Polyurethane diacrylate compositions useful for contact lenses and the like
AssigneeTyndale Plains-Hunter, Ltd.
InventorsFrancis E. Gould, Christian W. Johnston
Life of this patent
Estimating the term…
Abstract
Polyurethane diacrylate compositions are obtained by reacting a diacrylate in the presence of from about 30 to about 95 weight percent of a hydrophilic polyurethane resin. The resulting products will form a hydrogel upon immersion in water and are permeable to gases, ions and other low molecular weight species. The hydrophilic polyurethane diacrylate compositions may be molded to form shaped products that are dimensionally stable after repeated exposure to boiling water and exhibit memory. The compositions are useful for making contact lenses and numerous forms of surgical devices, among other things.
Claims19
A contact lens comprising a hydrophilic polyurethane diacrylate composition which will form a hydrogel upon immersion in water and is permeable to gases, ions and other low molecular weight species, which composition is dimensionally stable and exhibits memory, said polyurethane diacrylate composition comprising from about 90 to about 65 weight percent of a hydrophilic polyurethane resin characterized by terminal hydroxyl groups and from about 10 to about 35 weight percent of a diacrylate.
A contact lens comprising a hydrophilic polyurethane diacrylate composition which will form a hydrogel upon immersion in water;
- is permeable to gases, ions and other low molecular weight species;
- is dimensionally stable and exhibits memory;
- obtained by the reaction of from about 10 to about 35 weight percent of a diacrylate having the formula:
- ##STR3## wherein R is selected from the group consisting of hydrogen and the methyl radical and n is a whole number, such that the average molecular weight of the diacrylate is no greater than 1586;
- in the presence of from about 90 to about 65 weight percent of a hydrophilic polyurethane resin.
A corneal prosthesis comprising a hydrophilic polyurethane diacrylate composition which will form a hydrogel upon immersion in water and is permeable to gases, ions and other low molecular weight species which composition is dimensionally stable and exhibits memory, said polyurethane diacrylate composition comprising from about 90 to about 65 weight percent of a hydrophilic polyurethane resin characterized by terminal hydroxyl groups and from about 10 to about 35 weight percent of a diacrylate.
Dependencies are inferred from the claim text.