Patent ID: 7264458

Claim:
Apparatus for forming a medical device balloon, comprising a heating system for applying heat to at least one surface of a tubular parison having inner and outer surfaces, and a pressurization system for applying relative pressure to the inner surface of the parison, the combined heat and pressure being effective to expand the parison to form said balloon, wherein the heating system is configured to apply heat differentially to predetermined parison initiation zone and remainder zone locations on the parison so that the initiation zone location is heated to a higher temperature than the remainder zone location for at least an initiation time period encompassing the initiation of blowing of the parison, the apparatus further comprising a mold-form configured in the form of the balloon, and wherein the heating system comprises a plurality of heaters associated with the mold-form to apply localized heating of the mold, and a control system for operating the heaters, at least one said heater being separately controlled relative to the remainder thereof to produce an initiation zone in the mold in which the mold surface is at a higher temperature than the temperature of the remainder of the mold when initiation of balloon blowing occurs.