Film supplier Covestro develops solutions for wound dressings with a new rigid liner

Covestro has developed several material solutions, which facilitate a cost-efficient and simple production of wound dressings and wearables. The combination of a polypropylene (PP) liner with thermoplastic polyurethane (TPU) blown films, in particular, proved to be well suited to meet today's high demands for functionality and freedom of design. It also greatly reduces the generation of dust that can interfere with the clean manufacture of medical products at the customer's site.

Producing wound dressings and plasters, as well as medical wearables, involves a multi-stage process. Various coating and cutting processes can be employed to convert the products to achieve different desired functions. For instance, the liner material is often given a wavy cut (S-cutting) to allow clinicians to quickly remove the carrier when applying the dressing. In other cases, the outer edge of the carrier is not coated with adhesive and can therefore be easily lifted to remove it (finger lift).

Advantages of films with rigid PP liners

PP liners are relatively stiff and therefore offer sufficient strength, for example when gently creating windows without damaging the underlying layer, or when transferring the adhesive layer to the product. At the same time, they are flexible enough to optimally cover curved body parts such as hands, ankles and shoulders. PP carriers can also be combined with multilayer TPU films, for example to produce individual properties.

The blown film technology enables high speed production and enhanced efficiency. Blown TPU film on PP liner feature a wide range of surface qualities from silky to extra matt. In addition, various colors are offered in different skin tones for more discretion. Covestro has a range of TPU films with polyethylene (PE) liner and is developing paper carriers to offer a large choice of solutions to its customers.

The Platilon^® XM range of TPU extra matt blown films from Covestro is ideally suited for use in wound management as well as other medical applications: They are breathable and feel like a second skin with their soft texture. These types also have an extra matte surface. This offers lower friction with textiles and they also do not reflect much light. This allows them to be used as incision drapes in brightly lit operating rooms to eliminate distraction of surgeons as little as possible from their work.