Abstract: In a method of manufacturing metallic or ceramic microparts using a three-dimensional body formed by first and second polymer fractions in a two-component injection molding process, wherein one of the polymer fractions comprises an electrically non-conductive polymer and the second an electrically conductive polymer, the polymer fraction used for the first injection molding step has a higher melting point than the polymer fraction used in the second injection molding step and the metal micropart is formed by galvanic deposition of a metal from an electrolyte and the ceramic micropart is formed by electrophoretic deposition of ceramic material from a ceramic suspension or colloid on the electrically conductive polymer fraction surface of a substrate surface of the interim body.

Abstract: In a process for producing microstructure components on a substrate which carries electronic microcircuits cooperating functionally with the microstructure components, a first layer of a plastic material which connects with the substrate is applied to the substrate and a second layer of a plastic material which includes a separating agent but which firmly connects with the first layer is applied to the first layer and a molding tool is then impressed into the second layer to form the desired microstructures or to form cavities into the plastic material, which, upon removal of the molding tool, are filled with a metal to form the desired microstructures on the substrate upon removal of the plastic material.

Abstract: An etching solution for etching away a metal layer from a substrate includes a hydrogen-containing compound that dissolves the metal layer while developing hydrogen; and a nitrosubstituted organic compound having a nitro group which is easily hydratable and which has at least a 1/3 nitro group equivalent per mole of the hydrogen developed by reaction between the hydrogen-containing compound and the metal layer until the metal layer is dissolved completely. A method for etching employs the etching solution into which the substrate is immersed. The process of preventing the release of hydrogen gas during the etching away of a metal layer from a substrate is taught and includes employing an etching solution containing one of an acid or a highly basic metal hydroxide; and adding to the etching solution an organic nitro compound which is soluble in water and which is easily hydratable.

Abstract: In a band-pass filter for electromagnetic radiation comprising a membrane having periodically arranged slot structure elements formed therein each consisting of at least three slots of equal length extending from a common point in radial symmetry, the membrane with the slot elements has a thickness of 33 to 500 .mu.m and the ratio of the membrane thickness to the grating constant which defines the periodic arrangement of the slot structure elements is larger than 1, thereby achieving optimum blocking characteristics for the filter.