Cellulose Acetate Film Or Sheet Patents (Class 442/39)
  • Patent number: 6972151
    Abstract: A device for forming erasable images on a reusable medium, comprising: an erasing portion; and a writing portion; wherein the erasing portion comprises a separator for separating at least two layers of the reusable medium; and wherein the writing portion comprises automatic machine-driven pressure applicators for applying pressure but no ink to the reusable medium, thereby forming an image on the reusable medium.
    Type: Grant
    Filed: April 25, 2003
    Date of Patent: December 6, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Barry Bronson
  • Patent number: 6537930
    Abstract: A three-dimensional highly elastic film/non-woven composite having a fluid and air impervious core layer and a first and second consolidated layer. The consolidated layers have unidirectional and non-unidirectional fibers. The composite is formed by laminating the air and fluid impermeable elastic core layer between the two layers of consolidated non-wovens. The resulting composite stretches only in the cross-machine direction due to the unidirectional properties of the consolidated non-woven material. The layers are then point bonded or welded together. Preferably the layers are welded by passing the composite between an ultrasonic horn and an ultrasonic bond roll having raised areas for effecting the weld points. A thin inelastic membrane is formed at each of the weld points. The welded composite may then be pre-stretched to rupture the membranes, thereby creating apertures, which makes the composite permeable.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: March 25, 2003
    Assignee: Tredegar Film Products Corporation
    Inventors: Jeff A. Middlesworth, James W. Cree, Steve D. Bruce