FIELD: fiber-optic cables. SUBSTANCE: cable has water-soluble polymeric material capable of swelling under effect of water. Water spread in this cable is blocked due to integrated effect of water-soluble material swelling and formation of aqueous solution of mentioned material which has predetermined viscosity to prevent residual water flow. Water-soluble material is chosen from polyacrylamide modified by polyvinyl alcohol, vinyl alcohol/vinyl acetate copolymers, polyvinylpyrrolidone, and their mixtures; best material is vinyl alcohol/vinyl acetate copolymer. Material can be extruded to form tubular parts for enclosing optical fibers, such as double-layer tubular parts where inner layer is made of water-soluble material and outer one, of standard polymer of PE, PP, or PBT type. EFFECT: enhanced resistance to radial ingress and longitudinal spread of water. 34 cl, 6 dwg, 7 tbl, 7 ex
