JPS595113B2 - Printing belt for rotating stamps - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink-absorbing printing belt mainly used for rotary stamps.

In recent years, with the spread of stamping devices such as recognition stamps that are capable of continuous stamping using porous stamp materials having ink-absorbing properties, there has been a demand for rotary stamps that are capable of continuous stamping in this manner.

For example, as shown in FIG. 5, an ink storage part b (open cell) is combined with a binding band a, and a printing part C (sintered foam of thermoplastic resin powder) is formed on the ink storage part by heat. A fused printed bell) d has been proposed.

However, in such a structure, if the ink occlusion section and the coupling band C are insufficiently bonded, there is a problem that the two may separate when the printing belt d is rotated and bent.

The present invention has been made in view of the above, and its main object is to provide a printing belt for rotating stamps which has improved strength and is free from the risk of the printing part or ink storage part falling off due to rotational bending. .

First, the present invention will be described with reference to FIG. 1 with regard to one embodiment. A printing belt 1 is constructed by heat-sealing porous ink storage portions 3 on a belt-shaped reinforcing woven fabric 2 at predetermined intervals. The printing portion 5 of the surface portion 7 is integrally molded in such a manner that a porous printing portion 5 having a character portion 4 is connected to the ink storage portion 3 by a connecting portion 6, and corresponds to the ink storage portion 3. 3, the printing part 5 and the ink storage part 3 are heat-sealed so that their pores are connected, while the connecting part 6 is heat-sealed on the reinforcing fabric 2 at high temperature and pressure, The porosity of the ink storage section 3 is set to be larger than the porosity of the printing section 5.

Reference numeral 8 denotes a protrusion in the width direction, which protrudes from the back side of the connecting portion 6.

This protrusion 8 ensures that the printing belt 1 rotates reliably when attached to the rotary stamp, and also prevents the printing surface from changing due to the rotation of the printing belt 1 during stamping.

To explain the above embodiment in more detail, the surface portion 7 is made of thermoplastic resin powder and thermoplastic resin porous powder including porous fine powder obtained by crushing a gelled or semi-gelled polyvinyl chloride resin porous body. It is formed by thermally fusing (sintering in the printing part 5) powder obtained by crushing a mass.

Examples of thermoplastic resins include those having rubber-like elasticity, such as polyvinyl chloride resin, ethylene-vinyl acetate copolymer (E
VA), thermoplastic polyester elastomer, thermoplastic polyurethane elastomer, etc. are used.

The ink storage part 3 is made of a material that can form a porous elastic body (sintered foam) with a continuous pore structure that has an excellent ink storage and replenishment mechanism. It is made of resin material powder and can be integrated with the printing part 5.

For example, polyvinyl chloride resin, EvA, synthetic rubber, polyurethane, polyester, etc. are used.

In order to smoothly supply ink to the printing part 5 and the ink storage part 3, the porosity of the printing part 5 (ratio of pores to the total volume) is 40 to 60% (expressed in density). 0.
5 to 0.7 y/cfIl), and the porosity of the ink storage section 3 is 60 to 80 inches (expressed in density, 0.3 to 0.45
? /crtl, and the ink storage section 3 is the printing section 5.
The porosity is set to be a factor of 10 or more larger than the porosity.

Natural and synthetic fibers are used for the reinforcing woven fabric 2, but
In particular, it is desirable that the expansion/contraction rate is small and that the material is not affected by the environment.

For example, a monofilament warp made of fibers such as polyester, nylon, or tetron for strength,
A material woven with multifilament weft yarns is used from the viewpoint of the ink tracking effect, and has sufficient strength.

Hereinafter, the configuration of the present invention will be specifically described with reference to embodiments.

Polyvinyl chloride (paste resin) 100 parts by weight DOP
40BBP
30DOA
5 Surfactant (
A mixture of 10 parts (bubble stabilizer) and 2 parts stabilizer is mixed and stirred to prepare a plastisol, and a gas such as air is mixed and dispersed in the plastisol using an open cell machine to mechanically foam the plastisol.

This foam is poured into a mold of 2 to 10 m and m thick, and molded.
After molding, heat in an open air at 125 to 165°C for about 5 to 30 minutes to gel or semi-gel, remove from the oven in this gel or semi-gel state, cool to room temperature, and then remove from the mold. Make a mold.

The foam thus obtained has an interconnected cell structure and a uniform fine cell structure, and has brittle physical properties that can be easily pulverized because it is gelatinized or semi-gelled.

Subsequently, the above-mentioned gelled or semi-gelled foam is pulverized physically or by a freezing pulverizer, and then passed through a sieve having a particle size of 40 mesh or less (preferably 200 mesh or less).

The powder thus obtained is a porous powder and is used in the present invention.

The foam obtained in this example has a density of 0.390 (iP
/c already has pores with a pore diameter of 10 to 100 μm, but the density and pore size may vary depending on the type of thermoplastic resin, plasticizer, type of surfactant, or a combination of these, or the amount of air mixed in. Pore diameter etc. can be changed.

Next, the obtained powder is filled in the recesses (not shown) of the new model for stamping molding as described above, and a rubber letterpress previously prepared by the new model or by another means is fitted into the recesses. Then, heat and pressure was applied uniformly over the entire surface for about 3 minutes at a pressure of 50°C and a temperature of 175°C to form a plate surface portion 11 with a substantially uniform thickness as shown in FIG. do.

In this state, the plate surface portion 11 has a portion 12 that will become the printed portion.
The connecting part 13 is also porous. 8 Among the recesses of the above-mounted type, the character recess has a depth of 1.5 mm and a shoulder angle (the angle between the bottom surface and the side surface of the character recess) of 105 degrees. The one formed in is used.

Next, as shown in Figure 3, a new type of recess (not shown) was installed.
The same powder 15 as that used to form the plate surface part 11 is filled into the hollow space 14 of the plate surface part 11 placed inside, the reinforcing fabric 2 is placed on top of it, and the reinforcing fabric 2 is placed on top of it. The powder 15 is piled up and molds 16 and 17 are applied.

In this case, more powder 15 is piled up near the portion 13 that will become the connecting portion than near the portion 12 that will be the printed portion, and is buried inside the reinforcing fabric 2.

The material of the molds 16 and 17 is AL 545, respectively.
C or 555C, which are different.

17a is a recess formed in the mold 17 corresponding to the protrusion 8.

After that, the condition shown in Fig. 3 was heated to 200% pressure.
Heat and pressurize again for about 6 minutes at a temperature of 175°C.
Set it to the state shown in the figure.

That is, the vicinity of the portion 12 that will become the printed portion is at almost the same temperature (sintering temperature) and pressure as the first heating and pressurization described above, and the vicinity of the portion 13 that will be the connecting portion is the vicinity of the portion 12 that will be the printed portion. Pressurize and heat at higher temperatures and pressures.

Note that the pressure difference as described above is caused by the difference in the amount of compression of the powder 15.

For example, the distance around the part 13 that becomes the connecting part is 5? #l is compressed to a thickness of about 0.6 mm.

In addition, the temperature difference is due to the difference in the materials of the molds 16 and 17.
This is caused by the difference in the amount of heat given to the powder.

Furthermore, although the temperature is the same in the first and second heating, the heating time is different, so the amount of heat given to the powder is different.

That is, the second time is larger. In this way, the printing belt 1 shown in FIG. 1 is obtained.

In this printing belt 1, the printing part 5 of the surface part 6 remains porous and contains the ink storage part 3 (sintered foam) inside, but the connecting part 6 has the pores crushed and becomes non-porous. As a result, the strength is increased, and it is strongly heat-sealed to the reinforcing fabric 2.

As described above, the printing part including the ink storage part and the connecting part are integrally molded, and the connecting part of the surface part is thermally fused to the reinforcing fabric. The cloth has an excellent effect in that it is strongly bonded and there is no fear that the printed part (surface part) will peel off.

[Brief explanation of the drawing]

1 to 3 illustrate embodiments of the present invention, FIG. 1 is a cross-sectional view of a printing belt for a rotating stamp, FIG. 2 is a cross-sectional view of a surface portion, and FIGS. 3 and 4 are a rotating FIG. 5 is a cross-sectional view showing the state before and after forming a stamp printing belt, and FIG. 5 is a side view of a conventional rotary stamp printing belt. 1...Printed belt, 2...Reinforced woven fabric,
3... Ink storage section, 4... Type section,
5... Printing section, 6... Connecting section, 7...
...Surface part.

Claims (1)

[Scope of Claims] 1. A plurality of porous ink storage portions are heat-sealed at predetermined intervals on a reinforcing woven fabric in the form of a belt, and the porous material corresponds to the porous ink storage portions and has a printed character portion. The porous printing portion of the surface portion, which is formed integrally with the printing portions connected at the connecting portion, contains the ink storage portion so that the pores of the porous printing portion and the ink storage portion communicate with each other. The rotary stamp is characterized in that the connecting portion is heat-fused onto the reinforcing fabric at high temperature and pressure, and the ink storage portion has a larger porosity than the printing portion. printing belt. 2 The porosity of the printing part is 40 to 60%, while the porosity of the ink storage part is 60 to 80, which is 10% lower than that of the printing part.
A rotary stamp printing belt according to claim 1, which is larger than the above. 3. The rotary stamp printing belt according to claim 1, wherein the connecting portion has a protrusion on the back side. 4. The printing belt for rotary stamps according to claim 1, wherein the reinforcing woven fabric is a synthetic fiber woven with monofilament warp threads and multifilament weft threads.