JP2002361992A - Seal and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seal capable of obtaining a sharp print of the seal, generating no offensive smell or the like at the time of processing and capable of well obtaining the face-of-seal state after processing, and a method for manufacturing the same. SOLUTION: The seal is obtained by subjecting a porous flat plate to laser processing and has a carved surface wherein pores not heat-sealed to the laser irradiated surface are present. The seal is manufactured by impregnating the porous flat plate with a liquid substance and carving the porous surface of the porous flat plate by laser irradiation to form unevenness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stamp formed by laser processing and a method for producing the stamp. More particularly, the present invention relates to a stamp which contains ink beforehand and enables continuous stamping without the need for a stamp table or a vermilion table. The present invention relates to a penetrating stamp and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, when a stamp is manufactured by laser processing, a cross-linked rubber such as acrylonitrile-butadiene copolymer rubber or ethylene-propylene-diene copolymer rubber has been used as a porous flat plate. These crosslinked rubbers can form very good stamp engravings by laser processing, but generate an unpleasant odor during processing and require a large-scale device for exhausting, which makes handling inconvenient. It was something. In addition, after processing, scum adhered to the stamp, requiring cleaning. Further, a silicone rubber having a silicone base material which does not easily generate an offensive odor has been proposed and put to practical use, but it was very expensive. Furthermore, when trying to engrave a stamp by laser processing of a thermoplastic porous body as it is, the heat of the melted part propagates to the periphery, and the shoulder of the character hangs down due to this heat, and a sharp impression is obtained. Because it was impossible, it has not been put to practical use.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems and demands in the prior art, and provides a sharp imprint, no odor or the like during processing,
Further, it is another object of the present invention to provide a stamp in which a stamped surface condition after processing is well obtained and a manufacturing method thereof.

[0004]

Means for Solving the Problems The present inventor has conducted intensive studies in order to solve the above-mentioned problems. As a result, when manufacturing a stamp by laser processing, water or the like was previously applied to a porous flat plate as a material of the stamp. When laser processing is performed by including a liquid substance, a sharp imprint state can be obtained, and when the porous flat plate is mainly made of a thermoplastic material, the stamped surface state in the laser processing is improved, Further, the present inventors have found that by suppressing a sulfur-based vulcanizing agent, that is, a rubber vulcanizing agent, in the porous flat plate to a predetermined amount, it is possible to minimize the generation of an unpleasant odor at the time of processing.

That is, a stamp and a method of manufacturing the stamp according to the present invention are characterized by comprising the following constitutions or means (1) to (6), and solve the above problems. (1) An engraving characterized in that the surface of the porous flat plate is a laser-processed stamp, and the laser-irradiated surface has an engraved surface having holes that are not heat-sealed.

(2) The stamp manufacturing method according to the above (1), wherein the porous flat plate contains at least 20% by mass of a thermoplastic substance. (3) The stamp production according to the above (1) or (2), wherein the porous flat plate contains a rubber-like elastic substance, and the rubber-like elastic substance does not contain a sulfur-based vulcanizing agent. Method.

(4) This is a method for producing a stamp in which the surface of a porous flat plate is laser-processed. The porous flat plate is made to contain a liquid substance, and the laser processing is used to engrave the porous surface to form irregularities. The stamp manufacturing method according to the above (2), wherein

(5) The stamp manufacturing method according to the above (4), wherein the liquid material is water. (6) The stamp manufacturing method according to (4), wherein the liquid material is an ink.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a stamp and a method of manufacturing the stamp according to the present invention will be described below in detail with reference to the accompanying drawings. Incidentally, the stamp and the manufacturing method thereof according to the present invention are not limited to the following embodiments and examples. FIG.
1 is a perspective view showing an engraved surface of a first embodiment of a stamp according to the present invention by an optical microscope photograph. FIG. 2 is a perspective view showing the engraved surface of the second embodiment of the stamp according to the present invention by an optical microscope photograph. FIG. 3 is a perspective view showing an engraved surface of the stamp according to the third embodiment of the present invention by an optical microscope photograph. FIG. 4 is a perspective view showing an engraved surface of a first form of a stamp for comparison using an optical microscope photograph. FIG. 5 is a perspective view showing an engraved surface of a second form of a stamp for comparison by an optical microscope photograph.

[0010] The stamp according to the present invention is a stamp in which the surface of a porous flat plate is laser-processed, and has an engraved surface having holes that are not heat-sealed on the laser irradiation surface.

As shown in FIG. 1, FIG. 2 and FIG. 3, among the concave and convex surfaces of the porous flat plate of the stamp according to the present invention, the concave portions are engraved surfaces formed by laser processing. All of the holes on the engraved surface are not heat-sealed (when the engraving of the irregularities is enlarged, the holes are partially closed), that is, the engraved surface has holes that are not heat-sealed. This is achieved by including a liquid substance in the porosity of the porous flat plate during laser processing. On the other hand, when the laser processing was performed in a state where there was no liquid substance in the porous flat plate, as shown in FIG. 4 and FIG. ing. The porous flat plate shown in FIGS. 1 to 3 is a porous flat plate used under the conditions of Example 5 described later. 4 and 5 are porous flat plates used under the conditions of Comparative Example 1 described later.

As described above, when the liquid material is present or absent in the porous material during the laser processing, not only is the shape of the engraved surface of the stamp different, but also in the stamp according to the present invention, the convex portion of the porous flat plate surface is provided. Since a sufficient shoulder portion is formed and formed high (or deep), a sharp impression is obtained.
On the other hand, in a stamp manufactured without a liquid material at the time of laser processing, the hole in the engraved surface is substantially heat-sealed, and a sharp edge is not generated in the shoulder portion. In addition, the height is not sufficiently obtained, and no sharp imprint is formed.

The pore diameter of the porous flat plate is not particularly limited as long as the performance as a stamp can be maintained, but is preferably about 0.5 to 200 μm. If the thickness is less than 0.5 μm, the ejection of ink is reduced, and a satisfactory imprint density cannot be obtained. On the other hand, when the thickness exceeds 200 μm, ink ejection becomes excessive, and imprints are blurred, and drying on paper is delayed. Further, it is desirable that the porous flat plate has a thickness of 0.5 mm or more, particularly 1.0 mm or more. If the thickness is less than 0.5 mm, it is not possible to form sufficient irregularities as a stamp surface.

If the porous flat plate is made of a thermoplastic material, the imprint cannot be formed well due to the influence of heat propagation during laser processing. The stamp according to the present invention may contain a thermoplastic substance in an amount of 20% by mass or more. In the case of a porous flat plate containing 20% by mass or more of a thermoplastic substance, the influence of heat propagation at the time of processing in the porous flat plate appears,
The liquid material in the porous pores regulates the propagation of heat, and the residue generated during processing is taken into the molten thermoplastic material, so that no residual residue is generated, so that ordinary laser processing is possible.

As the above-mentioned thermoplastic substance, a thermoplastic resin or a thermoplastic elastomer can be exemplified.
As the thermoplastic resin, polyethylene, polypropylene, polybutene-1, poly-4-methylpentene-1,
Olefinic resins such as butadiene, ethylene-vinyl acetate, ethylene-acrylic acid, ethylene-methyl acrylate, vinyl chloride, vinyl chloride-vinyl acetate, vinyl chloride-ethylene, vinylidene chloride, polyvinyl fluoride, polyvinyl acetate, polyvinyl alcohol , Polyvinyl fulmar, polyvinyl acetal, polyvinyl butyral,
Examples thereof include polyamides such as ethylene-vinyl alcohol, polymethyl methacrylate, polyacrylonitrile, and 6-nylon, and polyesters such as polyoxymethylene, polycarbonate, polyethylene terephthalate, and polybutylene terephthalate.

The thermoplastic elastomer, which depends on the ratio between the rubber phase and the resin phase, may be a thermoplastic elastomer whose thermoplasticity is sufficiently maintained. (Rubber phase) may easily flow. Examples of the thermoplastic elastomer include styrene-based thermoplastic elastomers such as styrene-butadiene block copolymers, polyurethane-based thermoplastic elastomers, ethylene-propylene copolymers, ethylene-butylene copolymers, and olefin-based elastomers such as ethylene-propylene. Examples thereof include thermoplastic elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, ethylene-vinyl-based elastomers, and ionomers.

The porous flat plate may contain a rubber-like elastic substance such as the above-mentioned thermoplastic elastomer and thermosetting rubber, but this rubber-like elastic substance does not contain a sulfur-based vulcanizing agent. It is desirable. When a rubber or a thermoplastic elastomer containing such a sulfur-based vulcanizing agent is used, an odor may be generated during laser processing.

The above-mentioned porous flat plate includes, in addition to a thermoplastic resin and a thermoplastic elastomer, a thermosetting resin such as a phenol resin, an epoxy resin and a urea resin, and acrylonitrile resin.
Synthetic rubbers such as butadiene copolymer rubber, styrene-butadiene copolymer rubber, chloroprene rubber, and butadiene rubber;
Natural rubber or the like can be used. As additives, compounding agents, or fillers, fillers such as heavy calcium carbonate, light calcium carbonate, clay, silica, and carbon black, and other additives can be added according to desired properties. . However, acrylonitrile-butadiene copolymer rubber containing a vulcanizing agent as described above,
If synthetic rubber such as styrene-butadiene copolymer rubber or ethylene-propylene-diene copolymer rubber, or natural rubber is added, an unpleasant odor is generated during laser processing, so that it is better to avoid compounding as much as possible.

Next, a method for manufacturing a stamp according to the present invention will be described. The present invention is a method of manufacturing the stamp, wherein the porous plate is made to contain a liquid substance, and the porous surface is engraved by laser irradiation to form irregularities. The laser device used for the laser irradiation is selected according to the porous flat plate to be processed. Specific examples include gas lasers such as helium, neon, argon, xenon, carbon dioxide, and nitrogen, solid lasers such as ruby, YAG, and glass, and semiconductor lasers such as gallium-arsenic and gallium-aluminum-arsenic. . The type of laser to be used is not particularly limited, but a carbon dioxide laser is generally used as a laser used for stamp production. The laser irradiation output is
The material can be appropriately selected and used depending on the material of the workpiece, the distribution state of the pores, the desired height of the unevenness, the type of the liquid substance to be impregnated at the time of processing, and the like.

The liquid substance may be any liquid substance that can be infiltrated into the porous flat plate, and the liquid substance may contain a dissolved substance or a dispersed substance. The reason that the presence of the liquid material in the pores enables the thermoplastic porous flat plate to be stamped with a laser is because the heat of the thermoplastic resin melted by the laser irradiation is converted into the liquid material in the gas phase. It is considered that the problem that the shoulder portion of the character drips is solved because heat is easily absorbed and heat is absorbed by vaporizing the liquid substance itself and suppressing the propagation of heat to the surroundings.

The liquid substance is not particularly limited as long as it is a liquid substance that can be infiltrated into the porous flat plate, but a liquid substance having a large specific heat capacity at a constant pressure has a large effect.
As a liquid having a large specific heat capacity at constant pressure, water (4.18 J /
Kg), glycerin (2.42 J / Kg), ethylene glycol (2.55 J / Kg), propylene glycol (2.52 J / Kg), methyl alcohol (2.55 J / Kg) ), Ethyl alcohol (2.47)
J / K · g) and the like. However, water is most excellent in consideration of ease of handling, odor, volatility, safety, flammability, ignitability, etc., in addition to constant pressure specific heat capacity.

The same effect can be obtained when the ink is impregnated with an aqueous ink mainly composed of water. When the liquid substance contained in the porous material is a non-aqueous ink such as alcohols, glycols, glycol ethers, ketones, esters, and hydrocarbons, the effect is lower than that of water, but the stamp surface is formed by engraving. Thereafter, ink filling is not required, and the process can be simplified.

When the porous flat plate is mainly composed of a rubber elastic material such as acrylonitrile-butadiene copolymer rubber or ethylene-propylene-diene copolymer rubber vulcanized with a sulfur-based vulcanizing agent, it may be used at the time of engraving surface processing. Residual residues are generated and require a cleaning step. For this reason, laser processing in a state where the ink is filled is impossible. On the other hand, in the case of a porous flat plate containing the thermoplastic resin or the thermoplastic elastomer, even if residual residue is generated at the time of engraving the surface, it is taken in by a molten portion of the thermoplastic resin and the like, and powder is formed on the stamp surface. Since it does not remain as granules, there is no need for cleaning, and therefore, laser processing becomes possible even in a state where the ink is impregnated.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the stamp and manufacturing method according to the present invention will be described below. The present invention is not limited to the following embodiments. The evaluation of the stamps prepared in the following Examples 1 to 8, Reference Examples 1 and 2, and Comparative Examples 1 to 5 was evaluated. The results are shown in Table 1.

(Example 1) The following porous flat plate was impregnated with the following liquid substance, and the stamp face was engraved with a carbon dioxide laser.・ Porous plate α-olefin rubber (Ethylene butylene rubber, EBR: no sulfur-based vulcanizing agent treatment) ・ Liquid substance Water (Example 2) The engraving of the stamp was performed with a laser.・ Porous flat α-olefin rubber (Ethylene butylene rubber, EBR: No sulfur-based vulcanizing agent treatment) ・ Liquid substance Oil-based pigment ink (Main solvent: Castor oil-modified product)

Example 3 The following porous plate was impregnated with the following liquid substance, and the stamped surface was engraved with a carbon dioxide gas laser. -Porous flat plate Polyvinyl formal (PVF)-Liquid substance water (Example 4) The following porous flat plate was impregnated with the following liquid substance, and the stamp face was engraved with a carbon dioxide gas laser.・ Porous flat plate polyvinyl formal (PVF) ・ Liquid substance Oil-based pigment ink (Main solvent: Castor oil-modified product)

Example 5 The following porous flat plate was impregnated with the following liquid substance, and the engraved surface was stamped with a carbon dioxide laser.・ Porous flat plate ethylene-vinyl acetate copolymer (EV
A) Liquid material Water (Example 6) The following porous plate was impregnated with the following liquid material, and the stamp face was engraved with a carbon dioxide laser.・ Porous flat plate ethylene-vinyl acetate copolymer (EV
A) ・ Liquid substance Oil-based pigment ink (Main solvent: Castor oil modified product)

Example 7 The following porous flat plate was impregnated with the following liquid substance, and the engraved surface was stamped with a carbon dioxide laser. -Porous flat plate Polyethylene sintered porous flat plate (PE)-Liquid substance water (Example 8) The following porous flat plate was impregnated with the following liquid substance, and the stamp face was engraved with a carbon dioxide gas laser.・ Porous flat plate Polyethylene sintered porous plate (PE) ・ Liquid substance Oil-based pigment ink (Main solvent: Castor oil-modified product)

(Reference Example 1) The following porous flat plate was impregnated with the following liquid substance, and the surface of the stamp was engraved with a carbon dioxide laser.・ Porous flat plate ethylene-propylene-diene copolymer rubber (EPDM: compounded with sulfur-based vulcanizing agent) ・ Liquid substance Water

REFERENCE EXAMPLE 2 The following porous plate was impregnated with the following liquid substance, and the surface of the stamp was engraved with a carbon dioxide laser. -Porous flat plate acrylonitrile-butadiene copolymer rubber (NBR: compounded with sulfur-based vulcanizing agent)-Liquid substance water

(Comparative Example 1) The following porous plate was engraved with a carbon dioxide laser on a stamped surface without being impregnated with a liquid substance. -Porous flat plate α-olefin rubber (ethylene butylene rubber, EBR: blended with sulfur-based vulcanizing agent) (Comparative Example 2) The following porous flat plate was directly impregnated with a liquid substance, and the surface of the stamped surface was irradiated with a carbon dioxide gas laser. Carved.・ Porous flat plate polyvinyl formal (PVF)

(Comparative Example 3) The following porous plate was engraved on a stamped surface with a carbon dioxide gas laser without being impregnated with the liquid material as it was.・ Porous flat plate ethylene-vinyl acetate copolymer (EV
A)

(Comparative Example 4) The following porous plate was impregnated with the following liquid substance, and the stamped surface was engraved with a carbon dioxide laser. -Porous flat plate acrylonitrile-butadiene copolymer rubber (NBR: compounded with sulfur-based vulcanizing agent)-Liquid substance Oil-based pigment ink (Main solvent: Castor oil-modified product)

(Comparative Example 5) The following porous plate was impregnated with the following liquid substance, and engraved on a stamped surface with a carbon dioxide gas laser.・ Porous flat plate ethylene-propylene-diene copolymer rubber (EPDM: compounded with sulfur-based vulcanizing agent) ・ Liquid substance Oil-based pigment ink (Main solvent: Castor oil-modified product)

[0035]

[Table 1]

In Table 1, the drooping of the above-mentioned character shoulder portion is "○: sharp ridge is obtained", "x: ridge is drooping", and is observed by an optical microscope and an electronic scanning microscope. Was evaluated by observation. The state after the stamping process was “○: no residue”, “X: large amount of residue”, “*: sticky fusion part”, and observation and processing by an optical microscope after laser processing. The part was evaluated by finger touch. The off-flavors at the time of the above laser processing are as follows: "○ has no or almost no odor", "X has bad odor",
The sensory evaluation was performed during laser processing.

In addition, the status of the seal imprint (overall evaluation) is “very good”, “good”, and “poor”. And the imprint was evaluated. In addition, as the factors of the imprint state of the seal, the blurring of the character due to the fact that the pores of the convex portion tend to be obstructed due to the heat flow, the blurring of the character due to the lack of sharpness of the character ridge, and the heat Are not sufficiently formed, so that the unevenness is not sufficiently formed.

From the results shown in Table 1, in Examples 1 to 8, there was no unpleasant odor at the time of processing, and the stamped surface state after processing was very clean without residual residue and the like. Also, the character shoulder did not sag and the ridgeline was sharp, and thus the imprinting state was good. Further, in Reference Examples 1 and 2, residual shavings and the like were generated on the stamped surface after processing, and although there was a bad smell, after washing, a sharp stamped surface with ridge lines without drooping in the character shoulder portion was obtained.

On the other hand, in Comparative Examples 1 to 3, although there was no unpleasant odor at the time of processing, problems such as lack of sharp ridge lines and inability to engrave fine characters occurred. Thus,
The imprint condition was also poor. Comparative Examples 4 and 5
In the case of, residual scum was generated on the stamped surface after processing, and an odor was also generated. In Reference Examples 1 and 2, water was used as the liquid substance, whereas in Comparative Examples 4 and 5, ink was used, and it was very difficult to remove residual residue on the stamp surface.

As described above, in the stamping of the porous flat plate according to the present invention by laser processing, in manufacturing, an unpleasant odor during processing can be reduced, cleaning after laser processing is unnecessary, and character ridge lines are clear. Thus, a seal having a good seal can be obtained.

[0041]

As described above, according to the stamp formed by laser processing of the porous flat plate according to the present invention, the surface of the porous flat plate is a stamp formed by laser processing and is not heat-sealed to the laser irradiation surface. The surface is engraved with holes, sharp imprints are obtained, no unpleasant odor is generated at the time of processing, and the state of the stamped surface after the processing is excellent.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an engraved surface of a first embodiment of a stamp according to the present invention by an optical microscope photograph.

FIG. 2 is a perspective view showing an engraved surface of the stamp according to the second embodiment of the present invention by an optical microscope photograph.

FIG. 3 is a perspective view showing an engraved surface of a stamp according to the third embodiment of the present invention by an optical microscope photograph.

FIG. 4 is a perspective view showing an engraved surface of a first form of a stamp for comparison by an optical microscope photograph.

FIG. 5 is a perspective view showing an engraved surface of a second form of a stamp for comparison by an optical microscope photograph.

Claims (6)

[Claims] 1. An engraving characterized in that the surface of a porous flat plate is a laser-processed stamp, and the laser-irradiated surface has an engraved surface having holes that are not heat-sealed. 2. The method according to claim 1, wherein the porous flat plate contains at least 20% by mass of a thermoplastic substance.
The stamp manufacturing method described. 3. The porous flat plate contains a rubber-like elastic substance,
3. The method according to claim 1, wherein said rubber-like elastic substance contains no sulfur-based vulcanizing agent. 4. A method for producing a stamp in which the surface of a porous flat plate is laser-processed, wherein a liquid substance is contained in the porous flat plate, and the laser processing is used to engrave the porous surface to form irregularities. 3. The stamp manufacturing method according to claim 2, wherein: 5. The stamp manufacturing method according to claim 4, wherein said liquid material is water. 6. The stamp manufacturing method according to claim 4, wherein said liquid material is ink.