Abstract: Methods and associated apparatus are disclosed for use in mounting particles on and de-mounting particles from a substrate having an array of tacky and non-tacky areas. The particles can be either electrically conducting or electrically non-conducting. Selection of electrically conducting particles is preferred. The substrate having an array of tacky and non-tacky areas can either be electrically nonconducting (e.g., a dielectric substrate) or electrically-conducting. The methods involve use of first and second electrode plates with the substrate therebetween, the plates having applied thereto a direct current potential, which potential in preferred embodiments is reversed in polarity for a number N of cycles. Methods and articles are disclosed using an electrically conductive surface adjacent the tacky and non-tacky areas to minimize static buildup on the particles and tacky and non-tacky areas.

Abstract: This invention relates to flash spinning a plexifilamentary film-fibril strand and laying it down into sheet material including the step of subjecting the strand to an electrostatic charge. The invention is particularly focused on cleaning, and maintaining clean, the target plate of the electrostatic charging system by scrubbing or scouring the surface of the target plate with a highly abrasive brush moving at a relatively high speed. The target plate is selected to be abrasion resistant.