Process for the production of multiple layer gas diffusion electrodes

Claim 1

PROCESS FOR THE PRODUCTION OF A POROUS MULTIPLE LAYER GAS DIFFUSION ELECTRODE STRUCTURE, WHICH COMPRISES PRESSING TOGETHER, AT BETWEEN ABOUT 1000 AND 7000 KG./CM.2, AND THEN SINTERING, AT BETWEEN ABOUT 100 AND 1100*C., AT LEAST TWO ABUTTING INITIALLY DISCRETE METAL POWDER LAYERS TO FUSE THE INDIVIDUAL METAL POWDER PARTICLES OF EACH LAYER TOGETHER AND TO FUSE THE PARTICLES OF ONE LAYER WITH THE PARTICLES OF THE ADJACENT LAYER, SUCH FUSION TAKING PLACE SUBSTANTIALLY ONLY AT THE POINTS OF CONTACT BETWEEN THE PARTICLES, AT LEAST ONE OF THE LAYERS INITIALLY BEING IN THE FORM OF A SOLID TEMPORARY THIN FLAT STRUCTURE WITH THE METAL POWDER PARTICLES THEREOF BEING MAINTAINED IN FIXED DISPOSITION BY A HEAT-DECOMPOSABLE BINDER MATERIAL, AND RECOVERING THE LAYERS AS A COMPOSITE POROUS MULTIPLE LAYR ELECTRODE STRUCTURE SUBSTANTIALLY FREE FROM THE BINDER MATERIAL, WITH THE PARTICLES FUSED TO ONE ANOTHER THROUGHOUT THE ELECTRODE STRUCTURE.