摘要 |
The lumen surface of tubing is modified by exposure to a gas plasma in a vacuum apparatus. A method and apparatus are disclosed whereby plasma treatment of the lumen surface, such as by deposition of a plasma polymerizate, may be achieved inside a continuous length of tubing. A gas such as a monomer vapor is caused to enter the lumen of the tubing through openings sequentially arranged at a periodic interval along the length of the tubing, and is excited to a plasma state concurrently as the tubing passes through a tubular reaction conduit having an inner diameter in occlusive contact with the tubing's outer diameter. Essentially crack-free plasma polymerizate coatings with thicknesses greater than 1000 angstroms are selectively deposited on the lumen wall of the continuous tubing. Plasma-modified tubing is prepared having usefulness in medical devices such as catheters, vascular grafts and enteral feeding tubes. |