A seal intended to ensure a sealing between a rotary shaft and a stationary body of a machine, comprising: - a friction ring having an axis of symmetry X and two surfaces (120, 122) extending radially with relative to the axis X, - a counter-ring having an axis of symmetry coincident with the axis X and a radial friction surface bearing against one of the radial surfaces of the friction ring, - a compression spring bearing against a transmission element having an axis of symmetry coincident with the axis X, the transmission element having a cylindrical wall including a first end forming a first radial flange located on the side of the counter-ring and extending in a direction opposite to the axis X and a second opposite end forming a second radial flange extending in the direction of the axis X, the friction ring having a cylindrical outer surface of axis X connecting, in particular directly, the two radial surfaces (120, 122) thereof, and the compression spring bearing against the first flange of the transmission element, the second flange of the transmission element being located partially facing the radial surface of the friction ring which is remote from the counter-ring and the cylindrical wall of the transmission element being located partially facing the cylindrical outer surface of the friction ring, and the seal further comprising: a bearing ring of the compression spring, this bearing ring having a cylindrical portion of axis X located at least partially facing the cylindrical portion of the transmission element and a radial portion extending in the direction of the axis X, facing the first flange of the transmission element, said seal being characterised in that a secondary sealing element extends partially between the transmission element and the friction ring and partially between the bearing ring and a casing housing the friction ring, the transmission element, the compression spring and the secondary sealing element. - a friction ring having an axis of symmetry X and two surfaces (120, 122) extending radially with relative to the axis X, - a counter-ring having an axis of symmetry coincident with the axis X and a radial friction surface bearing against one of the radial surfaces of the friction ring, - a compression spring bearing against a transmission element having an axis of symmetry coincident with the axis X, the transmission element having a cylindrical wall including a first end forming a first radial flange located on the side of the counter-ring and extending in a direction opposite to the axis X and a second opposite end forming a second radial flange extending in the direction of the axis X, the friction ring having a cylindrical outer surface of axis X connecting, in particular directly, the two radial surfaces (120, 122) thereof, and the compression spring bearing against the first flange of the transmission element, the second flange of the transmission element being located partially facing the radial surface of the friction ring which is remote from the counter-ring and the cylindrical wall of the transmission element being located partially facing the cylindrical outer surface of the friction ring, and the seal further comprising: a bearing ring of the compression spring, this bearing ring having a cylindrical portion of axis X located at least partially facing the cylindrical portion of the transmission element and a radial portion extending in the direction of the axis X, facing the first flange of the transmission element, said seal being characterised in that a secondary sealing element extends partially between the transmission element and the friction ring and partially between the bearing ring and a casing housing the friction ring, the transmission element, the compression spring and the secondary sealing element. a bearing ring of the compression spring, this bearing ring having a cylindrical portion of axis X located at least partially facing the cylindrical portion of the transmission element and a radial portion extending in the direction of the axis X, facing the first flange of the transmission element, said seal being characterised in that a secondary sealing element extends partially between the transmission element and the friction ring and partially between the bearing ring and a casing housing the friction ring, the transmission element, the compression spring and the secondary sealing element.