A production apparatus (20) is equipped with a slit-forming roller (21), a transfer roller (22), and an anvil roller (23) which is positioned facing both the slit-forming roller and the transfer roller. A cover sheet web (W8) is conveyed so as to pass through a slit-forming position (PS) between the slit-forming roller (21) and the anvil roller (23), and then pass through a transfer position (PT) between the transfer roller (22) and the anvil roller (23). The slit-forming roller (21) intermittently forms a plurality of slits in the direction of conveyance in the cover sheet web (W8) at the slit-forming position (PS). The transfer roller (22) intermittently transfers release sheet pieces (12), so as to span the slits, onto the cover sheet web (W8) at the transfer position (PT).
