Patent ID: 6183599
Filing Date: 2001-02-06
Classification: D21F,D21H,Y10T

Abstract:
A process for the manufacture of a soft bathroom tissue product having a serpentine configuration and low sidedness, which process comprises:providing a moving foraminous support;providing a stratified headbox adjacent said moving foraminous support adapted to form a nascent web by depositing furnish upon said moving foraminous support, said stratified headbox having at least two plena;providing wet pressing means operatively connected to said moving foraminous support to receive said nascent web and for dewatering of said nascent web by overall compaction thereof;providing a Yankee dryer operatively connected to said moving foraminous support and said wet pressing means and adapted to receive and dry the dewatered nascent web;one plenum of said headbox being adapted to deposit a Yankee-dryer side stratum of furnish on said moving foraminous support such that, during drying of said nascent web, said Yankee-dryer side stratum will engage said Yankee dryer;another plenum of said headbox being adapted to deposit a distal stratum of furnish on said moving foraminous support such that, during drying of said nascent web, said distal stratum will be spaced from said Yankee dryer;supplying a furnish to said one plenum to form said Yankee-dryer side stratum comprising cellulosic papermaking fiber chosen from the group consisting of hardwood, softwood, and recycled fibers and cationic nitrogenous softener/debonder, and optionally, strength enhancing starch;supplying another furnish to said other plenum to form said distal stratum comprising cellulosic papermaking fiber chosen from the group consisting of hardwood, softwood, and recycled fibers, and cationic nitrogenous softener/debonder, and optionally, strength enhancing starch;forming a nascent web by depositing said one furnish and said other furnish on said moving foraminous support, controlling the overall concentration of cationic nitrogenous softener/debonder in a single-ply bathroom tissue product produced from said web to between about 1 to about 8 lbs/ton of said nascent web as measured on a dry fiber basis;the concentration of cationic nitrogenous softener/debonder in said Yankee-dryer side stratum being from about 15% to no more than 75% of the concentration of said cationic nitrogenous softener/debonder in the distal stratum;the concentration of strength enhancing starch in the Yankee-dryer side stratum being from at least about 1 to about 6 lbs/ton whenever the amount of hardwood in the distal stratum exceeds 25%;the concentration of strength enhancing starch in said distal stratum being no more than the greater of about 0.5 lbs/ton or 20% of the concentration of said strength enhancing starch in the Yankee-dryer side stratum whenever the amount of hardwood in the distal stratum exceeds 25%wet pressing said nascent web;transferring said nascent web to said Yankee dryer, adhering said web to said Yankee, and creping said web from said Yankee;recovering a creped, dried bathroom tissue product; andcontrolling the relative amounts of softwood fibers, recycle fibers, hardwood fibers, strength enhancing starch, and cationic nitrogenous softener/debonder in each of said strata wherein said tissue comprising at least two different strata which do not delaminate from each other said strata being selected such that said dried, creped tissue exhibits;a sidedness parameter of less than 0.3, a tensile modulus of no more than 32 grams/percent strain, a GM MMD friction of no more than about 0.225, and a cross directional dry tensile strength of at last 200 grams per 3 inches.