FASHION INDUSTRY DICTIONARY

Define Acid Washing.

Acid washing is a bleeching process that consists of soaking or dampening the pumice with an oxidizing bleach (sodium hypochlorite). The term acid wash is a misnomer because no acid is used. The same process is also called frosting and ice washing. Each new season brings new names to market for the same bleaching process, but with different degrees of intensity.

Cellulase is an enzyme that is sometimes added to pumice stones and/or bleach, or used separately. The cellulase attacks and weakens cellulosic fiber, first on the fiber surface. Because dyes used in denim are mostly on the surface, the effect is a lightening of color, which gives a worn look. Cellulase also destroys fiber fuzz on fabric. Denim is a very strong fabric to begin with, so carefully controlled cellulase treatment has only minimal effect on durability.

Garment finishing for denim and similar apparel has grown over the past decade from a small, almost cottage-industry, to a major industry with exacting test procedures and standards for quality assurance. This work is not performed by traditional textile finishers, but by companies that specialize in this work, most of which were originally industrial laundering facilities.