Method of manufacturing implants
View Patent ↗A method of manufacturing a tubular medical implant, such as a stent, includes introducing a liquid polymer material into an axial lumen of an elongate metal tube, the metal tube having an inner wall defining the lumen; allowing the polymer material to solidify within the metal tube lumen, the solidified polymer forming a high friction surface in contact with the inner wall of the metal tube; securing the metal tube, including the solidified polymer material therein, to a collet of a laser etching system; and laser etching a predetermined pattern of openings in the metal tube.
1. A method of manufacturing a tubular medical implant, comprising, in the following order:
inserting an elongate polymer or pre-polymer member into a lumen of an elongate metal tube, the metal tube having an inner wall defining the lumen, wherein the polymer member is hollow and defines a polymer member lumen;
radially expanding the polymer member within the metal tube lumen to thereby increase a frictional force applied by the polymer member against the inner wall of the metal tube, wherein radially expanding the polymer member comprises heating the polymer member and increasing a pressure within the lumen of the heated polymer member;
securing the metal tube, including the expanded polymer member therein, to a collet of a laser etching system;
laser etching a predetermined pattern of openings in the metal tube;
reheating the polymer member;
axially stretching to thereby radially contract the reheated polymer member;
and removing the radially contracted polymer member from the metal tube lumen.
2. The method of manufacturing of claim 1 , wherein the polymer member is solid, and wherein radially expanding the polymer member comprises heating the polymer member, and axially compressing the heated polymer member.
3. The method of manufacturing of claim 1 , further comprising, after radially expanding the polymer member, and before laser etching the predetermined pattern of openings in the metal tube, annealing the polymer member to reduce or eliminate residual stress stored therein.
4. The method of manufacturing of claim 1 , further comprising, prior to inserting the polymer member into the metal tube lumen, applying a tie-layer of adhesive material to one or both of the inner wall of the metal tube and an outer surface of the polymer member.
5. The method of manufacturing of claim 1 , wherein inserting the elongate polymer member into the metal tube lumen comprises extruding the polymer member directly into the metal tube lumen.