Patents Assigned to Filtrona International Limited
  • Patent number: 8402977
    Abstract: A tobacco smoke filter which gives an acceptable vapor phase filtration and flavor delivery in the presence of a volatile flavorant (e.g. menthol), the filter containing activated carbon in which (1) pores of under 2 nm pore diameter (micropores) provide a pore volume of at most 0.3 cm3/g (NZ); and (2) (a) pores of 2 to 50 nm pore diameter (mesopores) provide a pore volume of at least 0.25 cm3/g (N2) and/or (b) pores of 7 to 50 nm diameter (larger mesopores) provide a pore volume of at least 0.12 cm3/g (Hg).
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: March 26, 2013
    Assignee: Filtrona International Limited
    Inventor: Anthony Denis McCormack
  • Patent number: 8083658
    Abstract: A method and apparatus for tobacco smoke filter production wherein a train of tobacco smoke filtering material, while being continuously advanced longitudinally, is gathered towards rod shape and then shaped to and secured in rod form, and wherein there is discontinuous pneumatic injection of particulate additive through an injector conduit laterally into the advancing gathering material to form separate additive pockets embedded in and spaced along the continuously produced rod.
    Type: Grant
    Filed: December 5, 2005
    Date of Patent: December 27, 2011
    Assignee: Filtrona International Limited
    Inventors: Serge Veluz, Alexis Louvet
  • Patent number: 7980250
    Abstract: A tobacco smoke filter which has a tar retention of at most 50% and comprises a relatively high draw resistance downstream filtering plug of at most 50% tar retention, a relatively low draw resistance upstream filter plug of at most 22% tar retention spaced longitudinally upstream therefrom, and a filter wrapper engaging around and joining the spaced plugs to define a cavity therebetween.
    Type: Grant
    Filed: October 13, 2003
    Date of Patent: July 19, 2011
    Assignee: Filtrona International Limited
    Inventor: Paul Francis Clarke
  • Patent number: 6174603
    Abstract: Bicomponent fibers comprising a core of a thermoplastic material, preferably polypropylene, and a sheath of a blend of the core-forming polymer and an ethylene-vinyl acetate copolymer are used to produce tobacco smoke filter elements which may be incorporated into tobacco smoke filter products such as filtered cigarettes. The addition of significant quantities of the core-forming material to the ethylene-vinyl acetate used to form the sheath avoids problems experienced heretofore in build-up of polymer in the forming dies using conventional filter-forming equipment Additionally, the blended sheath-forming polymer improves adhesion between the sheath and the core of the bicomponent fiber and, with the use of polypropylene, improves the hardness of the resultant tobacco smoke filter elements.
    Type: Grant
    Filed: August 25, 1999
    Date of Patent: January 16, 2001
    Assignee: Filtrona International Limited
    Inventor: Richard M. Berger
  • Patent number: 6103181
    Abstract: A fiber spinning device and process for manufacturing a web of fibers comprising a homogeneous mixture of fibers of different characteristics. Monocomponent fibers of different polymers can be extruded side-by-side from the same die system. Sheath/core bicomponent fibers can be alternated with monocomponent fibers formed of the same core polymer as used in the bicomponent fibers. Bicomponent fibers having a common core polymer and different sheath polymers can be extruded from alternate spinneret orifices in the same die plate. Multiple distribution plates are provided with surface grooves or depressions to direct polymer materials from independent sources to only selected spinneret openings in an array of spinneret openings while maintaining the polymers segregated from each other.
    Type: Grant
    Filed: February 17, 1999
    Date of Patent: August 15, 2000
    Assignee: Filtrona International Limited
    Inventor: Richard M. Berger
  • Patent number: 6026819
    Abstract: Bicomponent fibers comprising a core of a thermoplastic material, preferably polypropylene, and a sheath of a blend of the core-forming polymer and an ethylene-vinyl acetate copolymer are used to produce tobacco smoke filter elements which may be incorporated into tobacco smoke filter products such as filtered cigarettes. The addition of significant quantities of the core-forming material to the ethylene-vinyl acetate used to form the sheath avoids problems experienced heretofore in build-up of polymer in the forming dies using conventional filter-forming equipment. Additionally, the blended sheath-forming polymer improves adhesion between the sheath and the core of the bicomponent fiber and, with the use of polypropylene, improves the hardness of the resultant tobacco smoke filter elements.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: February 22, 2000
    Assignee: Filtrona International Limited
    Inventor: Richard M. Berger
  • Patent number: 5911224
    Abstract: A porous element particularly for use as a tobacco smoke filter plug in association with a cigarette or the like wherein the matrix comprises a multiplicity of biodegradable polyvinyl alcohol fibers bonded together at their points of contact to define a tortuous interstitial path for the passage of smoke. Because of the hygroscopic nature of polyvinyl alcohol, commercial production of such products require careful control of the moisture content of the polyvinyl alcohol fiber starting material, usually pre-drying the same to a residual moisture content of 7% by weight or less, and treatment of the low moisture fibrous mass by superheated steam to add about 2.5 to 5% moisture to a final moisture content of about 2.5 to 10%. The steam renders the fiber surface adhesive and, thus, bondable, and also lubricates the gathered fibers to improve processability.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: June 15, 1999
    Assignee: Filtrona International Limited
    Inventor: Richard M. Berger