a laminate balloon comprising at least two layers of separately oriented thermoplastic polymer material , which are coextensive over the body of the balloon . the two layers may be made of different polymer materials , including an underlying layer made of a low compliant , high strength polymer , such as pet , and an overlying layer of a softer and more flexible polymer material relative to the first polymer material , such as a polyester - polyether block copolymer . the balloon structures have an additive burst pressure , meaning that they are stronger than a single - layer reference balloon corresponding to the underlying polymer layer . the balloons are characterized by a combination of flexibility and surface softness which allows catheters to track down into lesions relatively easily , puncture resistance , abrasion resistance and refoldability , in addition to low compliance and high burst strength . the balloons may be prepared with generally linear or with stepped compliance profiles . methods of preparation of such balloons are also disclosed .