JPS6056796B2 - Method and device for manufacturing ultra-thin copper foil laminates using high-speed electrolysis method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for producing ultra-thin copper foil laminates by a high-speed electrolysis method using a drum.

Traditionally, copper foil has been manufactured using the drum method, in which a cylindrical drum is used as a cathode, an anode is provided at a corresponding position in an electrolytic solution, copper foil is electrodeposited on the circumferential surface of the rotating drum, and then peeled off. There is a method, but this method is suitable for thicknesses of 5 to 20 μm.
It could not be used for ultra-thin copper foil of m.

Firstly, it is extremely difficult to peel the thin copper foil from the drum surface without causing cuts or wrinkles, and secondly, because it is used for printed circuits, etc.
When roughening at least one side of the copper foil peeled off from the drum to improve adhesion, it is extremely difficult to handle it without causing edges or wrinkles. This is because in subsequent steps such as lamination, punching, and trilling, it will be difficult to handle unless it is protected by a carrier foil of 20 μm to 40 μm thick made of metal such as copper, aluminum, or iron. Therefore, in manufacturing ultra-thin copper foil laminates, a carrier foil made of copper, aluminum, etc. is unwound, and this is used as a cathode. It is electrodeposited onto a foil, then introduced into a secondary electrolytic bath to roughen the surface.
The commonly used method was to wash it with water, apply anti-corrosion treatment, dry it, and then roll it up. Ultra-thin copper foil laminates have been manufactured by applying an adhesive to the rough surface of the thus obtained copper foil using a separate device, or by laminating prepregs made of glass fiber epoxy or the like under pressure. In addition, in the method of manufacturing copper foil laminates using a drum, the copper foil is electrodeposited on the circumferential surface of a cylindrical drum made of lead, lead alloy, stainless steel, titanium, etc., and then wound into a roll and then roughened. The manufacturing process, washing with water, drying process, adhesive coating process, and lamination process were each performed using separate equipment.

Therefore, the present invention, in which a carrier film is laminated and peeled off from a copper foil that has been subjected to various steps of surface roughening, water washing, and drying, could not be adopted in conventional copper foil manufacturing methods. In addition, in the conventional electrolytic manufacturing method of copper foil, even if it is a drum method, there is a limit to the amount of electrolyte that can be circulated, and the gas generated during electrolysis has a negative effect on the electrodeposited surface, so it is difficult to reduce the current density. As a result, the electrolytic process required a lot of time, tending to increase the size of equipment and product costs. The present invention provides a method and apparatus for manufacturing ultra-thin copper foil laminates all at once by employing a drum method that is superior in terms of production efficiency and purity.

Thin copper foil, which cannot be peeled off using the normal drum method, can be reliably peeled off by laminating a carrier film while peeling it off.

Electrodeposition process, surface roughening process, water washing process,
According to the present invention, the drying process is carried out all at once, and the copper foil is peeled off while laminating the carrier film, and the carrier foil is further laminated on the shiny side (the shiny side of the copper foil). It is possible to produce ultra-thin copper foil with agent or ultra-thin copper foil laminate. The present invention provides a rotating drum and an anode plate having a concentric arc-shaped cross section,
The anode plate also has the function of an electrolytic cell. That is, the electrolytic solution is circulated through the gap bath between the negative and positive electrodes at a high speed of 0.3 to 3.0 ml sec, and copper foil is electrodeposited on the rotating cathode drum. Therefore, high-speed circulation and high current density can be obtained. Furthermore, by dividing the rotating cathode surface into multiple zones using an acid-resistant elastic material made of synthetic or natural raw comb, the process of roughening, washing, and drying is completed on the drum surface. An ultra-thin copper foil laminate is manufactured all at once by laminating a carrier film, pressing it, peeling it off, and then pasting the carrier foil on the shiny side.
An embodiment of the present invention will be described in detail below with reference to FIGS. 1 and 2.

FIG. 1 is an explanatory cross-sectional view of an embodiment of the present invention. The drum 1 is made of a material such as stainless steel or titanium, has a polished surface, and serves as a cathode.

The drum surface consists of a main electrolysis zone 1a1, a secondary electrolysis zone 1b1, a washing zone 1C, a drying zone 1d, a peeling zone 1e, and a polishing zone 1f. Reference numeral 2 denotes an anode, which is made of lead, tin, antimony, etc., and is made of a lead alloy or other insoluble material, and is connected to the drum 1 at a voltage of 1 to 10V, preferably 3 to 5w1.
A concentric arc-shaped jacket is formed by maintaining a gap bus 3 of n, and also has the function of an electrolytic cell.

The electrolyte injection groove 4 divides the anode 2 and opens into the gap bus 3, into which an electrolyte injection pump 5 presses the electrolyte. Furthermore, if necessary, a concentration replenishment pipe 6 is provided to penetrate through the anode 2 to replenish the copper concentration consumed by electrolysis. Electrolyte discharge ports 7 are provided at both ends of the anode 2 and communicate with a gas-liquid separation tank 8 .

In the gas-liquid separation tank 8, gas such as oxygen generated by electrolysis is separated from the electrolytic tailing liquid, and the electrolytic tailing liquid is circulated after adjusting its concentration, and the oxygen is oxidized in a metal dissolution tank (not shown). Used for blowing for extraction. A water nozzle 9 communicates with a water supply pipe 10 and washes the surface of the copper foil 11 on the drum surface with water.

12 is a washing tail liquid discharge pipe.

Reference numeral 13 is a forced dryer, in which the hot air sent from the hot air blower 14 is in continuous contact with the copper foil 11 for a certain period of time, and then discharged from the blower 1.
It is discharged from 5.

A thermocompression peeling roll 16 is provided, and the carrier film 21 unwound from the carrier film unwinding machine 17 is laminated on the copper foil 11 on the drum, and is peeled off while being pressed.

In order to strengthen the lamination, the bonding is performed while being reheated using a pair of thermocompression rolls 22. If at least one of the thermocompression rolls 22 is heated to a predetermined temperature, the other roll does not particularly require heating. Carrier foil unwinding machine 2
A carrier foil 25 made of copper, aluminum, iron or other material is unwound from 4 and is laminated to the shiny side of the laminate 23 by a pair of laminating rolls 26. The thus obtained ultra-thin copper foil laminate with carrier foil 27 is wound on a coil winder 28. Reference numeral 18 denotes a rubber blade, and although high-quality candy rubber was used in this embodiment, other natural or synthetic rubbers or synthetic resins may be used as well, but they have the elasticity to allow them to slide in close contact with the drum surface. Stay warm,
There is no problem as long as it is not affected by the electrolyte.

In other words, the drum surface rotated by the rubber blade 18 is
By dividing the zone into the above zones, various substances present near the surface of each zone can be completely separated from each other. The rubber blade 18a has one end in close contact with the gas-liquid separation tank 8a, and the other end in sliding contact with the drum 1, and guides all of the electrolytic tailing liquid discharged from the electrolyte outlet 7 to the gas-liquid separation tank 8a. One end of the rubber blade 18b is in close contact with the gas-liquid separation tank 8b, and the other end is in sliding contact with the copper foil 11 on the drum surface, completely separating the secondary electrolysis zone 1b from the washing zone 1c, and removing electrolytic tailing liquid and generated Prevent oxygen gas etc. from entering the washing zone 1c. The rubber blade 18c separates the washing zone 1c and the drying zone 1d without interfering with the rotation of the drum 1. A polisher 19 is used to polish the drum surface after the copper foil 11 has been peeled off in preparation for the next electrodeposition.

The configuration is as described above, and the effects will be explained below.

Rotate the drum 1 in the direction of the arrow in Fig. 1 and fill the electrolyte injection groove 4a.
An electrolyte is pressurized into the gap bath 3 by an electrolyte injection pump 5. An acidic aqueous solution of copper sulfate, copper borofluoride, etc. was supplied as the electrolyte. The electrolyte flows in the gap bath 3 in the direction of the arrow at a rate of 0.3 to 3.07 TLISe depending on the required thickness and current density.
The electrolyte flows at a flow rate of C, and the solute consumed by electrolysis is replenished via the concentration supply pipe 6 and discharged from the electrolyte discharge port 7. The electrolyte for nodularization is supplied from the electrolyte injection groove 4b, and the concentrated electrolyte is further replenished from the concentration supply pipe 6. On the other hand, as the drum 1 rotates, copper foil is electrodeposited on the drum surface. Go on,
A predetermined thickness is reached at the end of the electrolysis zone 1a. In the secondary electrolytic zone 1b, an electrolytic solution for secondary electrolytic treatment (in this example, the electrolytic solution for nodularization and the same composition as the electrolytic solution for copper electrodeposition was used) is supplied, and the surface roughening progresses. , secondary electrolysis. At the end of zone 1b, the electrolyte is discharged to gas-liquid separation tank 8b. The electrolyte injection groove 4a divides the anode into anodes 2a and 2b, and the electrolyte injection groove 4b divides the anode into 2b and 2c. Therefore, since different voltages can be applied to each anode, electrolysis can be performed at the optimum current density in each zone. In this embodiment, an electrolytic solution having the same composition was used in both the electrodeposition and nodularization steps, but the gap bath 3 can be divided into two parts using a rubber blade to supply different electrolytic solutions. Approximately 1A1cF1 in the main electrolytic zone! Electrolysis was carried out at a current density of , and desirable results were obtained. The gap bath between drum 1 and anode 2 is 3-5
? Good. There is a water washing zone 1c in the ascending zone after the completion of electrolysis.
and a drying zone 1d. The rinsing zone 1c is surrounded by rubber blades 18b and 18c, and the copper foil on the drum surface is sprayed with water by a water spray nozzle 9, and the rinsing liquid is completely separated and discharged without mixing with the electrolytic tailing liquid. A forced dryer 13 is provided in the adjacent drying zone 1Jd,
After washing with water, the copper foil is dried with hot air. The carrier film 21 is preferably made of a material that has flexibility enough to reinforce the thin copper foil, and is coated or laminated on the matte side, that is, the non-glossy side, of the copper foil in the conventional subsequent process of manufacturing a copper foil laminate.

As the carrier foil, conventionally used metal foils such as copper and aluminum are used. Furthermore, according to the present invention, the carrier foil is not required to function as a cathode as in the past, and it is sufficient to simply protect the thin copper foil until the punching or drilling process of printed circuit manufacturing. It does not need to be metal as long as it is made of a material that can be peeled off. In FIG. 2, a sheet-like adhesive film 30 formed on a release paper 29 is used as the carrier film 21, and 2 as the carrier foil 25.
It is a cross-sectional explanatory view of the vicinity of peeling zone 1e when aluminum foil with adhesive of 0 to 40 μm is used.

The carrier film 21 is a carrier film unwinding machine 1.
When the adhesive 30 and the matte side 31 of the copper foil 11 are heated and pressed together as they pass through the lower surface of the thermocompression peeling roll 16, the copper foil 11 is peeled off from the drum 1. Next, when passing between a pair of laminating rolls 26, the carrier foil 25 is crimped and laminated to the shiny side 32 of the copper foil 11 to obtain an ultra-thin copper foil laminate 27, which is wound on a coil winder 28. In the subsequent lamination process, the release paper 29 is peeled off from the adhesive-attached ultra-thin copper foil laminate thus obtained to produce a laminate. In this example, an adhesive film with release paper was used as the carrier film, but polyimide resin, epoxy resin,
Sheets of synthetic resins such as phenol resin and polyester resin, impregnated paper, glass and other materials impregnated,
Alternatively, a surface prepreg film such as one coated with an adhesive can also be used.

If further strengthening of the lamination is required, the bond is strengthened by passing between the thermocompression roll 22b which is in sliding contact with the hot thermocompression roll 22a. One thermocompression roll 22b may or may not be heated depending on the properties of the film. Further, the thermocompression bonding roll 22a and the thermocompression bonding peeling roll 16 can be brought into direct sliding contact to strengthen the lamination. According to the present invention, a copper foil with a thickness of 10 μm that is well nodular and has no pinholes is obtained under the following conditions, and an adhesive film with release paper is laminated and peeled off, and then a carrier foil made of aluminum foil is laminated all at once. A good adhesive-coated ultra-thin copper foil laminate was obtained. Cathode: Stainless steel (SUS-27) drum Anode: Hard lead plate Peripheral speed of drum: 17T 1.1 min Flow rate of electrolyte: 2.0 m. 1sec Plate spacing: 3.2Tfr:Fn Electrolyte: CU88full. ．． H2SO4l4Oyle
l Temperature 60°C Current density: 1AIcIt (electrodeposition process in the main electrolysis zone) 3A1c1i (nodularization process in the secondary electrolysis zone) Electrolysis time: 25sec (electrodeposition process) 2sec (nodularization process) Rice vapor ( Silicone resin for release paper (Shin-Etsu Silicone)
96) was coated or impregnated with a paper phenol-based adhesive by a known method, and heated at 140°C, 5) Ec
It was dried to some extent and made into a film.

As described above, according to the present invention, high current density and high-speed electrolyte circulation can be obtained, and the steps of electrodeposition of copper foil, secondary electrolytic treatment, washing with water, and drying can be performed using the same drum. The steps of coating or laminating the surface prepreg film and laminating the carrier foil can be performed all at once.

Therefore, according to the present invention, it has become possible to manufacture ultra-thin copper foil laminates using a drum method.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of one embodiment of the present invention, and FIG. 2 is an explanatory cross-sectional view of the vicinity of the peeling zone of the drum.

Claims (1)

[Claims] 1. A cylindrical metal drum partially immersed in an electrolytic solution and rotating at a constant speed is used as a cathode, and a copper foil is placed on the drum surface using an anode having an arcuate cross section concentric with the drum. a step of electrodepositing copper foil on the drum surface in a method of electrodepositing
The process of applying secondary electrolytic processing to the surface of the copper foil, and the process of washing and drying the copper foil with water while still attached to the drum surface are performed while the drum rotates once, and when peeled off from the drum surface, a sheet is formed. A carrier film such as an adhesive or a surface prepreg film is laminated and peeled off together with the carrier film, and then pressure bonded with or without heating, and then a carrier foil for ultra-thin copper foil is laminated on the shiny side. A manufacturing method for ultra-thin copper foil laminate products. 2. The method according to claim 1, wherein the copper foil has a thickness of 5 to 15 μm. 3 In an apparatus in which a cylindrical metal drum that rotates at a constant speed while partially immersed in an electrolytic solution is used as a cathode, and an anode having an arcuate cross section concentric with the drum is used to electrodeposit copper foil on the drum surface. A thermocompression peeling roll is provided, which is in sliding contact with the drum, and which laminates a carrier film on the copper foil that has been roughened, washed with water, and dried, and peels the copper foil together with the carrier film from the drum surface and presses it. An apparatus for producing an ultra-thin copper foil laminate, characterized in that a pair of laminating rolls are provided for laminating a carrier foil for ultra-thin copper foil under pressure on the shiny side of the copper foil laminate thus obtained.