A novel blown microfiber web having a network of compacted high-density regions and pillowed low-density regions exhibits a unique combination of low density and good tensile strength and integrity. Such a web may be collected on a perforated screen so that microfibers deposited on the land area of the...http://www.google.de/patents/US4103058?utm_source=gb-gplus-sharePatent US4103058 - Pillowed web of blown microfibers
