Detergency performance

J. Parker and O. Raney, "The Use of Peroxygen Compounds as a Means of Improving Detergent Performance," in C. Bapa, ed., Hew Hori ns 19S9A.nA.OCS CSMA Tdetergent Industry Conference Hershey, Pa., 1989. 

If one compares several commercial LAS samples for foam stability, detergency performance, critical micelle concentration (CMC), hardness sensitivity, or... 

The DATs present in LAB will readily sulfonate to form dialkyltetralin-sulfonate or DATS. The foam and detergency performance properties of individual C DATS homologs are very similar to that of the corresponding C j LAS homologs [21]. Thus, even at a level of 10% DATS in the LAB, no decrease in foam or detergency performance is observed. In some liquid formulations, the presence of DATS can provide a beneficial hydrotropic effect to LAS [22]. Figure 8 illustrates that DATS are indeed surfactants, as evidenced by their surface tension vs. concentration plot. 

Improved detergency performance at low-use or underbuilt washing conditions... 

The net result is that detergency performance for mixed active formulations is not so drastically reduced by high water hardness conditions. The improvement in detergency by mixed surfactant systems can be seen not only in under-... 

It has been reported that the LAS/AS mixed active system was produced by continuous oleum sulfonation of LAB followed by addition of the alcohol and more oleum to provide a tandem sulfation [40]. Tallow range alcohol sulfate (Ci6-is AS) was used in the past when U.S. wash temperatures were as high as 60°C. At these wash temperatures and in phosphate-built formulations the Ci6 18 AS gave very good detergency performance [41]. However, as U.S. washing temperatures decreased, C16.,8 AS was replaced by the more soluble shorter-chain ASs, such as C12.I8 or C,4, 5. 

Studies on the detergency performance and cost optimization of the LAS/AS/ AES have been published [42,43]. Figure 19 shows the performance optimization on sebum soil on cotton cloth and a cotton/polyester permanent press cloth. 

In addition to detergency performance and feedstock economics, other factors related to the processing of these powder formulations must be considered, such as sulfonation/sulfation, crutcher slurry preparation, and spray drying. AS and AES are thermally and hydrolytically less stable than LAS. Care must be taken in spray drying to avoid decomposition and pluming problems. This may place a limitation on the levels of AS and AES in spray-dried laundry powders. 

FIG. 19 Detergency performance of LAS/AES/AS mixtures with phosphate and carbonate builders. Shaded zones represent optimum detergency performance. Conditions 38°C, 0.15 concentration, 15% surfactant/30% builder, 50 and 150 ppm hardness, sebum soil. (From Ref. 42.)... 

It has been reported that LAS/AOS combinations exhibit favorable synergy in detergency performance and a reduced sensitivity to water hardness [49]. 

Because of its superior solubility characteristics, a high 2-phenyl LAS (with an alkyl chain length average of 11.4) was the preferred type. The detergency performance of one LAS/AE type of formulation was discussed previously (see Figs. 12 and 13). Early commercial heavy-duty liquid (HDL) formulations were built with phosphate, but since 1979 almost all U.S. HDLs have been formulated without phosphate. 

The tolerance toward calcium of mixtures of commercial C10-C14 LAS and commercial C16-C18 AOS has been studied by Suri et al. [3]. Their results in Fig. 6 show too that AOS has superior tolerance toward calcium as compared with LAS. Partial substitution of LAS by AOS improves the hardness sensitivity of LAS. This in turn will improve the detergency performance of such mixtures in hard water. 

The types of analyses discussed in this section can be divided into two groups active matter and impurities. Several methods assess the anionic surfactant (active matter) content of the AOS product. These are particularly important since detergent performance is directly related to surfactant concentration. The different types of anionic active material are identified and quantified. 

Formulations based on soap and an amphoteric LSDA were superior in performance to those containing soap and anionic LSDA [29]. Whereas soap-anionic LSDA formulations could not tolerate the addition of sodium sulfate, a commonly used detergent diluent, the analogous amphoteric LSDA formulations tolerated addition of up to 20% Na2S04 quite well. Detergency performance of such formulations was equal or superior to that of a high-phosphate control. 

Okumura [49] in his report A Super Concentrated Heavy Duty Powder Detergent Containing Palm-MES, Production and Performance cites the annual production of MES to be approximately 70,000 tons. New formulations of MES have been successfully introduced in the heavy-duty detergent market, showing excellent detergency performance under normal Japanese washing condi-... 

Oleochemical-based alcohols are generally produced from either coconut or palm kernel oils. These lauric oils have carbon chain distributions in the C12-C14 range, where detergency performance is optimum. Figure 1 summarizes the... 

Another way to achieve high detergency performance while keeping environmental impacts low is by making intelligent products with built-in sensor functions. In these applications, the products can respond to external stimuli and fulfil their task. The inherent sensoric principles of two recent innovations, detergent tablets and dishwashing tablets with built-in rinse aid, will be discussed. 

Comparison of Detergency Performance with Experimental and Thermodynamic Wetting Theories... 

Acyl chain length, effect on binary phase diagram of G type nonionics, 42 Adhesion, LAS detergency performance, 250f Adsorption... 

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