A hinged cap for a container having a neck, comprising: - a cap body being pivotally mounted between a closed position in which the cap body closes an opening of the neck and an open position in which the cap body is disengaged from the opening of the neck to allow access to the interior of the container; - a tamper-evident ring and - a connecting lug connected on the one hand to the cap body and on the other hand to the tamper-evident ring in such a way that the cap body pivots with respect to the connecting lug about a first pivot axis and the connecting lug pivots with respect to the tamper-evident ring about a second pivot axis parallel to the said first axis; wherein the junction between the connecting lug and the cap body forms a first connection line and the junction between the connecting lug and the tamper-evident ring forms a second connection line; the first connection line being in the form of an arc of a circle oriented towards the tamper-evident ring; the second connection line being in the form of an arc of a circle curved in a direction opposite that of the first connection line; the first and second connection lines being formed by thinned areas having a thickness smaller than the thickness of the cap body and than the thickness of the tamper evident ring so as to be able to fold on themselves and to remain in a folded position beyond a limit folding angle to keep the cap body in a fully open position in which the cap body is completely clear of the neck opening, the tamper-evident ring comprising two arms extending in an angular direction, a central block connecting the arms to each other, and a recess separating the arms and the central block from the remainder of the tamper-evident ring; the connecting tab being connected to the central block of the tamper-evident ring; the cap being characterised in that: - the central block comprises an upper end portion having a bevelled outer face in the radially inward direction of the cap; - the bevelled outer face forms a bearing seat for the connecting tab when the cap body is in a fully open position. - a cap body being pivotally mounted between a closed position in which the cap body closes an opening of the neck and an open position in which the cap body is disengaged from the opening of the neck to allow access to the interior of the container; - a tamper-evident ring and - a connecting lug connected on the one hand to the cap body and on the other hand to the tamper-evident ring in such a way that the cap body pivots with respect to the connecting lug about a first pivot axis and the connecting lug pivots with respect to the tamper-evident ring about a second pivot axis parallel to the said first axis; wherein the junction between the connecting lug and the cap body forms a first connection line and the junction between the connecting lug and the tamper-evident ring forms a second connection line; the first connection line being in the form of an arc of a circle oriented towards the tamper-evident ring; the second connection line being in the form of an arc of a circle curved in a direction opposite that of the first connection line; the first and second connection lines being formed by thinned areas having a thickness smaller than the thickness of the cap body and than the thickness of the tamper evident ring so as to be able to fold on themselves and to remain in a folded position beyond a limit folding angle to keep the cap body in a fully open position in which the cap body is completely clear of the neck opening, the tamper-evident ring comprising two arms extending in an angular direction, a central block connecting the arms to each other, and a recess separating the arms and the central block from the remainder of the tamper-evident ring; the connecting tab being connected to the central block of the tamper-evident ring; the cap being characterised in that: - the central block comprises an upper end portion having a bevelled outer face in the radially inward direction of the cap; - the bevelled outer face forms a bearing seat for the connecting tab when the cap body is in a fully open position. - the central block comprises an upper end portion having a bevelled outer face in the radially inward direction of the cap; - the bevelled outer face forms a bearing seat for the connecting tab when the cap body is in a fully open position.