JP2002172844A - Printing method, regenerating method of printing sheet, and printing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing method, a regenerating method of a printing sheet, and a printing sheet wherein a printing object can be smoothly reutilized. SOLUTION: The printing sheet 1 is composed of a polypropylene and a large number of recesses 2 are formed on the surface thereof. The ratio of the area of openings of the recesses to the area of the sheet 1 is 5-80%, and the equivalent circle diameter is 5-200 μm if the opening of the recess is assumed to be a circle. As an image forming material, an oil ink 3 is used. Ink transferred to the sheet 1 by printing drops into the recess 2 and is held therein in a spherical form and hence it is not fixed onto the sheet 1. For recycling the sheet 1, a cleaning roller 4 composed of an elastic material is brought into contact with the surface of the sheet 1 and rolled. The oil ink 3 in the recess 2 attaches to the surface of the roller 4 so as to be removed from within the recess 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing method, a printing sheet reproducing method and a printing sheet used in a recycling system for erasing and reusing a printed image on a printing sheet.

[0002]

2. Description of the Related Art Heretofore, there has been a strong demand for this main recycling technology, and various proposals have been made. For example,
For a copy by PPC, there is a method of separating and transferring and collecting toner from paper by reheating.

Further, a so-called electronic paper has been proposed in which fine particles are mixed and held in a sheet to move a coloring material by electrophoresis, or fine particles are colored and rotated by a magnetic field or an electric field to generate contrast. I have. This electronic paper has been recently attracting attention as a printing method that does not require ink, and is expected as an advertising panel or a recyclable printing medium.

[0004]

In the above-mentioned method of separating and collecting toner from paper by reheating in a copy by PPC, the apparatus for separation and collection becomes large, the cost becomes excessive, and the processing speed becomes slow. It was impossible for practical use.

Further, the above-mentioned electronic paper has a problem in that the cost is high due to its structure, and the cost increases as the resolution is further increased.

The present invention provides a printing method, a printing sheet reproducing method, and a printing method that can perform a printing ink collection process at a high speed and at a low cost in a simple system and can easily reuse a printing medium. The purpose is to provide a seat.

[0007]

According to the printing method of the present invention, the image forming material (oil-based ink 3, water-based ink, (Toner) in an unfixed state to form an image.

According to a second aspect of the present invention, there is provided a method for regenerating a print sheet, wherein the plurality of recesses formed in the print sheet.
An image forming material which forms an image while being held in a non-fixed state is removed from the concave portion.

According to a third aspect of the present invention, in the method for regenerating a print sheet according to the second aspect, the print sheet is subjected to an oil-repellent treatment, and the image forming material is oil-repellent. An ink (3), characterized in that the oil-based ink is held in the recess (2) by stencil printing.

According to a fourth aspect of the present invention, there is provided a method for regenerating a printed sheet according to the second aspect, wherein the concave portion is filled with an ink absorbent. The image forming material is a water-based ink, and the water-based ink is an inkjet (inkjet device 4).
0) is retained in the recess.

According to a fifth aspect of the present invention, there is provided a method of reproducing a print sheet according to the second aspect, wherein the image forming material is a powdery resin toner, and It is characterized in that it is held in the concave portion (2) by electrostatic copying (electrostatic copying device 50).

According to a sixth aspect of the present invention, there is provided a method for regenerating a printed sheet according to the third or fourth or fifth aspect, wherein the resilient member has elasticity capable of entering the recess. The image forming material is removed by rolling a roller formed of a material (a cleaning roller 4) in contact with the surface of the print sheet.

A printing sheet (1) according to claim 7
Is characterized in that a large number of recesses (2) for holding the image forming material in a non-fixed state are formed.

A printing sheet according to claim 8 (1).
The printing sheet according to claim 7, wherein a material of the printing sheet is polypropylene.

A printing sheet (1) according to claim 9
The printing sheet according to claim 7, wherein the ratio of the area of the opening of the recess (2) to the area of the printing sheet is 5 to 80%, and the equivalent circular diameter when the opening is regarded as a circle is 5%. ２００200 μm.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing a state in which a printed print sheet of this example is being regenerated, and FIG. 2 is a cross-sectional view schematically showing the structure of a stencil printing apparatus used in this example.

As shown in FIG. 1, the printing sheet 1 of this embodiment
Is made of a material capable of holding an image forming material such as ink in a non-fixed state (that is, without penetrating), for example, polypropylene. A large number of recesses 2 are formed on the surface. The shape of the concave portion 2 has a substantially circular opening in plan view, and is substantially hemispherical in three dimensions. The ratio of the area of the opening of the recess 2 to the area of the printing sheet 1 is 5 to 80%. When the opening is regarded as a circle, the equivalent circular diameter is 5 to 200 μm. In this example, the material itself is ink-repellent, but another material may be used, and in that case, the surface may be processed to be ink-repellent.

In this embodiment, the oil-based ink 3 is used as an image forming material. Solvent-based inks are not used in this example because they easily permeate the print medium. By the combination of the oil-based ink 3 and the polypropylene that is the material of the printing sheet 1,
The ink does not soak into the print sheet 1 and is fixed. The behavior of the fine ink mass on the surface of the printing sheet 1 having the fine concave portions 2 has a great influence not only on gravity but also Coulomb force when viewed microscopically. The printing sheet 1 is ink-repellent as a whole, and the ink transferred to the printing sheet 1 by printing is not stable on the flat surface between the recesses 2 and falls into the recesses 2, and furthermore, FIG. As shown in (2), the ink entering the concave portion 2 is held in a spherical shape and is not fixed to the print sheet 1.

The image formed on the printing sheet 1 is
Since the ink is not fixed on the printing sheet 1, the ink does not adhere to the finger even if the surface of the sheet is touched by the finger, and the surface of the sheet is not stained.

When the printing sheet 1 is to be recycled, as shown in FIG. 1, a cleaning roller 4 made of an elastic material having elasticity that can enter the concave portion 2 is brought into contact with the surface of the printing sheet 1 to roll. (Or move the print sheet 1 to rotate the roller at one location). The cleaning roller 4 is, for example, a silicon rubber-based material, and its hardness is 4 as Asker C hardness measured by a spring type hardness tester C type (Asker C) specified in JIS K6301 (established in 1975). ° to 15
° is preferred. By the above operation, the oil-based ink 3 in the concave portion 2 adheres to the surface of the cleaning roller 4 and is removed from the concave portion 2 cleanly. The cleaning roller 4 is provided with a removal blade 5, and the oil-based ink 3 attached to the surface is scraped and separately processed.

The printing sheet 1 of this embodiment can be formed, for example, by the following steps. A sheet of polypropylene having an appropriate thickness is heated and softened, and the sheet is nipped and conveyed between a roller having a plurality of convex portions corresponding to the concave portions 2 and another opposing roller. A large number of the concave portions 2 are formed in the sheet to obtain the print sheet 1 of the present example.

A stencil printing apparatus provided with a mechanism for regenerating the printed print sheet 1 of the present embodiment will be described. As shown in FIG. 2, an image reading unit 11 is provided at an upper part of the main body 10. The image reading unit 11 is a mechanism that reads an original placed on a transparent placing surface by an image sensor 12 that moves. An image writing unit 13 is provided below the image reading unit 11 in the main body 10. The image writing unit 13 includes a roll-shaped stencil sheet S, a thermal head 14 and a platen roller 15 for making the stencil sheet S, a transport roller 16, and a cutter 17 for cutting the stencil sheet S. The image writing unit 13 is driven based on the image information obtained by the image reading unit 11. A perforated image corresponding to the image of the document is formed on the stencil sheet S by the thermal head 14.

As shown in FIG. 2, in the main body 10,
Regarding the transport direction of the stencil sheet S, the image writing unit 1
Next to 3 is a printing unit 18. The printing unit 18 includes a printing drum 19 having a peripheral wall that is rotatably driven and has an ink passage property. An ink supply device is provided inside the printing drum 19, and supplies oil-based ink to the inner surface of the printing drum 19. A press roller 20 is provided below the print drum 19 so as to be able to move up and down. The printing sheet 1 is supplied between the press roller 20 and the rotating printing drum 19. The press roller 20 rises to print the print sheet 1 on the print drum 19.
Sandwich between The printing sheet 1 is a rotating printing drum 19.
And the peripheral wall of the printing drum 19 and the stencil sheet S
The ink that has passed through the perforated portion is transferred and printed on the print sheet 1 and sent out.

As shown in FIG. 2, in the main body 10,
On the side opposite to the image writing section 13 with respect to the printing drum 19, a plate discharging section 21 is provided. The plate discharge section removes the used stencil sheet S wound around the printing drum 19 and stores it in the plate discharge box 23 when performing plate making and printing based on a new document.

As shown in FIG. 2, in the main body 10,
Below the plate discharging section 21, there is a paper feed table 24. Paper feed table 2
The plurality of print sheets 1 stacked on the print sheet 4 are sent out one by one by a pickup roller 25 in order from the top.
The fed print sheet 1 passes through the guide roll 26, the cleaning device 6, and the timing roll 27, and
8

The cleaning device 6 includes the above-described cleaning roller 4, an opposing roller 7 opposing the cleaning roller 4, and a removal blade 5 that comes into contact with the cleaning roller 4 and collects ink adhering to the surface. In this example, since the print sheet 1 sent to the printing unit 18 passes through the cleaning device 6, the print sheet 1 on which an image has been printed and an image has been formed can be used again. That is, with the print image of the print sheet 1 facing upward,
When the print sheet 1 is stacked, the image surface of the print sheet 1 comes into contact with the cleaning roller 4 so that the ink in the concave portion 2 is removed by the above-described operation, and the print sheet 1 is printed in a reproduced state.

As shown in FIG. 2, in the main body 10,
At the lower right of the image writing unit 13 is a paper discharge unit 28. The separation claw 29 peels off the printing sheet 1 stuck to the printing drum 19. The paper discharge device 30 sucks and conveys the printed print sheet 1 peeled off from the print drum 19 and stacks it on the paper discharge table 31.

A second example of the embodiment of the present invention will be described with reference to FIG. The configuration of the print sheet 1 of this example is the same as that of the first example. The print image is formed using the inkjet device 40. The oil ink 3 is used as the ink. According to this embodiment, substantially the same effects as those of the first embodiment can be obtained.

A third embodiment of the present invention will be described with reference to FIG. The configuration of the print sheet 1 of the present example is the same as that of the first example, except that each concave portion 2 is filled with an ink absorbent 8. The ink absorbent 8 includes a hydrophilic binder and inorganic fine particles. Gelatin, polyvinyl alcohol, or the like is used as the hydrophilic binder. As the inorganic fine particles, fine particle silica or colloidal silica is used. The printed image is formed using an inkjet device. Water-based ink is used as the ink. According to this example, the ink in the concave portion 2 does not become spherical as in the first example, but is absorbed by the ink absorbent 8 and the printing sheet 1
Is held in the concave portion 2 without fixing. Therefore, while the image is formed clearly and does not transfer to the hand, the ink absorbing agent 8 that has absorbed the ink by the above-described cleaning means such as the cleaning roller 4 can be easily removed, and the image can be erased cleanly. it can.

A fourth embodiment of the present invention will be described with reference to FIG. In this example, a normal electrostatic copying machine is used as an image forming unit. The image forming material is a resin toner unlike the inks of the above-described examples. As shown in FIG. 5, the photoconductor roller 51 is charged by a charging device 52, an image is written on the charged surface of the photoconductor roller 51 by an exposure device 53, and an image is formed on the photoconductor roller 51 by a developing device 54 in an image shape. Toner adheres. On the other hand, the printing sheet 1 charged in the transfer device 55 comes into contact with the photoreceptor roller 51 to attract toner and adhere to the surface thereof to form an image. Here, the concave portion 2 side of the print sheet 1 faces the photoconductor roller 51. The toner is held in the recess 2 of the print sheet 1. The print sheet 1 is a photosensitive roller 5
After being discharged from the printer 1, the sheet passes through a fixing roller 56. Unlike the case of use as a normal electrostatic copying machine, the fixing roller 56 only carries and does not heat the toner of the print sheet 1 but melts the toner of the print sheet 1. It does not settle on the sheet.

According to this embodiment, since the unfixed toner in the concave portion 2 of the print sheet 1 forms an image, the toner can be easily removed from the concave portion 2 by the cleaning roller 4 described above. it can.

As the printing sheet 1 used in this embodiment, an electrostatic sheet in which electric charges are encapsulated during manufacturing may be used. In this case, the transfer device may not be used when forming an image using the electrostatic copying apparatus.

[0033]

According to the present invention, an image is formed by holding an image forming material in a non-fixed state inside a large number of recesses formed in a print sheet, so that it is easy to remove the image forming material from the recesses. Therefore, the image forming material can be recovered at a high speed and at a low cost by simple means, and the printed sheet can be easily reused.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment.

FIG. 2 is a schematic structural view of a stencil printing apparatus used in the first embodiment.

FIG. 3 is a cross-sectional view illustrating a second embodiment.

FIG. 4 is a sectional view showing a third embodiment.

FIG. 5 is a schematic diagram showing a fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Printing sheet 2 ... Concave part 3 ... Oil-based ink as image forming material 4 ... Cleaning roller 6 ... Cleaning device 8 ... Ink absorbent 40 ... Inkjet device 50 ... Electrostatic copying device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B41M 1/12 B41M 1/12

Claims (9)

[Claims] 1. A printing method for forming an image by holding an image forming material in a non-fixed state in a concave portion of a print sheet on which a large number of concave portions are formed. 2. An image forming material, which is held in a non-fixed state in a large number of recesses formed in a print sheet to form an image,
A method for reproducing a printed sheet, comprising: removing the printed sheet from the concave portion. 3. The printing sheet reproducing method according to claim 2, wherein the printing sheet has been subjected to an oil-repellent treatment, the image forming material is an oil-based ink, and the oil-based ink is held in the recess by stencil printing. . 4. The method according to claim 2, wherein the concave portion is filled with an ink absorbent, the image forming material is a water-based ink, and the water-based ink is held in the concave portion by inkjet. . 5. The method according to claim 2, wherein the image forming material is a powdery resin toner, and the resin toner is held in the concave portion by electrostatic copying. 6. The image forming material is removed by rolling a roller formed of an elastic material having elasticity that can enter the concave portion by contacting the roller with the surface of the printing sheet. Item 6. The method for regenerating a printed sheet according to item 3, 4, or 5. 7. A printing sheet having a large number of recesses in which an image forming material is held in a non-fixed state. 8. The printing sheet according to claim 7, wherein the material of the printing sheet is polypropylene. 9. The method according to claim 7, wherein a ratio of an area of the opening of the concave portion to an area of the printing sheet is 5 to 80%, and an equivalent circular diameter when the opening is regarded as a circle is 5 to 200 μm. Print sheet.