Patent ID: 7341579

Claim:
A sanitary napkin comprising: an elongated main body having a liquid absorbent layer for absorbing and retaining liquid, the elongated main body being symmetrically disposed about a longitudinal centerline extending in an elongated direction of the elongated main body; and rear flaps located in proximity to a rear edge of the sanitary napkin, and projecting laterally in opposite directions from laterally opposing side edges of the liquid absorbent layer, the sanitary napkin being adapted to be worn with the rear flaps kept in an unfolded state on an inner side of an undergarment, each rear flap including a first sheet which is corrugated such that each rear flap has adjacent corrugated regions and at least one strip-shaped or linear smooth region extending continuously over a substantially entire length of each rear flap between the adjacent corrugated regions and in a direction that is substantially parallel to said longitudinal centerline, each corrugated region having hills and valleys which extend laterally and alternate with each other in a direction that is substantially parallel to said longitudinal centerline, the smooth region being free of the hills and valleys or having a smaller difference in level between hills and valleys than the corrugated region.