JPH11129596A - Endless printing belt for rotary seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endless printing belt for forming a printing unit once more regardless of after once manufacturing by selecting a most excellent base material in the case of using a thermoplastic substance for a porous unit of the belt. SOLUTION: In the endless printing belt 1 for a rotary seal comprising a hot-melt sheet as a base material 2 and a pedestal 4 made of a thermoplastic porous material molded on the sheet, a non-printing part 6 is formed of a non- porous protective film on the pedestal 4. Or, in the endless printing belt 1 for the seal comprising a hot-melt sheet placed on a reinforcing material 3 as a base material 2, and a pedestal 4 made of a thermoplastic porous material molded on the sheet, a non-printing part 6 is formed of a non-porous protective film on the pedestal 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endless printing belt using a porous body used for a rotary stamp of a type incorporating ink.

[0002]

2. Description of the Related Art JP-A-54-103127 and JP-A-54-103127
A rotating mark composed of an endless printing belt using a porous body having open cells as a printing unit disclosed in -118210 etc. can incorporate ink into itself, so that it can be continuously used without attaching ink every time it is used. It is very useful because it can be stamped. Conventionally, a sponge rubber is mainly used for the porous body of such an endless printing belt, and a cotton cloth is mainly used as a base material for complementing the strength of the rubber. Almost no change was made to other materials such as thermoplastics. This is probably because thermoplastic substances such as polyethylene and polypropylene have very poor adhesiveness to cotton cloth, and have a problem that they cannot be put to practical use when used for the endless printing belt.
In addition, in the conventional endless printing belt of rotary marking, when forming an endless printing belt, a method of simultaneously forming a printing portion such as a character, a figure, a symbol, and a pattern at the same time is used. The sculpture of the pedestal (mount) and the printing part is used in two steps. However, in this method, required characters, figures, patterns, and the like must be engraved in a mold in advance, and it has not been possible to form additional characters after the endless printing belt is manufactured.

[0003]

SUMMARY OF THE INVENTION Accordingly, the present invention has been invented for the purpose of selecting the most excellent base material when a thermoplastic material is used for a porous body of an endless printing belt. It is another object of the present invention to provide an endless printing belt capable of forming a printing portion again after production.

[0004]

According to the present invention, there is provided an endless printing belt for rotary printing comprising a hot melt sheet as a base material, and a pedestal made of a thermoplastic porous material formed on the hot melt sheet. Endless printing belt with non-printing part formed by a protective coating. In addition, in the endless printing belt for rotary marking formed by placing a hot melt sheet on a reinforcing material and forming a base made of a thermoplastic porous body on the hot melt sheet, a non-porous body is provided on the base. Endless printing belt with non-printing part formed by a protective coating. A sheet formed in a plate shape after adding and kneading at least a water-soluble bubble forming agent to a thermoplastic material is heated to 100 ° C to 200 ° C, and the heated sheet is set in a mold in which only the pedestal is engraved, A base material is placed thereon, and a pressing plate is further placed thereon, molded, and after releasing, the water-soluble bubble forming agent is washed out,
After drying, a non-printed portion is formed on the pedestal by the non-porous material protective coating, and both ends of the sheet are overlapped and heat-sealed by a heat sealing machine, and then cut to obtain endless printing for rotary printing. Belt manufacturing method. Further, a sheet formed into a plate shape by adding and mixing at least a water-soluble bubble forming agent to a thermoplastic material is heated to 100 ° C to 200 ° C, and the heated sheet is set in a mold in which only the pedestal is engraved. Then, the base material is put on it, and then a push plate is put on it, and then molded. After releasing the mold, the water-soluble bubble forming agent is washed out and dried, and both ends of the sheet are overlapped and heat-sealed with a heat sealing machine. And a method for producing an endless printing belt for rotary printing obtained by forming a non-printing portion with a non-porous material protective coating on the base.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The present invention relates to an endless printing belt for rotary printing obtained by molding a pedestal made of a thermoplastic porous material on the hot melt sheet, using a hot melt sheet as a base material. It is an endless printing belt in which a portion is formed. The substrate used in the present invention has a temperature of 50 ° C to 180 ° C.
A hot melt sheet made of a thermoplastic resin that melts at ℃ can be used. As the material, for example, polyethylene, polypropylene, vinyl chloride and the like can be used, and polyethylene is particularly preferably used.
As the hot melt sheet of the present invention, a hot melt sheet which does not shrink due to the heat formed into a sheet without applying stretchability is used in order to prevent defects during molding of the endless printing belt. Further, as the hot melt sheet of the present invention, either a non-porous or porous sheet can be used. When a non-porous sheet is used, ink cannot be supplied from the back side of the endless printing belt, so ink is supplied from the printing portion surface.When a porous sheet is used, the endless printing belt is not used. The ink can be supplied from the back side or from the surface of the printing section. From the viewpoints of moldability, adhesiveness, and ink permeability, a particularly preferable base material in the present invention has a basis weight of 10 to 30 g / m ² ,
It is a hot melt sheet of polyethylene having a lattice network structure with a thickness of 0.05 to 0.50 mm and a mesh size of 1 to 2 mm. A thermoplastic porous body is used for the base of the present invention. As the material, a thermoplastic resin mainly melting at 50 ° C to 180 ° C is used, for example, polyethylene, polypropylene,
Although vinyl chloride and the like can be used, polyethylene is particularly preferably used. In the present invention, in order to obtain a porous body having open cells, at least a water-soluble bubble forming agent such as sodium chloride or calcium chloride is added to the thermoplastic resin and kneaded, and then the water-soluble bubble forming agent is molded. Wash out to make it porous. When producing the porous body, a heat generating material fine powder that absorbs infrared rays and generates heat, such as carbon black, may be added and kneaded in addition to the water-soluble bubble forming agent. To form a porous body, there is also a method of forming open cells by mixing a foaming agent with a thermoplastic resin, but it is not preferable because it is difficult to obtain continuous cells having a uniform size. In addition,
In the present invention, a mold is used in which only the pedestal is engraved and the printed portions of characters, symbols, figures, pictures, etc. are not engraved. Therefore, only the pedestal is formed on the molded sheet, and the printed portion is not formed at all.

In order to form a printed portion on the pedestal, a positive film in which required characters and the like are represented by a black background and margins are represented by a transparent background, and a negative film in which required characters and the like are represented by a transparent background and the margins are represented by a black background are used. Overlaid on the pedestal, irradiated with infrared light from the film side, the portion corresponding to the blank is melted and solidified to form a non-printing portion with a non-porous material protective coating that does not allow ink to ooze out, and a portion corresponding to characters etc. Remain so that the ink can be exuded to form a printed portion. In this case, if the thermoplastic porous material contains a heating material fine powder that absorbs infrared rays and generates heat, use a positive film.If the thermoplastic porous body does not contain a heating material fine powder, use a negative film to write characters and the like. Form. The method for creating characters and the like by infrared irradiation is described in JP-B-53-43321 and JP-A-6-15569.
8, Japanese Patent Application Laid-Open No. 8-72376, Japanese Patent Application No. 8-272200, etc., have already become known technologies. Further, as another printing portion forming method, after incorporating an endless printing belt on which a printing portion is not formed into a conventionally known rotary mark, a mold engraving required characters and the like is heated to about 80 ° C. The rotating mark is moved while rotating the endless printing belt on the top, and the portion corresponding to the margin other than characters etc. is melted and solidified to form a non-printing part with a non-porous material protective coating that does not allow ink to ooze out, There is also a method of forming a printed portion by leaving a portion corresponding to the above so as to allow ink to seep out. In any case, if an endless printing belt with only a pedestal in which characters and the like are not formed at first is manufactured, an endless printing belt in which the required characters and the like are formed in a necessary quantity can be obtained later when necessary. Therefore, there is no need to keep an inventory of useless finished products.

The endless belt of the present invention is manufactured as follows. At least a water-soluble bubble-forming agent such as sodium chloride or calcium chloride is added to a thermoplastic substance such as polyethylene, and if necessary, a heating material fine powder such as carbon black is added and kneaded to form a sheet formed into a plate shape. 1
After heating to 00 ° C to 200 ° C, the heated sheet is set in a mold in which only the pedestal is engraved, a base material is placed thereon, and a pressing plate is further placed thereon, molded, released, and then the aqueous solution is released. After washing out the porous foam-forming agent and drying, a non-printing portion is formed on the pedestal by the non-porous material protective coating by the method described above, and both ends of the sheet are overlapped and heat-sealed by a heat sealing machine. The sheet is manufactured by cutting, or after drying, the both ends of the sheet are overlapped and heat-sealed by a heat sealing machine, cut into a required width, and then protected on the pedestal by the method described above. It is manufactured by forming a non-printed portion with a coating. In the present invention, a printing belt is manufactured by heating a sheet formed into a plate shape by adding a water-soluble bubble-forming agent as described above. Therefore, the mold need not be heated at all or kept at a low temperature, and there is no need to heat the mold to a high temperature. In addition, any material such as a phenol plate having a melting point of 200 ° C. or more can be used without any particular limitation. In addition,
A sheet formed into a plate by adding a water-soluble bubble-forming agent
The reason for heating to 0 ° C to 200 ° C is to soften the sheet as much as possible to improve moldability. Here, it is considered that the sheet contains a water-soluble bubble forming agent, but does not melt even when heated to 160 ° C. The heating method is
A method of placing the sheet on a hot plate or heating with a microwave is used, and the method is not particularly limited as long as the entire sheet is heated. In the present manufacturing method, both ends of the sheet after washing out the water-soluble bubble forming agent are overlapped and heat-sealed with a heat sealing machine, but the material is not a thermosetting resin such as rubber but a thermoplastic resin. Therefore, there is an advantage that a special adhesive is not required and heat fusion can be performed as it is.

Further, if the above-mentioned base material of the endless printing belt for rotary printing is reinforced with a hot melt sheet by a reinforcing material, a better endless printing belt can be obtained. As the reinforcing material, a cloth in which fibers such as cotton, silk, rayon, nylon, and polyester are mainly woven or twill-woven can be used.
Various cloths using the above natural fibers can be used. As the hot melt sheet and the thermoplastic porous body, the same ones as described above can be used. In this case, the hot melt sheet naturally acts as a base material, but not only synthetic fibers but also natural fibers such as cotton. Since it is strongly bonded, it also acts as an adhesive between the reinforcing material and the thermoplastic porous body.

[0009]

The present invention will be described below in detail with reference to examples. Example 1 is shown in FIG. 2 is a substrate, 70 ° C.
A hot-melt sheet made of a porous polyethylene having a thickness of 0.2 mm, which is melted by the above method, is used. As the hot melt sheet, a sheet which is formed into a sheet without imparting stretchability and does not shrink by heat is selected. As a result, it is possible to prevent defects during molding of the endless printing belt. Reference numeral 4 denotes a pedestal, which is made of porous polyethylene which melts at 70 ° C. The pedestal 4 has a printed portion 5 and a non-printed portion 6 formed thereon, and the non-printed portion 6 melts and solidifies a portion of the porous polyethylene in a portion corresponding to a margin other than characters and the like so that the ink cannot ooze out. The printing portion 5 is obtained by forming a non-porous material protective film, and the printing portion 5 is formed such that a portion corresponding to a character or the like does not melt and solidify but remains so as to allow ink to seep out. By melting and solidifying the porous polyethylene, the difference in height between the printed portion 5 and the non-printed portion 6 becomes about 0.01 mm to 1.0 mm. Next, the manufacturing method of this embodiment will be described. First, sodium chloride fine powder and carbon black are added to a polyethylene resin and kneaded to produce a plate-like sheet having a thickness of 2 mm. Next, this plate-shaped sheet is heated to 140 ° C. by a hot plate. Next, a release agent is applied to a mold in which only the pedestal is engraved, and the heated plate-shaped sheet is set therein, and a hot-melt sheet of polyethylene porous material having a thickness of 0.2 mm is placed thereon. Then, a pressing plate is placed thereon and molded by a press for 30 seconds while applying a pressure of 200 kg / cm ² . Thereafter, the sheet is released and the molded sheet is taken out. Next, the molded sheet is immersed in warm water to wash out the sodium chloride and dried when the sodium chloride is completely removed. After sufficient drying, a positive film in which required characters and the like are expressed in black and the margin is expressed in transparent is overlaid on the pedestal, and infrared rays are irradiated from the film side. Then, in the transparent portion of the positive film, the infrared rays penetrate and generate heat in the corresponding portion of the carbon to melt and solidify the sheet to form a non-porous material protective coating, and the black portion of the positive film generates heat by the infrared ray. Until the corresponding part of the porous body is melted, the porous body remains without transmitting the temperature. Therefore, the pedestal is formed in a printed portion where ink can be exuded and a non-printed portion where ink cannot be exuded. Next, both ends of the sheet are overlapped and heat-sealed by a heat sealing machine. The endless printing belt of this embodiment is obtained by cutting the thus obtained one to a required width. Then, ink is supplied dropwise from the substrate side of the endless printing belt, and the ink is incorporated into a known rotary mark for use. Here, a sheet formed by adding sodium chloride fine powder to a polyethylene resin that melts at 70 ° C. and shaped into a plate is 140 ° C.
Does not melt when heated to

Next, a second embodiment is shown in FIG. Reference numeral 2 denotes a substrate, which uses a hot melt sheet made of a porous polyethylene having a thickness of 0.5 mm and melting at 80 ° C. As the hot melt sheet, a sheet which is formed into a sheet without imparting stretchability and does not shrink by heat is selected. As a result, it is possible to prevent defects during molding of the endless printing belt. Reference numeral 4 denotes a pedestal made of porous polyethylene which melts at 80 ° C. The pedestal 4 has a printed portion 5 and a non-printed portion 6 formed thereon, and the non-printed portion 6 melts and solidifies a portion of the porous polyethylene in a portion corresponding to a margin other than characters and the like so that the ink cannot ooze out. The printing portion 5 is obtained by forming a non-porous material protective film, and the printing portion 5 is formed such that a portion corresponding to a character or the like does not melt and solidify but remains so as to allow ink to seep out. By melting and solidifying the porous polyethylene, the difference in height between the printed portion 5 and the non-printed portion 6 is 0.01 m.
m to about 1.0 mm. 3 is a reinforcing material, 12
A cotton cloth is used in which a zero-numbered twin yarn is plain-woven at 120 yarns / inch. Next, a manufacturing method of the second embodiment will be described. First, sodium chloride fine powder is added to a polyethylene resin and kneaded to produce a plate-like sheet having a thickness of 2 mm. Next, the plate-like sheet is placed on a hot plate at 140
Heat to ° C. Next, a release agent was applied to a mold in which only the printing portion of the pedestal was engraved, and the heated plate-like sheet was set therein, and a polyethylene porous body having a thickness of 0.5 mm was placed thereon.
mm hot-melt sheet, and a cotton cloth woven with 120-count twin yarn plain and woven at 120 yarns / inch on top of it, then put a push plate on it and mold it with a press for 30 seconds while applying a pressure of 200 kg / cm ^2. I do. Thereafter, the sheet is released and the molded sheet is taken out. Next, the molded sheet is immersed in warm water to wash out the sodium chloride and dried when the sodium chloride is completely removed. After sufficient drying, both ends of the molded sheet are overlapped and heat-sealed by a heat sealing machine. The resulting material is cut to the required width and incorporated into a rotary stamp. Next, the mold engraved with the required characters and the like is heated to about 80 ° C., and the rotation mark is moved while rotating the endless printing belt on the mold to melt and solidify the margins other than the characters and the ink bleeds. An endless printing belt according to the present embodiment is obtained by forming a non-porous material protective coating which cannot be discharged and forming only a portion such as a character so as to allow ink to bleed out. Then, different inks are dripped and supplied from the surface of the printing portion to each printing portion, and the ink is used by being incorporated into a known rotary mark. Here, the hot melt sheet naturally functions as a base material, but also firmly adheres to the cotton cloth, and thus also functions as an adhesive between the reinforcing material and the thermoplastic porous body.

[0011]

According to the present invention, when a thermoplastic material is used for an endless printing belt for rotary printing, a hot melt is selected as a base material. The endless printing belt which can be obtained was obtained. In addition, only the pedestal without the printing part is manufactured once,
The endless printing belt that can form the printing section later can be used again, so that an endless printing belt can be obtained in which the required number of necessary characters and the like are formed when needed. There is no need to keep it. In addition, in the present invention, the endless printing belt is manufactured by heating the plate, adding the water-soluble bubble forming agent, and heating the sheet, instead of heating the mold, so that an expensive temperature control device is not required. The apparatus can be simplified and the mold itself has a melting point of 20.
Any material having a temperature of 0 ° C. or higher can be used without particular limitation. In this manufacturing method, both ends of the sheet after washing out the water-soluble bubble forming agent are overlapped and heat-sealed with a heat sealing machine. However, since the material is a thermoplastic resin, a special adhesive is not required and the heat is applied as it is. There is an advantage that it can be fused.

[0012]

[Brief description of the drawings]

FIG. 1 is an endless printing belt according to a first embodiment of the present invention.

FIG. 2 is an endless printing belt according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Endless printing belt 2 Substrate 3 Reinforcement 4 Pedestal 5 Printing body 6 Non-printing part

Claims (4)

[Claims] 1. An endless printing belt for rotary printing comprising a hot-melt sheet as a base material and a pedestal made of a thermoplastic porous material formed on the hot-melt sheet, wherein a non-porous material protective coating is formed on the pedestal. Endless printing belt with printing section. 2. An endless printing belt for rotary marking, wherein a hot melt sheet is placed on a reinforcing material to form a base material, and a pedestal made of a thermoplastic porous material is molded on the hot melt sheet. Endless printing belt with non-printing part formed by non-porous material protective coating. 3. A sheet formed into a plate by adding at least a water-soluble bubble-forming agent to a thermoplastic substance and kneading the mixture to form a sheet.
After heating to 0 ° C to 200 ° C, the heated sheet is set in a mold in which only the pedestal is engraved, a base material is placed on the sheet, a pressing plate is further placed on the sheet, molded, released, and then the aqueous solution is released. After washing out the foam-forming agent and drying, a non-printing portion is formed on the pedestal by the non-porous material protective coating, and both ends of the sheet are overlapped and heat-sealed with a heat sealer, and cut. 3. The method for producing an endless printing belt for rotary marking according to claim 1 or claim 2. 4. A sheet formed into a plate shape by adding at least a water-soluble bubble-forming agent to a thermoplastic material and kneading the mixture to form a sheet.
After heating to 0 ° C to 200 ° C, the heated sheet is set in a mold in which only the pedestal is engraved, a base material is placed on the sheet, a pressing plate is further placed on the sheet, molded, released, and then the aqueous solution is released. 2. A non-printing portion formed by a non-porous material protective coating on the pedestal, wherein the non-printing portion is formed on the pedestal by washing out the porous foam-forming agent, drying the sheet, and superposing the both ends of the sheet on each other and heat-sealing the sheet with a heat sealer. 3. The method for producing an endless printing belt for rotary marking according to claim 2.