A closure assembly comprising: - an article that is injection moulded of plastic material and forms a tubular neck around a product passage in said article, said neck having a main axis and forming a mouth at a top end of said product passage, said neck having an exterior side; - a rotational cap that is injection moulded of plastic material and that is secured on or is to be secured on said neck of the article, the cap sealing the product passage in closed position of the cap on said neck, and the cap - for removal of the cap from the neck of the article by a user to open the product passage - being adapted to be manually rotated from the closed position in an opening direction; wherein the cap comprises a top wall and a downward depending skirt, said skirt having an interior side, an exterior side, and a lower edge remote from the top wall, wherein the exterior side of the neck and the interior side of the skirt have cooperating first and second screw threads (9,23) on said neck and skirt respectively, wherein the cap furthermore comprises a tamper-evident ring that is integrally moulded to the skirt, said tamper-evident ring being composed of at least two ring segments, each ring segment having a base portion and an indicator portion, wherein the base portion is connected via one or more non-frangible connector portions to the skirt, said base portion extending from a trailing end thereof in opening direction over a base portion angle about the main axis, said base portion having an inner face with an inner face radius about the main axis, and wherein the indicator portion is integral with the base portion at a junction and extends from the junction in opening direction over an indicator portion angle about the main axis to a head end of the indicator portion, wherein the indicator portion is connected at the head end thereof via an integrally moulded frangible bridge to an adjacent trailing end of a base portion of another ring segment, wherein the article has for each ring segment of the tamper-evident ring a rotation preventing boss, said boss being arranged to be engaged by a corresponding head end of an indicator portion of the segment, wherein the cap with tamper-evident ring is embodied such that upon rotating the cap in opening direction by the user from its closed position for the first time, the head end of the indicator portion engages the boss which then prevents the head end from further motion in opening direction of the cap, the frangible bridge between said head end and the trailing end of the base portion breaking, and the indicator portion being subjected to permanent deformation, characterized in that the boss has a catch portion having a recess at a side of the boss facing the head end of the indicator portion and having an catch portion outer wall with an outer face that is arranged along the inner face of the base portion near the trailing end thereof when said cap is in its closed position, and in that the head end of the indicator portion is arranged at a spacing radially inward from the trailing end of the adjacent base portion when said cap is in its closed position, such that - upon rotating the cap in opening direction by the user from its closed position for the first time - the head end of the indicator portion enters the recess of the catch portion and is then prevented from further motion in opening direction of the cap, whilst the catch portion outer wall comes in the spacing between the spaced apart head end and trailing end, the frangible bridge between said head end and trailing end breaking and the indicator portion bending, folding, and/or buckling whilst being subjected to permanent deformation upon further rotation of the cap in opening direction. - an article that is injection moulded of plastic material and forms a tubular neck around a product passage in said article, said neck having a main axis and forming a mouth at a top end of said product passage, said neck having an exterior side; - a rotational cap that is injection moulded of plastic material and that is secured on or is to be secured on said neck of the article, the cap sealing the product passage in closed position of the cap on said neck, and the cap - for removal of the cap from the neck of the article by a user to open the product passage - being adapted to be manually rotated from the closed position in an opening direction;