A well known film producer of medical films has
selected a copolyester to produce films that have
better barrier properties as well as better clarity.
Tekniflex PGA and PGOA films are based on multi-layer
lamination constructions and used in blister packaging
applications for medical devices or drug product/device
combinations. Besides, copolyester films can have
good thermoformability. Eastar copolyester from
Eastman Chemical offers excellent thermoforming
properties for often complex medical trays and
is unaffected by irradiation (Gamma or e-beam).
The radiation is absolutely essential for medical
products to obtain the required sterilized level
of protection. The final package also offers good
physical protection due to the material's stiffness
Thermoplastic Elastomer (TPE) films
have been known to offer flexibility as well as
stretchability. Several types of TPES can be converted
into films, but the films that provide best breathability
are the ones produced from Polyester type of TPE,
more so from Ether type of Polyester TPE.
Breathable TPE films offer advantages of smoother
feel, higher permeability to perspiration and
thus higher comfort as compared to vinyls and
rubber latex products such as gloves used in the
medical field. When laminated, these film structures
find usage in garments in operating rooms as well
as wound dressings.
The types of soft segment in TPE structure can
introduce the breathability. The base polyether
segment is commonly made of polyethylene oxide
or propylene oxide block copolymers. The molecular
weight of softer segment also influences the breathability,
with higher molecular weight increasing breathability.
Breathable TPE films can be extruded as monolayer
films and can also be made by solution casting
process. However, extrusion process is more commonly
employed as it is more economical and free from
pollution. Only very soft grades are extremely
difficult to produce by melt extrusion process.
They have to be manufactured by solution casting
process. Blown extrusion film process is more
preferred compared to extrusion cast process.