Laser bonding of angioplasty balloon catheters

• US 5,501,759 A
• Filed: 09/12/1994
• Issued: 03/26/1996
• Est. Priority Date: 11/29/1991
• Status: Expired due to Term

• Current Assignee: Schneider Electric SE
• Original Assignee: Schneider Electric SE
• Inventors: Forman, Michael R.
• Primary Examiner(s): Barry, Chester T.
• Application Number:
  US08/304,413
• Time in Patent Office: 561 Days
• Field of Search: 156/272.8, 156/86, 219/121.64
• US Class Current: 156/272.8
• CPC Class Codes: A61M 2025/1031 Surface processing of balloon members, e.g. coating or deposition; Mounting additional parts onto the balloon member's surface
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 25/1034 Joining of shaft and balloon
• CPC Class Codes: B29C 2035/0822 using IR radiation
• CPC Class Codes: B29C 65/1616 Near infrared radiation [NIR], e.g. by YAG lasers
• CPC Class Codes: B29C 65/1619 Mid infrared radiation [MIR], e.g. by CO or CO2 lasers
• CPC Class Codes: B29C 65/1622 Far infrared radiation [FIR], e.g. by FIR lasers
• CPC Class Codes: B29C 65/1635 at least passing through one of the parts to be joined, i.e. laser transmission welding
• CPC Class Codes: B29C 65/1654 scanning at least one of the parts to be joined
• CPC Class Codes: B29C 65/1661 scanning repeatedly, e.g. quasi-simultaneous laser welding
• CPC Class Codes: B29C 65/1664 making use of several radiators
• CPC Class Codes: B29C 65/1667 at the same time, i.e. simultaneous laser welding
• CPC Class Codes: B29C 65/1683 coated on the article
• CPC Class Codes: B29C 65/1687 making use of light guides
• CPC Class Codes: B29C 65/68 using auxiliary shrinkable elements
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/3452 Making complete joints by combining partial joints
• CPC Class Codes: B29C 66/53241 said articles being tubular and said substantially annular single elements being of finite length relative to the infinite length of said tubular articles making T-shaped pieces by joining tubular articles B29C66/52241
• CPC Class Codes: B29C 66/5344 said single elements being substantially annular, i.e. of finite length, e.g. joining flanges to tube ends B29C66/5346 takes precedence
• CPC Class Codes: B29C 66/612 Making circumferential joints
• CPC Class Codes: B29C 66/63 : Internally supporting the article during joining B29C66/49 takes precedence
• CPC Class Codes: B29C 66/65 : with a relative motion between the article and the welding tool B29C65/10, B29C65/12 take precedence
• CPC Class Codes: B29C 66/652 : moving the welding tool around the fixed article
• CPC Class Codes: B29C 66/71 : characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/73921 : characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29C 66/80 : General aspects of machine operations or constructions and parts thereof
• CPC Class Codes: B29K 2023/00 : Use of polyalkenes or derivatives thereof as moulding material
• CPC Class Codes: B29K 2067/00 : Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2067/003 : PET, i.e. poylethylene terephthalate
• CPC Class Codes: B29K 2075/00 : Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 : Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2079/08 : PI, i.e. polyimides or derivatives thereof
• CPC Class Codes: B29K 2995/0049 : Heat shrinkable
• CPC Class Codes: B29K 2995/0069 : non-permeable
• CPC Class Codes: B29L 2022/022 : Balloons
• CPC Class Codes: B29L 2031/7542 : Catheters
• CPC Class Codes: B29L 2031/7543 : Balloon catheters

Abstract

A process for assembling a balloon catheter involves selectively concentrating laser energy along an annular fusion bond site at contiguous surface portions of a length of catheter tubing and a shaft or neck portion of a dilatation balloon. The laser energy wavelength, and the polymeric materials of the balloon and catheter, are matched for high absorption of the laser energy to minimize conductive heat transfer in axial directions away from the bond site. This minimizes crystallization and stiffening in regions near the bond site, permitting fusion bonds to be located close to the proximal and distal cones of the dilatation balloon while preserving the soft, pliant quality of the cones. The disclosure further is directed to an embodiment of a balloon catheter assembled according to the process.

Claims

1. A process for forming a fluid tight seal between a polymeric body and a polymeric dilatation member surrounding the body, comprising the steps of:

positioning a dilatation member of polymeric material along and in surrounding relation to a body of polymeric material, with the dilatation member and body aligned to place a first surface portion of the dilatation member and a second surface portion of the body in a contiguous and confronting relation, wherein the polymeric materials forming the body and the dilatation member have non-uniform energy absorption spectra that include high absorptivity wavelength bands, and wherein at least one of the high absorptivity wavelength bands of the polymeric material forming the body and at least one of the high absorptivity wavelength bands of the polymeric material forming the dilatation member overlap one another in at least one range of overlapping wavelengths;

selecting a monochromatic energy wavelength that is contained within at least one of the overlapping wavelength ranges;

generating substantially monochromatic energy at said selected monochromatic energy wavelength;

controllably directing the monochromatic energy onto the body and the dilatation member to concentrate the monochromatic energy in a narrow bond site circumscribing the body and running along the interface of the first and second surface portions, thus to melt the polymeric materials along said bond site and the immediate region thereof; and

allowing the previously melted polymeric material to cool and solidify to form a fusion bond between the body and dilatation member.

2. The process of claim 1 wherein:

said interface of the first and second surfaces is annular, and the step of directing the monochromatic energy includes focusing the beam to position a focal area of the beam substantially at the interface, and moving the focal area, relative to the body and the dilatation member, in an annular path along the interface to define said bond site.

3. The process of claim 2 wherein:

the step of moving the focal area includes mounting the body and dilatation member substantially concentrically on an axis, and rotating the body and the dilatation member about the axis while maintaining the beam stationary.

4. The process of claim 3 wherein:

the focal area is circular and has a diameter of about 0.10 inches, and wherein the power of the laser is in the range of from 1-10 watts.

5. The process of claim 4 wherein:

the body and dilatation member are rotated at a speed of about 400 rpm for a duration in the range of from about 0.5 to about 3 seconds.

6. The process of claim 2 wherein:

the step of rotating the focal area relative to the body and dilatation member includes mounting the body concentrically about an axis, and optomechantcally rotating the beam about the axis while maintaining the body and dilatation member stationary.

7. The process of claim 2 wherein:

the monochromatic energy is laser energy having a wavelength in the far infrared range.

8. The process of claim 7 wherein:

the wavelength of the laser energy is approximately 10.6 micrometers.

9. The process of claim 1 wherein:

the step of directing the monochromatic energy includes providing multiple optical carriers arranged generally radially about the body and the dilatation member, and providing the monochromatic energy to the optical carriers simultaneously whereby the energy is directed in multiple beams that penetrate the body and dilatation member assembly at least to the interface.

10. The process of claim 9 wherein:

the multiple beams overlap one another at the interface.

11. The process of claim 10 wherein:

the monochromatic energy comprises laser energy in the near infrared range.

12. The process of claim 11 including the further step of:

prior to positioning the polymeric dilatation member, coating at least one of said first and second surfaces with a polymeric film highly absorbent of energy in the near infrared range of wavelength.

13. The process of claim 1 including the further step of:

positioning a polymeric shrink fit member in surrounding relation to the dilatation member and body, before said step of directing the monochromatic energy.

14. The process of claim 13 including the further step of:

removing the polymeric shrink fit member, following the step of allowing the melted polymeric material to cool and solidify.

15. The process of claim 1 wherein:

the body is a length of catheter tubing, and the dilatation member is a catheter balloon positioned along a distal end region of the catheter tubing and including proximal and distal neck portions, a medial region having a diameter substantially larger than that of the neck portions, and proximal and distal tapered conical regions between the medial region and respective neck regions; and

wherein the step of directing the monochromatic energy includes forming the bond site along the interface between the distal neck and the catheter tubing, separated from the distal tapered conical region by an axial distance of less than 0.030 inches.

16. The process of claim 1 wherein:

the polymeric material forming the body is selected from a group of polymeric materials consisting of;

polyesters, polyolefins, polyamides, thermoplastic polyurethanes and their copolymers.

17. The process of claim 1 wherein:

the polymeric material forming the dilatation member is selected from a group of polymeric materials consisting of;

polyethylene terephthalate, nylon, polyolefin, and their copolymers.

18. The process of claim 1 wherein:

the polymeric material forming the body consists essentially of polyester, the polymeric material forming the dilatation member consists essentially of polyethylene terephthalate, and the selected monochromatic energy wavelength is about 10.6 microns.

19. The process of claim 1 wherein:

the polymeric material forming the body consists essentially of either polyethylene or polypropylene, the polymeric material forming the dilatation member consists essentially of either polyethylene or polypropylene, and the selected monochromatic energy wavelength is approximately 3.4 microns.

20. A process for forming a fluid tight seal between a polymeric length of catheter tubing and a polymeric dilatation balloon surrounding the catheter tubing, comprising the steps of:

selecting a length of catheter tubing formed of a first polymeric material and a dilatation balloon formed of a second polymeric material, wherein the first and second polymeric materials have respective first and second non-uniform energy absorption spectra with respective first and second high absorptivity wavelength bands, and wherein at least one of the first wavelength bands overlaps at least one of the second wavelength bands to define at least one region of overlap in which both of the first and second energy absorption spectra exhibit high absorptivity;

positioning the polymeric dilatation balloon along and in surrounding relation to the length of polymeric catheter tubing, to align the dilatation balloon and the catheter tubing to place a first surface portion of the dilatation balloon and a second surface portion of the catheter tubing in a contiguous and confronting relation;

selecting a monochromatic energy wavelength that is contained within said at least one region of overlap;

generating substantially monochromatic energy at said selected monochromatic energy wavelength;

controllably directing the monochromatic energy onto the catheter tubing and the dilatation balloon to concentrate the monochromatic energy in a narrow bond site circumscribing the catheter tubing and running along the interface of the first and second surface portions, to melt the polymeric materials only along the bond site and the immediate region thereof; and

allowing the previously melted polymeric materials to cool and solidify to form a fusion bond between the catheter tubing and the dilatation balloon.

21. The process of claim 20 wherein:

the first polymeric material is selected from a group of polymeric materials consisting of;

polyesters, polyolefins, polyamides, thermoplastic polyurethanes and their copolymers.

22. The process of claim 20 wherein:

the second polymeric material is selected from a group of polymeric materials consisting of;

polyethylene terephthalate, nylon, polyolefin, and their copolymers.

23. The process of claim 20 wherein:

the first polymeric material consists essentially of polyester, the second polymeric material consists essentially of polyethylene terephthalate, and the selected monochromatic energy wavelength is approximately 10.6 microns.

24. The process of claim 20 wherein:

the first polymeric material consists essentially of either polyethylene or polypropylene, the second polymeric material consists essentially of either polyethylene or polypropylene, and the selected monochromatic energy wavelength is approximately 3.4 microns.

25. The process of claim 20 wherein:

said interface of the first and second surfaces is annular, and the step of directing the monochromatic energy includes focusing a beam of the monochromatic energy to position a focal area of the beam substantially at the interface, and moving the focal area, relative to the catheter tubing and dilatation balloon, in an annular path along the interface to define said bond site.

26. The process of claim 25 wherein:

the step of moving the focal area includes mounting the catheter tubing and the dilatation balloon substantially concentrically on an axis, and rotating the catheter tubing and the dilatation balloon about the axis while maintaining the beam stationary.

27. The process of claim 25 wherein:

the step of rotating the focal area relative to the catheter tubing and dilatation balloon includes mounting the body concentrically about an axis, and optomechanically rotating the beam about the axis while maintaining the catheter tubing and dilatation balloon stationary.

28. The process of claim 20 wherein:

the step of directing the monochromatic energy includes providing multiple optical carriers arranged generally radially about the catheter tubing and the dilatation balloon, and providing the monochromatic energy to the optical carriers simultaneously whereby the monochromatic energy is directed in multiple beams that penetrate the dilatation balloon at least to said interface.

29. The process of claim 20 wherein the monochromatic energy comprises laser energy in the near infrared range, and including the further step of:

prior to positioning the polymeric dilatation balloon, coating at least one of the first and second surfaces with a polymeric film highly absorbent of energy in the near infrared range.

30. The process of claim 20 including the further step of:

positioning a polymeric shrink-fit member in surrounding relation to the dilatation balloon and the catheter tubing, before said step of controllably directing the monochromatic energy.

31. The process of claim 30 including the further step of:

removing the polymeric shrink-fit member, following the step of allowing the previously melted polymeric materials to cool and solidify.

32. A process for forming a fluid tight seal between a polymeric body and a polymeric dilatation member surrounding the body, comprising the steps of:

positioning a dilatation member of polymeric material along and in surrounding relation to a body of polymeric material, with the dilatation member and body aligned to place a first surface portion of the dilatation member and a second surface portion of the body in a contiguous and confronting relation, wherein the polymeric materials forming the body and the dilatation member have non-uniform energy absorption spectra that include high absorptivity wavelength bands, and wherein at least one of the high absorptivity wavelength bands of the polymeric material forming the body and at least one of the high absorptivity wavelength bands of the polymeric material forming the dilatation member overlap one another in at least one range of overlapping wavelengths;

selecting a monochromatic energy wavelength that is contained within the at least one range of overlapping wavelengths;

generating substantially monochromatic energy at said selected monochromatic energy wavelength and at a laser power of less than about 10 watts;

controllably directing the monochromatic energy onto the body and the dilatation member to concentrate the monochromatic energy in a narrow bond site circumscribing the body and running along the interface of the first and second surface portions, thus to melt the polymeric materials along said bond site and the immediate region thereof; and

allowing the previously melted polymeric material to cool and solidify to form a fusion bond between the body and dilatation member.

33. The process of claim 32 wherein:

said substantially monochromatic energy is generated at a laser power in the range of about 3-4 watts.