Process and device for producing piezoelectric and/or pyroelectric polyvinylidene fluoride films

摘要

For the continuous production of piezoelectric films, a polyvinylidene fluoride film is heated to a temperature below 135 DEG C and in the heated state simultaneously stretched between two roller pairs (13, 14; 21, 22) and subjected between electrodes (16, 17) to an electrical d.c. voltage field intensity of < 200 kV/cm. Subsequently the film (10) is wound under mechanical stress onto a winding bobbin (24) and annealed in an annealing oven (25) at approximately 130 DEG C for one to three hours. <IMAGE>