Abstract: The laser-markable sheathing comprises a carbon-blacked inner PE layer with a soot proportion of 2.5±0.5% by weight and an outer PE layer 0.05 to 0.2 mm thick. The outer PE layer completely absorbs the laser radiation (?=532 nm) used for the marking, and the inner layer beneath it remains intact. A largely carbon-free, foamlike structure which greatly scatters incident light serves as an abrasion-proof marking. The sheathing is suitable for cable cores, fiber-optic cable strands, and the like.

Abstract: An apparatus and process for obtaining the desired outside diameter for a tension-resistant core element, which includes assembling mixed filaments containing glass fibers and thermoplastic fibers, heating the bundle of mixed filaments to melt the thermoplastic fibers to form a matrix with the glass fibers embedded therein, then extruding an outer covering of the desired outside diameter for the core element onto the bundle. If desired, the melted bundle can be passed through a shaping device, which is preferably heated prior to extruding the coating thereon, and, subsequent to extruding, the extruded coating and bundle are cooled in the cooling device before being wound on a take-up drum or entering a stranding device for having communication elements stranded thereon.

Abstract: The submarine optical cable has a basic structure which does not prevent rising up. Therefore, the cable is provided with at least one additional element which has a specific weight that is selected to be greater than 2.1 g/cm.sup.3 and prevents the rising up of the cable.