Method for hydrogel surface treatment and article formed therefrom
AssigneeNovartis AG
InventorsRichard Carlton Baron, Qin Liu
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Abstract
A method of modifying the surface characteristics of a polymeric hydrogel, and a polymer article formed therefrom, without causing substantial swelling or distortion or the hydrogel. A preferred method includes photoinitating of the surface of the article with a benzophenone and grafting a macromer having a number-average molecular weight greater than 1000 in the presence of UV irradiation. The preferred article is a siloxane-containing hydrogel, especially a soft contact lens.
Claims16
A method of treating the surface of a polymeric article, comprising the steps of:
- (a) immersing a polymeric article in a first solution including a photosensitizer and at least one solvent for a predetermined time period;
- (b) removing said article from said first solution;
- (c) evaporating at least a portion of said solvent from said article;
- (d) placing said article in a second solution containing at least one macromer;
- and
- (e) applying radiation to said article for a period sufficient to cause at least a portion of said monomers or macromers to bond to the surface of said article,
- wherein said macromer has a size sufficiently large such that no substantial amount of macromer penetrates said article causing substantial distortion of said article.
A method of claim 10, wherein said macromer is a polyethylene oxide.
A method of claim 18, wherein said silicon-containing polymer is a polydimethylsiloxane.
A polymeric article having a surface with properties different from the bulk polymeric article material, said polymeric article comprising:
- (a) a polymeric article bulk material selected from the group consisting of siloxane-containing polymers;
- (b) a surface coating on said polymeric article bulk material, said surface coating including pendant groups formed by graft polymerization by surface photoinitiation with a benzophenone, said pendant groups being formed from one or more macromers having a size sufficiently large such that no substantial amount of macromer penetrates said lens causing substantial distortion of said article.
An article of claim 21, wherein said article is selected from the group consisting of contact lenses, intraocular lenses, implants, and ophthalmic agent delivery devices.
An article of claim 22, wherein said article is a soft contact lens.
Dependencies are inferred from the claim text.