Patent ID: 6328849
Filing Date: 2001-12-11
Classification: B31F,D21F,D21H,Y10S,Y10T

Abstract:
A process for the manufacture of a soft, single-ply tissue product having a basis weight of at least about 15 lbs./3,000 square foot ream and having low sidedness which process comprises:providing a moving foraminous support;providing a headbox adjacent said moving foraminous support adapted to form a nascent web by depositing furnish upon said moving foraminous support;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 wet pressing means and adopted to receive and dry the dewatered nascent web;supplying a furnish to said headbox comprising cellulosic papermaking fiber chosen from the group consisting hardwood, softwood, and recycled fibers, and cationic aldehyde-containing cationic temporary wet strength agents and cationic nitrogenous softener/debonder;controlling the overall concentration of the aldehyde-containing cationic temporary wet strength agent and the cationic nitrogenous softener/debonder in said nascent web to between about 1 to about 20 lbs./ton on a dry fiber basis, the weight ratio of the wet strength agent to the softener debonder being controlled to be within the range of about 0.5 to about 10.0;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; andforming a roll of a single-ply tissue;controlling the relative amounts of the temporary wet strength agent and the nitrogenous softener/debonder such that said dried tissue exhibits:a specific total tensile strength of between 40 and 75 grams per 3 inches per pound per 3000 square feet ream, a cross direction specific wet tensile strength of between 2.75 and 7.5 grams per 3 inches per pound per 3000 square feet ream, the ratio of MD tensile to CD tensile of between 1.25 and 2.75, a specific geometric mean tensile stiffness of between 0.5 and 1.2 grams per inch per percent strain per pound per 3000 square feet ream, a friction deviation of less than 0.225, and a sidedness parameter of less than 0.275.