Minor Ingredients and Aesthetics

After anionics, nonionics are the next biggest category of surfactant in APCs. These are used to a very limited extent in powder cleaning formulas. However, they are used in cream cleansers, which tend to be more complex formulations. Nonionics are extensively used now in liquid APCs and floor cleaners and the spray cleaners. There are even some few cases reported of APCs formulated entirely from nonionics, with no anionics at all [78,79]. Nonionics are well known for then-ability to adsorb to greasy/oily surfaces, although they tend not to emulsify the oils in solution as well as the anionics. The properties of the two classes of surfactants would seem therefore to be complementary, and many modem formulation patents and publications describe these types of combinations [80-82]. 

FIGURE 2.3 Structures of common disinfectant quats. la, the benzyl quat, is most commonly found in commercial products. Usually a combination of alkyl chain lengths are used in one product. 

One of the most important effects of surfactant synergy in liquid hard-surface cleaners is that the overall concentration of active ingredients can be reduced. More importantly, the amount of adjunct materials—builders, solvents, and the like—that must be added are decreased as the surfactant efficiency and effectiveness is increased due to synergy. While this has the effect of increasing 

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