Method for forming a balloon mold and the use of such mold

A method of forming a small diameter inflatable member comprising:

• a) forming a mold having an inner molding chamber with a continuous molding surface therein having the shape and dimensions of the desired inflatable member by the steps of,
• forming a core member having a shape and dimensions which correspond to the shape and dimensions of inflatable members to be molded and having an inner passageway extending therein which is in fluid communication with an opening at an end of the core member,
• inserting an end of an elongated holding member into the opening in an end of the core member,
• disposing the core member with the elongated holding member inserted within an end thereof within the interior of a heat-formable tubular member having proximal and distal ends
• forming a mold by heating the heat-formable tubular member while applying a vacuum to the interior thereof to cause the heat-formable tubular member to be shaped about the core member and take the shape and dimensions of the exterior of the core member, and
• passing a solution through the inner passageway of the core member to thereby dissolve the core member to remove the core member from the interior of the mold;
• b) inserting a tubular plastic member within the molding chamber;
• c) subjecting the plastic tubular member to internal fluid pressure and heat so that the tubular plastic member inflates within the molding chamber, engages the continuous molding surface of the molding chamber and thereby takes on the shape and dimensions thereof;
• and
• d) cooling the shaped plastic tubular member to retain the desired shape of the balloon therein.