New aspects of thin polyimide foils

A series of thin polyimide foils (16-115 μg/cm2) were prepared in a glove-box under a controlled, dry atmosphere. Strengths, as defined by the Chen rupture coefficient, were measured and compared with previously published values for foils prepared at about 25% relative humidity and were found to be about 50% higher over the whole thickness range investigated. The use of a glove-box therefore permits the preparation of stronger foils, independent of weather conditions (relative humidity) and with the added advantage of dust-free conditions. The resistivity of thin carbon layers on polyimide foils was measured for carbon deposits prepared by electron beam evaporation and by laser plasma ablation. The use of such carbon coated polyimide foils as the cathode in an electrodeposition process was investigated. (orig.)