The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1992
Filed:
Oct. 17, 1989
MAN Roland Druckmaschinen AG, Offenbach am Main, DE;
Abstract
To permit computer control, for example from a control console in a publisher's office, of the subject matter to be printed from a printing cylinder, the printing cylinder (3) has a layer of semiconductor material thereon, which, by doping, includes capacitative or inductive domains (15, 33), selectively energized in accordance with control from the computer through controllable electronic switches (16, 29), such as transistors formed in the semiconductor layer. Ferrofluidic ink can be attracted by charges onto capacitors formed in the semiconductor layer; the capacitors are charged, selectively, through the transistor electronic switches which are located and connected in a matrix. Packing densities of over 160 domains and switching elements per mm.sup.2 are readily possible and suitable, for example, for newspaper printing. Higher packing densities, for high quality printing, can be obtained by well known microelectronic technology. Further, depolarized regions are hydrophobic, and permit acceptance of printing ink, whereas polarized domains are hydrophilic, attract water, thereby permitting use of well known lithographic-type offset printing.