Patents Assigned to E. I. Du Pont de Nemours and Co.
  • Immunoassay wherein labeled antibody is displaced from immobilized analyte-analogue
    Patent number: 4434236
    Abstract: A method for the rapid determination of analyte in a sample is provided. The sample is contacted with a solid phase having immobilized thereon an analyte-analogue to which there is displaceably bound a labeled anti-analyte antibody. Because the antibody has greater affinity for the analyte than the analyte-analogue, the labeled antibody is displaced from the solid phase. The complex is separated from the solid phase, and the amount of complex is measured. The measured amount is related to the amount of analyte initially present in the sample.
    Type: Grant
    Filed: October 20, 1982
    Date of Patent: February 28, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: J. William Freytag
  • Ultrasonic vibrator for applying finish to yarn
    Patent number: 4431684
    Abstract: An ultrasonic vibrator of the type used to atomize liquid is used for applying liquid finish to a moving threadline. The liquid is supplied to a through passage in the tip of the horn of the vibrator in which it is atomized and applied to the threadline which is moving through the passage in the tip of the horn.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: February 14, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Alfred J. Strohmaier
  • Cell washing apparatus having radially inwardly directed retaining arms
    Patent number: 4431423
    Abstract: A cell washing apparatus having a pivotally movable sample tube holder provided with a radially inwardly directed arm having a grasping hook thereon. The hook engages a retaining surface disposed radially inwardly of the pivot point of the holder to restrain radial outward movement of the sample tube holder.
    Type: Grant
    Filed: March 10, 1982
    Date of Patent: February 14, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Oakley L. Weyant, Jr.
  • Ice-filled structure and tunnelling method for the egress and launching of deep-based missiles
    Patent number: 4431349
    Abstract: Missiles located in the deeper (hard rock) portion of a shaft or tunnel are protected from damage during a nuclear attack by a mass of ice, preferably trumpet-shaped, located in the outermost portion (e.g., 600-900 meters). When missile egress is required, an ice-supported passageway is bored through the ice, preferably by melting. The trumpet shape assures a straight path for missile egress even if the shaft or tunnel should become transversely displaced by a cratering explosion against the surface.
    Type: Grant
    Filed: April 14, 1982
    Date of Patent: February 14, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: David L. Coursen
  • Delay detonator
    Patent number: 4429632
    Abstract: Improved uniformity of timing, and particularly reduced sensitivity of timing to minor variations in delay charge size, are achieved in delay detonators by placing a loose load of a flame-sensitive ignition composition between a pressed delay charge and an ignition assembly, e.g., a percussion primer, at the actuation end of the detonator. The loose ignition charge has a free surface and is adapted to be ignited in response to direct contact with flame emitted from the ignition of a charge in the ignition assembly. Preferably, the delay charge is pressed into a plastic carrier which, in a non-electric detonator, has an open end terminating between the walls of the detonator shell and a primer shell that closes the actuation end of the detonator, and the ignition charge is loosely loaded into a metal capsule seated against the delay charge.
    Type: Grant
    Filed: April 27, 1981
    Date of Patent: February 7, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Malak E. Yunan
  • Control valve
    Patent number: 4429714
    Abstract: A flow control valve having a flow-dividing cage surrounding its plug. The cage includes stacked plates spaced by dependent legs and annular screens in the spaces between adjacent plates.
    Type: Grant
    Filed: August 3, 1981
    Date of Patent: February 7, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: Allan B. Hughes, Terrence A. Dear
  • Injector mixer apparatus
    Patent number: 4430001
    Abstract: An apparatus and process for uniformly mixing a relatively small amount of material with a relatively large amount of another material in particulate form by introducing the smaller amount of material via a pipe within another concentric pipe through which a high pressure gas is introduced which thereby provides a zone of turbulence into which a particulate material in larger amounts is introduced, the mixture of gas and materials being transported through a treatment chamber to produce a uniform mixture.
    Type: Grant
    Filed: September 28, 1981
    Date of Patent: February 7, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: George A. Schurr
  • Cyclic monomers derived from trifluoropyruvate esters
    Patent number: 4429143
    Abstract: Perhalogenated dioxoles, halogenated dioxolanes, a process for making the dioxoles and dioxolanes, and polymers of dioxole and dioxolane monomers.
    Type: Grant
    Filed: September 28, 1981
    Date of Patent: January 31, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: Burton C. Anderson, David C. England, Paul R. Resnick
  • Photoimaging process
    Patent number: 4429027
    Abstract: A simplified method for photoimaging a photosensitive layer produces in situ a radiation-opaque photomask on the photosensitive layer or on a cover sheet of the layer. A nonvisible latent image is toned and the toner is transferred to a layer or cover sheet to form an actinic radiation-opaque photomask.
    Type: Grant
    Filed: May 21, 1981
    Date of Patent: January 31, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: Vaughan C. Chambers, Jr., Joseph E. Gervay
  • Single exposure positive-working photopolymer element
    Patent number: 4427758
    Abstract: A high speed, positive-working photopolymer element comprising, in order: (1) a support, (2) a nonphotosensitive layer comprising a hardenable binder (e.g., gelatin) containing a releasable hardener (e.g., glutaraldehyde-bisulfite), and an optional colorant, and (3) a permeable photopolymerizable layer. Imagewise exposure of the photopolymerizable layer is followed by diffusion of an alkali through the nonimage area, releasing the hardener. A subsequent wash-off step produces a positive image of the original.
    Type: Grant
    Filed: October 1, 1981
    Date of Patent: January 24, 1984
    Assignee: E. I. Du Pont de Nemours and Co.
    Inventor: John A. Quinn
  • High speed etching of polyimide film
    Patent number: 4426253
    Abstract: An aqueous solution of ethyl or propyl alcohol containing a basic compound such as KOH is shown to etch the surface of polyimide material up to 400 times faster than conventional aqueous KOH etching solutions.
    Type: Grant
    Filed: December 3, 1981
    Date of Patent: January 17, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: John A. Kreuz, Christopher M. Hawkins
  • End capping an optical fiber
    Patent number: 4425375
    Abstract: Contacting a rough cut optical fiber end to a light-transmissible, hardenable material supported on a smooth substrate and thereafter hardening the material to form a smooth flat light transmissible surface at the end of the fiber.
    Type: Grant
    Filed: April 25, 1983
    Date of Patent: January 10, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Edward A. Abramson
  • Flexible screen-printable conductive composition
    Patent number: 4425263
    Abstract: A screen-printable thick film conductor composition for membrane switches consisting of an active phase of conductive metal powder dispersed in an organic medium consisting essentially of a linear aromatic polyester resin dissolved in volatile solvent.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: January 10, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Nicholas Nazarenko
  • Polytetrafluoroethylene resin with degradation retarder
    Patent number: 4425448
    Abstract: Zeolites, including ultramarine blue, retard the oxidative degradation of polytetrafluoroethylene resin (PTFE) at elevated temperatures. Coating compositions of PTFE, zeolites, acrylic resin and iron-containing pigments are provided.
    Type: Grant
    Filed: May 20, 1982
    Date of Patent: January 10, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: Thomas P. Concannon, Mitzie K. Rummel
  • Hydrogen peroxide in sulfuric acid extraction of uranium ores
    Patent number: 4425307
    Abstract: Uranium can be extracted from its ores at a pH of 2.5 to 5.5 using sulfuric acid, hydrogen peroxide, trace of iron and a sulfate. The extraction process is applicable to both tank leaching of conventionally mined ores and in situ leaching.
    Type: Grant
    Filed: April 22, 1981
    Date of Patent: January 10, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Frederick W. DeVries
  • Herbicidal sulfonamides
    Patent number: 4425153
    Abstract: This invention relates to ortho(acyloxy)benzenesulfonamides and their use as herbicides.
    Type: Grant
    Filed: January 18, 1982
    Date of Patent: January 10, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: John B. Adams, Jr.
  • Laminated sheet structures
    Patent number: 4424253
    Abstract: Blends of chlorinated hydrocarbon rubber selected from chlorosulfonated polyethylene having about 22-28 weight % Cl and 0.4-1.2 weight % S and chlorinated polyethylene having about 22-28 weight % Cl with EPM or EPDM elastomers in a proportion of 75-93% of the former and 7-25% of the latter can be compounded with usual fillers, pigments, stabilizers, and processing aids and formed into sheets which form hot bonded laminate structures with linear ethylene polymer sheets. Such laminate structures have very good adhesion peel strength, good mechanical strength and stretchability and are particularly useful in making pool and pond liners.
    Type: Grant
    Filed: February 25, 1982
    Date of Patent: January 3, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Bernard F. Anderson
  • Centrifuge rotor apparatus for preparing particle spreads
    Patent number: 4423699
    Abstract: A centrifuge rotor is described which facilitates the preparation of cell dispersions on microscope slides. The rotor is bowl-like in configuration and defines an annular channel having plural circumferentially disposed septa. The septa provide plural separate regions each adapted to receive removable chambers. The outer wall in each region is flat to accommodate a microscope slide. Each chamber has an outlet orifice adapted to contact the microscope slide. A sample containing blood cells, for example, may be placed in each chamber and the cells centrifugally sedimented against the slide associated with the respective chambers. A gasket at the interface between each slide and its chamber prevents leakage of the sample and a conduit in each chamber permits removal of the supernatant fluid following cell sedimentation.
    Type: Grant
    Filed: February 28, 1979
    Date of Patent: January 3, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventors: John W. Boeckel, Vernon C. Rohde, John R. Wells
  • Benezenesulfonylisocyanates
    Patent number: 4424377
    Abstract: This invention relates to a novel class of N-(heterocyclicaminocarbonyl)-o-alkoxymethylbenzene sulfonamide herbicides.
    Type: Grant
    Filed: May 14, 1982
    Date of Patent: January 3, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Gregory W. Schwing
  • Blends of low molecular weight hydroxy-terminated polyesters and coatings based on these blends
    Patent number: 4424296
    Abstract: Blends of low molecular weight hydroxy-terminated polyesters, based on diols, such as 2,2,4-trimethyl-1,3-pentane diol, and diacids or their esters, such as isophthalic acid, and methyl esters of short chain aliphatic diacids, are provided. The blends can be crosslinked with conventional crosslinking agents such as nitrogen resins or polyisocyanates. The formulated coatings have high solids content of relatively low viscosities and are useful on e.g. metallic substrates forming, upon curing, coatings having excellent tensile strength, hardness, and resistance to staining, weathering, and corrosive conditions.
    Type: Grant
    Filed: September 29, 1978
    Date of Patent: January 3, 1984
    Assignee: E. I. Du Pont de Nemours & Co.
    Inventor: Joseph A. Antonelli