JPH036391A - Electrocasting device - Google Patents

Abstract

PURPOSE:To rapidly carry out electrocasting and to improve its workability at the time of forming a metallic film on a glass master disk coated with an oxide film in the production process of a stamper for the information recording medium by electrocasting by forming a layer on the surface of an electrocasting soln. with a float to prevent the vaporization of water from the electrocasting soln. surface. CONSTITUTION:A photoresist 8 is applied on a glass substrate 9, a fine pattern 8' is formed to obtain a glass master disk 6, a conductive film 11 of Ag or Ni is formed on the surface, a metallic film 12 is then formed by electrocasting, and the conductive film 11 and metallic film 12 are peeled from the disk 6 to form a stamper 13 for the information recording medium. When the metallic film 12 is formed by electrocasting in this process, many floats 14 of sensor balls, etc., are arranged on the entire surface of the electrocasting soln. 7 of nickel sulfamate. Consequently, water is not vaporized from the surface of the soln. 7, the composition and temp. of the soln. are stabilized, adjustment of the soln. composition is not needed, and electrocasting is stably and rapidly carried out.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a stamper for forming information recording media for duplicating information recording media such as optical carts, optical discs, and magneto-optical discs for recording and reproducing information. This relates to electroforming equipment used in manufacturing.

[Prior art] Conventionally, stampers for forming information recording media are usually manufactured by Japanese Patent Application Laid-Open No. 6
Manufactured by methods such as those described in Publication No. 1-284843, Publication of Utility Model Application Publication No. 141435/1983, and ``Key Points of Optical Disk Process Technology No. 54 (Japan Industrial Technology Center, published in March 1985). There is.

Specific methods include those shown in FIGS. 5(a) to 5(e). This figure is a process diagram showing a method of manufacturing a stamper for forming an information recording medium by a general electroforming method. In the process diagram, 9 is a glass substrate such as blue plate glass, 8 is a photoresist for patterning on the glass substrate, and 8' is a tracking groove obtained by exposing and developing the photoresist, and an information bit. 6 is a glass master disc obtained by forming a fine pattern of irregularities such as tracking grooves, information bits, etc. on a glass substrate; 11 is a glass master plate in which a metal film is formed by electroforming on the glass master disc; 6' is a glass master disk with a conductive pattern 1 formed on a glass master disk with a fine pattern of irregularities such as tracking grooves and information bits, 12 is a conductive film formed by electroforming. The metal film 13 formed on the glass master disc is a stamper for forming an information recording medium obtained by integrally peeling the conductive film and the metal film from the glass master disc at the same time.

In the manufacturing method of a stamper for forming information recording media by a general electroforming method, first, a photoresist 8 is coated on the surface of a glass substrate 9 (see FIG. 5(a)), and then a tracking groove and an information recording medium are formed. A glass master disk 6 is obtained by forming a fine pattern 8' of concavities and convexities such as a cutting bit. (Figure 5 (
b)) Next, after forming a conductive film 11 on this surface (see Fig. 5(c)), a metal film 12 is formed by electroforming (see Fig. 5(d)). By simultaneously peeling the chemical film 11 and the metal film 12 from the glass master 6, a stamper (mother,
Master) 13 is manufactured. (See Figure 5 (e)) The general electroforming process is as described above, and in particular, the electroforming process in Figures 5 (C) and (d) will be explained in detail. Figure 5 (C
) The conductive film 11 is formed by a method such as metal vapor deposition or sputtering in a vacuum, and silver, often nickel, is often used as the material. Then, using the sputter link method, 500~100 nickel is applied onto the fine pattern 8' of unevenness such as tracking grooves, information bits, etc.
It is common to form a film to a thickness of 1,000 mm.

Next, the electroforming process (Fig. 5(d)) begins, but in the preliminary stage, organic impurities contained in the nickel sulfamate electroforming solution are removed by periodic activated carbon treatment, and metal ions are removed. Electrolytic cleaning is used to segregate and remove it.

An example of the nickel sulfamate electroforming solution used here is as follows.

Boric acid [83803] 35-38 g
/j! Pit inhibitor 2.5 mR
/R pu of nickel sulfamate electroforming solution is usually 3 to 5
range is used, variations in pH generate internal strain,
Nickel bromide causes curling of the stamper.
It is adjusted by directly adding sulfamic acid, caustic soda, etc.

FIGS. 6(a) and 6(b) are process explanatory diagrams showing the configuration of a conventional electroforming method in a method of manufacturing a stamper for forming an information recording medium. In the figure, 7 is a nickel sulfamate electroforming solution for depositing nickel metal and performing electroforming, 4 is an electroforming tank for storing the nickel sulfamate electroforming solution, and 4' is a nickel sulfamate electroforming solution. Electroforming layer upper cover to prevent water evaporation of the liquid; 5 is a filter that circulates the nickel sulfamate electroforming liquid in the electroforming tank and removes dust, impurities, etc., and ■ is a conductive treatment. nickel chip for forming a metal film on the glass master; 2 is an oxidation tank for the nickel chip; and a tummy plate for electrolytic cleaning of the nickel sulfamate electroforming solution; 6'
3 is a glass master disk on which a conductive film is formed on a glass master disk with a fine pattern of irregularities such as tracking grooves and information bits, 3 is a motor for rotating the glass master disk on which a conductive film is formed, and IO is an electric motor. This heater is used to maintain the electroforming liquid of nickel sulfamate in the casting tank at a constant temperature. As shown in the figure, a spherical nickel chip 1 is used, and this nickel chip 1 always has a pH of
Since the nickel chip 1 is immersed in the electroforming solution 7 of nickel sulfamate 3 to 5, the surface layer of the nickel chip 1 is oxidized and discolored to brown. In this state, electricity is applied in the nickel sulfamate electroforming solution 7 using the nickel chip 1 as a positive electrode and the glass master plate 6' on which a conductive film is formed as a negative electrode.
When nickel metal is deposited and electroformed, the oxidized layer of the nickel chip is electroformed. Therefore,
It is necessary to remove this oxide layer, and the method for doing so is shown in FIG. 6(a).

First, in FIG. 6(a), electricity is applied in the nickel sulfamate electroforming solution 7 using the nickel chip l as a positive electrode and the dummy plate 2 with good conductivity such as copper as a negative electrode. An oxidized layer of the nickel chip 1 is deposited thereon, and at the same time the oxidized layer of the nickel chip 1 is removed, electrolytic cleaning of the nickel sulfamate electroforming solution 7 described above is performed.

Next, as shown in FIG. 6(b), using the nickel chip l as a positive electrode and the glass master disk 6' on which a conductive film has been formed as a negative electrode, the glass master disk 6' on which a conductive film has been formed is connected by the motor 3. While rotating, electricity is applied to the nickel sulfamate electroforming solution 7 to precipitate nickel metal onto the glass master disk 6' on which the conductive film has been formed, thereby performing electroforming.

Furthermore, while circulating the nickel sulfamate electroforming solution 7 in the electroforming tank 4, it is passed through a filtration filter 5 to remove dust and impurities. The liquid temperature is set at 45-55 by heating heater 10.
Maintained at the appropriate temperature of °C.

[Problems to be Solved by the Invention] However, in the above conventional example, the nickel sulfamate electroforming solution is heated to 45 to 55°C with a heating heater, and electricity is applied for 2 to 3 hours to deposit nickel metal. Since the stamper for molding information recording media is manufactured using the following method, there are the following drawbacks.

(1) Since stampers for forming information recording media are manufactured by applying electricity for 2 to 3 hours in a heated state (45 to 55°C), water in the nickel sulfamate electroforming solution evaporates and lO When cycled, the capacity of the nickel electroforming liquid tank is 4 to 6.
% pure water must be added.

(2) Each time an appropriate amount of pure water is added, the pH must be adjusted by directly adding nickel sulfamate tetrahydrate, boric acid, a pit inhibitor, caustic soda, etc.

(3) Water vapor accumulates between the electroforming tank top cover and the nickel sulfamate electroforming liquid, which adversely affects the power section of the motor's rotating shaft.

The present invention was made in view of such conventional electroforming equipment, and it is possible to remove sulfamine by providing a separation layer between the electroforming liquid and the air, or by providing a separation layer between the electroforming liquid and the air. It prevents the evaporation of moisture in the nickel acid electroforming solution, speeds up and simplifies electroforming work, and improves workability. It also allows the temperature and temperature distribution of the electroforming solution to be controlled, and the electroforming tank top lid and It is an object of the present invention to provide an electroforming device that can prevent water vapor from accumulating between the electroforming liquid of nickel sulfamate, and thus does not adversely affect the rotational power section of the motor.

[Means for Solving the Problems] That is, the present invention is an electroforming apparatus characterized in that, first, a plating material is disposed over the entire surface of the electroforming liquid.

Moreover, the second invention is an electroforming apparatus characterized in that a separation layer from air is provided on the surface of the electroforming liquid.

Furthermore, a third invention is characterized in that it includes a pump for air removal, a pump for circulating the electroforming liquid through a filtration filter, and a liquid adjustment tank, and is configured in a closed type. It is an electroforming device.

The present invention will be explained in detail below.

FIG. 1 is an explanatory diagram showing an example of the electroforming apparatus of the present invention.

In the figure, the electroforming apparatus of the present invention has a plating material 14 placed over the entire surface of the nickel sulfamate electroforming solution 7 to prevent moisture from evaporating from the surface. As the attachment material 14, for example, a sensor ball having a core material whose surface is coated with liquid crystal and coated with a resin is preferable, but the sensor ball is not necessarily limited thereto.

FIG. 2 is an explanatory diagram showing the structure of a sensor ball used in the electroforming apparatus of the present invention. In the figure, the sensor ball has a ball structure, and a liquid crystal 16 is coated on the surface of a hollow core material 21 which has a weight 0 15 inside to adjust the level of contact of the ball. A resin coating 17 is applied to the surface. The liquid crystal 16 is used for temperature distribution and temperature control, and the resin coach ink 17 is used to protect the liquid crystal applied to the surface of the floating ball from the nickel sulfamate electroforming liquid. When used as the sensor ball support material 14, it is possible to prevent water in the nickel sulfamate electroforming solution from evaporating from the liquid surface, and to control the temperature distribution and temperature of the electroforming solution.

Next, FIG. 3 is an explanatory diagram showing another example of the electroforming apparatus of the present invention. The electroforming apparatus shown in the figure is provided with a separation layer 18 from air on the surface of the electroforming solution. Separation layer 18 is collodion liquid and silicone oil.

It is made of a material selected from motor oil or a gel-like substance, and prevents water from evaporating from the liquid surface of the nickel sulfamate electroforming liquid 7.

Moreover, FIG. 4 is an explanatory view showing still another example of the electroforming apparatus of the present invention. The electroforming device shown in the figure is a closed type electroforming device, and includes a pump for air removal and a filtration filter 5.
A pump for circulating the electroforming liquid through the liquid adjustment tank 2
0, and 19 is an O-link (Piton: trade name) for preventing the nickel sulfamate electroforming solution from flowing into the motor.

[Examples] Hereinafter, the present invention will be explained in more detail based on Examples.

Example 1 First, a sensor ball with the structure shown in Figure 2 was created.

After setting and fixing a weight 15 such as a round ball inside the ball, a black ball of polyethylene acid was produced by blow molding. The appropriate size is 20 to 30 mm4) in diameter.

Next, liquid crystal 16 is applied to the surface of the float by dipping, spraying, or the like. Furthermore, in order to protect the liquid crystal 16, the sensor ball 14 was manufactured by further applying a coating with polyethylene resin. For example, resin coating may be carried out by using a sheet or film of resin to wrap and seal the floating ball coated with liquid crystal 16. In this case, vinyl chloride or polyester film was used as the resin.

The sensor ball manufactured in this way is used as a floating material 14.
An electroforming apparatus shown in FIG. 1 was created using the same.

An electroforming solution having the following composition was used as the nickel sulfamate electroforming solution.

Nickel sulfamate tetrahydrate [N1 (NH-poor SQ, )2-411201 5 (IQ
g#! Boric acid [H3Boff]
35-38 g/I! anti-pitting agent
2.5 mi)/J) The pH of the nickel sulfamate electroforming solution was 3 to 4, and the electroforming solution was heated at 45°C for 30 hours (10
The evaporation of water in the nickel sulfamate electroforming solution was within 0.5%, and even after 10 cycles of electroforming, the pH remained almost constant. There is no need to adjust the pH because it does not change.

Furthermore, the temperature distribution and temperature of the nickel sulfamate electroforming solution can be controlled using the liquid crystal of the sensor ball.

Example 2 As shown in FIG. 3, an electroforming device provided with a separation layer from air was created.

Silicone oil was provided at a thickness of 3 Pffl at the interface between air and the nickel sulfamate electroforming solution.

A stamper for forming an information recording medium was manufactured in the same manner as in Example 1 using the same nickel sulfamate electroforming solution as in Example 1.The evaporation of water in the nickel sulfamate electroforming solution was 0.3. %, and as in Example 1, the pH
There is almost no need for adjustment.

Example 3 As shown in FIG. 4, an electroforming device of a closed type was prepared in which generation of water vapor was prevented as much as possible.

In the figure, the air in the electroforming tank 4 and the nickel sulfamate electroforming solution 7 are caused to flow into the liquid adjustment tank 20 by a pump P1.

Next, the nickel sulfamate electroforming solution 7 from which dust and impurities have been removed is constantly supplied into the electroforming tank 4 by flowing out to the filter 5 by the pump P2. Motor 3 Are you worried about the inflow of nickel hesulfamic acid electroforming liquid 7? It is O-link 19 (Piton: product name)
This can be prevented by using

Further, liquid adjustment such as pH of the nickel sulfamate electroforming liquid 7 can be performed in the liquid adjustment tank 20.

[Effects of the Invention] As is clear from the above explanation, according to the electroforming apparatus of the present invention, a floating material consisting of a sensor ball with a liquid crystal applied to the surface of the floating ball and a resin coating applied thereon is coated with sulfamine. By disposing it on the entire surface of the acid nickel electroforming solution, the following effects can be achieved.

(1) Placing the sensor ball on the liquid surface prevents water evaporation of the nickel sulfamate electroforming solution, and the liquid crystal on the sensor ball allows the temperature distribution and temperature of the nickel sulfamate electroforming solution to be controlled. You can manage it.

(2) Nickel sulfamate nickel sulfamate 4
Since the work of directly adding water salt, boric acid, pit preventive agent, caustic soda, etc. and adjusting the pH is reduced, it is possible to speed up and simplify electroforming work, improving work efficiency. .

(3) Reliability can be improved because the temperature and temperature distribution of the nickel sulfamate electroforming solution can be constantly controlled.

(4) Since water vapor is prevented from accumulating between the electroforming tank top cover and the nickel sulfamate electroforming liquid, it does not adversely affect the power section of the motor rotating shaft.

Further, according to the electroforming apparatus of the present invention, the following effects can be achieved by providing a separation layer from air on the liquid surface of the nickel sulfamate electroforming solution or by making it a closed type.

(1) The evaporation of moisture in the nickel sulfamate electroforming solution can be prevented, and operations such as pH adjustment by directly adding nickel sulfamate 5 6 ・tetrahydrate, boric acid, pitting inhibitor, caustic soda, etc. As the cost decreases, it becomes possible to speed up and simplify electroforming work, improving work efficiency.

(2) Since it is possible to prevent water vapor from accumulating between the electroforming tank top cover and the nickel sulfamate electroforming liquid, it does not adversely affect the power section of the motor rotating shaft.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of the electroforming device of the present invention, FIG. 2 is an explanatory diagram showing the structure of a sensor ball used in the electroforming device of the present invention, and FIGS. 3 and 4 are each an explanatory diagram of the invention. 5(a) to (e) are process diagrams showing a method for manufacturing a stamper for forming an information recording medium by a general electroforming method, and FIG. 1A and 2B are process explanatory diagrams showing the configuration of a conventional electroforming method in a method of manufacturing a stamper for molding an information recording medium. ■...Nickel chip 2...Dummy plate 3...Motor 4...Electroforming tank 4'...Electroforming tank top lid 5...Filtration filter 6...Glass master 6'... Glass master plate 7 on which a conductive film is formed...Nickel sulfamate electroforming liquid 8...Photoresist 8'...Micro pattern of unevenness 9...Glass substrate 10...Heating heater 11...Conductive Chemical film 12...Metal film 13...Stamper for forming information recording medium 14...Flying material 15...Weight 16...Liquid crystal 17...Resin coach ink 18...Separation layer 19... ...0 link 20...Liquid adjustment tank 7 8 21...Core material 1

Claims (5)

[Claims] (1) An electroforming device characterized in that a float material is arranged on the entire surface of the electroforming solution. (2) The electroforming apparatus according to claim 1, wherein the floating material is a sensor ball having a liquid crystal coated on the surface of a core material and a resin coating applied thereon. (3) An electroforming device characterized in that a separation layer from air is provided on the surface of the electroforming liquid. (4) The electroforming apparatus according to claim 3, wherein the separation layer from air is made of a material selected from collodion liquid, silicone oil, motor oil, or a gel-like substance. (5) An electroforming device characterized by comprising a pump for air removal, a pump for circulating electroforming liquid through a filtration filter, and a liquid adjustment tank, and configured in a closed type.