Patent ID: 8007638

Claim:
A method of manufacturing a cellulosic sheet having at least one of hydrophobic and oleophobic properties, the method comprising (i) depositing a stock of cellulosic fibres onto at least one forming fabric at an impingement zone and forming a web therefrom in a formation process; (ii) combining a water-based composition comprising an adhesion promoter, an organic nanoparticulate polymer and a fluorocarbon with the web at a preselected combination stage prior to a heating stage at which the web is subjected to a temperature exceeding 60° C., wherein in the water-based composition the adhesion promoter is an organofunctional silane, the organic nanoparticulate polymer is selected from nanowaxes of polyethylene or polypropylene, and prepolymers of a condensated silane, and the fluorocarbon is selected from the group consisting of a fluoroacrylate and a fluoralkyl-polyurethane copolymer; and (iii) heat-curing the composition with the web during a drying process.