JPS5810468B2 - chemical engraving method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chemical engraving method that allows precise and deep engraving.

As is well known, the chemical engraving method involves masking the necessary parts of the metal object by various methods such as photomask method and taping method, and then etching the exposed parts with corrosive solution. There is.

In the engraving method described above, since the corrosive liquid contacts the surface to be processed only once, the pattern formed by corroding the metal body is shallow.

When the corrosive solution is repeatedly applied to form deep irregularities,
As shown in FIG. 6, side etching, that is, etching progresses not only in the depth direction of the metal body 9 but also in the lateral direction, and the mask 8
The width of the corrosion hole 91 is larger than the opening width of.

In addition, it is not possible to control the etching depth in such a way that some parts of the surface to be processed are etched shallowly and some parts are etched deeply, so as shown in FIG. is impossible to form.

For prevention of side etch, Kirin blood method or powderless method can be adopted.

However, Kirin blood resin powder must be fused to the side wall of the corrosion hole each time it is etched, and this operation must be repeated until the corrosion hole reaches the desired depth, which is extremely time consuming and impractical.

Furthermore, the powderless method uses an etchant containing a special additive, and has various limitations such as the method of applying the etchant and the need to face down the surface of the metal body to be machined, which limits its scope of application.

Further, even with the above-mentioned sideways method, masking of the metal body and removal of the mask are indispensable and time-consuming.

In view of the above-mentioned circumstances, the present invention provides a chemical engraving method that can easily and inexpensively form a precise and deep uneven pattern using a matrix.

The present invention will be specifically described below based on embodiments shown in the drawings.

FIG. 1 shows a matrix 1 used in the present invention, which is formed into a cylindrical shape from a material that is not affected by etching solution, such as vinyl chloride or epoxy resin, and has an uneven pattern 2 on its outer circumferential surface. There is.

When the uneven pattern 2 of this embodiment is developed, it becomes a world map as shown in FIG. 2, in which the sea, plains, and mountains are precisely represented by unevenness.

Hydrophilic treatment is performed using, for example, a solution of potassium dichromate, sulfuric acid, and water mixed in appropriate proportions so that the surface of the mother mold is uniformly wetted with the corrosive solution.

FIG. 3 shows a metal body 3 to be machined, the diameter of which is approximately equal to the maximum diameter of the matrix 1, and its total length equal to the total length of the matrix 1.

The surface of the metal body 3 is subjected to activation treatment such as degreasing. Figure 4 shows the processing method. The mother mold 1 is placed so that it can rotate freely so that the lower part thereof is immersed in the corrosive liquid.

A support shaft 32 is fitted into the through hole 31 of the metal body 3, and a biasing means (not shown) such as a spring is connected to the shaft 32 to bias the support shaft 32 and therefore the metal body 3 toward the mother mold 1. , metal body 3
is brought into contact with the mother mold 1.

In the above state, either the mother mold 1 and the metal body 3 are brought down, or both are connected to a rotary drive device (not shown) and rotated at low speed in opposite directions.

The frictional rotation of the matrix 1 and the metal body 3 which are in contact with each other causes the corrosive liquid to be applied to the metal body 3 via the matrix 1 by forced rotation.

Since this application is performed by contact between the protrusions on the surface of the matrix 1 and the metal body 3, the amount of corrosive solution applied at one time is small when the part of the metal body 3 that is in contact with the protrusions of the matrix is corroded. Therefore, the amount of corrosion of the metal body 3 is minute.

However, as the matrix 1 continues to rotate, the corrosive liquid is repeatedly applied to the metal body 3 by the convex portions of the matrix 1, and eventually the three-dimensional irregularities are opposite to the irregularities pattern 2 of the matrix 1. Patterns can be formed.

Experiments have shown that it is possible to engrave at a depth of 40 microns per hour.

During the above-mentioned engraving process, rust forms on the surface of the metal body 3, but the convex part of the matrix 1 copies the rust, or the convex part presses against it, causing cracks in the rust film, and the rust on the surface of the metal body 3. It prevents thick build-up and does not interfere with the application of corrosive solution.

However, if the surface of the metal body 3 is periodically rubbed with a brush or the like to remove rust, the effect of applying the corrosive liquid will be enhanced and the engraving speed will of course be increased.

FIG. 5 shows a method of engraving a plate-shaped metal body 3 using a plate-shaped master mold 1.

The mother mold 1 is fixed on a table 6, and an etchant is applied to the mother mold 1 by a coating roller 5 that rolls on the mother mold 1.

A supply roller I whose lower part is immersed in a corrosive liquid tank 4 is provided at one end of the table 6. When the coating roller 5 reaches the moving end, it comes into contact with the supply roller 7, and the rotation of the supply roller 7 causes the corrosive liquid to flow out. It is supplied to the application roller 5.

An elevating frame 61 is provided above the transfer path of the application roller 5, and the metal body 3 is attached to the punching frame 61.

Each time the coating roller 5 makes one reciprocation, the metal body 3 attached to the lifting frame 61 descends and comes into contact with the matrix 1, and as before, the corrosive liquid is repeatedly applied to the metal body 3 via the matrix 1, thereby removing the metal. A deep uneven pattern can be formed on the body 3.

FIG. 8 shows a method of engraving a metal body 3 whose entire surface to be processed is largely concave.

The processed surface 33 of the metal body 3 is recessed into a bowl shape at the same time as the metal body 3 is cast, or by pre-processing such as cutting.

The mother die 1 is bulged to correspond to the large depression on the surface 33 to be processed of the metal body 3, and an uneven pattern 2 with a vertical slope is formed on the surface of the bulge 1a.

An etchant is intermittently applied to the matrix 1 by the spray device 40, and the matrix 1 and the metal body 3 are repeatedly brought into contact as described above to engrave the processed surface 33 of the metal body 3.

Of course, the method of applying the corrosive liquid to the matrix using the spray device described above can also be applied to the cylindrical matrix 1 shown in FIG. 4 or the plate-shaped matrix 1 shown in FIG. be.

FIG. 9 shows an embodiment in which a cylindrical master mold 1 is rolled against a plate-shaped metal body 3 fixed on a table 6 to engrave the metal body 3. FIG.

The mother die 1 is placed on a moving frame 62 together with a plurality of application rollers 5 and a tank 4 containing an etchant, and the moving frame or table 3 is connected to a reciprocating device (not shown), so that the moving frame and the table 3 are moved relative to each other. move in a specific manner.

Further, the moving frame 62 or the table 6 can be moved by a suitable means such as a spring.
One of them is biased against the other to move the moving frame 62 and thus the matrix 1 and the metal body 3 closer together in accordance with the engraving depth of the metal body 3.

The master mold 1 coated with the corrosive liquid via the coating roller 5 repeatedly rolls on the metal body 3 to engrave deep irregularities on the metal body 3.

As described above, the present invention provides a matrix 1 having an uneven pattern formed on its surface.
Since the corrosive liquid is repeatedly applied to the metal body 3 through the etching process, a deep uneven pattern can be easily formed on the metal body 3, contrary to the unevenness of the matrix 1.

In addition, there is no need to apply or remove masking as in the conventional method, and since no masking is used, there is no risk of side etching, and it has the excellent effect of forming a precise uneven pattern that is faithful to the mother mold. has.

[Brief explanation of the drawing]

Figure 1 is a perspective view of the matrix, Figure 2 is a developed view of the surface of the matrix, Figure 3 is a perspective view of the metal body, Figure 4 is an explanatory diagram of the engraving device, and Figure 5 is another example. 6 is a sectional view of side etching, FIG. 7 is a sectional view of a stepped groove formed in a metal body, and FIG. 8 is another embodiment in which the entire surface to be machined is greatly concave. The sectional view shown in FIG. 9 is an explanatory diagram of another embodiment in which a plate-shaped metal plate is engraved using a cylindrical master mold. 1...Mother mold, 3...Metal body, 5...Applying roller.

Claims (1)

[Scope of Claims] 1. A corrosive liquid is applied to a mother mold made of a corrosion-resistant material and has an uneven pattern on the surface, and the corrosive liquid adheres to the convex portions of the mother mold by bringing the mother mold into contact with a metal body. By shallowly corroding the metal body, and repeating the application of corrosive liquid to the matrix and the contact between the protrusions of the matrix and the metal body, the depth of corrosion of the metal body is increased and the uneven pattern of the matrix is changed. A chemical engraving method that is characterized by forming an uneven pattern in which the unevenness is reversed. 2. The matrix and the metal body are cylindrical, and are rotatably supported in contact with each other, and the corrosive liquid is transferred from the matrix to the metal body while rotating in opposite directions. chemical engraving method. 3. The chemical engraving method according to claim 1, wherein the matrix and the metal body are plate-shaped, and the matrix and the metal body are brought into contact and separated repeatedly to transfer the corrosive liquid from the matrix to the metal body.