an improved triple wall corrugated paper board fold construction is formed by joining a single face web with a nonadhered band of the medium to a contiguous liner of another one of the single face webs , slitting and removing a portion of the nonadhered band along a narrow bending area , and removing the slit strip to leave a bending groove formed with one or more score lines in the material underlying the groove , as the board continuously moves along a path of travel .