Method of encapsulation
A method of encapsulating a substrate, especially a splice in a telephone cable, comprises (1) preparing an assembly comprising the substrate; an enclosure, preferably a heat-shrinkable enclosure, around the substrate; sealing material within the enclosure; and a heater within the enclosure; and (2) using said heater to change the viscosity of the sealing material. Preferably the heater is a PTC heater, especially one which is attached to thermoplastic sealing material in the form of a sheet or tape. In this way a desired distribution of heat through the assembly can be obtained so that extended heating times can be used.