METHOD FOR PRODUCTION OF FILTERING MATERIAL Russian patent published in 1996 - IPC

FIELD: production of track membranes. SUBSTANCE: method involves imparting relative movement to bunch and film thus forming 0 to 90 deg angles in a three-dimensional space between the normal to the surface of irradiated area and bunch axis. Each irradiated section of film is irradiated by more than one pulse, and the angular speed of additional movement and duration of pulse are selected so that the relative angular displacement of the normal to the film surface and direction of bunch axis in the course of irradiation would be 0.6 d/D and the pulse period is selected so that the relative angular displacement of the normal to the film surface and direction of bunch axis within the time between adjacent pulses would be 2 d/D where d - average diameter of pores, microns; D - film thickness, microns. Polymeric film is transported through irradiation zone in a step-by-step mode. EFFECT: higher efficiency. 2 cl ,1 dwg