Patent ID: 6464833
Filing Date: 2002-10-15
Classification: D21F,Y10S

Abstract:
A method of controlling the CD basis weight profile of a layered paper web comprising:(a) forming a layered paper web by using a layered headbox to deposit into a forming zone two or more aqueous suspensions of fibers, each of which corresponds to a different layering channel within the layered headbox; (b) providing each layering channel with an aqueous suspension of fibers through a tube bank comprising a multiplicity of tubes arranged in the cross-machine direction of the headbox; (c) measuring file cross-machine direction profile of at least one basis weight -related property of one or more of the layers in the web or the dried sheet, said basis weight-related property being selected from the group consisting of tensile strength, opacity and layer purity; and (d) in response to the measurement of the basis weight-related property profile, providing dilution water to selected tube bank tubes to locally adjust the basis weight of one or more layers.