Patent ID: 11319672

Abstract:
The present invention relates to a method for production of product comprising a first ply, the method comprising the steps of: providing a fibrous suspension comprising fibers; providing said fibrous suspension to a porous medium to form a substrate comprising fibers; providing a first additive suspension comprising a first strengthening agent, wherein the first strengthening agent is microfibrillated cellulose; providing a second additive suspension comprising at least one retention agent and/or at least one drainage agent; dewatering said substrate on said porous medium; performing additive addition to said substrate during said dewatering of said substrate on said porous medium, wherein the additive addition is performed when the substrate has a dry content of less than 20 weight-%, preferably less than 10 weight-%, most preferably less than 7 weight-%, and wherein the additive addition comprises adding at least a layer of said first additive suspension and a layer of said second additive suspension to said substrate by means of multilayer curtain coating, and further dewatering and drying said substrate after said dewatering on said porous medium so as to provide said first ply. The invention also relates to a paper, board or non-woven product obtainable by the method.