JP4345999B2 - Copper plating method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a copper plating method capable of performing copper plating with high adhesion to a nickel plated roll.
[0002]
[Prior art]
Conventionally, the plate making roll is manufactured by subjecting an iron roll base material to cylindrical polishing with a No. 220 to No. 320 polishing grindstone and further degreasing and then applying nickel plating to a thickness of 2 to 3 μm, or Then, the aluminum roll base material was cylindrically polished with a 220-320 polishing grindstone and then plated with nickel so as to have a thickness of 2-3 μm. Subsequently, copper plating was applied to a thickness of 100 μm, for example.
In the conventional copper plating method, the plate-making roll with nickel plating is rotatably chucked at both ends and placed in the plating bath, and then the copper-plating solution is put into the plating bath and it takes about 1 minute to immerse the plate-making roll. Then, after applying the rotation, the plating current was applied so that a voltage of about 15 V was applied, and the copper plating was performed.
Then, after removing the copper-plated skin by cylindrical polishing with a 320th polishing grindstone, the number of the polishing grindstone is, for example, 500-800-1200-1200-2000-2,500-3000 As described above, each polishing grindstone was sequentially cylindrically polished by a normal polishing method to obtain a mirror-finished finish.
[0003]
[Problems to be solved by the invention]
As described above, it takes too much time to start cylindrical polishing from the 320th polishing grindstone. In order to shorten the time, the present inventor applied nickel plating to a thickness of 2 to 3 μm after cylindrical grinding of an iron or aluminum roll base material with a number 800 polishing grindstone, and then, for example, thickness Copper plating was applied so as to be 100 μm.
Thereafter, the surface of the copper plating is removed by cylindrical polishing with an 800 polishing grindstone, and then the grinding method according to the applicant's patent application is adopted. No.-3000 No.-4000 No.-4000 No., etc. By adopting a polishing method in which each of the count polishing grindstones is cylindrically polished to bring it to a mirror-finished finish, the plate is made with two opposing No. 800 polishing grindstones. Cylindrical polishing was started by removing the copper-plated skin with a No. 800 polishing grindstone by polishing by applying a polishing pressure across the roll.
[0004]
However, the copper plating was peeled off from the nickel plating surface as if it were ballad plating.
As a result of diligently searching for the cause, the polishing before the nickel plating was changed to 320 to 800, so that the surface roughness became extremely smaller than before, and the polishing method after the nickel plating was One of the reasons was that the polishing pressure increased due to the change, but the biggest cause was that a peelable boundary film was formed between nickel plating and copper plating.
More specifically, in recent years, in order to improve workability, plating is performed by adding a brightening agent or a hardener in a copper plating solution. Before the copper plating is performed on the nickel plating surface, the nickel plating is performed. Sulfur compounds contained in brighteners and hardeners (for example, Bis.S.Propyl.Sulfonate.Na) and dimercapto.monomethyl.imidazole [2Mercapto1Methyl] Imidazole]) was found to form a peelable boundary membrane.
[0005]
The present invention has been devised in view of the above points, and before the copper plating is performed on the nickel-plated surface, the peelability of the sulfur-based compound contained in the brightener or hardener on the nickel-plated surface. Even if a large polishing pressure is applied by increasing the adhesion between the nickel plating surface and the copper plating surface so that the boundary film is not formed, the copper plating peels off from the nickel plating surface as if it were ballad plating. It is an object of the present invention to provide a copper plating method that prevents this from happening.
[0006]
[Means for Solving the Problems]
In the present invention, after a nickel plated roll is placed in a plating bath, it is contacted with a copper plating solution in a state where it is rotated by applying 1 V to 5 V, and then copper plating is applied to the entire circumferential surface. A copper plating method characterized by increasing the liquid level, gradually increasing the voltage, and performing copper plating so that the plating voltage becomes 15 V when the roll is completely immersed. It is to provide.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
A copper plating method according to the present invention will be described through explanation of a method for producing a plate-making roll.
(1) Polishing of a roll base material A pre-made roll is manufactured by subjecting a roll base material made of iron or aluminum to cylindrical polishing by a normal polishing method using a number 320 polishing grindstone, and then using a number 320 polishing grindstone. A polishing method (for example, Japanese Patent Application No. 11-74433, Japanese Patent Application No. 11-74279) is employed to perform surface roughness miniaturization polishing, and then a special polishing method is applied with an 800 or 1000 polishing grindstone. Adopted for surface roughness miniaturized polishing.
(2) Nickel plating For example, nickel plating is applied to a thickness of 2 to 3 μm.
After the plate-making roll is chucked at both ends and placed in the plating bath, a nickel plating solution is put into the plating bath and the plate-making roll is immersed in the plating solution, and then rotated to apply a voltage of 15 V for plating.
In order to apply nickel plating to the iron roll base material, a degreasing treatment is performed as a pretreatment. Further, in order to apply nickel plating to an aluminum roll base material, for example, a zincate treatment is performed as a pretreatment to form an interface thin film that improves adhesion.
(3) Copper plating For example, copper plating is applied to a thickness of 100 μm.
As shown in FIG. 1A, after the plate-making roll R is chucked at both ends and positioned in the plating bath 1, it is rotated by applying a low voltage (for example, 1 V to 5 V) that does not cause electric burning. Then, the level of the copper plating solution in the plating bath is slowly raised, and the plate surface roll R is brought into contact with the level of the copper plating solution 2 to apply copper plating to the entire circumferential surface. Since the plating current flows at the moment when the copper plating solution 2 comes into contact with the plate-making roll R, the copper plating adheres instantaneously, and the reaction rate at which the sulfur-based compound contained in the brightener or hardener adheres is slow. The sulfur compound does not form a boundary film between nickel plating and copper plating. Also, because of the low voltage, the copper plating does not burn.
Thereafter, as shown in FIG. 1 (b), the level of the copper plating solution is raised and the voltage is gradually raised so that the plating voltage becomes 15V when the roll is completely immersed. In this manner, copper plating is performed. In this case, the sulfur-based compound is incorporated into the copper plating, but does not give peelability to the copper plating.
(4) Polishing of copper plating The surface of the copper plating is removed by ordinary cylindrical polishing with a polishing grindstone No. 1000, and then a special polishing method is employed to polish the surface roughness to a minimum with the polishing grindstone. Subsequently, the surface roughness is minimized by employing a special polishing method with a 1800 polishing grindstone. Subsequently, a special polishing method is employed with a No. 3000 polishing grindstone to perform surface roughness miniaturization polishing. Subsequently, cylindrical polishing is performed with a No. 4000 polishing grindstone, and then mirror polishing is performed with the polishing grindstone using another special polishing method.
The pre-made roll produced as above is
(A) A photosensitive film is applied and exposed to form a latent image, developed and etched to remove the resist and chrome plating,
(B) Apply a black resist and ablate the black resist with a yag laser, remove the black resist by etching and chrome plating,
(C) Engraving with an electronic engraving machine and chrome plating,
A plate roll.
[0008]
【The invention's effect】
According to the copper plating method of the present invention, a nickel-plated roll is brought into contact with a copper plating solution in a state of being rotated by applying a low voltage that does not cause electric burning. Is increased to the plating voltage and thick copper plating,
Before the copper plating is performed on the nickel plating surface, the nickel plating surface and the copper plating are not formed on the nickel plating surface without forming a peelable film of a sulfur compound contained in a brightener or a hardener. The adhesion with the surface can be dramatically increased. Therefore, even if the surface of the nickel plating surface where the copper plating is deposited is changed from 320 to 800 or 1000, the biting force of copper plating against nickel plating is sufficiently large. Therefore, even if the polishing roll is sandwiched between two polishing wheels and a large polishing pressure is applied to perform cylindrical polishing, the copper plating does not peel off from the nickel plating surface as if it were ballad plating.
[Brief description of the drawings]
FIG. 1A is a schematic front view showing the start of copper plating, FIG. 1B is a schematic front view showing a plating state after a predetermined time has elapsed since the start of copper plating,
[Explanation of symbols]
Plate making roll ... R
Copper-plated bathtub ... 1
Copper plating solution 2

Claims (1)

After the nickel plated roll is positioned in the plating bath, it is contacted with the copper plating solution in a state where it is rotated by applying 1V to 5V, and copper plating is applied to the entire circumferential surface. A copper plating method characterized by performing copper plating so that the voltage is gradually increased and the voltage is gradually increased so that the plating voltage becomes 15 V when the roll is completely immersed .

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