Treatment of fibrous material

摘要

A process for making a multi-ply consolidated dry-formed fibrous web having at least three plies, the outer plies are impregnated with a stiffening agent (e.g. starch) and the intermediate plies are impregnated with a sizing agent (e.g. wax/rosin size) to render them impervious to the stiffening agent. After the web has been consolidated by hot moist pressing, its outer surfaces may be further sized and hot moulded.