| 摘要 |
1517344 Pipes B LAGERCRANTZ 20 Nov 1975 [5 June 1975] 24326/75 Heading F2P [Also in Division B5] A tube 10 of plastics material has one or more longitudinal strips 12 on the outer surface thereof. The tube is formed of a cross-linked polyolefinic material, polyvinylchloride, polybutylene, polypropylene or polyethylene, whilst the strips are thermoplastics material such as polyethylene or polypropylene. The strips may be coloured and may have surface striations or projections. The method of manufacture is by extruding the tube, from extruder 20, contacting a substantially continuous length of thermoplastics strip 25 with the tube, the tube and/or the strip being at a temperature above its softening point, pressing the strip and the tube together, by platen 23, to cause or allow fusion between the tube and the strip, and thereafter cooling the tube. Preferably the strip is at room temperature and the tube is at a temperature of at least 200‹ C. |
