METHOD AND APPARATUS FOR TRANSFERRING MATERIAL TO A FIBROUS WEB BY USING ELECTRIC FIELD

摘要

The invention relates to a method and apparatus for transferring material to a fibrous web by using an electric field with a processing apparatus (1), which is provided with at least one nip or treatment zone (N) established by opposing treatment elements (5, 2; 15, 16) for passing therethrough a web (W) to be treated. In the method, one of the opposing treatment elements (5, 2; 15) of the processing apparatus has its bearing surface, which at some point of the process is in contact with a web to be treated, constituting a first electrode. In the path or in the vicinity of a flow carrying a material to be applied is disposed at least one second electrode (11) for having the flowing material particles charged with a charging potential sufficient with respect to the electrode constituted by said bearing surface of one treatment element for having charged particles (13a) transferred directly or indirectly onto a surface of the fibrous web (W) for adherence thereto, the web being passed, along the particles, through the nip or treatment zone (N) for an enhanced bonding of the particles to the web.