JPH0293473A - Method and plate for electronic printing - Google Patents

Abstract

PURPOSE:To execute plate making, to decrease the deterioration of a picture quality, and also, to enhance the printing durability by arranging many pieces of minute charged elements in the vicinity of the surface of a printing plate, electrifying the element of a desired part and allowing a toner to adhere. CONSTITUTION:In the vicinity of the surface of a printing plate 6, many charged elements 11 are arranged regularly, and constituted so as to be electrified by inputting an image signal generated by signal electrodes Y1, Y2... and scanning electrodes X1, X2... between each element 11 to each element 11 through a switch element 12. In such a state, a document 1 is brought to color separation to four colors by a scanner 2, etc., a signal of one color in signals of each color is inputted, and the element 11 is electrified. Subsequently, an electrified powder toner or liquid toner is allowed to adhere to an electrified part 7, and a toner image is transferred to a body to be printed 9 such as paper, etc., by which an image 10 is obtained. Next, the same operation is executed repeatedly with regard to other color.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to printing technology, and more particularly to technology for printing using an electronic printing method.

<Prior Art> Conventionally, as a printing method, a planographic printing method, a letterpress printing method, an intaglio printing method, etc. are known. In all of these methods, a printing plate is created for each printing item, and after printing is completed, a new printing plate is usually created when printing another printing item.

In addition to this, printing is also performed using an electrostatic printing method.

<Problem to be solved by the invention> However, in printing methods such as lithography, letterpress, and intaglio, once a printing plate is created, the same printing plate material cannot be used to print a different pattern after printing is completed. However, there is a problem in that it is necessary to create a new printing plate, which increases the time and cost of printing plate materials.

In addition, in the electrostatic printing method, the printing plate material used is
It can be used again to print another pattern, making it economical.

However, in the conventional electrostatic printing method, the image pattern is formed optically, and there is a problem in that the image quality inevitably deteriorates.

Furthermore, since the method is based on an optical method, there is a problem in that a large amount of energy is required to turn on the lamp light source used therein.

Furthermore, in the conventional electrostatic printing method, since the plate material is a photosensitive material, it is necessary to process the plate material in a dark place, which is inconvenient.
The problem is that the electric charge decreases with the passage of time, and therefore there is no printing durability for printing a large number of copies.

Furthermore, in the conventional electrostatic printing method, when printing is completed and another pattern is to be printed, another original for exposure must be created for optical exposure, which shortens the printing plate process. The problem is that it does not.

Furthermore, although it is desired to develop an online printing process with a computer, this has not been realized.

Therefore, the present invention aims to provide a new electronic printing plate that solves the above-mentioned conventional problems and a new printing method using the printing plate.

That is, the present invention enables plate making with low energy without using optical means, allows printing even in bright places like ordinary lithography, letterpress, and intaglio printing methods, and furthermore, reduces image quality deterioration. There is no need to create another original for exposure when printing a different pattern, and the printing plate material can be used repeatedly, and it is also possible to print online with a computer. The purpose is to provide a new electronic print edition.

A further object of the present invention is to provide a new electronic printing method using this new printing plate.

<Means for Solving the Problems> In order to solve the above problems, the printing plate of the present invention charges the surface of the printing plate in a pattern, attaches charged toner to the charged portion, and then removes the attached charged toner. A printing plate used for printing by transferring a substance to a printing material, wherein a fine charging element is provided over almost the entire surface near the surface of the printing plate to form a charged portion on the surface of the printing plate. This is an electronic printing plate consisting of a large number of plates arranged in a regular manner. In this case, each of the charging elements can be provided with a switch element, and the charging element can be selectively charged by the switch element. Note that transistors, thyristors, etc. can be used as switching elements, and in particular, TPT, M
Semiconductors such as OSFET and old types can be used. Furthermore, each of the charging elements can be provided with a capacitor element. Furthermore, in the printing method of the present invention, in a printing plate using the electronic printing plate of the present invention as described above, electronically applying electric charge in a pattern to the charging elements formed by the plurality of regularly arranged charging elements, Printing is attempted by attaching charged toner to the charged portion and then transferring the attached charged toner to the printing object. In this case, the charged toner can be either a powder toner or a liquid toner.

Effects> The printing plate of the present invention has a large number of fine charging elements arranged regularly over almost the entire surface near the surface of the printing plate to form charged portions on the surface of the printing plate. By charging the charging element at the portion to which the toner to be printed is to be attached, a pattern-shaped charged portion to be printed is formed.

For example, if this charged part is negatively charged,
By supplying positively charged toner to the charging section, the toner adheres to the surface of the printing plate in a pattern. As long as the charges on the charging unit and the charges on the toner are opposite in polarity, either one may be positive or negative.Printing is performed by transferring this toner to a printing medium such as paper. In this case, each of the charging elements is provided with a switch element, and a current based on an image signal to be printed is inputted to a corresponding one of the charging elements, so that the charging elements are arranged in a pattern to be printed. Can be electrically charged.

In this case, by providing each of the charging elements with a capacitor element, it is possible to improve retention of the charged charge of the charged element among the charging elements.

As the above-mentioned charging element, for example, a matrix type pixel electrode used in liquid crystal displays and the like can be used.

<Example> Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram of a printing system using the printing plate of the present invention, in which a document (1) is processed using a color separation device such as a scanner (2) to distinguish yellow (Y), red (gate), eye (C), and black (black). B
k) into four colors, and these color-separated signals are converted to CP.
It is input to the arithmetic unit t (3) containing U. In this case, it can also be stored in the external storage device (4). If necessary, convert the color-separated signals into red (R), green (G), and blue (B) signals for the monitor TV and check the suitability of the color separation conditions on the monitor TV (5). The Y, M, C, and Bk signals that have been subjected to zero-order color separation may be input to each color printing plate. In the case of Figure 1, the Y signal is the printing plate for the Y plate (
6) is shown, and the other M, C, Bk
In the case of , it is omitted. Below is a brief explanation of the Y version printing plate (6
), but the same can be applied to printing plates of other colors.

Of course, when printing in one color, printing can be performed without color separation.

First, the image signal input to the printing plate (6) electronically charges the surface of the printing plate (6) in a pattern corresponding to the image of the original, and charges it with a charge opposite to the charged charge. The charged IF toner is supplied by a charged toner supply device (not shown in FIG. 1) and is deposited on the charged portion of the surface of the printing plate.

By passing the printing material (9) such as paper between the rotating printing plate (6) and the pressure IN (8), the adhered toner is transferred to the printing material (9), and the printed image (1
0) is obtained.

Next, the structure of the printing plate (6) and how to charge the printing plate in accordance with the image pattern will be explained.

The printing plate (6) has a large number of fine charging elements (11) arranged regularly over almost the entire surface of the printing plate (6) to form a charging portion near its surface.

FIG. 2 is a partially enlarged explanatory diagram of a portion (A) surrounded by a dotted line in FIG. 1. A large number of Wt elements (11) arranged near the surface of the printing plate (6) are arranged at minute intervals apart, and a signal electrode (Yl) is arranged between each charging element (11).
), (Yl)... and scanning electrodes (X, ), (Xri...
An image signal is input through. In this case, each charging element (11) is provided with a switching element (12),
A switching element corresponding to a portion of both the scanning electrode and the signal electrode through which current flows is activated, and the charging element of that portion is charged.

FIG. 3 is an enlarged explanatory diagram of the switch element part, and the fourth
The figure is an explanatory cross-sectional view of a portion taken along line B--B in FIG. 3. The switch element consists of a thin film transistor (TPT), which includes a gate electrode (20), a source electrode (21), a drain electrode (22), an insulating layer (23), and an amorphous 5il.
ii (15).

The gate electrode (20) is insulated from other electrodes by an insulating layer (23) and an amorphous Si layer (15). The drain electrode (22) is connected to the charging element (11), and the source electrode (21) is connected to the signal type 1 (Yl). Furthermore, the gate electrode (20) is a scanning electrode (X,
)It is connected to the. In this way, the charging element (11) can be selectively charged depending on the presence or absence of the scanning electrode and signal 1 current.

Note that the circuit configuration including such a charging element may be formed on a flexible base material (24) such as a synthetic resin sheet and wound around a cylindrical cylinder, or it may be formed on a plate-like base material. Of course, it is also possible to form a flat printing plate.

The charging element may be made of any material, whether transparent or opaque, as long as it has high conductivity, but metals such as copper, aluminum, silver, ITO (indium oxide, tin oxide), etc. may be used as appropriate. Can be selected and adopted. Further, in order to prevent the amount of charge charged on the charging element from decreasing, each charging element may be provided with a capacitor element. As a good material for the capacitor element, ceramic insulating materials such as Altos and Sin□, which have high wear resistance, fluororesin, silicone resin, and other polymeric insulating materials can be used.

The surface of the printing plate of the present invention is provided with a surface protective layer (not shown) for protecting the elements and circuits as described above. However, since the present invention does not require a small printing pressure, the surface protective layer is not necessarily required (this applies especially to the charging element).The electronic printing plate of the present invention having the above configuration is electronically charged with the charging element according to the image pattern of the document as described above, and the charged portion is charged. Printing is performed by adhesion of toner and transfer of the toner to the printing medium.

Incidentally, there are known charged toners in the form of liquid and powder, and in both cases printing can be carried out using the printing plate of the present invention.

FIG. 5 is an explanatory diagram showing a method of printing when liquid toner is used using the printing plate of the present invention.

The printing plate (6) of the present invention is immersed in a charged liquid toner solution. The printing plate (6) is electronically charged in a pattern according to the image pattern of the original by the method described above (in this case, it is charged with an electric charge different from that of the liquid toner).

As a result, the liquid toner adheres to the surface of the printing plate (6) in a pattern, and the toner is transferred to a printing medium (9) such as paper that passes between the impression cylinder (8) and printing is performed.

FIG. 6 is an explanatory diagram showing a printing method when powder toner is used in the printing plate of the present invention.

The printing plate (6) of the present invention is charged in a pattern according to the image pattern of the original as described above.

On the other hand, the powder toner (6), which is charged oppositely to that of the printing plate, is supplied to the printing plate (6) by a toner supply roll (1) and a magnetic brush roll (6), and adheres to the charged pattern portion. . [The powder toner remaining on the Ki Brush Roll (To) is scraped off by the doctor.

The powder toner thus adhered to the printing plate (6) is transferred to a printing medium (9) such as paper, which passes between the rotating roll (to) and the printing plate (6). In this case, the surface of the rotating roll is made of conductive rubber, and a charge opposite to that of the powder toner is applied thereto to facilitate the transfer of the powder toner to the printing material.

The powder toner transferred to the printing material is passed between the heating roll (2) and the pressure roll (to) and fixed on the printing material.

As described above, using the printing plate of the present invention, liquid toner,
Printing can be done with either powder toner.

When using liquid toner, the holding power of the liquid toner on the surface of the printing plate can be improved by forming a slight recess in the area where the charging element is present. In this case, it is necessary to apply the same charge as the powder toner to the charging element in the area where no image is to be formed to prevent the liquid toner from entering the recesses in the non-image area.

<Effects of the Invention> As explained above, by using the electronic printing plate and electronic printing method of the present invention, the following effects can be obtained.

First, the printing plate of the present invention can be charged in an image pattern by electronically charging a charging element, and there is no need for a lamp using an optical charging method as in the conventional method.

Therefore, the energy for charging becomes extremely small.

Furthermore, since it is an electronic charging method, unlike conventional optical methods, there is no need to work in a dark room, and furthermore, it is possible to prevent the charge from decreasing in the image area and improve stiffness.

Furthermore, there is no image deterioration such as image distortion as in conventional optical methods, and good printed matter can be obtained.

Furthermore, according to the present invention, even after printing one image is completed, when printing another image, only the input of an image signal is required, so there is no need to create a new original for exposure as in the conventional optical method. Furthermore, since a printing plate used once can be used repeatedly, it is possible to save costs for printing plate materials and shorten the time required to create a printing plate. Furthermore, it becomes possible to construct an online printing process with a computer. Therefore, direct printing by image transmission from a remote location is also possible.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a printing system using the printing plate of the present invention, Fig. 2 is a partially enlarged explanatory diagram of the part surrounded by the dotted line in Fig. 1, and Fig. 3 is an enlarged explanatory diagram of the switch element part. FIG. 4 is an explanatory cross-sectional view of the portion taken along line B-B in FIG. 3, FIG. 5 is an explanatory view showing a printing method when liquid toner is used in the printing plate of the present invention, and FIG. 6 is an explanatory diagram of the method of printing according to the present invention. Explanatory diagrams showing the printing method when powder toner is used for the printing plate are shown. 1... Original 2... Scanner 3... Arithmetic device 4... External storage device 5... Monitor TV 6.
...Printing plate 7...Charged part 8...
Impression cylinder 9... Printed material lO... Print image 11... Charging element 12... Switch element 15... Amorphous Si layer 16... Insulating material layer 20... Gate electrode 21... ... Source electrode 22 ... Drain electrode 23 ... Insulating layer 24 ... Base material 25 ... Liquid toner
26... Powder toner 27... Toner supply roll 28... Magnetic brush roll 29... Doctor
30... Transfer roll 31... Heating roll Patent application Hitotoppan Printing Co., Ltd. Representative Kazuo Suzuki Figure 2 Σ1 Snake Figure 3 Figure 4! r5 figure 6

Claims (5)

[Claims] (1) A printing plate used for printing by charging the surface of the printing plate in a pattern, depositing charged toner on the charged portion, and then transferring the deposited charged toner to a printing medium, . An electronic printing plate, characterized in that a large number of fine charging elements for forming charging portions on the surface of the printing plate are regularly arranged over almost the entire surface near the surface of the printing plate. (2) each of the charging elements is provided with a switch element;
2. The electronic printing plate according to claim 1, wherein the charging element can be selectively charged by the switching element. (3) The electronic printing plate according to claim 1 or 2, wherein each of the charging elements is provided with a capacitor element. (4) A printing method using the printing plate according to claim 1, which comprises electronically applying electric charge in a pattern to the plurality of regularly arranged charging elements, and adhering charged toner to the charged portions. An electronic printing method characterized in that the adhered charged toner is then transferred to a printing medium. (5) The electronic printing method according to claim 4, wherein the charged toner is either a powder toner or a liquid toner.