COMMUNICATION CABLE HAVING WATER-BLOCKING CAPABILITIES

A communication cable includes a core comprising at least one transmission medium and a sheath system which is disposed about the core. Means are disposed within the cable for preventing the longitudinal migration of water through the cable core, said means including both a hydrophilic material and a hydrophobic material in cooperative communication with each other. Specifically, a hydrophilic, waterabsorptive material is supported by a yarn which is helically wrapped about various sections of the communication core. In a copper cable, the waterabsorptive yarn may be wrapped about individual twisted pair conductors or a unit consisting of a plurality of twisted pair conductors or the cable core itself. In addition to the helically-wrapped, water-absorptive yarn, the cable of the present invention includes a hydrophobic, water-blocking material interdisposed to fill all voids and interstices within the communication core.