Abstract: (Semi-)continuous etching method for a fluoropolymer substrate (10) comprising steps of feeding (22) said substrate (10) in the form of a continuous ribbon wherein said substrate defines a primary surface (12), subjecting to at least one etching operations (2) a part of the primary surface (12) by means of an adhesion-promoting solution comprising a complex of an alkali metal in naphthalene, washing (4) the primary surface (12) wetted by the adhesion-promoting solution by means of a washing solution (42) comprising aqueous acetic acid/formic acid, and selectively separating a concentrated solution (24) of acetic acid/formic acid from the washing solution (42) by means of inverse osmosis operations (6, 8) at ? increasing pressures, and re-introducing at least a portion of the concentrated solution (24) of acetic acid/formic acid in the washing solution (42) to create a recirculation. The invention further relates to an etching plant.

Abstract: (Semi-) continuous etching method for a fluoropolymer substrate (10) comprising steps of feeding (22) said substrate (10) in the form of a continuous ribbon wherein said substrate defines a primary surface (12), subjecting to at least one etching operations (2) a part of the primary surface (12) by means of an adhesion-promoting solution comprising a complex of an alkali metal in naphthalene, washing (4) the primary surface (12) wetted by the adhesion-promoting solution by means of a washing solution (42) comprising aqueous acetic acid/formic acid, and selectively separating a concentrated solution (24) of acetic acid/formic acid from the washing solution (42) by means of inverse osmosis operations (6, 8) at ? increasing pressures, and re-introducing at least a portion of the concentrated solution (24) of acetic acid/formic acid in the washing solution (42) to create a recirculation. The invention further relates to an etching plant.