TOILETRIESSOAPS.

Personal care or toiletries is the industry which manufactures consumer products used for beautification and in personal hygiene.

Common soap bars are a 19th century invention, but soap was used in the textile industry and medicinally for at least the last 5000 years. Some snapshots of the role soap plays in our lives make for a fascinating tour back through time.

Archaelogical evidence of soap was found in Babylonian clay containers dated at 2800 B.C. Inscriptions on the containers state that the product was made from fats boiled with ashes. The product thus produced was not necessarily used to wash the body; it might have been used to wash wool used in textile manufacture.

The Ebers papyrus, 1500 B.C. refers to medicinal use of soap for skin diseases. These texts suggest that both animal and vegetable fats were combined with alkaline salts to make a substance used for treating sores as well as washing.

In short, throughout history, soap use for personal hygiene was medically motivated. However, short-cuts in manufacturing techniques achieved in the 19th century resulted in two important developments: First, a new process, using sodium

hydroxide, made for a hard rather than liquid product that was easier to store and ship.

Second, soap became easier and cheaper to make and thus became more affordable and popular.

The result was entirely predictable: public hygiene in more affluent areas of the world experienced a quantum leap.

Soap: A product that when

used with water decreases surface tension so as to loosen unwanted particles, emulsify grease, and absorb dirt and grime into foam.

Soap making is a serious occupation requiring some understanding of chemistry. Traditionally, the manufacturing of soap was a lengthy process with a considerable number of unpredictable stages. We can appreciate the difficulties if we realize that soap results from a chemical reaction between an acid and base that causes "saponification" to occur.

Typically, the acid portion of soap comes from a fat, either an animal or a vegetable fat. The alkali or base is the more precarious component because it was usually made from ashes, basically any ash from any burned organic material, but usually from wood used in cooking fires. When water drips on the ash, a brown liquid forms whose exact chemical properties would have been difficult to judge prior to the advent of pH testing devices.

"Saponification" is another word of Latin origin. It refers to Sapo Hill, which according to legend is a place above the Tiber where animal sacrifices were made though some think Mount Sappo was a place in Greece. Women washing their clothes in the river below this place found that less effort was needed to clean them where there was run-off from the temple on the hill. What had happened was that fat had boiled over into the fires and remained in the ashes. When the residues of the burnt offerings were exposed to rain water, the mixture of fat and ashes formed a "natural" soap that traveled into the river below where the sacrifices

Acid Alkali

Normal pH is 7.0Water should be 7.0

Acids are chemicals with a pH lower than "neutral". An acid may be mild or extremely caustic.

Alkaline substances have a pH higher than 7.0. They may be mild or corrosive.

The type of acid used to make soap is a fatty acid, either from animal fat or vegetable oil.

The alkali used to cause the chemical reaction with the fatty acids is either made from potash (lye water) or sodium hydroxide.

Saponification

When a base reacts with a fat or oil, fatty acids are separated from the glycerin and the sodium or potassium component of the alkali bonds with the fatty acids. The product formed by the sodium or potassium and the fatty acids is a salt. Technically speaking, soap is a salt. Glycerin (also called glycerol) is a by-product that also has cleansing properties. It is hydroscopic, i.e. moisturizing because it attracts water from the air.

Animal Fat: Most inexpensive soaps are by-products of the

meat packing industry. There are, however, a large number of reasons for preferring vegetable-based soaps over animal ones, not the least of which is that toxins, including synthetic hormones used to bulk up animals, tend to accumulate in fat tissue. If this were not a cogent enough argument, it is fairly easy to demonstrate that animal fats tend to clog pores more than vegetable oils. Even going back many centuries, soaps made from vegetable oils, like Castile soap, were regarded as superior to those made from lard.

Animal fat has to be "rendered" or purified. This involves cooking and odor. Meat has to be separated from the fat. This is usually done by heating the fat so that the cracklings separate. The meat looks like it has been cooked, which, of course, it has. The meat must be removed. Sometimes, water has to be added so that it absorbs the impurities. Then, the "soup" has to cooled, usually slowly, so that the fat separates and rises to the top while the heavier parts sink. The fat is then skimmed off. If the fat still has odor and impurities, the process has to be repeated.

Vegetable Oils:

However, almost any vegetable oil can be used. The more common ones are almond, avocado, jojoba, palm, and shea butter.

In Spain, there was a tradition of fine soap making, called Castile because of the place name. These soaps used mainly olive oil. Today, coconut oil, sometimes called coconut butter, is used in many soaps because it lathers nicely and is almost odorless.

Lye Water:

If it is too corrosive, more water needs to be added. This is a time consuming process that requires burning one's own organic materials over an open fire or in a cast iron pot. If a feather dissolves in the lye, the pH is probably about right. Some try floating eggs or potatoes in the brew. These objects should float so that half their mass is below the water line.

This kind of base will make a soft soap, not a hard soap.

As noted, this is made by pouring or dripping water over ashes. Different woods or other organic materials produce variations in color. Soft water, i.e., rain or spring water, should be used. If the solution does not have a high enough pH, it needs to be poured over more ash.

Caustic Soda:

Sodium hydroxide is a nasty chemical that requires special handling, like safety goggles and gloves. It was introduced in the 19th century by a French chemist named Nicolas Leblanc (1742-1806) and improved by a Belgian chemist, Ernest Solvay (1836-1922), who changed the nature of the soap and impacted the industry radically. Basically, the newer methods substituted sodium hydroxide for the lye water made from potash. The result was a hard soap that was easy to store and ship. Soap making moved from the farm to industrial manufacturers who realized huge profits from the recycling of animal fats into commercially viable cakes that were easy to sell.

Other Ingredients: As everyone knows, there can be a lot of ingredients in soap:

chemical stabilizers, preservatives, fragrances, vitamins, seaweed, corn, oatmeal, pumice, aloe, dyes, milk, fruit or berries, cucumbers or carrots or other vegetables, exotic oils, beeswax, herbs and flowers . . . Each ingredient changes the chemistry of the bar of soap. Let's see how clear I can be. Milk, from goats or other animals, counts towards the acid (and water) component of the soap. Aloe gel counts towards the base component and enhances the disinfecting properties of the soap.

Intuitive people as well as those who are cutting edge in new ecological developments must realize that each constituent not only has to go through some process to prepare it for use in the soap but each one changes the pH of the soap—and our environment—because even if run-off today does not start in a temple where animal sacrifices are performed, it starts with animal sacrifice and ends up laced with antibiotics and derivatives of the petrochemical industry that eventually end up in sewage and septic systems.

Commercial Soap

Dial is a good example of a commercial soap. It is produced by Armour, but it is a truly distant cousin of Borax, a cleanser that went into production after the discovery of vast deposits of borax in Death Valley during the Gold Rush in 1880. The Armour family went into the soap business eight years later. Then, it produced a scouring pad for aluminum cookware called Brillo (1913). Purex began in a garage in Los Angeles in 1922. Enter the meatpacking industry: Dial is introduced in 1948 as the first antibacterial soap. The ad campaign was enormous and promised 24-hour protection from bacteria-causing odors. Next comes Vienna sausage in aluminum containers . . . beginning to see a flash back of your childhood?

Let me continue. In 1988, while the former host of "Death Valley Days" was sitting in the Oval Office, the rights to market 20-mule team of Boraxo were acquired. Next came the first microwave cup meals. A year later, Liquid Dial is introduced. It rings up a million in sales in the first 10 weeks on the market. The deal with WalMart took another decade to pull together. In the meantime, the company split and spun off some products and acquired new ones.

Soap versus Detergent

A detergent is a synthetic imitation of a soap, i.e. a laundering agent made from chemicals. Detergents were developed in Germany in 1916. They are not just "imitation soaps." Detergents are different from soaps in that they do not combine with natural mineral salts in water and do not form scum. Unlike real soap, detergents work in cold water and with salt water. Soap and detergent have similar capacities to emulsify fats and oils and to hold dirt, but from this point on, they are significantly different due to the presence of surfactants and additives, such as whitening agents. The list of the chemicals used to produce these detergent effects is hair raising.

Beginning around 1960, it was noted that there was more foam on rivers and that sewage treatment facilities were encountering serious problems, including that water foamed when it came out of the tap, this due to the fact that propylene-based alkyl benzene sulphonates are not completely degraded by the bacteria naturally present in effluents. It is not for me to try to explain the chemistry of all that started to go wrong, but merely to note that the correction being sought was to increase use of proteolytic enzymes to aid the breakdown of materials that were not readily "bio-degradable." The ramifications of this are almost too far-reaching to imagine.

Manufacture of soap began in England around the end of the 12th century. Soap-makers had to pay a heavy tax on all the soap they produced. The tax collector locked the lids on soap boiling pans every night to prevent illegal soap manufacture after hours. Because of the high tax, soap was a luxury item, and it did not come into common use in England until after the tax was repealed in 1853. In the 19th century, soap was affordable and popular throughout Europe.

Early soap manufacturers simply boiled a solution of wood ash and animal fat. A foam substance formed at the top of the pot. When cooled, it hardened into soap. Around 1790, French soapmaker Nicolas Leblanc developed a method of extracting caustic soda (sodium hydroxide) from common table salt (sodium chloride), replacing the wood ash element of soap. The French chemist Eugene-Michel Chevreul put the soap-forming process (called in English saponification) into concrete chemical terms in 1823. In saponification, the animal fat, which is chemically neutral, splits into fatty acids, which react with alkali carbonates to form soap, leaving glycerin as a byproduct. Soap was made with industrial processes by the end of the 19th century, though people in rural areas, such as the pioneers in the western United States, continued to make soap at home.

Raw Materials

Soap requires two major raw materials: fat and alkali. The alkali most commonly used today is sodium hydroxide. Potassium hydroxide can also be used. Potassium-based soap creates a more water-soluble product than sodium-based soap, and so it is called "soft soap." Soft soap, alone or in combination with sodium-based soap, is commonly used in shaving products.

Animal fat in the past was obtained directly from a slaughterhouse. Modern soapmakers use fat that has been processed into fatty acids. This eliminates many impurities, and it produces as a byproduct water instead of glycerin. Many vegetable fats, including olive oil, palm kernel oil, and coconut oil, are also used in soap making.

Additives are used to enhance the color, texture, and scent of soap. Fragrances and perfumes are added to the soap mixture to cover the odor of dirt and to leave behind a fresh-smelling scent. Abrasives to enhance the texture of soap include talc, silica, and marble pumice (volcanic ash). Soap made without dye is a dull grey or brown color, but modern manufacturers color soap to make it more enticing to the consumer.

The above illustrations show the kettle process of making soap.

The Manufacturing Process

The kettle method of making soap is still used today by small soap manufacturing companies. This process takes from four to eleven days to complete, and the quality of each batch is inconsistent due to the variety of oils used. Around 1940, engineers and scientists developed a more efficient manufacturing process, called the continuous process. This procedure is employed by large soap manufacturing companies all around the world today. Exactly as the name states, in the continuous process soap is produced continuously, rather than one batch at a time. Technicians have more control of the production in the continuous process, and the steps are much quicker than in the kettle method—it takes only about six hours to complete a batch of soap.

The Kettle Process

Boiling 1 Fats and alkali are melted in a kettle, which is a steel tank

that can stand three stories high and hold several thousand pounds of material. Steam coils within the kettle heat the batch and bring it to a boil. After boiling, the mass thickens as the fat reacts with the alkali, producing soap and glycerin.

Salting 2 The soap and glycerin must now be separated. The

mixture is treated with salt, causing the soap to rise to the top and the glycerin to settle to the bottom. The glycerin is extracted from the bottom of the kettle.

Strong change 3 To remove the small amounts of fat that have not saponified, a strong

caustic solution is added to the kettle. This step in the process is called "strong change." The mass is brought to a boil again, and the last of the fat turns to soap. The batch may be given another salt treatment at this time, or the manufacturer may proceed to the next step.

Pitching 4 The next step is called "pitching." The soap in the kettle is boiled

again with added water. The mass eventually separates into two layers. The top layer is called "neat soap," which is about 70% soap and 30% water. The lower layer, called "nigre," contains most of the impurities in the soap such as dirt and salt, as well as most of the water. The neat soap is taken off the top. The soap is then cooled. The finishing process is the same as for soap made by the continuous process.

The Kettle Process

Developed around 1940 and used by today's major soap-making companies, the above illustrations show the continuous process of

making soap.

Splitting 1 The first step of the continuous process splits natural fat into fatty

acids and glycerin. The equipment used is a vertical stainless steel column with the diameter of a barrel called a hydrolizer. It may be as tall as 80 feet (24 m). Pumps and meters attached to the column allow precise measurements and control of the process. Molten fat is pumped into one end of the column, while at the other end water at high temperature (266°F [130°C]) and pressure is introduced. This splits the fat into its two components. The fatty acid and glycerin are pumped out continuously as more fat and water enter. The fatty acids are then distilled for purification.

Mixing 2 The purified fatty acids are next mixed with a precise amount of alkali

to form soap. Other ingredients such as abrasives and fragrance are also mixed in. The hot liquid soap may be then whipped to incorporate air.

The Continuous Process

The Continuous Process

Cooling and finishing 3 The soap may be poured into molds and allowed to harden into a

large slab. It may also be cooled in a special freezer. The slab is cut into smaller pieces of bar size, which are then stamped and wrapped. The entire continuous process, from splitting to finishing, can be accomplished in several hours.

Milling 4 Most toiletry soap undergoes additional processing called milling.

The milled bar lathers up better and has a finer consistency than non-milled soap. The cooled soap is fed through several sets of heavy rollers (mills), which crush and knead it. Perfumes can best be incorporated at this time because their volatile oils do not evaporate in the cold mixture. After the soap emerges from the mills, it is pressed into a smooth cylinder and extruded. The extruded soap is cut into bar size, stamped and wrapped.

Byproducts

Glycerin is a very useful byproduct of soap manufacture. It is used to make hand lotion, drugs, and nitroglycerin, the main component of explosives such as dynamite.