This invention relates to a poly photographic multilayer film base having improved properties with regard to cutting, stiffness and curl property. , and maintains the antifouling effect despite surface wear occasioned by long-term use in industrial processes involving nonwoven fabric. In addition, each memory cell transistor may includes a floating gate between a control gate electrode and a semiconductor substrate, and sourcedrain regions of the semiconductor substrate may be included on opposite sides of the control gate electrode. The porous body is disposed in the exhaust passage. The milling head is preferably attached to a rotary milling tool, i.