Abstract: A check has first and second coatings one of which is electrically conductive and the other electrically non-conductive. The coatings are of contrasting colors and one of the coatings is electrically vaporizable for exposing the underlying coating during a "write" operation. The coatings may overlay a base material to form a three layer structure or the base material itself may function as one of the coatings of appropriate color and conductivity. The check is composed of at least two segments, a negotiable segment which may be fed back to a terminal device for a machine "read" operation. The memory segment may be formed into one or more memory parts on the negotiable segment, the stub portion and on the memory segment. One or more of these memory parts may be easily detached. The check described above combines uniquely with an input-output device which can read from it and write on it.

Abstract: A combination electrosensitive reader-printer able to perform both functions by sensing the condition of a recording medium in the read mode and by altering the condition of the recording medium in the printing mode. The change of mode is accomplished manually or automatically. The data to be read or written may be coded optically or digitally for interpretation by a processor. The recording medium is a metalized paper or similar material with an ink under or over lay. The resistivity, conductivity or capacitance change of the medium is sensed or altered by the reader-writer. Appropriate timing tracks and registration marks are normally placed to enable reading and writing by different devices. The styli for reading and writing normally are disposed in an array, straight or angled relative to the paper path. The styli have tips which are cylindrical, rectangular or oval in cross section. Control circuitry, including an analog to digital converter, control input to and output from the reader-printer.

Abstract: A business form has first and second coatings one of which is electrically conductive and the other is electrically non-conductive. The coatings are of contrasting colors and the second coating is electrically vaporizable for exposing the underlying coating when selectively removed during a "write" operation. The coatings may overlay a base material to form a three layer structure or the base material itself may function as one of the coatings of appropriate color and conductivity. A third coating overlays the second coating to form a matrix or array thereby organizing the document into sections. At the same time the third coating is put down, a light coat of a contrasting color can be overlaid the second coating. These two operations can be performed separately and in either order. The business form may be composed of first and second sections in which the second section may be a repeat of the basic information contained in the first section.