METHOD FOR CONTROLLING SURFACE CONTACT AREA OF A PAPER OR BOARD SUBSTRATE
The application relates to a method for controlling contact area of a paper or board substrate (13) by depositing a trace amount of particles (11) on the surface of said substrate, and to a paper or board substrate treated in this way. The use of electrostatic deposition of coating materials, e.g. calcium stearate, alkyl ketene dimer (AKD) gives improved control on contact and surface characteristics. The particles are deposited in an amount ranging form 10-5-100 g/m2.