摘要 |
PURPOSE:To obtain a heat-shrinkable sheet for connecting cables excellent in sealing property by a method wherein under heating the both sides of a stretched sheet, the neighborhood of each projection of the stretched sheet is crushed in the thickness direction and both sides are bent permanently and fixed to the outsides of the plastic sheet. CONSTITUTION:When a sheet 12B composed of a plastic sheet 10, the projections 11, 11 provided along both side edges of the outer surface of the plastic sheet and a fused layer 13 laid on the inner surface of the plastic sheet is stretched uniaxially in the width direction, the heat shrinkability is given to the plastic sheet to foam a stretched sheet 12C. While heating both sides only of the stretched sheet 12C, the thicker area near each projection 11, 11 is crushed in the arrow direction to give a nearly uniform thickness to the areas except the projections 11, 11. Each side of the stretched sheet 12C is folded outside in a heating state and cooled to set the folded lines permanently after the elapse of predetermined time to prepare a heat shrinkable sheet 12D. |