Abstract: A photochromic contact lens having a period of time for discoloring the contact lens from a colored state to the uncolored state shortened, wherein the photochromic contact lens is made of an oxygen-permeable polymer material having a second-order transition point of not higher than 110° C., and formed to have an oxygen permeation coefficient of not less than 50, and wherein the contact lens contains a dye capable of exhibiting photochromism.

Abstract: It is an object of the present invention to provide an ophthalmic solution, which provides an enhanced comfort by suitably exhibiting an moisturizing effect to an eye and advantageously preventing an occurrence of unpleasant feelings caused by fluctuation of visual acuity. The ophthalmic solution of the present invention is provided by dissolving, in an aqueous medium, a hydroxypropylmethylcellulose, which has a molecular weight below a critical molecular weight for entanglements of an aqueous solution, which contains 3 w/w % of the hydroxypropylmethylcellulose, wherein kinematic viscosity of the ophthalmic solution at 20° C. is not higher than 2 mm2/s.

Abstract: It is an object of the present invention to provide an ophthalmic composition, wherein: the ophthalmic composition assures a sufficiently high degree of safety to eyes of the lens wearer; the ophthalmic composition reduces symptoms such as an unpleasant feeling or dryness of the eyes; the ophthalmic composition does not adversely affect a contact lens, such as a change of the size of the contact lens; and the ophthalmic composition advantageously improves a water wettability of surfaces of the contact lens, and the ophthalmic composition for the contact lens is prepared by adding at least one specific amino-sugar derivative to an aqueous medium.

Abstract: A photochromic contact lens having a period of time for discoloring the contact lens from a colored state to the uncolored state shortened, wherein the photochromic contact lens is made of an oxygen-permeable polymer material having a second-order transition point of not higher than 110° C., and formed to have an oxygen permeation coefficient of not less than 50, and wherein the contact lens contains a dye capable of exhibiting photochromism.

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: A process for preparing an ocular lens with a urethane compound comprising the steps of a) preparing a urethane compound by reacting at least one hydroxyl compound and at least one isocyanate compound in the presence of an organic iron compound, b) removing the organic iron compound from the urethane compound obtained in the step a) c) mixing the urethane compound obtained in the step b) with at least one compound selected from the group consisting of another copolymerizable compound, a crosslinking agent, a UV absorbent, a dye, a polymerization initiator, a photosensitizer, and an organic solvent to obtain a mixture, and d) curing the mixture obtained in the step c) to prepare a lens.

Abstract: A process for preparing an ocular lens with a urethane compound comprising the steps of

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: An ophthalmic composition which contains a component A consisting of at least one member selected from the group consisting of polyoxyalkylene block copolymers and their derivatives, and a component B consisting of at least one member selected from the group consisting of glycyrrhizic acid and its salts.

Abstract: An ophthalmic composition which contains a component A consisting of at least one member selected from the group consisting of polyoxyalkylene block copolymers and their derivatives, and a component B consisting of at least one member selected from the group consisting of glycyrrhizic acid and its salts.

Abstract: A process for preparing an urethane compound for medical instruments, characterized by reacting a hydroxyl compound (A) with an isocyanate compound (B) in the absence of a catalyst or in the presence of a reaction catalyst other than an organic tin compound to give an urethane compound (I). According to the process, the urethane compound showing high safety can be easily prepared, in particular, while molecular weight of the compound is controlled.

Abstract: A solution for contact lenses which comprises an amino acid type cationic surfactant and at least one nonionic surfactant.

Abstract: A solution for contact lenses which comprises an amino acid type cationic surfactant and at least one nonionic surfactant.

Abstract: A cleaning material for a contact lens formed of a polymer which is obtained by polymerizing a polymeric composition including at least a nonionic surface active agent having a polymerizable unsaturated double bond, and a cross-linking agent having a plurality of polymerizable unsaturated double bonds.

Abstract: An ocular lens obtained by reacting a hydroxyl group-containing polymer shaped to have an ocular lens shape, with a silicon-containing compound of the formula (I):O.dbd.C.dbd.N--R.sup.1 --Si.sub.n O.sub.n-1 (CH.sub.3).sub.2n+1 (I)wherein R.sup.1 is a C.sub.1-6 linear or branched alkylene group, and n is an integer of from 1 to 15.