A Bar of Soap and Liquid Soap
The word "soap" is derived from the Latin word "sapo" which is the name of a fictitious mountain in the area of Rome which is said to be associated with soap.
Soap cleans by causing things that are insoluble, like small bacteria, chemicals, dirt or the like, to become soluble, and wash away with water.
The earliest known soap was made by the Babylonians around 2800BC.
The Ancient Egyptians regularly bathed using a soap made by combining animal fats with wood ash.
The Roman writer Pliny the Elder described soap as an invention of the Gauls for making their hair shiny.
According to Pliny the Elder, the Phoenicians were using soap as early as 600 B.C.
As early as the 1200s the process was industrialized in the Middle East.
Industrial soap production occurred in the 1450s to 1500s in France.
In 1712, England imposed a tax on soap which was not repealed until 1835.
Liquid soap was patented by the American William Sheppard in 1865.
The word soap occurs twice in the King James Bible.
The first soaps were created by boiling animal fat (or olive oil around the Mediterranean) to dryness with ashes from a wood fire, which contain potassium hydroxide. The earliest users were either the Celts (who called it saipo), or the Phoenicians.
These early soaps were generally used for cleaning clothes and for curing animal hides. The Romans used soap on their bodies as part of bathing, and they spread their soap making skills throughout Europe.
In Europe, medieval soap production centered around Marseilles and spread to Genoa and Venice. In England, there was soap production in Bristol as early as the 12th century. In the 13th and 14th Centuries, soap was created in Cheapside in London. Soap was seen as a great source of revenue by the government and it was taxed. During the Napoleonic wars this tax was as much as 3d per pound, and the tax inspectors would lock up the soap boiling pans to stop illegal production at night. This tax was not repealed until 1835, by which time the exchequer was making £1million a year from the industry.
The process of making soap remained more or less unchanged until a method of producing large quantities of sodium hydroxide (caustic soda) was discovered in the late 18th century. This opened up the manufacture of good quality soap on a large scale. By the time of the industrial revolution in the late 18th century, soap was more widely available. In fact, Pears Soap dates from 1789.
Apparently, Justus von Liebig, a German chemist, said that the amount of soap that a nation used was a measure of its wealth and civilization. (If only that were true now.)
With the addition of a few other ingredients, current methods of making soap can be used to make a genuine transparent soap, i.e.: a soap which is clear like glass.
Extra vegetable derived glycerin is added to soap to bring the glycerin content to a level of between 10 and 11%.
Fully boiled soap has the glycerin removed by adding a brine solution (salt water) to the soap. The glycerin dissolves in the water and is drained off leaving only the soap which is then dried into little flakes or "noodles"'.
Cold process soap is all in soap where there is no external heating . All the heat comes from the saponification reaction which is exothermic, an excess of heat is produced by the chemical changes in the components of the reaction. An example would be the dissolving of sodium hydroxide in water. These soaps are normally made with pure coconut oil.
The soaps produced are called hard or soft depending on what sort of fats and oils are used, and whether sodium hydroxide or potassium hydroxide is the alkali. Processing the soaps can then proceed. If the soap was made into noodles, it is milled. If it was poured into a frame while hot, it is cut.
During milling the soap chips are pushed through a machine called a plodder which mixes in color and perfume and produces a continuous extruded bar of soap. This is then cut into billets by machine.
With cut soap, the soap is cut by hand or machine from a large block down to a soap sized billet.
After the soap has been made into a billet, it is stamped. There are two kinds of die. One is a capacity die where excess soap squeezes out around the middle and cut off later. This method produces a very regular weight and size and is the way that most domestic soaps are made. The other kind is a box die (or collar die). This contains all the soap which was placed in the mould. This methods produces a less deformed (and therefore more transparent) tablet and also requires less finishing.
Opaque milled soap: This group represents the vast majority of soap produced in the world today. These soaps are made using a fully boiled process and utilize some of the most advanced soap making techniques, usually on a very large scale. After manufacture the soaps are then milled as above.
Translucent soap is a relatively modern technique which simulates the old frame method and can produce glycerin soaps which a reasonable level of glycerin (up to 4%). The benefit of this method is that it produces a glycerin soap using a large scale, automatic machine process, which is therefore more commercially attractive.
There are three ways to make transparent soaps. The first is to pour the whole making into a frame and cut up the soap from a large block. This is very labor intensive. The second way is to pour the soap into individual tubes which produces long bars of soap which then can be processed automatically. The third method is to pour soap into individual moulds, which are then cooled, and the individual soaps released. This can be a completely automatic process.
The best method is the first. Pouring into individual moulds requires the soap to be very liquid and thus the water content is very high. This in turn means that the soap is prone to melting, even more than normal glycerin soaps. Glycerin is attractive to water and there is a tendency for such soaps to absorb moisture unless kept dry.
Synthetic detergent bars are an increasing number of these cleansing bars on the market. They are made using a different chemical process to normal soap making. They were originally developed to attempt to achieve a product which is closer to pH neutral than normal soap. The first of these was Neutrogena, but there are now others available such as Dove.
Soap is famous. It has a magazine named for it and has limericks written about it, but until recently, no one has ever fully investigated world soap statistics.
Soap, a monthly magazine, published what it claims is the first soap survey. Among the findings are: The world production of soap: 10,000,000,000 lb. per year (of which the U. S. makes and uses about one-third).
· The per-capita consumption of soap: U. S., 25 lb.; Netherlands, 24 lb.; United Kingdom, 20 lb.; Japan, 7 lb.; Brazil, 6.8 lb; world average, 6.6 lb.; Russia, 5.7 lb; India, 4 oz.; China, 2 oz.
· World statistics: 92% laundry soap.
· U. S statistic: 85% laundry soap, 12% toilet soap, 3% miscellaneous.
The lather, hardness and moisturizing qualities of a soap are dependent on the various oils used in the recipe.
In 2002, an estimated 595 people in the U.K. were treated in hospital after soap-related accidents.
The U.S. gangster and con man “Soapy” Smith (1860-1898) acquired his nickname through a racket selling bars of soap allegedly containing banknotes.
A single bar of commercial bar soap may contain over 20 toxic ingredients, many of which have been connected to cancer, endocrine issues, skin problems and more.