Patent ID: 7528350

Claim:
A process for producing a connection structure which process comprises (1) providing (A) a PTC device including (i) a laminar polymer PTC element and (ii) a metal foil electrode disposed on a main surface of the laminar polymer PTC element, the metal foil electrode comprising at least two metal layers, one of which, the X-th layer, having a laser beam absorption of a % that is the lowest laser beam absorption of the metal layers of the metal foil electrode, and another of which, the first layer, having a laser beam absorption of b %, where b >a, and being located farthest from the laminar polymer PTC element, said X-th layer being positioned between the laminar polymer PTC element and the first layer, and (B) a metal lead element, and (2) electrically connecting the metal foil electrode to the metal lead element by laser welding.