Method of producing shrink sleeves for cable connections and junctions

A shrink sleeve for application to an electrical cable comprising:

• a layer of a thermoplastic synthetic resin shrinkable at a high temperature, said layer forming a shrinkable sleeve for sealing cable connections and branches;
• an adhesive layer coated on an entire internal surface of said sleeve and comprising:
• a layer of a cross-linkable hot melt adhesive lined with said entire internal surface of the sleeve, and;
• a layer of a perforated carrier synthetic resin containing a cross linker on said layer of said hot melt adhesive, said layer of said perforated carrier resin being pressed into said layer of said hot melt adhesive which flows into said perforated synthetic resin at a low temperature lower than said high temperature, flow of the hot melt adhesive being arrested at the high temperature upon cross linking of the layer of hot adhesive by said layer of the cross linker.

A method of using a shrink sleeve of a thermoplastic synthetic resin for cable connections and branches, comprising the steps of:

• forming a layer of said thermoplastic synthetic resin shrinkable at a high temperature, thereby providing a shrink sleeve;
• forming an adhesive layer on an entire internal surface of said sleeve by:
• lining a layer of a cross-linkable hot melt adhesive over said entire internal surface of the sleeve,
• thereafter providing a layer of a perforated carrier synthetic resin containing a cross linker over said layer of hot melt adhesive, and
• pressing said layer of the carrier synthetic resin into said layer of hot melt adhesive at a low temperature lower than said high temperature, thereby providing a hot adhesive flow into said layer of the carrier synthetic resin;
• and
• hereafter heating the sleeve at said high temperature to cross link the layer of hot adhesive by said layer of the carrier resin, thereby arresting the flow of said adhesive upon shrinking of the sleeve at the high temperature.

A shrink sleeve for application to an electrical cable comprising:

• a sheath of a thermally shrinkable synthetic resin;
• a layer of a hot melt adhesive on an inner surface of said sheath;
• and
• a cross-linking agent on said hot melt adhesive thermally activatable upon heating of said sleeve to shrink said sleeve to effect cross linking of said hot melt adhesive, said linking agent is selected from the group which consists of:
• 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane,
• 2,5-dimethyl-2,5-di-(t-butylperoxy)hexen-3,
• 2,5-dimethyl-2,5-di-(t-butylperoxy)hexane-3,
• .alpha.,.alpha.'-di(t-butylperoxy)diisopropybenzene,
• dicumylperoxide (bis(1-methyl-1-phenylethyl)peroxide,
• ethyl-3,3-di(t-butylperoxy)butyrate,
• ethyl-3,3-di(t-amylperoxy)butyrate,
• n-butyl-4,4-di(butylperoxy)valerate, or
• 1,1-di(t-butylperoxy)cyclohane,
• said cross-linking agent being provided in a synthetic resin carrier having a softening temperature below a temperature at which said cross linking agent is activated and being incorporated into a synthetic resin in an open work structure pressed into said hot melt adhesive.