| 摘要 |
PURPOSE:To easily and inexpensively obtain a resin bead capable of sufficiently withstanding soldering temp., by molding polyethylene into a tube body by an extrusion molding machine and crosslinking said tube body by irradiation with electron beam. CONSTITUTION:A stock material 1 is successively heated and melted in a cylinder through a usual extrusion molding proces, sent out to a hollow die, and emitted from said die in a tubular form, which is immediately stretched so as to obtain a desired fine cross-sectional shape and solidified under cooling. Next, the tubular body is crosslinked by irradiation with electron beam from an electron beam irradiation device to enhance the heat resistance of polyethylene and subsequently cut into a bead having a unit length. The obtained bead 4 can sufficiently withstand soldering temp. and, when the lead wire 3 of electronic parts 2 is clamped to a printed wiring board 1, the lead wire 3 is passed through the mount hole bored in the board and the bead 4 is externally fitted to the lead wire 3 to undergo soldering 5. Even if soldering 5 is applied, the bead shows stability with no thermal deformation. |
