Polyimide balloon catheter and method of forming a balloon therefor

Claim 2

A dilatation balloon catheter comprising: a shaft having an inflation lumen extending therethrough from a proximal end to a distal end; and a thin-walled inflatable balloon at the distal end of the shaft, the balloon being in fluid communication with the inflation lumen and being defined by a wall having a wall thickness of less than about 0.001 inches, a substantial portion of which is formed by a plurality of layers of polyimide polymer material, including an innermost polyimide layer defining an inner surface of the balloon, and an outer layer of an anti-friction material having a thickness of no greater than about 1,500 Angstroms; wherein the balloon has a proximal section connected to the distal end of the shaft, an intermediate inflatable section, and a distal section.

Claim 3

The dilatation balloon catheter of claim 1 wherein the balloon has a wall thickness of about 0.0003 inches.

Claim 4

The dilatation balloon catheter of claim 1 wherein the anti-friction material is a Paralene C polymer.

Claim 5

The dilatation balloon catheter of claim 1 wherein each layer of polyimide polymer material has a thickness of about 0.0001 inches.

Claim 6

The dilatation balloon catheter of claim 1 wherein the balloon has strength and tear resistance properties which are determined by the layers of polyimide polymer material.

Claim 7

The dilatation balloon catheter of claim 1 wherein the balloon has an essentially uniform wall thickness throughout its proximal, intermediate and distal sections.

Claim 8

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; and an low profile inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section, the intermediate section defining a balloon interior which is in fluid communication with the inflation lumen, the intermediate section being inflatable from an uninflated to an inflated state in response to fluid pressure supplied through the inflation lumen to the balloon interior so that the intermediate section has an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having a wall thickness of about 0.0003 inches and having strength and tear resistance properties determined by the polyimide layers.

Claim 9

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; and an low profile inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section, the intermediate section defining a balloon interior which is in fluid communication with the inflation lumen, the intermediate section being inflatable from an uninflated to an inflated state in response to fluid pressure supplied through the inflation lumen to the balloon interior so that the intermediate section has an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having a wall thickness of about 0.0003 inches and having strength and tear resistance properties determined by the polyimide layers.

Claim 10

The dilatation balloon catheter of claim 7 wherein the balloon has an essentially uniform wall thickness throughout its proximal, intermediate, and distal sections.

Claim 11

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate balloon section, and a distal section, the intermediate section having an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having a wall thickness of less than about 0.001 inches and having strength and tear resistant properties determined by the polyimide layers; and an outer layer of an anti-friction material over an outermost layer of polyimide.

Claim 12

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate balloon section, and a distal section, the intermediate section having an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having a wall thickness of less than about 0.001 inches and having strength and tear resistant properties determined by the polyimide layers; and an outer layer of an anti-friction material over an outermost layer of polyimide.

Claim 13

The dilatation balloon catheter of claim 9 wherein the outer layer has a thickness of no greater than about 1,500 Angstroms.

Claim 14

The dilatation balloon catheter of claim 9 wherein the anti-friction material is a Paralene C polymer.

Claim 15

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section; the intermediate section defining a balloon interior which is in fluid communication with the inflation lumen, the intermediate section being inflatable from an uninflated to an inflated state in response to fluid pressure supplied through the inflation lumen to the balloon interior so that the intermediate section has an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having an essentially uniform wall thickness of about 0.0003 inches throughout its proximal, intermediate and distal sections.

Claim 16

A dilatation balloon catheter for angioplasty, the catheter comprising: an elongated flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section; the intermediate section defining a balloon interior which is in fluid communication with the inflation lumen, the intermediate section being inflatable from an uninflated to an inflated state in response to fluid pressure supplied through the inflation lumen to the balloon interior so that the intermediate section has an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having an essentially uniform wall thickness of about 0.0003 inches throughout its proximal, intermediate and distal sections.

Claim 17

A dilatation balloon catheter for angioplasty, the catheter comprising: an inflatable flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section; the intermediate section having an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having an essentially uniform wall thickness of less than about 0.001 inches throughout its proximal, intermediate and distal sections; and an outer layer of an anti-friction material over an outermost layer of polyimide.

Claim 18

A dilatation balloon catheter for angioplasty, the catheter comprising: an inflatable flexible shaft having an inflation lumen extending from a proximal end to a distal end; an inflatable balloon, a substantial portion of which is formed by a plurality of layers of polyimide, the balloon having a proximal section connected to the distal end of the shaft, an intermediate inflatable balloon section, and a distal section; the intermediate section having an outer diameter, when inflated, which is greater than the proximal section and the distal section; the balloon having an essentially uniform wall thickness of less than about 0.001 inches throughout its proximal, intermediate and distal sections; and an outer layer of an anti-friction material over an outermost layer of polyimide.

Claim 19

The dilatation balloon catheter of claim 13 wherein the outer layer has a thickness of no greater than about 1,500 Angstroms.

Claim 20

The dilatation balloon catheter of claim 13 wherein the anti-friction material is a Paralene C polymer.

Claim 23

The method of claim 16 wherein the wall thickness is about 0.0003 inches.

Claim 24

The method of claim 16 wherein the polyamine solution is formed from a diamine monomer and a dianhydride monomer.

Claim 25

The method of claim 16 wherein dissolving the substrate comprises: chemically dissolving the substrate.

Claim 26

The method of claim 16 wherein the substrate has a lower melting temperature than the wall, and wherein dissolving the substrate comprises melting the substrate.

Claim 27

The method of claim 16 wherein a portion of the substrate has an outer surface configuration which corresponds to a desired shape of the balloon in an inflated condition.

Claim 28

The method of claim 16 wherein a portion of the substrate has an outer surface configuration which corresponds to a desired shape of the balloon in a deflated condition.

Claim 29

The method of claim 16 and further comprising: performing a mechanical forming process on the layer of polyamine solution after depositing and prior to curing.

Claim 32

The method of claim 24 wherein the outer layer has a thickness of no greater than about 1,500 Angstroms.

Claim 33

The method of claim 24 wherein the anti-friction material is a Paralene C polymer.