A method and apparatus for conditioning a gravure printing cylinder for security printing
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIAOZUO YINJINDA PACKAGING CO LTD
- Filing Date
- 2025-07-30
- Publication Date
- 2026-08-07
AI Technical Summary
[0003]但是凹版印刷也存在以下问题，就是制版结束后图案难以修改，需要重新制版，这就导致了在防伪印刷的时候就留下了隐患
[0015] The beneficial effects of this invention are as follows: If the area requiring adjustment is at the end of a cell, wax filler can be placed on one side of that location, forming an adjustment section between the wax filler and the end of the cell. If the area requiring adjustment is in the middle of a cell, wax filler can be placed on both sides of that location, forming an adjustment section between the two wax fillers. To prevent the etching solution from corroding the sidewalls of the cell, wax solution is sprayed onto the entire adjustment section to form an anti-corrosion wax layer on both the bottom and sidewalls of the adjustment section. Then, the wax layer on the bottom wall of the adjustment section is melted by the heating wire on the wax suction tube and sucked away from the cell. The etching solution is injected into the adjustment section to etch the bottom wall of the adjustment section. Finally, all the wax residue on the printing roller is washed away with hot water. During subsequent printing, this trimmed section is more recessed than the surrounding cells, storing deeper and more ink. After printing, this area forms a raised portion, creating an anti-counterfeiting feature. A series of continuous raised portions or multiple dispersed raised portions can be designed to form this anti-counterfeiting feature, which is difficult to detect and imitate. Even if detected and imitated, the imitator needs to create a new printing plate, especially an etching plate. Existing etching plates cannot allow for further localized adjustments to the pattern. However, the trimming method and device of this application can perform adjustments at any time in many places on the printing roller. Imitators would need to detect and recreate the plate, which is very costly, thus achieving a better anti-counterfeiting effect.
Smart Images
Figure CN120588620B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of gravure printing technology, and specifically to a method and apparatus for conditioning gravure printing rollers used in anti-counterfeiting printing. Background Technology
[0002] Gravure printing is a printing method that holds an extremely important position in the printing, packaging, and graphic publishing industries due to its advantages such as thick ink layers, vibrant colors, high saturation, high plate durability, stable print quality, and fast printing speed. Gravure printing involves coating the entire surface of the printing plate cylinder with ink, then using a special doctor blade to remove the ink from the non-image areas, leaving only ink in the cells of the image areas. Under significant pressure, the ink is then transferred to the substrate surface to obtain the printed product.
[0003] However, gravure printing also has the following problems: the pattern is difficult to modify after the plate is made, requiring the plate to be made again. This creates a vulnerability in anti-counterfeiting printing. This type of anti-counterfeiting is easily detected and cracked, leading to the appearance of counterfeit products, and there is also a risk of leakage of information by the third party making the plate. Therefore, in order to improve the anti-counterfeiting effect, manufacturers need to trim the gravure printing rollers after the plate is made so that the printed pattern is different from the pattern made on the plate. Summary of the Invention
[0004] The purpose of this invention is to provide a method for trimming gravure printing rollers used in anti-counterfeiting printing to improve the anti-counterfeiting effect; at the same time, the purpose of this invention is also to provide a trimming device using the above-mentioned trimming method.
[0005] To achieve the above objectives, the present invention provides a method for conditioning a gravure printing roller for anti-counterfeiting printing, comprising the following steps: 1) Place wax filler on one or both sides of the mesh location where anti-counterfeiting is required. The wax filler is used to seal the mesh on the corresponding side, so that the mesh segment on the side of the wax filler or the mesh segment between two wax fillers forms a trimmed segment. 2) Spray an anti-corrosion wax layer into the trimmed section of step 1); 3) Insert a wax suction tube with a heating wire at the end into the trimming section in step 2). The heating wire melts the wax layer on the bottom wall of the trimming section and the wax suction tube sucks away the melted wax. 4) Inject the etching solution into the trimming section in step 3) to etch the bottom wall of the trimming section; 5) After the corrosion time is set, rinse the gravure printing roller with hot water at 50°C or higher to clean the wax filler and wax layer on it.
[0006] In step 5), after a certain period of corrosion, the corrosive liquid is removed and a new corrosive liquid is injected. This process is repeated more than twice until the desired corrosion effect is achieved.
[0007] A dressing device for implementing the above-mentioned dressing method according to the present invention adopts the following technical solution: A dressing device capable of implementing the above-mentioned dressing method includes a device frame for rotating and mounting the printing roller to be dressed. The device frame has a crossbeam located above the printing roller, the length direction of the crossbeam being parallel to the axial direction of the printing roller. Two or more dressing mechanisms are movably arranged on the crossbeam. Each dressing mechanism includes a lifting frame movably mounted on the crossbeam. An electric telescopic rod is provided on the lifting frame. A horizontal mounting plate is rotatably mounted on the movable end of the electric telescopic rod. A first gear is provided on the movable end. A second gear that drives the first gear and drives the second gear to rotate is provided on the horizontal mounting plate. The first drive motor; a horizontal mounting rod is rotatably mounted on the horizontal mounting plate, and a second drive motor is mounted on the horizontal mounting plate to drive the horizontal mounting rod to rotate. Two wax injection tubes are horizontally opposite each other on the horizontal mounting rod, which are used to inject wax filler on one or both sides of the mesh position where anti-counterfeiting is required, so that the mesh segment on one side of the wax filler or the mesh segment between the two wax fillers forms a trimmed section; the horizontal mounting plate is equipped with a wax spraying tube, a wax suction tube, and a liquid injection tube. The wax spraying tube is used to spray an anti-corrosion wax layer onto the bottom wall and side wall of the trimmed section. The lower end of the wax suction tube is equipped with a heating wire to melt the wax layer on the bottom wall of the trimmed section. The liquid injection tube is used to inject corrosive liquid into the mesh.
[0008] Each of the wax injection tubes is horizontally and movably mounted on a horizontal mounting rod, allowing for adjustment of the distance between them.
[0009] The horizontal mounting rod is provided with a downward-facing T-shaped guide groove. Two movable rods are mounted in the T-shaped guide groove for guidance and movement. The upper end of the movable rod has a threaded section, and a locking nut is provided on the threaded section. The lower end of each movable rod is provided with a pipe clamp for fixing the wax injection tube.
[0010] The upper end of the injection tube is provided with a Y-shaped connector. The first port of the upper end of the Y-shaped connector is used to connect to the aspirator, and the other port is used to connect to the injector.
[0011] A wax tank is provided on the horizontal mounting plate. The wax tank is connected to the wax spraying pipe through a first pipe, and to two wax injection pipes through a second pipe and a third pipe, respectively. Each of the first, second, and third pipes is equipped with an injection pump. Heating wires are provided on the wax tank, as well as on the first, second, and third pipes, to prevent the wax from solidifying.
[0012] The injection pump is equipped with a heating wire or is covered with an insulation layer.
[0013] A wax recovery tank is provided on the horizontal mounting plate. The wax recovery tank is connected to the wax suction pipe through a fourth pipe. An air duct is connected to the fourth pipe, and a fan is installed on the air duct. The air duct and the fourth pipe form a Venturi tube structure.
[0014] The crossbeam is provided with a T-slot, and the hoisting frame is provided with a bolt that is movably installed in the T-slot. The head of the bolt is located in the T-slot, and the shank of the bolt extends upward through the T-slot and is equipped with a locking nut.
[0015] The beneficial effects of this invention are as follows: If the area requiring adjustment is at the end of a cell, wax filler can be placed on one side of that location, forming an adjustment section between the wax filler and the end of the cell. If the area requiring adjustment is in the middle of a cell, wax filler can be placed on both sides of that location, forming an adjustment section between the two wax fillers. To prevent the etching solution from corroding the sidewalls of the cell, wax solution is sprayed onto the entire adjustment section to form an anti-corrosion wax layer on both the bottom and sidewalls of the adjustment section. Then, the wax layer on the bottom wall of the adjustment section is melted by the heating wire on the wax suction tube and sucked away from the cell. The etching solution is injected into the adjustment section to etch the bottom wall of the adjustment section. Finally, all the wax residue on the printing roller is washed away with hot water. During subsequent printing, this trimmed section is more recessed than the surrounding cells, storing deeper and more ink. After printing, this area forms a raised portion, creating an anti-counterfeiting feature. A series of continuous raised portions or multiple dispersed raised portions can be designed to form this anti-counterfeiting feature, which is difficult to detect and imitate. Even if detected and imitated, the imitator needs to create a new printing plate, especially an etching plate. Existing etching plates cannot allow for further localized adjustments to the pattern. However, the trimming method and device of this application can perform adjustments at any time in many places on the printing roller. Imitators would need to detect and recreate the plate, which is very costly, thus achieving a better anti-counterfeiting effect. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of one embodiment of a trimming device of the present invention; Figure 2 yes Figure 1 A magnified view of a section at point A in the middle; Figure 3 yes Figure 1 A structural diagram from another angle; Figure 4 yes Figure 3 A magnified view of a section at point B in the middle. Detailed Implementation
[0017] To facilitate understanding of the present invention, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.
[0018] It should be noted that, unless otherwise defined, the technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The use of "belonging" in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention.
[0019] A method for conditioning a gravure printing roller for anti-counterfeiting printing according to the present invention includes the following steps: 1) Place wax filler on one or both sides of the mesh location where anti-counterfeiting is required. The wax filler is used to seal the mesh on the corresponding side, so that the mesh segment on the side of the wax filler or the mesh segment between two wax fillers forms a trimmed segment.
[0020] In this step, if the area requiring trimming is at the end of a mesh cell, wax filler can be placed on one side of that location, forming a trimming section between the wax filler and the end of the mesh cell. If the area requiring trimming is in the middle of a mesh cell, wax filler can be placed on both sides of that location, forming a trimming section between the two wax fillers.
[0021] 2) Spray an anti-corrosion wax layer into the trimmed section of step 1).
[0022] Since it is difficult to spray a wax layer onto the opposite sidewalls of the trimming section separately, this step in this application results in wax being sprayed onto both the bottom and sidewalls of the trimming section, forming a wax layer.
[0023] 3) Insert a wax suction tube with a heating wire at the end into the trimming section in step 2). The heating wire melts the wax layer on the bottom wall of the trimming section and the wax suction tube sucks away the melted wax.
[0024] 4) Inject the corrosive liquid into the trimming section in step 3) to corrode the bottom wall of the trimming section.
[0025] In this step, the appropriate etching solution is selected based on the material of the printing roller.
[0026] 5) After the corrosion time is set, rinse the gravure printing roller with hot water at 50°C or higher to clean the wax filler and wax layer on it.
[0027] In this step, the etching time is set according to the required etching depth. The hot water temperature should be chosen just enough to melt the wax on the printing roller and then carry it away with the water flow, such as 80 degrees, 90 degrees, or 100 degrees Celsius. The appropriate hot water temperature is also selected based on the type of wax used.
[0028] In this step, since the amount of corrosive liquid injected is limited, if the corrosion effect cannot be achieved in one corrosion, the corrosive liquid will be removed after a certain period of corrosion, and new corrosive liquid will be injected again. This process will be repeated two or more times until the desired corrosion effect is achieved.
[0029] A dressing apparatus of the present invention for implementing the above-described dressing method for gravure printing rollers used in anti-counterfeiting printing, such as... Figures 1-4 As shown, the device includes a frame 1 for rotatably mounting the printing roller 2 to be repaired. The frame 1 is equipped with a power mechanism 3 that drives the printing roller 2 to rotate; the power mechanism 3 is an electric motor. The frame 1 has a driven shaft and a driving shaft, with the driving shaft connected to the electric motor. Both the driven shaft and the driving shaft are rotatably mounted on the frame. The roller shafts fixed at both ends of the printing roller 2 to be repaired are respectively connected to the driven shaft and the driving shaft via couplings. The rotation of the printing roller is driven by the electric motor to adjust the angle of rotation, ensuring that the cells to be repaired face upwards.
[0030] The frame 1 includes a base plate 28, vertical beams 29, and a top crossbeam 4. The printing roller 2 is rotatably mounted on two opposing vertical beams 29. The crossbeam 4 is located above the printing roller, and its length direction is parallel to the axis of the printing roller. During installation, a U-shaped mounting groove 31 is provided at the upper end of the vertical beam 29, and rectangular mounting blocks 30 are provided at both ends of the crossbeam 4. The rectangular mounting blocks 30 are fitted into the U-shaped mounting grooves 31, and the rectangular mounting blocks 30 and the U-shaped mounting grooves 31 are fixed together by connecting bolts 32 for easy installation and disassembly. Two or more trimming mechanisms 5 are movably mounted on the crossbeam 4. The number of trimming mechanisms 5 is equal to the number of patterns in a single row along the axis of the printing roller. Each trimming mechanism 5 includes a lifting frame 6 movably mounted on the crossbeam. A T-slot 7 is provided on the crossbeam 4, and a bolt is movably mounted on the lifting frame 6 in the T-slot 7. The head of the bolt is located in the T-slot, and the shank of the bolt extends upward through the T-slot and is equipped with a locking nut 8. After adjustment, each trimming mechanism is located directly above the corresponding printing roller section to be trimmed.
[0031] An electric telescopic rod 9 is installed on the hoisting frame 6. A horizontal mounting plate 10 is rotatably mounted on the movable end 11 of the electric telescopic rod 9. A first gear 12 is mounted on the movable end 11. A second gear 13, which meshes with the first gear, and a first drive motor 14, which drives the second gear, are mounted on the horizontal mounting plate 10. Power is transmitted between the first gear 12 and the second gear 13 through an intermediate gear 15. The intermediate gear allows for flexible adjustment of the positions of the second gear and the first drive motor, preventing interference between them. A horizontal mounting rod 16 is rotatably mounted on the horizontal mounting plate 10. A second drive motor 17, which drives the horizontal mounting rod, is mounted on the horizontal mounting plate. Two wax injection tubes 18 are horizontally opposite each other on the horizontal mounting rod. The wax injection tubes 18 are used to inject wax filler into one or both sides of the mesh area where anti-counterfeiting is required, so that the mesh section on the side with wax filler or the mesh section between two wax fillers forms a trimmed section. The horizontal mounting rod 16 is provided with a downward-facing T-shaped guide groove 28. Two movable rods 19 are mounted in the T-shaped guide groove for guidance and movement. The upper end of the movable rod has a threaded section, and a locking nut 29 is provided on the threaded section. The lower end of each movable rod is provided with a pipe clamp 20 for fixing the wax injection tube. The two movable wax injection tubes 18 can be adjusted to the required length, making them convenient to use.
[0032] The horizontal mounting plate 10 is equipped with a wax spraying pipe 21, a wax suction pipe 22, and a liquid injection pipe 23. The wax spraying pipe 21 is used to spray an anti-corrosion wax layer into the trimming section. The lower end of the wax suction pipe 22 is equipped with a heating wire to melt the wax layer on the bottom wall of the mesh cavity. The liquid injection pipe 23 is used to inject corrosive liquid into the mesh cavity. In this embodiment, the upper end of the liquid injection pipe 23 is equipped with a Y-shaped connector. The first port 24 of the upper end of the Y-shaped connector is used to connect to the suction device, and the other port 25 is used to connect to the injection device, which can realize the recovery of corrosive liquid. The horizontal mounting plate is equipped with a wax liquid tank 26. The wax liquid tank 26 is connected to the wax spraying pipe 21 through a first pipe, and connected to two wax injection pipes 18 through a second pipe and a third pipe, respectively. Each of the first, second, and third pipes is equipped with a liquid injection pump. Heating wires are installed on the wax liquid tank and on the first, second, and third pipes to prevent the wax liquid from solidifying. The injection pump is equipped with a heating wire or an insulation layer to prevent the wax from solidifying as it passes through. A wax recovery tank 27 is mounted on the horizontal mounting plate 10. The wax recovery tank is connected to the wax suction pipe 22 via a fourth pipe. An air duct is connected to the fourth pipe, and a fan is mounted on the air duct. The air duct and the fourth pipe form a Venturi tube structure. A heating wire is also installed on the fourth pipe to ensure that the wax can enter the wax storage tank and prevent it from solidifying on the pipe wall and causing blockage. The fan can also blow hot air.
[0033] In use, the printing roller to be repaired is mounted on the device frame and connected to the power mechanism. The power mechanism rotates the printing roller to adjust its position, so that the cells to be repaired in one row of patterns are directly above. Then, the position of the repair mechanism is adjusted so that it corresponds one-to-one with the cells to be repaired below. Next, the positions of the two wax injection tubes on all repair mechanisms are adjusted so that the distance between the two wax injection tubes equals the length of the cell to be repaired. Wax is injected into the cell section below through the two wax injection tubes in conjunction with the electric push rod. The wax instantly solidifies in the cell, forming a wax filler. The cell section between the two wax fillers forms the repair section. If the cell section to be repaired is located at the end, only one wax injection tube can be used; in this case, the repair section is formed between the wax filler and the end of the cell. Then, rotate the horizontal mounting plate to position the wax spray tube above the trimming section. Since the cell cross-section is typically T-shaped to ensure ink is smoothly carried out by the printed material during plate making, the wax spray tube, in conjunction with the electric actuator, can spray wax onto both the bottom and side walls of the trimming section to form an anti-corrosion layer. Next, rotate the horizontal mounting plate to position the wax suction tube above the trimming section, and in conjunction with the electric actuator, insert the heating wire at the lower end of the suction tube into the trimming section. The heating wire can be in a wavy or straight shape. The heating wire melts the wax at the bottom of the trimming section, which is then drawn into the suction tube under negative pressure. Finally, rotate the horizontal mounting plate to position the injection tube above the trimming section, and in conjunction with the electric actuator, inject etchant into the trimming section through the injection tube to etch the bottom wall of the trimming section. The etchant is then recovered through the injection tube. Finally, place a water tank on the base plate below the printing roller, pour hot water onto the printing roller to melt all the wax on it and rinse off any remaining corrosive liquid, then let it air dry or bake it dry.
[0034] In the foregoing description of this specification, unless otherwise expressly specified and limited, the terms "fixed," "installed," "connected," or "linked" should be interpreted broadly. For example, the term "linked" can refer to 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 an indirect connection through an intermediate medium; or it can refer to the internal communication of two components or the interaction between two components. Therefore, unless otherwise expressly limited in this specification, those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0035] Based on the above description in this specification, those skilled in the art will also understand that terms used, such as "upper," "lower," "front," "rear," "left," "right," "length," "width," "thickness," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," "center," "longitudinal," "transverse," "clockwise," or "counterclockwise," are terms indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings of this specification. They are only for the purpose of facilitating the explanation of the present invention and simplifying the description, and do not explicitly or implicitly suggest that the device or element involved must have the specific orientation, or be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms should not be understood or interpreted as limitations on the present invention.
[0036] Furthermore, the terms "first" or "second," etc., used in this specification to refer to numbers or ordinal numbers are for descriptive purposes only and should not be construed as indicating, explicitly or implicitly, relative importance or specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this specification, "a plurality of" means at least two, such as two, three, or more, unless otherwise explicitly specified.
[0037] In other embodiments of the present invention, in order to facilitate the adjustment of the positions of the wax suction tube, the wax spraying tube, and the liquid injection tube, the installation method of the liquid injection tube can be referenced. An installation rod is rotatably set on a horizontal mounting plate, and a drive motor for driving the installation rod to rotate is set on the horizontal mounting plate. The installation rod and the drive motor are one-to-one and there are three of them, which are respectively set to correspond to the wax suction tube, the wax spraying tube, and the liquid injection tube. At this time, each installation rod is provided with a T-shaped groove, and a movable rod is guided and moved in each T-shaped groove. The upper end of the movable rod has a threaded section, and a locking nut is equipped on the threaded section. The lower end of each movable rod is provided with a tube clamp for fixing the wax suction tube, the wax spraying tube, and the liquid injection tube.
Claims
1. A dressing device for gravure printing rollers used in anti-counterfeiting printing, characterized in that: The device includes a frame for rotating and mounting a printing roller to be dressed. The frame has a crossbeam located above the printing roller, the length of which is parallel to the axis of the printing roller. Two or more dressing mechanisms are movably mounted on the crossbeam. Each dressing mechanism includes a lifting frame movably mounted on the crossbeam. An electric telescopic rod is mounted on the lifting frame. A horizontal mounting plate is rotatably mounted on the movable end of the electric telescopic rod. A first gear is mounted on the movable end. A second gear, which drives the first gear, and a first drive motor, which drives the second gear, are mounted on the horizontal mounting plate. A horizontal mounting rod is rotatably mounted on the horizontal mounting plate, and a drive motor for rotating the second gear is mounted on the horizontal mounting plate. The second drive motor rotates the rod. Two wax injection tubes are horizontally mounted opposite each other on the horizontal mounting rod. These tubes are used to inject wax filler into one or both sides of the mesh area where anti-counterfeiting is required, so that the mesh segment on one side of the wax filler or the mesh segment between the two wax fillers forms a trimmed section. The horizontal mounting plate is equipped with a wax spraying tube, a wax suction tube, and a liquid injection tube. The wax spraying tube is used to spray an anti-corrosion wax layer onto the bottom and side walls of the trimmed section. The lower end of the wax suction tube is equipped with a heating wire to melt the wax layer on the bottom wall of the trimmed section. The liquid injection tube is used to inject corrosive liquid into the mesh. All the wax injection tubes are horizontally movable on the horizontal mounting rod, allowing for adjustment of the distance between them.
2. The trimming device according to claim 1, characterized in that: The horizontal mounting rod is provided with a downward-facing T-shaped guide groove. Two movable rods are mounted in the T-shaped guide groove for guidance and movement. The upper end of the movable rod has a threaded section, and a locking nut is provided on the threaded section. The lower end of each movable rod is provided with a pipe clamp for fixing the wax injection tube.
3. The trimming device according to claim 1, characterized in that: The upper end of the injection tube is provided with a Y-shaped connector. The first port of the upper end of the Y-shaped connector is used to connect to the aspirator, and the other port is used to connect to the injector.
4. The trimming device according to claim 1, characterized in that: A wax tank is provided on the horizontal mounting plate. The wax tank is connected to the wax spraying pipe through a first pipe, and to two wax injection pipes through a second pipe and a third pipe, respectively. Each of the first, second, and third pipes is equipped with an injection pump. Heating wires are provided on the wax tank, as well as on the first, second, and third pipes, to prevent the wax from solidifying.
5. The trimming device according to claim 4, characterized in that: The injection pump is equipped with a heating wire or is covered with an insulation layer.
6. The trimming device according to claim 1, characterized in that: A wax recovery tank is provided on the horizontal mounting plate. The wax recovery tank is connected to the wax suction pipe through a fourth pipe. An air duct is connected to the fourth pipe, and a fan is installed on the air duct. The air duct and the fourth pipe form a Venturi tube structure.
7. The trimming device according to claim 6, characterized in that: The crossbeam is provided with a T-slot, and the hoisting frame is provided with a bolt that is movably installed in the T-slot. The head of the bolt is located in the T-slot, and the shank of the bolt extends upward through the T-slot and is equipped with a locking nut.
Citation Information
Patent Citations
Method for making large multi-gradation intaglio plate floral roller
CN1161906A