Italian extrusion specialist Amut is expanding its presence in the field of EVA processing for the production of photovoltaic solar panels.
On Amut lines, the sheet width can be from 1050 mm up to 2100 mm, with a thickness range from 0.3 to 0.8 mm.
EVA foil protects the photovoltaic cell, which encapsulates and wraps the silicon cells. The production process has to deliver a foil with the maximum light transmission and with the capacity to not cross-linking.
EVA foil enables a perfect sealing and a high adherence with the outer glass sheet and with the back-sheet. During vacuum lamination of the various elements with the silicon cells, the dimensional stability prevents deformations or shrinkages, says Amut.
The gravimetric dosing and extrusion/die units supplied, which have been developed for this application, can process both liquid and solid additives, thus ensuring an optimal melting of the polymer in order to give the foil the necessary resistance to UV rays and avoid the yellowing effect (which causes a lack of efficiency in energy production).
The calendar has three rolls with a special surface treatment to handle EVA material and independent drives. It is also equipped with a stabilisation unit. To control the cooling phase and reduce the tension at minimum level, the cooling phase must be progressive, explains the group. Therefore, the built-in thermoregulation system is essential for both extrusion and cooling processes.
The calendar is purpose-built to reduce deformation of the foil, with the option to emboss on one sheet layer allowing the adherence with the glass sheet and to laminate in-line a silicone paper sheet. The winding system can wind-up, directly in-line, the foil in reels or permit the insertion of an additional film sheet to separate and better protect the EVA foil.
