In the previous paper, the apparatus developed in our laboratory for measuring liveliness of paper was described. It was shown that under the standard condition the liveliness haa a good correlation with the bending stiffness EI (E : Young's modulus, I : moment of inertia).
This paper discusses the relationship between the liveliness and the calculated EI for the commercial xerography papers. Below 65% of relative humidity, the response of paper to strain is similar to that of elastic body. The liveliness of paper decreases with the increase in the moisture content and is proportional to the calculated EI and Gurley's rigidity.
On the other hand, in the range of higher relative humidity, bending causes permanent deformation in the sheet structure, and the deformation depends on the bending time during the measurement of the liveliness. These findings reveal that the repeated measurement of livelinessis more suitable than the conventional bending tester for evaluation of the practical bending property, which is closely related to feeding properties of xerography paper under the circumstances of high humidities.