Porous gas-permeable substructure layer of a thin gas impervious layer for use as functional component in high temperature fuel cells

Porous gas-permeable sub-structure has a smooth surface formed by a sealed edge zone. The edge zone and a support structure surrounding the zone is produced from a uniform material mixture of sinterable particles. The porosity of the support structure is 30 vol.%. The pore size of the edge zone is 10 mu m. An Independent claim is also included for an electrochemically active element containing the sub-structure.