properties of paper towels::Cd refers to cross direction, and md to machine direction, droop rigidity is higher in the machine direction properties of paper towels

properties of paper towels::Cd refers to cross direction, and md to machine direction, droop rigidity is higher in the machine direction.
The higher the value the stiffer the paper.
Droop rigidity md : droop rigidity measures the stiffness of the paper or board, more often applied to lighter weight grades.
Cd refers to cross direction, and md to machine direction, droop rigidity is higher in the machine direction.
The higher the value the stiffer the paper.
The standards are as per tappi t 556.