Abstract: An apparatus for dyeing a cellulosic textile substrate with reduced indigo dye in a leuco-state in an inert atmosphere substantially isolated from oxidizing substances. A plurality of applicator faces that each apply a portion of the total dye application. The first foam applicator is spaced from the entrance of the chamber to allow air entrapped in the interstices of the substrate to escape. The applicators are spaced from each other to allow collapse of the foam and dispersion of the dye applied in the previous applicator before the substrate reaches the next applicator. Similarly, the exit is spaced from the last applicator to allow the foam to collapse and the dye to disperse prior to exiting the apparatus and entering the atmosphere in which oxidization of the dye occurs.

Abstract: Dyeing a cellulosic textile substrate with reduced indigo dye in a leuco state after foaming with an inert gas to maintain the dye isolated from oxidizing substances. Following application of the foam to the substrate, it is exposed to the adjacent atmosphere, with the oxygen in the atmosphere oxidizing the reduced indigo dye to regenerate it and cause it to affix to the textile substrate. A product can be produced using the method and apparatus of the present invention that has different dye characteristics on opposite surfaces of the substrate by applying the indigo dye foam to one surface and another dye, either an indigo dye or some other dye to the opposite surface.