Surface treatment of a polymeric stent
Methods of treating the polymeric surfaces of a stent with a fluid including a solvent for the surface polymer are disclosed.
1. A method for forming a stent, comprising,
providing a tube formed from a polymer material,
laser cutting the polymer tube to form a laser cut polymer tube including first and second struts, wherein the laser cutting forms an undesired portion on the first and second struts, wherein the undesired portion is one or more of a lower molecular weight material disposed over the first and second struts, cracks, sharp edges and imperfections on or adjacent to the first and second struts;
applying a solvent and/or abrasive to the laser cut tube to remove substantially all of the undesired portion from the laser cut tube; and
then removing the solvent and/or abrasive from the laser cut tube to form the stent.
2. The method for forming a stent of claim 1 , wherein the applying step further includes directing a nozzle towards only the undesired portion, the nozzle dispensing the solvent and the solvent comprises a fluid.
3. The method for forming a stent of claim 2 wherein the fluid is a gas.
4. The method for forming a stent of claim 2 wherein the fluid is a gas, the nozzle dispenses the gas and the abrasive, and the abrasive is particles dispersed within the gas.
5. The method for forming a stent of claim 2 wherein the fluid is a liquid.
6. The method for forming a stent of claim 2 wherein the fluid is a liquid, the nozzle dispenses the liquid and abrasive, and the abrasive is particles dispersed within the liquid.
7. The method for forming a stent of claim 1 wherein a solvent is applied, the laser cut tube is disposed within a circulating liquid comprising the solvent and a bore axis of the laser cut tube is arranged at an acute angle to a free stream fluid flow direction of the circulating solvent to cause a greater removal rate of the undesired portion disposed on or near the first strut than the second strut.