Patent ID: 8535597

Claim:
A multi-step balloon forming process comprising providing a tubular parison of thermoplastic material expanding the tubular parison in a first expansion step to provide a partially expanded parison and expanding the partially expanded parison in a second expansion step, wherein the first expansion step is performed in a segmented mold form comprising: a multi-mating α-end segment having a cavity sized to receive a portion of said tubular parison and to define an α-end portion of the balloon, said multi-mating end segment further having a mating edge portion adapted to mate with an adjacent mold portion, and a first-expansion-step portion having a mating edge portion adapted to mate with said mating edge portion of the multi-mating α-end segment and having a cavity that receives a portion of the parison and defines a portion of a partially expanded configuration to which the parison is expanded in the first expansion step, and the second expansion step is performed in a segmented mold form comprising: said multi-mating α-end segment, and a second-expansion-step portion having a mating edge portion adapted to mate with said mating edge portion of the multi-mating α-end segment and having a cavity that receives the partially expanded parison and defines a portion of the balloon configuration to which the partially expanded parison is expanded in the second expansion step.