Abstract: The temperature in the sealed region of an electric lamp with a foil seal arrangement rises when the lamp is illuminated and the foil will oxidize due to the oxygen contained in the air if inappropriately protected. The oxidation leads to premature cracking in the foil, which renders further use of the lamp impossible. To prevent the foil from cracking due to oxidation and to permit the manufacture of a lamp with a long life, the foil is covered with lead oxide. For coating the foil with lead oxide, use is made of an aqueous solution of a lead compound, which decomposes on heating and produces lead oxide.