Electromagnetic Printing: A New Application Technology (1)

Electromagnetic printing was the main application technology for the Nipson press. It was invented by Bull in 1980 and commercialized in 1984. This printing technology consists of an array of tiny electromagnetic recording write heads, which produces a magnetic latent image on the surface of a hard metal roller. After that, it is developed with a magnetic toner. The toner absorbs ink on the magnetic latent image, and the ink is pressurized. After being transferred to the paper surface, it is heat-fixed to create a fixed image. This printing technology is a brand-new application technology for the printing industry.

First, the printing engine

The printing engine is composed of several simple and reliable subsystems. The basic body of the engine is a roller. It is based on hard metal and is similar to the application of photocopying technology. The other subsystem is similar in function to other non-contact technologies, but its structure is actually quite different. The surface structure of the printing cylinder is a layer of electromagnetic hard layer, and the electromagnetic is placed on the magnetically soft material with a magnetic strength of about 500oerst.

In fact, the mechanical resistance of the roller surface is quite strong without the use of soft coating. The life of the roller is more than 15 million feet long, and the electromagnetic printing can match different image lengths to meet the needs of printing applications without having to change the roller. Diameter, just increase the speed of the print engine.

The magnetic afterimage on the drum can be degaussed by the elimination bar each time it is rotated so that the drum can continue to receive new magnetic images.

Second, recording head

The image recording station contains an array of electromagnetic recording write heads, which are axially parallel to the drum. The processing procedure is similar to that of disk drives in computers, and is specially designed for electromagnetic printing applications. The first-generation recording heads used in the early days were used for vertical recording. During operation, the coils did not change in succession. Therefore, lower drive currents could be used in the range of 100-150 microamperes, resulting in higher magnetic efficiency. Can make the lateral density higher. It is impossible to use a traditional recording and writing structure. The recording head has a density of 240 poles per inch to form 336 poles per square. The development of electronics has made the recording heads of second-generation electromagnetic printers better, that is, in order to exceed the 240 dpi currently used, it is necessary to consider the use of collective recording and writing components, combined with standard silicon micro-electrochemical treatment and silicon electrochemical precipitation, so that magnetic collection With the electromagnetic microstructure becomes possible. The electromagnetic silicon recording head includes a one-inch square silicon chip. The recording head is a high-density array recording electromagnetic, which is positioned by a diode matrix on the chip. This new recording head allows for higher print quality, better stability, and higher speed recording heads.

The function of the electromagnetic recording and writing head is similar to the imaging effect of the reflected beam in the laser copier, the light emitting diode in electrophotography, or the ion card sandwiched in the electron beam.