Telecommunication cables

Claim 2

AS AN ARTICLE OF MANUFACTURE, A TELECOMMUNICATION CABLE COMPRISING A MULTIPLICITY OF CONDUCTORS EACH AT LEAST IN PART INSULATED WITH PLASTICS MATERIAL HAVING AN ANTI-OXIDANT THEREIN AND A WATER-PROOF SHEATH, THE INTERSTICES BETWEEN THE INSULATED CONDUCTORS AND BETWEEN THE CONDUCTORS AND THE WATER-PROOF SHEATH BEING FILLED WITH A WATER-IMPERMEABLE MEDIUM WHICH WILL NOT DRAIN UNDER THE INFLUENCE OF GRAVITY OR SUCH HYDROSTATIC PRESSURE AS MAY ARISE IN THE EVENT OF DAMAGE TO THE CABLE SHEATH BUT WHICH WILL PERMIT RELATIVE SLIDING MOVEMENT OF THE INSULATED CONDUCTORS OVER ONE ANOTHER DURING SUCH BENDING OF THE CABLE AS OCCURS DURING MANUFACTURE AND INSTALLATION OF THE CABLE AND WHICH COMPRISES, AS AN ESSENTIAL INGREDIENT, AT LEAST ONE SYNTHETIC POLYMERIC MATERIAL SYNTHESISED FROM PETROLEUM PRODUCTS AND, AS ANOTHER INGREDIENT, AT LEAST ONE OF HYDROCARBON WAX, A HYDROCARBON OIL AND A MIXTURE OF A HYDROCARBON WAX AND OIL, WHEREIN SUFFICIENT OF AT LEAST ONE ANTI-OXIDANT IS INCORPORATED IN THE WATER-IMPERMEABLE MEDIUM THAT, WHILE THE CABLE IS IN SERVICE AND ANTI-OXIDANT FROM THE PLASTICS INSULATION OF THE CONDUCTORS IS TENDING TO PERMEATE INTO THE WATERIMPERMEABLE MEDIUM, THE ANTI-OXIDANT INCORPORATED IN SAID WATER-IMPERMEABLE MEDIUM WILL TEND TO PERMEATE INTO THE PLASTICS INSULATION OF THE CONDUCTORS THEREBY SUBSTANTIALLY TO COMPENSATE FOR LOSS OF ANTI-OXIDANT FROM THE CONDUCTOR INSULATION INTO THE WATER-IMPERMEABLE MEDIUM.

Claim 3

A telecommunication cable as claimed in claim 1, wherein the cable is of the unit type and the interstices between the insulated conductors of each group of conductors and between the conductors and a water-impermeable covering therefor are filled with the water-impermeable medium containing anti-oxidant.

Claim 4

A telecommunication cable as claimed in claim 1, wherein the proportion of anti-oxidant in the filling medium does not exceed 0.5 percent by weight of filling medium.

Claim 5

A telecommunication cable as claimed in claim 1, in which the conductor insulation is of polyethylene, wherein the proportion of anti-oxidant in the filling medium lies within the range of 0.1 to 0.2 percent by weight of filling medium.

Claim 6

A telecommunication cable as claimed in claim 1, wherein the anti-oxidant is 2:6 - ditertiary butyl-4-methylphenol.

Claim 7

A telecommunication cable as claimed in claim 1, wherein the anti-oxidant is 2:2'' - methylenebis - (6 - Alpha -methylcyclohexyl - 4 - methylphenol).

Claim 8

A telecommunication cable as claimed in claim 1, wherein the anti-oxidant is 4:4'' - thiobis - (6 - tertiary butyl - 3 -methylphenol).

Claim 9

A telecommunication cable as claimed in claim 1, wherein the anti-oxidant comprise a mixture of tris - (2 - methyl - 4 -hydroxy - 5 - tertiary butylphenyl) butane and dilauryl - Beta Beta 1 - thiodipropionate in the ratio from 1:1 to 1:3 by weight is incorporated in the water-impermeable medium.

Claim 10

As an article of manufacture, a telecommunication cable comprising a multiplicity of conductors each having a dielectric of plastics material of cellular form having an anti-oxidant therein and a water-proof sheath, the interstices between the insulated conductors and between the conductors and the water-proof sheath being filled with a water-impermeable medium which will not drain under the influence of gravity or such hydrostatic pressure as may arise in the event of damage to the cable sheath but which will permit relative sliding movement of the cellular plastics insulated conductors over one another during such bending of the cable as occurs during manufacture and installation of the cable and which comprises, as an essential ingredient, at least one synthetic Polymeric material synthesised from petroleum products and, as another ingredient, at least one of a hydrocarbon wax, a hydrocarbon oil and a mixture of a hydrocarbon wax and oil, wherein sufficient of at least one anti-oxidant is incorporated in the water-impermeable medium that, while the cable is in service and anti-oxidant from the cellular plastics insulation of the conductors is tending to permeate into the water-impermeable medium, the anti-oxidant incorporated in said water-impermeable medium will tend to permeate into the cellular plastics dielectric of the conductors thereby substantially to compensate for loss of anti-oxidant from the conductor insulation into the water-impermeable medium.

Claim 11

As an article of manufacture, a telecommunication cable comprising a multiplicity of conductors each having a dielectric of plastics material of cellular form having an anti-oxidant therein and a water-proof sheath, the interstices between the insulated conductors and between the conductors and the water-proof sheath being filled with a water-impermeable medium which will not drain under the influence of gravity or such hydrostatic pressure as may arise in the event of damage to the cable sheath but which will permit relative sliding movement of the cellular plastics insulated conductors over one another during such bending of the cable as occurs during manufacture and installation of the cable and which comprises, as an essential ingredient, at least one synthetic Polymeric material synthesised from petroleum products and, as another ingredient, at least one of a hydrocarbon wax, a hydrocarbon oil and a mixture of a hydrocarbon wax and oil, wherein sufficient of at least one anti-oxidant is incorporated in the water-impermeable medium that, while the cable is in service and anti-oxidant from the cellular plastics insulation of the conductors is tending to permeate into the water-impermeable medium, the anti-oxidant incorporated in said water-impermeable medium will tend to permeate into the cellular plastics dielectric of the conductors thereby substantially to compensate for loss of anti-oxidant from the conductor insulation into the water-impermeable medium.

Claim 12

As an article of manufacture, a telecommunication cable comprising a multiplicity of conductors each at least in part insulated with plastics material having an anti-oxidant therein and a water-proof sheath, the interstices between the insulated conductors and between the conductors and the water-proof sheath being filled with a water-impermeable medium which will not drain under the influence of gravity of such hydrostatic pressure as may arise in the event of damage to the cable sheath but which will permit relative sliding movement of the insulated conductors over one another during such bending of the cable as occurs during manufacture and installation of the cable and which comprises, as an essential ingredient, at least one synthetic polymeric material synthesised from petroleum products and, as another ingredient, petroleum jelly, wherein sufficient of at least one anti-oxidant is incorporated in the water-impermeable medium that, while the cable is in service and anti-oxidant from the plastics insulation of the conductors is tending to permeate into the water-impermeable medium, the anti-oxidant incorporated in said water-impermeable medium will tend to permeate into the plastics insulation of the conductors thereby substantially to compensate for loss of anti-oxidant from the conductor insulation into the water-impermeable medium.

Claim 13

As an article of manufacture, a telecommunication cable comprising a multiplicity of conductors each at least in part insulated with plastics material having an anti-oxidant therein and a water-proof sheath, the interstices between the insulated conductors and between the conductors and the water-proof sheath being filled with a water-impermeable medium which will not drain under the influence of gravity of such hydrostatic pressure as may arise in the event of damage to the cable sheath but which will permit relative sliding movement of the insulated conductors over one another during such bending of the cable as occurs during manufacture and installation of the cable and which comprises, as an essential ingredient, at least one synthetic polymeric material synthesised from petroleum products and, as another ingredient, petroleum jelly, wherein sufficient of at least one anti-oxidant is incorporated in the water-impermeable medium that, while the cable is in service and anti-oxidant from the plastics insulation of the conductors is tending to permeate into the water-impermeable medium, the anti-oxidant incorporated in said water-impermeable medium will tend to permeate into the plastics insulation of the conductors thereby substantially to compensate for loss of anti-oxidant from the conductor insulation into the water-impermeable medium.