Abstract: The present invention is related to water-based inks for making colored hydrogel contact lenses, in particular, colored HEMA-based hydrogel contact lenses. The ink of the invention comprises at least one colorant, water, and a water-soluble and actinically-curable binder polymer which is a vinyl group-terminated polyurethane polymer, a vinyl group-terminated polyurea binder polymer, or a mixture thereof. Also, the ink of the invention is characterized by having a viscosity greater than 50 centipoise (cps), a prolonged stability, and a good adhesion to a HEMA-based hydrogel contact lens. The ink of the invention preferably further has a good compatibility with a HEMA-based hydrogel material, and/or good transferability from a mold to a HEMA-based hydrogel contact lens made in the mold. The present invention is also related to a method for making colored hydrogel contact lenses using an ink of the invention.

Abstract: The present invention is related to water-based inks for making colored hydrogel contact lenses, in particular, colored HEMA-based hydrogel contact lenses. The ink of the invention comprises at least one colorant, water, and a water-soluble and actinically-curable binder polymer which is a vinyl group-terminated polyurethane polymer, a vinyl group-terminated polyurea binder polymer, or a mixture thereof. Also, the ink of the invention is characterized by having a viscosity greater than 50 centipoise (cps), a prolonged stability, and a good adhesion to a HEMA-based hydrogel contact lens. The ink of the invention preferably further has a good compatibility with a HEMA-based hydrogel material, and/or good transferability from a mold to a HEMA-based hydrogel contact lens made in the mold. The present invention is also related to a method for making colored hydrogel contact lenses using an ink of the invention.

Abstract: The present invention provides a radiation-curable prepolymer. The radiation-curable prepolymer of the invention is prepared by reacting an isocyanate-capped polyurethane with an ethylenically unsaturated amine or an ethylenically unsaturated monohydroxy compound or a mixture thereof, wherein the isocyanate-capped polyurethane is a copolymerization production of: (a) at least one polyalkylene glycol; (b) at least one branching agent having at least three hydroxy groups; and (c) at least one di- or polyisocyanate. The radiation-curable prepolymer of the invention can find use in economically producing contact lenses which have durable, highly elastic soft contact lenses with desired physical properties. In addition, the present invention provides method for making a radiation-curable prepolymer of the invention and for making a medical device, preferably an ophthalmic device, more preferably a contact lens.

Abstract: A prepolymer is prepared by reacting a mixture containing (a) at least one multifunctional compound, (b) at least one diisocyanate, and (c) at least one diol. The diol has a weight average molecular weight of at most 6000. The prepolymer, when reacted with an excess of water, forms a hydrogel polymer. The mixture of the prepolymer and water may be reaction molded, and used to form a contact lens.

Abstract: A prepolymer is prepared by reacting a mixture containing (a) at least one multifunctional compound, (b) at least one diisocyanate, and (c) at least one diol. The diol has a weight average molecular weight of at most 6000. The prepolymer, when reacted with an excess of water, forms a hydrogel polymer. The mixture of the prepolymer and water may be reaction molded, and used to form a contact lens.