Abstract: [Problems to be Solved] To provide highly hydrous contact lenses having a cellulose derivative as an essential component. [Means to Solve the Problems] The highly hydrous contact lens formed by exposing a pasty mixture containing a cellulose derivative, a polymerizable compound couplable to the foregoing cellulose derivative, and water to radiation.

Abstract: [Problems to be Solved] To provide highly hydrous contact lenses having a cellulose derivative as an essential component. [Means to Solve the Problems] The highly hydrous contact lens formed by exposing a pasty mixture containing a cellulose derivative, a polymerizable compound couplable to the foregoing cellulose derivative, and water to radiation.

Abstract: The invention relates to novel multifunctional organosiloxane monomers which can be represented by the general formulas: ##STR1## wherein, at least one of "X.sup.1 "-"X.sup.7 " is a group of the following structure: ##STR2## and its copolymerization with monofunctional organosiloxane monomers which can be represented by the general formulas: ##STR3## and alkyl and/or cyclic alkyl esters of acrylic, methacrylic acids and/or itaconate esters, and in some cases fluoroalkyl esters of acrylic, methacrylic acids and/or fluoroalkyl itaconate esters to produce excellent oxygen permeable hard contact lens material.Preferably, the copolymer includes cross-linking agents and wetting agents.Contact lenses manufactured from the materials can be easily machined and polished into hard contact lenses having solvent-resistance and sufficient permeabilities.