Through ether linkage, is produced from the poly vinyl alcoholic derivative which possesses the suspension vinyl monomer reaction product unit which has been joined the hydrogel contact lens

摘要

A contact lens of a crosslinked, organic aprotic solvent insoluble, substantially transparent polymer of a derivative of a polyvinyl alcohol having a weight average molecular weight of at least about 2,000, containing an effective amount between about 0.1 and 90 percent, based on the number of hydroxyl groups on said polyvinyl alcohol, of a crosslinked addition reaction product of units of the formula CHEM in the presence or absence of a polymerizable vinylic monomer wherein R1 is a divalent aliphatic, cycloaliphatic, aryl, aralkyl or alkaryl group; A is -O-, -NH- or -NHCON(R sec )- where R sec is hydrogen or lower alkyl and A min is a direct bond; or A is a direct bond and A min is -O- or -O-CH2-; R2 is hydrogen or methyl; and R is hydrogen, methyl or -COOR4 where R4 is hydrogen or lower alkyl; with the proviso that if R2 is methyl, R3 is hydrogen; and wherein the polymerizable vinylic monomer, if present, is hydrophobic or is a mixture of hydrophobic and hydrophilic vinylic monomers in which mixture at least 50 % of vinyl monomers are hydrophobic.