JPH0367680A - Manufacture of fine ceramic seal - Google Patents

Abstract

PURPOSE:To allow the style of a character formed in calcining process to be deformed due to non-uniform contraction and distortion and a different style of character for each sintered piece by forming a character in a molded product in a stage preceding the calcining process of a fine ceramic which is a raw material for a seal. CONSTITUTION:For raw material preparation, binder, dispersant, lubricant and other ingredients are blended as raw material powder and additives to that physical and mechanical properties required for the manufacture of a fine ceramic chop as a finished product. This raw material powder is molded in a specified shape. That is, a molded product for the seal body is obtained using any appropriate molding technique such as cast molding. Next, a character 3 is carved on the surface in molded product processing. This seal body 1 is baked in a furnace according to a specified calcining pattern. During this calcining process, the chop body 1 which is a mixed molded product develops a non- uniform contraction and distortion in its every part and as a result, the character of the molded product 1 is deformed into a style. After this, the chop undergoes a finishing process and a fine ceramic chop is obtained as a final product.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for manufacturing a seal, and more particularly, to a method for manufacturing a fine ceramic seal in which a seal with the same printed font is not duplicated. .

(Conventional technology) Seals are used for various certifications and approvals.

A registered seal is especially important, and it is desirable that the impression cannot be easily duplicated, so it is usually manufactured by hand carving. In other words, in general, registered seals are manufactured by processing materials obtained from plants and animals in the natural world, such as wood, ivory, and rhododendron, into a certain shape, and then inscribing them by hand. There is.

(Problems to be Solved by the Invention) Since such hand carving has poor production efficiency, it is conceivable to adopt machine carving. However, if machine engraving is used, many identical seals will be created.
Not suitable for manufacturing registered seals.

On the other hand, in recent years, it has become difficult to obtain ivory, which is popular as a high-quality material for seals, and there is a growing demand for alternative materials.

In view of this point, it is an object of the present invention to propose a new method for manufacturing a seal stamp, which does not use stamp materials that have been commonly used in the past, and which is extremely difficult to duplicate.

(Means for solving the problem) In order to solve the above problem, the inventors of the present application, etc.
Focusing on the fact that fine ceramics, which have been used in various applications in recent years, have sufficient strength, we will utilize this fine ceramic as a material for seals, as well as improve the uneven shrinkage of this fine ceramic during firing. Focusing on the non-uniform distortion characteristics, we devised a method for manufacturing seals that are difficult to reproduce by actively utilizing this shrinkage.

That is, the present invention includes a step of preparing a ceramic powder raw material, a step of mixing the prepared powder raw material and an additive, a molding step of molding the mixed powder raw material into the shape of a seal body, and this molding step. A molded body processing step in which characters are engraved on the molded body of the seal body formed through the process, and a firing process in which the molded body of the stamp body that has been engraved is fired.
We are now manufacturing seals made of fine ceramics. Here, instead of performing the inscription in the molded body processing step described above, such a processing step may be omitted and the inscription may be formed simultaneously in the stamp body forming step.

<Function> As described above, in the seal manufacturing method of the present invention, fine ceramics are used as the stamp material, and the inscription is performed at a stage before firing the ceramic molded rod.

Therefore, even if the same stamp is machine-engraved on each ceramic molded body at this stage, the molded body will exhibit uneven shrinkage and distortion characteristics during the firing process, so the fine ceramic stamp obtained after firing will , each with a different seal impression.

In this manner, the method of the present invention is suitable as a method for manufacturing seals such as registered seals, since seals with the same seal impression are not reproduced. In addition to this, seals of various colors can also be manufactured by appropriately selecting ceramic raw materials.

(Example) The present invention will be described in detail below with reference to FIGS. 1 to 3.

FIG. 1 shows a flowchart of the method of the invention. As shown in this figure, the seal manufacturing method of the present invention can utilize a general fine ceramic sintered body manufacturing method as is. That is, first, in raw material preparation step A, raw material powder and additives such as binders, dispersants, and
Prepare lubricants, etc. As the raw material powder, att.

3, ZrO, SiC, TiNsSiAlON, silicon nitride, etc. can be used Next, in the mixing step B, these raw materials are uniformly mixed to form a mixed powder.

In the molding step C, the mixed powder is molded into a certain shape. In other words, select an appropriate molding method from cast molding, extrusion molding, press molding, injection molding, etc. to form the molded body of the seal body. do. In addition, when a press molding method is adopted, as shown in the figure, the press surface pressure is set to, for example, 1 to 1.5 tons/d.

In the next molded body processing step, characters are engraved on the surface of the molded body of the stamp body obtained through this molding process. As shown in FIG. 2, when the stamp body 1 is cylindrical, a font 3, for example "Hojo", is carved on the end face 2 by machine engraving using a carbide tool. Thereafter, in a firing step E, this stamp body 1 is fired in a furnace under a certain firing pattern. During this firing, the stamp body 1, which is a ceramic molded body, undergoes uneven shrinkage and distortion in each part, and as a result, the font of the molded rod 1 shown in FIG. 2 changes from the font shown in FIG. 3. Transforms into 4. After this, a final product, a fine ceramic seal, is obtained through a finishing process.

Table 1 shows general firing patterns in the above firing process for typical raw materials.

(Table 1) TiN firing pattern 5°C/peak 10°C/-t-2h 11
0°C/, i.

OoC--→900"C-1→1700℃+1700
'C--→0°C3iCOoC-1→1ooO℃--→
215oC--→2150''C-1→S p 5°C/si, I 10'C/, i,
lh 110°C/1
15.

0°C-1→1O00°C--→1850"C-1→1
850"C-1 → O'CAt, os (92, Atzoi (ants) 2, 0°2°C/-+112h 5°C/-t-60
0'C--1→1600℃-+ 1600℃-11→2
°C/, i, 2h 5 °C/, i
.

600"C---1→1650'C---→1650'C
-11→1℃/15, 1h
2℃/ll1n600"C-+ 1500℃-11→1500"C-11→Here, in the above example,
Although the font is formed on the molding rod 1 by machine shaping, instead of this, the font part is formed in the mold or press die used in the molding process, and the font part is formed at the same time as the bottom shape. The font may also be formed accordingly.

In addition, when TiN is used as a raw material for ceramics, it is possible to obtain a gold-colored and luxurious seal, and S
By selecting raw materials, for example, black when using iC and white when using ZrO,
Seals of various colors can be manufactured.

(Effects of the Invention) As explained above, in the seal manufacturing method of the present invention, fine ceramics are used as the material for the seal, and fonts are formed on the molded rod at a stage before firing the fine ceramics. Therefore, according to the method of the present invention, the font formed in the firing process shrinks and distorts non-uniformly and is deformed, so it is difficult to manufacture seals with different fonts for each individual sintered body. I can do it.

Another advantage is that seals of various colors can be manufactured by appropriately selecting raw materials.

[Brief explanation of drawings]

Fig. 1 is a flowchart showing an example of the manufacturing process of the present invention, Fig. 2 is a perspective view showing the font formed on the molded rod before the firing process in Fig. 1, and Fig. 3 is the baking process in Fig. 1. FIG. Explanation of symbols A... Raw material preparation process B... Mixing process C... - Molding process D... Molded body processing process E - Firing process 3 - Before firing Font 4 - - After baking font.

Claims (2)

[Claims] (1) A step of preparing a powder raw material for ceramics, a step of mixing the prepared powder raw material and an additive, a molding step of molding the mixed powder raw material into the shape of a seal body,
A method for manufacturing a fine ceramic seal stamp, which comprises a molded body processing step of inscribing characters on the molded body of the stamp body formed through this molding step, and a firing step of firing the molded body of the stamp body that has been engraved. (2) The method for manufacturing a fine ceramic seal according to claim 1, wherein inscriptions are simultaneously formed in the molding step instead of the molded body processing step.