| abstract |
The invention concerns a process for producing a security film, comprising:n a. forming a polymeric film substrate having first and second surfaces; b. plasma treating at least one surface of the polymeric film substrate using a modified atmosphere plasma treatment, wherein the modified atmosphere comprises at least one inert carrier gas and at least one functional material selected from: i. one or more oxidising fluids; ii. one or more reducing fluids; and iii. one or more polar fluids with the capacity to form ionic or covalent bonds with the at least one surface of the polymeric film substrate, wherein those oxidising fluids with a relative dielectric strength less than that of air, where present, are in the modified atmosphere in an amount less than 40% by weight or by volume; and c. contacting a foil with the at least one plasma treated surface of the polymeric film substrate such that the foil adheres to the polymeric film substrate. |