Bending Moment Characteristics on Repeated Folding Motion of Coated Paperboard Scored by Round-Edge Knife

抄録

This work deals the creasing characteristics of coated paperboard. It was not clarified to estimate the deformation behavior of creased line from the first peak bending moment M_p1 and the initial gradient C₁ of bending moment. In this study, a new prototype testing apparatus has been developed for seeking the bending moment and the side view picture of creased part during repeated folding motion. The permanent (residual) deformation angles, the variance of residual stiffness and the hysteresis characteristics of bending moment were analyzed for the nominal shear strain (the scoring depth) γ . The obtained results were as follows: (1) C₁ was characterized with γ, while the second term gradient C₂ was characterized with γ and the inverse of tracking angle Θ^-1. (2) By introducing the area of closed curve of second term hysteresis A_CC, it is revealed that the gradient of A_CC was remarkably varied with Θ at near the peak point M_p1.