Nonwoven vascular prosthesis and process for its production

1 . A nonwoven vascular prosthesis ( 1 ) with pleats ( 3 ) in the vessel wall ( 2 ).

2 . The nonwoven vascular prosthesis ( 1 ) wherein the pleats ( 3 ) are in the form of waves.

3 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the vessel wall ( 2 ) is porous and may be sealed using a resorbable impregnating agent if required.

4 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the vessel wall ( 2 ) is formed from a web, particularly a sprayed web.

5 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the vessel wall ( 2 ) is made from polyurethane.

6 . The nonwoven vascular prosthesis as claimed in claim 5 , wherein the polyurethane is a thermoplastic polyurethane, particularly a polyurethane that is soluble in a solvent.

7 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the pleats ( 3 ) have grooves ( 5 ), which preferably run helically along the vessel wall ( 2 ).

8 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein furrows, particularly grooves ( 5 ), are formed by constricted zones in the pleats ( 3 ).

9 . The nonwoven vascular prosthesis as claimed in claim 8 , wherein the vessel wall ( 2 ) in the region of the furrows ( 5 ) is compacted, particularly by constricted zones.

10 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the internal diameter of the prosthesis measures 2 to 40 mm, and particularly 4 to 12 mm.

11 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the thickness of the vessel wall ( 2 ) measures 0.2 to 1 mm, and particularly 0.4 to 0.6 mm.

12 . The nonwoven vascular prosthesis as claimed in claim 1 , wherein the pleats ( 3 ) have a groove depth of 0.2 to 1 mm, and particularly 0.4 to 0.6 mm.

13 . A process for producing the pleated, nonwoven vascular prosthesis as claimed in claim 1 , wherein the vessel wall is formed on a rod-shaped core having a corrugated surface corresponding to the pleats.

14 . The process as claimed in claim 15 , wherein a rod-shaped core having a helically encircling, corrugated construction on its surface is used.

15 . The process as claimed in claim 13 , wherein a prefabricated, unpleated, nonwoven vascular prosthesis is pushed onto the rod-shaped core to produce the pleats and the pleats are formed in particular by heat treatment, which causes a reduction in size of the cross-section.

16 . The process as claimed in claim 13 , wherein the prefabricated nonwoven vascular prosthesis on the rod-shaped core is constricted in the wave troughs of the corrugated surface, and the constricted zones are fixed in place.

17 . The process as claimed in claim 13 , wherein a prefabricated vascular prosthesis, that has been reversibly pre-stretched in the cross-section, is pushed onto the rod-shaped core and shrunk onto it.

18 . The process as claimed in claim 13 , wherein a slippery intermediate layer, in particular a film, is applied to the rod-shaped core, in particular between the rod-shaped core and the prefabricated vascular prosthesis.

19 . The process as claimed in claim 13 , wherein the prosthesis is produced with pleats by spraying a solution of polyurethane onto the rod-shaped core to form a sprayed web with a corrugated surface.

20 . The process as claimed in claim 13 , wherein a core, having a corrugated surface and a cross-section that can be reduced in size, is used; the cross-section of the core can be reduced to facilitate removal of the pleated vascular prosthesis.

21 . The process as claimed in claim 13 , wherein the corrugated surface of the core is formed by a helix, which is wound onto a rod, and which is preferably removable in the lengthwise direction.