Method of producing a multilayered prosthesis material and the material obtained

Claim 1

A method of producing a multilayered prosthesis material for use with a living body, said material showing mechanical compliance vis-a-vis soft body tissue and possessing biocompatibility, said method comprising the steps of (a) preparing a solution of a biocompatible polymer using a mixed solvent, the mixed solvent including as a first constituent a solvent in which said polymer is substantially dissolvable and as a second constituent a non-solvent in which said polymer is not substantially dissolvable, said solvent and said non-solvent being substantially miscible, and said solution being near the precipitation point of said polymer; (b) applying said solution to a substrate, thereby forming a coating of said solution on said substrate; (c) precipitating the polymer in said coating by evaporating only a portion of the solvent, the amount of evaporation being such that said solution reaches the precipitation point of said polymer, the precipitate forming a physically stable porous structure, and (d) repeating steps (a), (b) and (c) in sequential fashion to form a plurality of coatings on said substrate, thereby forming the multilayered prosthesis material, said material being usable as a prosthesis when removed from said substrate.

Claim 2

A method of producing a multilayered prosthesis material for use with a living body, said material showing mechanical compliance vis-a-vis soft body tissue and possessing biocompatibility, said method comprising the steps of (a) preparing a solution of a biocompatible polymer using a mixed solvent, the mixed solvent including as a first constituent a solvent in which said polymer is substantially dissolvable and as a second constituent a non-solvent in which said polymer is not substantially dissolvable, said solvent and said non-solvent being substantially miscible, and said solution being near the precipitation point of said polymer; (b) applying said solution to a substrate, thereby forming a coating of said solution on said substrate; (c) precipitating the polymer in said coating by evaporating only a portion of the solvent, the amount of evaporation being such that said solution reaches the precipitation point of said polymer, the precipitate forming a physically stable porous structure, and (d) repeating steps (a), (b) and (c) in sequential fashion to form a plurality of coatings on said substrate, thereby forming the multilayered prosthesis material, said material being usable as a prosthesis when removed from said substrate.