However, further solvent changes and reductions or even eliminating the use of solvents is a continuing challenge to process chemists and engineers. Waste reduction is also a continuing challenge. Toxic reagents and reactants, as well as the waste that they generate, are being more effectively handled or eliminated altogether. The use of a potentially hazardous chemical intermediate is sometimes difficult to avoid without drastically changing the traditional cost of a material. By carrying out the Diels-Alder reaction of myrcenol and acrolein at a manufacturing site where the latter material is produced, transport and use of acrolein in aroma chemical plants can be avoided.
Related regulations are in place in other parts of the world.
These all affect manufacturing practice. The demands of customers for ever-improving fragrance performance has been a key driving force for fragrance research over the past several decades. However, the technical demands for performance are very much a function of the nature of the specific application. Here are some important applications, roughly in order of increasing technical demand. Category Products Personal grooming Perfumes, colognes Personal care Soaps, shampoos, cosmetics Laundry care Powder and liquid detergents, fabric softeners Household care Bleaches, hard-surface cleaners, toilet cleaners Some of the key attributes that can be used to evaluate performance of an aroma chemical or a fragrance are shown in the sidebar entitled Performance attributes .