Existing folding litter trays require a manual material manipulation that is difficult to undertake and may require additional supplies in order to ensure the rigidity of the tray. Not carrying out these operations properly may reduce the fluidtightness and stability of the tray, impairing its hygienic efficiency and making it unfit for purpose. The box (1) according to the invention is made up of a laminated multilayer complex (15) with aesthetic, biodegradable, recyclable, fluidtight, non-soiling and deodorizing properties. The inventiion eliminates the problem of making-up by giving the sidewalls of the box (1) a preloaded bowed shape-memory spring effect (17) ensuring that they are rigid in the open position thus ensuriing the functionality of the box (1) with no prior manipulation. The invention can be used as a travel or day-to-day solution. It can be combined with litter to form a ready-to-use entity.
