6 N-Acyl ED3A Chelating Surfactants: Properties and Applications in ...

Alkyl Polyglycosides 33
ing detergents (premium products) which are essentially based on two surfactant
systems: LAS/FAES/fatty-acid alkanolamide and FAES/betaine/amine oxide.
The inexpensive private label products (economy brands) have distinctly lower
active substance contents and, accordingly, are of significantly lower performance
for the same dosage. Nearly crystal-clear manual dishwashing detergents
with excellent skin compatibility were introduced onto the market in 1992. They
are based on FAEO and betaine and contain relatively small quantities of anionic
surfactants, for example FAES. In 1995, various manufacturers began marketing
manual dishwashing detergents which can also be used as a liquid hand soap and
which contain an antibacterial agent. In North America, too, the advantages of
alkyl polyglycosides (performance, foaming behavior, and skin compatibility)
have already resulted in the reformulation of more than 10 brands.
Conventional manual dishwashing detergents. The majority of conventional
dishwashing detergents are based on LAS due to the relatively high cost of
FAES as compared with LAS. As in Europe, alkyl polyglycosides are used as cosurfactants
in these products. The optimum cost/effectiveness ratio of LAS/alkyl
polyglycoside surfactant combinations under American conditions is between
3:1 and 4:1. Formulations and selected performance figures both for LAS- and
FAES-based products are shown in Figure 27. The performance of both the
LAS- and the FAES-based premium product is comparable with that of the market
leader in the premium segment. Various manufacturers have meanwhile introduced
such alkyl polyglycoside containing products onto the market.
Concentrated manual dishwashing detergents. Concentrated manual dishwashing
detergents known as ultraliquids were brought onto the market in 1995
by various manufacturers. These products are marketed in 14.7-oz bottles in contrast
to the conventional 22-oz bottles. The recommended dosage is one-third
lower than that of conventional products for the same performance. Ultra liquids
contain around 45% to 50% surfactants as compared to about 30% in conventional
dishwashing detergents. Accordingly, the use of alkyl polyglycosides is an
advantage in ultraliquids because, by virtue of the interactions with anionic surfactants
described earlier, highly effective products with relatively low active
substance contents can be formulated with alkyl polyglycosides. In addition,
alkyl polyglycoside containing ultra liquids require less hydrotrope than
non–alkyl polyglucoside ultraliquids. As in the case of conventional dishwashing
detergents, the partial or complete replacement of FAES by alkyl polyglycosides
leads to increases in performance. Table 6 contains examples of alkyl
polyglycoside containing ultra liquids which are comparable in cost and performance
with leading ultra liquids of the North American market.
I&I solid blocks. In addition to liquid manual dishwashing detergents, socalled
solid blocks are also available on the American I&I market. Doses of
these products are dispensed by means of a jet of water which dissolves out part