Abstract: The present invention provides apparatus and methods for injection molding polymeric cannulae from liquid polymeric materials. The method includes injecting pressurized liquid polymer into a mold cavity and into an overflow and forming a conduit by forcing pressurized working fluid through the solidifying liquid polymer into the overflow. The invention provides a mold for fluid-assisted injection molding articles from polymeric materials, the mold comprising at least two parts defining a cavity having a conduit portion incorporating a needle portion; a channel for liquid polymer ingress; a channel for pressurized fluid ingress; and an overflow in communication with the conduit portion. The mold may incorporate a plurality of cavities. Preferably the volume of the overflow is equal to or greater than the volume of the conduit portion. Preferably the mold incorporates a separating means for separating the overflow from a cannula portion of an article formed in the mold.

Abstract: The present invention provides a cannula comprising of a core needle and a sleeve, the core needle and sleeve spaced by conduit-forming projections. The projections may be aligned axially along the surface of the core needle or the inner surface of the sleeve. Engagement of the core needle with a sleeve forms a composite needle having one or multiple conduits for fluid transfer the length of the cannula. Engagement of the core needle and sleeve may be enhanced with different engagement means. Preferably the core needle and sleeve comprise of polymeric materials. The invention most advantageously can be produced without the need for a core pin in the formation of the core needle or sleeve. A composite needle may incorporate a sharp tip for penetration of materials and a side port for transfer of fluids. Alternatively, the composite needle may be blunt at the tip.

Abstract: The invention provides methods and apparatus for reconstituting fluids and substances and injecting the reconstituted materials. Apparatus may include an injection needle having a hub, a draw-up needle having a hub, and a safety cap for engagement with a syringe barrel or reservoir for transfer and/or reconstitution and injection of fluids. The apparatus includes engagement means for securely engaging the hubs of the needles and/or cap to minimise inadvertent pricks with either of the needles during the filling of a syringe with reconstituted materials and injecting the materials. Preferably the engagement means incorporates a channel on one hub and a protrusion on the other hub. The system may incorporate a second bore for quick draw-up of materials and fluids for injection. Preferably, the apparatus comprises of polymeric materials which can be injection moulded. The invention includes methods for drawing-up and reconstituting fluids for injection.

Abstract: The present invention provides apparatus and methods for injection moulding polymeric articles. The method includes injecting pressurised liquid polymer into a mould cavity, the cavity incorporating a core pin and a pressure distribution means. Preferably the article is a cannula. The invention provides a mould for injection moulding articles from polymeric materials, the mould comprising at least two parts defining a cavity having a conduit portion incorporating a needle portion; a channel for liquid polymer ingress; a channel for pressurised fluid ingress; a core pin for defining the conduit of a cannula, and a pressure distribution means for controlling the distribution of the pressurised liquid polymer. The end surface of the pressure distribution means defines the tip geometry of the cannula. The mould may incorporate a plurality of cavities. The method includes moving the pressure distribution means in a controlled manner to define the conduit of the cannula.

Abstract: The present invention provides apparatus and methods for injection moulding polymeric cannulae from liquid polymeric materials. The method includes injecting pressurised liquid polymer into a mould cavity and into an overflow and forming a conduit by forcing pressurised working fluid through the solidifying liquid polymer into the overflow. The invention provides a mould for fluid-assisted injection moulding articles from polymeric materials, the mould comprising at least two parts defining a cavity having a conduit portion incorporating a needle portion; a channel for liquid polymer ingress; a channel for pressurised fluid ingress; and an overflow in communication with the conduit portion. The mould may incorporate a plurality of cavities. Preferably the volume of the overflow is equal to or greater than the volume of the conduit portion. Preferably the mould incorporates a separating means for separating the overflow from a cannula portion of an article formed in the mould.