Dishwashing, automatic

One unusual example of a hard surface cleaner of this type claims a residual effect on the surface that reducing the cleaning effort needed on subsequent cleanings. The surprising part of this invention is that the claim is based, in part, on the presence of lipase in the formula [226], This is a rare example of the use of an enzyme in a consumer-intended hard surface cleaning formula. The use of enzymes in hand dishwashing, automatic dishwashing, and laundry is quite common. 

LABORATORY INFORMATION MANAGETffiNT SYSTEMS] (Vol 14) Automatic dishwasher compounds... 

Trisodium phosphate is strongly alkaline many of its appHcations depend on this property. For example, many heavy-duty cleaning compositions contain trisodium phosphate as a primary alkalinity source. The crystalline dodecahydrate itself is marketed as a cleaning compound and paint remover. Traditionally, trisodium phosphate has been used in water softening to remove polyvalent metal ions by precipitation as insoluble phosphates. Because the hypochlorite complex of trisodium phosphate provides solutions that are strongly alkaline and contain active chlorine, it is used in disinfectant cleaners, scouring powders, and automatic dishwashing formulations. 

About 264,000 metric tons of elemental capacity is available in North America, plus another 79,000 t (P equivalent) of purified wet phosphoric acid (14). About 85% of the elemental P is burned to P2 5 hydrated to phosphoric acid. Part of the acid (ca 21%) is used direcdy, but the biggest part is converted to phosphate compounds. Sodium phosphates account for 47% calcium, potassium, and ammonium phosphates account for 17%. Pinal apphcations include home laundry and automatic dishwasher detergents, industrial and institutional cleaners, food and beverages, metal cleaning and treatment, potable water and wastewater treatment, antifree2e, and electronics. The purified wet acid serves the same markets. 

The use of chlorinated trisodium phosphate is declining. It has been largely replaced by chlorinated isocyanurates in powdered abrasive cleansers and automatic dishwash detergents to reduce cost, improve performance, or comply with restrictions on the use of phosphates. Some chlorinated trisodium phosphate is stiU used in commercial laundries and in disinfectant cleaners. 

Most of the CA produced commercially is chlorinated to produce SDCC, SDCC-H, PDCC, TCCA, and the double salt TCCA4PDCC. These have become standard ingredients in formulations for scouring powders, household bleaches, institutional and industrial cleansers, automatic dishwasher compounds, and general sanitizers, and most importantly, in swimming pool and spa/hot tub disinfection. The choice of chloroisocyanurate for any particular... 

The chloroisocyanurates can be used in the bleaching of cotton, synthetics, and their blends they do, however, attack proteinaceous fibers, such as silk or wool, presumably via active chlorine reaction with the peptide (amide) linkage. However, the chloroisocyanurates can be used as shrink-proofing agents in wool finishing (131), (see Textiles Wool). The same action of chlorine upon proteins contributes to the effectiveness of chloroisocyanurates in automatic dishwashers. 

Phospha.tes, Pentasodium triphosphate [7758-29-4] sodium tripolyphosphate, STPP, Na P O Q, is the most widely used and most effective builder in heavy-duty fabric washing compositions (see also Phosphoric acid and phosphates). It is a strong sequestrant for calcium and magnesium, with a p c of ca 6, and provides exceUent suspending action for soils. Because of its high sequestration power, it also finds extensive appHcation in automatic-dishwashing detergents. Sodium tripolyphosphate forms stable hydrates and thus aids in the manufacture of crisp spray-dried laundry powders. 

Foam regulators such as amine oxides, alkanolamides, and betaines are present in products where high foam value is functionally or estheticaHy desirable, mainly hand-dishwashing Hquids and shampoos. In automatic dishwashing products, on the other hand, copious foam volumes interfere with the efficiency of the mechanical rotors during operation. In this type of product, a foam depressant is often present. 

Automatic Dishwashing. There are many differences between laundering and automatic dishwashing. The hard surfaces present in the latter process differ from textiles because they are impermeable to sods therefore, cleaning fluids have better access to the sods. 

Vinegar is recommended for cleaning a variety of appliances and other items that may be stained by hard water deposits. Automatic coffee makers, steam irons, dishwashers, teapots, faucet heads, and shower heads — over time, all accumulate calcium deposits from hard water. Groundwater, that is, water that travels through soil and rocks, accumulates dissolved calcium ions as a consequence of the natural weathering of minerals that contain calcium such as limestone and calcite, shells, and coral. At the same time, carbon dioxide in the air dissolves in water to form carbonate ions that combine with calcium ions to form a white solid, calcium... 

Applications focus on turbidity, conductivity, water hardness, mass, and concentration, which are measured in automatic washing and dishwashing machines. 

The turbidity level or more exactly the optical transmittance and reflectance provides a range of information about the washing and rinsing water in automatic washing and dishwashing machines. The most important parameters are soil and detergent concentration, both of which have an impact on turbidity. 

Conductivity sensors are most commonly used for safety purposes in household appliances. Presence and absence of washing liquor, detergency, and water softener can be easily measured and proper operation ensured [71]. The various applications mainly differ by their design of electrode geometry and methods for electrical measurement. Due to the close relation between ionic conductivity and water hardness, the automatic water softener in an automatic dishwasher can be controlled by a conductivity sensor [72]. To isolate the transmission of the measured value from the process controller, the conductivity sensor could incorporate an opto-electronical coupling [73]. Thus, protective insulation of the electrodes in a washer-dryer could be ensured. 

In automatic dishwashers, amount of dirt on crockery and cutlery can be measured with a radar sensor [87] or with a device that uses the reflectivity of an integrated surface [88]. Thus, the load of the washing liquor with soil and detergency can be measured. 

The relevant parameters to trigger the release of actives can be the temperature or pH-value of the washing liquor, the salt concentration or even the presence of water. In some automatic dishwashing tablets that have been recently introduced, for instance, the difference in temperature of the main wash cycle and the rinse cycle [89], or the difference in the pH-values of these two stages is utilized to trig-... 

Fig. 4.9 Temperature and pH-value (qualitatively) in the different cycles of an automatic dishwashing program and the dissolution of a tablet with temperature triggered release of rinse aid.

Automated sequencing systems, 72 510 Automatic Chemical Agent Detector and Alarm, 5 830-831 Automatic discharging suspended magnets, 75 438-439 Automatic dishwashing (ADW), 70 285 Automatic dishwashing detergents (ADDs), 70 274, 285... 

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