JP3279776B2 - Porous electroformed mold and method for producing electroformed shell thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a porous electroforming mold used for a hollow mold or an injection mold for producing a plastic molded article, a press mold for producing a fibrous molded layer body, and a porous electroforming mold for the same. The present invention relates to a method for manufacturing an electroformed shell, and particularly to a method for manufacturing an electroformed shell having a thickness of 5 to 10 mm.

[0002]

2. Description of the Related Art In the electroforming mold described above, a conductive layer is formed on the surface of a model, and then the model is subjected to an electroforming process to form an electroformed shell of deposited metal. It is used for the main body. Since a mold having a complicated shape can be easily formed, it is used for a vacuum molding die and the like. This vacuum forming mold needs to be made porous so as to perform patterning under vacuum. Therefore, it has been known that a minute non-conductive portion is provided in a conductive layer on the surface of a model, and the non-conductive portion is not electroformed to form a large number of pores to make it porous.

[0003] Since this porous electroforming mold can easily form a mold having a complicated shape, it is attempted to expand the application to not only the vacuum molding die but also the above-mentioned hollow molding die, injection molding die and press die. Became.

[0004]

However, molds such as a hollow mold, an injection mold, and a press mold are molds to which a predetermined molding pressure acts during molding, and have a high pressure resistance and durability to the electroformed shell. Is required. Therefore, the thickness of the electroformed shell is inevitably increased to 5 to 10 mm. Note that the thickness of the vacuum forming die is as thin as about 5 mm.

As described above, when the thickness of the electroformed shell is increased, the following problems occur. The first problem is that pores for ventilation increase in thickness and are blocked by metal deposition. For this reason, the method of increasing the thickness and widening the pores as disclosed in Japanese Patent Publication No.
As in 63290, it is possible to apply a method of filling the space between the particle stacks with metal precipitation and eluting the particles to make the particles porous. But the strength is insufficient.

A second problem is that if the entire thickness of 5 to 10 mm is to be formed by electroforming, the plating time becomes longer, and the internal stress, which is a characteristic of the electroforming, increases as the thickness increases, and the distortion increases. Occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. It is an object of the present invention to provide a method in which even if an electroformed shell is thick, pores for ventilation are formed in the thickness direction. It is an object of the present invention to provide a porous electroforming mold having an opening in a predetermined shape with less distortion and a method for producing the electroformed shell.

[0008]

In order to achieve the above object, a porous electroforming mold is provided in which a gas-permeable backing layer is adhered to the back of an electroformed shell having a large number of pores penetrating from the surface to the back. An electroformed mold, wherein the electroformed shell comprises:
A first electroformed layer on the front side, a net of conductive metal attached to the back side of the first electroformed layer, the net and the first net;
It is a laminate including a second electroformed layer joined to the electroformed layer, wherein the pores of the electroformed shell are formed in a bead shape. On the back surface of the electroformed shell, irregularities of the net-like body are raised.

A method for producing an electroformed shell used in this porous electroforming mold is to apply a conductive paint to the surface of a model, and adhere a non-conductive spherical body in a satin pattern on the conductive paint. A second step of forming a first electroformed layer by electroforming, a third step of attaching a net to the first electroformed layer, and a first step of forming a first electroformed layer and the net by electroforming. and a fourth step of the laminated body to form a second electroformed layer on said second及
In the fourth step, the size of the non-conductive spherical body is
If less than the desired thickness, remove the model from the electrolyte.
Stick out and attach a non-conductive sphere on top of the non-conductive sphere.
And put it in the electrolyte and repeat the electroforming process
A method of forming an electroformed layer of a desired thickness by this, after forming the laminate , removing the laminate from the model, removing the remaining non-conductive sphere, and opening a large number of pores penetrating from the surface to the back surface. It is. The first step is a step of applying and drying a primary conductive paint on the surface of the model, a step of applying a secondary conductive paint in a satin pattern on the primary conductive paint, and before the secondary conductive paint dries. And attaching a non-conductive spherical body to the substrate.

[0010]

[Function] Since a laminated body is attached to the electroformed layer and is further integrally covered with the electroformed layer as it is, the electroformed layer is supported by the reticulated body, and the strength is increased to reduce distortion. Become. Since this net-like body emerges on the back surface of the electroformed shell, the adhesion to the backing layer is also improved.

Since the pores of the electroformed shell have a bead shape, the electroforming process is performed by continuously connecting non-conductive spherical bodies, so that the pores have the same shape even when the thickness is increased.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a main part of an electroformed shell used in a porous electroformed mold of the present invention, and FIG. 2 is a sectional view of the porous electroformed mold.

In the sectional view of the electroformed shell shown in FIG.
A backing layer 2 is lined on the back of the electroformed shell 1 for reinforcement. The electroformed shell 1 includes a first electroformed layer 11 formed by depositing a metal such as nickel or copper by electroforming.
, A net body 12 such as a brass net, and a second electroformed layer 13 of the same material as the first electroformed layer 11. The backing layer 2 is made of a metal-based granular material 1 of aluminum, nickel, zinc, or the like.
5 on the back side of the electroformed shell 1
5 and the electroformed shell 1 are bonded with a resin binder 16 such as an epoxy resin or a polyester resin, and have air permeability due to the presence of a space 17 between the metal-based particles 15.

In the surface view of FIG.
Is a grid metal wire mesh, and the brass wire 12a constituting the mesh
Are reinforcing members. The reticulated body 12 buried in the entire surface of the electroformed shell 1 contributes to an increase in the strength of the whole, and prevents generation of distortion against internal stress peculiar to the electroformed layer. Due to the presence of the net-like body 12, the thickness of the electroformed shell 1 is increased, and the electroforming time is shortened accordingly. Further, since the net-like body 12 is buried integrally in a joined state, a mesh pattern is protruded on the back side of the electroformed shell 1 and an uneven pattern is formed. By bonding the backing layer 2 to this uneven pattern, the peeling resistance between layers is improved.

The brass wire 12 constituting the mesh 12
Many pores 14 are open between a. In addition, although the pore directly under the brass wire 12a is closed as shown by a two-dot chain line, the closed pore is only a part and does not interfere with evacuation.

In the sectional view of the fine pores shown in FIG.
Reference numeral 4 denotes a continuous bead formed by pressing spheres, and penetrates from the surface of the electroformed shell 1 to the back in substantially the same shape. The pores 14 do not spread as they reach the back surface, and the proportion of the pores 14 in the electroformed shell 1 is minimal, and the strength of the electroformed shell 1 is not impaired by the presence of the pores 14. The diameter of the fine holes 14 is 0.1 to 0.3 mm, and 50 to 200 holes are opened per square centimeter, so that suction is possible without impairing the transferability of the surface.

A porous electroforming mold 5 using the above-described electroformed shell 1 will be described with reference to a sectional view of FIG. The backing layer 2 is filled in a container-shaped die plate 6 whose upper side is open, and the electroformed shell 1 corresponding to the lid is
And fixed. Since the molding material is pressurized in the recessed portion of the electroformed shell 1, pores 1 are formed in the recessed portion.
4 are provided. A pipe 7 that reaches the backing layer 2 is provided at an appropriate position on the die plate 6, and the pipe 7 is evacuated, cooled by passing cool air, and heated by passing hot air.

Next, a method of manufacturing the above-described porous electroforming mold will be described with reference to FIGS. 3 to 5
Shows a first step of forming a conductive layer having a minute non-conductive portion. As shown in FIG. 3, a model 20 (the reverse shape of the electroformed mold) having the same shape as the molded product is manufactured from an epoxy resin, a polyester resin, or the like. The primary conductive paint 21 is applied to the entire surface of the model 20 and dried. As the primary conductive paint 21, an epoxy paint containing copper or silver is used.

As shown in FIG. 4A, on the dried primary conductive paint 21, a desired range in which pore formation is required (portion protruding in a trapezoidal shape as shown in FIG. 4B). A secondary conductive paint is applied by spraying to form a pear-skin-like surface on which a large number of minute points adhere like an avatar on the surface of a pear. An acrylic paint containing copper or silver is used for the secondary conductive paint 22,
It is preferable that the primary conductive paint 21 can be clearly distinguished from the primary conductive paint 21 and can be easily applied in a satin pattern. Then, at the time of the electroforming process, the outer surface formed by the primary conductive paint 21 and the secondary conductive paint 22 becomes a peeling surface of the electroformed shell.

As shown in FIG. 5, before the secondary conductive paint 22 applied in a satin pattern is dried, the nonconductive spherical body 23 is brought into contact with the nonconductive spherical body 23 on the secondary conductive paint 22. 23 adheres. The non-conductive spherical body 23 is made of a styrene resin or an acrylic resin that can be dissolved with a solvent, and has a diameter of 20 mm.
Those having a size of 0 to 500 microns are used.

FIG. 6 shows a second step of forming the first electroformed layer. The model 20 formed in the first step is immersed in the electrolytic solution 30, the electrode 31 of nickel, copper or the like in the electrolytic solution 30 is connected to the positive electrode, and the primary conductive paint 21 is connected to the negative electrode to energize. An electroforming process is performed. Metals such as nickel and copper are deposited on the primary conductive paint 21 and the secondary conductive paint 22 on the surface of the model 20 to form a first electroformed layer 24. However, since no metal is deposited on the nonconductive spherical body 23 and the base of the pores is formed, the thickness of the first electroformed layer 24 is limited to such a degree that the nonconductive spherical body 23 is exposed. .

If the size of the non-conductive spherical body 23 is smaller than the desired thickness of the first electroformed layer 24,
Is taken out of the electrolytic solution 30, the non-conductive spherical body 23 is further adhered on the non-conductive spherical body 23 with a solvent or the like, and the non-conductive spherical body 23 is put into the electrolytic solution 30 and electroformed again. By repeating this, the first electroformed layer 24 having a desired thickness is obtained.

FIG. 7 shows a third step of attaching the mesh. A conductive net 25 such as a brass net is attached to the surface of the first electroformed layer 24 by spot welding or bonding a brass wire. This net-like body 25 is a first electroforming device 2
4 is attached so as to cover the entire surface, and has a grid shape as shown in the figure, and serves as a core material for reinforcement.

FIG. 8 shows a fourth step of forming the second electroformed layer. The model 20 formed in the third step is immersed in the electrolytic solution 30 and subjected to an electroforming process. First electroformed layer 24
And the second electroformed layer 26 integrally joined on the net 25
Is formed. A mesh 25 for reinforcement is embedded in the second electroformed layer 26 to bear external or internal stress and prevent generation of distortion. The non-conductive spherical body 23 is further adhered on the non-conductive spherical body 23 with a solvent or the like to form the second electroformed layer 26.
Is appropriately increased.

Then, the above-described third and fourth steps are repeated until the electroformed layer reaches a desired thickness, thereby forming a laminate of the electroformed layer and the mesh. Next, the model 20 is
Then, the laminate is released from the model 20. At this time, the primary conductive paint 21 and the secondary conductive paint 22 of the model 20 are used.
Becomes an exfoliated surface, and the nonconductive spherical body 23 remains in the laminate.

When the nonconductive spherical body 23 remaining in the laminate is extracted and removed with a solvent or the like, an electroformed shell in which beads are formed can be obtained. Using this electroformed shell as a mold body, a porous electroformed mold 5 as shown in FIG. 2 is manufactured.

[0027]

According to the porous electroforming mold of the present invention, a mesh for reinforcement is integrally embedded in the electroformed layer.
Because the mesh resists the internal stress peculiar to the electroforming process, the strain is reduced even if the electroformed layer is thickened, and an electroformed shell having a thickness of 5 to 10 mm and having excellent durability and pressure resistance is used. It becomes possible. Since the irregularities are raised on the back surface of the electroformed layer by the mesh, the deviation between the backing layer and the electroformed layer is prevented by the irregularities, the two layers are sufficiently bonded, and the occurrence of delamination can be prevented. Further, the pores are cascading, and by connecting pores of a predetermined size in the thickness direction, 5 to 5
Even if it has a thickness of 10 mm, the pores having a predetermined diameter can be penetrated from the front surface to the back surface of the electroformed shell without being closed and expanded.

Further, the method for producing an electroformed shell according to the present invention comprises:
A non-conductive sphere is attached on the conductive paint in a satin pattern, and if necessary, a non-conductive sphere is further attached on the non-conductive sphere. Becomes possible. The size of the pores is determined by the size of the non-conductive spherical body, and the diameter of the pores can be arbitrarily selected. Also, when the conductive paint is combined with the primary conductive paint and the matte secondary conductive paint,
The portion where the pores are provided can be arbitrarily selected, and it is possible to cope with the formation of an electroformed shell having a complicated shape. Further, a net is buried in the conductive layer, and the thickness can be increased by the amount of the net, so that the electroforming time for obtaining an electroformed layer having a desired thickness can be shortened.

[Brief description of the drawings]

FIG. 1 is a view showing a main part of an electroformed shell used in a porous electroformed mold of the present invention.

FIG. 2 is a sectional view of a porous electroforming mold.

FIG. 3 is a view showing a first step of manufacturing an electroformed shell of the present invention.

FIG. 4 is a view showing a first step of manufacturing an electroformed shell of the present invention.

FIG. 5 is a diagram showing a first step of manufacturing an electroformed shell of the present invention.

FIG. 6 is a view showing a second step of manufacturing the electroformed shell of the present invention.

FIG. 7 is a view showing a third step of manufacturing the electroformed shell of the present invention.

FIG. 8 is a view showing a fourth step of manufacturing the electroformed shell of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electroformed shell 2 backing layer 5 porous electroformed mold 11, 24 first electroformed layer 12, 25 mesh body 13, 26 second electroformed layer 14 pores 20 model 21 primary conductive paint 22 secondary conductive paint 23 Non-conductive sphere

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shu Yokoyama 7-6-6 Matsugaoka, Kakamigahara City, Gifu Prefecture (72) Inventor Hiroto Nagaoka 1-11-11 Momokaoka, Komaki City, Aichi Prefecture (58) Fields surveyed (58) Int.Cl. ⁷ , DB name) C25D 1/00 B29C 33/38 C25D 1/08

Claims (4)

(57) [Claims] 1. A porous electroforming mold in which a gas-permeable backing layer is adhered to a back surface of an electroformed shell having a large number of pores penetrating from a surface to a back surface, wherein the electroformed shell has a surface side. A first electroformed layer, a net of conductive metal attached to the back side of the first electroformed layer, and a second electroformed layer joined to the net and the first electroformed layer. A porous electroforming mold in which the electroformed shell is a laminate and the pores of the electroformed shell are formed in a bead shape. 2. A pre-Symbol electroforming claim 1 porous electroformed mold, characterized in that stand out irregularities of the mesh body on the back of the shell. 3. A first step in which a conductive paint is applied to the surface of the model and a non-conductive spherical body is adhered on the conductive paint in a satin pattern, and a first step in which a first electroformed layer is formed by electroforming. A second step, a third step of attaching a net on the first electroformed layer, and a fourth step of forming a second electroformed layer on the first electroformed layer and the net by electroforming to form a laminate. And the size of the non-conductive sphere in the second and fourth steps
Is smaller than the desired thickness of the electroformed layer,
Take out from the solution and place more nonconductive spheres on the nonconductive spheres
Attach the body, put it in the electrolyte and apply the electroforming process again
By repeating this, an electroformed layer having a desired thickness is formed, and after forming the laminate , the laminate is separated from the model, and the remaining non-conductive spheres are removed to open a large number of pores penetrating from the front surface to the back surface. Method for producing an electroformed shell. 4. Before Symbol first step includes a step of drying by applying a primary conductive coating on the surface of the model, and applying a textured secondary conductive coating over the primary conductive coating, the secondary 4. A method for producing an electroformed shell according to claim 3, comprising the step of attaching a nonconductive spherical body before the secondary conductive paint dries.