CORE FOR CORRUGATED PAPER MATERIAL AND CORRUGATED PAPER SHEET, AND STEPPED ROLL FOR PRODUCING CORE FOR CORRUGATED PAPER MATERIAL, DEVICE FOR PRODUCING CORE FOR CORRUGATED PAPER MATERIAL, DEVICE FOR PRODUCING CORRUGATED PAPER SHEET AND METHOD OF PRODUCING CORE FOR CORRUGATED PAPER MATERIAL

摘要

The invention relates to a core for corrugated paper material and a corrugated paper sheet, and a stepped roll for producing core for corrugated paper material, a device for producing core for corrugated paper, a device for producing corrugated paper sheet and a method of producing core for corrugated paper material. A core is produced by using stepped roll (104, 104a, 104b) in which a ridge and a root in a wavy peripheral surface (124) are each formed by a single arc and there is a predetermined difference between the radius (A1) of the ridge and the radius (A2) of the root.