SU1137436A1 - Method of forming reference electrostatic picture on dielectric medium - Google Patents

Abstract

A METHOD OF FORMING A REFERENCE ELECTROSTATIC IMAGE ON A DIELECTRIC MEDIA, including the deposition of electrical charges on its surface through a metal stencil, and so that, in order to measure metrological accuracy and speed of drawing, the pattern is drawn and the pattern is formed and the image is drawn with a pattern of metrical accuracy and speed of drawing. portions of the carrier charge the metal stencil with a constant charge time, 2–3 times longer than the constant charge time of the open portions of the dielectric carrier. & 9 Lai 00 9)

Description

1 The invention relates to electrography, in particular, to the formation of a reference electrostatic image on a non-photosensitive surface for testing developing structures (electrographic manufacturers), devices and methods of development. A known method of forming a reference electrostatic image on a dielectric carrier involves the deposition of electrical charges on its surface through a metal stencil ij. The disadvantages of this method are the narrow metrological accuracy and speed of image formation on a dielectric surface. The purpose of the invention is to improve the metrological accuracy and speed of image formation on the dielectric surface, which can be used to check and test the electrographic displays of compositions, as well as to check the functioning of the electrophotographic units and devices. This goal is achieved by the fact that according to the method of forming an electrostatic image on a dielectric carrier, simultaneously with the charging of the open areas of the carrier, a metal stencil is charged with a constant charging time of 2–3 times longer constant charging time. open portions of the dielectric carrier. The drawing shows a diagram of the device for implementing the method. The diagram shows the dielectric layer I on a conductive substrate 2 ion generator, for example, a radioactive particle emitter, a metal stencil 3, a control electrode 4, a dielectric film 5 with a conductive coating. The method is carried out as follows. A hidden electrostatic image is formed on a metallized lavsan film 1, 20 microns thick. The conductor coating is grounded, and a metal stencil 3 of copper foil 50 µm thick is applied on its surface in which parallel 62 strokes are etched with a spatial frequency of 1 to 8 mm. A metal control is installed at a distance of 20 Mm from the dielectric layer. the electrode is a metal grid to which a voltage is applied, the magnitude of which is exactly equal to the voltage to which it is necessary to charge the open portions of the dielectric layer. Behind the grid control electrode 4 there is an ion generator, made in the form of a plate, with a radioactive isotope of plutonium-239, emitting rays that ionize the air gap between the control electrode 4 and the dielectric layer 1. In an electric field created by the application of voltage between the conductive substrate of the dielectric layer 1 and the control electrode 4, the metal stencil-dielectric layer system begins to charge. The current in the air gap flows until the field strength at each point of this gap becomes zero, i.e. until the metal stencil 3 and the open portions of the dielectric layer 1 are charged to the potential of the control electrode 4.. Had a metal electrode. was connected directly to the control electrode 4 (if the voltage on the metal electrode increased much faster than on the dielectric layer), then the dielectric layer in the slots of the stencil would be charged very slowly, especially in narrow slots. This is due to the fact that the field of the metal stencil, extending up to the control electrode 4, prevents the directional movement of the charged particles to the narrow slits of the metal stencil 3, under which there are charged portions of the dielectric layer 1. As is known, the field electrostatic image of high spatial frequency exists only in close proximity to the surface, therefore, only ions generated in the immediate vicinity of the surface dielectric areas, and their number there is very small.

3

If the metal stencil is insulated (from both the ground and the control electrode) and the metal stencil — the dielectric layer is charged during system charging — the dielectric layer with the same velocity as the dielectric layer in the slits, then as the stencil voltage approaches the metal stencil field starts to shield the charging portions of the dielectric layer more strongly to the voltage of the targeting electrode, and the growth of charges on them slows down. In order to avoid this, it is necessary to slow down the rate of growth of the metal- stencil compared to the growth rate of the potential of the dielectric layer. The constant rise time of the charging voltage on the open portions of the dielectric layer should be at least 2 times longer than the constant charge time of the metal stencil, but more than 3 times more impractical because the overall slowdown does not pay off anymore. contrast of electrostatic imaging on narrow lines. In this case, a slowdown in the growth rate of the stencil potential has been achieved.

374364

due to the fact that along its perimeter was applied a dielectric film 5 with an external metallized coating, which was grounded V-thickness of the film 10 μm, and its area was equal to half the area of the metal stencil.

The rectangularity of the shape of the relief pattern was checked by a scanning electrometer with a mixing probe diameter of 70 µm. The width of the transition from the charged region to the uncharged region did not exceed 80 µm, i.e. determined by the aperture properties of the measuring probe system, and not by the electrostatic conversion itself.

The proposed method of forming an electrostatic image is used for metrological quality control of electrographic manufacturers. The use of this method has allowed a significant increase in the reliability of control of the compositions for electrography produced by the industrial type, since the methods for testing granularity, color, melting point, etc. a method was added for determining the integral criterion in electrophotography of the developer’s exhibiting and resolving power i.

Claims (1)

METHOD FOR FORMING A STANDARD ELECTROSTATIC IMAGE ON A DIELECTRIC MEDIA, including the deposition of electric charges on its surface through a metal stencil, characterized in that, in order to increase metrological accuracy and speed of image formation, the metal time is charged simultaneously with charging the exposed portions of the medium charging 2-3 times the constant charging time of open areas of the dielectric carrier. . . . '/ y //// /// 7 / lgg jpnHHwAi, .— I. w I ··. J