JP5751530B2 - Method for electrolytic plating long conductive substrate and method for producing copper clad laminate - Google Patents

Description

  The present invention provides a long conductive substrate in which a long conductive substrate is conveyed using a roll-to-roll method, and repeatedly immersed in an electrolytic plating tank filled with an electrolytic plating solution, and the surface of the long conductive substrate is subjected to electrolytic plating. The present invention relates to a method for electrolytic plating of a conductive substrate. Furthermore, it is related with the manufacturing method of the copper clad laminated board by the electrolytic plating method of a long electroconductive board | substrate.

Electroplating is an industry that includes semiconductor circuit formation, surface treatment of steel strip and copper foil, production of electrolytic copper foil, and production of copper-clad laminates with a copper electrolytic plating film formed on the surface of a resin film such as polyimide. Widely used in the world.
The copper-clad laminate is processed into a flexible wiring board, and is used for COF (Chip on Film) mounting of driver circuits such as liquid crystal displays as well as small electronic devices such as mobile phones.

  By the way, this flexible wiring board is manufactured by using a subtractive method or the like from a three-layer copper-clad laminate in which an adhesive is used between a polyimide film, which is a kind of resin film, and a copper foil. Is done.

  In recent years, as electronic components have become lighter, thinner and shorter, there has been an increasing demand for narrower wiring, so a metal film is formed on the surface of a polyimide film from a conventional three-layer copper-clad laminate without using an adhesive. The transition to a two-layer copper-clad laminate by the metalizing method is ongoing. Such a two-layer copper-clad laminate is not affected by the properties of the adhesive because it has no adhesive, and can achieve a narrow wiring pitch by utilizing the inherent stability of polyimide. Used for COF mounting.

  As a method for obtaining such a two-layer copper-clad laminate, Patent Document 1 discloses that after a metal thin film is laminated on the polyimide film surface by sputtering or vapor deposition, the metal layer is thickened using electroplating or electrolytic plating. A so-called metallizing method is disclosed. Patent Document 2 discloses a method for producing a metal-coated polyimide film using an electrolytic plating apparatus.

On the other hand, regarding the demand for COF, the fine wiring is progressing with the high definition of the liquid crystal display.
Under such circumstances, demands for the appearance quality of the metallized polyimide substrate are becoming stricter. As a requirement for the appearance quality of the metalized polyimide substrate, first, countermeasures against pinholes in the copper plating layer are demanded, and surface defects such as surface irregularities of the copper plating layer of the metallized polyimide substrate are further advanced as the wiring becomes finer. Reduction is required.

  In addition, since the copper-clad laminate is processed by a roll-to-roll method when wiring it to a flexible wiring board, it is used in a long length, so that the roll-to-roll as disclosed in Patent Document 2 is used. Thus, there is a demand for production as a continuous long product.

However, even if a long polyimide film is used as the base material of the copper-clad laminate substrate, the end part is present, and in order to continuously produce the roll-to-roll method, the end part when connecting to the next base material Processing becomes a problem.
That is, the edge processing method for maintaining the quality of the copper-clad laminate is a problem to be solved because it is not disclosed in the surface treatment technology for a long copper foil or the like as well as the technology for manufacturing a copper-clad laminate.

JP 2002-252257 A JP 2009-026990 A

  The present invention relates to a long conductive substrate in which a long conductive substrate is conveyed by a roll-to-roll method and repeatedly immersed in an electrolytic plating tank filled with an electrolytic plating solution, and the surface of the long conductive substrate is subjected to electrolytic plating. To provide an electrolytic plating method for a long conductive substrate by regulating the introduction of the long conductive substrate into the electrolytic plating tank and the processing of the end portion of the long conductive substrate in the electrolytic plating method. is there.

  In order to solve the above-mentioned problems, the present inventors have intensively studied a manufacturing method in order to obtain a substrate having no concavo-convex aggregate in the vicinity of the connection portion when introducing electroplating. The effect of the surface area on the substrate surface was confirmed and the present invention was achieved.

  1st invention of this invention conveys a elongate conductive substrate by a roll-to-roll system, repeats immersion in the electroplating liquid with which the electroplating tank was filled through contact with an electric power feeding roll, The said elongate In the method of electrolytic plating of a long conductive substrate in which electrolytic plating is performed on the surface of the conductive substrate, the long conductive substrate is provided with a long insulating substrate via a connection portion at a tip portion on the transport direction side, Leaded by a long insulating substrate and transported to the electrolytic plating tank, where the connecting portion has a stepped portion formed by overlapping the long conductive substrate and the long insulating substrate, and the long conductive of the connecting portion Covering part using adhesive tape with layer thickness of 40 μm or less provided with adhesive layer on one side of base material, with stepped part formed so that end of long insulating substrate is exposed on power supply roll contact surface side of conductive substrate Of a long conductive substrate, characterized by being coated with A plating method.

  According to a second aspect of the present invention, a long conductive substrate is conveyed by a roll-to-roll method, and repeatedly immersed in an electrolytic plating tank filled with an electrolytic plating solution via a power supply roll, and then on the surface of the long conductive substrate. In the method of electrolytic plating of a long conductive substrate to be subjected to electrolytic plating, the long conductive substrate is provided with a long insulating substrate via a connecting portion at a tip portion on the transport direction side, and the long insulating substrate is led. And is transported to the electrolytic plating tank, and the connecting portion is a connecting portion having a stepped portion formed by overlapping the long conductive substrate and the long insulating substrate, and the end portion of the long conductive substrate of the connecting portion. Is a method for electrolytic plating of a long conductive substrate, wherein the step portion formed by is coated with a coating portion using a pressure-sensitive adhesive tape having a thickness of 40 μm or less provided with an adhesive layer on one side of a substrate.

  The third invention of the present invention is characterized in that the covering portion in the first and second inventions covers a long conductive substrate in a range of 50 mm or more in the direction opposite to the conveying direction from the stepped portion. The method of electrolytic plating of a long conductive substrate.

  According to a fourth aspect of the present invention, the pressure-sensitive adhesive tape forming the covering portion in the first to third aspects is a conductive pressure-sensitive adhesive tape having a metal foil as a base material and a conductive pressure-sensitive adhesive layer laminated. This is an electrolytic plating method for a long conductive substrate.

  According to a fifth aspect of the present invention, there is provided a method for electroplating a long conductive substrate, wherein the metal foil in the first to fourth aspects is a copper foil.

  According to a sixth aspect of the present invention, the long conductive substrate according to the first to fifth aspects includes a thin metal film on the surface of the long resin film without an adhesive. This is an electrolytic plating method for a substrate.

  7th invention of this invention is the electrolytic plating method of the elongate conductive board | substrate characterized by the electrolytic plating solution used for the electroplating in 1st to 6th invention being a copper electrolytic plating solution.

  The eighth invention of the present invention is a method for producing a copper clad laminate comprising a metal thin film without an adhesive on the surface of a long resin film, and a copper coating layer provided on the metal thin film surface, The metal thin film is a laminated film in which a nickel alloy thin film and a copper thin film are provided in this order from the long resin film side, and the copper coating layer is a copper plating layer formed using the electrolytic plating method according to the seventh invention. Is a method for producing a copper clad laminate.

According to the electrolytic plating method for a long conductive substrate of the present invention, it is possible to obtain an electrolytic plating film having no unevenness of 2 μm or more in height or depth on the surface of the electrolytic plating near the connection portion.
Furthermore, when the electroplating method for a long conductive substrate of the present invention is used in a method for producing a copper-clad laminated substrate by a metalizing method, the surface of the copper electroplated film is smooth and suitable for fine wire wiring. A copper-clad laminate can be obtained.

It is a schematic diagram which shows an example of the electroplating apparatus of the roll-to-roll system for enforcing the electroplating method of this invention. FIG. 5 is a schematic cross-sectional view showing a connection portion between a long conductive substrate and a long insulating substrate, where (a) shows a case where the long insulating substrate overlaps the power supply roll contact surface side of the long conductive substrate; (b) is a figure which shows the case where a long insulating board | substrate has overlapped on the base-material side surface of a long conductive board | substrate. It is sectional drawing of the copper clad laminated board by the manufacturing method of this invention.

In general, when carrying out electrolytic plating by conveying a long conductive substrate by a roll-to-roll method, an electrolytic plating apparatus as shown in FIG. 1 is used.
Hereinafter, using this electrolytic plating apparatus 1, metalizing using a long polyimide film with a metal thin film in which a metal thin film is formed on a surface of a long polyimide film on a long conductive substrate by a sputtering method without using an adhesive. The method for electrolytic plating of a long conductive substrate according to the present invention will be described with reference to a method for producing a copper-clad laminate by the method.

[Electrolytic plating equipment]
As shown in FIG. 1, a roll-to-roll electrolytic plating apparatus 1 for carrying out the method of the present invention comprises a plating tank 11, an unwinding roll 12, a transporting guide roll 13, an insoluble anode (hereinafter, described) 14a to 14h), winding roll 15, and power supply rolls 16a to 16e. Note that F is a long polyimide film with a metal thin film (long conductive substrate), and S is a copper-coated long polyimide film (copper-clad laminate).

Here, the anodes 14a, 14b, 14c, 14d, 14e, 14f, 14g, and 14h constitute an electrically independent electrolytic plating cell. Therefore, the surface of the metal film (for example, the conductive layer in the long conductive substrate) of the long polyimide film F with the metal thin film comes into contact with the power supply rolls 16a, 16b, 16c, 16d, and 16e, so that the anodes 14a and 14b respectively. , 14c, 14d, 14e, 14f, 14g, and 14h, a potential difference is generated and electrolytic plating is performed.
Each anode may be a soluble anode or an insoluble anode.

  In the production of a copper-clad laminate, copper electroplating is performed to form a copper coating layer. Therefore, a copper plate that dissolves and becomes a source of copper ions can be used if it is a soluble anode. Also, if an insoluble anode is used, a metal anode such as platinum or lead, or a ceramic anode obtained by coating a titanium frame with a conductive ceramic such as iridium oxide, rhodium oxide, or ruthenium oxide. A copper ion supply source may be provided outside the electrolytic plating tank.

The anodes 14a, 14b, 14c, 14d, 14e, 14f, 14g, and 14h are connected to positive electrodes of control power sources (also referred to as rectifiers, not shown) that are electrically independent of each other. The negative electrode of this control power source is connected to the power supply rolls 16a, 16b, 16c, 16d, and 16e.
That is, the anode 14a constitutes an electrolytic plating circuit by the control power source connected to the anode 14a, the power supply roll 16a, and the long polyimide film F with a metal thin film. Similarly, the anodes 14b, 14c, 14d, 14e, 14f, 14g, and 14h constitute an electrolytic plating circuit.

  Furthermore, the anodes 14a, 14b, 14c, 14d, 14e, 14f, 14g, and 14h are controlled in current density by a control power source connected to each anode so that the current density increases stepwise from the unwinding roll 12 side. Has been made. The control for increasing the current density in stages is appropriately determined in consideration of the film thickness of the copper plating film layer.

  Moreover, the electroplating apparatus 1 includes various known apparatuses used for transporting a long polyimide (resin) film such as a control roll for controlling the tension of the long polyimide film F with a metal thin film, and stirring and supplying of a plating solution. Various known devices can also be added.

The plating tank 11 is filled with an acidic plating solution mainly composed of sulfuric acid and copper sulfate.
The long polyimide film F with a metal thin film is unwound and conveyed from the unwinding roll 12 with the width direction being substantially horizontal, and the conveying direction can be changed so as to be immersed in the plating solution of the plating tank 11 by the power supply roll 16a. The conveyance direction is changed to the plating liquid surface direction of the plating tank 11 by being reversed by the conveyance guide roll 13 in the plating tank 11. Further, the adjacent power feed roll 16b, transport guide roll 13, power feed roll 16c, transport guide roll 13, power feed roll 16d, transport guide roll 13, and power feed roll 16e are transported in this order to immerse in the plating solution. Repeated.
Finally, the copper-coated long polyimide film S (in this state, since the electroplating is completed, it becomes a copper-clad laminate) is taken up by the take-up roll 15.

  The electrolytic plating apparatus 1 is of a type in which a long polyimide film F with a metal thin film is vertically immersed in a plating solution, but the direction when the long polyimide film F with a metal thin film is immersed is limited to a vertical direction. Instead, it may be immersed obliquely in the plating solution in the plating tank 11, and the direction in which the long polyimide film with metal thin film (long conductive substrate) F is immersed in the plating tank 11 can be selected as appropriate.

  However, when electrolytic plating is carried out using the electroplating apparatus 1 shown in FIG. 1 while conveying a long conductive substrate (long polyimide film F with a metal foil film in FIG. 1), the following problems occur. It was happening.

[Conveyance of long conductive substrates and problems]
The long conductive substrate is transported through the electrolytic plating apparatus 1 to form a copper plating film layer having a desired film thickness on the surface of the copper thin film layer. It is necessary to perform electroplating on all the anodes provided in 1.
Usually, before the operation of the electroplating apparatus 1, when a long conductive substrate is set in advance on the transfer path and the operation is started, the anode 14 a (the most upstream in the transfer path (incoming side: unwinding roll 12) is set. The long conductive substrate placed downstream of the anode on the side) cannot be plated with copper at the desired film thickness, resulting in product loss and a loss in yield and economy. Occurs.

What is more problematic than this problem is the discoloration of the copper electrolytic plating layer, the seizure defect between the power supply roll and the like and the long conductive substrate.
Usually, the film thickness of the conductive layer of the long conductive substrate used (copper thin film layer of the long polyimide film with metal thin film) is 50 nm to 1000 nm, and the resistance value per unit area is 10 ⁻¹ Ω.
Since the electroplating apparatus 1 is controlled by each anode and each power supply roll so that the current increases as it progresses downstream (the carry-out side: the take-up roll 15 side), the long electroconductive substrate is preliminarily placed on the electroplating apparatus. When the operation is started with 1 and depending on the position of the feeding roll, a large excess current flows in the copper thin film layer, which may cause discoloration of the copper electrolytic plating layer. This would cause a burn-in defect between the roll or the like and the long conductive substrate.

Therefore, in order to prevent these problems, a long insulating substrate (so-called dummy substrate) such as a PET film is connected to the tip of the substrate when the long conductive substrate is carried into the electroplating apparatus 1, Electrolytic plating is started by setting so that the long conductive substrate is placed at a position not in contact with the power supply roll 16a.
In such an arrangement, the long conductive substrate is guided by the long insulating substrate and conveyed in the electroplating apparatus 1, so that electrolytic plating in a steady state can be performed from the first power supply roll 16 a, and the copper is gradually added. The film thickness of the plating layer is increased, so that a large excess current is not applied, and these problems do not occur.

The connection part of a long conductive substrate such as a long polyimide film with a metal thin film and a long insulating substrate such as a PET film has a configuration shown in the schematic cross-sectional view of FIG.
FIGS. 2A and 2B are different from each other in how the long conductive substrate and the long insulating substrate are superposed, and FIG. 2A shows the long insulating property on the power supply roll contact surface side of the long conductive substrate. The case where the board | substrate has overlapped is shown, (b) shows the case where the long insulating board | substrate has overlapped with the base material side surface of the long electroconductive board | substrate.

In the connecting portion 20, an end portion 21 of a long conductive substrate (long polyimide film F with a metal thin film) and an end portion 22 of a long insulating substrate (PET film) overlap to form step portions 23a and 23b. The step portions 23a and 23b constituted by the end portions 21 and 22 of the substrate are covered with adhesive tapes 24A and 24B.
In the connection part 20, the long electroconductive board | substrate (long polyimide film F with a metal thin film) and the long insulating board | substrate (PET film) may be bonded together with the double-sided adhesive tape 25 (refer Fig.2 (a)). If the mechanical strength of the connecting portion can be maintained as shown in FIG. 2B, the double-sided adhesive tape is not necessary.

An adhesive layer and a metal foil (for example, a copper foil) were laminated on the adhesive tape 24A that adheres to the conductive layer (copper thin film layer of the long polyimide film F with a metal thin film) surface of the long conductive substrate in contact with the power supply roll. It is desirable to cover the stepped portions 23a and 23b of the connecting portion 20 formed by the long conductive substrate and the long insulating substrate using an adhesive tape.
In particular, since the conductive layer (copper thin film layer) is in contact with the power supply roll and is energized, the use of a conductive adhesive tape for the connecting portion 20 can be expected to have an effect of further stabilizing the energization and suppressing abnormal discharge.

A plurality of steps are formed on both surfaces of the connecting portion 20 by a long conductive substrate (long polyimide film F with a metal thin film), a long insulating substrate, an adhesive tape, etc., but the conductive surface is a surface in contact with the power supply roll. It is desirable that the step h with respect to the layer surface (the surface of the copper thin film layer) does not exceed 100 μm.
Steps that are substantially perpendicular to the surface of the conductive layer (copper thin film layer) and have a difference exceeding 100 μm may cause abnormal discharge in the power supply roll, and discoloration of the surface of the electrolytic copper plating layer may occur. In addition, when the step exceeds 100 μm, it may be transferred to the copper-clad laminate that has been scraped off, and the copper-clad laminate may be deformed. On the other hand, since no current flows on the resin base (polyimide) side on the back side, there is no fear of abnormal discharge due to a step.

  Furthermore, the portion where the concavities and convexities of 2 μm or more gather at the depth or height is generated on the surface of the copper plating layer formed by defining the connection portion and carrying and electrolytic plating as described above. There is a case.

The interval between the uneven portions is generated at the interval between the feeding rolls. When the uneven portion is observed, the uneven portion is generated in the transport direction of the connecting portion. It occurs immediately after this, and since this aggregate is generated in the power supply roll cycle, it is considered that the dirt on the power supply roll has been transferred.
That is, since the substrate is energized at the moment when the connecting portion comes into contact with the power supply roll, the connecting portion is at a positive potential with respect to the power supply roll to be contacted. Therefore, it is considered that the copper thin film of the long conductive substrate is melted and contaminates the power supply roll.

  Therefore, in the present invention, the step portion of the surface on the conductive layer (copper thin film layer) side of the long conductive substrate, that is, the surface in contact with the feeding roll is covered with an adhesive tape having a layer thickness of 40 μm or less. By reducing the level difference h of the pressure-sensitive adhesive tape at the level difference part, it is possible to suppress dissolution due to polarization.

Further, the length (L) of 50 mm or more from the stepped portions 23a and 23b toward the direction opposite to the conveying direction on the surface on the conductive layer (copper thin film layer) side of the long conductive substrate, that is, the surface in contact with the feeding roll The covering portion 26 is provided.
As the covering portion 26, the adhesive tape used for covering the step portion (23b in FIG. 2A, 23a in FIG. 2B) may be used continuously, or may be covered separately. As described above, in the connection portion, the conductive layer (copper thin film layer) of the long conductive substrate is reversely transferred from the step portion 23b formed by the long insulating substrate or the step portion 23a formed by the long conductive substrate. A range having a length of 50 mm or more (in the direction indicated by the white arrow in FIG. 2) is covered with the covering portion, and the step formed by the adhesive tape 24A covering the step portions 23a and 23b is made gentle, It is possible to alleviate the dissolution of copper in the thin film layer. In addition, although the length of a coating | coated part needs 50 mm or more in order to acquire the said effect, it is good to determine timely also considering the loss amount of the electroplating layer at the time of electroplating.

  Further, when a conductive material (for example, conductive adhesive tape) is used for the stepped portion coating or the covering portion, the long conductive substrate can be coated with the stepped portion as the thickness of the copper plating layer increases by electrolytic plating. Electrolytic plating is also applied to the surface of the covering portion, so that the thickness increases and the step is gradually relaxed. As a result, the level difference becomes gentle and the dissolution of copper when contacting the power supply roll is also suppressed, which is more preferable.

Such a connection portion is not only provided at the front end of the long conductive substrate shown in FIG. 2 but also when connecting long conductive substrates to handle a longer long conductive substrate. Moreover, a favorable electroplating layer can be brought about by utilizing for the connection part of the elongate conductive substrates.
It should be noted that the start of energization of each power supply roll may be performed when the long conductive substrate begins to be immersed in the electrolytic plating solution immediately after the connection portion passes through the power supply roll. That is, it is only necessary to start energization with the anode from when the long conductive substrate starts to be immersed facing the anode. Naturally, the energization may be terminated if the end of the long conductive substrate passes through the opposite anode.

The long insulating substrate used in the present invention is exemplified by a PET film, but the material is not limited to the PET film, and can be transported by a roll-to-roll method and cut even when immersed in a plating solution. The film may have a mechanical strength that does not occur, and is appropriately selected from polyester films such as PET, polyimide films, polyamide films, polytetrafluoroethylene films, polyphenylene sulfide films, and other resin films. Of these, PET films are commercially inexpensive and easily available.
Further, the thickness of the long insulating substrate may be a thickness having the flexibility of the long conductive substrate and the roll-to-roll method, and is 0.3 to 5 times the thickness of the long conductive substrate. The range can be selected as appropriate.

  The pressure-sensitive adhesive tape and covering portion that covers the stepped portion are layers in which a pressure-sensitive adhesive layer is laminated on the surface of a metal substrate, and conductive properties such as carbon are kneaded into the pressure-sensitive adhesive that constitutes the pressure-sensitive adhesive layer. A conductive pressure-sensitive adhesive tape having a conductive pressure-sensitive adhesive layer is desirable from the viewpoint of realizing the effect, ease of handling, and work efficiency.

  The long conductive substrate used for the electrolytic plating method in the present invention is not limited to a long polyimide film with a metal thin film or a copper clad laminate, and the same applies to a long metal foil or a metal strip. . In the case of electrolytic plating of a substrate in which the entire substrate, as well as the front and back surfaces, as well as metal foil, is electroplated according to the method of electroplating a long conductive substrate of the present invention on the surface in contact with the power supply roll, the connecting portion is connected with a conductive adhesive tape May be formed.

  Next, the metalizing including the electrolytic plating method of the present invention using a long polyimide film with a metal thin film in which a metal thin film is formed on the surface of the long polyimide film by a sputtering method without using an adhesive for a long conductive substrate. A method for producing a copper clad laminate by the method will be described.

[Copper laminate]
FIG. 3 shows a cross-sectional view of a copper-clad laminate according to the present invention.
The surface of the polyimide film 2 is configured by laminating a base metal layer 3 such as a nickel-chromium alloy, a copper thin film layer 4 and a copper plating film layer 5 in this order. A laminated body of the base metal layer 3 and the copper thin film layer 4 is referred to as a metal thin film layer 6. Further, the copper plating film layer 5 may be formed in combination with an electrolytic plating method or an electroless plating method.

  In the method for producing a copper clad laminate according to the present invention, first, a base metal layer 3 such as nickel, a nickel-based alloy or chromium is formed on the surface of the polyimide film 2 by a sputtering method. The thickness of the base metal layer 3 is not particularly limited, but is generally 5 to 50 nm. Known nickel alloys such as nickel-chromium alloy, nickel-chromium-molybdenum alloy, nickel-vanadium-molybdenum alloy can be used as the nickel-based alloy that can be used for the base metal layer. However, the metal used for the base metal layer needs to pay attention to the insulating property of the flexible wiring board and the etching property by the subtractive method.

Subsequently, in order to give good conductivity to the surface of the base metal layer 3, a copper thin film layer 4 is provided by using a sputtering method of a dry plating method, and a long conductive substrate (long polyimide film with a metal thin film) is provided. Form.
The thickness of the copper thin film layer 4 formed by this process is 50 to 1000 nm, and is generally 50 nm to 500 nm in terms of productivity.

Further, a copper layer made of a copper plating film layer 5 is provided on the surface of the metal thin film layer 6 made of a laminate of the base metal layer 3 and the copper thin film layer 4, that is, the surface of the copper thin film layer 4.
The copper layer formed of the copper plating film layer 5 has a desired film thickness by an electrolytic plating method that is a kind of wet plating method or a combination of an electroless plating method and an electrolytic plating method that are a kind of wet plating method.
By using the electrolytic plating method according to the present invention for the electrolytic plating method used to form the copper plating film layer 5, it is possible to obtain a long copper-clad laminate having excellent surface properties.

The film thickness of the copper plating film layer 5 formed on the surface of the metal thin film layer is generally 5 to 18 μm, for example, when a circuit pattern is formed by a subtractive method.
In addition, when forming the copper plating film layer 5 by using both the electroless plating method and the electrolytic plating method, copper is formed on the surface of the metal thin film layer 6 by electroless plating, and then by the electroless plating. Electrolytic plating is performed on the film formation surface.

A long polyimide film with a width of 50 cm, “Kapton (registered trademark) 150EN (thickness: 38 μm) manufactured by Toray DuPont Co., Ltd.”, and a vacuum degree of 0.01 to 0.1 Pa in this polyimide film. Heat treatment was performed at 150 ° C. for 1 minute.
Subsequently, a base metal layer containing 20% by weight of chromium is formed on the polyimide film by sputtering to a thickness of 20 nm, and a copper thin film layer is formed to a thickness of 100 nm to form a long polyimide film F with a metal thin film (long conductive substrate). )
A roll-to-roll type sputtering apparatus was used for sputtering.

  After sputtering, a copper layer having a thickness of 8 μm was formed by electrolytic plating using the electrolytic plating apparatus 1 of FIG. The basic composition of this plating solution is a copper sulfate solution having a pH of 1 or less, and a predetermined amount of an organic additive was added thereto for the purpose of ensuring the smoothness of the copper plating film. The current density of each anode was as shown in Table 1.

As shown in FIG. 2A, step portions 23a and 23b are formed so that the end portion 21 of the long polyimide film F with a metal thin film and the long PET film (long insulating substrate) 22 having a thickness of 50 μm overlap each other. Using a 35 μm thick copper adhesive tape with a conductive adhesive layer laminated to the copper foil of the base material on the copper thin film layer side so as to cover the step portion, the long polyimide film with metal thin film from the step portion The copper thin film layer surface of F was affixed to cover 72 mm (L), and the back surface was affixed to the PET film surface by 15 mm from the stepped portion with an insulating adhesive tape having a layer thickness of 50 μm.
The long polyimide film with a metal thin film provided with the PET film at the tip was guided to the electroplating apparatus 1 and conveyed, and a current was passed through the power supply roll to produce a copper clad laminate.
In the vicinity of the connection portion of the obtained substrate, there were no aggregates of irregularities when observed with an optical stereomicroscope, and a good result of clearing the appearance inspection was obtained.

  A copper-clad laminate was produced in the same manner as in Example 1 except that an insulating tape having a layer thickness of 18 μm obtained by laminating an insulating adhesive layer on an insulating base material was attached to the metal surface at the top of the substrate. In the vicinity of the connection portion of the obtained copper-clad laminate, there was no aggregate of irregularities, and good results were obtained that cleared the visual inspection visually.

  A copper clad laminate was produced in the same manner as in Example 2 except that an insulating adhesive tape was applied so as to cover the copper thin film layer surface of the long polyimide film F with a metal thin film 82 mm from the stepped portion. In the vicinity of the connection portion of the obtained copper-clad laminate, there was no aggregate of irregularities, and good results were obtained that cleared the visual inspection visually.

(Comparative Example 1)
A copper clad laminate was produced in the same manner as in Example 1 except that a copper adhesive tape having a layer thickness of 50 μm was used as the conductive adhesive tape. In the vicinity of the connection part of the obtained copper-clad laminate, an aggregate of irregularities was observed, and the appearance inspection could not be cleared.

(Comparative Example 2)
A copper-clad laminate was manufactured in the same manner as in Comparative Example 1 except that a copper adhesive tape was used as the conductive adhesive tape and the copper thin film layer surface of the long polyimide film F with a metal thin film was covered by 28 mm (L). In the vicinity of the connection part of the obtained copper-clad laminate, an aggregate of irregularities was observed, and the appearance inspection could not be cleared.

DESCRIPTION OF SYMBOLS 1 Electrolytic plating apparatus 2 Polyimide film 3 Underlying metal layer 4 Copper thin film layer 5 Copper plating film layer 6 Metal thin film layer 11 Plating tank 12 Unwinding roll 13 Conveyance rolls 14a-14h (insoluble) Anode 15 Winding roll 16a -16e Feed roll 20 Connection portion 21 End portion 22 of long conductive substrate (long polyimide film with metal thin film) End portion 23a of long insulating substrate (PET film) Step portion 23b formed by the long conductive substrate Step part 24A formed by the long insulating substrate Covering part 24B covering the power supply roll contact surface side Covering part 25B covering the opposite side of the power supply roll contact surface Double-sided adhesive tape 26 The power supply roll contact surface side of the long conductive substrate Covering portion L Covering length 26 [mm]
F Long polyimide film with metal thin film (long conductive substrate)
S Copper-coated long polyimide film (copper-clad laminate)
h Step height [μm] with the conductive layer surface of the long conductive substrate

Claims (8)

The long conductive substrate is transported by a roll-to-roll method, is repeatedly immersed in an electrolytic plating solution filled in an electrolytic plating tank through contact with a power supply roll, and electroplating is performed on the surface of the long conductive substrate. In the electrolytic plating method of the long conductive substrate to be applied,
The long conductive substrate is provided with a long insulating substrate via a connecting portion at a tip portion on the transport direction side, and is transported to the electrolytic plating tank by the long insulating substrate leading,
The connecting portion is a connecting portion having a step portion formed by overlapping the long conductive substrate and the long insulating substrate,
A step portion formed so that an end portion of the long insulating substrate is exposed on the side of the power supply roll contact surface of the long conductive substrate of the connecting portion, and a layer thickness of 40 μm or less provided with an adhesive layer on one surface of the base material. An electroplating method for a long conductive substrate, characterized in that it is covered with a covering portion using an adhesive tape. A long conductive substrate is conveyed by a roll-to-roll method, repeatedly immersed in an electrolytic plating tank filled with an electrolytic plating solution via a power supply roll, and subjected to electrolytic plating on the surface of the long conductive substrate. In the electroplating method of the conductive substrate,
The long conductive substrate is provided with a long insulating substrate via a connecting portion at a tip portion on the transport direction side, and is transported to the electrolytic plating tank by the long insulating substrate leading,
The connecting portion is a connecting portion having a step portion formed by overlapping the long conductive substrate and the long insulating substrate,
The step portion formed by the end portion of the long conductive substrate of the connection portion is covered with a covering portion using an adhesive tape having a layer thickness of 40 μm or less provided with an adhesive layer on one side of the base material. Electrolytic plating method for conductive substrate.   3. The long conductive substrate according to claim 1, wherein the covering portion covers the long conductive substrate in a range of 50 mm or more in a direction opposite to the conveying direction from the stepped portion. Electroplating method.   The long adhesive according to any one of claims 1 to 3, wherein the adhesive tape forming the covering portion is a conductive adhesive tape in which a metal foil is used as a base material and a conductive adhesive layer is laminated. Electrolytic plating method for conductive substrate.   The method for electrolytic plating of a long conductive substrate according to any one of claims 1 to 4, wherein the metal foil is a copper foil.   The electrolysis of a long conductive substrate according to any one of claims 1 to 5, wherein the long conductive substrate includes a metal thin film on the surface of the long resin film without using an adhesive. Plating method.   The electrolytic plating method for a long conductive substrate according to any one of claims 1 to 6, wherein the electrolytic plating solution used for the electrolytic plating is a copper electrolytic plating solution. A method for producing a copper clad laminate comprising a metal thin film on the surface of a long resin film without using an adhesive, and a copper coating layer provided on the metal thin film surface,
The metal thin film is a laminated film provided in the order of a nickel alloy thin film and a copper thin film from the long resin film side,
The said copper coating layer is a copper plating layer formed using the electrolytic plating method of Claim 7, The manufacturing method of the copper clad laminated board characterized by the above-mentioned.

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