Abstract: Disclosed are mold halves useful in molding a contact lens by polymerization of a polymerizable composition disposed between the mold halves. The mold halves are of rigid thermoplastic, preferably polystyrene, transparent to ultraviolet light.

Abstract: A device and method for high speed production rates in the hydration of soft contact lenses. Such device and method includes the use robotic transfer equipment to transfer contact lens molds containing contact lenses to and from a hydration station and a flushing station.

Abstract: A mixing device comprises a first cylinder (10) containing a particulate or powdered component (11) and having a closed first end (13, 14) and an opposite second end which is closed by a piston-like venting and filtering assembly (12, 15). The device also comprises a second cylinder (18) containing the liquid component (19) and having a closed end (20, 22) and an opposite open end sealingly receiving the closed end of the first cylinder (10) therein in a piston-like manner. Means (14) are provided for communicating between the inner space of the first and second cylinders (10, 18) through the closed end (13, 14) of the first cylinder (10), when the first cylinder is forced into the second cylinder, whereby liquid from the first cylinder is injected into interstices defined between the particulate component contained in the first cylinder for providing a paste-like material. The communicating means is preferably formed by a breakable membrane (14).

Abstract: Male and female members for contact lenses where either member is able to hold the contact lens as it moves from station to station during the hydration process. The female member fits together with the male member forming a chamber. Each of the members contains a line centrally located so that both surfaces of the contact lens are flushed during the hydration process, and drainage takes place radially on the outside of the mated male and female chamber members. These members may be produced on a frame with a plurality of members, usually eight to a frame, to allow ease of processing. Full automation is possible, and complete and positive lens control during any step of the process through the packaging step is achieved.

Abstract: A process for releasing leachable substances from a polymeric contact lens blank. the contact lens is confined in a cavity within a carrier to permit the hydration of the lens without permitting it to invert or roll over. A fluid flow is introduced into the cavity about the lens to extract leachable material from the lens. The process significantly reduces the amount of leaching fluid that is used and the amount of time that is needed for hydration, washing and extraction.

Abstract: Shaped hydrogel articles such as soft contact lenses are prepared by (1) molding or casting a polymerization mixture comprising: (a) a monomer mixture comprising a major proportion of a hydrophilic (meth)acrylate ester such as 2-hydroxyethyl methacrylate, an alkyl (meth)acrylate wherein the alkyl group contains at least four carbon atoms, and a cross-linking monomer; and (b) a water-displaceable diluent, wherein said diluent has a viscosity of at least 100 MPa Sec at 30.degree. C., and wherein said diluent consists essentially of a boric acid ester of certain dihydric alcohols, said dihydric alcohols having Hansen polar (w.sub.p) and Hansen hydrogen bonding (w.sub.h) cohesion parameters falling within the area of a circle defined as having a center at w.sub.h =20.5, w.sub.p =13, and a radius of 8.5, to produce a shaped gel of a copolymer of said monomers and said diluent, and (2) thereafter replacing said diluent with water.

Abstract: An acrylate based bone cement with well balanced low exotherm, low residual monomer, and high strength properties formulated from (1) a liquid component containing at least three different monomeric (meth)acrylates, e.g. a C.sub.1 -C.sub.2 alkyl methacrylate, a straight or branched long chain (meth)acrylate having a molecular weight of at least 168, and a cyclic (meth)acrylate having a molecular weight of at least 168, and (2) a polymer powder component containing (meth)acrylate polymers or copolymers. The final bone cement may also contain conventional additives such as polymerization inhibitors, activators, crosslinkers, X-ray contrast material, polymerization initiators, antibiotics, antiseptics, and the like.

Abstract: Shaped hydrogel articles such as soft contact lenses are prepared by (1) molding or casting a polymerization mixture comprising: (a) a monomer mixture comprising a major proportion of a hydrophilic (meth)acrylate ester such as 2-hydroxyethyl methacrylate, and a cross-linking monomer; and (b) a water-displaceable diluent, wherein said diluent has a viscosity of at least 100 MPa Sec at 30.degree. C., and wherein said diluent consists essentially of a boric acid ester of certain dihydric alcohols, said dihydric alcohols having Hansen polar (.delta..sub.p) and Hansen hydrogen bonding (.delta..sub.h) cohesion parameters falling within the area of a circle defined as having a center at .delta..sub.h =20.5, .delta..sub.p =13, and a radius of 8.5, to produce a shaped gel of a coploymer of said monomers and said diluent, and (2) thereafter replacing said diluent with water.

Abstract: A method for forming shaped hydrogel articles such as soft contact lenses wherein hydrophilic monomers are mixed with an inert diluent prior to polymerization, and the diluent is replaced with water following the polymerization. Diluents yielding optically clear hydrogels with good mechanical properties are selected on the basis of their viscosity and their Hanson cohesion parameters relative to the cohesion parameters of the polymeric component of the hydrogel.