Taber 150E stiffness tester has become a standard tool for stiffness testing, and many notary units directly cite this machine as the standard basis for stiffness specifications.

The unit of stiffness is TSU (Taber Stiffness Unit), and 1 Taber stiffness unit refers to: the test piece with a length of 5cm and a width of 3.8cm is bent to 15° with 1/5 gram of gravity, and 1 stiffness The unit is also equal to 1g.cm. Resilience represents the elastic quality of a material and is the ratio of basic stiffness to initial stiffness. Expressed by the following formula:

Resilience = basic stiffness ÷ initial stiffness x 100

Initial stiffness is the first immediate reading obtained when a sample is bent at a fixed angle and is often used to compare relative stiffness qualities.