Less film produces stronger medical packaging

Philadelphia--When it comes to medical packaging, have you considered going from a 4-mil-gauge to a 3-mil-gauge film? Such a switch certainly would reduce the amount of material needed. But what about impact strength?

ShieLLD(TM), a new linear, low-density polyethylene (LLDPE) film from Perfecseal, a Bemis Co., provides the user with both benefits. When produced in a 3-mil gauge, the material demonstrates 150% more impact strength than conventional 4-mil LLDPE film, according to Bill Wetzel, product manager, new materials. At 4 mil, ShieLLD has 238% more impact strength than other types of 4-mil LLDPE--with 250% greater tear strength, Wetzel adds.

Wetzel also reports that the new material is formulated from resins made under a new catalyst technology for narrow or controlled molecular weight distribution of the polyethylene polymer. Since it can't be extruded using conventional film-extrusion equipment, Perfecseal has invested in specialized equipment, manufacturing processes, and technical expertise to process blown films.

"The ability to go from a 4-mil LLDPE to a 3-mil ShieLLD means a medical-device manufacturer will use less material per package, yet gain tear and impact strength," Wetzel notes. "This, in turn, results in packaging source reduction and lower shipping costs."

Header-bag packaging for large, bulky medical devices or heavy trays filled with supplies and instruments offers an example. The bag provides a breathable substrate so that gases formed during the sterilization process pass through and the bag will reseal to protect the sterilized device.