Manufacture of fibrous web structures
AssigneeConwed Corporation
InventorDonald E. Wiegand
Life of this patent
Estimating the term…
Abstract
Fibrous web structures in which the individual fibers are uniformly felted in random orientation are produced by projecting a stream of solids suspended in air toward a moving porous collection surface. The fibers are maintained in a controlled condition uniformly dispersed in air during transit from the nozzle to the porous collecting surface and before the stream of air has spread to the point of disrupting the uniform fiber dispersion, the fibers are felted and collected on the porous support while air is continuously passed through the support to insure no gravity free fall of fibers. Liquid or dry adhesive binders may be incorporated into the structure at any convenient stage of the process but preferably before the web structure is formed on the moving support.
Claims5
The method of forming a uniform felted fibrous structure by projecting an air fiber stream of fibers from a nozzle for collection on a collecting screen having edges comprising:
- a. selecting cellulosic type fibers having a length of 0.25 inch or less;
- b. forming a relatively dilute air suspension of substantially individualized fibers in which at least about one-half of the fibers are the said selected fibers having a length of 0.25 inch or less;
- c. subsequently concentrating said air-fiber suspension by removing air therefrom;
- d. selecting a nozzle configuration for projecting said suspension as a jet stream;
- e. oscillating said nozzle;
- f. projecting said suspension of fibers from said selected nozzle as a jet stream at a linear velocity of at least 2,000 feet per minute toward the collectng screen and without said suspension of fibers passing over the edges of the collecting screen;
- g. applying a suction to the opposite side of said screen;
- h. correlating the selected nozzle configuration to the distance betweeen the nozzle outlet and screen;
- i. positioning the screen at a selected correlated distance from the nozzle to maintain the integrity of said stream and the dispersion of said fibers as individual fibers without the formation of clots during transit from the nozzle to the scrren area;
- and
- j. collecting the fibers of said stream on said screen to form a felted mat.
Dependencies are inferred from the claim text.