Method of making a catheter balloon

A method of making a catheter balloon having a working length, proximal and distal tapered sections at either end of the working length, and proximal and distal skirt sections for securing the balloon to a catheter shaft, at least one of the proximal and distal skirt sections being a thinned skirt section, comprising:

• a) placing tubing in a balloon mold having a first portion with an interior surface which corresponds to the desired form of the working length and tapered sections of the balloon, and having a skirt portion for forming the thinned skirt section of the balloon, the skirt portion having an inner diameter which is larger than an outer diameter of the thinned skirt section of the balloon, and having an intermediate portion between the skirt portion and the first portion with an inner diameter smaller than the inner diameter of the skirt portion;
• b) expanding the tubing in the balloon mold to form the balloon having a radially enlarged skirt section, and an intermediate section between the radially enlarged skirt section and the tapered section adjacent thereto with a smaller outer diameter than the radially enlarged skirt section;
• and
• c) decreasing an inner diameter and the outer diameter of the radially enlarged skirt section, to form thinned skirt section.

A method of making a catheter balloon having a working length, proximal and distal tapered sections at either end of the working length, and proximal skirt section and a thinned distal skirt section for securing the balloon to catheter shaft, comprising:

• a) placing tubing in a balloon mold;
• b) expanding a first section of the tubing in the balloon mold to form the working length and the proximal tapered section and the distal tapered section of the balloon;
• and
• c) expanding a second section of the tubing to form a radially enlarged distal skirt section having an expanded outer diameter greater than an outer diameter of a distal end of the distal tapered section adjacent thereto, and decreasing the expanded outer diameter of the radially enlarged distal skirt section to form the thinned distal skirt section of the balloon, to form the balloon wherein a third section of tubing forms an intermediate section located between the distal tapered section and the radially enlarged distal skirt section, the third section having a smaller inner and outer diameter than the radially enlarged distal skirt section.