Laundry detergent is a type of detergent (cleaning agent) used for cleaning dirty laundry (clothes). Laundry detergent is manufactured in powder (washing powder) and liquid form. While powdered and liquid detergents hold roughly equal share of the worldwide laundry detergent market in terms of value, powdered detergents are sold twice as much compared to liquids in terms of volume. History From ancient times, chemical additives were used to facilitate the mechanical washing of textile fibers with water. The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BC in ancient Babylon. German chemical companies developed an alkyl sulfate surfactant in 1917, in response to shortages of soap ingredients during the Allied Blockade of Germany during World War I. In the 1930s, commercially viable routes to fatty alcohols were developed, and these new materials were converted to their sulfate esters, key ingredients in the commercially important German brand FEWA, produced by BASF, and Dreft, the U.S. brand produced by Procter & Gamble. Such detergents were mainly used in industry until after World War II. By then, new developments and the later conversion of aviation fuel plants to produce tetrapropylene, used in household detergents production, caused a fast growth of domestic use in the late 1940s. Soils Washing laundry involves removing mixed soils from fiber surfaces. From a chemical viewpoint, soils can be grouped into: Water-soluble soils such as sugars, inorganic salts, urea, and perspiration. Solid particulate soils such as rust, metal oxides, soot (carbon black), carbonates, silicates, and humus. Hydrophobic soils such as animal fats, vegetable oils, sebum, mineral oil, and grease. Proteins such as blood, egg, milk, and keratin from skin. These require enzymes, heat or alkali to hydrolyze and denature them into smaller parts before they can be removed by the surfactants. Bleachable stains such as wine, coffee, tea, fruit juices, and vegetable stains. Bleaching is an oxidation reaction which turns the colored substance into a colorless one, which either stays on the fabric or may be easier to wash out. Soils difficult to remove are pigments and dyes, fats, resins, tar, waxes, and denatured protein. Components Laundry detergents may contain builders (50% by weight, approximately), surfactants (15%), bleach (7%), enzymes (2%), soil antideposition agents, foam regulators, corrosion inhibitors, optical brighteners, dye transfer inhibitors, fragrances, dyes, fillers and formulation aids. Builders Builders (also called chelating or sequestering agents) are water softeners. Most domestic water