METHOD OF MANUFACTURING POROUS FILTERS Russian patent published in 1997 - IPC

FIELD: filtration technics. SUBSTANCE: method involves local irradiation of initial film or plate with high-energy particle streams (radiation quanta, ions or electrons) followed by etching. According to invention, initial film or plate, prior to be irradiated, is covered with elastic resist layer, irradiation is followed by shrinkage operation, and etching is carried out in two steps: first with etching agent not affecting initial film or plate and etching through-holes in resist and then with etching agent not affecting elastic resist layer and etching through-holes in film or plate through holes in elastic resist layer. Shrinkage is performed before or after the first etching step. Before the first etching step, film or plate is additionally irradiated by high-energy particle streams through holes in elastic resist layer. As the latter, Langmuir film is utilized. EFFECT: intensified process. 6 cl, 1 dwg