Abstract: The present invention provides a process for electrolytic printing using an improved electrode. The electrode has a region which is an oxide of a metal from the group of ruthenium, iridium, platinum or an alloy thereof. The oxide region is at the extremity of the electrode which during the printing is in close proximity to the printing medium. This oxide region provides an increase in wear resistance of about two orders of magnitude over non-oxidized electrodes. Method for fabricating the described electrode is also set forth.

Abstract: An electrochromic printhead and a method of construction thereof in which the printhead is fabricated from an array of spaced, precisely positioned, small glass tubes. The array of glass tubes defines an array of cylindrical apertures extending through the printhead to form a printing pattern at a printing surface. Each cylindrical aperture has a conductor therein as an active electrode, which defines one dot of an array or matrix of dots possibly formed by the electrochromic printer. An additional conductor is provided as a reference electrode, such that a voltage may be applied between selected active electrodes and the reference electrode to define a particular printing pattern. Electrode wear is substantially eliminated by applying a coating of rutenium oxide crystals on each active electrode at the printing surface. In one disclosed embodiment, each active electrode is formed by a conductive coating applied along the interior surface of each cylindrical aperture.

Abstract: By employing evaporation techniques, small particles, of the order of 100 A, of Fe.sub.3 O.sub.4 or FeO having relatively high magnetic moments can be fabricated.