Method and apparatus for producing a nanostructured or microstructured foil by extrusion coating or extrusion casting

A method for producing a microstructured thermoplastic polymer coating on a carrier foil, the coating comprising at least one microstructured surface area, said method comprising:

• providing an extrusion coating roller for an industrial polymer extrusion coating process using a thermoplastic polymer;
• applying a surface comprising a microstructured non-thermoplastic polymer foil on the said extrusion coating roller, thereby forming a microstructured extrusion coating roller;
• maintaining the temperature of the said microstructured extrusion coating roller below the solidification temperature of the said thermoplastic polymer;
• moving the carrier foil at a fixed velocity between the microstructured extrusion coating roller and a counter pressure roller by rotating the microstructured extrusion coating roller at a fixed rotational velocity;
• and
• continuously applying a melt of said thermoplastic polymer between the said moving carrier foil and the said rotating microstructured extrusion coating roller, whereby said thermoplastic polymer melt is solidified upon contact with said microstructured extrusion coating roller maintained at a temperature below the solidification temperature of the said thermoplastic polymer melt thereby forming a solid microstructured thermoplastic polymer coating on said carrier foil.

A method for producing a microstructured amorphous thermoplastic polymer foil comprising at least one microstructured surface area, said method comprising:

• providing an extrusion roller for an industrial polymer extrusion casting process using a thermoplastic polymer;
• applying a surface comprising a microstructured non-thermoplastic polymer foil or coating on the said extrusion roller, thereby forming a microstructured extrusion roller;
• maintaining the temperature of the said microstructured extrusion roller below the solidification temperature of the said thermoplastic polymer;
• and
• continuously applying a melt of said thermoplastic polymer between the said microstructured extrusion roller and a counter pressure roller, wherein the microstructured extrusion roller is rotated at a fixed rotational velocity, whereby said thermoplastic polymer melt is solidified upon contact with said microstructured extrusion roller maintained at a temperature below the solidification temperature of the said thermoplastic polymer melt, thereby forming a solid microstructured thermoplastic polymer foil.