Long copper roller plating device capable of preventing reverse plating of conductive roller

Abstract

The invention relates to a long copper roller plating device capable of preventing reverse plating of a conductive roller, which belongs to the technical field of water electroplating and comprises a plurality of electroplating baths sequentially arranged along the advancing path of a composite copper film, and a conductive mechanism is arranged between every two adjacent electroplating baths. The conductive mechanism is composed of a first conductive roller, a second conductive roller, a first pressing roller and a second pressing roller, the first pressing roller and the second pressing roller are correspondingly arranged, and when the composite copper film sequentially penetrates through the first clamping area and the second clamping area, the first pressing roller and the second pressing roller exert positive pressure on the first conductive roller and the second conductive roller respectively. The positive pressure enables a pressing roller made of an elastic material to generate elastic deformation, a high-pressure sealing belt is formed in a clamping area, through the synergistic effect of the pressing roller and a conductive roller and film path control, plating solution retention is physically eliminated, an electric contact interface with zero potential difference is established, and therefore the chemical condition of reverse plating is fundamentally blocked.

Description

Technical Field

[0001] This invention relates to the field of electroplating technology, and more specifically, to a device for preventing reverse plating of conductive rollers with long copper rollers. Background Technology

[0002] In the traditional V-shaped electroplating process for PET composite copper film, the following methods are often used: Figure 3 The equipment layout shown depicts a composite copper film forming a large wrap angle at the conductive roller, typically greater than 100°. This causes the plating solution carried out of the plating bath by the film to accumulate within the wrap angle region, forming a residual plating solution film. Figure 4 As shown, the residual solution contains a large number of positively charged free copper ions. Due to the presence of the residual plating solution, the actual contact between the composite copper film and the conductive roller is poor, resulting in a significant potential difference between them. Driven by this potential difference, copper ions gain electrons from the surface of the conductive roller, undergoing an electrochemical reduction reaction to generate metallic copper, which gradually deposits and adheres to the surface of the conductive roller, such as... Figure 5 As production continues, the copper layer on the surface of the conductive roller thickens. The thicker the copper layer, the greater the contact resistance between the film and the roller, and the greater the potential difference. This accelerates the deposition rate of copper on the conductive roller, creating a vicious cycle. When the potential difference reaches a certain level, the copper layer already plated on the PET film may even act as a soluble anode, undergoing reverse ionization and dissolution to generate copper ions. This results in uneven coating thickness, decreased adhesion, and increased surface roughness, seriously affecting product qualification rate and production stability.

[0003] In practice, although measures such as increasing film tension, adding pressure rollers, and optimizing the plating bath discharge and cutting device can be taken to reduce residual liquid, the inherent limitations of the wrap-around structure mean that plating solution can never be completely avoided between the film and the conductive roller. As long as plating solution is present, the resulting potential difference and the series of electrochemical side reactions cannot be completely eliminated. Therefore, the existing V-shaped electroplating process always faces technical bottlenecks in continuous production, such as copper plating on the conductive roller, fluctuations in plating quality, and poor process stability, which restricts capacity improvement and product consistency assurance.

[0004] Therefore, there is an urgent need for a device to prevent the reverse plating of conductive rollers with long copper rollers, in order to solve the above technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide a device for preventing reverse plating of conductive rollers with long copper rollers, thereby solving the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A device for preventing reverse plating of long copper rollers using conductive rollers includes multiple electroplating tanks arranged sequentially along the travel path of a composite copper film. Each electroplating tank contains an anode mechanism uniformly immersed in a plating solution and an underwater roller for guiding the composite copper film. A conductive mechanism is provided between adjacent electroplating tanks. The conductive mechanism includes a rotatable first conductive roller, a second conductive roller, a first pressure roller, and a second pressure roller. The first pressure roller is positioned opposite to the first conductive roller, and the second pressure roller is positioned opposite to the second conductive roller, thereby forming a first clamping area and a second clamping area respectively as the composite copper film passes through. The composite copper film has an A side and a B side facing away from each other, and passes through the first clamping area and the second clamping area in sequence. The roller surfaces of the first conductive roller and the second pressure roller are in contact with the A side of the composite copper film, and the roller surfaces of the second conductive roller and the first pressure roller are in contact with the B side of the composite copper film. The first pressure roller and the second pressure roller apply positive pressure to the first conductive roller and the second conductive roller respectively, so that the composite copper film forms a liquid-free linear-surface sealed contact with the first conductive roller and the second conductive roller in the first clamping area and the second clamping area respectively.

[0007] As a preferred technical solution of the present invention, a tension mechanism is further provided between two adjacent electroplating tanks. The tension mechanism is located on the upstream side of the conductive mechanism along the traveling direction of the composite copper film, and is used to guide the composite copper film entering the conductive mechanism so that the composite copper film enters the first clamping area and the second clamping area tangentially.

[0008] As a preferred technical solution of the present invention, the tension mechanism includes a rotatable tension roller and a guide roller. The tension roller is disposed near the output end of the preceding electroplating tank and is used to change the direction of the composite copper film and provide tension. The guide roller is disposed near the input end of the following electroplating tank.

[0009] As a preferred technical solution of the present invention, the conductive mechanism and the tension mechanism are both disposed above the electroplating tank, wherein the highest generatrix of the tension roller and the highest generatrix of the roller are located on a first horizontal reference plane, and the lowest generatrix of the first conductive roller and the highest generatrix of the second conductive roller are located on a second horizontal reference plane, and the first horizontal reference plane coincides with the second horizontal reference plane.

[0010] As a preferred technical solution of the present invention, in the same electroplating tank, the anode mechanism includes at least a pair of parallel anode plates, and an independent electroplating channel is formed between each pair of anode plates. The submersible roller is located at the output end of the electroplating channel, and the composite copper film passes through the electroplating channel and around the submersible roller to enter the adjacent conductive mechanism.

[0011] As a preferred technical solution of the present invention, the first pressure roller and the second pressure roller are rubber rollers.

[0012] As a preferred technical solution of the present invention, the lengths of the first conductive roller, the second conductive roller, the first pressure roller, and the second pressure roller are all greater than the width of the composite copper film.

[0013] In summary, compared with the prior art, the beneficial effects of the present invention are: This invention achieves "solution-free linear-surface sealed contact" by setting up a clamping area composed of a first pressure roller, a second pressure roller, a first conductive roller, and a second conductive roller. The high pressure applied by the elastic pressure rollers mechanically forms a triple seal, reducing the liquid film thickness in the clamping area to below the molecular scale. The tangential horizontal entry method guided by the tension mechanism controls the contact angle between the composite copper film and the conductive rollers to a small range, geometrically eliminating the space for plating solution penetration and retention. This establishes a stable metal contact interface between the composite copper film and the conductive rollers with extremely low resistance and a potential difference approaching zero, fundamentally eliminating the possibility of plating solution acting as an ionic conductive medium in the contact area. On the one hand, it completely eliminates the "reverse plating" phenomenon caused by the reduction and precipitation of copper ions on the conductive roller surface due to the presence of plating solution at the interface, ensuring the long-term stability of the equipment and the quality of the plating layer. On the other hand, the extremely low contact resistance provides an efficient and stable current transmission path for the composite copper film, supporting higher electroplating current densities, thereby significantly improving electroplating efficiency and production capacity while ensuring quality. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the device for preventing reverse plating of conductive rollers and long copper rollers according to the present invention. Figure 2 This is a schematic diagram of the second conductive roller of the present invention; Figure 3 A schematic diagram of a traditional PET composite copper film V-shaped electroplating device; Figure 4 This is a schematic diagram of the film and conductive roller at the corner of a traditional PET composite copper film V-shaped electroplating device. Figure 5 A schematic diagram of the conductive roller reverse plating of long copper in a traditional PET composite copper film V-shaped electroplating device; Among them, 1-composite copper film, 11-A side, 12-B side, 2-electroplating tank, 21-anode mechanism, 211-anode plate, 212-electroplating channel, 22-underwater roller, 3-conductive mechanism, 31-first conductive roller, 32-second conductive roller, 33-first pressure roller, 34-second pressure roller, 35-second clamping area, 4-tension mechanism, 41-tension roller, 42-passing roller. Detailed Implementation

[0015] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for illustration and explanation only and are not intended to limit the present invention.

[0016] like Figures 1 to 2 As shown, an embodiment of the present invention provides a device for preventing reverse plating of conductive rollers and long copper rollers, which includes a plurality of electroplating tanks 2 arranged sequentially along the travel path of the composite copper film 1. The electroplating tanks 2 are used to hold plating solution. The electroplating tanks 2 are provided with an anode mechanism 21 that is uniformly immersed in the plating solution and an underwater roller 22 for guiding the composite copper film 1. In this embodiment, there are two electroplating tanks 2. It can be understood that the number of electroplating tanks 2 can be set according to the actual situation. A conductive mechanism 3 is provided between adjacent electroplating tanks 2. The conductive mechanism 3 includes a rotatable first conductive roller 31, a second conductive roller 32, a first pressure roller 33, and a second pressure roller 34. The first pressure roller 33 is arranged opposite to the first conductive roller 31, and the second pressure roller 34 is arranged opposite to the second conductive roller 32, so as to form a first clamping area and a second clamping area 35 respectively when the composite copper film 1 passes through. The composite copper film 1 has an A-side 11 and a B-side 12 facing away from each other, and passes through the first clamping area and the second clamping area 35 in sequence. The roller surfaces of the first conductive roller 31 and the second pressure roller 34 are in contact with the A-side 11 of the composite copper film 1, and the roller surfaces of the second conductive roller 32 and the first pressure roller 33 are in contact with the B-side 12 of the composite copper film 1. The pressure rollers 33 and 34 apply positive pressure to the first conductive roller 31 and the second conductive roller 32 respectively, so that the composite copper film 1 forms a liquid-free linear-surface sealed contact with the first conductive roller 31 and the second conductive roller 32 in the first clamping area and the second clamping area 35 respectively; wherein the anode mechanism 21 is connected to the positive terminal of the power supply, and the first conductive roller 31 and the second conductive roller 32 are connected to the negative terminal of the power supply. The first conductive roller 31 is used to transmit the negative current to the A-side 11 of the composite copper film 1 and to transport the composite copper film 1 so as to make the A-side 11 of the composite copper film 1 conductive. The second conductive roller 32 is used to transmit the negative current to the B-side 12 of the composite copper film 1 and to transport the composite copper film 1 so as to make the B-side 12 of the composite copper film 1 conductive.

[0017] The key to this invention is that the contact angle between the first conductive roller 31, the second conductive roller 32 and the composite copper film 1 is formed entirely by the squeezing action of the first pressure roller 33 and the second pressure roller 34. This structure ensures that there is almost no plating solution residue in the contact angle area, establishing a dry line-to-surface contact between the metals. Under the positive pressure of the first pressure roller 33 and the second pressure roller 34, a tight contact interface similar to a wire connection is formed between the composite copper film 1 and the conductive roller. The contact resistance is extremely low, and the interface potential difference approaches zero. This completely eliminates the conditions for reverse plating induced by plating solution retention from both physical and electrical perspectives.

[0018] The first pressure roller 33 and the second pressure roller 34 apply adjustable positive pressure to the first conductive roller 31 and the second conductive roller 32, respectively. The positive pressure is measured by a line pressure gauge and ranges from 80 to 150 N / mm. This pressure value makes the composite copper film 1 and the conductive roller form a conductive state with a contact resistance of less than 0.5 milliohms in the clamping area, and completely displaces the plating solution between the contact interfaces, forming a stable dry-sealed contact area.

[0019] In this embodiment, a tension mechanism 4 is also provided between two adjacent electroplating tanks 2. The tension mechanism 4 is located on the upstream side of the conductive mechanism 3 along the traveling direction of the composite copper film 1, and is used to guide the composite copper film 1 entering the conductive mechanism 3 so that the composite copper film 1 enters the first clamping area and the second clamping area 35 in a tangential manner.

[0020] Furthermore, the tension mechanism 4 includes a rotatable tension roller 41 and a guide roller 42. The tension roller 41 is located near the output end of the previous electroplating tank 2 and is used to change the direction of the composite copper film 1 and provide tension. The guide roller 42 is located near the input end of the next electroplating tank 2.

[0021] Furthermore, the conductive mechanism 3 and the tension mechanism 4 are both located above the electroplating tank 2. The highest generatrix of the tension roller 41 and the highest generatrix of the through roller 42 are located on the first horizontal reference plane, and the lowest generatrix of the first conductive roller 31 and the highest generatrix of the second conductive roller 32 are located on the second horizontal reference plane. The first horizontal reference plane coincides with the second horizontal reference plane.

[0022] By setting the tension mechanism 4, the present invention allows the composite copper film 1 to enter the clamping area in a horizontal posture in a tangential manner, controlling the wrap angle between the composite copper film 1 and the conductive roller to a small angle. Compared with the large wrap angle of more than 100° in the traditional structure, the contact arc length is greatly shortened. This geometric constraint means that the plating solution has neither enough space to form a continuous liquid film nor enough time to maintain the ion conduction channel in the clamping area. Under the combined action of the elastic sealing effect of the first pressure roller 33 and the second pressure roller 34 and the geometric constraint effect, a "line-surface sealed contact" is formed between the composite copper film 1 and the conductive roller - that is, a solid direct contact area that is linearly distributed along the roller axis and has a narrow band surface contact in the tangential direction, realizing a truly "plating solution-free" environment.

[0023] Furthermore, within the same electroplating tank 2, the anode mechanism 21 includes at least one pair of parallel anode plates 211, with each pair of anode plates 211 forming an independent electroplating channel 212. A submersible roller 22 is located at the output end of the electroplating channel 212, and the composite copper film 1 passes through the electroplating channel 212 and around the submersible roller 22 before entering the adjacent conductive mechanism 3. In this embodiment, the anode mechanism 21 includes two pairs of parallel anode plates 211, located at the input and output ends of the submersible roller 22, respectively.

[0024] Furthermore, the first pressure roller 33 and the second pressure roller 34 are rubber rollers.

[0025] The first pressure roller 33 and the second pressure roller 34 are made of elastic materials, such as polyurethane, silicone rubber, or nitrile rubber. Under positive pressure, they undergo elastic deformation to form a linear sealed contact area with the composite copper film 1, blocking the plating solution outside the first clamping area and the second clamping area 35. This elastic deformation produces a triple sealing effect: First, at the front end of the clamping area, the high-pressure area mechanically scrapes the liquid film, "pushing" the residual plating solution carried out of the composite copper film 1 from the plating solution out of the clamping area; Second, the elastic deformation of the first pressure roller 33 and the second pressure roller 34 fills the microscopic unevenness of the surface of the composite copper film 1 and the conductive roller, blocking the microscopic channels for liquid penetration; Finally, the convergence-divergence gap formed between the pressure roller and the conductive roller generates a dynamic pressure effect, forming a high-pressure repulsive liquid film in the inlet area of ​​the clamping area and a negative pressure suction of residual liquid in the outlet area, so that the thickness of the liquid film in the clamping area is reduced to below 0.1 μm, entering the molecular contact scale. Meanwhile, since the lengths of the first pressure roller 33 and the second pressure roller 34 are both greater than the width of the composite copper film 1, complete coverage of the film edge area is achieved in the axial direction, preventing the plating solution from leaking from the edge.

[0026] Furthermore, the lengths of the first conductive roller 31, the second conductive roller 32, the first pressure roller 33, and the second pressure roller 34 are all greater than the width of the composite copper film 1.

[0027] With the above structure, in practical application, the composite copper film 1 sequentially passes through the highest generatrix of the roller 42 on the left side of the previous electroplating tank 2, the electroplating channel 212 formed between the first pair of anode plates 211 in the previous electroplating tank 2, the liquid roller 22, and the electroplating channel 212 formed between the second pair of anode plates 211 in the previous electroplating tank 2. It then exits the previous electroplating tank 2, is guided by the tension roller 41 on the right side of the previous electroplating tank 2, and sequentially passes through the lowest generatrix of the first conductive roller 31 and the highest generatrix of the second conductive roller 32 along a horizontal tangential path before entering the next electroplating tank 2. Repeat the above process; thus, the first conductive roller 31 can conduct electricity to the A side 11 of the composite copper film 1, and the second conductive roller 32 can conduct electricity to the B side 12 of the composite copper film 1. In this way, the A side 11 and B side 12 of the composite copper film 1 serve as electroplating cathodes, and the anode plate 211 of the previous electroplating tank 2 and the anode plate 211 of the next electroplating tank 2 serve as electroplating anodes. In this way, copper ions in the plating solution in the electroplating tank 2 can accumulate on the A side 11 and B side 12 of the composite copper film 1, thereby achieving the plating of a metallic copper layer on the A side 11 and B side 12 of the composite copper film 1, realizing efficient and continuous double-sided electroplating.

[0028] The working principle of this invention is as follows: The first pressure roller 33 and the second pressure roller 34, made of elastic material, apply positive pressure to the first conductive roller 31 and the second conductive roller 32, respectively, causing the first pressure roller 33 and the second pressure roller 34 to undergo elastic deformation, forming a high-pressure sealing band in the clamping area. Through the triple action of mechanical scraping, micro-gap filling and dynamic pressure suction, the residual plating solution brought out of the plating solution by the composite copper film 1 is blocked outside the clamping area. At the same time, the tension mechanism 4 causes the composite copper film 1 to enter the clamping area in a tangential horizontal manner, controlling the wrap angle between the composite copper film 1 and the conductive roller to a small range, eliminating the space for plating solution penetration and retention in the traditional large wrap angle structure. Under the above dual action, the composite copper film 1 and the conductive roller form a plating solution-free line-surface sealed contact in the clamping area. A metal-metal contact similar to a direct wire connection is established between the composite copper film 1 and the conductive roller, with extremely low contact resistance and an interface potential difference close to zero, which is far lower than the potential required for copper ion reduction. At this point, even if occasional factors (such as tension fluctuations during acceleration and deceleration) cause a temporary increase in the local potential difference, ionizing the copper on the surface of the composite copper film 1 to form copper ions, these copper ions cannot migrate to the surface of the conductive roller and gain electrons to be reduced to metallic copper due to the lack of an ion-conducting medium provided by the plating bath. Simultaneously, good solid-state contact provides a stable current transmission path for high-current-density electroplating, significantly improving electroplating efficiency and capacity while completely eliminating reverse plating on the conductive roller and ensuring continuous production quality.

[0029] It should be understood that the above embodiments are one or more embodiments of the present invention. There are many other embodiments and variations based on the present invention. Any variations and modifications made by those skilled in the art without making pioneering innovations are within the protection scope of the present invention.

Claims

1. A device for preventing reverse plating of conductive rollers with long copper rollers, characterized in that: The system includes multiple electroplating tanks arranged sequentially along the travel path of a composite copper film. Each electroplating tank contains an anode mechanism immersed in a plating solution and an underwater roller for guiding the composite copper film. A conductive mechanism is provided between adjacent electroplating tanks. This conductive mechanism includes a rotatable first conductive roller, a second conductive roller, a first pressure roller, and a second pressure roller. The first pressure roller is positioned opposite to the first conductive roller, and the second pressure roller is positioned opposite to the second conductive roller, forming a first clamping area and a second clamping area respectively as the composite copper film passes through. The composite copper film has opposing A-sides and B-sides and passes sequentially through the first clamping area and the second clamping area. The roller surfaces of the first conductive roller and the second pressure roller contact the A-side of the composite copper film, and the roller surfaces of the second conductive roller and the first pressure roller contact the B-side of the composite copper film. The first pressure roller and the second pressure roller apply positive pressure to the first conductive roller and the second conductive roller respectively, so that the composite copper film forms a liquid-free linear-surface sealed contact with the first conductive roller and the second conductive roller in the first clamping area and the second clamping area, respectively.

2. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 1, characterized in that: A tension mechanism is also provided between two adjacent electroplating tanks. The tension mechanism is located upstream of the conductive mechanism along the direction of travel of the composite copper film and is used to guide the composite copper film entering the conductive mechanism so that the composite copper film enters the first clamping area and the second clamping area tangentially.

3. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 2, characterized in that: The tension mechanism includes a rotatable tension roller and a guide roller. The tension roller is located near the output end of the preceding electroplating tank and is used to change the direction of the composite copper film and provide tension. The guide roller is located near the input end of the following electroplating tank.

4. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 3, characterized in that: The conductive mechanism and the tension mechanism are both located above the electroplating tank. The highest generatrix of the tension roller and the highest generatrix of the roller are located on a first horizontal reference plane, and the lowest generatrix of the first conductive roller and the highest generatrix of the second conductive roller are located on a second horizontal reference plane. The first horizontal reference plane coincides with the second horizontal reference plane.

5. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 1, characterized in that: Within the same electroplating tank, the anode mechanism includes at least one pair of parallel anode plates, with each pair of anode plates forming an independent electroplating channel. The submersible roller is located at the output end of the electroplating channel, and the composite copper film passes through the electroplating channel and around the submersible roller to enter the adjacent conductive mechanism.

6. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 1, characterized in that: The first pressure roller and the second pressure roller are rubber rollers.

7. The device for preventing reverse plating of conductive rollers and long copper rollers according to claim 1, characterized in that: The lengths of the first conductive roller, the second conductive roller, the first pressure roller, and the second pressure roller are all greater than the width of the composite copper film.

Images