Esterquats actives

The replacement of DHTDMAC by esterquat in fabric softening compositions represented a turning point. Before then, only two actives accounted for 95% of the cationic softeners in use. Since then, every manufacturer has had its own active ingredient [11,12],... 

Although DHTDMAC fully meets all the needs and expectations criteria listed above, its use has dramatically decreased because of changes in European regulations, which led to its replacement by esterquats in the early 1990s to avoid adverse labeling. Moreover, the formulation of DHTDMAC-based concentrated softeners was not possible without the help of cosofteners. With other actives the technical constraints do not exist or are less stringent. 

FIG. 12.2 Synthesis of softening active molecules (a) DHTDMAC (b) esterquat. 

Other actives (V, VI, VII, and VIII in McConnell [7]) meet European environmental safety regulations (Figure 12.5). They are expected to deliver the same softness as esterquats, but they are more expensive [7], They are used by Unilever and by Kao [7], Puchta also mentions the amide as a valuable alternative to esterquats [8]. 

Esterquats cause fewer problems for formulating ultras and concentrates [7], Carefully selecting structural details of the active such as the mono-, di-, and triester ratio, the presence of unsaturation on the alkyl groups and their cis-trans configuration, the pH value, and the particle size of the dispersion enables one to get stable, low-viscosity softeners containing 20 to 25% active [6], Another advantage of esterquats is that they do not stain fabrics [7],... 

Remarks Esterquat fulfills Actives are Line drying Japan accounts for... 

As a consequence of this specific structure, esterquats upon hydrolysis decompose into non-surface-active fragments. They may be referred to as cleavable surfactants. As a matter of fact, esterquats usually biodegrade more rapidly than the related alkylquats. The hydrolytic instability, on the other hand, comprises a challenge to the user and formulator. While traditional alkylquats are virtually stable under the conditions of use, esterquats... 

By far the largest use of esterquats today is as actives in rinse cycle softener formulations. Softeners at the same time have the largest single use of quaternary ammonium compounds. The breakthrough of esterquats in this application was in 1991, when European detergent manufacturers reformulated their rinse cycle softeners due to pressure from environmental authorities. The active compound under concern, di(hydrogenated-tallow)dimethylammonium chloride (DHTDMAC), which had been used safely for more than 30 years in fabric softeners, was given an environmentally hazardous classification suddenly. The reason was that there was evidence from laboratory studies that the PEC of DHTDMAC may have exceeded its PNEC, particularly in poorly diluted surface waters. 

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