] Preferably, the depth of the isolation groove 11 is 20% to 60% of the thickness of the piezoelectric ceramic 1;

[0075] More preferably, the depth of the isolation groove 11 is 40% to 50% of the thickness of the piezoelectric ceramic 1.

[0076] The depth of the isolation groove 11 is 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% of the thickness of the piezoelectric ceramic 1.

[0077] In one specific embodiment, the isolation groove 11 is formed on the side of the piezoelectric ceramic 1 near the liquid storage component 2.

[0078] That is, the isolation groove 11 is opened on the inner side of the connection area of ​​the piezoelectric ceramic 1.

[0079] Since the inner side of the piezoelectric ceramic 1 is connected to the cavity wall 22, it is necessary to first open an isolation groove 11 on the inner side of the piezoelectric ceramic 1, and then connect and fix the piezoelectric ceramic 1 to the cavity wall 22.

[0080] In one specific embodiment, an isolation groove 11 is formed inside the piezoelectric ceramic 1, and the width of the isolation groove 11 is smaller than the width of the connection area. This allows the connection area to connect with the cavity wall 22, with the isolation groove 11 located between the piezoelectric ceramic 1 and the cavity wall 22.

[0081] In another specific embodiment, the isolation tank 11 is filled with an isolation agent;

[0082] An isolation groove 11 is also formed inside the piezoelectric ceramic 1, and the width of the isolation groove 11 is equal to or less than the width of the connection area. The isolation groove 11 is filled with a filler that is separate from the piezoelectric ceramic 1.

[0083] When the isolation groove 11 is located inside the piezoelectric ceramic 1, and the piezoelectric ceramic 1 is connected to the cavity wall 22, the pressure chamber 21 is located between the cavity wall 22 and the piezoelectric ceramic 1. In this case, the use of a filler can strengthen the connection between the piezoelectric ceramic 1 and the cavity wall 22. Simultaneously, the filler can also seal the piezoelectric ceramic 1, increasing the sealing performance between the piezoelectric ceramic 1 and the cavity wall 22, and reducing ink leakage in the pressure chamber 21. Furthermore, the filler can also strengthen the piezoelectric ceramic 1. When the piezoelectric ceramic 1 vibrates, the filler can absorb the vibrational kinetic energy of the piezoelectric ceramic 1 and the mechanical crosstalk between the vibration zones. It can also share the position of the piezoelectric ceramic 1 relative to the cavity wall 22 during vibration, thereby reducing the relative displacement amplitude between the piezoelectric ceramic 1 and the cavity wall 22, and thus improving the connection strength between the piezoelectric ceramic 1 and the cavity wall 22. This increases the service life of the printhead.

[0084] The depth of the isolation groove 11 is 10% to 80% of the thickness of the piezoelectric ceramic 1;

[0085] Preferably, the depth of the isolation groove 11 is 20% to 60% of the thickness of the piezoelectric ceramic 1;

[0086] More preferably, the depth of the isolation groove 11 is 40% to 50% of the thickness of the piezoelectric ceramic 1.

[0087] The depth of the isolation groove 11 is 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% of the thickness of the piezoelectric ceramic 1.

[0088] Preferably, a first adhesive layer 13 is provided between the driving component and the liquid storage component 2;

[0089] Preferably, the first adhesive layer 13 and the filler are made of the same material.

[0090] On the one hand, the first adhesive layer 13 can be used to connect the piezoelectric ceramic 1 and the liquid storage component 2, enabling the piezoelectric ceramic 1 and the liquid storage component 2 to be connected and sealed. On the other hand, by using the same material as the filler, the first adhesive layer 13 and the filler can be installed simultaneously when connecting the piezoelectric ceramic 1 to the cavity wall 22, reducing the processing steps of the filler and the first adhesive layer 13, simplifying the manufacturing steps of the filler and the first adhesive layer 13, and thus reducing the processing cost of the printhead.

[0091] The liquid storage component 2 includes a cavity wall 22, which is made of metal;

[0092] Preferably, the cavity wall 22 is made of stainless steel or aluminum alloy;

[0093] Preferably, the nozzle layer 31 is made of metal;

[0094] More preferably, the nozzle layer 31 is made of stainless steel or nickel alloy.

[0095] A protective layer is provided on the cavity wall 22;

[0096] Preferably, the protective layer is an aluminum alloy layer or a nitrided layer;

[0097] More preferably, the protective layer is an aluminum oxide layer, an iron nitride layer, or a carburized stainless steel layer.

[0098] Both the liquid storage component 2 and the nozzle layer 31 are made of metal components, which improves the strength and wear resistance of the liquid storage component 2 and the nozzle layer 31, making the manufactured printhead stronger and more resistant to impact. This not only reduces the safety of the printhead during transportation and the possibility of printhead failure during transportation, but also increases the service life of the printhead.

[0099] The ink is located in the pressure chamber 21, so the ink is in direct contact with the chamber wall 22. Different inks have different properties, and since the ink is a liquid, it is in direct contact with the chamber wall 22. Therefore, a protective layer is set to further protect the chamber wall 22, thereby reducing the possibility of the ink causing corrosion or impact damage to the chamber wall 22.

[0100] In one specific embodiment, the cavity wall 22 is made of stainless steel, and the nozzle layer 31 is made of stainless steel. The protective layer is an iron nitride layer or a nitrided stainless steel layer.

[0101] Both the cavity wall 22 and the nozzle layer 31 of the liquid storage component 2 are made of stainless steel. This reduces the possibility of electrochemical reactions between the nozzle layer 31 and the cavity wall 22. Furthermore, using the same material for the nozzle layer 31 and the cavity wall 22 can reduce manufacturing costs and difficulties.

[0102] In one specific embodiment, the cavity wall 22 is nitrided to form a dense layer of iron nitride or nitrided stainless steel on the surface of the stainless steel cavity wall 22, thereby improving the corrosion resistance and hardness of the cavity wall 22 and extending the lifespan of the printhead. Furthermore, the nitriding layer makes the surface of the cavity wall 22 smoother and more non-stick, reducing ink adhesion to the cavity wall and allowing the ink to flow out more smoothly from the cavity wall. This reduces resistance to ink flow during printing and improves printing efficiency.

[0103] In another specific embodiment, the cavity wall is made of aluminum alloy and the protective layer is an aluminum oxide layer.

[0104] Passivated aluminum alloy is more stable and corrosion-resistant than stainless steel. Therefore, using aluminum alloy to fabricate the cavity wall 22 improves its service life. Furthermore, an aluminum oxide layer is used to protect the aluminum alloy cavity wall 22, further reducing corrosion and other damage from ink, thus extending its service life.

[0105] Alumina structures are chosen for their low strength, ease of processing, low manufacturing cost, and excellent corrosion resistance. Furthermore, alumina's high density provides excellent protection for the cavity wall 22; therefore, an alumina layer is used to protect the cavity wall 22.

[0106] A second adhesive layer 33 is provided between the nozzle component 3 and the liquid storage component 2; the second adhesive layer 33 is used to connect the nozzle component 3 and the liquid storage component 2.

[0107] Preferably, the second adhesive layer 33 is disposed between the nozzle layer 31 and the cavity wall 22;

[0108] More preferably, the second adhesive layer 33 covers the nozzle layer 32;

[0109] More preferably, the second adhesive layer 33 is an adhesive film, an epoxy layer, or an acrylic layer.

[0110] The nozzle component 3 has a nozzle 32, and the ink in the liquid storage component 2 is ejected from the nozzle 32.

[0111] The second adhesive layer 33 is used to connect the nozzle layer 31 to the liquid storage component 2; at the same time, the second adhesive layer 33 can also seal the nozzle layer 31 and the cavity wall 22, reducing the possibility of ink leakage from the nozzle layer 31.

[0112] The second adhesive layer 33 is completely covered on the nozzle layer 31. On the one hand, the second adhesive layer 33 is located inside the pressure chamber 21, so it is in direct contact with the ink. On the other hand, the second adhesive layer 33 isolates the ink from the nozzle layer 31, reducing the corrosiveness of the ink to the nozzle layer 31.

[0113] On the other hand, the second adhesive layer 33 is used to bond the nozzle layer 31 and the cavity wall 22 together. When applying the second adhesive layer 33, it is directly applied to the nozzle layer 31, and then the cavity wall 22 is directly applied to the second adhesive layer 33, thus achieving bonding between the cavity wall 22 and the second adhesive layer 33. Directly covering the nozzle layer 31 with the second adhesive layer 33 is easier to process, especially compared to the process of only partially applying the second adhesive layer 33 at the connection between the nozzle layer 31 and the cavity wall 22. Completely covering the second adhesive layer 33 is faster, simpler, and easier to control in terms of precision, thus improving the processing efficiency of the second adhesive layer 33.

[0114] The thickness of the nozzle layer 31 is 0.005 to 0.1 mm; preferably, the thickness of the nozzle layer 31 is 0.01 to 0.05 mm.

[0115] Specifically, the thickness of the nozzle layer 31 is: 0.005mm, 0.006mm, 0.007mm, 0.008mm, 0.009mm, 0.01mm, 0.015mm, 0.02mm, 0.025mm, 0.03mm, 0.035mm, 0.04mm, 0.045mm, 0.05mm, 0.055mm, 0.06mm, 0.065mm, 0.07mm, 0.075mm, 0.08mm, 0.086mm, 0.09mm, 0.095mm, 0.1mm.

[0116] In summary, this application provides a printhead with an isolation groove 11 formed on the piezoelectric ceramic 1. The isolation groove 11 isolates the vibration zone of the piezoelectric ceramic 1. When the piezoelectric ceramic 1 is energized, the vibration zone vibrates, and the mechanical crosstalk generated by the vibration zone is isolated by the isolation groove 11, thereby reducing mechanical crosstalk between adjacent vibration zones and improving the printing accuracy of the printhead. Furthermore, by placing the isolation groove 11 on the outside of the piezoelectric ceramic 1 or filling the inside of the isolation groove 11 with a filler, the piezoelectric ceramic 1 can be sealed to the cavity wall 22, improving the connection strength and sealing performance between the piezoelectric ceramic 1 and the cavity wall 22.

[0117] Furthermore, in this application, both the cavity wall 22 and the nozzle layer 31 are made of metal, which has extremely high wear resistance and hardness, thereby greatly improving the overall strength of the printhead. This results in a longer service life for the printhead.

[0118] Example 1

[0119] This application provides a printhead with an isolation groove 11 formed on the piezoelectric ceramic 1, thereby reducing mechanical crosstalk of the piezoelectric ceramic 1 on adjacent pressure chambers 21.

[0120] The piezoelectric ceramic 1 is 70 mm long, 10 mm wide, and 0.2 mm thick. The first adhesive layer 13 is made of 0.05 mm thick organic material.

[0121] The cavity wall 22 has a thickness of 0.2 mm and is made of stainless steel, with a protective layer of iron nitride on it. The pressure chamber 21 is a chamber with a length of 8 mm, a width of 0.5 mm, and a thickness of 0.2 mm.

[0122] The nozzle layer 31 is a stainless steel layer with a thickness of 0.05mm, and the nozzle 32 is a circular hole with a diameter of 0.05mm.

[0123] The second adhesive layer 33 is an epoxy resin adhesive layer. It is used to fix the cavity wall 22 to the nozzle layer 31.

[0124] The isolation groove 11 is formed on the upper end face of the piezoelectric ceramic 1;

[0125] The depth of the isolation groove 11 opened on the piezoelectric ceramic 1 is 20% of the total thickness of the piezoelectric ceramic 1.

[0126] The printing liquid used in the printhead is furan resin.

[0127] Example 2

[0128] Except for the opening of the isolation groove 11, which is different from the structure in Embodiment 1, the rest of the structure and materials are the same as those in Embodiment 1.

[0129] The isolation groove 11 is formed on the upper end face of the piezoelectric ceramic 1;

[0130] The depth of the isolation groove 11 formed on the piezoelectric ceramic 1 is 50% of the total thickness of the piezoelectric ceramic 1;

[0131] Example 3

[0132] Except for the opening of the isolation groove 11, which is different from the structure in Embodiment 1, the rest of the structure and materials are the same as those in Embodiment 1.

[0133] The isolation groove 11 is formed on the lower end face of the piezoelectric ceramic 1;

[0134] The depth of the isolation groove 11 formed on the piezoelectric ceramic 1 is 20% of the total thickness of the piezoelectric ceramic 1;

[0135] Example 4

[0136] Except for the opening of the isolation groove 11, which is different from the structure in Embodiment 1, the rest of the structure and materials are the same as those in Embodiment 1.

[0137] The isolation groove 11 is formed on the lower end face of the piezoelectric ceramic 1;

[0138] The depth of the isolation groove 11 formed on the piezoelectric ceramic 1 is 50% of the total thickness of the piezoelectric ceramic 1; Comparative Example

[0139] Except for the absence of the isolation groove 11, the structure and materials of this comparative example are the same as those in Example 1.

[0140] The printheads in Examples 1-4 and the comparative examples were tested for printing, and the operating status of the printheads was recorded.

[0141] Table 1 shows the working status of the printhead in Examples 1-4.

[0142] Example Isolation trench Printing status Example 1 20% of the top surface It can increase the effective injection frequency to 16K Example 2 50% of the top surface It can increase the effective injection frequency to 21K Example 3 20% of the lower end face It can increase the effective injection frequency to 12K. Example 4 50% of the lower end face It can increase the effective injection frequency to 14K

[0143] Table 2. Droplet size variation with jetting frequency (unit: picoliter)

[0144] 2K 4k 6k 8K 10K 12K 14K 16K 18K 20K 22K Example 1 65.4 66.8 68.2 70.6 72.1 76.8 77.8 78.6 60 Example 2 68.2 70.3 72.2 73 75.3 76.1 78.2 78.5 79.6 82.5 80 Example 3 66.2 68.6 73.8 74.2 74.6 75 48 Example 4 64.3 64.6 66.8 68.3 73.9 76.5 77 52 Comparative Example 62.3 63.8 67.5 68.8 69.6 69 51

[0145] Note: The jetting frequency is the ignition frequency; it can also be called the printing frequency.

[0146] As can be seen from Examples 1-4 and the Comparative Example, in the Comparative Example, the droplet size decreases as the ejection frequency increases after reaching 10 kHz. Examples 1-4 all show an increase compared to the Comparative Example, as shown in Table 1 above. Specifically, when an isolation groove is formed on the upper surface of the piezoelectric ceramic, and the depth of the isolation groove is 50% of the total thickness of the piezoelectric ceramic 1, the ejection frequency of the printhead can be increased to 21 kHz. Furthermore, a higher firing frequency can eject more ink, increasing the printhead's printing speed and efficiency.

[0147] Example 5

[0148] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of adhesive film. The adhesive film is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the adhesive film is 0.02 mm.

[0149] In this embodiment, the adhesive film is an F806P EVA adhesive film.

[0150] Example 6

[0151] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of adhesive film. The adhesive film is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the adhesive film is 0.045 mm.

[0152] In this embodiment, the adhesive film is an F806P EVA adhesive film.

[0153] Example 7

[0154] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of epoxy resin. Epoxy resin is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the epoxy resin is 0.01 mm.

[0155] Example 8

[0156] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of epoxy resin. Epoxy resin is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the epoxy resin is 0.02 mm.

[0157] Example 9

[0158] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of acrylic acid. Acrylic acid is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the acrylic acid is 0.02 mm.

[0159] Example 10

[0160] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the second adhesive layer 33 is made of acrylic acid. Acrylic acid is used to connect the cavity wall 22 to the nozzle layer 31. The thickness of the acrylic acid is 0.03 mm.

[0161] Example 11

[0162] The structure in this embodiment is exactly the same as that in Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is silicone (a conventional adhesive). The thickness of the adhesive is 0.02 mm.

[0163] The bonding effect of different second adhesive layers 33 on the cavity wall 22 (surface material is alumina) and the nozzle layer 31 (surface material is stainless steel) in Examples 5 to 11. The connection strength refers to the tensile strength.

[0164]

[0165]

[0166] As can be seen from Examples 5 to 11, when the second adhesive layer is epoxy resin or acrylic, the connection strength between the cavity wall and the nozzle layer is significantly increased compared to conventional silicone adhesive, reducing the possibility of the nozzle layer detaching from the cavity wall and improving the stability of the printhead.

[0167] Acrylic acid, due to its stable chemical properties that make it difficult for it to react with the ink inside the printhead, can significantly improve the lifespan of the printhead when used to connect the cavity wall to the nozzle layer.

[0168] When the second adhesive layer is a film, the connection strength between the cavity wall and the nozzle layer is significantly improved. It also boasts an extremely long service life. Compared to conventional silicone bonding, this represents a significant advancement and a substantial performance improvement.

[0169] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A printhead, characterized by, The ink storage member, the driving member and the nozzle member are arranged on both sides of the ink storage member, and the driving member can make the ink in the ink storage member be sprayed from the nozzle member; The driving member comprises a piezoelectric ceramic, and a separation part is arranged on the piezoelectric ceramic and separates the piezoelectric ceramic into parts suitable for the ink storage member; The separation part is a separation groove arranged on the piezoelectric ceramic.

2. The printhead of claim 1, wherein, The ink storage member comprises a plurality of independent pressure cavities, the ink is stored in the pressure cavities, the piezoelectric ceramic covers one end of the pressure cavities, and the separation groove is arranged between two adjacent pressure cavities.

3. The printhead of claim 2, wherein, The ink storage member comprises cavity walls forming the pressure cavities, the cavity walls are arranged in plurality, the cavity walls are connected with the piezoelectric ceramic, and the separation groove is arranged at the connection position of the cavity walls and the piezoelectric ceramic.

4. The printhead of claim 3, wherein, The piezoelectric ceramic comprises vibration zones corresponding to the pressure cavities, the vibration zones are arranged at one end of the pressure cavities and seal the pressure cavities, and the separation groove is arranged between two adjacent vibration zones.

5. The printhead of claim 1, wherein, The separation groove is arranged on the side of the piezoelectric ceramic close to the ink storage member. Alternatively, the separation groove is arranged on the side of the piezoelectric ceramic away from the ink storage member.

6. The printhead according to any one of claims 1 to 5, wherein, The separation groove is filled with a separation agent.

7. The printhead of claim 6, wherein, A first adhesive layer is arranged between the driving member and the ink storage member.

8. The printhead of claim 7, wherein, The first adhesive layer and the separation agent are made of the same material.

9. The printhead according to any one of claims 1-5, wherein, The ink storage member comprises cavity walls, and the cavity walls are made of metal.

10. The printhead of claim 9, wherein, The cavity walls are made of stainless steel or aluminum alloy.

11. The printhead of claim 10, wherein, A protective layer is arranged on the cavity walls.

12. The printhead of claim 11, wherein, The protective layer is an aluminum alloy layer.

13. The printhead of claim 11, wherein, The protective layer is an aluminum oxide layer.

14. The printhead of claim 11, wherein, When the cavity walls are made of aluminum alloy, the protective layer is an aluminum alloy layer.

15. The printhead of claim 10, wherein, A protective layer is arranged on the cavity walls.

16. The printhead of claim 15, wherein, The protective layer is a nitriding layer.

17. The printhead of claim 15, wherein, The protective layer is a nitriding iron layer.

18. The printhead of claim 15, wherein, The protective layer is a nitriding stainless steel layer.

19. The printhead of claim 15, wherein, When the cavity walls are made of stainless steel, the protective layer is a nitriding layer.

20. The printhead of any one of claims 1-5, wherein, The nozzle member comprises a nozzle layer, and a plurality of nozzles corresponding to the ink storage member are arranged on the nozzle layer.

21. The printhead of claim 20, wherein, The nozzle layer is made of metal.

22. The printhead of claim 21, wherein, The nozzle layer is made of stainless steel or nickel alloy.

23. The printhead of claim 20, wherein, A second adhesive layer is arranged between the nozzle member and the ink storage member, and the second adhesive layer is used for connecting the nozzle member and the ink storage member.

24. The printhead of claim 23, wherein, The second adhesive layer is arranged between the nozzle layer and the cavity walls.

25. The printhead of claim 24, wherein, The second adhesive layer covers the nozzle layer.

26. The printhead of claim 25, wherein, The second adhesive layer is a glue film, an epoxy layer or an acrylic layer.

Images