JPS6334835B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a porous ink-impregnated body.

Conventionally, when producing a porous ink-impregnated body using synthetic rubber or synthetic resin, the following method has generally been used.

(1) Sintering method In this method, rubber or synthetic resin powder or fine particles are placed in a certain mold, and the powder or fine particles are sintered while being heated under pressure. This method forms fine continuous pores in between.

However, this method has the following drawbacks. In other words, it is difficult to control the quality of the raw material powders and fine particles.

Difficult to maintain molding conditions to produce products of constant quality.

Sintering and forming takes time and is uneconomical.

The product lacks strength.

(2) Vulcanization method This method is a method in which a substance that dissolves in water is mixed into raw material rubber, etc., and after vulcanization, this dissolved substance is eluted to form fine continuous pores. However, this method has the following drawbacks.

It takes time and effort to mix water-soluble substances into raw rubber in advance.

In the above-mentioned mixing process, a high degree of skill is required to uniformly mix the water-soluble substances throughout.

In addition, even if the mixture is uniformly mixed in the above-mentioned mixing process, when using metal salts such as sodium chloride and barium chloride among water-soluble substances, elution after vulcanization is easier than other water-soluble substances. Although the crystal shape of the metal salt is the same as the shape of the pores, the contact state between the crystals of each metal salt remains at point contact or extremely narrow surface contact, resulting in poor connectivity after elution.

Therefore, an object of the present invention is to provide a method for manufacturing a porous ink-impregnated body that eliminates the above-mentioned drawbacks.

Hereinafter, the content of the present invention will be explained in detail.

First, a manufacturing method, which is one aspect of the present invention, will be explained.

In the drawings, FIG. 1 shows the basic structure of the equipment of the present invention.

A shows the upper mold.

The illustrated upper mold A has an inverted T-shape and has a press-fitting part a, but it is not limited to this.

The material can be freely selected depending on the material to be molded, but it is generally preferable to use metal, especially carbon steel.

B is the lower mold.

This lower mold B has a hollow b on the inside, and a suitable recess 1 is formed in the inner bottom surface as required. This recess 1 is formed by engraving characters, patterns, etc. that are desired to be formed on the ink-impregnated body.
2 is an air vent hole.

These air vent holes 2 are formed at appropriate locations on the lower mold B. In the case shown in the figure, there are three air vent holes on the bottom surface.
Two are formed on each side wall. If it is formed on the bottom surface, it may be formed at the position shown in the figure, or at the recessed portion 1.
It may be formed inside.

The material of the lower mold B may be freely selected depending on the material to be molded, but it is generally preferable to use metal, particularly carbon steel.

The outer dimensions of the press-fitting part a of the upper mold A are almost the same as the inner diameter dimensions of the hollow part b of the lower mold B, and the head part a of the upper mold A
is fitted into the hollow part b of the lower mold B so as to be vertically movable.

Next, FIG. 2 will be explained.

FIG. 2 is an explanatory diagram of the case where a porous ink-impregnated body is manufactured using the basic structure shown in FIG. 1.

FIG. 2A shows a state in which the lower mold B contains an appropriate amount of particles of a soluble substance, such as salt C.

The particle size of the stored salt C is 1 mm or less, preferably between 10 microns and 300 microns.

Next, Figure B shows an enlarged view of the state in which the salt particles C in the state shown in Figure 1 are heated to around 800 degrees, the point contact is changed to surface contact, and the salt particles are sintered. It is shown as follows. Most of the salt particles before sintering are cubic and each particle is angular, so the gaps caused by contact between the particles are angular and do not form the smooth gaps 10 as shown in Figure B.

Gaps 10 are formed between the sintered salt particles C so that they communicate with each other. The size of this gap 10 varies depending on the size of the soluble substance used, but is approximately 5 microns to 400 microns.

Next, Figure C shows the lower mold B in the state shown in Figure 2.
The state in which the molten metal D is poured into the mold and then pressed with the upper die A is clearly shown.

In the following, a case will be described in which a porous ink-impregnated body is manufactured using various molten metals.

(1) When rubber is used as a raw material (including liquid rubber) Synthetic rubber or natural rubber is made into a thin plate, or
Or, after making it into a thin rod, process it into granules,
In addition, methyl ethyl ketone or toluene, etc.
It is dissolved in a solvent suitable for dissolving rubber, liquefied, and used as molten metal. When using liquid rubber, the liquid rubber is used directly as a molten metal.

This molten metal is poured into the lower mold B, degassed if necessary, the upper mold A is press-fitted into the lower mold B, and the molten metal D is gradually poured into the gap 10 communicating between the sintered salt C. Infiltrate. This state is illustrated in FIG. 2C.

If necessary, remove air from the air vent hole 2 of the lower mold B to reduce the pressure inside the lower mold B and release the molten metal D.
helps infiltration.

Once the molten metal D has penetrated into the gaps 10 of the salt C, the solvent is evaporated and only the raw rubber remains in the gaps 10 to produce an ink-impregnated material. FIG. 2E shows this state in an enlarged manner.

Next, the raw rubber D' in the gaps 10 of the sintered salt is vulcanized by heating the upper mold A and the lower mold B in the state shown in FIG. 2D, thereby producing an ink-impregnated body material.

The vulcanization temperature is from 100 degrees to 200 degrees, and the time is
The duration is 15 to 30 minutes.

After vulcanization, the ink-impregnated body material is placed in the upper mold A.
and the lower mold B without separating them, or as shown in Figure 2 D, or by separating the upper mold A from the lower mold B and removing the lower mold B.
Then, remove the ink-impregnated body material and place it in hot water (20 to 60 degrees) to dissolve the salt.
The ink-impregnated material after the salt C has been eluted in this manner is shown as an enlarged view in FIG.

As shown in the figure, the raw rubber D' is vulcanized and bonded together, while the salt C is eluted and a space is formed there. The spaces communicate with each other to form ink flow holes 11, thereby forming a porous ink-impregnated body made of rubber and having these ink flow holes 11 formed throughout.

In addition, as shown in Fig. 1, on the bottom surface of the lower mold B,
When a recess 1 consisting of letters, patterns, etc. is formed, salt and molten metal D are also applied to the recess 1.
The convex portions corresponding to the concave portions 1 are also integrally formed on the surface of the porous ink-impregnated body.

Therefore, in this case, the porous ink-impregnated body E has convex character portions 12 formed on its surface, as shown in FIG.

The user impregnates this printed body with ink, and when using it as a hand stamp, stores it in a suitable grip and uses it for stamping.

The above explanation is for manufacturing printing bodies, but the same process can also be used when manufacturing rollers, stamping bodies for stamp holders, and pen cores for writing instruments. It is possible to use a method.

(2) When thermoplastic synthetic resin is used Even when thermoplastic synthetic resin is used, the porous ink-impregnated body is basically manufactured by the method described in (1) above.

However, in this case, the following points need to be kept in mind.

In other words, since the raw material is a thermoplastic synthetic resin,
In order to turn this into a molten metal, the raw material must be heated to the melting temperature of the raw material resin. If necessary, a plasticizer may be used in combination with heating, or a solvent may be used in combination. The molten metal used here is infiltrated into the gap 10 of the sintered salt C shown in FIG. In order to combine them to form an ink-impregnated body material, it is only necessary to recover the added plasticizer or solvent and cool the molten metal D.

Thereafter, the salt is eluted by washing with water to create continuous gaps, which are then impregnated with ink and used for various purposes.

As the thermoplastic synthetic resin used here, basically any synthetic resin having plasticity may be used, but in particular, polyacetal resin, propylene resin, polyethylene resin, etc. are used.

Even when using this method, in order to form characters, patterns, etc. on the surface of the ink-impregnated body material made of thermoplastic synthetic resin, it is necessary to form recesses on the bottom surface of the lower mold B or the lower surface of the upper mold A. Correspondingly, letters, patterns, etc. are formed on the surface of the ink-impregnated material. The same manufacturing method is used when manufacturing rollers, when manufacturing stamp pads for stamp holders, when manufacturing pen cores for writing instruments, etc.

(3) When thermosetting resin is used as a raw material When thermosetting resin is used as a raw material,
Both are used in an initial condensed state.

If necessary, use a hardening agent.

The raw materials used include phenol resin, melamine resin, and polyester resin.

Hereinafter, a case where a phenolic resin is used will be explained.

First, a curing agent is added to an initial condensate of a phenolic resin as necessary to form a molten metal.

This is poured into the lower mold B in the state shown in FIG. 2A, and is allowed to penetrate into the gaps 10 formed between the particles of sintered salt C.

In this case, the upper die A is pressed from above and the molten metal 1
0 infiltration, and lower mold B if necessary.
The air is removed from the air vent hole 2, and the molten metal D reaches the gap 10.
It helps them penetrate into the world.

Next, after defoaming the air contained in this molten metal D, both the upper mold and the lower mold are heated to cause reaction hardening.

Subsequently, the salt is washed out with water to form an ink-impregnated material made of phenolic resin.
This is impregnated with ink and used as a porous ink-impregnated body.

Whether this is when manufacturing rollers,
Whether it is manufacturing a stamp body for a stamp pad,
Exactly the same manufacturing method is used when manufacturing pen refills for writing instruments.

The porous ink-impregnated body formed by the manufacturing method explained above has characters, patterns, etc. formed in advance on the upper mold or the lower mold as described above, and then the ink-impregnated body material is formed and the characters are added to the surface of the porous ink-impregnated body. Alternatively, when forming an ink-impregnated body material by the above method, a flat ink-impregnated body material is formed, and then, if necessary, letters and patterns are carved on the surface using an engraving machine etc. It is also good to use a method of engraving etc.

As described above, the present invention involves infiltrating the raw material in the molten state into the gaps formed between the salt particles in the sintered state, heating or cooling as necessary, and then washing out the salt to form countless fine particles. A porous ink-impregnated material is formed by forming an ink-impregnated material with continuous pores, and impregnating it with ink to create a porous ink-impregnated material.
Each salt particle is in surface contact. In other words, when it becomes a porous ink-impregnated body, the salt particles form countless fine continuous pores, so compared to conventional manufacturing methods, the manufacturing process is simpler and mass production is possible in a short time. In addition, since the salt is uniformly dispersed, there is an advantage that a porous ink-impregnated body having a certain quality can be obtained.

Furthermore, the porosity can be arbitrarily selected between 30 and 90% by adjusting the degree of sintering of the salt, and the pore size and shape can also be changed freely by simply selecting the particle size of the salt. There are advantages.

Furthermore, the produced porous ink-impregnated body has strength and is optimal for use as printed bodies, rollers, type bodies, pen cores, etc.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an upper mold and a lower mold. FIG. 2A is a diagram showing the state in which salt is poured into the lower mold. Figure 2B is a cross-sectional view of sintered salt. FIG. 2C, D, H, and F are explanatory diagrams showing the molding state. FIG. 2 is a perspective view showing the manufactured printed body.

Claims (1)

[Claims] 1 Place salt in the lower mold, heat and sinter the salt to form gaps between the salt particles,
Molten rubber or synthetic resin is introduced into the gaps of the above-mentioned common salt, and the rubber or synthetic resin is solidified by cooling or heating, and then the salt flows out to form a porous ink impregnation having countless fine continuous pores. How to manufacture the body.