| 摘要 |
A new fiber-forming method, and related apparatus, and webs prepared by the new method and apparatus are taught. In the new method a) a stream of filaments is extruded from a die of known width and thickness; b) the stream of extruded filaments is directed through a processing chamber that is defined by two narrowly separated walls that are parallel to one another, parallel to said width of the die, and parallel to the longitudinal axis of the stream of extruded filaments; c) the stream of filaments passed through the processing chamber is intercepted on a collector where the filaments are collected as a nonwoven fibrous web; and d) a spacing between the walls of the processing chamber is selected that causes the stream of extruded filaments to spread before it reaches the collector and be collected as a web significantly wider in width than the die. Generally the increase in width is sufficient to be economically significant, e.g., to reduce costs of web manufacture. Such economic benefit can occur in widths that are 50, 100 or 200 or more millimeters greater in width than the width of the die. Preferably, the collected web has a width at least 50 percent greater than said width of the die. The processing chamber is preferably open to the ambient environment at its longitudinal sides to allow pressure within the processing chamber to push the stream of filaments outwardly toward the longitudinal sides of the chamber.
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