Abstract: The present invention provides a poly(ethylene) glycol based polyurethane polymer composition, particularly useful in the production of contact lenses. Generally the reactant mixture used to form the polymer includes a branched chain extender. There is also provided a method of manufacturing a contact lens formed from such a polymer.

Abstract: According to the present invention, there is provided a contact lens assembly comprising a contact lens having an outer edge, a flash ring disposed around the outer edge of the contact lens and a connecting portion connecting the flash ring to the contact lens, wherein the thickness of the connecting portion is less than the thickness of the outer edge of the contact lens. There is also provided a contact lens assembly comprising a contact lens having an outer edge, a flash ring disposed around the outer edge of the contact lens, and a connecting portion connecting the flash ring to the contact lens wherein the mass of the flash ring is at least forty times greater than the mass of the contact lens, suitably at least sixty times greater than the mass of the contact lens.

Abstract: The present invention relates to a polyurethane polymer composition prepared by reacting a mixture comprising: a} at least one polyethylene glycol, and either b) at least one poly-isocyanate, having a functionality greater than 2 or c) at least one di-isocyanate and at least one polyol or at least one macropolyol having a functionality greater than 2, wherein the polyol or macropolyol is present at an amount of 0.1 to 9 wt % of the mixture. The invention also relates to a process for preparing a polyurethane xerogel in the form of a molded article, said process comprising the steps of: i.) preparing said mixture; ii.) dispensing the reaction mixture formed in step i) into a mold; iii.) allowing the reaction mixture to react and cure; iv.) removing the molded article from the mold; and v.) hydrating the molded article.

Abstract: The present invention relates to a polyurethane polymer prepared from a mixture comprising: (a) at least one polyol of formula (I), wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated polyoxyalkylene group, and the remainder of X1, X2, X3. X4 and X5 are each independently H or absent, and Z is a central linking unit; (b) at least one di- or poly-isocyanate; and (c) optionally at least one OH-terminated chain extender. Further aspects of the invention relate to a process for preparing a polyurethane, and to a process for preparing a contact lens.

Abstract: There is provided a polyurethane xerogel prepared from a mixture comprising: (a) at least one isocyanate, (b) at least one silicone containing compound of formula J: wherein at least one group represents a hydrocarbyl group and p represents an integer of from 1 to 40, or at least one R2 group represents a hydrocarbyl group and q represents an integer of from 1 to 40; and at least one R3 group represents a hydrocarbyl group and w represents an integer of from 1 to 40, or at least one R4 group represents a hydrocarbyl group and y represents an integer of from 1 to 40; (c) optionally one or more additional components; wherein the isocyanate and silicone containing compound are reacted under substantially anhydrous conditions. There is also provided a contact lens formed from the polyurethane xerogel.

Abstract: The present invention relates to a thermoplastic polyurethane contact lens prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; and (c) at least one diol of formula (I): wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a contact lens.

Abstract: The present invention relates to polyurethane polymer compositions prepared by reacting a mixture comprising: a) at least one poly(ethylene glycol), b) at least one polyoxyalkylene diol (typically PPG or a copolymer of ethylene oxide and propylene oxide), c) at least one di- or poly-isocyanate, d) at least one polyol or macropolyol having a functionality greater than 2, or a mixture of such polyols or macropolyols having a functionality greater than 2, e) optionally an additional compound comprising at least one hydroxyl group and at least one primary or secondary amine group. The present invention also relates to an article comprising such a polymer, in particular a medical device such as a contact lens. A process for preparing a polyurethane hydrogel is also provided.

Abstract: The present invention relates generally to production of thermoplastic materials which swell in water to produce hydrogels. These materials will hereafter be referred to as “thermoplastic hydrogels”. They are useful as contact lenses or for use in vision correction prosthetics or as cosmetic devices. In particular, the invention relates to thermoplastic hydrogels which show improved flow characteristics.

Abstract: The present invention relates generally to production of thermoplastic materials which swell in water to produce hydrogels. These materials will hereafter be referred to as “thermoplastic hydrogels”. They are useful as contact lenses or for use in vision correction prosthetics or as cosmetic devices. In particular, the invention relates to thermoplastic hydrogels which show improved flow characteristics.

Abstract: A linear random block copolymer comprising segments of polyethylene oxide and a relatively more hydrophobic polymer, e.g. polypropylene oxide connected by hydrophobic segments containing urethane and urea groups formed from the reaction of a di-isocyanate and a diamine, wherein the diamine comprises less than 2% by weight of the total weight of the reactants used in the preparation of the copolymer.

Abstract: The present invention relates generally to production of thermoplastic materials which swell in water to produce hydrogels. These materials will hereafter be referred to as “thermoplastic hydrogels”. They are useful as contact lenses or for use in vision correction prosthetics or as cosmetic devices. In particular, the invention relates to thermoplastic hydrogels which show improved flow characteristics.