Application Description

Europe's premier specialist in flexible and semi-rigid high barrier films for the food industry, Wipak Gryspeert has developed a new and innovative film called Escofoam™ for thermoforming peelable trays.

The rigid coextruded film is identified by its expanded polyester base combined with an EVOH barrier layer, within a PE/EVOH/PE/PET expanded matrix which has DuPont Bynel® coextruded adhesive resin as a bonding agent.

ESCOFOAM™ has become the first film of its type ever to be launched on the market.

Several European food industry companies have already adopted it for applications such as chicken in breadcrumbs, fresh pasta and for sliced dried Grison meat by Switzerland's Del Maitre company.

Because of its superior formability, the ESCOFOAM™ film - now available in 350 and 500 microns - can be used for thermoforming trays with straight or tapered walls 35 to 60 mm in depth, without pre-heating or requiring special shape blocks with thickness distribution and mechanical characteristics at least equivalent to those of EPS or EPP trays. The material's accurate thermoforming behavior makes it possible to have precisely defined embossed logos or consumer information on the bottom of the tray.

The ESCOFOAM™ film can be processed over a range of temperatures around 110°/130°C on all standard thermoforming machines available on the market, including equipment designed for shaping flexible films. The bonding characteristics of DuPont Bynel® resins avoid any delamination of the structure when it is subjected to thermomechanical stresses created by the thermoforming process.

The EVOH layer gives ESCOFOAM™ excellent barrier properties against gases, vapour and aromas as well as the ability to contain liquids such as juices, which make it ideally suited for packing fresh meat, fish, poultry, delicatessen products and even deep-frozen foods as it also provides an efficient barrier to thermal transmission. The film can be cut easily, including into complex shapes, with non rounded angles and displays the same soft feel as EPS.

ESCOFOAM™ is available in four colours - white for ultra-fresh foods, 'sea blue' for fish and sea-foods, cream for poultry, black for fancy meals and exotic foods. It can be crumpled like paper for easy disposal and incinerated without generating chlorine fumes.

Packaging Division of the Finnish group Wihuri Oy, Winpak produces a complete range of flexible and semi-rigid high barrier coextruded and laminated materials, plain or pre-printed, for use on flow-pack, thermoforming and lidding machines. Wipak has 5 plants in Europe (Finland, Netherlands, UK and France) as well as Winpak (Canada and USA) with 9 production units.

Because DuPont cannot anticipate or control the many different conditions under which this information and/or product may be used, it does not guarantee the applicability or the accuracy of this information or the suitability of its products in any given situation. Users of DuPont products should make their own tests to determine the suitability of each such product for their particular purposes. The data listed herein falls within the normal range of product properties but they should not be used to establish specification limits or used alone as the basis of design.

Disclosure of this information is not a license to operate or a recommendation to infringe a patent of DuPont or others.