Insufficient tensile strength in toilet paper produced by papermaking machinery can be categorized into longitudinal and transverse tensile strength, which is related to pulp speed, fiber orientation, the process ratio of the toilet paper machine, and fiber bonding strength.
1. The pulp speed ratio of a toilet paper machine is the ratio of the wire cage speed to the pulp pump speed. A higher ratio results in greater longitudinal tensile strength and less transverse tensile strength; conversely, a lower ratio results in greater transverse tensile strength and less longitudinal tensile strength. However, it cannot exceed a certain range, otherwise, the opposite effect will occur.
2. Fiber orientation is the standard for determining longitudinal and transverse tensile strength. Controlling the fiber orientation can be achieved by adjusting the opening of the headbox return valve on the toilet paper machine. A larger opening results in greater transverse tensile strength, while a smaller opening results in greater longitudinal tensile strength.
3. The bonding strength of the fibers themselves: Factors affecting fiber bonding strength include the influence of hemicellulose, cellulose, and lignin; the fiber length itself; the use of chemical additives and auxiliaries; the linear pressure of the press section; the drying temperature; the bonding strength between fibers; the strength of the fibers themselves; and the distribution and orientation of fibers in the wet paper sheet.
