JPS6025786B2 - electrostatic offset printing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic offset printing machine, and more particularly to a method for uniformly corona charging an electrostatic printing master plate having an insulating part and a conductive part on a conductive support. alms,
Related to an electrostatic offset printing machine that repeats the process of developing toner using a magnetic brush method, etc., electrostatically transferring the toner to a conductive rubber transfer roll, and then corona-transferring the toner onto a transfer target and fixing it. It is.

Here, electrostatic printing master plates use a master plate that forms an insulating pattern on a conductive substrate, which is famous for its zero printing method in the past, and a photoreaction of an organic compound. Research is currently being conducted into master plates, but the currently commercially available copying method using the MagneDry method, which uses zinc oxide photosensitive paper and conductive toner, can also be used as an electrostatic printing master plate. The image area of this master plate made of conductive toner becomes a conductive part, so when it is attached to this electrostatic offset printing machine and printed, it is necessary to use reversal development. It has many advantages, such as being able to easily create a master plate and not requiring cleaning because the polarity of the corona charge and the polarity of the toner are the same in printing machines. subordinate,
Simple offset printing is widely used for office printing, but because it uses water and ink, it is not easy to handle.

Recently, the Xerox920, I
BM・M, KODAKEKTAPRINT appeared, but the machine was large and complicated, and the price of that machine was very high, and the unit copy price was not that low. An object of the present invention is to provide an electrostatic offset printing machine that performs electrostatic printing without repeating image exposure for each sheet, like an electrophotographic copying machine, and that can easily print about 10 to 100 copies. be.

Next, the electrostatic offset printing machine of the present invention will be described in detail below with reference to the drawings.

First, a plate fixing mechanism 3 that wraps and fixes the electrostatic printing master plate 1 directly around the metal drum 2, a charging mechanism 4 that uniformly charges the electrostatic printing master plate 1, and the charged electrostatic printing A toner developing mechanism 6 develops the master plate 1 with a two-component developer consisting of toner 5 and a carrier, and a toner image is transferred from the electrostatic printing master plate 1 to a conductive rubber transfer roll 7 to form a reverse image of the toner image. A reverse image adjustment mechanism 8 that temporarily holds the toner image, a corona charging transfer mechanism 9 that appropriately transfers the toner image on the conductive rubber transfer roll 7 to a transfer object such as paper, and a reverse image adjustment mechanism 9 that temporarily holds the toner image on the conductive rubber transfer roll 7, and It consists of a fixing mechanism 10 that fixes the toner image of the image, and a discharge mechanism 12 that discharges the fixed transfer object to a transfer object discharge section 11.

Each mechanism will be explained in more detail below with reference to the drawings.

The plate fixing mechanism 3 consists of a grounded non-ferrous metal drum 2 such as aluminum, and claws 13 and 14 that fix the electrostatic printing master plate 1 to the positioning layer on the outer peripheral surface of the drum. A driven shaft 151 is attached and rotated clockwise at a constant speed.

Due to this rotation, the electrostatic printing master plate 1 fixed to the orientation calendar on the outer peripheral surface of the drum is transferred to the charging mechanism 4 and the toner phenomenon mechanism 6. The electrostatic printing master plate 1 transferred to the charging mechanism 6 is uniformly charged by the corona charger 16, and the charge on the conductive portion of the electrostatic printing master plate 1 escapes to the metal drum 2, forming a static latent image. be done. Next, the toner developing mechanism 6 includes a magnetic brush 17, a toner supply roll 18, and a toner storage device 1.
The magnetic brush 17 is driven by an appropriate power, and the toner 5 is carried onto the surface of the electrostatic printing master plate 1 by the magnetic brush 17 and developed. The toner 5 consumed during development is stored in a toner storage device 19.
The amount of toner replenishment is controlled by a toner replenishment roll 18. The toner image on the electrostatic printing master plate 1 is then sent to a reverse image adjustment mechanism 8. The reverse bale adjustment mechanism 8 is composed of a conductive rubber transfer roll 7, and the toner 5 is transferred to the electrostatic printing master plate 1 by applying an exposure field having a polarity different from that of the toner 5 on the electrostatic printing master plate 1. The conductive rubber transfer roll 7
transfer to. Furthermore, it is transferred to the corona charging transfer mechanism 9. By the corona charging transfer mechanism 9, the toner 5 on the conductive rubber transfer roll 7 is supplied from the transfer material supply section 20 through the paper feed roll 21, guide rolls 22, 23, and guide plate 241, and is guided to a piece of paper. Corona transfer onto 25. This corona transfer is performed by a corona charger 26 which applies a corona discharge having a polarity different from that of the toner 5 to the back side of the paper piece 25 in contact with the conductive rubber transfer roll 7. The paper piece 26 on which the toner has been transferred is then peeled off from the conductive rubber transfer roll 7 by a peeling claw 27, sent to the fixing mechanism 10, fixed by the heat fixing rolls 28 and 29, sent to the ejection mechanism 12, and transferred to the pseudo paper table 30'. Accumulated. The present invention exhibits the following various effects because of the above configuration.

First, the electrostatic offset printing machine of the present invention does not require dampening water, adjusting the amount of ink, cleaning the printing machine after use, etc., compared to simple offset printing machines that are widely used for office printing. In addition, compared to xerographic electrophotographic copying machines, it does not require image exposure for each sheet, so it can print at extremely high speed, and it is also structurally simple and has high mechanical stability. The practical effects of the present invention are extremely large, such as being superior in that stable printed matter can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic structural side view of an electrostatic offset printing machine embodying the present invention. 1... Electrostatic printing master plate, 2... Metal drum, 3
... Plate fixing mechanism, 4... Charging mechanism, 5...
... Toner, 6 ... Toner development mechanism, 7.
... Conductive rubber transfer roll, 8 ... Reverse image adjustment mechanism, 9 ... Corona charging transfer mechanism, 10 ...
・Fixing mechanism, 11... Transferred object discharge section, 12...
...Ejection mechanism, 13, 14...Claw, 15...
...Wisteria, 16...Corona charger, 17...
. . . Magnetic brush, 18 . . . Toner supply roll, 19 . . . Toner storage device, 20 . 23...
...Guide roll, 24...Guide plate, 25...
...Paper piece, 26...Corona charger, 27...
Peeling nail, 28, 29...Heat fixing roll, 30.
...Hishidai.

Claims (1)

[Claims] 1. A plate fixing mechanism that wraps and fixes an electrostatic printing master plate at a fixed position on a metal drum, a toner development mechanism that develops the charged master plate with toner, and a toner development mechanism that develops the developed toner image onto a conductive rubber transfer roll. A reverse image adjustment mechanism that temporarily holds a reverse image of the toner image by applying an electric field of a polarity different from that of the toner image, and a corona charging mechanism that transfers the toner image on the conductive rubber transfer roll to a transfer object. An electrostatic offset printing machine comprising a transfer mechanism, a fixing mechanism for fixing a transfer object to which a toner image has been transferred, and an ejection mechanism for ejecting the fixed transfer object to a transfer object discharge section.