Electron curing of coatings and adhesives for wire and cable application

The curing of the high solvent content coatings used in thermal drying towers in the manufacture of enamelled wire constitutes a process of high specific energy consumption and significant atmospheric pollution. Experimental results are presented demonstrating the use of low energy electrons (150 keV) from a curtain type electron source for the uniform curing of solventless, free radical initiated enamels for this application. Thin film dosimetry is used to determine the irradiation uniformity and spectral quality of geometries suitable for single pass curing using one-sided or unilateral illumination of wire. Recent developments in the electron curing of laminating adhesives for the production of various paper, film and foil constructions are reviewed. The solvent free nature of these electron curable coatings and adhesives, coupled with the very low energy investment required for their cure (<10 cal/gm) and the almost instantaneous nature of the process, provide interesting possibilities for the manufacture of novel laminated construction for the wire and cable industry, or for insulation in general.