Apparatus for impregnating or dispersing a product in a thin substrate

摘要

A method of dispersing a substance in a thin flexible substrate of open-celled foam structure comprising continuously moving a sheet of the substrate, applying the substance to the substrate in a melted condition at an elevated temperature, compressing the substrate, subsequently allowing the substrate to expand to its normal size and thereby draw the melted substance into the open-celled structure to impregnate the substrate and cooling the substrate to solidify the impregnated substance. The method is preferably carried out using apparatus incorporating means for controlling the quantity of substance applied to the substrate by an applicator roller and arranged to permit the substrate to expand while still in contact with the applicator roller.