Abstract: This invention relates to a method of co-dispensing a hair dye composition under pressure wherein there is provided a first container containing a hair dye and propellant material and a second container disposed within the first container containing a hair dye developer material. The second container is provided with a flexible wall against which the propellant acts. A discharge passageway is defined via a nozzle structure and passage of the materials through the nozzle is controlled via a valve structure having first and second valves. The first valve permits control of the flow of material between a first orifice communicating with the first container, a second orifice communicating with the second container and the discharge passageway. The second valve permits control of the flow of material through the second orifice only.

Abstract: This invention relates to a multi-fluid mixing and automatic mettering dispenser for co-dispensing a pressurized permanent hair dye composition, having a first container containing a hair dye and propellant material, a second container disposed within the first container and containing a dye developer material, a nozzle structure defining a discharge passageway and a valve structure having first and second valves for controlling passage of the materials through the nozzle. The nozzle structure permits concurrent operation of the first and second valves to permit simultaneous flow of the materials form the first and second containers through the discharge passageway under the influence of the propellant, such that the materials exit from the dispenser at an overall flow rate not greater than about 1.8 gm/sec, and the flow ratio of the hair dye and propellant material exiting the first valve to the dye developer material exiting the second valve is in the range of about 1.9 to 2.5:1.