Water temperature, laundry detergents

An important case is the application of enzymes in laundry detergents. Market trends in the United States show that consumers prefer liquids to powder detergents by a ratio of 2 to 1. These products are stored with no temperature control on shelves in the presence of harsh surfactants, such as linear alkylbenzyl sulfonate (LAS) and require extraordinary measures for stabilization. LAS, by its nature as an effective cleaning agent, causes surfactant-induced unfolding in proteins. There are countless examples of the development of stabilization systems in the intellectual property space. A common theme is to reduce the water activity and to use borate/glycol stabilizers that bind to the active site of proteases. 

Detergents and Wash Temperatures. The purpose of this phase of the study was to determine whether commercially available detergents were as effective in pesticide residue removal when used in washing procedures at "hot," "warm," and "cold" water temperatures. The Important and unique contribution of this study was the close duplication of in-home laundry procedures, with coimnerlcally available detergents and common laundering temperatures. Contaminated swatches were laboratory-laundered in a 60°C (hot) wash/49° C (warm) rinse ... 

A protein can be made that withstands higher temperatures by the introduction of additional disulfide bonds. For example, laundry detergents frequently contain enzymes to remove protein and blood stains. By replacing strategically located amino acid residues with cysteines, a modified enzyme results that stays in its active conformation in hot water. 

The main application of hand dishwashing detergents is to wash dishes by hand. Liquid products can also be used for washing cars, fine laundry, kitchen countertops, and hands. Consumer habits and typical washing procedures vary widely with hand dishwashing. Some of the variables are amount of product used, water temperature, water hardness, use of implements, type of soil, dish surface properties, and time. 

Enzymes are used as ingredients in laundry and dishwashing detergents to improve their efficiency. Their functional efficiency depends on the detergent s components, type of stain to be removed, water temperature, and hardness. Major enzymes used for this purpose are proteases, amylases, lipases, and cellulases. Proteases, which are the most widely used enzymes in the detergent industry, enhance the breakdown... 

Phosphonates are commonly used in laundry powders at 0.5-1.0% of the powder, DTPMP and EDTMP for all uses and HEDP mostly for hardness ion control. Wash conditions for powder detergents are usually pH 9-10 and typical temperatures of 40-60 °C, although there is a strong drive to reduce this to 30 °C or even to use a cold water wash. 

Solid soils are commonly encountered in hard surface cleaning and continue to become more important in home laundry conditions as wash temperatures decrease. The detergency process is complicated in the case of solid oily soils by the nature of the interfacial interactions of the surfactant solution and the solid soil. An initial soil softening or "liquefaction", due to penetration of surfactant and water molecules was proposed, based on gravimetric data (4). In our initial reports of the application of FT-IR to the study of solid soil detergency, we also found evidence of rapid surfactant penetration, which was correlated with successful detergency (5). In this chapter, we examine the detergency performance of several nonionic surfactants as a function of temperature and type of hydrocarbon "model soil". Performance characteristics are related to the interfacial phase behavior of the ternary surfactant -hydrocarbon - water system. 

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