JP2845172B2 - Electroforming equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an electroforming apparatus,
In particular, it relates to an electroforming apparatus for a stamper for producing an optical recording medium.

[0002]

2. Description of the Related Art In manufacturing an optical recording medium for recording / reproducing information by changing optical characteristics by irradiating an optical beam, an information pit or a concave / convex pattern of a guide groove to be recorded first is formed. A stamper on which a pattern of concavo-convex is transferred is manufactured from the master thus obtained by using, for example, an electroforming apparatus disclosed in JP-A-4-238129.

A conventional electroforming apparatus will be described in detail with reference to FIG.

FIG. 3 is a sectional view showing a conventional electroforming apparatus.

[0005] In a resin-made electroforming tank 1 such as polypropylene or vinyl chloride, boric acid having a concentration of 35 g / L to 40 g / L and various additives are dissolved in nickel sulfamate having a concentration of 450 g / L to 480 g / L. The electroforming liquid 2 is filled. A master 5 engraved with information to be recorded and irregularities in a guide groove, which has been subjected to a conductive treatment beforehand on the cathode 4 at the tip of the rotating shaft 3 in the electroforming liquid 2.
And nickel ions are electrolyzed into the electroforming solution 2 from the anode 6 provided at a position facing the cathode, and the nickel ions are deposited on the master.

In order to supply nickel ions from the anode 6,
The anode 6 itself is made into a basket-like basket, into which nickel-nickel or nickel fragments 7 in the form of pellets are put, and nickel electricity is electrolyzed in the electroforming liquid 2 when electricity is supplied.

Here, the electroforming liquid 2 is discharged from a discharge port 8 defining a liquid level, passes through a pipe 22, and passes through a piping system having a liquid temperature control unit 10. The electroforming liquid 2 is sent out by the pump 11, passes through the filter 12 for filtering impurities, and circulates through the outlet 23 to the electroforming tank 1.

As the cumulative electroforming time increases, insoluble metal dust (slime, sludge) is generated in the nickel or nickel pieces 7 in the form of pellets of the anode 6 and adheres to the surface. Due to the adhesion, the energization efficiency between the anode 6 and the cathode 4 is reduced, and the thickness distribution in the radial direction of the electroformed plate after electroforming the master 5 shows an unintended distribution tendency, warpage occurs,
There is a tendency that the mechanical properties of the electroformed plate are deteriorated, such as that the surface hardness and the back surface hardness of the electroformed plate become hard and the surface roughness of the back surface of the electroformed plate becomes rough. If insoluble metal dust (slime, sludge) adheres to the pellet-like nickel or nickel fragments 7 of the anode 6, the pellet-like nickel in the anode 6 is removed from a vibrator 18 fixed to a place such as the anode 6. Ultrasonic waves were radiated to the nickel or nickel fragments 7 to perform cleaning for a predetermined time.

[0009]

In the above-mentioned conventional electroforming apparatus, the ultrasonic wave is applied to the pellet-like nickel or nickel fragments in the anode by the vibrator. When radiation is performed and cleaning is performed for a predetermined time, insoluble metal dust (slime, sludge) adheres to the filter and the vicinity of the filter portion, and the amount of adhesion increases according to the radiation time of the vibrator. Due to the circulation of the electroforming solution, the insoluble metal dust (slime, sludge) adhered to the electroforming solution is mixed into the electroforming solution, and the electroforming solution is directly poured onto the master from the outlet. Due to the insoluble metal dust (slime, sludge) in such an electroforming solution, in a conventional electroforming apparatus,
The thickness distribution in the radial direction of the electroformed plate after electroforming shows an unintended distribution tendency, warpage occurs, the surface hardness and the back surface hardness of the electroformed plate become hard, or the surface roughness of the back surface of the electroformed plate There is a disadvantage that the mechanical properties of the electroformed plate are deteriorated, for example, the degree of roughness is reduced.

[0010]

[Means for Solving the Problems]

(1) The electroforming apparatus of the present invention includes a vibrator that radiates ultrasonic waves to the anode, a dedicated bypass for guiding the electroforming liquid to the electroforming liquid when the vibrator ultrasonically cleans the anode, and a dedicated bypass for this. And a filter for exclusive use at the time of cleaning which is provided in the inside and exclusively removes metal dust from the anode. (2) An electroforming apparatus according to the present invention is characterized in that the vibrator according to (1) is made of quartz. (3) The electroforming apparatus according to the present invention is characterized in that SUS316 is attached to the surface of the vibrator made of quartz according to the above (2).

[0011]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the structure of an embodiment of an electroforming apparatus according to the present invention.

In a resin-made electroforming tank 1 such as polypropylene or vinyl chloride, boric acid having a concentration of 35 g / L to 40 g / L and various additives were dissolved in nickel sulfamate having a concentration of 450 g / L to 480 g / L. The electroforming liquid 2 is filled. A master 5 engraved with information to be recorded and irregularities in a guide groove, which has been subjected to a conductive treatment beforehand on the cathode 4 at the tip of the rotating shaft 3 in the electroforming liquid 2.
And nickel ions are electrolyzed into the electroforming solution 2 from the anode 6 provided at a position facing the cathode 4 to deposit nickel ions on the master.

In order to supply nickel ions from the anode 6,
The anode 6 itself is made into a basket-like basket, into which nickel-nickel or nickel fragments 7 in the form of pellets are put, and nickel electricity is electrolyzed in the electroforming liquid 2 when electricity is supplied.

Here, the electroforming liquid 2 is discharged from a discharge port 8 that defines a liquid level, passes through a pipe 9, and passes through a piping system having a liquid temperature control unit 10. The electroforming liquid 2 is sent out by a pump 11, passes through a filter 12 for filtering impurities, and circulates through the outlet 13 to the electroforming tank 1.

As the cumulative electroforming time increases, insoluble metal dust (slime, sludge) is generated in the pellet-like nickel or nickel fragments 7 of the anode 6 and adheres to the surface. The attached insoluble metal dust (slime, sludge) needs to be washed.

When not electroformed, the valve 14 is opened,
The valve 15 is closed, the electroforming liquid 2 is circulated through the bypass 16, and ultrasonic waves are radiated from the vibrator 18 fixed to the anode 6 to the nickel or nickel pieces 7 in the form of a pellet in the anode 6 to perform cleaning for a predetermined time. .

At this time, insoluble metal dust (slime, sludge) adhering to the pellet-like nickel or nickel fragments 7 floats in the electroforming liquid 2 by ultrasonic waves from the vibrator 18 and Bypass 16 by circulation of liquid 2
Through the filter 17 at the time of washing.

The vibrator is disposed on the front and back surfaces, the side surfaces, the upper and lower surfaces, and the inside of the basket of the anode 6 in order to enhance the cleaning effect of the nickel or nickel fragments 7 in the form of pellets. The surface facing the cathode 4 is for the propagation of nickel ions, and the upper surface is for putting in and taking out nickel or nickel fragments 7 in the form of pellets at the time of maintenance.
The greater the number of vibrators, the higher the cleaning effect. However, considering the cost, it is sufficiently effective to install them on the back and inside.

The vibrator is made of quartz to prevent corrosion by the electroforming solution 2 and electrodeposition of nickel. Since the vibrator installed inside the basket is in direct contact with nickel or a piece of nickel in the form of a pellet, a metal such as SUS316 is attached to the surface to prevent breakage.

The oscillation conditions are as follows: an oscillation frequency of 50 kHz, an oscillation output of 300 W, and an oscillation time of 5 to 10 minutes. The circulation of the electroforming liquid 2 is performed for about 1 hour after the oscillation is completed, and a sufficiently insoluble metal dust (slime) is formed. , Sludge) could be filtered.

Next, the washing after the filtration will be described in detail with reference to FIG.

FIG. 2 is a sectional view of the filter for exclusive use at the time of cleaning of the electroforming apparatus of FIG.

The valve 14 is closed, a section closed by the valve 14 is formed in the bypass 16, the filter housing lid 20 for cleaning is removed from the filter housing 17 for cleaning, and the filter 19 for cleaning is taken out from the inside. The number of filters 19 for cleaning only, which is specified by the number of filter housings 17 for cleaning, is used, and has an acid-resistant pore size of 10 μm. As the valve 14, a three-way ball valve is used, and the valve 14 is opened so that the liquid in the closed section of the bypass 16 described above flows out.
The inner wall of the closed section of the bypass 16 and the inner wall of the filter housing 17 at the time of cleaning are cleaned by introducing a weakly acidic solution 21. As the weakly acidic solution 21, 1N hydrochloric acid is used. The cleaning time is about 10 minutes.

[0025]

As described above, the electroforming apparatus of the present invention uses the method of radiating ultrasonic waves to vibrate the nickel or nickel pieces in the anode basket, thereby forming the pellets. By simply washing nickel or nickel fragments with a weakly acidic solution and pure water, it is possible to remove deposits that did not completely disappear, improve the current-carrying efficiency, and improve the radial thickness distribution and warpage of the electroformed sheet. This has the effect of increasing the stability of electroformed plate mechanical characteristics such as surface hardness, back surface hardness, and surface roughness of the electroformed plate back surface.

Conventionally, when a method of radiating ultrasonic waves to vibrate nickel or nickel pieces in the form of pellets in an anode basket, insoluble metal dust (slime, sludge) is found around the filter or the filter portion. The adhered insoluble metal dust (slime, sludge) is mixed into the electroforming solution by the circulation of the electroforming solution, so that the thickness distribution, warpage, surface hardness and surface hardness of the electroformed sheet in the radial direction are obtained. Backside hardness,
Deterioration of electroformed plate mechanical characteristics such as the surface roughness of the back of the electroformed plate has occurred. The electroforming apparatus according to the present invention is provided with a filter for exclusive use during cleaning that exclusively removes metal dust from the anode, so that insoluble metal dust (slime, sludge) adheres and mixes again into the electroforming solution. This has the effect of preventing the above-described deterioration of the electroformed sheet mechanical properties and increasing the stability of the electroformed sheet mechanical properties.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an electroforming apparatus according to the present invention.

FIG. 2 is a cross-sectional view of a filter dedicated for cleaning of the electroforming apparatus of FIG. 1;

FIG. 3 is a sectional view showing a conventional electroforming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electroforming tank 2 Electroforming liquid 3 Rotating shaft 4 Cathode 5 Master 6 Anode 7 Nickel or nickel fragment in pellet form 8 Outlet 9 Piping 10 Temperature control unit 11 Pump 12 Filter 13 Blow-out port 14 Valve 15 Valve 16 Bypass 17 Cleaning Filter housing 18 vibrator 19 filter for cleaning 20 filter housing lid for cleaning 21 weakly acidic solution 22 piping 23 outlet

Claims (3)

(57) [Claims] 1. A vibrator for radiating ultrasonic waves to an anode, a dedicated bypass for guiding an electroforming solution when the vibrator ultrasonically cleans the anode, and a metal provided in the dedicated bypass and from the anode. An electroforming apparatus comprising: a filter for exclusive use at the time of cleaning for exclusively removing dust. 2. The electroforming apparatus according to claim 1, wherein said vibrator is made of quartz. 3. A SUS surface is formed on the surface of the vibrator made of quartz.
3. The electroforming apparatus according to claim 2, further comprising: 316.