Back to results
US 3,952,124 AGranted
Back-to-back transition web and method of making said
AssigneeJohnson & Johnson
InventorFrederick K. Mesek
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeJohnson & Johnson
InventorFrederick K. Mesek
Estimating the term…
A method for producing a multi-layer web, and the web produced thereby, are disclosed. The nonwoven web consists of two half-thickness portions laminated to each other. A first half-thickness portion is characterized by a given overall concentration of long and short fibers and has one face enriched in long fibers above the overall concentration and the other face enriched in short fibers above the overall concentration. The concentrations of long and short fibers decrease substantially uniformly from the enriched faces to form a transition region within the half-thickness portion. The second half-thickness portion is bonded to the short fiber-enriched face of the first half-thickness portion and has an outer face (opposite the bonded face) of substantial structural integrity as compared to the short length fiber-enriched face of the first half-thickness portion. In the preferred embodiment, the second half-thickness portion is similar to the first half-thickness portion and bonded in mirror image relationship thereto. The method produces two half-thickness portions which are bonded together to form a multi-layer web. A first half-thickness portion is produced by feeding long and short fibers at given concentrations to individualizing means. The individualized fibers are deposited on a moving foraminous belt to produce a half-thickness portion enriched with long fibers at one face and short fibers at the other face and having a transition of fiber concentrations between the faces. A second half-thickness portion having at least an outer face with greater structural integrity than the short fiber-enriched face of the first half-thickness portion is produced by air-laying techniques. The second half-thickness portion is bonded with its outer face opposite the pulp-enriched face of the first half-thickness.
A nonwoven web comprising:
A through-bonded nonwoven web comprising two half-thickness portions laminated to each other, at least one half-thickness portion being characterized by a given overall concentration of long fibers and short fibers, said half-thickness portion having long fibers in excess of said given overall concentration at one major face and having short fibers in excess of said given overall concentration at the other major face, and having a transition of fiber concentrations between said major faces, and a second half-thickness portion through-bonded to the face of said first half-thickness portion wherein the concentration of short length fibers is in excess of said given overall concentrations, said second half-thickness portion being selected from the group consisting of (a) portions characterized by a uniform blend of long and short fibers throughout their thickness, (b) portions comprised entirely of long fibers, (c) portions comprised entirely of short fibers, (d) portions characterized by a predominance of short fibers at their inner major faces, a predominance of long fibers at their outer major faces and a transition of fiber concentrations between the faces, and (e) portions characterized by a layer of short fibers defining their inner major faces and a layer of long fibers defining their outer major faces and having sharp interfaces between adjacent layers.
A method of forming a multi-layer nonwoven web containing long and short length fibers from two half-thickness portions comprising the steps of:
Dependencies are inferred from the claim text.