This invention provides a container (10) in the form of a sachet having a body (11) defining a reservoir (12). The body (11) includes a flexible first wall (13) having a line of weakness (14), and a relatively more flexible second wall (15) sealingly joined to the first wall (13), along its periphery. The line of weakness (14) is configured to open up to form an opening in the first wall (13) when the first wall (13) is folded about the line of weakness (14). The invention is characterised in that the line of weakness (14) is bent, resulting in the advantages that the first wall (13) opens in a controlled fashion and the container (10) is able to withstand relatively rough handling and a substantial amount of bending, without the first wall (13) opening accidentally along the line of weakness (14).