PURPOSE: To provide a hydrophilic bridging copolymer which is suitable for the use of a contact lens and a medical purpose by copolymerizing N-[1-2-oxo-1- pyrrolidinyl)ethyl]acyl amide or the mixture thereof and a specific (meta)acrylic acid derivative in the presence of a bridging agent.
CONSTITUTION: This hydrophilic copolymer is constituted by copolymerizing a monomer shown by formula I (R is hydrogen or methyl) or the mixture of this monomer and a monomer shown by formula II (R1 is hydrogen or methyl; X is OCH2CH2OH, OCH2CH(OH)CH3, OCH2CH(OH)CH2OH, (OCH2CH2)3OH, (OCH2CH2)2OH, alkoxyl of OCH3-OC16H33, NH2, NHCH2CH(OH)CH3, N(C2H5)5 or a group of NH-tert-C4H9) by using a bridging agent in the presence of a radical initiator. At that time, such conditions are applied that the content ratio of monomers of formula I and II is 40-99.99wt.% (at least 5wt.% of a monomer of formula I is necessary) of the total mixture and a bridging agent having at least two olefinic double bonds is 0.01-60wt.% of the total monomer mixture.
BURAHOSURABU OBEREINNERU
DANA SOUTSUKOBAA
