Soap scum removal

Hard Foaming Hard Surface Cleaner for Soap Scum Removal... 

Tests were conducted to evaluate the performance of soap scum removers with the ingredients listed in Tables 45 and 46. The soap scum was prepared by adding the hard water to the soap solution, graphite, isopropanol, and sebum, and spraying on Formica panels. For the test, two drops of the test formulation were applied (see Table 47) to at least four areas of the soiled Formica tile panel. After waiting for 30 sec, the panels were rinsed and evaluated using a scale from 0 (worst) to 4 (best) to rate the soil ranoval of each test solution. The results are given in Table 48. 

TABLE 46 Soap Scum Removal Test Materials... 

Uses Raw material rust inhibitor wetting agent for pickling baths surfactant for acid and alkaline cleaners soap scum remover coupling agent lime soap remover... 

Removes mildew stains and soap scum effectively by prolonging contact time... 

There are two solutions to soften water that is too hard. First, the water could be filtered to remove all of the calcium and magnesium ions. But this can be very expensive, so most people use a water softener instead. A water softener is a piece of equipment that can be attached to the water pipes that run into a house. This way, all the household water goes through the water softener before going into the other pipes in the house. Inside a water softener are small plastic beads. These beads have sodium ions (Na+) stuck on them. As the water flows over the bed of beads, the magnesium and calcium ions get replaced with the sodium ions. Since sodium is easily dissolved in water, it does not precipitate out in pipes like calcium and magnesium ions do. As a result, no scales form inside the pipes. Sodium ions do not react with soap to form soap scum, either, and they allow the soap to lather properly. 

One of the compounds in soap that helps produce lather is sodium stearate, NaCigH3502, which dissolves in water. In hard water, calcium ions react with the stearate ions to form calcium stearate, Ca(CigH3502)2. This material is insoluble and forms soap scum. Scum is often seen as a ring around sinks or tubs. If calcium ions are removed from the water by water softeners, soap wiU lather and no more scum wiU form. 

Acidic bathroom cleaners have some distinct advantages on common bathroom soils. First, the main matrix for the soil referred to as soap scum is soap that has been precipitated by water hardness ions. Imbedded in this matrix may be skin flakes, lint, dirt, etc. (see Figure 13.7), but the waxy precipitated soap serves to hold the mass together and make it adhere to surfaces. Acids can work to reverse this chemical reaction, turning some part of the soap fatty acids into liquid components (notably oleic acid). This serves to soften the soil overall and thereby make it more easily removed. Second, if there were any ion bridging of the soil to a receptive... 

These cleaners should not only be tested for their stain-removing ability, but also for their soap scum cleaning. Although such alkaline products generally show poor soap scum cleaning compared to the acid bathroom cleaners, many consumers use them for general bathroom/tile cleaning. 

Removes mildew stains and soap scum very effectively. Use on tile, grout, tub, tub walls, shower curtains, shower doors, garbage cans, and diaper pails. 

For example, water by itself will not remove some oils from skin, but addition of a sodium salt of stearic acid (a common hand soap) lowers the surface tension of water allowing the oil to be emulsified. Soap is less dense than water and the action of washing aerates the mixture so that the soap scum (soil and soap products) float to the surface. 

The inside surface of the dishwasher becomes covered with residue over time. These residues include lime scale, soap scum, and food deposits. The removal of lime scale from the dishwasher has been the main concern of patent inventions, because lime scale residues deposit on the heating elements and reduce the overall heat exchange of the systems. However, soap scum and food deposits have also been seen as a problem because these can redeposit on the dishes as well as reduce the effectiveness of the detergent. In 2006, Binder obtained a patent that reportedly targets all three types of deposits left in the dishwasher. The detergent tablet contains 10-75% of a limescale remover acid, 11-20% nonionic surfactant, and from 0 to —5% of a detergency enzyme. 

Household cleaners are generally used on every hard surface in the home except for dishes. In this chapter, the discussion concentrates on specialty cleaners that are formulated for specific cleaning problems, whereas all-purpose cleaners and their variants are covered in Chapter 2. This means that most of this chapter will be spent discussing cleaners used in the bathroom—such as soap scum cleaners, mildew removers, and toilet bowl cleaners. Additionally, there are cleaners that are used for extremely narrow use, such as oven and drain cleaners. Disinfectant cleaners as variants of all-purpose cleaning were covered in the previous chapter, but will also be covered here with the emphasis on the disinfectant action rather than on the cleaning function. 

Most of the specialty cleaners that are formulated for household use are intended for the bathroom. Although hard water scale can occnr in any room with running water, soap scum and mildew tend to be concentrated in the bathroom. Bathroom cleaners mostly are claimed to have action against the big three of bathroom soils soap scnm, mildew (or mildew stain), and hard water buildup. These soils are best removed with specialized chemistry, and so the specialty cleaners are very successful in this area. 

Soap scum tends to be built up as fine layers of calcium or magnesium fatty acids on the bathroom surfaces, gradually dulling the surface and serving as a matrix for trapping other soils, such as sloughed skin cells, dirt, lint, and mildew. Many bathroom surfaces are fabricated to be shiny, and the soap scum, which is white or cream colored, tends to become apparent when the shine is dulled. As the more popular bathroom colors are pale or white, it is hard to see the soap scum itself on the surface, owing to the lack of color contrast. Soap scum is much more apparent on dark surfaces (like black ceramic tiles) or on transparent surfaces (like transparent shower doors). It is therefore somewhat hard for the consumer to determine that the soap scum has been completely removed from the surface except by the reappearance of the native shine of the surfaces. 

As commented previously, these cleaners depend largely on the nonsurfactant ingredients. The chemistry of the cleaner is tailored more closely to the chemistry of the soil than the chemistry of all-purpose cleaners, which seek to remove the broadest variety of soils from the widest variety of surfaces. However, in practical fact, all-purpose cleaners are generally tailored to the removal of grease. This means that they can still remove soap scum or dirt or mildew from a surface, by virtue of their surfactancy, but not to the depth or with the efficiency or ease that the specialty cleaners do. This is the raison d etre of specialty cleaners—if all-purpose cleaners were really that efficient on all surfaces, then the specialty cleaners would not exist. 

Solvents, predominately the glycol ethers, are used somewhat in these specialty cleaners. In cases like soap scum, where it is an organic soil capable of softening, the glycol ethers are useful. They serve less use in removing inorganic soils like hard water deposit, where attack by acidity is far more effective. Alcohols are also sometimes used, especially in products like the shower sprays, where the soil load is light. Alcohols could also be used to adjust the viscosity of some cleaners. Solvents are also used in wipes formulas to help speed both the action of the cleaner on the surface (since it has to work essentially within the time of a swipe) and in the evaporation of the cleaner on the surface, since these are no-rinse products. 

Features Low color easy to handle stable over pH range 5-9 no gelling when added to cold water allows quick solubilization and removal of soap scum Properties Liq. low odor sol. in water 97% cone. 

Uses Surfactant blend for hard surf, cleaners removes soap scum at neutral pH, metal ion binding capability, removes oily and particulate soil, does not fonn sur-tactant/water gels Properties Liq. 

After the temporary hardness has been removed, any calcium and magnesium which remains is still capable of forming a scum with soap, and can also react to form boiler scale. This is called the permanent hardness. 

Borax is used as a cleaning agent and water softener that removes ions of elements such as magnesium and calcium that cause hard water. When these hard water elements are mixed with soap, they prevent soap from sudsing and form a scum or residue that is deposited on hard surfaces. Borax can ehminate this residue ring by replacing the Mg and Ca ions with the more soluable Na and ions. Borax is the third most important boron compound. 

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