Method of forming a co-extruded balloon for medical purposes

• US 6,136,258 A
• Filed: 04/24/1995
• Issued: 10/24/2000
• Est. Priority Date: 04/26/1991
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Corporation
• Inventors: Roberts, George T., Wang, James C., Pederson, Brian A. Sr., Abele, John
• Primary Examiner(s): Timm, Catherine
• Application Number:
  US08/427,997
• Time in Patent Office: 2,010 Days
• Field of Search: 264/514, 264/515, 264/529, 264/530, 264/171.28, 156/244.13, 156/244.14, 156/244.19, 604/96, 606/194
• US Class Current: 264/514
• CPC Class Codes: A61B 2017/00783 Valvuloplasty
• CPC Class Codes: A61L 29/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61M 2025/1075 having a balloon composed of several layers, e.g. by coating or embedding
• CPC Class Codes: A61M 25/1029 Production methods of the balloon members, e.g. blow-moulding, extruding, deposition or by wrapping a plurality of layers of balloon material around a mandril
• CPC Class Codes: A61M 25/1034 Joining of shaft and balloon
• CPC Class Codes: A61M 25/1038 Wrapping or folding devices for use with balloon catheters
• CPC Class Codes: C08L 67/02 Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: Y10T 428/1334 Nonself-supporting tubular film or bag [e.g., pouch, envelope, packet, etc.]
• CPC Class Codes: Y10T 428/1393 Multilayer [continuous layer]

Abstract

A method of forming a balloon for medical purposes including co-extruding in a tubular shape a base structural layer of polyamides, polycarbonates, polyesters and copolymers thereof and a heat sealable layer of polyethylene and copolymers thereof. The tubular member is then biaxially oriented by inflating the tube with a gas to a predetermined central diameter greater then the initial diameter of the tube and simultaneously heating the inflated tube to a temperature sufficient to biaxially orient the base structural layer. The member is then cooled the inflated tubular member and then elevated in temperature for a second time to the biaxially orienting temperature. The twice-heated tube is allowed to cool and the gas is withdrawn whereby the tubular member will assume a generally tubular shape and the main structural layer will remain biaxially orientated and the heat sealable layer will not be biaxially orientated.

Claims

1. A method of manufacturing a medical catheter, the method comprising:

coextruding a first layer and a second layer to form a tube having an outside diameter, said first layer comprised of polyethylene terephthalate and said second layer comprised of a material selected from the group consisting of Nylon and polyethylene terephthalate;

simultaneously pressurizing and heating at least a region of said tube to inflate said region to an outer diameter greater than said outside diameter of said tube;

forming a balloon for medical purposes from said inflated region of said tube;

providing a catheter shaft having at least one lumen disposed therethrough; and

attaching said balloon to said catheter shaft so that said at least one lumen is in fluid communication with an interior region of said balloon.

2. The method recited in claim 1 wherein said coextruding step comprises coextruding three layers to form the coextruded tube.

3. The method recited in claim 1 wherein said first layer has a composition different than that of said second layer.

4. The method recited in claim 1 further comprising the step of heat setting said inflated region of said tube.

5. The method recited in claim 1 wherein said first layer comprises a toughened grade of polyethylene terephthalate.

6. The method recited in claim 3 wherein the second layer is comprised of polyethylene terephthalate.

7. The method recited in claim 6 wherein the second layer is polyethylene terephthalate.

8. The method recited in claim 1, wherein the first layer comprises a blend of polyethylene terephthalate and another material.

9. The method recited in claim 1, wherein the first layer is disposed radially outside the second layer.

10. The method recited in claim 9, wherein the first layer comprises a blend of polyethylene terephthalate and another material and the second layer is polyethylene terephthalate.