Multilayer medical devices
View Patent ↗A medical device includes at least four layers including a first material and a second material having a different stiffness than a stiffness of the first material, wherein at least one of the layers varies in thickness axially along the device.
1. A medical device, comprising:
an elongated member comprising
at least two first coextruded layers comprising a first material; and
at least two second coextruded layers comprising a second material having a different stiffness than a stiffness of the first material,
wherein at least one of the layers varies in thickness radially along the member, and the first and second layers alternate along a radial direction of the member.
2. The device of claim 1 , wherein the member is stiffer at a proximal end than at a distal end.
3. The device of claim 1 , wherein the layers extend substantially the length of the member.
4. The device of claim 1 , comprising at least five layers.
5. The device of claim 1 , comprising at least seven layers.
6. The device of claim 1 , comprising at least 13 layers.
7. The device of claim 1 , wherein the device has the same number of layers for substantially the entire length of the member.
8. The device of claim 1 , wherein the at least one of the layers varies in thickness for substantially the entire length of the member.
9. The device of claim 1 , wherein the at least one of the layers varies in thickness at more than the one selected portions of the member.
10. The device of claim 1 , wherein layers of different materials vary in thickness at different selected portions of the member.
11. The device of claim 1 , wherein layers of different materials vary in thickness at about the same selected portion of the member.
12. The device of claim 1 , wherein the first and second materials comprise block copolymers including common block moieties.
13. The device of claim 12 , wherein the block moieties are amide segments and tetramethylene glycol segments.
14. The device of claim 1 , wherein the first and/or second material is selected from a group consisting of thermoplastic polyamides, thermoplastic polyesters, and thermoplastic elastomers.
15. The device of claim 1 , wherein the first and/or second material is a blend of polymers.
16. The device of claim 1 , in the form of a tube.
17. The device of claim 1 , in the form of a catheter shaft.
18. The device of claim 1 , in the form of guide wire.
19. The device of claim 1 , wherein the device is an extruded device.