JPH0124870B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This invention relates to an electroforming mold and a method for manufacturing the same.

"Conventional Apparatus and its Problems" Conventionally, when producing an electroforming mold from a master mold having concave portions on its surface, when electrodeposition is carried out at a normal current density, as shown in FIG. The electrodeposited layer is formed thickly in the recess 3, which inhibits the growth of the electrodeposited layer in the recess 3. Therefore, the current density in the electroforming process is set lower than the usual current density, but on the other hand, it has the disadvantage that it takes many days to form the electrodeposited layer. Furthermore, even if the current density is lowered, it is unavoidable that the electrodeposited layer on the uneven parts 2 and 3 will be non-uniform, and for this reason, it is necessary to perform machining after the electroforming process, which requires a lot of time and effort. shall be.

In addition, for the purpose of correcting non-uniformity of the electrodeposition layer, an auxiliary electrode 8 is used as shown in Fig. 3. Since electrodeposition is carried out by rotating the electrode, there is a disadvantage that a lot of time is spent on the preparation of the auxiliary electrode and the attachment device.

"Purpose" The purpose of the present invention is to perform electrodeposition at high speed even in the recesses where the formation of the electrodeposition layer is slow, in the production of electroforming molds having complex uneven parts such as tooth patterns.

"Embodiment" An embodiment of the present invention will be described below with reference to the drawings.

That is, in FIG. 1, an electroforming master mold 1 is used for, for example, a tooth mold of a gear, and has a plurality of convex portions 2 and concave portions 3 formed on its surface. First, an electrodeposited thin film layer 4 with a thickness of 0.2 to 1 mm is formed on the surface of the matrix 1, and the thickness varies depending on the shape or size of the matrix 1. When forming, if the matrix 1 has a shape that allows electroplating, electroplating is more efficient, but if it is difficult to electroplat, or the plating process is If the process requires a relatively long time, it can be formed by electroless plating. Next, the electrodeposited thin film layer 4
Ceramic cement 5 is filled in the recess 3 on the surface of the mold 1, thereby making the surface of the mother mold 1 substantially uniform. Here Ceramic Cement 5
The main ingredient is a trivalent metal oxide such as aluminum oxide (Al ₂ O ₃ ) or nickel oxide (Ni ₂ O ₃ ) mixed with metal powder such as nickel, copper, aluminum, etc. at a weight ratio of 5 to 50%. It is composed of Since trivalent metal oxides have thermosetting properties, they are particularly suitable when the material of the matrix 1 is made of metal and can be heated at high temperatures.
Furthermore, since the metal powder mixed into the ceramic cement 5 has high thermal conductivity and electrical conductivity,
This has the effect of facilitating activation and bringing the thermal expansion of the ceramic cement 5 closer to the plating layer applied to its surface. Next, the ceramic cement 5 filled in the recess 3 is hardened, and at this time, in order to give conductivity to the ceramic cement, its surface is activated with palladium chloride (Pdcl ₂ ), tin chloride (Sncl ₂ ), etc. The thickness on its surface is about 0.01 ~
A plating layer 6 of about 0.1 mm is formed. Note that this plating layer is preferably formed by electroless plating. When this plating layer is formed, the surface of the mother mold 1 has no irregularities, so the surface is then processed by electrodeposition using a plating bath that can flow a high current, such as a nickel sulfamate bath. An electrodeposition layer 7 is formed thereon. As a result, an electroformed mold with a uniform surface is completed.

"Effects" As described above, this invention fills the concave portion of the matrix with ceramic cement containing a mixture of trivalent metal oxide and metal powder at a weight ratio of 5 to 50%, and
Since an electrodeposited layer is applied to the surface of this ceramic cement, it has good conductivity, and the thermal expansion of the ceramic cement and the plating layer applied to the surface can be made close to each other. Casting time is significantly reduced. In particular, according to this invention, the process time is one-third to two times the conventional time.
It can be shortened to one-fold. In addition, unlike conventional methods, there is no need to perform separate machining after electroforming, so the rotatability of electroforming equipment is improved, and the efficiency of electroforming is greatly improved by saving electricity costs and plating chemicals. There are advantages.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing an embodiment of the electroforming method according to the present invention, and FIGS. 2 and 3 are front sectional views showing a conventional processing method. 1... Mother mold, 2... Convex part, 3... Concave part, 4...
Electrodeposited thin film layer, 5... Ceramic cement, 6...
Metsuki layer.

Claims (1)

[Scope of Claims] 1. An electrodeposited thin film layer is formed on the surface of a matrix having uneven parts, and on the surface of the electrodeposited thin film layer, metal powder is added to trivalent metal oxide in a weight ratio of trivalent metal oxide to trivalent metal oxide in the recessed parts. Fill with ceramic cement mixed with 5 to 50%.
Activates the surface of Katsuko's ceramic cement,
A method for manufacturing an electroforming mold further comprising applying an electrodeposited layer to the surface of the ceramic cement. 2. An electrodeposited thin film layer is formed on the surface of the matrix having uneven parts, and on the surface of this electrodeposited thin film layer, 5 to 50% by weight of trivalent metal oxide and metal powder are mixed in the recessed parts. An electroforming mold characterized by being filled with a filler made of ceramic cement and having an electrodeposited layer on the surface of the filler.