Abstract:
The invention is directed to a corona charging device having a powder feed with an outlet. The device has an internal charging cavity having an inlet and a charged powder outlet. The powder feed outlet is positioned at the internal charging cavity inlet. The device is adapted to guide a powder stream downstream from the powder feed outlet to the charged powder outlet. The device also includes a corona charger having one or more projections positioned and adapted to facilitate a corona ion flow from the projections and intersecting the powder stream. The device also includes a rotating ground electrode adapted to be charged or grounded to attract the corona flow from the projections, and to rotate segments of the ground electrode between the internal charging cavity and a ground electrode cleaner.
Abstract:
Methods and systems for coating at least a portion of a medical device (e.g., a stent structure) include providing a plurality of coating particles (e.g., monodisperse coating particles) in a defined volume. For example, the particles may be provided using one or more nozzle structures, wherein each nozzle structure includes at least one opening terminating at a dispensing end. The plurality of coating particles may be provided in the defined volume by dispensing a plurality of microdroplets having an electrical charge associated therewith from the dispensing ends of the one or more nozzle structures through use of a nonuniform electrical field between the dispensing ends and the medical device. Electrical charge is concentrated on the particle as the microdroplet evaporates. With a plurality of coating particles provided in the defined volume, such particles can be moved towards at least one surface of the medical device to form a coating thereon (e.g., using an electric field and/or a thermophoretic effect).
Abstract:
A method and apparatus for providing a pattern on a solid dosage form, in which powder material is applied in a pattern to a substrate (3). A mask (5) having an aperture is provided between a source (1) of the powder material and the substrate (3) and the powder material is applied to the substrate through the mask (5). Relative movement of the substrate with respect to the source (1) of powder material is effected during the pattern application process.
Abstract:
An eye covering (700) for covering an exposed surface portion of an eye, the covering comprising a body having front and rear surfaces (702a and 701a) with the rear surface being shaped to conform to said exposed surface portion (701, 702) and at least a portion of the body comprising biologically compatible polymer fibre.
Abstract:
An eye covering (700) for covering an exposed surface portion of an eye, the covering comprising a body having front and rear surfaces (702a and 701a) with the rear surface being shaped to conform to said exposed surface portion (701, 702) and at least a portion of the body comprising biologically compatible polymer fibre.
Abstract:
The present invention provides an integrated structural unit that includes a diagnostic form that includes at least one active ingredient that is present in an amount that advantageously does not vary by more than about five percent from a predetermined target amount. In one embodiment, the unit form comprises a substrate, a deposit that is disposed on the substrate, and a spreading layer that overlies the deposit and is used to retain and spread a sample of liquid which is to be assayed. The deposit comprises a powder, including the active ingredient(s). The diagnostic form is created via a dry powder deposition apparatus that electrostatically deposits the powder on the substrate utilizing an electrostatic chuck and charged powder delivery apparatus.
Abstract:
A diffuser (518) comprises a conduit having a cross-sectional area that increases in a direction fluid flow. In one embodiment, the diffuser is used to reduce the incidence and severity of flow fluctuations that occur in an electrostatic deposition apparatus. In some embodiments, the diffuser includes one or more flow control features. A first flow-control feature comprises one or more appropriately-shaped annular slits (520) through which fluid having a greater momentum than a primary fluid moving through the diffuser is injected into the "boundary layer" near the wall of the diffuser. A second flow control feature comprises one or more annular slits (548) or, alternatively, slots or holes that are disposed at appropriate locations around the circumference of the diffuser through which a portion of fluid flowing in the boundary layer is removed. Boundary-layer flow removal is effected, in one embodiment, by creating a pressure differential across such annular slit or slots. Among other benefits, such flow control features reduce any tendencies for flow separation of the primary fluid in the diffuser.
Abstract:
A substrate (104) having a planar conductive plating (106) located on a first surface of a dielectric layer (108) and having a conductive collection trace (110) on a second surface of the dielectric layer (108) such that the conductive plating (106) and collection trace (110) have a parallel, spaced apart relation. The collection trace (110) is charged by supplying a voltage to the plating (106) and the trace (110) to establish a voltage differential across the dielectric layer (108). The material to be deposited (116) is charged to a polarity opposite that of the trace (110) so that the deposited material (102) is electrostatically retained.
Abstract:
A method of coating substrates of medicinal products with a dry powder includes the following steps: feeding the medicinal substrates onto a conveying belt (1); supplying the dry powder to a region (5) through which the substrates are to be conveyed; conveying the medicinal substrates on the conveying belt (1) through the region (5) with the conveying belt and/or the substrates maintained at a different electric potential from the dry powder, whereby the dry powder is attracted to the exposed surfaces of the substrates but is unable to reach the coated surfaces of the substrates in contact with the conveying belt, and treating the dry powder coatings to convert the powder into a fused film secured to the substrates.
Abstract:
Production of an electrosuspension of particles (5), comprising an insulating container (3) fitted with two spaced apart electrodes (2, 4) between which a high electrical potential is applied. At least one of the electrodes (2) is mounted for rotation by an associated electric motor (20). The electrode mounted for rotation preferably has a drum like configuration formed by a plurality of circumferentially spaced apart conductors (6). In a second aspect the invention produces an electrosuspension of micronised particles where one of the electrodes is in contact with a bed of particles and a second electrode is spaced above the particles. Field concentrating conductors are connected with the second electrode to generate ions and irradiate the surface of the particulate material with ions of opposite polarity to the first electrode.