| abstract |
Multilayer films are generated by dividing a first stream comprised of discrete layers of one or more materials into a plurality of branch streams (14,16,18,20), redirecting or repositioning (40) the branch streams, expanding (48) and contracting (54) the branch streams in a symmetrical fashion, and recombining (56) the branch streams to form a second stream having a greater number of discrete layers than the first stream. Alternatively, the branch streams are redirected or repositioned (64), recombined (68) to form a second stream having a greater number of discrete layers than the first stream, and the second stream expanded and contracted (66) in a symmetrical fashion. A gradient in, or other distribution of, thickness is provided by independently controlling (58,60) the flow rates of the branch streams. |