摘要 |
A method of producing a shaped fibrous fabric structure is similar to that described in the parent application, in that a continuous filament sheet is subjected to a needle punching action, segments are cut from the sheet and these segments are assembled to form an annulus, and then subjected to rotary motion under a reciprocating needling head and continuing to add segments to build up a stack of layers while at the same time continuing the needling action, and lowering the base of the stack relatively to the needling head. However, in a final step, one or more layers of segments are added to the top of the stack, and these are needled into the stack without lowering the stack. Furthermore, these additional layers are preferably made entirely of stapled fibers. Some or all of the layers of segments below the final layers may themselves be made of duplex material comprising continuous filament on which is laid a web of stapled fibers before the duplex material is produced by needling the stapled web to the continuous filaments.
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