METHODS AND SYSTEMS FOR LEACHING SILICON HYDROGEL OPHTHALMIC LENSES Russian patent published in 2010 - IPC B29D11/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of making ophthalmic lenses from silicon hydrogels. The method of removing unreacted components and diluents from an ophthalmic lens which contains silicon involves exposure of the said ophthalmic lens to a first aqueous solution containing approximately 5% or more of a first leaching agent which is in form of one or more agents selected from: fatty acid ethylene C_12-14 (E12E10) ethoxylated with ten oxides, dodecylsulphate (SDS), polyoxyethylene-2-ethylhexyl ether (EH-5), polypropylene glycol (PPG 425), ethyl alcohol and isopropyl alcohol, and where the first aqueous solution also contains 5% or more of a second leaching agent which is a surfactant Standamox CAW, heating said first aqueous solution and washing the lens through contact with the second aqueous solution until content of unreacted components and diluents in the lens falls below a given level.

EFFECT: lenses made using the disclosed method require little or no use of organic solvents, avoids use of highly flammable agents and makes easy removal of the lens from the mould.

80 cl