Detergent Tablets

Uses Antimicrobial, hard surf, disinfectant, sanitizer, fungicide for hospitals, public institutions, powd. and tableted detergent disinfectants, fabric softener sanitizers algicide in swimming pool and industrial water treatment deodorizer indirect food additive in sanitizing sol ns. for food contact surfs., equip. antimicrobial in pharmaceuticals... 

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. 

Tablets are the most compact form of non-liquid detergents. Their density ranges from 1.0 to 1.3kg/L, providing further benefits such as lower packaging...

The main difference in composition between heavy-duty detergent tablets and other supercompact detergents lies in the use of disintegrants. 

This technology can also be applied for pre-dosed detergents like tablets [79], which offer the advantage of an easier determination of detergent already fed into the washing tub. 

Heavy-duty detergent tablets for textile laundry, as mentioned in chapter 4.2.4, use the presence of water to activate a sophisticated disintegration system that dispenses the tablets in a few seconds even though these products have to be stable and hard during storage and application [90, 91, 92]. These two systems are discussed in more detail in the following sections. 

Effervescence these systems that consist for instance of a carbonate or bicarbonate salt and an organic acid like e.g. citric acid, develop carbon dioxide gas on contact with water and are well known in pharmaceutical/health food tablets. A few market products exist that make use of this system but for reasons explained above this system is not that suitable for detergent tablets with a high content of surfactants. 

Highly water-soluble substances like e.g. Na (K) acetate or Na (K) citrate that are mixed to the active substances of the tablet. They enable the water to penetrate immediately and weaken the binding forces inside the tablet. These systems are sometimes used in detergent tablets. 

Granular swelling agents. These systems typically consist of cross-linked hydrophilic polymers like e.g. cross-linked poly-(N-vinyl pyrrolidone) or hydrophilic but insoluble polymers, e.g. cellulose that swell to a considerable volume within a few seconds on contact with water. These systems are powerful disintegrants and are used particularly in quick-release detergent tablets put in a dispenser tray. 

The development of these systems in the late 1990s enabled the detergent tablet to gain a notable market share and to facilitate the housewife s work, offering her a high-performing, convenient product. 

Some quality factors, especially secondary ones, depend directly on material or structural attributes of the product. These product quality factors are often arbitrary and can only be qualitatively evaluated by panels of consumers or experts. Convenience for use, product stability, and ability for human skin protection are all examples of these quality factors. Each arbitrary performance index has specific relationships with the material/structural attributes. In such cases, the desirable quality factor can be realized by directly changing the formulation without concerning any of the performance indices. An example can be that to make a laundry detergent product more convenient to use, the product form can be changed from powder to tablet. Another example is that to make a highly biodegradable product, surfactants with less branching should be used. 

The application of enzymes, however, is not novel already in 1913, Otto Rohm, founder of what would become the chemical giant Rohm and Haas, had added a proteolytic enzyme, mainly trypsin, from milled animal pancreas and dog waste to detergents. Marketed in Germany in 1914 as Burnus , this innovation was way ahead of its time and ran into several problems First, the very crude proteolytic enzyme contained many impurities which sometimes stained the very textile it was supposed to clean. Second, one tablet could be added to 10 liters of water to remove stains from clothes. Unfortunately, consumers were used to bulky washing powders which lathered a lot, and they did not believe that such a small tablet could work. Third, the process of enzyme extraction was not economical enough to include it in routine household detergents. 

Dishwash tablets have undergone a transformation in the past few years, going from a simple powder or liquid gel, to two-in-one tablets, to three-in-one tablets, to four-in-one tablets, and recently to five-in-one tablets, which were launched in 2005. This latest version comes with three sections sealed inside water soluble compartments made of the - polymer poly (vinyl alcohol). The various ingredients in a dishwash product have to be kept separate to prevent them from reacting chemically with one another. Some of the ingredients can coexist without reacting, such as the surfactants and the enzymes, as they do in laundry detergent powders, and some are most useful if they are released near the end of the wash, such as rinse aids. 

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