Abstract: A stretchable wadding with an apparent density of 0.005 to 0.05 g/cm.sup.3 formed from a web of crimp potential fibers bonded together and shrunk by drying is disclosed. In the preferred embodiment, crimp potential fibers are bonded to each other by spraying an adhesive onto both sides of the web, drying the adhesive, and shrinking the web by means of additional heat treatment to crimp the fibers.

Abstract: The disclosed method provides an electret filter having a permanent electrostatic charge and formed of polymer fibers having an intrinsic viscosity of 1.5 or less. Fibers of the requisite viscosity are formed into a non-woven fabric and fed, at room temperature, through a gap between a discharge electrode and a ground electrode while being tightly pressed against the ground electrode. The ground electrode preferrably presents a polished metal surface for contact with the web.

Abstract: A material with high thermal conductivity for insulating electronic parts is formed by exposure to a compressive shearing force of a compound containing 50 to 95% by volume heat conductive, inorganic powder and 5 to 50% by volume bonding agent. The bonding agent contains at least 0.2 to 30% by volume polytetrafluoroethylene (PTFE), preferably 1.0 to 20%, and synthetic rubber, where the volume ratio of rubber is 1/4 or more of the PTFE. The compressive shearing force fibrillates the PTFE and disperses the inorganic powder so that there is an even aggregation of heat conductive material. Other ingredients such as vulcanizing agents, vulcanizing accelerators, stabilizers, processing aids, flame retardents, coloring agents, and solvents may be added. The material may be reinforced with a woven or non-woven fabric or staple fibers.