Valve for aerosol container

In dispensing a solid in aerosol form it is common to use what is known as a suspension aerosol. This involves the use of a liquid propellant in which a solid to be dispensed is suspended. There is inevitably some difference, however slight, between the respective specific gravities of the propellant and the solid to be dispensed, which means that, with the passage of time and in the absence of other overriding interactions, the two components tend to separate in the container, with a lighter component going to the top or a heavier component going to the bottom over time. Valve for an aerosol container for dispensing a suspension of a substance in a liquid propellant contained therein. The valve comprises a valve body () having at least one orifice () to allow a quantity of the suspension to pass from the container into the valve. The valve further comprises a ring () disposed around the valve body (), the ring being positioned below the at least one orifice to reduce the volume of suspension that can be accommodated within the container below the at least one orifice when the container is orientated with the valve at the bottom, the ring having at least one portion of reduced axial thickness to provide a trough () around the valve body below the at least one orifice.