Builders soaps

Trisodium phosphate [7601-54-9] trisodium orthophosphate, Na PO, is an important constituent of hard-surface cleaners including those for ceramic, metal, or painted surfaces. It may be used with soaps, surfactants, or other alkaHes. It precipitates many heavy-metal ions but does not sequester to form soluble chelates. It is thus a precipitant builder and additionally an alkaH. 

Consideration will first be given to the inorganic builders used to produce the base material. The pH values of several commonly used materials are shown in Table 11.1. Hydroxides are the simplest, strongest alkalis and most commonly used. A major effect of hydroxides in cleaning is saponification the conversion of certain oils and greases to water-soluble soap-type materials. Hydroxides also produce solutions of high conductivity, as required for electrocleaning. 

FIG. 20 Detergency performance of LAS/AE/soap mixtures with phosphate builder. Shaded zones represent optimum detergency performance. Conditions 38°C and 60°C, 0.5% concentration, 15% surfactant/30% builder, 150 and 300 ppm hardness, sebum soil. (From Ref. 44.)... 

Ether carboxylates are used not only in powdered detergents but in liquid laundry detergents for their hard water stability, lime soap dispersibility, and electrolyte stability they improve the suspension stability and rheology of the electrolyte builder [130,131]. Formulations based particularly on lauryl ether carboxylate + 4.5 EO combined with fatty acid salt and other anionic surfactants are described [132], sometimes in combination with quaternary compounds as softeners [133,163]. Ether carboxylates show improved cleaning properties as suds-controlling agents in formulations with ethoxylated alkylphenol or fatty alcohol, alkyl phosphate esters or alkoxylate phosphate esters, and water-soluble builders [134]. 

However, the ability to act as a builder encompasses much more than so far been mentioned. Builders influence the coagulation of solid soil, often form a buffer system, and promote the soil suspending activity of washing liquors. They are further able to reduce the catalytic effect of ferric and manganic ions. Thus they support the stabilization of peroxides in detergents. Similarly, rancidness caused by catalytic processes of soap and fragrances can be avoided. 

Compounds derived from C10 15 alkylbenzenes exhibit excellent detergency in combination with soap or with soap plus builders. 

Addition of suitable builders, such as sodium silicates or sodium tripolyphosphate, could increase the detergency of soap-LSDA blend even further. A systematic investigation of three-component systems, soap-LSDA builder, showed that a detergency maximum could be attained which corresponded to a certain fixed ratio of components. Maximum detergency corresponded to an approximate composition of 75% soap, 10% MES, and 15% metasilicate. The tests were carried out at 50°C and at 300 ppm water hardness which is well above that of U.S. municipal water supplies. The principle of detergency potentiation of soap by an LSDA and builder was always evident, even when using other artificially soiled cloths, such as those supplied by U.S. Testing Co. or Testfabrics Inc. 

Addition of as little as 5% soap to an amphoteric LSDA of limited water solubility (high Krafft point) brought about a substantial lowering of the Krafft point and thus markedly improved water solubility. On the other hand, addition of 10% of amphoteric LSDA to sodium palmitate lowered the Krafft point of the soap by 10-14°C. Addition of anionic LSDA to sodium palmitate showed smaller Krafft point depression. Addition of a builder-type salt, such as sodium metasilicate, had essentially no effect on the Krafft points of soap-LSDA mixtures. 

The concept of a soap-LSDA detergent represents a simple solution to the quest for less polluting highly efficient laundry detergents [47,48]. If present worldwide price trends for petrochemicals, phosphates, and other builders continue to rise, the use of tallow or other fats and oils, which are replenishable agricultural products or byproducts, should become economically more attractive. Since the USD A research team initiated research on soap-LSDA detergents, the a-sulfonated fatty acid esters (MES) have become commercially available in the United States, Europe, and Japan. 

Intensive investigations have shown that specific silica-silicone mixtures or paraffin oil systems are considerably more universal in their applicability and that their effectiveness is independent of both water hardness and the nature of the surfactant-builder system employed [31-33]. Therefore, most heavy-duty detergents in Europe have silicone oil and/or paraffins as foam depressors. Soap has almost lost its importance as a foam regulator. Silica-silicone systems, frequently called silicone antifoams, are usually commercially available as concentrated powders. The key silicone oils used for antifoams are dimethylpolysiloxanes. 

Suds suppressors (LD, DW, ADW, HC) Limit suds amount when suds will interfere with cleaning Sensitivity to wash temperature, water hardness, and builder system Efficiency on the surfactant system Alkyl phosphates Silicones Soap 0-5% 0-5%... 

Soap chips are made by running a thin sheet of melted soap onto a cool cylinder and scraping off the soaps in small broken pieces. Soap granules are dried miniature soap bubbles. Soap powders and scouring soaps contain some soap, a scouring agent (abrasive) such as powdered pumice or finely divided sand, and builders like sodium carbonate and trlsodlum phosphate. Builders make the soaps act more rapidly. The cleansing action of soap has been discussed in Unit 5. 

Neat soap may or may not be blended with other products before flaking or powdering. Neat soap is sometimes filtered to remove gel particles and run into a reactor (crutcher) for mixing with builders. After thorough mixing, the finished formulation is run through various mechanical operations to produce flakes and powders. Because all of the evaporated moisture goes to the atmosphere, there is no wastewater effluent. 

Alkaline cleaning solutions contain builders (sodium salts of phosphates, carbonates, silicates, and hydroxides) and surfactants (detergents and soaps). Other additives may include anti-oxidants and stabilizers as well as small amounts of solvents. Acidic cleaning solutions may contain mineral acids (nitric, sulfuric, phosphoric, or hydrochloric), organic... 

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