Imprinting method and control device for a paper imprinting apparatus

Abstract

The application relates to a stamping method, a control device and a paper stamping equipment, relates to the technical field of printing, and the stamping method comprises the following steps: coating: first passing paper through a first coating assembly, so that the first coating assembly coats the paper with a water-retaining agent, and then passing the paper through a second coating assembly, so that the second coating assembly coats the paper coated with the water-retaining agent with an imaging layer; stamping: passing the paper coated with the imaging layer through a stamping assembly and a light curing assembly, so that the stamping assembly can stamp the imaging layer of the paper to form an image, and the light curing assembly can light-cure the stamped image to form a shape. By coating a water-retaining agent primer, the problem of absorption and penetration of the imaging layer paint by the paper can be solved. The composition ratio of each region of the imaging layer remains consistent, uniform curing can be realized in the light curing process, and the problem of incomplete local curing leading to incomplete image structure can be avoided.

Description

Technical Field

[0001] This application relates to the field of printing technology, and in particular to an imprinting method, control device, and paper imprinting equipment. Background Technology

[0002] Existing paper embossing equipment typically involves coating a photocurable imaging layer directly onto the paper surface using a coating mechanism, then imprinting the desired fine image onto this layer using an embossing mechanism, and finally curing the imaging layer using a photocuring component to complete the entire embossing process. However, because paper is a porous and absorbent material with numerous micropores and capillary channels on its surface and inside, when the coating of the photocurable imaging layer is directly applied to the paper surface, the paper quickly absorbs the solvent or active monomers from the coating. This causes a sharp decrease in the leveling properties of the imaging layer on the paper surface, preventing the coating from forming a uniform and smooth film, resulting in surface defects such as pinholes and orange peel texture. At the same time, due to the uneven absorption of solvents or monomers, the concentration of photocurable components in some areas of the imaging layer is insufficient, causing incomplete local curing. Ultimately, this results in incomplete embossed image structure, poor clarity, and image quality that fails to meet the requirements of fine embossing. Summary of the Invention

[0003] To address the problem of low efficiency in manual screw tightening, this application provides an embossing method.

[0004] Firstly, the imprinting method provided in this application adopts the following technical solution: An imprinting method is used in a paper imprinting apparatus, the paper imprinting apparatus including a coating mechanism and an imprinting mechanism, the coating mechanism including a first coating component and a second coating component, the imprinting mechanism including an imprinting component and a photocuring component disposed on the imprinting component, the imprinting method comprising: Coating: The paper is first passed through the first coating component, where the first coating component coats the paper with a water-retaining agent, and then passed through the second coating component, where the second coating component coats the paper coated with the water-retaining agent with an imaging layer. Imprinting: Paper coated with the imaging layer is passed through the imprinting assembly and the photocuring assembly, so that the imprinting assembly can imprint an image from the imaging layer of the paper, and the photocuring assembly can photocur the imprinted image to form a solid shape.

[0005] Optionally, the paper printing apparatus further includes an oven, the oven comprising a component disposed between the first coating assembly and the second coating assembly; The step of first passing the paper through the first coating assembly to coat the paper with a water-retaining agent further includes: The paper passes through the first conveying structure of the oven, enabling the oven to bake the paper coated with a water-retaining agent.

[0006] Optionally, the paper imprinting equipment may further include a corona assembly; After the paper passes through the oven, allowing the oven to bake the paper coated with a water-retaining agent, the process further includes: The paper passes through the corona electrode assembly, which enables the corona electrode assembly to perform corona treatment on the baked paper.

[0007] Optionally, the paper imprinting apparatus further includes an oven, which is disposed between the second coating assembly and the imprinting assembly; Before the paper coated with the imaging layer passes through the imprinting assembly and the photocuring assembly, the process further includes: The paper passes through the second conveying structure of the oven, enabling the oven to bake the paper coated with the imaging layer.

[0008] Optionally, the coating amount of the imaging layer is 3-10 g / m2.

[0009] Optionally, the material of the imaging layer includes at least one of varnish, ink, or clear varnish.

[0010] Optionally, the water-retaining agent includes water-based acrylic smooth water-retaining coatings, water-based polyurethane smooth water-retaining coatings, or water-based polyvinyl alcohol smooth water-retaining coatings.

[0011] Secondly, the control device provided in this application adopts the following technical solution: A control device includes a memory and a processor, and a control program for a paper printing apparatus stored in the memory and executable on the processor, the control device being configured to implement the steps of the printing method of the paper printing apparatus.

[0012] Thirdly, the paper imprinting equipment provided in this application adopts the following technical solution: A paper stamping device includes: The frame is equipped with an unwinding roller and a rewinding roller. The unwinding roller is used to feed the paper, and the rewinding roller is used to rewind the printed paper. The coating mechanism includes a first coating assembly and a second coating assembly disposed on the frame. The first coating assembly is used to coat the paper released from the unwinding roll with a water-retaining agent, and the second coating assembly is used to coat the paper coated with the water-retaining agent with an imaging layer; and... An imprinting mechanism includes an imprinting assembly and a photocuring assembly disposed on the frame. The imprinting assembly is used to imprint paper coated with an imaging layer to form an image on the imaging layer of the paper. The photocuring assembly is used to irradiate the imprinted paper to cure the imaging layer of the paper. A control device is electrically connected to the coating mechanism and the printing mechanism to control the operation of the coating mechanism and the printing mechanism.

[0013] In this technical solution, a water-retaining agent is first coated onto the paper surface. This agent penetrates the pores and capillary channels of the paper surface, forming a continuous and dense closed layer. This blocks the absorption channels of solvents and active monomers in the subsequent imaging layer coating, allowing the imaging layer coating applied by the second coating component to maintain good flow and leveling on the surface of the water-retaining agent layer. This results in a uniformly thick and smooth imaging film layer on the paper surface. When the paper passes through the imprinting component, the uniform and smooth imaging layer can fully adhere to the imprinting plate under pressure, accurately replicating the micro-nano structures on the plate. Subsequently, the photocuring component instantly cures the imaging layer, solidifying and shaping the fine image structure within it. Thus, by applying a water-retaining agent undercoat, the problem of paper absorption and penetration of the imaging layer coating is solved. Because the photocurable components in the imaging layer are no longer unevenly absorbed by the paper, the composition ratio of each area of ​​the imaging layer remains consistent, achieving comprehensive and uniform curing during the photocuring process and avoiding image structure defects caused by incomplete local curing. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the paper printing equipment provided in this application; Figure 2 yes Figure 1 A side view of the paper printing equipment; Figure 3 yes Figure 2 A magnified view of a portion of point A in the middle; Figure 4 yes Figure 1 A three-dimensional structural diagram of the intermediate coating mechanism from one angle; Figure 5 yes Figure 1 A three-dimensional structural diagram of the intermediate coating mechanism from another angle; Figure 6 yes Figure 5 A magnified view of a portion of point B in the middle; Figure 7 yes Figure 1 A three-dimensional structural diagram of the embossing mechanism at one angle; Figure 8 yes Figure 1 A three-dimensional structural diagram of the embossing mechanism from another angle; Figure 9 yes Figure 1 A three-dimensional structural diagram of the tensioning component in the diagram; Figure 10 yes Figure 1 A cross-sectional schematic diagram of the impression roller in the impression mechanism; Figure 11 This is a schematic diagram of the control device of the paper printing equipment according to an embodiment of the present invention; Figure 12 This is a schematic diagram of the first process of the paper imprinting method provided by the present invention.

[0015] Explanation of reference numerals in the attached figures: 100. Imprinting methods; 100. Paper imprinting equipment; 1. Frame; 11. Coating rack; 12. Imprinting rack; 2. Coating mechanism; 2a. First coating assembly; 2b. Second coating assembly; 21. Coating structure; 211. Coating roller; 212. Coating pressure roller; 213. Coating seat; 214. First linear drive structure; 215. Coating motor; 22. Doctor blade structure; 221. Coating doctor blade; 222. First coating mounting roller; 223. First coating mounting seat; 224. Second coating mounting seat; 225. Doctor blade drive Structure; 2251, First worm gear structure; 2252, First operating wheel; 23, Material trough structure; 231, Coating trough; 232, Second coating mounting roller; 233, First coating transmission structure; 234, Material trough drive structure; 2341, Second worm gear structure; 2342, Second operating wheel; 24, Guide structure; 241, Guide roller; 242, Guide swing arm; 243, Third worm gear structure; 3. Imprinting mechanism; 31. Imprinting assembly; 311. Imprinting roller; 3111. Roller body; 3112. Transparent plate cylinder; 312. Imprinting pressure roller; 313. Third linear drive structure; 314. Imprinting motor; 315. Peeling roller; 32. Photocuring assembly; 33. Tensioning assembly; 331. Tensioning mounting roller; 332. Tensioning adjusting roller; 333. Tensioning connecting arm; 334. Tensioning drive structure; 3341. Tensioning drive arm; 3342. Fourth linear drive structure; 34. Illumination assembly; 4. Unwinding roller; 5. Rewinding roller; 51. Rewinding motor; 6. Oven; 61. First conveying structure; 611. First conveying roller; 62. Second conveying structure; 621. Second conveying roller; 7. Corona discharge assembly. Detailed Implementation

[0016] The following is in conjunction with the appendix Figure 1 -Appendix Figure 12 This application will be described in further detail below.

[0017] In one embodiment of this application, a paper imprinting apparatus 100 is used to imprint images. The paper imprinting apparatus 100 includes a frame 1, a coating mechanism 2, and an imprinting mechanism 3. The frame 1 is provided with an unwinding roller 4 and a winding roller 5. The unwinding roller 4 is used to unload paper, and the winding roller 5 is used to wind up the imprinted paper. The coating mechanism 2 includes a first coating component 2a and a second coating component 2b disposed on the frame 1. The first coating component 2a is used to coat the paper unloaded by the unwinding roller 4 with a water-retaining agent, and the second coating component 2b is used to coat the paper coated with the water-retaining agent. The paper is coated with an imaging layer. The imprinting mechanism 3 includes an imprinting component 31 and a photocuring component 32 mounted on the frame 1. The imprinting component 31 is used to imprint the paper coated with the imaging layer so that the imaging layer of the paper forms an image. The photocuring component 32 is used to irradiate the imprinted paper so that the imaging layer of the paper is cured. The paper released from the unwinding roller 4 is coated with a water-retaining agent by the first coating component 2a and an imaging layer by the second coating component 2b. Then, the image is imprinted by the imprinting component 31 and finally cured by the photocuring component 32.

[0018] It should be noted that the frame 1 is the supporting frame of the entire equipment, on which an unwinding roller 4 and a winding roller 5 are mounted. The unwinding roller 4 is used to mount and release the paper roll to be processed, and the winding roller 5 is used to rewind the printed paper into a roll. The coating mechanism 2 includes a first coating component 2a and a second coating component 2b. The first coating component 2a is used to coat the paper surface with a water-retaining agent. The water-retaining agent is a pretreatment liquid that can improve the wettability and water retention of the paper surface. Its function is to adjust the moisture content and surface state of the paper so that the paper maintains its original moisture content in subsequent processes. Furthermore, there are various types of water-retaining agents, such as water-based acrylic smoothing water-retaining coatings, water-based polyurethane smoothing water-retaining coatings, or water-based polyvinyl alcohol smoothing water-retaining coatings, etc., as long as they can keep the moisture content of the paper unchanged. The embodiments of this application do not limit this. The second coating component 2b is used to coat a photocurable imaging layer onto the surface of paper that has already been coated with a water-retaining agent. The imaging layer is typically formulated from components such as UV-curable resin, photoinitiator, and reactive diluent monomers. The imprinting mechanism 3 includes an imprinting component 31 and a photocuring component 32. The imprinting component 31 is used to imprint a fine image with a micro-nano structure onto the surface of the imaging layer. The photocuring component 32 typically uses an ultraviolet light source to irradiate the imprinted imaging layer to crosslink and cure it.

[0019] It should also be noted that after the paper is released from the unwinding roller 4, it first passes through the first coating component 2a. The first coating component 2a coats a layer of water-retaining agent on the paper surface. The water-retaining agent penetrates into the micropores and capillary channels of the paper surface and forms a dense sealing film layer on the paper surface. This film layer can effectively prevent the solvent or active monomer in the subsequently coated imaging layer from penetrating and diffusing into the paper. After the water-retaining agent treatment is completed, the paper continues to pass through the second coating component 2b. The second coating component 2b coats the photocurable imaging layer on the paper surface that has been sealed by the water-retaining agent. Since the porous structure of the paper surface has been filled and sealed by the water-retaining agent, the solvent and active monomer in the imaging layer will not be quickly absorbed by the paper. The imaging layer can maintain a sufficiently wet state and good flowability on the paper surface, thereby achieving uniform spreading and full leveling. The coated paper then enters the imprinting assembly 31, which transfers the micro-nano structure pattern on the template into the imaging layer to form a fine structured image. Finally, after being irradiated by the photocuring assembly 32, the photocuring components in the imaging layer undergo a cross-linking polymerization reaction under the action of ultraviolet light, so that the imprinted image is permanently fixed.

[0020] In this embodiment, by setting the first coating component 2a, a water-retaining agent intermediate layer can be introduced between the paper and the imaging layer. This allows the solvent and active monomers in the imaging layer to be effectively retained on the paper surface, and the imaging layer can naturally level under sufficient wetting conditions. This eliminates surface defects such as poor leveling, pinholes, and orange peel texture caused by rapid absorption of solvent. It also ensures that the concentration of photocurable components in each area of ​​the imaging layer is uniform and consistent, avoiding the problem of incomplete local curing. This results in a complete and clear image structure after imprinting. Thus, it solves the problem that when the existing paper imprinting equipment 100 directly coats the photocurable imaging layer on the paper, the paper absorbs the solvent or active monomers in the imaging layer, resulting in poor leveling of the imaging layer, pinholes, orange peel texture, and incomplete local curing, which seriously affects the quality of the imprinted image on the paper surface.

[0021] In one embodiment of this application, the paper imprinting apparatus 100 further includes an oven 6 disposed between the first coating component 2a and the second coating component 2b and / or between the second coating component 2b and the imprinting mechanism 3, for drying the paper coated with a water-retaining agent or an imaging layer.

[0022] It is understood that the oven 6 is typically equipped with an electric heating element or a hot air circulation system, capable of applying uniform heat to the paper passing through it. When the oven 6 is located between the first coating assembly 2a and the second coating assembly 2b, it is used to dry paper coated with a water-retaining agent; when the oven 6 is located between the second coating assembly 2b and the printing mechanism 3, it is used to dry paper coated with an imaging layer. Furthermore, the oven 6 can be arranged in various ways, either in one of the two locations mentioned above, or simultaneously in both locations; the embodiments of this application do not limit this.

[0023] Furthermore, after the water-retaining agent is applied to the paper surface, the coating typically contains a large amount of water or solvent. If the imaging layer is directly applied without drying the water-retaining agent coating, the residual water or solvent may cause incompatibility, delamination, or interface defects with the photocurable resin in the imaging layer, affecting the adhesion and film quality of the imaging layer. By setting an oven 6 between the first coating assembly 2a and the second coating assembly 2b, the paper enters the oven 6 for drying immediately after the water-retaining agent is applied. The heat in the oven 6 causes the water or solvent in the water-retaining agent coating to evaporate rapidly, and the water-retaining agent forms a dry and dense sealing film layer on the paper surface. This film layer can not only more effectively block the penetration of solvents in the subsequent imaging layer, but also provide a dry and flat substrate surface for the coating of the imaging layer, which is conducive to the uniform spreading and good adhesion of the imaging layer. Similarly, when the oven 6 is located between the second coating assembly 2b and the imprinting mechanism 3, the solvent in the imaging layer is dried and removed before imprinting, and the viscosity and solid content of the imaging layer are improved, so that the imaging layer has better deformation retention during the imprinting process, and the micro-nano structure on the imprinting roller 311 can be more accurately copied into the imaging layer.

[0024] In this embodiment, an oven 6 is installed between coating processes to allow for timely drying of the water-retaining agent coating and the imaging layer. Drying after water-retaining agent coating allows the water-retaining agent to form a stable dry film on the paper surface, eliminating the adverse effects of residual moisture or solvent in the water-retaining agent on the subsequent imaging layer coating quality and improving the interfacial adhesion and compatibility between the imaging layer and the water-retaining agent substrate. Drying after imaging layer coating allows the imaging layer to reach a suitable viscosity and rheological state for imprinting, which is beneficial for the accurate transfer and shape retention of micro-nano structures during imprinting, and helps improve the resolution and structural clarity of the imprinted image.

[0025] In one embodiment of this application, the oven 6 is provided with a first conveying structure 61 and a second conveying structure 62. The first conveying structure 61 includes a plurality of first conveying rollers 611 spaced apart along the length of the oven 6. The plurality of first conveying rollers 611 are disposed between the first coating component 2a and the second coating component 2b, so that the oven 6 can dry the paper coated with a water-retaining agent. The second conveying structure 62 includes a plurality of second conveying rollers 621 spaced apart along the length of the oven 6. The plurality of second conveying rollers 621 are disposed between the second coating component 2b and the printing mechanism 3, so that the oven 6 can dry the paper coated with an imaging layer. The first conveyor roller 611 uniformly conveys the paper coated with water-retaining agent. Combined with a low temperature and heat source suitable for the film-forming properties of the water-retaining agent, it can quickly dry the water-retaining agent, forming a dense isolation film, while avoiding high-temperature damage to the porous paper substrate. The stable conveying speed ensures that all parts of the paper are heated for the same duration, eliminating the problem of localized over- or under-drying. The second conveyor roller 621 correspondingly conveys the paper coated with the imaging layer. Matching the drying parameters of the imaging layer coating, it adjusts the appropriate conveying speed and drying temperature. During stable conveying, it precisely removes excess diluent solvent from the imaging layer while retaining suitable humidity for subsequent printing. Thus, by setting the first conveyor structure 61 and the second conveyor structure 62 respectively, the two drying structures operate independently without interference. The conveyor rollers, arranged orderly along the length of the oven 6, prevent the paper from directly contacting the heating components inside the oven 6, avoiding the risk of localized overheating and deformation. Combined with the overall linear conveying process of the equipment, it achieves targeted and efficient drying of the layered coating.

[0026] In one embodiment of this application, the first conveying structure 61 and the second conveying structure 62 are arranged vertically at intervals, and the projection of the first conveying structure 61 onto the bottom of the oven 6 is within the projection of the second conveying structure 62 onto the bottom of the oven 6. By stacking the two conveying structures vertically, the two sets of conveying structures, which would normally need to be arranged sequentially along the paper's travel direction, are compressed into the upper and lower spaces of the same oven 6. The length of the oven 6 in the paper's travel direction does not need to be significantly increased due to the two conveying structures, thus helping to reduce the length of the oven 6 and even the entire paper printing equipment 100. Furthermore, the projection of the first conveying structure 61 is within the projection of the second conveying structure 62, ensuring that the two conveying structures are highly overlapping in the horizontal plane, preventing either conveying structure from exceeding the range of the other in the horizontal direction and causing an additional increase in the width or length of the oven 6. Meanwhile, the stacked arrangement allows for a certain degree of heat sharing and exchange between the upper and lower conveyor structures inside the oven 6. Heat radiated from the upper conveyor structure can diffuse downwards to assist in heating, while residual heat from the lower conveyor structure can rise to the upper layer for preheating. The conveyor rollers in both layers guide the paper through their respective heating zones, ensuring full utilization of the heat energy within the oven 6. Furthermore, the second conveyor rollers 621 in the second conveyor structure 62 have a larger horizontal span, resulting in a longer travel path and longer dwell time for the paper. This adapts to the process requirements where the imaging layer coating requires a longer drying time due to its greater thickness or higher solvent content. In contrast, the first conveyor rollers 611 in the first conveyor structure 61 have a smaller horizontal span, resulting in a relatively shorter travel path for the paper. This adapts to the characteristics of a typically thinner water-retaining agent coating and relatively lower drying requirements.

[0027] In this embodiment, by stacking the first conveying structure 61 and the second conveying structure 62 vertically, the footprint of the oven 6 in the length direction can be reduced while ensuring that each conveying structure has sufficient conveying rollers and paper travel path. This shortens the overall length of the paper printing equipment 100, reducing the space requirements for the installation site and facilitating the complementary utilization of heat between the two layers inside the oven 6, thus reducing heat loss and energy consumption. Simultaneously, the projection of the first conveying structure 61 onto the bottom of the oven 6 falls within the projection of the second conveying structure 62 onto the bottom of the oven 6. This ensures that the conveying path lengths of the two conveying structures are reasonably matched to the drying requirements of their respective coatings. The water-retaining agent coating dries within a shorter path, while the imaging layer coating dries sufficiently within a longer path. This avoids performance degradation caused by over-baking of the water-retaining agent coating and ensures the drying quality of the imaging layer coating.

[0028] In one embodiment of this application, the paper imprinting apparatus 100 further includes a corona component 7 disposed on the frame 1. The corona component 7 is located between the oven 6 and the second coating component 2b, and is used to perform corona treatment on the dried paper.

[0029] Understandably, the corona component 7 is a surface treatment device. Its core components typically include a high-frequency high-voltage generator and a corona discharge electrode. The alternating high voltage generated by the high-frequency high-voltage generator is applied to the corona discharge electrode, causing the air between the electrode and the grounding roller to ionize and break down, forming a corona discharge region. When the paper passes through this corona discharge region, its surface is modified by bombardment of high-energy electrons and active particles. Furthermore, after the paper is coated with a water-retaining agent in the first coating component 2a and dried in the oven 6, the water-retaining agent forms a dry and dense sealing film layer on the paper surface. Although this film layer effectively seals the porous structure of the paper, the surface energy of the water-retaining agent film layer may be low. Especially when the water-retaining agent uses certain hydrophobic polymer materials, there may be a large difference between its surface tension and the subsequently coated photocurable imaging layer, resulting in poor wettability, uneven coating, or insufficient adhesion of the imaging layer on the water-retaining agent film layer. Therefore, in this embodiment, by setting a corona component 7 between the oven 6 and the second coating component 2b, the dried water-retaining agent film is subjected to corona treatment. The high-energy active particles generated by the corona discharge bombard the surface of the water-retaining agent film, causing the molecular chains on the film surface to break and introducing oxygen-containing polar groups, thereby increasing the surface energy and polarity of the water-retaining agent film and improving its wettability to the photocurable imaging layer.

[0030] In one embodiment of this application, the frame 1 includes a coating frame 11, and both the first coating assembly 2a and the second coating assembly 2b include coating assemblies. Each coating assembly includes a coating structure 21, which includes a coating roller 211 and a coating pressure roller 212 disposed on the coating frame 11. The coating pressure roller 212 is movably disposed relative to the coating frame 11 to press the paper against the coating roller 211, so that the coating roller 211 can coat the paper with a water-retaining agent or an imaging layer.

[0031] Understandably, the surface of the coating roller 211 may have a textured surface or be specially treated to improve its coating capacity. The coating carried on the coating roller 211 is transferred to the paper surface during the rotation of the coating roller 211. The coating pressure roller 212 is typically a rubber-coated roller or a polyurethane roller, whose surface has a certain elasticity, enabling it to uniformly press the paper against the surface of the coating roller 211 when pressed against it. The coating pressure roller 212 is movably positioned relative to the coating frame 11, allowing it to move closer to or further away from the coating roller 211, thereby adjusting the pressure or gap between the coating pressure roller 212 and the coating roller 211. Furthermore, during coating, the paper passes through the gap between the coating roller 211 and the coating pressure roller 212, and the coating pressure roller 212 presses the paper against the surface of the coating roller 211. The coating carried on the surface of the coating roller 211 is uniformly transferred to the paper surface under the pressure between the roller surface and the paper. Thus, the coating roller 212 is movably positioned relative to the coating frame 11, allowing the operator to adjust the relative position between the coating roller 212 and the coating roller 211 according to the thickness of different papers and the viscosity of different coatings. When processing thicker paper, the distance between them can be increased; when processing thinner paper, the distance can be decreased, ensuring that the paper is always appropriately pressed against the surface of the coating roller 211. This ensures uniform coating transfer and avoids problems such as paper deformation due to excessive pressure or uneven coating due to insufficient pressure. Furthermore, the first coating assembly 2a and the second coating assembly 2b adopt the same structure, which facilitates the standardization and universality of equipment components, and helps reduce the manufacturing and maintenance costs of the equipment.

[0032] In one embodiment of this application, the coating pressure roller 212 is movably arranged in the vertical direction so that the distance between the coating roller 211 and the coating pressure roller 212 is adjustable. Specifically, when a thicker paper needs to be coated, the distance between the coating pressure roller 212 and the coating roller 211 can be increased to provide sufficient passage space for the thicker paper; when a thinner paper needs to be coated, the distance between the coating pressure roller 212 and the coating roller 211 can be decreased so that the coating pressure roller 212 can apply appropriate pressure to the thinner paper. Thus, by arranging the coating roller 212 movably in the vertical direction, the distance between the coating roller 211 and the coating roller 212 is adjustable. This allows the paper coating mechanism 2 to adapt to paper of different thicknesses, thus expanding the applicability of the equipment. Furthermore, by adjusting the distance, the clamping force can be controlled, allowing for precise adjustment of the amount and uniformity of coating transfer to meet different coating requirements. This is beneficial for obtaining a coating with uniform thickness and stable quality, improving coating quality. It also facilitates paper feeding operations. During feeding, the distance can be increased to allow the paper to pass through smoothly, and after feeding, the distance can be adjusted to a suitable distance for coating, thereby improving operational convenience and production efficiency.

[0033] In one embodiment of this application, the coating structure 21 includes a coating seat 213, one end of which is rotatably mounted on the coating frame 11 about a horizontally extending axis. The coating assembly also includes a first linear drive structure 214, which is drivenly connected to the other end of the coating seat 213 to drive the coating seat 213 to swing. A coating pressure roller 212 is mounted on the coating seat 213. Thus, by swinging the coating seat 213, the position of the coating pressure roller 212 can be adjusted, ensuring smooth and reliable movement of the coating pressure roller 212. This avoids jamming and vibration problems that may occur in linear motion, thus contributing to the stability of the coating process. The first linear drive structure 214 is driven to the other end of the coating seat 213. Utilizing the lever principle, the first linear drive structure 214 can generate a large pressing force at the coating roller 212 with a small driving force. At the same time, the large stroke of the first linear drive structure 214 corresponds to the small displacement of the coating roller 212, which can finely adjust the position of the coating roller 212, which is beneficial for accurately controlling the coating thickness and coating uniformity.

[0034] In the paper printing equipment 100, the paper is typically conveyed by the take-up roller 5. After being released from the unwind roller 4, the paper passes through each coating assembly and the printing assembly 31 in sequence, and is finally wound up by the take-up roller 5. During the coating process, the paper is pressed against the surface of the coating roller 211 by the coating pressure roller 212. There is a large contact friction between the coating roller 211 and the paper. If the coating roller 211 does not have the ability to rotate actively, the conveying of the paper in the coating area depends entirely on the traction force of the take-up roller 5. The take-up roller 5 needs to provide a sufficiently large traction force to overcome the frictional resistance between the coating roller 211 and the paper in order to pull the paper out from between the coating roller 211 and the coating pressure roller 212. However, the tensile strength of the paper is limited, and excessive traction force can easily cause the paper to be stretched, deformed, or even torn. Therefore, in one embodiment of this application, the coating structure 21 also includes a coating motor 215 disposed on the coating frame 11. The coating motor 215 is drivenly connected to the coating roller 211 to drive the coating roller 211 to rotate. Thus, by setting up the coating motor 215, on the one hand, by adjusting the rotation speed of the coating motor 215, the linear speed of the coating roller 211 is matched with the paper conveying speed. This can actively drive the paper forward, so that the paper does not bear any additional traction tension in the coating area. This can effectively avoid the problem of paper stretching, deformation or tearing caused by excessive traction force. On the other hand, it can also avoid problems such as paper slippage, accumulation or stretching caused by the mismatch between the rotation speed of the coating roller 211 and the paper conveying speed. This is conducive to ensuring the smoothness of paper conveying and the stability of the coating process.

[0035] In one embodiment of this application, the coating assembly further includes a doctor blade structure 22 and a feed trough structure 23. The doctor blade structure 22 includes a coating doctor blade 221 connected to the coating frame 11 for scraping off the coating liquid on the coating roller 211. The feed trough structure 23 includes a coating trough 231 connected to the coating frame 11, with at least a portion of the coating roller 211 located within the coating trough 231, allowing the coating roller 211 to be immersed in the coating liquid. During rotation, the portion of the coating roller 211 immersed in the coating trough 231 picks up the coating material, and as the coating roller 211 continues to rotate, the picked-up coating material is carried out of the coating trough 231. The blade of the coating blade 221 contacts or maintains a small gap with the surface of the coating roller 211. When the surface of the coating roller 211, which has been dipped in coating material, passes the coating blade 221, the coating blade 221 scrapes off excess coating material from the surface of the coating roller 211, leaving only a coating layer of a predetermined thickness on the surface of the coating roller 211. The scraped-off excess coating material flows back into the coating tank 231 along the coating blade 221, realizing the recycling of coating material. After the coating blade 221 scrapes off the excess coating material, the surface of the coating roller 211 retains a uniform coating layer. This coating layer rotates with the coating roller 211 to the pressing area between the coating roller 211 and the coating pressure roller 212, and is transferred to the paper surface under the pressing action of the coating pressure roller 212, forming a uniform coating. In this way, by setting the material tank structure 23, the coating roller 211 can be immersed in the coating tank 231 to pick up coating material, realizing continuous automatic feeding without the need for manual addition of coating material, which helps to improve production efficiency. By incorporating a coating doctor blade 221 to scrape away excess coating from the surface of the coating roller 211, ensuring that only a predetermined thickness of coating layer remains on the surface of the coating roller 211, the amount of coating transferred can be effectively controlled, which is beneficial for obtaining a coating with uniform thickness and stable quality. At the same time, the scraped-off excess coating flows back into the coating tank 231 for recycling, which helps to reduce coating waste and lower production costs.

[0036] In one embodiment of this application, the coating blade 221 is movably configured relative to the coating holder 11, so that the distance between the coating blade 221 and the coating roller 211 is adjustable. Thus, by movably configuring the coating blade 221 relative to the coating holder 11, the adjustable distance between the coating blade 221 and the coating roller 211 allows for precise adjustment of the coating thickness according to different coating requirements. This enables the coating assembly to adapt to different coatings and coating thicknesses, thereby improving the versatility and flexibility of the equipment. Furthermore, it allows for precise control of coating metering and transfer, resulting in coatings with accurate thickness and good uniformity, meeting the stringent requirements for coating thickness accuracy in 3D nanoimaging, and improving the imaging quality of the imprinted image.

[0037] In one embodiment of this application, the doctor blade structure 22 further includes a first coating mounting roller 222, a first coating mounting seat 223, and a second coating mounting seat 224. The first coating mounting roller 222 is mounted on the coating frame 11, the first coating mounting seat 223 is mounted on the first coating mounting roller 222, and the second coating mounting seat 224 is movably mounted on the first coating mounting seat 223 in the vertical direction. The doctor blade 221 is movably mounted on the second coating mounting seat 224 in the horizontal direction. The first coating mounting roller 222, mounted on the coating frame 11, provides basic support for the entire doctor blade structure 22. The first coating mounting base 223 is mounted on the first coating mounting roller 222, and the second coating mounting base 224 is movably mounted on the first coating mounting base 223 in the vertical direction. By adjusting the vertical position of the second coating mounting base 224 relative to the first coating mounting base 223, the vertical position of the coating blade 221 can be adjusted, thereby changing the relative positional relationship between the coating blade 221 and the coating roller 211 in the vertical direction, and adjusting the contact position and contact angle between the blade edge of the coating blade 221 and the surface of the coating roller 211. The coating blade 221 is movably mounted on the second coating mounting base 224 in the horizontal direction. By adjusting the horizontal position of the coating blade 221 relative to the second coating mounting base 224, the horizontal position of the coating blade 221 can be adjusted, thereby changing the horizontal distance between the coating blade 221 and the coating roller 211, and precisely controlling the amount of coating removed by the coating blade 221 from the surface of the coating roller 211. Thus, by setting the first coating mounting roller 222, the first coating mounting seat 223, and the second coating mounting seat 224, the coating blade 221 can be adjusted in both the up-down and left-right directions, giving the coating blade 221 a multi-degree-of-freedom adjustment capability. This allows the contact position and contact angle between the coating blade 221 and the coating roller 211 to be changed, so that the cutting edge of the coating blade 221 can match the surface of the coating roller 211 at the optimal angle and position, improving the scraping effect and coating metering accuracy. It also allows for precise control of the distance between the coating blade 221 and the coating roller 211, thereby precisely controlling the thickness of the coating layer on the surface of the coating roller 211.

[0038] In one embodiment of this application, a first coating mounting roller 222 is rotatably mounted on a coating frame 11 about a front-to-back extending axis. The coating assembly also includes a doctor blade drive structure 225, which is drivenly connected to the first coating mounting roller 222 to drive the first coating mounting roller 222 to rotate. Thus, by controlling the angle at which the doctor blade drive structure 225 drives the first coating mounting roller 222 to rotate, the oscillation amplitude of the coating doctor blade 221 can be precisely controlled, achieving precise adjustment of the distance and angle between the coating doctor blade 221 and the coating roller 211. Further, the doctor blade drive structure 225 includes a first worm gear structure 2251 and a first operating wheel 2252. The worm gear of the first worm gear structure 2251 is disposed on the first coating mounting roller 222, the worm of the first worm gear structure 2251 is disposed on the coating frame 11, and the first operating wheel 2252 is disposed on the worm of the first worm gear structure 2251. Thus, by employing the first worm gear structure 2251, the large transmission ratio characteristic of the worm gear structure allows the operator to make minute adjustments to the position of the coating blade 221 by rotating the first operating wheel 2252. This high adjustment precision facilitates accurate control of the distance and angle between the coating blade 221 and the coating roller 211, thereby precisely controlling the coating thickness. Furthermore, the self-locking characteristic of the worm gear structure ensures that the coating blade 221 remains stably in the set position after adjustment, preventing displacement due to the impact of the coating material or equipment vibration during coating, thus ensuring the stability and consistency of the coating thickness. Simultaneously, the first operating wheel 2252 allows the operator to conveniently and intuitively adjust the position of the coating blade 221, simplifying the operation.

[0039] In one embodiment of this application, a first coating mount 223 is rotatably mounted on a first coating mount roller 222. The coating assembly further includes a second linear drive structure (not shown in the figure), which is disposed between the first coating mount roller 222 and the first coating mount 223 to drive the first coating mount 223 to rotate relative to the first coating mount roller 222. When the second linear drive structure extends or retracts, its driving force acts on the first coating mount 223, causing the first coating mount 223 to rotate relative to the first coating mount roller 222 about the axis of the first coating mount roller 222. The rotation of the first coating mount 223 drives the second coating mount 224 and the coating blade 221 mounted thereon to move together, thereby changing the position of the coating blade 221. This adjustment method is independent of the rotation drive of the first coating mounting roller 222 by the doctor blade drive structure 225. That is, the rotation of the first coating mounting base 223 relative to the first coating mounting roller 222 and the rotation of the first coating mounting roller 222 relative to the coating frame 11 are two independent movements, which can be superimposed or performed independently. Among them, the rotation of the first coating mounting roller 222 is mainly used to adjust the contact angle between the coating doctor blade 221 and the coating roller 211, while the rotation of the first coating mounting base 223 is mainly used to adjust the downward pressure of the coating doctor blade 221 in order to adjust the coating amount of the coating roller 211. Thus, by rotatably mounting the first coating mounting base 223 onto the first coating mounting roller 222 and setting the second linear drive structure to drive the first coating mounting base 223 to rotate relative to the first coating mounting roller 222, the coating blade 221 can be provided with additional adjustment freedom independent of the blade drive structure 225. This makes the position adjustment of the coating blade 221 more flexible and precise. The operator can make coarse adjustments to the coating blade 221 through the blade drive structure 225 and then make fine adjustments through the second linear drive structure to achieve precise setting of the position of the coating blade 221.

[0040] In one embodiment of this application, the coating trough 231 is movably disposed relative to the coating frame 11, so that the distance between the coating trough 231 and the coating roller 211 is adjustable. Thus, by movably disposing the coating trough 231 relative to the coating frame 11, the immersion depth of the coating roller 211 can be adjusted. Combined with the scraping action of the coating blade 221, the amount of coating material on the surface of the coating roller 211 can be more precisely controlled, which is beneficial for obtaining a coating with uniform thickness and stable quality. Further, the material trough structure 23 includes a second coating mounting roller 232, a first coating transmission structure 233, and a material trough drive structure 234. The second coating mounting roller 232 is mounted on the coating frame 11. The first coating transmission structure 233 includes a meshing gear and a rack. The rack is disposed in the coating trough 231, and the gear is disposed in the second coating mounting roller 232. The material trough drive structure 234 drives the second coating mounting roller 232 to rotate. Thus, by setting up a gear and rack transmission structure, the moving distance of the coating tank 231 can be precisely controlled, and the immersion depth of the coating roller 211 can be precisely adjusted. This is beneficial for accurately controlling the amount of material fed into the coating roller 211. Furthermore, once the coating tank 231 is adjusted to the correct position, it is less likely to be displaced by external forces, thus ensuring the stability of the immersion depth of the coating roller 211 during the coating process.

[0041] In one embodiment of this application, the material trough drive structure 234 includes a second worm gear structure 2341 and a second operating wheel 2342. The worm gear of the second worm gear structure 2341 is disposed on the second coating mounting roller 232, the worm of the second worm gear structure 2341 is disposed on the coating frame 11, and the second operating wheel 2342 is disposed on the worm of the second worm gear structure 2341. Thus, by employing the second worm gear structure 2341, the large transmission ratio characteristic of the worm gear structure can be utilized, allowing the operator to make minute adjustments to the position of the coating trough 231 by rotating the second operating wheel 2342. This high adjustment precision is beneficial for accurately controlling the immersion depth and material feeding amount of the coating roller 211. Furthermore, the self-locking characteristic of the worm gear structure ensures that the coating trough 231 remains stably in the set position after adjustment, preventing displacement due to changes in the weight of the coating material within the coating trough 231 or vibrations during equipment operation, thus ensuring the stability of the material feeding amount and the consistency of the coating thickness during the coating process. By setting a second operating wheel 2342, the operator can conveniently and intuitively adjust the position of the coating tank 231. When used in conjunction with the first operating wheel 2252, the operator can independently adjust the position of the coating blade 221 and the coating tank 231 to achieve precise control of the coating parameters.

[0042] In one embodiment of this application, the coating assembly further includes a guide structure 24, which includes a guide roller 241 disposed on the coating frame 11. The guide roller 241 is located on the front side of the coating structure 21 to guide the paper into the coating structure 21. Thus, by providing the guide roller 241 on the front side of the coating structure 21, the paper is guided and pre-treated before entering the coating structure 21. This ensures that the paper enters the coating structure 21 at the correct angle and direction, guaranteeing a suitable wrap angle and contact area between the paper and the coating roller 211, which is beneficial for uniform coating transfer and improves coating uniformity. Furthermore, it eliminates wrinkles and looseness in the paper, allowing the paper to enter the coating area in a flat state, avoiding coating defects caused by uneven paper and contributing to improved coating quality. Furthermore, the guide roller 241 is movably mounted on the coating frame 11. The guide structure 24 also includes a guide swing arm 242 and a third worm gear structure 243. One end of the guide swing arm 242 is rotatably mounted to the guide roller 241, and the other end is fixedly connected to the worm wheel of the third worm gear structure 243. The worm wheel of the third worm gear structure 243 is rotatably mounted on the coating frame 11, and the worm of the third worm gear structure 243 is mounted on the coating frame 11, so that the guide swing arm 242 can swing. By adjusting the position of the guide roller 241, the wrap angle between the paper and the coating roller 211 can be changed. The size of the wrap angle directly affects the transfer effect and coating uniformity of the coating. An appropriate wrap angle can ensure that the coating is fully and evenly transferred to the paper surface, improving the coating quality. It can also change the tension distribution of the paper in the coating area, so that the paper maintains appropriate tension during the coating process, avoiding excessive tension that causes paper stretching and deformation or insufficient tension that causes paper loosening and wrinkling. Furthermore, by setting a third worm gear structure 243, it is ensured that the guide roller 241 is in a stable position after adjustment and will not be displaced due to changes in paper tension or equipment vibration, thereby ensuring the stability of the coating process and the consistency of coating quality.

[0043] In one embodiment of this application, the frame 1 further includes an impression frame 12, and the impression assembly 31 includes an impression roller 311 and an impression pressure roller 312 disposed on the impression frame 12. The impression pressure roller 312 is movably disposed relative to the impression frame 12 to press the paper against the impression roller 311, so that the impression roller 311 can press the dried paper to imprint an image onto the paper's imaging layer. The photocuring assembly 32 is disposed on the impression roller 311 to irradiate the imprinted paper to cure the paper's imaging layer.

[0044] The impression frame 12 serves as the basic support frame for the impression mechanism 3, primarily providing a stable mounting base for the impression assembly 31 and the photopolymerization assembly 32. The impression assembly 31 includes an impression roller 311 and an impression pressure roller 312. The impression roller 311 is a cylindrical roller structure with a fine micro / nano structure template corresponding to the target image on its outer circumference, used to imprint fine structural images such as 3D nano-images and laser holographic images onto the imaging layer of the paper. The impression pressure roller 312 is also a cylindrical roller structure, located on one side of the impression roller 311, used to cooperate with the impression roller 311 to press the paper firmly. The impression pressure roller 312 is movably positioned relative to the impression frame 12, meaning it can move relative to the impression frame 12 in a specific direction, thereby adjusting the distance and clamping force between the impression pressure roller 312 and the impression roller 311. The photocuring component 32 typically uses an ultraviolet light source, such as an array of UV-LED beads or an ultraviolet lamp tube, and is mounted on the impression roller 311 to photocur the imaging layer immediately after the impression is completed.

[0045] Further, the coated and dried paper enters between the impression roller 311 and the impression pressure roller 312. The impression pressure roller 312 presses the paper tightly against the outer surface of the impression roller 311. Under pressure, the imaging layer on the paper surface adheres tightly to the micro-nano structure template on the outer surface of the impression roller 311, and the micro-nano pattern structure on the template is replicated and pressed into the imaging layer. The photocuring component 32 is disposed on the impression roller 311. When the paper is pressed tightly against the surface of the impression roller 311 and the imaging layer has been imprinted with a fine pattern by the template, the photocuring component 32 emits ultraviolet light or other photocuring light source from inside the impression roller 311. The light passes through the roller wall of the impression roller 311 and reaches the imaging layer, causing the photocuring components in the imaging layer to undergo a cross-linking polymerization reaction, permanently curing and fixing the micro-nano structure pattern that has been imprinted in the imaging layer.

[0046] In this embodiment, the movement of the impression roller 312 allows for flexible adjustment of the clamping force according to different paper thicknesses and impression process requirements, ensuring optimal adhesion between the paper and the impression roller 311 at all times. This guarantees the impression accuracy and consistency of fine images and facilitates paper feeding and replacement operations. Simultaneously, the photocuring component 32 is positioned on the impression roller 311, allowing the photocuring process to be completed synchronously while the paper is pressed against the surface of the impression roller 311. The imaging layer remains tightly adhered to the template surface at the moment of curing, preventing the micro / nano structure from deforming or collapsing due to elastic recovery after the paper leaves the impression roller 311.

[0047] In one embodiment of this application, the impression roller 311 includes a roller body 3111 and a transparent plate cylinder 3112 sleeved on the roller body 3111. The photocuring component 32 is disposed on the outer peripheral surface of the roller body 3111 and is located between the roller body 3111 and the transparent plate cylinder 3112. Thus, by setting the transparent plate cylinder 3112, it can serve as both an impression working surface that carries the micro-nano structure template and a light-transmitting window of the photocuring component 32. This allows the curing light emitted by the photocuring component 32 to penetrate the plate cylinder from the inside of the impression roller 311 and irradiate the imaging layer. The irradiation area of ​​the curing light highly overlaps with the impression contact area. The imaging layer can obtain uniform and sufficient light curing during the impression process, and the image structure is locked in the most accurate state, thereby greatly improving the micro-nano level precision and structural integrity of the impression image.

[0048] In one embodiment of this application, the impression assembly 31 further includes a peeling roller 315 movably mounted on the impression frame 12 in the vertical direction. The peeling roller 315 and the impression roller 312 are respectively disposed on both sides of the impression roller 311. The impression roller 312 is located on the paper entry side of the impression roller 311 and is used to press the paper against the surface of the impression roller 311. The peeling roller 315 is located on the paper exit side of the impression roller 311 and forms two constraint points with the impression roller 312 in the circumferential direction of the impression roller 311. Together, they define the covering area of ​​the paper on the outer circumferential surface of the impression roller 311. Furthermore, the paper enters the surface of the impression roller 311 from one side of the impression roller 312. Under the pressing action of the impression roller 312, it begins to adhere to the outer circumferential surface of the impression roller 311 and is conveyed forward along the circumference of the impression roller 311 as it rotates. The paper continues to adhere to the surface of the impression roller 311 until it moves to the other side where the peeling roller 315 is located. The peeling roller 315 guides the paper to detach from the surface of the impression roller 311. During this process, the impression roller 312 and the peeling roller 315 are respectively located on both sides of the impression roller 311. They serve as the starting point and ending point for the paper to adhere to the impression roller 311, respectively, and together define the coverage arc range of the paper on the outer circumferential surface of the impression roller 311. Within this coverage arc range, the paper remains tightly adhered to the surface of the transparent plate cylinder 3112 of the impression roller 311, and the imaging layer maintains sufficient and continuous contact with the micro-nano structure template on the plate cylinder. Meanwhile, the peeling roller 315 is movably arranged in the vertical direction. When the peeling roller 315 moves closer to the impression roller 311, the position where the paper leaves the impression roller 311 extends further along the circumference of the impression roller 311. The wrapping angle of the paper on the impression roller 311 increases, and the range of the wrapping arc expands accordingly, increasing the contact area between the paper and the impression roller 311. Conversely, when the peeling roller 315 moves away from the impression roller 311, the wrapping angle decreases, and the contact area is reduced accordingly, thereby achieving the adjustment of the paper wrapping range. Furthermore, after the paper is pressed by the impression roller 311 and cured by the photocuring component 32, the imaging layer has been cured and shaped, and a certain adhesion and mechanical interlocking force is generated between it and the micro-nano structure template on the surface of the transparent plate cylinder 3112. When the paper continues to rotate with the impression roller 311 to the side where the peeling roller 315 is located, the peeling roller 315 applies support and guidance to the paper, so that the paper is gradually peeled off from the surface of the transparent plate cylinder 3112 of the impression roller 311 at a controllable angle and with uniform force under the guidance of the peeling roller 315. The separation between the paper and the transparent plate cylinder 3112 proceeds smoothly along a continuous and stable peeling line, avoiding local tearing and image damage caused by sudden angle changes or uneven force when the paper leaves the impression roller 311.

[0049] In this embodiment, by providing a peeling roller 315 on the paper-leaving side of the impression roller 311, the paper gradually detaches from the surface of the transparent plate cylinder 3112 at a reasonable angle and with uniform tension after impressioning and photocuring. This avoids the peeling impact caused by the paper suddenly detaching from the impression roller 311 without guidance, and prevents defects such as cracking, peeling, or texture deformation of the cured fine image structure due to instantaneous concentrated stress during the peeling process. This helps protect the integrity of the micro-nano-level structure and surface smoothness of the imaging layer image. On the other hand, it can be separated from the impression roller 312 and positioned on both sides of the impression roller 311, allowing the paper to be separated from the impression roller 311 by the paper-leaving side. The two circumferential constraint points on roller 11 jointly define the paper's covering arc segment. By adjusting the vertical position of the peeling roller 315, the covering angle of the paper on the impression roller 311 is changed. This expands the contact area and contact time between the paper and the impression roller 311, allowing for more sufficient imprinting contact and a longer photocuring time between the imaging layer and the micro / nano structure template. This improves the integrity and curing depth of the imprinted image, ensuring the imprinting quality of fine structure images, especially high aspect ratio micro / nano structures. It also enhances the stability of the paper on the impression roller 311, reducing the risk of paper slippage and displacement during the imprinting process.

[0050] In one embodiment of this application, the impression roller 312 is movably mounted on the impression frame 12 in the vertical direction. The impression assembly 31 further includes a third linear drive structure 313 disposed on the impression frame 12. The third linear drive structure 313 is drivenly connected to the impression roller 312 to drive the impression roller 312 to move vertically. Thus, by driving the impression roller 312 to move vertically through the third linear drive structure 313, the impression roller 312 can quickly switch between a pressing position and a retracting position, which can both press the paper against the impression roller 311 so that the impression roller 311 can press the paper, and release the paper to facilitate paper feeding. It is understood that the third linear drive structure 313 can be of various types, such as a cylinder or a hydraulic cylinder, and the embodiments of this application do not limit it in this regard.

[0051] In the paper printing equipment 100, the paper is typically conveyed by the take-up roller 5. After being released from the unwind roller 4, the paper passes through each coating assembly and the printing assembly 31 in sequence, and is finally wound up by the take-up roller 5. During the printing process, the paper is pressed against the surface of the impression roller 311 by the impression roller 312. There is a large contact friction between the impression roller 311 and the paper. If the impression roller 311 does not have the ability to rotate actively, the conveying of the paper in the coating area depends entirely on the traction force of the take-up roller 5. The take-up roller 5 needs to provide a sufficiently large traction force to overcome the frictional resistance between the impression roller 311 and the paper in order to pull the paper out from between the impression roller 311 and the impression roller 312. However, the tensile strength of paper is limited, and excessive traction force can easily cause the paper to be stretched, deformed, or even torn. Therefore, in one embodiment of this application, the printing assembly 31 also includes an impression motor 314 disposed on the impression frame 12. The impression motor 314 is drivenly connected to the impression roller 311 to drive the impression roller 311 to rotate. Thus, by driving the impression roller 311 to rotate actively through the impression motor 314, the paper feeding in the impression area changes from a pulling type to an active feeding type. The tension distribution of the paper on both sides of the impression area is more balanced, which can significantly reduce the traction load of the take-up roller 5 and the longitudinal tensile stress on the paper. This can effectively protect the structural integrity of the paper and avoid image distortion and uneven impression depth caused by paper stretching and deformation. At the same time, it can precisely control the rotation speed of the impression roller 311, so that the rotational linear speed of the impression roller 311 is precisely synchronized with the overall paper feeding speed. This avoids relative sliding between the surface of the impression roller 311 and the paper due to speed difference, which helps to eliminate scratch damage and image ghosting on the surface of the imaging layer caused by sliding friction, thereby helping to improve the impression accuracy and surface quality.

[0052] In one embodiment of this application, the imprinting mechanism 3 further includes a tensioning component 33 disposed between the coating mechanism 2 and the imprinting assembly 31 to keep the paper taut. Thus, by providing the tensioning component 33, an appropriate tension force is applied to the passing paper, eliminating slack, sagging, and wrinkling caused by factors such as the paper's own weight, post-coating humidity changes, and speed differences between the rollers during transport. This ensures the paper enters the imprinting area between the imprinting roller 311 and the imprinting pressure roller 312 in a flat and taut state, guaranteeing uniform adhesion of the paper's imaging layer to the micro / nano structure template on the surface of the imprinting roller 311 across the entire width.

[0053] In one embodiment of this application, the tensioning assembly 33 includes a tension mounting roller 331, a tension adjusting roller 332, a tension connecting arm 333, and a tension driving structure 334. The tension mounting roller 331 is rotatably mounted on the printing frame 12 about a front-to-back axis, and its tension is adjusted and movable in the left-to-right direction to keep the paper taut. One end of the tension connecting arm 333 is fixedly connected to the tension mounting roller 331, and the other end is used for mounting the tension adjusting roller 332. The tension driving structure 334 is located on the printing frame 12 and is drivenly connected to the tension mounting roller 331 to drive the tension mounting roller 331 to rotate. Thus, by setting the tension mounting roller 331 as a pivot center and by setting the tension connecting arm 333 to convert the rotational motion of the tension mounting roller 331 into the linear displacement motion of the tension adjusting roller 332, fine adjustment of the tension force can be achieved to meet the differentiated tension requirements under different paper materials, different coating states, and different printing speeds. Meanwhile, by setting a tensioning drive structure 334, the tensioning installation roller 331 is driven to rotate, so as to adjust the position of the tensioning installation roller 331.

[0054] In one embodiment of this application, the tension drive structure 334 includes a tension drive arm 3341 and a fourth linear drive structure 3342. One end of the tension drive arm 3341 is fixedly connected to the tension mounting roller 331, and one end of the fourth linear drive structure 3342 is hinged to the other end of the tension drive arm 3341, and the other end is hinged to the imprinting frame 12, for driving the tension drive arm 3341 to swing. Thus, by setting the tension drive arm 3341, the linear motion of the fourth linear drive structure 3342 is accurately converted into the rotational motion of the tension mounting roller 331, forming a simple and reliable crank-connecting rod drive mechanism. Simultaneously, both ends of the fourth linear drive structure 3342 are hinged. During the swinging process of the tension drive arm 3341, the hinged connection can adaptively compensate for the angular changes between the components when the tension drive arm 3341 swings, eliminating the additional stress and jamming risk caused by motion interference in rigid connections, ensuring smooth and reliable drive transmission.

[0055] In one embodiment of this application, the printing mechanism 3 further includes an illumination component 34 disposed on the printing frame 12, with the illumination component 34 positioned above the printing component 31. Thus, by providing the illumination component 34 above the printing component 31, on the one hand, a dedicated auxiliary lighting environment is provided for the printing station, enhancing the visibility and monitorability of the printing process. This allows operators to observe and monitor each stage and detail of the printing process in real time, reducing the risk of operational errors and missed quality defects due to insufficient ambient light. This helps improve the quality control level of printed products and the controllability of the production process. On the other hand, it provides convenient conditions for operators to perform daily operations and maintenance tasks such as paper feeding, plate replacement, equipment cleaning, and troubleshooting, reducing operational difficulties and safety hazards caused by insufficient light, and helping to improve the convenience of equipment operation and workplace safety.

[0056] In one embodiment of this application, the frame 1 is further provided with a winding motor 51, which drives and connects to a winding roller 5 to drive the winding roller 5 to wind up the paper. Thus, by setting the winding motor 51 to drive the winding roller 5, a stable and controllable paper conveying power can be provided to the paper printing equipment 100. At the same time, the winding motor 51 can coordinate with the coating motor 215 and the printing motor 314 to form a complete multi-motor synchronous drive system, thereby helping to ensure speed matching and tension balance of the paper throughout the unwinding, coating, printing, and winding processes.

[0057] Please see Figure 11 The paper printing device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be high-speed random access memory (RAM) or stable non-volatile memory (NVM), such as a disk storage device. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0058] like Figure 1As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a control program for the paper printing equipment.

[0059] exist Figure 1 In the paper printing device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the paper printing device of the present invention can be set in the paper printing device. The paper printing device calls the control program of the paper printing device stored in the memory 1005 through the processor 1001 and executes the control method of the paper printing device provided in the embodiment of the present invention.

[0060] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the control module 7, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0061] Please see Figure 12 , Figure 12 This is a schematic diagram of the first process of a paper imprinting method provided by the present invention.

[0062] An imprinting method is used in a paper imprinting apparatus, the paper imprinting apparatus including a coating mechanism and an imprinting mechanism, the coating mechanism including a first coating component and a second coating component, the imprinting mechanism including an imprinting component and a photocuring component disposed on the imprinting component, the paper imprinting method including the following steps: The imprinting method includes: S10: Coating: The paper is first passed through the first coating component, whereby the first coating component coats the paper with a water-retaining agent, and then passed through the second coating component, whereby the second coating component coats the paper coated with the water-retaining agent with an imaging layer. S20: Imprinting: Paper coated with the imaging layer is passed through the imprinting assembly and the photocuring assembly, so that the imprinting assembly can imprint an image from the imaging layer of the paper, and the photocuring assembly can photocur the imprinted image to form a solid shape.

[0063] In this embodiment, a water-retaining agent is first coated onto the paper surface. This agent penetrates the pores and capillary channels of the paper surface, forming a continuous and dense closed layer. This blocks the absorption channels of solvents and active monomers in the subsequent imaging layer coating, allowing the imaging layer coating applied by the second coating component to maintain good flowability and leveling on the surface of the water-retaining agent layer. This results in a uniformly thick and smooth imaging film layer on the paper surface. When the paper passes through the imprinting component, the uniform and smooth imaging layer can fully adhere to the imprinting plate under pressure, accurately replicating the micro-nano structures on the plate. Subsequently, the photocuring component instantly cures the imaging layer, solidifying and shaping the fine image structure within it. Thus, by applying a water-retaining agent undercoat, the problem of paper absorption and penetration of the imaging layer coating is solved. Because the photocurable components in the imaging layer are no longer unevenly absorbed by the paper, the composition ratio of each area of ​​the imaging layer remains consistent, achieving comprehensive and uniform curing during the photocuring process and avoiding image structure defects caused by incomplete local curing.

[0064] In one embodiment of this application, the paper printing apparatus further includes an oven, the oven comprising a component disposed between the first coating component and the second coating component; The step of first passing the paper through the first coating assembly to coat the paper with a water-retaining agent further includes: S11: The paper passes through the first conveying structure of the oven, enabling the oven to bake the paper coated with a water-retaining agent.

[0065] In this embodiment, after the first coating assembly coats the paper with a water-retaining agent, the water-retaining agent coating typically contains a large amount of water or solvent. At this time, the water-retaining agent is still in a wet and flowing state, and its function of sealing the paper pores has not been fully realized. If the imaging layer is directly coated on the undried water-retaining agent layer, the wet water-retaining agent may miscibly mix with the imaging layer coating or cause interface disturbance, resulting in a blurred interface between the two coating layers. The isolation and sealing effect of the water-retaining agent is weakened, and the film uniformity and optical performance of the imaging layer will also be affected. Therefore, by setting an oven between the first coating assembly and the second coating assembly, the paper coated with water-retaining agent is fully baked and dried before entering the second coating assembly. The heat provided by the oven can accelerate the evaporation of water or solvent in the water-retaining agent coating, allowing the water-retaining agent to quickly form a dry, dense, and continuous cured film layer on the paper surface. This cured film layer firmly seals the pores and capillary channels on the paper surface, forming a smooth and flat hard substrate. When the surface of the dried and cured water-retaining agent layer is then coated with the imaging layer coating by the second coating component, the imaging layer coating spreads and levels on the smooth and dense cured water-retaining agent layer. The interface between the two coating layers is clear and distinct, and no mixing or penetration occurs.

[0066] In one embodiment of this application, the paper imprinting apparatus further includes a corona component; After the paper passes through the oven, allowing the oven to bake the paper coated with a water-retaining agent, the process further includes: S12: The paper passes through the corona component, enabling the corona component to perform corona treatment on the baked paper.

[0067] In this embodiment, although the water-retaining agent layer after baking and drying in the oven has formed a dense closed film on the paper surface, the surface energy of this film may be relatively low. Especially when the water-retaining agent is a water-based polymer coating, the dried coating surface often exhibits certain hydrophobic or low surface energy characteristics. This leads to poor wetting of the subsequent imaging layer coating on the surface of the water-retaining agent layer, making it difficult for the coating to spread fully on the low-energy surface, easily resulting in problems such as pinholes, fisheyes, or uneven coating, affecting the film quality of the imaging layer. Therefore, by adding a corona discharge component after the oven to perform corona treatment on the surface of the dried water-retaining agent layer, the high-energy discharge introduces a large number of polar oxygen-containing functional groups on the surface of the water-retaining agent coating, increasing the surface energy and surface polarity of the coating, enhancing the wetting affinity of the water-retaining agent layer surface for the imaging layer coating, and enabling the imaging layer coating to spread rapidly on the surface of the corona-treated water-retaining agent layer and form a uniform and continuous film. Meanwhile, the micro-roughening effect produced by corona treatment on the surface of the water-retaining agent layer can increase the contact area between the water-retaining agent layer and the imaging layer, forming more mechanical anchoring points, which is conducive to enhancing the interlayer adhesion between the two coating layers, making the imaging layer more firmly bonded to the water-retaining agent layer.

[0068] In one embodiment of this application, the paper imprinting apparatus further includes an oven, which is disposed between the second coating assembly and the imprinting assembly; Before the paper coated with the imaging layer passes through the imprinting assembly and the photocuring assembly, the process further includes: S30: The paper passes through the second conveying structure of the oven, enabling the oven to bake the paper coated with the imaging layer.

[0069] In this embodiment, after the imaging layer is coated by the second coating assembly, the imaging layer coating usually contains a certain proportion of solvent or reactive diluent monomer. The freshly coated imaging layer is in a wet and flowing state, with low viscosity and weak cohesion. If this wet imaging layer is directly fed into the imprinting assembly for imprinting, on the one hand, the excessively low viscosity will cause the imaging layer to flow excessively and shift laterally under the imprinting pressure, resulting in blurred edges and coarsened lines in the imprinted image, making it difficult to guarantee the dimensional accuracy of the micro-nano structure; on the other hand, a large amount of solvent remaining in the wet imaging layer may be trapped between the imaging layer and the imprinting plate during the imprinting process. During the subsequent photocuring and removal processes, the solvent evaporates to form bubbles or micropores, damaging the structural integrity of the imprinted image. Therefore, by setting up an oven between the second coating assembly and the imprinting assembly, the imaging layer is moderately baked to evaporate and remove excess solvent in the imaging layer, thereby increasing the solid content, viscosity, and cohesion of the imaging layer. The coating changes from a free-flowing state to a semi-dry state with appropriate rheological properties. This not only retains sufficient deformability to accurately replicate the micro-nano structure of the imprinting plate under imprinting pressure, but also has sufficient cohesive strength to maintain the shape stability of the imprinted structure and prevent the pattern from springing back or collapsing after depressurization.

[0070] In one embodiment of this application, the coating amount of the imaging layer is 3-10 g / m². When the coating amount is less than 3 g / m², the film formed by the imaging layer on the paper surface is too thin. On the one hand, the thin film layer cannot completely cover any minor unevenness that may exist on the surface of the water-retaining agent layer, and the surface smoothness of the imaging layer is constrained by the substrate condition. On the other hand, an excessively thin imaging layer cannot provide enough material to fill the recessed areas of the micro-nano structure on the printing plate, and the deep details of the pattern cannot be completely replicated during printing, resulting in shallow image engraving, insufficient structural depth, and weakened optical diffraction effects. Conversely, when the coating amount exceeds 10 g / m², the excessive thickness of the imaging layer will bring several negative effects, including difficulty in solvent evaporation leading to a significant extension of drying time, increased internal stress in the thick coating causing cracking or curling, difficulty for ultraviolet light to penetrate to the bottom of the coating during photocuring leading to incomplete bottom curing, and increased production costs due to increased coating usage. Therefore, the coating amount is controlled within the range of 3-10 g / m², so that the imaging layer can form a film layer of moderate thickness and continuous integrity, and can be fully cured under reasonable drying time and photocuring conditions, providing sufficient material reserves for the accurate replication of micro and nano structures during the imprinting process.

[0071] In one embodiment of this application, the imaging layer is made of at least one of varnish, ink, or clear varnish. Varnish, ink, and clear varnish all possess excellent photocuring properties and film-forming performance, enabling them to rapidly undergo cross-linking polymerization under ultraviolet light, transforming from a liquid coating into a hardened film layer, permanently shaping the micro-nano structures etched onto the coating. Furthermore, varnish, with its high transparency and excellent gloss, is an ideal imaging material for holographic image imprinting. The diffraction effect of a holographic image depends on the diffraction and interference of light by the micro-nano structures on the imaging layer surface. A transparent varnish film layer does not absorb or scatter light, maximizing the preservation and display of the optical effects of the holographic image. Ink forms a brightly colored and firmly adhered color imaging layer on the smooth substrate provided by the water-retaining agent layer. The micro-nano structures imprinted on the ink layer, combined with the color effect of the pigments, can achieve a composite visual effect of color and three-dimensional image, expanding the expressive forms and application areas of imprinted products. The hard film layer formed after the varnish cures has excellent wear resistance and chemical resistance, effectively protecting the micro-nano structure of the imprinted image from damage during subsequent processing and use, thus extending the product's lifespan. Setting three materials as selectable imaging layer materials allows the paper imprinting equipment to flexibly select and switch imaging layer materials according to different product needs, thereby facilitating multi-functionality.

[0072] In one embodiment of this application, the water-retaining agent includes a water-based acrylic smoothing water-retaining coating, a water-based polyurethane smoothing water-retaining coating, or a water-based polyvinyl alcohol-based smoothing water-retaining coating. The water-based acrylic smoothing water-retaining coating is a water-based coating with an acrylic ester copolymer emulsion as the main film-forming substance. Acrylic ester copolymers have good film-forming properties, water resistance, and optical transparency. After drying, the coating formed on the paper surface is smooth and flat, with moderate hardness and good adhesion. The water-based polyurethane smoothing water-retaining coating is a coating with a water-based polyurethane dispersion as the main film-forming substance. Polyurethane coatings are known for their excellent flexibility, abrasion resistance, and high elasticity. After drying, the film formed is both flexible and dense, able to adapt to the bending and folding of paper during subsequent processing without easily cracking. The water-based polyvinyl alcohol-based smoothing water-retaining coating is a coating with polyvinyl alcohol or its modified forms as the main film-forming substance. Polyvinyl alcohol has excellent film-forming properties and aqueous solution coating properties. After drying, the coating has high transparency and good barrier properties, and the raw materials are widely available and low in cost.

[0073] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method of embossing for a paper embossing apparatus, characterized by, The paper imprinting equipment includes a coating mechanism and an imprinting mechanism. The coating mechanism includes a first coating component and a second coating component. The imprinting mechanism includes an imprinting component and a photocuring component disposed on the imprinting component. The imprinting method includes: Coating: The paper is first passed through the first coating component, where the first coating component coats the paper with a water-retaining agent, and then passed through the second coating component, where the second coating component coats the paper coated with the water-retaining agent with an imaging layer. Imprinting: Paper coated with the imaging layer is passed through the imprinting assembly and the photocuring assembly, so that the imprinting assembly can imprint an image from the imaging layer of the paper, and the photocuring assembly can photocur the imprinted image to form a solid shape.

2. The embossing method according to claim 1, characterized in that The paper printing equipment further includes an oven, which is disposed between the first coating assembly and the second coating assembly; The step of first passing the paper through the first coating assembly to coat the paper with a water-retaining agent further includes: The paper passes through the first conveying structure of the oven, enabling the oven to bake the paper coated with a water-retaining agent.

3. The embossing method according to claim 2, characterized in that The paper imprinting equipment also includes a corona component; After the paper passes through the oven, allowing the oven to bake the paper coated with a water-retaining agent, the process further includes: The paper passes through the corona electrode assembly, which enables the corona electrode assembly to perform corona treatment on the baked paper.

4. The embossing method according to claim 1, characterized in that The paper imprinting equipment also includes an oven, which is disposed between the second coating assembly and the imprinting assembly; Before the paper coated with the imaging layer passes through the imprinting assembly and the photocuring assembly, the process further includes: The paper passes through the second conveying structure of the oven, enabling the oven to bake the paper coated with the imaging layer.

5. The embossing method according to claim 1, characterized in that The coating amount of the imaging layer is 3-10 g / m2.

6. The embossing method according to claim 1, characterized in that The material of the imaging layer includes at least one of varnish, ink, or clear varnish.

7. The embossing method according to claim 1, characterized in that The water-retaining agent includes water-based acrylic smooth water-retaining coating, water-based polyurethane smooth water-retaining coating, or water-based polyvinyl alcohol smooth water-retaining coating.

8. A control device characterized by comprising: The control device includes a memory and a processor, and a control program for the paper printing apparatus stored in the memory and executable on the processor. The control device for the paper printing apparatus is configured to implement the steps of the printing method of the paper printing apparatus as described in claim 1.

9. A paper stamping apparatus characterized by comprising: include: The frame is equipped with an unwinding roller and a rewinding roller. The unwinding roller is used to feed the paper, and the rewinding roller is used to rewind the printed paper. The coating mechanism includes a first coating assembly and a second coating assembly disposed on the frame. The first coating assembly is used to coat the paper released from the unwinding roll with a water-retaining agent, and the second coating assembly is used to coat the paper coated with the water-retaining agent with an imaging layer; and... An imprinting mechanism includes an imprinting assembly and a photocuring assembly disposed on the frame. The imprinting assembly is used to imprint paper coated with an imaging layer to form an image on the imaging layer of the paper. The photocuring assembly is used to irradiate the imprinted paper to cure the imaging layer of the paper. A control device, comprising the control device according to claim 8, which is electrically connected with the coating mechanism and the stamping mechanism to control the operation of the coating mechanism and the stamping mechanism.

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