Abstract: A process is disclosed for the preparation of hydrogel contact lenses having improved mechanical properties, said process comprising polymerizing, in the presence of an azo type initiator, a monomer mixture comprising from 25% to 50% by weight of N-vinyl pyrrolidone, up to 5% by weight of methacrylic or acrylic acid, 0.1 to 1% by weight of 1,3,5-tris(propenoxy)-2,4,6-triazine (TPT), or perhydro-2,4,6,-triketo-1,3,5,-tris (propene-2)-1,3,5-triazine (T.T.P.T.), as a cross-linking monomer, the balance being essentially hydroxy alkyl acrylate or methacrylate, wherein the alkyl group is ethyl or propyl.
Abstract: Hydrogels are prepared by subjecting to poymerization conditions an aqueous admixture comprising a major amount of an organic monomer which is characterized by a polymerizable ethylenic group ##STR1## as illustrated by N,N-dimethylacrylamide, 2-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate or methoxytriethylene glycol methacrylate, and a minor amount of solubilized collagen. The reactants employed are at least partially soluble in the aqueous reaction medium. The hydrogels thus prepared are novel shaped articles having utility in the medical and cosmetic fields. Contact lenses of such hydrogels exhibit high water content, high oxygen permeability and good mechanical strength characteristics.
Abstract: A water-absorptive contact lens made of a copolymer comprising units of an ester of acrylic or methacrylic acid and at least one saccharide selected from D-galactose, D-glucose and D-mannose and units of at least one member selected from a hydrophilic monomer and a hydrophobic monomer, which has excellent oxygen permeability and affinity for the eye and can be worn continuously for a long period of time. The contact lens is prepared by polymerizing a monomer mixture containing an ester of acrylic or methacrylic acid with a ketalized saccharide and a hydrophilic monomer and/or a hydrophobic monomer, and after forming the resulting copolymer into a contact lens, if necessary, treating the copolymer having a shape of contact lens with an acid to convert the ketal groups into hydroxyl groups.
Abstract: Low N-vinyl lactam content copolymers are cross-linked with resonance free di(alkene tertiary amine) cyclic compounds to obtain biomedical devices, including soft contact lenses, which have good oxygen permeability and mechanical properties.
Type:
Grant
Filed:
November 12, 1981
Date of Patent:
April 3, 1984
Assignee:
Bausch & Lomb Incorporated
Inventors:
Richard C. Chromecek, Gary D. Friends, Lawrence Y. Wissman, Raymond A. Yourd, III
Abstract: N-vinyl lactam monomers and comonomers are cross-linked with resonance free di(alkene tertiary amine) cyclic compounds to obtain biomedical devices, including contact lenses, which have high oxygen permeability and good mechanical properties.
Type:
Grant
Filed:
November 12, 1981
Date of Patent:
March 13, 1984
Assignee:
Bausch & Lomb Incorporated
Inventors:
Richard C. Chromecek, Gary D. Friends, Lawrence Y. Wissman, Raymond A. Yourd, III
Abstract: Polymeric materials suitable for biomedical applications, particularly in making contact lenses, are formed by copolymerization and crosslinking of: (1) an amide of an unsaturated carboxylic acid such as acrylamide or methacrylamide; (2) an N-vinyl lactam such as N-vinyl pyrrolidone; (3) an ester of an unsaturated carboxylic acid such as a hydroxy-substituted ester of acrylic or methacrylic acid; (4) an unsaturated carboxylic acid such as acrylic or methacrylic acid; and (5) a hydrophobic monomer component comprising: (a) a fluorine-containing polymerizable monomer having a fluoroaliphatic side chain, such as fluoroalkyl acrylate or methacrylate, and (b) a non-fluorine-containing polymerizable hydrophobic vinyl monomer such as styrene; crosslinking with a crosslinking agent either being carried out during copolymerization or subsequently.
Abstract: Polymeric materials suitable for bio-medical applications, particularly in making contact lenses, are formed by copolymerization and crosslinking of: (1) an amide of an unsaturated carboxylic acid such as acrylamide or methacrylamide; (2) an N-vinyl lactam, such as N-vinyl pyrrolidone; (3) an ester of an unsaturated carboxylic acid, such as a hydroxy-substituted ester of acrylic or methacrylic acid; (4) an unsaturated carboxylic acid, such as acrylic or methacrylic acid; and (5) a polymerizable hydrophobic vinyl monomer, such as styrene; crosslinking with a crosslinking agent either being carried out during copolymerization or subsequently. The resulting polymeric materials may be machined to produce a contact lens form and then hydrated to form a hydrogel which is suitable for use as an extended wear contact lens.
Abstract: Biologically stabilized compositions are prepared by subjecting to polymerization conditions an aqueous admixture comprising from 50 to about 70 weight percent solubilized collagen and from about 30 to less than 50 weight percent of an organic compound which is characterized by a polymerizable ethylenic group (>C.dbd.C<) as illustrated by N,N-dimethylacrylamide, 2-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate or methoxytriethylene glycol methacrylate. The reactants employed are at least partially soluble in the aqueous reaction medium. The hydrogels thus prepared can be in the form of novel shaped articles having utility in the medical and cosmetic fields. Such hydrogels exhibit good biological stability, high water content, high oxygen permeability and sufficient mechanical strength characteristics to be useful as contact lenses.
Abstract: Cross-linked hydrophilic polymers, useful inter alia for the manufacture of contact lenses capable of absorbing water to a water content of 63 to 90% by weight while retaining excellent tensile strength contain hydrophilic units of N-vinyl-2-pyrrolidone, with optionally other hydrophilic monomers in minor amount, hydrophobic units of cycloalkyl acrylate, methacrylate or itaconate, and optionally other hydrophobic monomers, and units of a cross-linking agent. They may be made by polymerizing the monomers in the presence of a free radical generating catalyst. The polymer may then be shaped and hydrated.
Abstract: A hydrophilic polymer shaped article adapted for use as a soft contact lens is treated to provide at least on the surfaces thereof a modified, less hydrophilic polymeric structure inhibiting penetration by bacteria and proteins, whereby development of clouding and discoloration of the lens material during use is significantly retarded. Modification of the lens surfaces is effected by treatment of the lenses, either unhydrated or in a partially hydrated state, at a temperature ranging from room temperature to 100.degree. C. and for a time period of 1 to 24 hours, with a water-soluble mono- or poly-carboxylic acid selected from alpha-amino acids, such as arginine, cysteine, glycine and like acids, aliphatic dicarboxylic acids or aromatic dicarboxylic and tricarboxylic acids, such as malonic, maleic, glutaric, citraionic, itaconic acid and the like.