JP2005029876A - Copper sulfate plating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method where a plating tank in which copper sulfate plating is performed using an insoluble anode and a dissolver in which copper as plating metal is dissolved to produce copper ions are provided and the feed of the copper ions made short is performed from the dissolver to the plating tank, and, characteristically, the production of the copper ions is promoted to maintain the copper sulfate plating for a long time. <P>SOLUTION: A roll to be engraved is dipped into a plating liquid of a plating tank, is rotated, and is subjected to copper sulfate plating using an insoluble anode. Further, metal copper is dipped into the plating liquid of a dissolver and is subjected to air stirring. The metal copper is dissolved by the synergism of free sulfuric acid and dissolved oxygen in the plating liquid to produce copper ions. The feed of the copper ions made poor is performed from the dissolver to the plating tank by a liquid feeding means. Further, the surplus liquid in the plating tank is returned to the dissolver by a liquid returning means, and copper sulfate plating is performed. Particularly, in the dissolver, the copper metal to be dipped into the plating liquid is brought into contact with a metal nobler than copper, and the dissolution of the copper is promoted to maintain the copper sulfate plating for a long time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes a plating tank that uses an insoluble anode and a dissolution tank that generates copper ions by melting copper, which is a plating metal, and supplies copper ions that are insufficient from the dissolution tank to the plating tank. In addition, the present invention relates to a copper sulfate plating method capable of maintaining the plating operation by increasing the production of copper ions in the dissolution tank.

The conventional copper sulfate plating method for a plate roll for gravure printing is carried out by placing a cassette type roll chuck rotating / conveying unit conveyed by a stacker crane on the main frame of the plating apparatus and chucking both ends by the cassette type roll chuck rotating / conveying unit. The plate-making roll for gravure printing connected to the cathode is immersed in a plating solution stored in a plating tank and rotated, and a plated metal copper ball immersed in the plating solution is used as an anode between the plate-making roll. This was a method of flowing a plating current.
Japanese Patent Laid-Open No. 11-061488 (copper sulfate plating method) JP 2003-166100 A (Plating method using insoluble anode)

  According to the conventional copper sulfate plating method for a plate roll for gravure printing (Japanese Patent Laid-Open No. 11-061488), black anode sludge adheres to the surface of the plated metal copper ball, and the stirring of the liquid and the plated metal copper ball are performed. As a result of dissolution, the anode sludge was separated from the plated metal copper ball, floated in the plating solution, and adhered to the surface of the plate-making roll, forming lumps and pits. Also, to avoid the plating metal copper balls from dissolving too much and the copper ion concentration in the plating solution being too high, it is not possible to perform appropriate copper sulfate plating. Maintenance with a copper ion concentration plating solution was necessary.

  In order to solve the above-mentioned problems, it was considered to adopt a technique of subjecting the object to be plated to copper plating using an insoluble anode. This method uses, for example, a titanium-coated catalyst as an insoluble anode, prepares a plating tank and a copper dissolution tank, dissolves the copper plating material in the dissolution tank, and plating this It is supplied to the electrolytic solution in the tank, and the plating treatment is performed by energizing between the insoluble anode and the object to be plated, which does not form anode sludge.

  The inventors of the present application are a synthesizing of a plating tank that performs copper sulfate plating using an insoluble anode, and metal sulfate, which is a plating metal, in a plating solution and agitated in air to dissolve free sulfuric acid and dissolved oxygen in the plating solution. A dissolution tank that dissolves metallic copper by action to generate copper ions (cations); a liquid supply means that supplies copper ions that are insufficient from the dissolution tank to the plating tank; and an excess liquid in the plating tank that is dissolved Prototype copper sulfate plating equipment with liquid return means to return to tank, and then place cassette type roll chuck rotating and conveying unit conveyed by stacker crane on plating apparatus main body frame to rotate and convey cassette type roll chuck A test plate roll for gravure printing, chucked at both ends by the unit, was immersed in a plating solution and tested to perform copper sulfate plating using an insoluble anode.

  According to the test results, no anode sludge was generated, so no adhesion of pits or pits was observed on the surface of the copper sulfate plating that was attached to the plate making roll, but the dissolution amount of the plated copper metal balls in the dissolution tank was too small. The copper ion concentration in the plating solution soon became too low to make copper sulfate plating.

  Accordingly, the present invention includes a plating tank that uses an insoluble anode and a dissolution tank that generates copper ions (cations) by melting copper, which is a plating metal. It is a copper sulfate plating method to supply, and it is a solution subject that the production | generation of copper ion in a dissolution tank can be enlarged and enlarged and a plating operation can be continued.

In the present invention, a cassette-type roll chuck rotating / conveying unit conveyed by a stacker crane is placed on a plating apparatus main body frame, and a plate-making roll for gravure printing that is chucked at both ends by the cassette-type roll chuck rotating / conveying unit is used as a cathode. Connected and immersed in the plating solution stored in the plating tank and rotated to perform copper sulfate plating using an insoluble anode, and immersed in the plating solution stored in the dissolution tank with metal copper, which is the plating metal, and stirred by air The metal copper is dissolved by the synergistic action of free sulfuric acid and dissolved oxygen in the plating solution to generate copper ions (cations), and the supply of copper ions from the dissolution tank to the plating tank is performed by the solution supply means. A copper sulfate plating method in which the excess liquid in the plating tank is returned to the dissolution tank by the liquid return means,
The solution can be achieved by a copper sulfate plating method characterized in that in a dissolution tank, metal copper immersed in a plating solution is brought into contact with a metal nobler than copper such as gold, platinum, palladium, etc. to promote dissolution of copper.

(1) Since no anode sludge is generated in the plating tank, there is no formation of pits or pits on the surface of the copper sulfate plating attached to the plate making roll, and a beautiful surface of copper sulfate plating can be formed. Is applied, even if the polishing allowance is small, it is possible to perform very good mirror polishing without any defects or pits, so that the plating thickness can be reduced, the plating time can be shortened, and the plate making failure is reduced.
(2) In the dissolution tank, it is easy to control the area of contact with the noble metal than copper such as plated metal copper ball gold, platinum, palladium, etc. Since the copper ion concentration in the plating solution can always be managed in an appropriate state, good copper sulfate plating can be maintained.

The gravure plate making process of the plate making roll includes, for example, roll loading, degreasing, water washing, pickling, water washing, ballad treatment, water washing, ballad copper plating, water washing, grinding stone polishing, water washing, photosensitive agent coating, and image printing using a laser exposure apparatus Development, water washing, etching, water washing, resist peeling, water washing, chrome plating, water washing, polishing, water washing, and carry-out processes.
The copper plating line constituting a part of the plate making line is preferably equipped with a stacker crane, and is provided with a degreasing device, a copper plating device, a developing device, a corrosion device, a resist stripping device, a chromium plating device, etc. in the crane traveling zone. The cassette-type roll chuck rotating conveyance unit having a pair of chuck cones and a waterproof cap for sealing the outside of each chuck cone chucks the chuck holes at both ends of the plate-making roll positioned horizontally, and rotates the cassette-type roll chuck. The transport unit is lifted by a stacker crane and transported from device to device. In the degreasing device, copper plating device, developing device, corrosion device, resist stripping device, and chrome plating device, a cassette type roll chuck rotary transport unit is placed. The cassette type roll chuck is chucked by the rotary conveyance unit. It is a configuration that can handle a plate-making roll.
Therefore, it is preferable that the copper sulfate plating method of the present invention has a configuration in which the cassette-type roll chuck rotating and conveying unit can be adapted.
Specifically, the copper sulfate plating apparatus is a plating tank that performs copper sulfate plating using an insoluble anode, and the free sulfuric acid in the plating solution is obtained by immersing metal copper, which is a plating metal, in the plating solution and stirring the air. A dissolution tank that dissolves metallic copper by a synergistic action with dissolved oxygen and generates copper ions (cations); a liquid supply means that supplies copper ions that are insufficient from the dissolution tank to the plating tank; and A liquid return means for returning excess liquid to the dissolution tank, and in particular, a cassette-type roll chuck rotary transport unit transported by a stacker crane is placed on the plating apparatus main body frame, and the cassette-type roll chuck A gravure printing plate roll chucked at both ends by a rotary transport unit is immersed in a plating solution stored in a plating tank, and copper sulfate plating is performed using an insoluble anode. It is preferably made of sea urchin.
In the copper sulfate plating method of the present invention, the metal copper immersed in the plating solution is brought into contact with a noble metal such as gold, platinum, palladium and the like in the dissolution tank, and the air is stirred in such a configuration. It is preferable that it is comprised so that melt | dissolution of copper may be accelerated | stimulated.

FIG. 1 shows a plating apparatus to which a cassette-type roll chuck rotating and conveying unit substantially the same as the cassette-type roll automatic detaching apparatus shown in Japanese Patent Publication No. 57-36995 can be applied. Plating is carried out by placing the roll-roll chuck rotary conveyance unit U.
More specifically, when the cassette-type roll chuck rotary conveyance unit U is placed on the plating apparatus main body X, the cassette-type roll is placed on the chain 2 of the chain winding apparatus driven by the motor 1 provided in the plating apparatus main body X. The sprocket 4 fitted and fixed to the spindle 3 on the driving side of the chuck rotation conveyance unit U is engaged.
The cassette-type roll chuck rotating and conveying unit U is provided at both ends of the plate-making roll R by a pair of energizable roll chucks 7 and 8 provided at both ends of the pair of spindles 3 and 6 that are provided from both ends of the lifting frame 5 and face each other. And a pair of liquid-proof caps 9 and 10 fitted to the spindles 3 and 6 are moved to abut against the end face of the plate-making roll R to energize the roll chucks 7 and 8 which are energized. It is the structure which prevents the approach of a process liquid.
The plate-making roll R is rotated by driving the motor 1 and plating is performed by passing a plating current between the plate-making roll R and the insoluble anode 11.

  This copper sulfate plating method is a gravure printing in which a cassette type roll chuck rotary transport unit U transported by a stacker crane is placed on a frame F of a plating apparatus body X and chucked at both ends by the cassette type roll chuck rotary transport unit U. The plate making roll R for use is immersed in a plating solution 13 stored in a plating tank 12 to perform copper sulfate plating using the insoluble anode 11, and the plating solution 13 stored in a dissolution tank 14 also serving as a plating solution storage tank. Metal copper, which is the plating metal, is soaked in the air and stirred in the air to dissolve the plated metal copper ball 15 by the synergistic action of free sulfuric acid and dissolved oxygen in the plating solution to generate copper ions (cations), and check valve A plating tank 1 from a dissolution tank 14 by a liquid supply means 16 comprising a liquid pumping port, a pump, a pipe, a flow control valve, a filter and the like. Together to supply the copper ions to be insufficient within, and is configured to return overflow scheme dissolving tank 14 the excess solution in the plating tank 12 by the liquid returning means 6.

After the cassette-type roll chuck rotating / conveying unit U is placed on the frame F of the plating apparatus main body X, a plating solution containing copper ions stored in the dissolution tank 14 by the liquid supply means 16 at an appropriate concentration is supplied to the plating tank 12. The plate-making roll R for gravure printing, which is chucked at both ends by the cassette-type roll chuck rotary conveyance unit U, is immersed in the plating solution stored in the plating tank 12.
After the level of the plating solution reaches a certain level, the plating solution is fed to the overflow troughs 12a provided at both ends of the plating tank 12 through the liquid return means (pipe) 17. And returned to the dissolution tank 14 by gravity. When finishing the plating, the valve 19 provided in the liquid drop pipe 18 connecting the plating tank 12 and the dissolution tank 14 is opened so that the plating solution in the plating tank 12 can be collected in the dissolution tank 14. It has become.

  The insoluble anode 11 is preferably a titanium plate coated with iridium oxide. The insoluble anode 11 is located on both sides of the plate-making roll R to be dipped in the plating solution and to be plated in the dissolution tank 1 and in the roll surface length direction. The required number is arranged at an appropriate pitch. Preferably, the insoluble anode 11 is configured to allow current to flow only in a portion corresponding to the length of the plate-making roll R.

A large number of resin pipes 20 are laid in a continuous state at the bottom of the dissolution tank 14, and a net-like body 21 made of a metal nobler than copper such as gold, platinum, palladium and the like is laid on the resin pipe 20. Further, the plated metal copper balls 15 are laminated on the mesh body 21, and the resin pipe 20 is connected to an air compressor (not shown) outside the tank, and the resin pipe 20 is provided with compressed air produced by the air compressor. The plating solution is configured to flow out from a large number of small holes into the plating solution and stir the plating solution. For example, it is assumed that the net-like body 21 has a large number of columnar portions 21 a and the contact area with the plated metal copper ball 15 is sufficiently expanded.
Accordingly, the copper metal is dissolved by the synergistic action of the free sulfuric acid in the plating solution and the dissolved oxygen replenished by the compressed air to generate copper ions (cations). In this case, the contact between the noble metal and the plated metal copper ball is ensured with a large area, so that the copper in contact with the noble metal than copper is charged positively and dissolved in the anodic copper. Dissolution is promoted.
Since it is easy to control the area in which the plated metal copper ball is brought into contact with a noble metal such as gold, platinum, palladium, etc. in the melting tank, the amount of dissolution of the plated metal copper ball can be controlled appropriately. Since the copper ion concentration in the plating solution can always be managed in an appropriate state, good copper sulfate plating can be maintained.
Since anode sludge does not occur in the plating tank, there is no formation of pits and pits on the surface of the copper sulfate plating attached to the plate making roll, and a clean surface copper sulfate plating can be formed, and electrolytic abrasive polishing is applied in plate making Even if the polishing allowance is small, it is possible to perform extremely good mirror polishing without any defects or pits, so that the plating thickness can be reduced, the plating time can be shortened, and the plate making failure is reduced.
[Experimental example]
When plating was performed by placing a platinum net 21 on the bottom of the dissolution tank 14, the copper dissolution rate was 0.84 g / L / h, and copper sulfate plating using an insoluble anode continued for a long time. I did it.
[Comparative Example]
When plating was performed by removing the platinum net 21 from the bottom of the dissolution tank 14, the dissolution rate of copper was 0.43 g / L / h, and the copper sulfate plating using the insoluble anode was slightly passed. I can no longer do it.

  The present invention also includes a plating method that does not use a cassette-type roll chuck rotary transport unit transported by a stacker crane. The present invention is also applicable to the case where the plating apparatus has chuck means for rotating the plate-making roll by chucking it and transfers the plate-making roll conveyed by an industrial robot. In addition, the plate making roll for gravure printing includes a type with a shaft. Further, the present invention is not limited to the net body 21 made of a metal nobler than copper on the resin tube 20. The resin tube 20 may be provided on the upper side of the mesh body 21. It is not limited to installing the dissolution tank 14 under the plating tank 12. Means for accommodating the plated metal copper balls 12 in the dissolution tank 14 can be appropriately provided.

1 is a schematic longitudinal front view of a copper sulfate plating apparatus for carrying out a copper sulfate plating method according to the present invention.

Explanation of symbols

U: cassette type roll chuck rotary conveyance unit, X: plating apparatus main body, F: frame of the plating apparatus main body, R: plate-making roll for gravure printing, 1 ... motor, 2. ..Chains, 3... Drive side spindle, 4... Sprocket, 5... Lifting frame, 6. Liquid-proof cap, 11 ... insoluble anode, 12 ... plating tank, 12a ... overflow, 13 ... plating liquid, 14 ... dissolution tank, 15 ... plated metal copper ball, DESCRIPTION OF SYMBOLS 16 ... Liquid supply means, 17 ... Liquid return means, 18 ... Falling-off pipe, 19 ... Valve, 20 ... Resin pipe, 21 ... The net-like body which consists of a metal more precious than copper 21a ... Columnar part,

Claims (1)

A plate roll for gravure printing is connected to the cathode, immersed in a plating solution stored in the plating tank and rotated to perform copper sulfate plating using an insoluble anode, and plated to the plating solution stored in the dissolution tank The metal copper, which is a metal, is soaked in air, and the copper is dissolved by the synergistic action of free sulfuric acid and dissolved oxygen in the plating solution to generate copper ions. A copper sulfate plating method in which the copper ion is supplied and the excess liquid in the plating tank is returned to the dissolution tank by the liquid return means,
A copper sulfate plating method characterized in that, in a dissolution tank, metal copper immersed in a plating solution is brought into contact with a noble metal such as gold, platinum, palladium and the like to promote dissolution of copper.

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