Flexible resistance-heating mat - has resistance paths formed on support foil by repeated screen printing and cross-connections made using silver paint

摘要

The mat has resistance paths formed on the underside of a support foil by screen printing. The required resistance is attained by repeated printing. The resistance areas are connected by strips of conducting silver paint. The contacts for the mains supply leads are made by self-adhesive copper paths fixed to the strips of silver paint. The resistance paths are covered by a plastic foil for protection and insulation. The insulating foil is fixed to the support foil by thermal or h.f. welding. The weld seam is around the edges of the foils or resistance areas and may be a single or double seam.