Use of polymer alloys based on cellulose esters in contact ophthalmics, and contact lenses produced from the polymer alloys

摘要

Contact lenses prepared from a polymer alloy essentially free from low molecular weight plasticizers and which comprisesP P(A) 97- 80% by weight of one or more cellulose esters of one or more aliphatic carboxylic acids, andPP(B) 3-30% by weight of an aliphatic polymeric compound having ester moieties, carbonate moieties or both ester and carbonate moieties in the polymer chain and having an average molecular weight of 2,000 to 300,000, with less than 2% by weight of compounds having a molecular weight below 500.