Translucent soaps

Milk sugar, 23 487-488 Milled bar process, in bar soap manufacture, 22 750-751 Milled translucent soaps, 22 747 Millets, in ruminant feeds, 10 864 Mill hardened copper alloys, 7 723t Milling... 

For both saponification and neutralization reactions, sodium hydroxide is the most commonly used base. In some special situations, such as the manufacture of transparent and translucent soaps, potassium hydroxide and triethanolamine are also employed. 

Lately, purely for aesthetic reasons, transparent and translucent soaps are gaining popularity, especially in South America. Stearic acid and triple pressed stearic acids can be used to produce soaps having good transparency. High palmitic acid content, however, appears to reduce transparency (130). The crystals of transparent/ translucent soaps based on palm kernel oil and pahn fatty acids are found to be in the p form (131). 

Chem. Descrip. Soap base derived from tallow (80%) and lauric (20%) sources Uses Translucent soap base for prep, of specialty soaps for personal care Properties 67% total fatty matter 15% water Prisavon 1984 [Croda Inc]... 

It would be incomplete for any discussion of soap crystal phase properties to ignore the colloidal aspects of soap and its impact. At room temperature, the soap—water phase diagram suggests that the soap crystals should be surrounded by an isotropic Hquid phase. The colloidal properties are defined by the size, geometry, and interconnectiviness of the soap crystals. Correlations between the coUoid stmcture of the soap bar and the performance of the product are somewhat quaUtative, as there is tittle hard data presented in the literature. However, it might be anticipated that smaller crystals would lead to a softer product. Furthermore, these smaller crystals might also be expected to dissolve more readily, leading to more lather. Translucent and transparent products rely on the formation of extremely small crystals to impart optical clarity. 

The characteristics of the neat soap aie controlled easily by accurately governing the composition of the alkaline solution used. Normal hydrolyzer neat soap contains about 69% actual soap, 30% water, and less than 1% NaQ, plus other stabilizers. Neat soap is a uniform, translucent, white, viscous fluid at 180-200 (82-93°C). 

Microemulsions are a special class of dispersions (transparent or translucent) which actually have little in common with emulsions, and are better described as swollen micelles. The term microemulsion was first introduced by Hoar and Schulman [1,2] who discovered that the titration of a milky emulsion (stabilised by a soap, such as potassium oleate) with a medium-chain alcohol such as pentanol or hexanol led to the production of a transparent or translucent system. A schematic representation of the titration method adopted by Schulman and coworkers is given below ... 

The violence of the ebullition gradually diminishes, but in its stead a whistling noise is perceived in the kettle. One of the planks is removed from time to time, and the soap examined when, if large and perfectly translucent bubbles rise up, the soap is finished, ind the fire is therefore extinguished. The wooden planks are next removed to allow the soap to cool, and a few buckets of soap ley are poured into me kettle. The soap is now ready to tie put into the frames, and care is taken that as little ley as possible enters the frames. 

Mr. 6. W. Sogers s Process.—Sy another process, namely, that of Mr. GF, W. Rogers of Lancaster, N, T., soap is made under pressure at a lhigh temperature adopted in the above and similar systems, by which the inventor states there is a saving of tune, inasmuch as the soap can be made in from fifteen to twenty-five minutes, with complete saponification. By this plan, moreover, the materials become bleached thus enablin g inferior goods to be employed in the manufacture. The materials are mixed in a tank heated by steam, and the mass thus prepared is run into an iron cylinder capable of holding one or more tons, and subjected to a pressure of about 400 Iba. to the square inch by means of a force-pump driven by steam. The mass is kept in this cylinder until saponification is complete, when it is run into frames. By this system any of the usual combinations of fatty matters may be employed, and the product is said to be both firm and translucent. It should be observed that in both processes given carbonate of soda is used instead of caustic soda, which also renders the employment of common salt unnecessary. 

Opacifiers. In the absence of opacifiers, products look translucent and it is difficult to control the color of the bar. Titanium dioxide is the main opacifier used in bar soaps. Owing to an exceptionally high refractive index, fine particles of titanium dioxide strongly scatter light, and effectively opacify the product [41]. 

Equipment for manufacturing transparent soap can have very different specifications where translucency is achieved by applying the right amount of mechanical work on the soap mass within a narrow range of temperature. The actual technology used to achieve translucency varies from manufacturer to manufacturer, but the principle of shearing/mechanical work that leads to phase transformation and translucency remains similar. Besides having extruded transparent soaps with... 

Kemper, H.C. and Sidebotham, R.R, Translucent and Transparent Soaps—Theory, Formulation and Processing, AOCS Meeting, October 1997. 

When oil from the head of a sperm whale is cooled, spermaceti, a translucent wax with a white, pearly luster, crystallizes from the mixture. Spermaceti, which makes up 11% of whale oil, is composed mainly of hexadecyl hexadecanoate (cetyl palmitate). At one time, spermaceti was widely used in the making of cosmetics, fragrant soaps, and candles. Draw a structural formula of cetyl palmitate. (See Example 14.1)... 

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