| 摘要 |
A heat-recoverable member has a coating of a viscose flowable material applied to the surface and an anti-tack coating applied over at least a part of the surface of the said material not in contact with said member the coating being such that at the recovery temperature of the member it will dissolve in the material. The member may possess the property of elastic memory and may be made of a cross-linked polymer which may have been cross-linked by the chemical means or by irradiation e.g. u.v. radiation. The polymer may be a polyethylene or a co-polymer of ethylene and an alkyl acrylate, tetrafluoroethylene or vinyl polymers such as p.v.c. The member may be tubular and may be preformed to expand or contract on recovery the interior or exterior surface or both may have the flowable viscous material applied thereto. The member may be a tape which may be wrapped around a body to be protected. The anti-tacke coating preferably covers the whole of the surface of the flowable viscous material. The coating may be of wax of m.p. 50-90 DEG C. and may comprise carnauba wax, wax-rosin mixtures, such as bees wax-rosin mixtures, ouricury, candelilla and palm waxes. The flowable viscous material has a viscosity at room temperature sufficiently high to enable it, when contacted with the surface of the heat recoverable member, to remain in contact under normal gravitational forces. Materials having a viscosity of up to 1013 centipoises at 25 DEG C. have been found suitable. Suitable materials are of a mastic type or a thixotropic, and it may be substantially non-crystalline such as a silicone or hydrocarbon grease, which may be rendered electrically conductive by dispersing therein finely divided particles of a conductive material such as graphite. |
