(JP9511000-W)      The following are claimed: (a) a method of producing an optically clear contact lens by treating the lens with a supercritical fluid; (b) a method of dry releasing a contact lens from a mould in which the lens was moulded by treating the contact lens and mould with a supercritical fluid; and (c) a method of extracting incompletely polymerised materials from a contact lens by treating the lens with a supercritical fluid. Pref. the supercritical fluid is supercritical carbon dioxide, nitrous oxide, ethane or propane; supercritical carbon dioxide is most pref.. An additional cpd. may be added to the supercritical fluid. Pref. in methods (a) and (c) supercritical carbon dioxide is pressurised to 2000-4000 psi while its temp. is 50-80C.    ADVANTAGE -   The treatment does not adversely affect wetting or other physical characteristics of the lens ,can improve the hydrophilicity of a lens and can also provide a dry moulded lens. The supercritical fluid provides a non-toxic, recyclable extraction solvent.    (EP741637-B1)      The following are claimed: (a) a method of producing an optically clear contact lens by treating the lens with a supercritical fluid; (b) a method of dry releasing a contact lens from a mould in which the lens was moulded by treating the contact lens and mould with a supercritical fluid; and (c) a method of extracting incompletely polymerised materials from a contact lens by treating the lens with a supercritical fluid. Pref. the supercritical fluid is supercritical carbon dioxide, nitrous oxide, ethane or propane; supercritical carbon dioxide is most pref.. An additional cpd. may be added to the supercritical fluid. Pref. in methods (a) and (c) supercritical carbon dioxide is pressurised to 2000-4000 psi while its temp. is 50-80C.    ADVANTAGE -   The treatment does not adversely affect wetting or other physical characteristics of the lens ,can improve the hydrophilicity of a lens and can also provide a dry moulded lens. The supercritical fluid provides a non-toxic, recyclable extraction solvent.    (US6071439-A)      The following are claimed: (a) a method of producing an optically clear contact lens by treating the lens with a supercritical fluid; (b) a method of dry releasing a contact lens from a mould in which the lens was moulded by treating the contact lens and mould with a supercritical fluid; and (c) a method of extracting incompletely polymerised materials from a contact lens by treating the lens with a supercritical fluid. Pref. the supercritical fluid is supercritical carbon dioxide, nitrous oxide, ethane or propane; supercritical carbon dioxide is most pref.. An additional cpd. may be added to the supercritical fluid. Pref. in methods (a) and (c) supercritical carbon dioxide is pressurised to 2000-4000 psi while its temp. is 50-80C.    ADVANTAGE -   The treatment does not adversely affect wetting or other physical characteristics of the lens ,can improve the hydrophilicity of a lens and can also provide a dry moulded lens. The supercritical fluid provides a non-toxic, recyclable extraction solvent.    (CN1142209-A)      The following are claimed: (a) a method of producing an optically clear contact lens by treating the lens with a supercritical fluid; (b) a method of dry releasing a contact lens from a mould in which the lens was moulded by treating the contact lens and mould with a supercritical fluid; and (c) a method of extracting incompletely polymerised materials from a contact lens by treating the lens with a supercritical fluid. Pref. the supercritical fluid is supercritical carbon dioxide, nitrous oxide, ethane or propane; supercritical carbon dioxide is most pref.. An additional cpd. may be added to the supercritical fluid. Pref. in methods (a) and (c) supercritical carbon dioxide is pressurised to 2000-4000 psi while its temp. is 50-80C.    ADVANTAGE -   The treatment does not adversely affect wetting or other physical characteristics of the lens ,can improve the hydrophilicity of a lens and can also provide a dry moulded lens. The supercritical fluid provides a non-toxic, recyclable extraction solvent.    (US6180031-B1)      The following are claimed: (a) a method of producing an optically clear contact lens by treating the lens with a supercritical fluid; (b) a method of dry releasing a contact lens from a mould in which the lens was moulded by treating the contact lens and mould with a supercritical fluid; and (c) a method of extracting incompletely polymerised materials from a contact lens by treating the lens with a supercritical fluid. Pref. the supercritical fluid is supercritical carbon dioxide, nitrous oxide, ethane or propane; supercritical carbon dioxide is most pref.. An additional cpd. may be added to the supercritical fluid. Pref. in methods (a) and (c) supercritical carbon dioxide is pressurised to 2000-4000 psi while its temp. is 50-80C.    ADVANTAGE -   The treatment does not adversely affect wetting or other physical characteristics of the lens ,can improve the hydrophilicity of a lens and can also provide a dry moulded lens. The supercritical fluid provides a non-toxic, recyclable extraction solvent.