The elasticity and plasticity of paper

During various processes such as storage and printing, paper will undergo various changes due to the differences in the surrounding environment. If subjected to external force, the paper will instantly change its shape and size, and when the external force stops, it will return to its original shape and size. This deformation process is called sensitive elastic deformation. When paper is subjected to external force, it changes its shape and size within a certain interval. When the external force stops acting, it gradually returns to its original shape and size. This deformation process is called hysteretic deformation. When the external force is removed but the paper remains in the state of shape and size deformation caused by the external force, it is called plastic deformation. Sensitive elastic deformation and hysteroelastic deformation are reversible deformations, while plastic deformation is irreversible.