Sheet processing apparatus and image forming apparatus

摘要

A sheet processing apparatus and an image forming apparatus are provided which can stabilize the shape of the spine after a squaring process. To square a spine Sb of a sheet bundle S, a spine processing apparatus 400 which squares the spine Sb performs squaring of the spine by moving the spine Sb which projects from a pair of first nipping rollers 405 and 406 while pressing the spine Sb by means of a pressing roller 411 in a state where the spine Sb is nipped by a pair of second nipping rollers 403 and 404.