Water-soluble water-blocking element

摘要

The present invention provides optical-fiber communication cables with an improved water-blocking element that reduces or eliminates microbending caused by water-swellable particulate powders. In one embodiment, such water-swellable powders may be employed in conjunction with a smooth water-soluble carrier tape. In another embodiment, such water-swellable powders may embedded within a water-soluble binder. The water-blocking element is deployed within optical-fiber buffer tubes to water-block the buffer tubes and to minimize microbending that can occur when water-swellable particulate powders press against optical fibers.

主权项

1. An optical-fiber cable, comprising:
a plurality of optical fibers; a buffer tube enclosing said plurality of optical fibers, said buffer tube possessing a filling coefficient of at least about 0.20; a water-blocking element positioned between said plurality of optical fibers and said buffer tube, said water-blocking element comprising (i) a water-soluble, first carrier tape and (ii) water-swellable particulate powder bonded to said first carrier tape, wherein said water-blocking element at least partially surrounds said plurality of optical fibers, and wherein said first carrier tape is positioned adjacent to said plurality of optical fibers and said water-swellable powder is positioned opposite said plurality of optical fibers; and a polymeric cable jacket surrounding said buffer tube; wherein the optical-fiber cable complies with the GR-20-CORE temperature cycling requirement.