Patent ID: 6495087
Filing Date: 2002-12-17
Classification: B29C,B29K,B29L,B32B

Abstract:
A preparation of thermal contraction sleeve consisting of a thermal shrinkable fabric sheet and a thermal shrinkable matrix sheet, comprising the steps of:a) exposing polyethylene fibers elongated by 850%Ëœ1,200% to a radiation of 2.5Ëœ3.5 Mrads, thus cross-linking the polyethylene fibers; b) exposing a first surface of a fabric sheet made of said polyethylene fibers to a voltage of 20,000Ëœ25,000 V, thus modifying the first surface of the fabric sheet, and forming a first matrix sheet, melt-extruded from a first extrusion die, on said modified first surface of the fabric sheet, and setting the first matrix sheet on the modified surface of the fabric sheet by allowing the fabric sheet with the first matrix sheet to pass through a nip between a first elastic roller and a first cooling roller; c) modifying a second surface of said fabric sheet through the same process as that of step â€œbâ€  and forming a second matrix sheet, melt-extruded from a second extrusion die, on said modified second surface of the fabric sheet and setting the second matrix sheet on the modified second surface of the fabric sheet by allowing the fabric sheet to pass through a nip between a second elastic roller and a second cooling roller, thus forming a fabric-matrix layered body; and exposing the first and second matrix sheets of said fabric-matrix layered body to a radiation of 2.5Ëœ3.5 Mrads, thus cross-linking said matrix sheets.