Problem to be solved: to provide a laminate having high dust collection efficiency and low pressure loss.Solution comprising a fine fiber layer comprising a first fiber and a second principal plane opposite to the first main surface, and a second fiber having an average fiber diameter D2 larger than the average fiber diameter D1 of the first fiber, and a substrate to be laminated on the first principal surface of the ultrafine fiber layer, said fine The number n of the first fibers per unit area in the plane direction of the fiber layer is greater than the number m of the second fibers per unit area in the plane direction of the substrate, and the fine fiber layer is disposed on the second main surfaceProvided with a first region formed by a square having a side A1, sides B1 and C1 perpendicular to the side A1, and a side D1 facing the side A1, and the number NX of the first fiber connecting the side A1 and the side D1 between the side A1 and the side D1 in the first region The laminate is larger than the number ny of the first fiber to connect the side C1.Diagram【課題】高い集塵効率と低い圧力損失とを備える積層体を提供する。【解決手段】第1繊維を含み、第1主面と前記第1主面とは反対側の第2主面とを備える極細繊維層と、前記第1繊維の平均繊維径D1よりも大きい平均繊維径D2を有する第2繊維を含み、前記極細繊維層の第1主面に積層される基材と、を備え、前記極細繊維層の面方向における単位面積あたりの前記第1繊維の本数Nが、前記基材の面方向における単位面積あたりの前記第2繊維の本数Mよりも多く、前記極細繊維層が、前記第2主面に配置され、辺a1と、前記辺a1と直交する辺b1および辺c1と、前記辺a1に対向する辺d1と、を備える正方形により形成される第1領域を備え、前記第1領域内において、前記辺a1と前記辺d1との間をつなぐ前記第1繊維の本数Nxが、前記辺b1と前記辺c1との間をつなぐ前記第1繊維の本数Nyよりも多い、積層体。【選択図】図1
