Spiral membrane element and end member for spiral membrane element

A spiral membrane element comprising:

• an element body including a central tube, and a membrane leaf having a separation membrane and wound around the central tube;
• an end member provided at one or both ends in an axial direction of the element body;
• and
• an exterior material covering at least an outer circumferential surface of the element body, wherein
• the end member includes a body portion of which a cross-section perpendicular to the axial direction has a circular outline, and an annular skirt portion,
• the body portion has a first protrusion formed in a circumferential direction,
• the skirt portion extends toward the element body side from the first protrusion and is located between the element body and the exterior material, and
• the end member satisfies at least one selected from the group consisting of the following requirements (1) to (3):
• (1) the first protrusion has a cut-in portion formed in an edge portion thereof on the skirt portion side, and a part of the exterior material is placed into at least a part of the cut-in portion;
• (2) the skirt portion has at least one of a hole and a through hole formed in an outer circumferential surface thereof, and a part of the exterior material is placed into at least a part of at least one of the hole and the through hole;
• and
• (3) the first protrusion has a recess formed in a direction tilted relative to the axial direction in an end surface thereof on the skirt portion side, and a part of the exterior material is placed into at least a part of the recess.