Patent ID: 6998447
Filing Date: 2006-02-14
Classification: A61L,C08F

Abstract:
1. A method for the production of a hydrophilic resin which comprises preparing a mixture solution of a water-soluble unsaturated monomer or monomer mixture containing 50 mol % or greater of aciylic acid partially or completely neutralized in an amount of 30 to 100 mol % to form an alkali metal and/or ammonium salts, 1 to 1,000 ppm of β-hydroxy propionic acid or a salt thereof and, optionally, a first cross-linking agent, polymerizing the mixture solution, drying the gel polymer thus obtained, and then cross-linking a surface region of the polymer by treating said polymer with a second cross-linking agent having at least two groups capable of reacting with a functional group within the molecular unit of said polymer.