| 摘要 |
1,085,765. Electrically treating extruded tubing. DEUTSCHE VETAPHONE GESELLSCHAFT FUR ELEKTRONISCHE GERATE m.b.H. May 24, 1965 [May 23, 1964], No. 21846/65. Heading B5A. [Also in Divisions B6 and H1] A hollow tube 6 of a plastics material such as polyethylene is subjected to an electric field between electrodes 2, 9 immediately after leaving the head 1 of an extrusion machine in order to increase the adhesion of printing ink to the outer surface of the tube. The inner electrode 2 may be the core of the extrusion head or an extension thereof. The outer electrode is spaced from the outer surface of the tube 6 so as to expose it to electrical discharges and may be in the form of a stationary annular member, Fig. 1 (not shown) or may comprise a plurality of planar members 9 projecting radially inwardly of a rotatable insulating support member 8, said member 8 being rotated by a friction wheel 11. The drive for the rotatable support may be replaced by a lifting magnet if the tube is to be partially pre-treated. The outer electrode(s) may be of a non-metallic material such as graphite or carbon. |
