On a portion of the circumferential surface of a first roll (5) in the circumferential direction (R), a protrusion group (4P), in which multiple protrusions (4) are disposed in a regular pattern, is formed. For the foremost protrusions (4Q) of the multiple protrusions (4) configuring the protrusion group (4P), the foremost protrusions being located in the foremost section of the first roll (5) in the rotation direction (R1) and being the first to contact a composite sheet (10A), the front edges (41) of the tops (40) of the foremost protrusions in the rotation direction (R1) are straight lines (30) that are parallel to the rotational axis direction (A) of the first roll (5). For the other protrusions (4) other than the foremost protrusions (4Q) in the protrusion group (4P), the front edges (41) of the tops (40) of the protrusions in the rotation direction (R1) are corners (31) configured by two sides (42, 43) that intersect with each other and the two sides (42, 43) all intersect with both the rotational axis direction (A) and the circumferential direction (R).於第1輥(5)之周面之周向(R)之一部分,形成有複數個凸部(4)以規則之圖案配置而成之凸部群(4P)。構成凸部群(4P)之複數個凸部(4)中之位於第1輥(5)之旋轉方向(R1)之最前部而最先與複合片材(10A)接觸之最前部凸部(4Q)之頂部(40)之旋轉方向(R1)之前端(41)為與第1輥(5)之旋轉軸方向(A)平行之直線(30)。凸部群(4P)中之最前部凸部(4Q)以外之其他凸部(4)之頂部(40)之旋轉方向(R1)之前端(41)為由相互交叉之兩邊(42、43)所構成之角部(31),該兩邊(42、43)均與旋轉軸方向(A)及周向(R)兩方向交叉。4‧‧‧凸部4P‧‧‧凸部群4Q‧‧‧最前部凸部4R‧‧‧最後部凸部4X‧‧‧凸部行4Y‧‧‧凸部行30‧‧‧直線31‧‧‧角部40‧‧‧頂部40s‧‧‧側面41‧‧‧前端42‧‧‧邊43‧‧‧邊44‧‧‧後端A‧‧‧旋轉軸方向R‧‧‧周向R1‧‧‧方向W1‧‧‧間隔W2‧‧‧間隔X‧‧‧方向Y‧‧‧方向θ‧‧‧角度
