Another one of usages of aluminum sulfate is in dyeing and printing on cloth. When dissolved in a large amount of water that has a neutral or slightly alkaline pH, the compound produces a gooey substance, aluminum hydroxide. The gooey substance helps dyes stick to the cloth fibers by making the dye water insoluble. The role of aluminum sulfate, then, is as a dye “fixer,” which means that it combines with the molecular structure of the dye and the fabric so the dye doesn’t run out when the fabric gets wet.