Patents Assigned to Hercules
  • Patent number: 5541241
    Abstract: At least 20% of poly(vinyl alcohol) (PVA) is dispersed in an aqueous solution of at least one salt dissolved therein selected from the group of sodium or potassium formate, sodium, potassium, or magnesium sulfate, sodium or potassium citrate, sodium or potassium polyacrylate, or mixtures thereof. This aqueous suspension of PVA is useful in systems in which PVA is dissolved in order to reduce the time of dissolution.
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: July 30, 1996
    Assignee: Hercules Incorporated
    Inventors: Charles L. Burdick, James L. Latta
  • Patent number: 5541304
    Abstract: This invention provides a method of altering the water content of a hydrogel comprising treatment of said hydrogel with a liquid dehydrating composition. There is further provided a method of altering the water content of a hydrogel-containing medical device. The medical devices of the present invention comprise a hydrogel having a water level ex vivo lower than the thermodynamic equilibrium water level when in vivo. These medical devices comprise a hydrogel contacted with a liquid dehydrating agent, wherein said medical device has a lower water level ex vivo than the thermodynamic equilibrium water level when the medical device is in vivo.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: July 30, 1996
    Assignee: Hercules Incorporated
    Inventor: Samuel A. Thompson
  • Patent number: 5540953
    Abstract: A fiber comprising a polyolefin fiber having a finish which comprises an antistatic composition, wherein the fiber with the finish has a hydrostatic head value at least about 102 mm and is capable of being processed into a nonwoven fabric on processing equipment comprising at least one card and means for bonding the fabric at a throughput of at least about 128 pounds/hours for a period of at least two hours without formation of significant solid antistatic composition build-up on the nonwoven fabric processing equipment, and related compositions and processes, and articles made with such fibers.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: July 30, 1996
    Assignee: Hercules Incorporated
    Inventor: James H. Harrington
  • Patent number: 5534340
    Abstract: The fabrics of this invention have a unique combination of liquid barrier properties and high air permeability and comprise at least one carded nonwoven web comprising at least 10% by weight, based on the total weight of cardable fibers, of cardable polyolefin fibers having a fiber fineness of about 0.5 to about 1.2 decitex. Preferably the polyolefin fibers are hydrophobic polyolefin fibers, and the nonwoven material is thermally bonded. Laminates comprising at least one layer of the fabrics of this invention and at least one layer of another nonwoven material have the same unique combination of properties.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: July 9, 1996
    Assignee: Hercules Incorporated
    Inventors: Rakesh K. Gupta, Richard J. Legare
  • Patent number: 5531735
    Abstract: The invention discloses temporary medical devices such as stent implants which can be disintegrated in-vivo upon demand by release of an agent held trapped within the device. The device is fabricated from a matrix polymer material which is essentially insoluble in body fluids and a disintegration agent which acts to initiate decomposition of the matrix polymer when contacted therewith. The disintegration agent is trapped within and chemically isolated from the matrix polymer such as by encapsulation, and is releasable within the matrix polymer upon contact of the device with a releasing agent which liberates the encapsulated disintegration agent.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: July 2, 1996
    Assignee: Hercules Incorporated
    Inventor: Samuel A. Thompson
  • Patent number: 5531716
    Abstract: The present invention provides medical devices comprised of ionically crosslinked polymer, especially, stents, catheter or cannula components, plugs, and constrictors. The medical devices of the present invention are prepared by treatment of ionically crosslinkable polymer compositions with crosslinking ion compositions to provide ionically crosslinked materials.An important aspect of the present invention is that these medical devices can be disintegrated in-vivo at a desired time through the exposure of the medical device to a chemical trigger which generally is described as an agent that acts to displace the crosslinking ion in the ionically crosslinked material through binding or simple replacement with a non-crosslinking ion.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: July 2, 1996
    Assignee: Hercules Incorporated
    Inventors: Gary A. Luzio, Samuel A. Thompson
  • Patent number: 5531727
    Abstract: A nonwoven fabric having flow control properties suitable for use in a fluid absorbing article such as a diaper, incontinence pad, or the like; and a process for preparation thereof by utilizing unbonded carded staple fiber elements or webs having different average dpf values compiled in graduated order from high-to-low average dpf, then compressed and bonded to a desired constant fabric density.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: July 2, 1996
    Assignee: Hercules Incorporated
    Inventors: Richmond R. Cohen, Edward J. Engle
  • Patent number: 5525664
    Abstract: A process for making wet strengthened paper comprises (1) treating an aqueous suspension of papermaking fibers with a composition comprising (a) a cationic polymer that cures at a neutral pH and is capable by itself of conferring wet strength to paper, the resin having a multiplicity of 3-hydroxyazetidinium ion groups along the polymer chain, and (b) a water-soluble carboxyalkylated polyamine polymer or a carboxylic acid salt thereof.
    Type: Grant
    Filed: December 2, 1994
    Date of Patent: June 11, 1996
    Assignee: Hercules Incorporated
    Inventors: Andrew J. Miller, Brian M. Stubbs
  • Patent number: 5525180
    Abstract: Chopped fiber strands are produced by (1) wetting a continuous unsized fiber tow with a volatile sizing agent, (2) chopping the wet fiber tow into predetermined lengths, and (3) exposing the chopped fibers to conditions of temperature and pressure that remove the sizing agent by volatilizing but do not cause any structural changes in the fiber. Bundles of the unsized fibers have a high bulk density and are easily dispersible in air or other media to individual filaments or groups of small numbers of individual filaments. The process is especially useful for producing high bulk density packages of polyacrylonitrile-based carbon fibers.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: June 11, 1996
    Assignee: Hercules Incorporated
    Inventors: James T. Paul, Jr., Warren C. Schimpf
  • Patent number: 5525738
    Abstract: A process is disclosed for the synthesis of alkyl ketene dimers by the dehydrohalogenation of a C.sub.8 -C.sub.22 saturated or unsaturated linear fatty acid halide, comprising reacting the fatty acid chloride with a cyclic tertiary amine in a solvent that is selected from the group consisting of cycloalkanes and alkanes at a temperature of up to 75.degree., mechanically separating tertiary amine hydrochloride salts from alkyl ketene dimer dissolved in the solvent, and recovering the alkyl ketene dimer from the solvent.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: June 11, 1996
    Assignee: Hercules Incorporated
    Inventor: Jian J. Zhang
  • Patent number: 5523374
    Abstract: Curable compositions including epoxy-functional compounds and polyenes, as well as cyclic polysiloxanes, and/or tetrahedral siloxysilanes, and/or linear polysiloxanes; along with, or instead of these polyenes and silicon compositions, crosslinkable prepolymers prepared from such polyenes and silicon compounds may be included. A curing agent, and yet additionally, a curing accelerator, may also be included. These compositions can be thermally cured, in the presence of hydrosilation catalysts.
    Type: Grant
    Filed: October 26, 1993
    Date of Patent: June 4, 1996
    Assignee: Hercules Incorporated
    Inventors: John K. Bard, Richard L. Brady, Raymond T. Leibfried, De K. Loo
  • Patent number: 5522904
    Abstract: A femoral implant for a hip prosthesis includes a shaft oriented in a longitudinal direction and a neck extending from said shaft at an acute angle .theta. to the longitudinal direction. The implant includes a plurality of layers of fibers in a matrix, wherein the fibers are substantially unidirectional in each respective layer. The implant is made from a stack of layers of the matrix so that the direction of fibers is unbalanced. At least 50% of the fibers are oriented in the .theta. direction and the remainder of said fibers are oriented in directions other than the .theta. angle.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: June 4, 1996
    Assignee: Hercules Incorporated
    Inventors: James M. Moran, Richard A. Salzstein, Isaac M. Daniel, Douglas S. Cairns, Daniel B. Smith
  • Patent number: 5522794
    Abstract: Method of enhancing the healing of human wounds by controlling the microenvironment of the wound by sequentially applying to the wound dressings having moisture and oxygen permeabilities appropriate for the healing phases of the wound.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: June 4, 1996
    Assignee: Hercules Incorporated
    Inventor: Ralph Ewall
  • Patent number: 5520756
    Abstract: Stable plasticizer system and corresponding nitrocellulose/nitroguanidine nitramine-type LOVA propellant compositions utilizing such system.
    Type: Grant
    Filed: October 16, 1992
    Date of Patent: May 28, 1996
    Assignee: Hercules Incorporated
    Inventor: Edward H. Zeigler
  • Patent number: 5516971
    Abstract: An improved non-pyrolytic disposal process for nitrocellulose-based explosives and rocket propellants is disclosed. Explosive and propellant particles are digested by contact of the particles with an aqueous solution containing from about 5 to 20% by weight caustic (NaOH) maintained at a temperature of about 50.degree. C. to 100.degree. C. and under conditions of agitation until digestion is essentially complete. The resulting by product contains a mixture of depleted caustic and a water soluble sludge which can be disposed of or further processed. The process minimizes environmental concerns brought about by the open burning of high energy materials.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: May 14, 1996
    Assignee: Hercules Incorporated
    Inventor: Eldon K. Hurley
  • Patent number: 5512376
    Abstract: A reactive component, which is curable to form a nonpolar polymer containing silicon and carbon atoms, and having a glass transition temperature of at least 20.degree. C., is mixed with an antiplasticizer. The resulting mixture, a curable composition, is cured to form a composition having an increased modulus. The reactive component preferably comprises a polyene having at least two hydrosilation reactive carbon-carbon double bonds (e.g., dicyclopentadiene), and a silicon compound having at least two hydrosilation reactive .ident.SiH groups. Preferably the silicon compound comprising at least one member selected from the group consisting of cyclic polysiloxanes, tetrahedral siloxysilanes, and linear polysiloxanes. Preferably the resulting cured composition is crosslinked, due to at least one member selected from the group consisting of the polyene and the silicon compound having more than two hydrosilation reactive sites. Preferably the curable composition further comprises a hydrosilation catalyst.
    Type: Grant
    Filed: June 20, 1994
    Date of Patent: April 30, 1996
    Assignee: Hercules Incorporated
    Inventors: Richard L. Brady, Samuel A. Thompson
  • Patent number: 5512622
    Abstract: A resinous binder formulation is disclosed which relates to binders containing dilution-enhancing polymers for "letdown" metal resinate vehicles in publication gravure printing inks. The resinous binder comprises a metal resinate, and a dilution-enhancing polymer selected from the group consisting of polymers of maleic anhydride and ethylene and polymers of acrylonitrile, butadiene, acrylic acid and/or methacrylic acid. The dilution-enhancing polymer being present in the resinous binder in an amount which is effective to increase the dilution of the resinous binder in aromatic and nonaromatic solvents.Also disclosed is a publication gravure ink comprising a mixture of a solvent, a colorant and the resinous binder.
    Type: Grant
    Filed: November 17, 1994
    Date of Patent: April 30, 1996
    Assignee: Hercules Incorporated
    Inventors: Frank P. Tise, Jennifer Weatherdon
  • Patent number: 5510004
    Abstract: The use of polymers and copolymers of N,N-diallyl-3-hydroxyazetidinium salts as agents for improving the wet strength of paper wherein the polymers have a reduced level of organohalide by-products. Also encompassed are paper furnishes and paper containing the polymers and copolymers.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: April 23, 1996
    Assignee: Hercules Incorporated
    Inventor: Anthony J. Allen
  • Patent number: 5502140
    Abstract: A hydrocarbon resin is prepared by (1) thermally polymerizing a mixture consisting essentially of (a) about 40% to 90% by weight based on total monomers of a cyclic diolefin component comprising at least about 50% by weight dicyclopentadiene, and (b) about 60% to 10% by weight based on total monomers of a specified vinyl aromatic component, preferably alpha-methylstyrene; para-methyl-.alpha.-methylstyrene; 2,4-diphenyl-4-methyl-1-pentene, or mixtures thereof, and (2) recovering a product having a Ring and Ball softening point of about 70.degree. to about 150.degree. C. Hydrogenation of this resin produces light colored, thermally stable products that are useful as tackifiers in adhesives.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: March 26, 1996
    Assignee: Hercules Incorporated
    Inventors: Norman E. Daughenbaugh, Dane G. Goodfellow, Deborah A. Riedl
  • Patent number: 5502091
    Abstract: A process for making paper to enhance the dry strength of the paper produced without substantially reducing its softness comprising adding to a bleached pulp furnish, separately or together, (1) an anionic polymer selected from the group consisting of carboxymethyl guar, carboxymethyl bean gum, carboxymethyl hydroxyethyl guar, and a carboxymethyl hydroxypropyl guar, with (2) a cationic polymer selected from the group consisting of a cationic guar, a cationic acrylamide copolymer, a cationic bean gum, a cationic amine-epichlorohydrin wet strength resin, and both a cationic wet strength resin and at least one of the other said cationic polymers, a composition for adding to a paper-making pulp slurry comprising the said polymers, a method for making the said composition, and a paper product containing the said composition, are disclosed.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: March 26, 1996
    Assignee: Hercules Incorporated
    Inventor: Sunil P. Dasgupta