A low-damage scratch-preventing metal particle-preventing roll-to-roll electroplating cathode conductive roller shaft, a manufacturing method thereof, an electroplating method, and an electroplating apparatus

Abstract

The application discloses a low-damage scratch-proof and metal-particle-proof roll-to-roll electroplating cathode conductive roller shaft, a manufacturing method thereof, an electroplating method and an electroplating equipment, and belongs to the technical field of electroplating manufacturing. The conductive roller shaft comprises a rigid shaft body, an end conductive area, a middle functional support area and an electrical access part; the end conductive area is arranged at least one end of the rigid shaft body and is composed of a conductive metal material; the middle functional support area is arranged at the middle part of the rigid shaft body and is composed of an acid and alkali resistant flexible polymer material as a whole; and the end conductive area and the middle functional support area are arranged adjacently along the axial direction. During electroplating operation, the edge reserved area of the material to be processed is in contact with the end conductive area for conduction, and the effective electroplating area is in contact with the middle functional support area for support; the middle functional support area does not produce cathode polarization and has no metal deposition on the surface. The application is applicable to electroplating processing of flexible composite film substrates with a thickness in the range of 3-1000 microns, and the comprehensive yield of products can reach more than 98%, thus having good industrial practical value.

Description

Technical Field

[0001] This invention belongs to the field of electroplating manufacturing technology, specifically a roll-to-roll electroplating cathode conductive roller shaft with low damage, scratch resistance, and metal particle resistance, its manufacturing method, electroplating method, and electroplating equipment. Background Technology

[0002] In roll-to-roll continuous fluid electroplating, flexible composite films (such as substrates like PET, PP, PI, COP, or PS, typically with a thickness ranging from 3 to 1000 micrometers) are usually used as the substrate, and a negative potential is introduced through a cathode conductive roller. Metal ions in the electroplating solution gain electrons on the surface of the substrate, are reduced, and deposit to form a coating.

[0003] Currently, most cathode conductive rollers adopt an integral metal conductive pillar structure. In this structure, during electroplating, the entire roller surface is in a cathodic polarized state and directly contacts the electroplating solution. While metal ions are deposited on the film surface, they also undergo reduction deposition on the roller surface. With increasing operating time, a metal deposition layer and protrusions gradually form on the roller surface, accompanied by the formation of detached metal particles. The main problems arising from this are as follows: Product surface scratches: During the film's journey, it comes into full contact with the roller surface. The metal deposits on the roller surface and the difference in movement between the two can easily cause scratches on the film surface. For example... Figure 1 As shown, it demonstrates the dense scratches on the entire surface of the coating and substrate caused by hard contact and friction on a traditional integral metal cylindrical conductive roller.

[0004] Roller diameter variation affects film transport: After metal deposition on the roller surface, the actual outer diameter deviates from the design value, causing a mismatch between the roller surface linear velocity and the film transport speed, further aggravating film surface scratches and tension fluctuations. For example... Figure 2 As shown, after the metal deposition on the roller surface is thickened, the actual outer diameter deviates from the design value, and the roller axis speed becomes inaccurate, which further aggravates film surface scratches and tension imbalance.

[0005] Substrate punctures and particle coating: Under tension, the metal crystal protrusions on the roller surface may puncture or even penetrate extremely thin film substrates; simultaneously, metal particles detached from the roller surface adhere to the film surface and are subsequently coated by the coating layer, forming protruding metal particle defects. For example... Figure 3 and Figure 4 As shown, it clearly demonstrates the severe crystallization protrusions formed after the crystallized particles detach and are subsequently coated by the coating, as well as the microscopic cross-sectional damage caused by the substrate being punctured and perforated.

[0006] To address the aforementioned problems of metal deposition on roller surfaces and the resulting film damage, several improvements have been proposed in the field. For example, Chinese Patent CN116988130A discloses a horizontal roller electroplating apparatus. This apparatus features a conductive clutch with an anode conductive area and a cathode conductive area at the end of the roller, allowing the roller to be connected to the cathode for electroplating or switched to anode conduction to remove metal ions deposited on the surface. Chinese Patent CN118979296A discloses a roller pulse electroplating device that dissolves the metal deposited on the roller surface by applying pulse currents in both forward and reverse directions to the conductive roller, during the reverse pulse.

[0007] The aforementioned solutions primarily mitigate metal deposition issues on the roller surface by dissolving or removing existing deposited metal online. These methods require corresponding electrical controls or pulse power supplies, resulting in a relatively complex system structure. Furthermore, the reverse current generated during the decoction process may interfere with the product coating, and localized dynamic control failures can easily lead to fluctuations in product yield. In addition, these solutions do not alter the hard contact state between the roller surface and the effective area of ​​the film, and therefore cannot structurally prevent the risk of scratches and punctures to the film from roller surface particles.

[0008] Therefore, how to optimize existing technologies and reduce metal deposition on the roller surface and its damage to the film remains a technical problem that needs to be solved in this field. Summary of the Invention

[0009] The purpose of this invention is to provide a roll-to-roll electroplating cathode conductive roller shaft with low damage, scratch resistance, and metal particle resistance, as well as its manufacturing method, electroplating method, and electroplating equipment. Through a partitioned conductive structure design, the cathode potential is conducted only by the metal areas at both ends of the roller shaft, while a flexible insulating support structure in the middle isolates the polarization reaction, thereby preventing the generation of metal particles from the source, reducing the probability of film scratches, and improving the corrosion resistance and service life of the roller shaft.

[0010] The objective of this invention is achieved through the following technical solution: Technical Solution 1: A roll-to-roll electroplating cathode conductive roller shaft, comprising: Rigid shaft; An end conductive region is disposed at at least one end of the rigid shaft, and the end conductive region is made of a conductive metal material; The central functional support area is located in the middle of the rigid shaft and is used to support the effective electroplating area of ​​the material to be processed. The central functional support area is made of acid and alkali resistant flexible polymer material. After curing, the Shore A hardness of the flexible polymer material is 40° to 90°. An electrical connection section is electrically connected to the end conductive area and is used to connect to an external cathode power supply. The end conductive area and the middle functional support area are arranged adjacent to each other along the axial direction, and their outer surfaces are flush or nearly flush. After polishing or grinding, they together form a continuous cylindrical support working surface.

[0011] Preferably, the end conductive area and the middle functional support area are the outer surface areas of different axial sections of the rigid shaft itself.

[0012] Preferably, the end conductive area and the middle functional support area are functional sleeves fitted onto the outside of the rigid shaft or functional layers covering the outside of the rigid shaft.

[0013] Preferably, the rigid shaft is an integral hollow metal tube, the end conductive area is the uncut outer surface of the original metal tube at both ends of the integral hollow metal tube, the middle outer surface of the integral hollow metal tube is provided with an annular groove, and the middle functional support area is an insulating acid and alkali resistant flexible polymer coating layer filled, covered or solidified in the annular groove.

[0014] Preferably, the cutting depth of the annular groove is less than half the wall thickness of the integral hollow metal tube.

[0015] Preferably, the rigid shaft is a solid metal shaft, the end conductive area is the unmachined outer surface of the metal at both ends of the solid metal shaft, the middle outer surface of the solid metal shaft is provided with a diameter reduction groove, and the middle functional support area is an acid and alkali resistant flexible polymer coating area that is injection molded, molded or coated and cured in the diameter reduction groove.

[0016] Preferably, the rigid shaft is a central spindle, the end conductive area is formed by a metal conductive sleeve fitted on the end of the central spindle, and the middle functional support area is formed by an insulating sleeve fitted on the middle of the central spindle.

[0017] Preferably, the insulating sleeve is composed of two or more sub-sleeves spliced ​​together in the axial direction.

[0018] Preferably, the metal conductive sleeve and the central spindle are interference-fitted, and the outer support working surfaces of the metal conductive sleeve and the insulating sleeve are not provided with exposed screws, locating pins or fastening protrusions.

[0019] Preferably, one or both ends of the central spindle are provided with a detachable locking structure for axially locking the metal conductive sleeve and the insulating sleeve.

[0020] Preferably, there are two end conductive areas, which are respectively disposed on both sides of the central functional support area.

[0021] Preferably, there is one end conductive area, and the middle functional support area extends axially to the end where no end conductive area is provided.

[0022] Preferably, the acid and alkali resistant flexible polymer material is one or more of EPDM, PU, ​​NBR, PTFE or PVC.

[0023] Preferably, conductive particles may be incorporated into the acid and alkali resistant flexible polymer material to form a flexible conductive polymer layer; the conductive particles are one or more of conductive carbon black, graphite, carbon nanotubes, or metal powder.

[0024] Preferably, the shear bond strength between the central functional support area and the metal substrate is not less than 5 MPa.

[0025] Preferably, the end conductive area is made of one or more materials selected from stainless steel, copper, copper alloy, titanium, titanium alloy, nickel, nickel alloy, and chromium-containing or chromium-plated metals.

[0026] Preferably, an end bushing made of PP, PVC or other acid and alkali resistant insulating material is provided on the axial outer side of the end conductive area.

[0027] Preferably, the electrical connection part is a copper screw mechanism, which is disposed on the axial end face of the rigid shaft and is used for dynamic electrical connection with the mercury conductive slip ring assembly.

[0028] Preferably, the rigid shaft is further provided with a transmission gear shaft position that cooperates with an external transmission mechanism, wherein the transmission gear shaft position and the electrical connection part are located at the same end or at two separate ends.

[0029] Preferably, the surface roughness Ra of the end conductive region is ≤20μm, and the surface roughness Ra of the middle functional support region is ≤40μm.

[0030] Preferably, the overall coaxiality of the rigid shaft, the end conductive area, and the middle functional support area is ≤0.02mm, and the cylindricity is ≤0.015mm.

[0031] Preferably, the rigid shaft is made of one or more materials selected from stainless steel, copper, copper alloy, titanium, titanium alloy, nickel, nickel alloy, and chromium-containing or chromium-plated metals.

[0032] Preferably, the transmission gear shaft is one of a sector gear, helical gear, spur gear, helical gear, or worm gear, used for meshing with an external transmission mechanism.

[0033] Technical Solution Two: A method for manufacturing a roll-to-roll electroplated cathode conductive roller includes the following steps: S1: Form an end conductive region, wherein the end conductive region is disposed at at least one end of the rigid shaft and is made of a conductive metal material; S2: Form a central functional support area, so that the central functional support area is set in the middle of the rigid shaft to support the effective electroplating area of ​​the material to be processed. The central functional support area (3) is made of acid and alkali resistant flexible polymer material. The Shore A hardness of the flexible polymer material after curing is 40°~90°, and the central functional support area and the end conductive area are arranged adjacent to each other along the axial direction. S3: Polish, grind or precision assemble the outer surfaces of the end conductive area and / or the middle functional support area so that the outer surfaces of the two together form a continuous cylindrical support working surface.

[0034] Preferably, step S1 specifically includes: selecting a metal hollow tube, designing the tube length and end conductive width according to the product effective area width and the edge reserved area width, and forming the end conductive area on the uncut outer surface of the original metal tube at both ends; Step S2 specifically includes: CNC machining the middle part of the metal hollow tube to form an annular groove, and using EPDM, PU or NBR to coat and cure the annular groove to form the central functional support area; Step S3 is followed by: embedding a solid metal rod into the end of the hollow metal tube and machining the transmission gear shaft and electrical connection part.

[0035] Preferably, step S1 specifically includes: selecting a solid metal shaft, wherein the unmachined outer metal surfaces at both ends of the solid metal shaft form the end conductive area; Step S2 specifically includes: CNC cutting the middle part of the solid metal shaft to form a diameter reduction groove, and using injection molding, compression molding or overmolding curing process to form an acid and alkali resistant flexible polymer overmolding area in the diameter reduction groove, which serves as the middle functional support area.

[0036] Preferably, step S1 specifically includes: providing a central spindle and a metal conductive sleeve, and fitting the metal conductive sleeve onto the end of the central spindle to form the end conductive area; Step S2 specifically includes: fitting an insulating sleeve into the middle of the central main shaft, wherein the insulating sleeve is a single sleeve or formed by splicing together multiple sub-sleeves to form the central functional support area; Step S3 is followed by: axially locking the metal conductive sleeve and the insulating sleeve using an end locking structure.

[0037] Preferably, in step S1, an end conductive region is formed only at one end of the rigid shaft; in step S2, the central functional support region is extended to cover the other end.

[0038] Technical Solution 3: A roll-to-roll electroplating method includes the following steps: S1: Determine the axial width of the end conductive area and the axial width of the middle functional support area based on the effective electroplating area width of the material to be processed and the subsequent cutting edge width; S2: Guide the material to be processed through the cathode conductive roller, control the width or conveyor position of the material to be processed, so that the edge reserved area of ​​the material to be processed contacts the end conductive area, and the effective electroplating area of ​​the material to be processed contacts or is set opposite to the middle functional support area. S3: A cathode potential is applied to the end conductive area through the electrical connection part, and metal ions in the electroplating solution are reduced and deposited on the surface of the material to be treated to form a coating; S4: After electroplating is completed, the edge reserved area that is in contact with the end conductive area is cut or removed, and the effective electroplating area is retained.

[0039] Technical Solution 4: A roll-to-roll fluid electroplating device, comprising: Electroplating tank; An anode assembly is disposed within the electroplating tank; A DC rectifier has an anode output terminal and a cathode output terminal, wherein the anode output terminal is electrically connected to the anode assembly; Conductive slip ring assembly; And the roll-to-roll electroplating cathode conductive roller shaft, wherein the cathode conductive roller shaft is disposed above the electroplating tank, or the cathode conductive roller shaft is partially disposed inside the electroplating tank; One end of the conductive slip ring assembly is dynamically electrically connected to the electrical connection part of the cathode conductive roller shaft, and the other end is electrically connected to the cathode output terminal of the DC rectifier.

[0040] Preferably, the conductive slip ring assembly is a mercury conductive slip ring assembly, which is electrically connected to the electrical connection part of the cathode conductive roller shaft through a copper screw mechanism.

[0041] Compared with the prior art, the beneficial effects of the present invention are: 1. The roll-to-roll electroplating cathode conductive roller shaft provided by this invention has end conductive areas located at both ends of a rigid shaft and a central functional support area located in the middle of the rigid shaft, forming an axial partition structure suitable for horizontal or vertical electroplating equipment. During electroplating, the end conductive areas contact the edge reserved area of ​​the material to be processed and conduct cathode potential, while the central functional support area supports the effective electroplating area. The central functional support area is made of acid and alkali resistant flexible polymer material, which does not generate cathode polarization during electroplating, and metal ions in the electroplating solution will not be reduced and deposited on its surface, reducing metal particle shedding and film scratches caused by metal deposition on the roller surface. The outer surface of the central functional support area is flush with the outer surface of the end conductive areas, and after polishing or grinding, they together form a continuous cylindrical support working surface, preventing scratches caused by material interface differences during film transport. The central functional support area uses flexible material, and the contact with the film is flexible, which reduces the risk of scratches and punctures compared to the hard contact of a hard metal roller surface. Contact marks or small amounts of metal deposition near the conductive area at the end can be removed in subsequent slitting processes by removing the edge pre-reserved area, preserving the intact and effective electroplating area. This invention is applicable to the electroplating of flexible composite film substrates such as PET, PP, PI, COP, and PS with thicknesses ranging from 3 to 1000 micrometers. Using the conductive roller of this invention for electroplating production, the overall product yield can reach over 98%.

[0042] 2. The manufacturing method provided by this invention involves forming an annular groove or a diameter-reducing groove in the middle of a rigid shaft, filling or covering it with an acid- and alkali-resistant flexible polymer material to form a central functional support area, and then polishing or grinding the overall outer surface to make the outer surface of the central functional support area flush with the outer surface of the end conductive area. This method can be completed using conventional CNC machining equipment, molding and vulcanizing equipment, and precision grinding machines. The process is mature and suitable for mass production.

[0043] 3. The electroplating method provided by this invention is applicable to horizontal or vertical electroplating equipment. First, the axial widths of the end conductive area and the central functional support area are determined based on the effective electroplating area width of the product and the subsequent slitting edge width. Then, the material to be processed is guided through the cathode conductive roller, so that the edge reserved area of ​​the material contacts the end conductive area for conductivity, and the effective electroplating area contacts and supports the central functional support area. During the electroplating process, no cathode polarization occurs in the central functional support area, and no metal deposition occurs on its surface. After electroplating is completed, the edge reserved area is slitted and removed. Even if there are contact marks or a small amount of metal deposition in the edge reserved area, it does not affect the quality of the effective electroplating area of ​​the final product.

[0044] 4. The roll-to-roll fluid electroplating equipment provided by this invention employs axially partitioned cathode conductive rollers, suitable for horizontal or vertical electroplating processes, and can be arranged according to production needs. The central functional support area is made of acid and alkali resistant flexible polymer material, which does not generate cathode polarization during electroplating, reducing metal deposition on the roller surface and the resulting film scratches and particle coating. The equipment does not require an online plating removal circuit or pulse power supply, has a simple structure, and low maintenance costs. The cathode conductive rollers are positioned above or partially within the electroplating tank. The conductive slip ring assembly dynamically transmits the cathode potential of the DC rectifier to the rotating cathode conductive rollers, ensuring stable current transmission. Attached Figure Description

[0045] Figure 1 is a microscopic schematic diagram of the dense scratches on the substrate caused by the existing all-metal conductive roller. Figure 2 is a microscopic schematic diagram of the coating caused by existing roller metal deposition, resulting in scratches on the film surface and tension imbalance. Figure 3 is a schematic diagram of the microscopic cross-section of the existing roller metal crystal protrusion piercing the thin film substrate; Figure 4 is a microscopic schematic diagram of the protruding defects formed by the coating of metal particles falling off the existing roller. Figure 5 is a schematic diagram of the integral slotted and glued partitioned cathode conductive roller structure of Embodiment 1 of the present invention; Figure 6 is a cross-sectional view and assembly exploded view of the modular nested splicing cathode conductive roller shaft according to Embodiment 2 of the present invention; Figure 7 is a schematic diagram of the solid metal rod integrally formed cathode conductive roller structure of Embodiment 3 of the present invention; Figure 8 is a schematic diagram of the first structure of the single-end conductive cathode conductive roller shaft in Embodiment 4 of the present invention; Figure 9 is a schematic diagram of the second structure of the single-end conductive cathode conductive roller shaft in Embodiment 4 of the present invention; Figure 10 is a schematic diagram of the third structure of the single-end conductive cathode conductive roller shaft in Embodiment 4 of the present invention; Figure 11 is a schematic diagram of the full-surface flexible conductive coated roller structure of Embodiment 5 of the present invention; Figure 12 is a schematic diagram of the circuit arrangement of the first roll-to-roll electroplating equipment of the present invention (single anode with single-sided cathode conductive roller closed circuit). Figure 13 is a schematic diagram of the circuit arrangement of the second type of roll-to-roll electroplating equipment of the present invention (single anode with front and rear double-sided cathode conductive rollers closed circuit). In the figure: 1-rigid shaft, 2-end conductive area, 3-middle functional support area, 4-electrical connection part, 5-annular groove, 7-removable locking structure, 8-end bushing, 9-transmission gear shaft, 11-cathode conductive roller shaft, 12-anode assembly, 13-water-blocking roller shaft, 14-cathode plated object. Detailed Implementation

[0046] Example 1 like Figure 5 As shown, this embodiment provides a roll-to-roll electroplating cathode conductive roller shaft, including a rigid shaft body 1, an end conductive area 2, a middle functional support area 3, and an electrical connection part 4.

[0047] The rigid shaft 1 is a single hollow metal tube made of SUS316 stainless steel, which has good resistance to corrosion from electroplating solutions. The rigid shaft 1 has two axial ends and a middle section located between the two ends.

[0048] There are two end conductive regions 2, respectively located at both ends of the rigid shaft 1. The end conductive regions 2 are the uncut outer surface areas of the original metal tube at both ends of the rigid shaft 1, made of SUS316 stainless steel, used to contact the edge reserved area of ​​the material to be processed and conduct cathode potential. The surface of the end conductive regions 2 is polished, with a surface roughness of Ra 0.8μm.

[0049] A central functional support area 3 is located in the middle of the rigid shaft 1, between the two end conductive areas 2. The central functional support area 3 and the end conductive areas 2 are arranged adjacent to each other along the axial direction. The central functional support area 3 does not include the metal tube wall of the rigid shaft 1; it is formed by filling material into an annular groove 5 provided on the outer circumferential surface of the middle part of the rigid shaft 1. Specifically, the structure of the annular groove 5 is as follows: an annular groove 5 is formed by circumferential cutting on the outer circumferential surface of the middle part of the rigid shaft 1. The annular groove 5 is located axially between the two end conductive areas 2, and its axial width corresponds to the effective electroplating area width of the material to be processed. The cutting depth of the annular groove 5 is about 1 / 3 of the thickness of the metal tube wall of the rigid shaft 1, which is less than half the thickness of the metal tube wall, so that the rigid shaft 1 maintains sufficient mechanical bending strength after grooving. After turning, the bottom and sidewalls of the annular groove 5 are sandblasted to roughen the surface, with a surface roughness of Ra 6.3μm. Then, a silane coupling agent is applied as an interface primer. The silane coupling agent used is commercially available general rubber-metal silane coupling agent KH-550. After application, it is cured at room temperature for 15 minutes to improve the bonding strength between the subsequent filler material and the metal substrate.

[0050] After the annular groove 5 is processed, it is filled with an insulating, acid- and alkali-resistant flexible polymer material to form the central functional support area 3. This material is insulating and does not generate cathodic polarization during electroplating. In this embodiment, the insulating, acid- and alkali-resistant flexible polymer material is EPDM (ethylene propylene diene monomer rubber), with a cured Shore A hardness of 65°. The filling process employs a compression molding and vulcanization integrated molding process at 160°C and 6 MPa, ensuring a reliable bond between the rubber and the bottom and sidewalls of the annular groove 5, with a shear bond strength greater than or equal to 6 MPa. This reduces the risk of debonding or seepage during immersion in acid- and alkali-based electroplating solutions and high-tension reciprocating rolling. After filling and curing, no cathodic polarization occurs during electroplating, thus preventing surface metal deposition. The surface roughness of the central functional support area 3 is Ra 1.6 μm. Because EPDM has excellent acid and alkali resistance, the material does not swell, degrade, or deteriorate in performance when immersed in acidic or alkaline electroplating solutions for a long time, ensuring the long-term stable use of the roller in the electroplating solution environment.

[0051] In this embodiment, the end conductive area 2 and the middle functional support area 3 are the outer surface areas of different axial sections of the rigid shaft 1. After vulcanization and curing, the entire surface of the roller shaft is precision ground and polished using a precision cylindrical grinder. After polishing, the outer surface of the middle functional support area 3 is flush with the outer surface of the end conductive area 2, forming a continuous cylindrical support working surface. The overall coaxiality is 0.01 mm, the cylindricity is 0.01 mm, and the radial step difference at the junction of the middle functional support area 3 and the end conductive area 2 is 20 μm.

[0052] The electrical connection part 4 is a copper screw mechanism located on the axial end face of the rigid shaft 1. The electrical connection part 4 is electrically connected to the end conductive area 2 and is used to dynamically connect to an external cathode power supply via a mercury conductive slip ring assembly, introducing a negative potential into the roller shaft. Specifically, the copper screw mechanism of the electrical connection part 4 is tightly pressed against an interference-fitted solid stainless steel weight-reducing reinforcing liner. The liner and the inner wall of the rigid shaft 1 form a reliable electrical connection through an interference fit, thereby conducting the cathode potential to the end conductive area 2. The mercury conductive slip ring assembly features low conductivity and stable signal transmission, and can meet the current transmission requirements under high-speed roller shaft rotation conditions.

[0053] Solid stainless steel weight-reducing reinforcing rods are interference-fitted into both ends of the rigid shaft 1 to improve the structural strength of both ends of the shaft and reduce the overall weight of the roller. A transmission gear shaft position 9 is machined on the outer side of the rods for meshing with an external transmission mechanism to drive the roller to rotate around its axis. In this embodiment, the transmission gear shaft position 9 is a sector gear that meshes with an external sector gear for transmission. In actual implementation, any type of gear structure, such as a helical gear, spur gear, bevel gear, or worm gear, can be selected according to transmission requirements. The transmission gear shaft position 9 and the electrical connection part 4 are located at the same end.

[0054] In addition, an end bushing 8 made of PU material is provided on the axial outer side of the end conductive area 2, which is fitted on the outer side of the end conductive area 2 to reduce the contact of the bath liquid with the non-working conductive area, and to provide support, limit or isolate when the roller rotates.

[0055] In this embodiment, the cathode conductive roller shaft is connected to an external cathode power supply via a mercury conductive slip ring assembly during operation, introducing a negative potential into the roller shaft. Since the end conductive area 2 is made of SUS316 stainless steel and is electrically connected to the electrical connection unit 4, the negative potential is conducted to the surface of the end conductive area 2. The edge reserved area of ​​the film to be processed contacts the end conductive area 2 to obtain a cathode potential, which is then conducted to the entire film surface. The effective electroplating area of ​​the film is immersed in the electroplating solution, where metal ions gain electrons on the film surface, reducing and depositing to form a coating. During this process, the central functional support area 3 is made of an insulating, acid- and alkali-resistant flexible polymer material, which does not generate cathode polarization during electroplating. Therefore, metal ions in the electroplating solution will not be reduced and deposited on the surface of the central functional support area 3, thus avoiding the problems of metal particle shedding, film scratches, and particle encapsulation caused by surface metal deposition in traditional integral metal conductive rollers.

[0056] Example 2 like Figure 6 As shown, this embodiment provides a roll-to-roll electroplating cathode conductive roller shaft, the main difference from the first embodiment is that the end conductive area 2 and the middle functional support area 3 are functional sleeves fitted on the outside of the rigid shaft body 1.

[0057] The rigid shaft 1 is a centrally rigid, through-type main shaft. The end conductive areas 2 are two in number, each consisting of a first and a second metal conductive sleeve fitted at both ends of the central main shaft, both made of SUS316 stainless steel. The central functional support area 3 is an insulating sleeve fitted in the middle of the central main shaft, made of polyurethane (PU) with a Shore A hardness of 75°, and constructed entirely of an insulating, acid- and alkali-resistant flexible polymer material.

[0058] The insulating sleeve is composed of three sub-sleeves spliced ​​together axially. The perpendicularity of the axial mating end faces between each sub-sleeve is controlled to 0.008mm. A circumferential micro-chamfer with dimensions of 0.05mm × 45° is provided on the outer circumferential edge of the mating. The circumferential micro-chamfer is used to eliminate sharp edges at the splicing points of the sub-sleeves, preventing scratches on the substrate due to minor misalignment during film conveying. After assembly and tightening, the width of the axial splicing micro-gap between adjacent sub-sleeves is 0.008mm, reducing the risk of microscopic sharp corners piercing the film surface at the splicing gap. Disassembling the long insulating sleeve into multiple sub-sleeves also solves the problem of deformation and difficulty in drilling holes during precision CNC machining of ultra-long plastic bushings.

[0059] The metal conductive sleeve and the central spindle are fitted with an interference fit. The spindle diameter is 80mm, and the radial interference on one side is 0.04mm. This is achieved through a heat-fitting process where the entire metal sleeve is heated to 220°C and then fitted onto the spindle. The outer support working surfaces of both the metal conductive sleeve and the insulating sleeve have no exposed screws, locating pins, or fastening protrusions, maintaining a smooth surface to reduce the risk of friction and scratches caused by exposed fasteners or surface discontinuities on the extremely thin flexible film.

[0060] The central spindle is equipped with detachable locking structures 7 at both ends, including end locking bushings and anti-loosening retaining rings. A thrust is applied via axial clamping threads to secure all functional sleeve modules in the axial direction. If a section of the conductive or insulating sleeve experiences localized wear or corrosion during long-term use, the end clamping threads can be loosened, allowing the functional sleeves to slide out sequentially and be replaced individually. The central spindle and the remaining intact sleeves can be reused, reducing maintenance costs.

[0061] The outer surface of the central functional support area 3 is flush with the outer surface of the end conductive area 2, and together they form a continuous cylindrical support working surface after polishing. The rest of the structure is the same as in Embodiment 1.

[0062] The working principle of this embodiment is the same as that of Embodiment 1. The difference is that the end conductive area 2 and the middle functional support area 3 are not formed by the rigid shaft 1 itself, but are respectively formed by a metal conductive sleeve and an insulating sleeve fitted on the outside of the central main shaft. This modular structure allows each functional sleeve to be disassembled and replaced individually without replacing the entire roller shaft. In addition, the insulating sleeve is composed of three sub-sleeves spliced ​​together, which solves the problems of deformation and hole difficulty in precision machining of ultra-long plastic bushings. The mating end faces between each sub-sleeve are precision machined, and the width of the splice micro-seam after assembly is only 0.008mm. With the axial clamping force applied by the detachable locking structure 7, it is ensured that no indentation is left on the film surface at the splice.

[0063] Example 3 like Figure 7 As shown, this embodiment provides a roll-to-roll electroplating cathode conductive roller shaft, the main difference from embodiment one is that the rigid shaft 1 is an integral solid metal shaft bar.

[0064] The rigid shaft 1 is made of solid SUS316 stainless steel. There are two end conductive areas 2, which are the unmachined outer surfaces of the original metal cylinders at both ends of the solid metal cylinder, made of SUS316 stainless steel. A reduction groove is formed on the middle outer surface of the solid metal cylinder by CNC cutting. The reduction groove is located axially between the two end conductive areas 2.

[0065] After the diameter reduction groove is machined, a rubber-coating mold is fitted onto the outside of the groove, and EPDM soft rubber is filled into it using molding. This is then heat-cured to form the central functional support area 3. This central functional support area 3 is an insulating, acid- and alkali-resistant flexible polymer rubber-coated area cured within the diameter reduction groove. After curing, it undergoes precision polishing to make the outer surface of the central functional support area 3 flush with the outer surface of the end conductive area 2, forming a continuous cylindrical support working surface. The overall coaxiality can be controlled within 0.015mm. Compared to the hollow tube structure of Embodiment 1, this embodiment uses a solid metal rod integrally molded, exhibiting extremely high integrated rigidity and coaxiality, eliminating the accumulation of all internal assembly tolerances, resulting in high precision and low assembly cost, but with a relatively larger overall weight. The remaining structure is the same as in Embodiment 1.

[0066] The working principle of this embodiment is the same as that of Embodiment 1. The difference is that the rigid shaft 1 is a solid metal rod, not a hollow tube. The solid structure gives the roller shaft higher overall rigidity and less rotational inertia fluctuation. The overall coaxiality can be controlled within 0.015mm, the radial runout during roller shaft rotation is smaller, and the film conveyor belt is smoother. In addition, the diameter reduction groove is formed directly on a solid rod by CNC cutting, without the need for an additional liner, making the structure simpler.

[0067] Example 4 like Figures 8 to 10 As shown, this embodiment provides a roll-to-roll electroplating cathode conductive roller shaft, the main difference from the first embodiment is that: there is one end conductive area 2, which is set at one axial end of the rigid shaft body 1; the middle functional support area 3 extends axially to the end where the end conductive area 2 is not set.

[0068] Specifically, the area of ​​the roller surface other than the single-end conductive area is covered with EPDM material to form the central functional support area 3. The central functional support area 3 is made of an insulating, acid and alkali resistant flexible polymer material. After curing, it is flush with the outer surface of the end conductive area 2, and together they form a continuous cylindrical support working surface after polishing.

[0069] Figure 8 The structure with end conductive region 2 located at the left end is shown. Figure 9 The structure with end conductive region 2 located at the right end is shown. Figure 10 The diagram illustrates a structure where the end conductive region 2 is located in the middle, and the central functional support regions 3 are distributed on both sides. When applied to horizontal electroplating equipment, the end conductive region 2 can be located at the left or right end depending on the equipment layout; when applied to vertical electroplating equipment, the end conductive region 2 can be located at the top or bottom. This single-end conductive structure reduces conductive contact and exposed conductive area on one side, lowering the processing and assembly complexity in various application scenarios.

[0070] The transmission gear shaft 9 can be located at either end as needed, and can be located at the same end as the electrical connection part 4 or at two separate ends. The rest of the structure is the same as in Embodiment 1.

[0071] The working principle of this embodiment is similar to that of Embodiment 1, except that the film only needs to be in contact with the end conductive area 2 on one side edge to conduct electricity. The cathode potential is conducted from the single end conductive area 2 to the edge reserved area of ​​the film, and then along the film surface to the entire effective electroplating area. Since only one end conductive area 2 is provided, the other end of the roller is completely covered by the central functional support area 3, which reduces the exposed conductive area, reduces the risk of corrosion of the conductive area by the electroplating solution, and simplifies the assembly structure of the roller.

[0072] Example 5 like Figure 11 As shown, this embodiment provides a roll-to-roll electroplating cathode conductive roller shaft, the main difference from Embodiment 1 is that the central functional support area 3 is a flexible conductive support area.

[0073] The entire outer working surface of the roller is covered with an acid- and alkali-resistant flexible conductive polymer layer, forming the central functional support area 3. This flexible conductive polymer layer is formed by mixing EPDM with conductive carbon black; EPDM provides acid and alkali resistance and flexibility, while the conductive carbon black provides conductivity. The surface resistance of this flexible conductive polymer layer is less than 10³ Ω / □, enabling it to conduct cathode potential. The rigid shaft 1 of the roller is made of SUS316 stainless steel tubing.

[0074] This structure transforms the traditional hard metal roller surface conductive contact into a flexible conductive contact, reducing the risk of scratches caused by differences in synchronization or surface hardness between the hard metal roller surface and the thin film material while ensuring cathode conductivity. The remaining structure is the same as in Example 1.

[0075] The working principle of this embodiment differs from that of Embodiment 1. In Embodiments 1 to 4, the central functional support region 3 is a non-conductive support region, and the cathode potential is conducted to the edge reserved area of ​​the film only through the end conductive region 2. In this embodiment, the central functional support region 3 itself is a flexible conductive material, and the effective electroplating area of ​​the film can directly obtain the cathode potential from the central functional support region 3 without relying on the edge reserved area for conduction. The flexible conductive polymer layer is formed by mixing EPDM with conductive carbon black. EPDM provides flexibility and acid and alkali resistance, while the conductive carbon black forms a conductive network in the EPDM matrix, making the material as a whole conductive. The surface resistance is less than 10³Ω / □, which can meet the cathode conductivity requirements of the electroplating process. At the same time, since the roller surface is a flexible material, the film and the roller surface are in flexible contact, avoiding the risk of scratches caused by hard metal roller surfaces.

[0076] Example 6 This embodiment provides a method for manufacturing the roll-to-roll electroplated cathode conductive roller shaft described in Embodiment 1, including the following steps: S1: Select a SUS316 stainless steel hollow tube as the rigid shaft 1, with an outer diameter of 80mm, a wall thickness of 8mm, and a length of 600mm. Based on the effective electroplating area width of 500mm for the material to be processed and the reserved width of 15mm on each side edge, determine the length of the rigid shaft 1 to be 600mm. The outer surface of the original metal tube at each end of the rigid shaft 1, with a width of 15mm, is left unmachined and retained as the end conductive area 2. The two end conductive areas 2 are located at the axial ends of the rigid shaft 1 and are made of SUS316 stainless steel.

[0077] S2: On the outer circular surface of the middle part of the rigid shaft 1, within a range of 500mm extending from 15mm from one end towards the other end, an annular groove 5 is formed by CNC machining along the circumferential direction. The axial width of the annular groove 5 is 500mm, and the cutting depth is 2.5mm, which is less than half of the 8mm thickness of the metal tube wall. The annular groove 5 is located axially between the two end conductive areas 2. After turning, the bottom surface and sidewalls of the annular groove 5 are sandblasted to achieve a surface roughness of Ra 6.3μm. Then, a silane coupling agent is applied as an interface primer. The silane coupling agent used is a commercially available general-purpose rubber-metal silane coupling agent KH-550. After application, it is cured at room temperature for 15 minutes to enhance the adhesion strength between the rubber and the metal.

[0078] S3: Place the rigid shaft 1, after primer treatment, into the mold, and fill the annular groove 5 with EPDM (ethylene propylene diene monomer rubber). Use a compression molding and vulcanization process for encapsulation and curing. The vulcanization temperature is 160°C, the pressure is 6 MPa, and the curing time is 30 minutes. After curing in the annular groove 5, the EPDM forms an insulating, acid- and alkali-resistant flexible polymer material layer, serving as the central functional support area 3. The Shore A hardness of the central functional support area 3 is 65°, and the shear bond strength between it and the metal substrate is greater than or equal to 6 MPa. The central functional support area 3 is made by curing and filling with EPDM insulating, acid- and alkali-resistant flexible polymer material.

[0079] S4: The outer surfaces of the end conductive area 2 and the middle functional support area 3 are ground using a precision cylindrical grinder, and then polished. After polishing, the outer surface of the middle functional support area 3 is flush with the outer surface of the end conductive area 2, forming a continuous cylindrical support working surface. The overall coaxiality reaches 0.01 mm, the cylindricity reaches 0.01 mm, and the radial step difference at the junction of the middle functional support area 3 and the end conductive area 2 is 20 μm. The surface roughness of the end conductive area 2 is Ra 0.8 μm, and the surface roughness of the middle functional support area 3 is Ra 1.6 μm.

[0080] S5: Solid stainless steel weight-reducing reinforcing bushings are interference-fitted into the interior of both ends of the rigid shaft 1, and transmission gear shaft positions 9 are machined on the outer side of the bushings. Simultaneously, a copper screw mechanism is installed on the axial end face of the rigid shaft 1 as an electrical connection part 4. The electrical connection part 4 is electrically connected to the end conductive area 2 for dynamic electrical connection with the mercury conductive slip ring assembly. The copper screw mechanism of the electrical connection part 4 is tightly pressed against the interference-fitted solid stainless steel weight-reducing reinforcing bushings. The bushings achieve a reliable electrical connection with the inner wall of the rigid shaft 1 through the interference fit, thereby stably transmitting the cathode potential to the end conductive area 2. The transmission gear shaft position 9 and the electrical connection part 4 are located at the same end. An end bushing 8 made of PP material is fitted onto the axial outer side of the end conductive area 2.

[0081] Thus, the roll-to-roll electroplating cathode conductive roller shaft described in Example 1 has been manufactured.

[0082] Example 7 As shown in Figures 12 and 13, this embodiment provides a roll-to-roll fluid electroplating equipment, including an electroplating tank, an anode assembly 12, a DC rectifier, a conductive slip ring assembly, a cathode conductive roller shaft 11 as described in any one of embodiments one to five, and a water-blocking roller shaft 13, for guiding the conveyor path of the cathode plated object 14.

[0083] The electroplating tank is a rectangular prism with an opening at the top for holding the electroplating solution. An inlet is located on the upper part of the side wall, and a drain is located on the lower part of the side wall for circulating and filtering the electroplating solution. The anode assembly 12 is a plate-shaped structure, placed inside the electroplating tank and immersed in the electroplating solution, and electrically connected to the anode output terminal of the DC rectifier.

[0084] The cathode conductive roller shaft 11 is positioned above the electroplating tank and mounted on the side wall of the tank via bearing seats at both ends. The conductive slip ring assembly is a mercury conductive slip ring assembly, with one end dynamically connected to the electrical connection part 4 of the cathode conductive roller shaft 11 and the other end electrically connected to the cathode output terminal of the DC rectifier. The conductive slip ring assembly is electrically connected to the electrical connection part 4 via a copper screw mechanism. The DC rectifier is located outside the electroplating tank and is used to convert alternating current to direct current, providing anode and cathode potentials to the anode assembly 12 and the cathode conductive roller shaft 11, respectively.

[0085] In this embodiment, the electroplating equipment converts alternating current (AC) to direct current (DC) using a DC rectifier. The anode output provides a positive potential to the anode assembly 12, while the cathode output provides a negative potential to the electrical connection part 4 of the cathode conductive roller 11 via a conductive slip ring assembly. The film to be processed continuously passes through the cathode conductive roller 11 and the electroplating tank under the traction of the unwinding and rewinding mechanisms. The edge pre-reserved area of ​​the film contacts the end conductive area 2 to obtain a cathode potential. The effective electroplating area of ​​the film is immersed in the electroplating solution. Metal ions in the electroplating solution gain electrons on the film surface, reducing and depositing to form a coating. The anode assembly 12 conducts electricity in the electroplating solution and maintains a stable electroplating electric field. The electroplating solution system continuously replenishes the consumed metal ions through an external replenishment system to maintain the balance of the plating solution composition.

[0086] Figure 12 shows the assembly configuration where the upper and lower sets of cathode conductive rollers 11 correspond to the upper and lower anode assemblies 12 of a set of electroplating tanks to form a closed loop; Figure 13 shows the assembly configuration where the upper and lower anode assemblies 12 of a set of electroplating tanks correspond to the two sets of cathode conductive rollers 11 to form a closed loop. These two assembly configurations can be selected according to different process requirements to achieve single-sided or double-sided electroplating.

[0087] Example 8 This embodiment provides a roll-to-roll electroplating method, using the roll-to-roll fluid electroplating equipment described in Embodiment 7 and the cathode conductive roller shaft described in any one of Embodiments 1 to 5, including the following steps: S1: Determine the axial width of the end conductive area 2 and the axial width of the middle functional support area 3 based on the effective electroplating area width of the material to be processed and the subsequent cutting edge width.

[0088] The material to be processed is a PET film with a thickness of 50μm and a width of 530mm. The effective electroplating area of ​​the product is 500mm wide, and the width of the reserved area on both sides is 15mm. Therefore, the axial width of the central functional support area 3 is determined to be 500mm, and the axial width of the two end conductive areas 2 is 15mm each.

[0089] S2: The cathode conductive roller shaft is installed above the electroplating tank. An anode assembly is installed inside the electroplating tank and is electrically connected to the anode output terminal of a DC rectifier. The electrical connection part 4 of the cathode conductive roller shaft is electrically connected to the cathode output terminal of the DC rectifier via a mercury conductive slip ring assembly. The electroplating tank contains a copper sulfate electroplating solution with a copper ion concentration of 60 g / L and a sulfuric acid concentration of 100 g / L. The solution temperature is 25°C. The electroplating solution flows in from the inlet and out from the outlet via a circulation pump, and is filtered before being recycled.

[0090] S3: Guide the material to be processed through the cathode conductive roller shaft, control the width or conveyor position of the material to be processed, so that the edge reserved area of ​​the material to be processed contacts the end conductive area 2, and the effective electroplating area of ​​the material to be processed contacts the middle functional support area 3.

[0091] The PET film roll is mounted on the unwinding mechanism, and the film is guided to the cathode conductive roller shaft by the guide roller. The film feeding position is adjusted so that the 15mm wide edge reserved areas on both sides of the film contact the end conductive areas 2 at both ends of the cathode conductive roller shaft, and the 500mm wide effective electroplating area in the middle of the film contacts the central functional support area 3. The film is partially immersed in the electroplating solution in the electroplating tank. The feeding speed is 2m / min, and the feeding tension is 50N.

[0092] S4: A cathode potential is applied to the end conductive area 2 through the electrical connection part 4, and metal ions in the electroplating solution are reduced and deposited on the surface of the material to be treated to form a coating.

[0093] A cathode potential is applied to the electrical connection part 4 via a mercury conductive slip ring assembly and a copper screw mechanism, with a current density of 2 A / dm². The end conductive region 2 conducts the cathode potential to the edge reserved area of ​​the film, and then to the entire film surface. Copper ions in the electroplating solution gain electrons on the film surface, reducing and depositing to form a copper plating layer with a thickness of 8 μm.

[0094] The working principle of this embodiment is as follows: During the electroplating process, the DC rectifier provides a negative potential to the end conductive region 2 through the conductive slip ring assembly and the electrical connection part 4. The end conductive region 2 contacts the edge reserved area of ​​the thin film, conducting the negative potential to the surface of the thin film. The effective electroplating area of ​​the thin film is immersed in the electroplating solution. Copper ions in the electroplating solution gain electrons on the surface of the thin film, are reduced to metallic copper, and are deposited to form a coating. At the same time, the anode assembly completes conduction in the electroplating solution and maintains the stability of the electroplating electric field. The electroplating solution system continuously replenishes the consumed copper ions through an external replenishment system to maintain the stability of the electroplating solution concentration.

[0095] When using the cathode conductive rollers described in Examples 1 to 4, during the electroplating process, the central functional support area 3 is a non-conductive support area, which does not generate cathode polarization and has no metal deposition on its surface. The central functional support area 3 is made of an insulating, acid and alkali resistant flexible polymer material, which flexibly contacts the effective electroplating area of ​​the film, reducing the risk of scratches caused by synchronous differences or surface hardness differences between the traditional hard metal roller surface and the film.

[0096] When using the cathode conductive roller shaft described in Example 5, during the electroplating process, the central functional support area 3 is a flexible conductive support area, which is made of an insulating, acid and alkali resistant, flexible conductive polymer material. It makes flexible conductive contact with the effective electroplating area of ​​the thin film, and the thin film obtains a cathode potential through the central functional support area 3. Since the roller surface is made of a flexible material, the risk of scratches caused by traditional hard metal roller surfaces is also reduced.

[0097] S5: After electroplating is completed, the edge reserved area that contacts the end conductive area 2 is cut or removed, and the effective electroplating area is retained.

[0098] After electroplating, the roll is removed from the winding mechanism and dried. In the subsequent slitting process, the 15mm wide edge reserved areas on both sides of the film are slit and removed, leaving a 500mm wide effective electroplating area in the middle to obtain the final product.

[0099] Under continuous electroplating conditions producing 1000 meters of film, the effective electroplating area of ​​the film after electroplating was examined under a microscope at a magnification of 200x, with an inspection area of ​​100mm × 100mm. When the cathode conductive roller described in Example 1 was used, the test results showed that no scratches or metal particle coating defects were found in the effective electroplating area, and the overall product yield was 98.2%. This is because the central functional support area 3 is made of EPDM insulating acid and alkali resistant flexible polymer material, which does not generate cathode polarization during the electroplating process, has no metal deposition on the surface, and has flexible contact with the film, thus avoiding scratches and metal particle coating problems caused by hard metal roller surfaces from the source.

[0100] When using the cathode conductive roller shaft described in Example 2, the central functional support area 3 is composed of an insulating sleeve fitted into the center of the main shaft. The insulating sleeve is made of polyurethane (PU), which is also made of an insulating, acid- and alkali-resistant flexible polymer material. It does not generate cathode polarization during electroplating, and there is no metal deposition on its surface. The insulating sleeve is composed of three sub-sleeves spliced ​​together. The perpendicularity of the mating end faces between each sub-sleeve is controlled to 0.008 mm, and the mating edges are provided with circumferential micro-chamfers. The width of the splicing micro-seam is only 0.008 mm, leaving no indentation on the film surface. Under the condition of continuous electroplating production of 1000 meters of film, the overall product yield is 98.1%.

[0101] When using the cathode conductive roller shaft described in Example 3, the rigid shaft 1 is a solid metal shaft, and the central functional support area 3 is an insulating, acid- and alkali-resistant flexible polymer coating area solidified within the diameter-reducing groove, which is made of EPDM. The overall coaxiality can be controlled within 0.015mm, resulting in less radial runout during roller rotation and smoother film feeding. Under continuous electroplating production of 1000 meters of film, the overall product yield is 98.5%.

[0102] When using the cathode conductive roller shaft described in Example 4, an end conductive region 2 is provided only at one end of the rigid shaft 1. The film only needs to be in contact with the conductive region on one side edge to conduct electricity. The electroplating method steps are the same as described above, except that in S3, only the reserved area on one side edge of the film needs to be in contact with the end conductive region 2. Under the condition of continuous electroplating to produce 1000 meters of film, the overall product yield is 98.0%.

[0103] When using the cathode conductive roller shaft described in Example 5, during the electroplating process, the central functional support area 3 is a flexible conductive support area, which is made of acid and alkali resistant flexible conductive polymer material. It makes flexible conductive contact with the effective electroplating area of ​​the thin film, and the thin film obtains cathode potential through the central functional support area 3. Since the roller surface is made of flexible material, the risk of scratches caused by traditional hard metal roller surfaces is also reduced.

[0104] Example 9 This embodiment provides an improved solution for the detachable locking structure 7 used in the roll-to-roll electroplating cathode conductive roller shaft described in Embodiment 2. This improved solution is mainly used to maintain the continuous axial clamping force of the detachable locking structure 7 on each functional sleeve when the multiple sub-sleeves of the insulating sleeve undergo slight axial dimensional changes due to temperature variations, long-term pressure creep, or immersion in the electroplating solution.

[0105] A superelastic compensation ring is provided between the end locking bushing and the anti-loosening retaining ring of the detachable locking structure 7. The superelastic compensation ring is preferably a wave-shaped annular spring or a disc-shaped annular spring, rather than a flat, thick ring structure, to provide recoverable elastic compensation displacement within a small axial installation space. The superelastic compensation ring has an outer diameter of 60 mm, an inner diameter of 50 mm, a base thickness of 0.8-1.2 mm, and an axial wave height or disc height in the free state of 1.2-1.8 mm. In this embodiment, the superelastic compensation ring specifically adopts a disc-shaped annular spring with a base thickness of 1.0 mm and a disc height in the free state of 1.5 mm. The superelastic compensation ring is made of a titanium-nickel shape memory alloy with a nickel content of 50.6 at%-51.0 at%, and its austenitic phase transformation end temperature Af is -20°C to 0°C, allowing it to remain in the austenitic phase and possess superelastic recovery capability at an electroplating solution operating temperature of 25°C. In this embodiment, the hyperelastic compensation ring is specifically made of titanium-nickel shape memory alloy with a nickel content of 50.8 at%, and its austenitic phase transformation end temperature Af is -15°C. During assembly, the hyperelastic compensation ring is pre-compressed by 0.4-0.8 mm, corresponding to an axial preload of 3000-5000 N. The pre-compression displacement is mainly absorbed by the bending deformation of the waveform or disc structure, and the maximum equivalent strain in the working area of ​​the compensation ring is controlled within 5%. In this embodiment, the pre-compression is 0.6 mm, corresponding to an axial preload of 4000 N.

[0106] The manufacturing process of the superelastic compensation ring is as follows: A titanium-nickel alloy ingot is prepared by vacuum induction melting, and then hot-forged, hot-rolled, or cold-rolled into a plate or strip. A ring-shaped blank is then formed by wire cutting, laser cutting, or precision punching. Subsequently, the ring-shaped blank is deburred, polished, and surface-cleaned, and then shaped into a wave or dish shape in a special shaping fixture. The shaping temperature is 450°C-520°C, and the holding time is 10-30 minutes, followed by air cooling or furnace cooling to achieve a stable superelastic working shape for the compensation ring. In this embodiment, the shaping temperature is 480°C, the holding time is 20 minutes, and then furnace cooling is performed. After shaping, 20 load-unload cycles are performed at room temperature, with the loading range corresponding to the actual assembly compression displacement, to stabilize its axial restoring force. After 100,000 loading cycles, the residual deformation of the trained superelastic compensation ring does not exceed 0.2%.

[0107] To prevent corrosion of the titanium-nickel alloy compensation ring in acidic or alkaline electroplating environments, the surface of the superelastic compensation ring is provided with an acid- and alkali-resistant elastic isolation coating. The acid- and alkali-resistant elastic isolation coating is preferably a composite coating of a parylene (e.g., Parylene C) layer and a fluoropolymer layer. The parylene (e.g., Parylene C) layer is formed on the surface of the compensation ring by vapor deposition, with a thickness of 2-5 μm, to improve the continuity and adhesion of the coating. The fluoropolymer layer is one of FEP (perfluoroethylene propylene copolymer), PFA, ETFE, or PTFE, with a thickness of 10-30 μm, to provide acid and alkali corrosion resistance and low surface energy. The composite coating does not produce through-cracks under 3%-5% cyclic bending strain conditions and can maintain isolation and protection of the titanium-nickel alloy substrate during repeated compression and springback of the compensation ring. In this embodiment, the parylene layer is specifically Parylene C, formed by vacuum vapor deposition. The deposition chamber pressure is 5 Pa, the evaporation chamber temperature is 165°C, the pyrolysis chamber temperature is 680°C, the deposition time is 45 minutes, and the resulting coating thickness is 3 μm. The fluoropolymer layer is specifically prepared by plasma deposition: after the Parylene C layer deposition is completed, a mixture of perfluoroethylene and propylene gas is introduced into the same vacuum deposition chamber. The fluoropolymer layer is directly polymerized and deposited on the surface of the Parylene C layer through plasma activation. The deposition chamber pressure is 3 Pa, the plasma power is 200 W, the deposition time is 30 minutes, and the resulting fluoropolymer layer thickness is 15 μm.

[0108] To prevent the superelastic compensation ring from forming a current bypass, an insulating gasket is provided between the compensation ring and the adjacent metal locking component. The insulating gasket is preferably an alumina ceramic gasket or a zirconia ceramic gasket, disposed between at least one axial end face of the compensation ring and the adjacent metal component; more preferably, insulating gaskets are disposed between both axial end faces of the compensation ring and the adjacent metal component. The alumina ceramic gasket is an annular thin sheet with an outer diameter of 60 mm, an inner diameter of 50 mm, and a thickness of 0.5 mm, made of alumina ceramic with a purity of not less than 99.5% and a resistivity greater than 10^14 Ω·cm. In this embodiment, specifically, alumina ceramic gaskets, made of alumina ceramic with a purity of 99.5%, are disposed between both axial end faces of the compensation ring and the adjacent metal component.

[0109] The working principle of this embodiment is as follows: In Embodiment 2, multiple insulator sleeves are kept in contact by the axial clamping force applied by the detachable locking structure 7. During long-term operation, the axial length of the insulator sleeves may change slightly due to changes in the temperature of the electroplating solution, creep of the sleeve material, and repeated start-stop of the roller. If the locking structure does not have compensation capability, the axial clamping force will gradually decrease, and the micro-gap between the sleeves may widen, leading to the electroplating solution seeping in and corroding the central main shaft.

[0110] With the superelastic compensation ring of this embodiment, when the insulator sleeve undergoes slight expansion due to temperature rise, the compensation ring further compresses and absorbs the expansion displacement; when the insulator sleeve undergoes slight contraction due to long-term creep, the compensation ring rebounds using its superelastic recovery capability to compensate for the contraction gap. During this process, the compensation ring can maintain a relatively stable axial thrust within a certain stroke range, keeping the micro-gap between the sub-sleeves within a range not exceeding 0.01 mm, thereby reducing the risk of electroplating solution seeping into the central spindle along the joint.

[0111] Meanwhile, the acid and alkali resistant elastic insulating coating on the surface of the compensation ring remains intact during repeated compression and rebound, preventing the electroplating solution from directly contacting the titanium-nickel alloy substrate and causing nickel ion precipitation or pitting corrosion. The insulating gasket placed between the compensation ring and the adjacent metal locking component can block the bypass current, preventing some of the cathode current from being diverted through the locking structure or the central spindle, thus ensuring a more stable current distribution on the thin film surface during electroplating.

[0112] To verify the technical effectiveness of this embodiment, a long-term comparative experiment was conducted. The experimental conditions were as follows: the electroplating solution was copper sulfate solution with a copper ion concentration of 60 g / L, a sulfuric acid concentration of 100 g / L, and a temperature of 25°C; the roller speed was 60 r / min, the film conveyor belt speed was 2 m / min, and the belt tension was 50 N; the cumulative length of the electroplated film was 100,000 meters.

[0113] Group A consists of rollers using the scheme of this embodiment, which are equipped with a titanium-nickel alloy super-elastic compensation ring, an acid and alkali resistant elastic isolation coating, and an insulating gasket.

[0114] Group B is the original design of the roller shaft in Example 2, which means that the super-elastic compensation ring is not set in the detachable locking structure 7.

[0115] Group C is based on Group A, but with the acid and alkali resistant elastic isolation coating removed.

[0116] Group D replaces the acid and alkali resistant elastic barrier coating with a conventional hard ceramic coating, based on the method used in Group A.

[0117] Group E removes the insulating pad from Group A, allowing the compensating ring to make direct contact with the adjacent metal locking component.

[0118] Experimental results show that after accumulating 100,000 meters of electroplated film, the axial clamping force retention rate of Group A rollers is greater than 95%, the width of the splicing micro-seam is kept below 0.01 mm, there are no obvious corrosion marks on the surface of the central main shaft, there are no through cracks on the surface of the acid and alkali resistant elastic isolation coating, the coaxiality of the roller surface is kept at 0.01 mm, and the film current is stable during the electroplating process without abnormal fluctuations.

[0119] After accumulating 100,000 meters of electroplated film, the axial clamping force of the B group rollers significantly decreased, the width of the splicing micro-seams expanded to 0.05-0.08 mm, local corrosion marks appeared on the central main shaft at the corresponding position of the splice, and the coaxiality of the roller surface deteriorated.

[0120] After accumulating 100,000 meters of electroplated film, the axial clamping force of the C group rollers remained good, but pitting corrosion marks appeared on the surface of the compensation ring, and trace amounts of nickel ions were detected in the electroplating solution, indicating that the titanium-nickel alloy substrate is at risk of corrosion when there is no protective isolation coating.

[0121] After accumulating 100,000 meters of electroplated film, the axial clamping force of the D group rollers remained good, but microcracks and local peeling appeared on the surface of the conventional hard ceramic coating, indicating that the ordinary hard coating is difficult to adapt to the periodic deformation of the superelastic compensation ring in the long term.

[0122] After accumulating 100,000 meters of electroplated film, the axial clamping force of the E-group rollers remained good, and the width of the splice seams remained no more than 0.01 mm. However, periodic fluctuations in the film current occurred during the electroplating process. Inspection revealed that direct contact between the compensation ring and adjacent metal locking components created an unexpected current bypass, causing some of the cathode current to be diverted through the locking structure or the central main shaft. This demonstrates the essential role of insulating gaskets in maintaining a stable current path.

[0123] Therefore, this embodiment, through the combination of a super-elastic compensation ring, an acid and alkali resistant elastic isolation coating, and an insulating gasket, improves the long-term pre-tightening stability, electroplating solution corrosion resistance, and current path stability of the detachable locking structure 7 without changing the modular sleeve structure of Embodiment 2. This is beneficial to further reduce the impact of splicing micro-seam expansion, central spindle corrosion, and electroplating current fluctuations on product yield.

Claims

1. A roll-to-roll electroplating cathode conductive roller characterized in that, include: Rigid shaft (1); An end conductive region (2) is provided at least one end of the rigid shaft (1), and the end conductive region (2) is made of a conductive metal material; The central functional support area (3) is located in the middle of the rigid shaft (1) and is used to support the effective electroplating area of ​​the material to be processed. The central functional support area (3) is made of acid and alkali resistant flexible polymer material. The Shore A hardness of the flexible polymer material after curing is 40°~90°. The electrical connection part (4) is electrically connected to the end conductive area (2) and is used to connect to an external cathode power supply; The end conductive area (2) and the middle functional support area (3) are arranged adjacent to each other along the axial direction, and their outer surfaces are flush or nearly flush. After polishing or grinding, they together form a continuous cylindrical support working surface.

2. The roll-to-roll electroplating cathode conductive roll shaft according to claim 1, wherein, The rigid shaft (1) is an integral metal hollow tube, the end conductive area (2) is the original outer surface of the metal tube at both ends of the integral metal hollow tube that has not been cut, the middle outer surface of the integral metal hollow tube is provided with an annular groove (5), and the middle functional support area (3) is an insulating acid and alkali resistant flexible polymer coating layer filled, covered or solidified in the annular groove (5).

3. The roll-to-roll electroplating cathode conductive roller shaft according to claim 1, characterized in that, The rigid shaft (1) is an integral solid metal shaft, the end conductive area (2) is the original metal outer circle surface at both ends of the integral solid metal shaft that has not been machined, the middle outer circle surface of the integral solid metal shaft is provided with a diameter reduction groove, and the middle functional support area (3) is an insulating acid and alkali resistant flexible polymer coating area that is injection molded, molded or coated and cured in the diameter reduction groove.

4. The roll-to-roll electroplating cathode conductive roller shaft according to claim 1, characterized in that, The rigid shaft (1) is the central spindle, the end conductive area (2) is composed of a metal conductive sleeve fitted on the end of the central spindle, and the middle functional support area (3) is composed of an insulating sleeve fitted on the middle of the central spindle.

5. The roll-to-roll electroplating cathode conductive roller shaft according to claim 1, characterized in that, The end conductive area (2) consists of two parts, which are respectively located on both sides of the central functional support area (3) along the axial direction.

6. The roll-to-roll electroplating cathode conductive roller shaft according to claim 1, characterized in that, The end conductive area (2) is one, and the middle functional support area (3) extends axially to the end where the end conductive area (2) is not provided.

7. A method for manufacturing a roll-to-roll electroplated cathode conductive roller shaft as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1: Form an end conductive region (2), such that the end conductive region (2) is disposed at at least one end of the rigid shaft (1) and is made of conductive metal material; S2: Form a central functional support area (3), and set the central functional support area (3) in the middle of the rigid shaft (1) to support the effective electroplating area of ​​the material to be processed. The central functional support area (3) is made of acid and alkali resistant flexible polymer material. The Shore A hardness of the flexible polymer material after curing is 40°~90°, and the central functional support area (3) and the end conductive area (2) are arranged adjacent to each other along the axial direction. S3: Polish, grind or precision assemble the outer surfaces of the end conductive area (2) and / or the middle functional support area (3) so that the outer surfaces of the two together form a continuous cylindrical support working surface.

8. A roll-to-roll electroplating method, using a roll-to-roll electroplating cathode conductive roller as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1: Based on the effective electroplating area width of the material to be processed and the subsequent cutting edge width, determine the axial width of the end conductive area (2) and the axial width of the middle functional support area (3). S2: Guide the material to be processed through the cathode conductive roller shaft, control the width or conveyor position of the material to be processed, so that the edge reserved area of ​​the material to be processed contacts the end conductive area (2), and the effective electroplating area of ​​the material to be processed contacts or is set opposite to the middle functional support area (3). S3: A cathode potential is applied to the end conductive area (2) through the electrical connection part (4), and metal ions in the electroplating solution are reduced and deposited on the surface of the material to be treated to form a coating; S4: After electroplating is completed, the edge reserved area that is in contact with the end conductive area (2) is cut or removed, and the effective electroplating area is retained.

9. A roll-to-roll fluid electroplating apparatus, characterized in that, include: Electroplating tank; An anode assembly is disposed within the electroplating tank; A DC rectifier has an anode output terminal and a cathode output terminal, wherein the anode output terminal is electrically connected to the anode assembly; Conductive slip ring assembly; And the roll-to-roll electroplating cathode conductive roller shaft according to any one of claims 1 to 6, wherein the cathode conductive roller shaft is disposed above the electroplating tank, or the cathode conductive roller shaft is partially disposed within the electroplating tank; One end of the conductive slip ring assembly is dynamically electrically connected to the electrical access part (4) of the cathode conductive roller shaft, and the other end is electrically connected to the cathode output end of the DC rectifier.

10. The roll-to-roll fluid electroplating equipment according to claim 9, characterized in that, The conductive slip ring assembly is a mercury conductive slip ring assembly, which is electrically connected to the electrical connection part (4) of the cathode conductive roller shaft through a copper screw mechanism.

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