![Sodium laureth sulfate structure](https://upload.wikimedia.org/wikipedia/commons/6/6f/Sodium_laureth_sulfate_structure.svg)
Soap is a
salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...
of a
fatty acid
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...
used in a variety of cleansing and lubricating products. In a domestic setting, soaps are
surfactants usually used for
washing
Washing is a method of cleaning, usually with water and soap or detergent. Washing and then rinsing both body and clothing is an essential part of good hygiene and health.
Often people use soaps and detergents to assist in the emulsification o ...
,
bathing
Bathing is the act of washing the body, usually with water, or the immersion of the body in water. It may be practiced for personal hygiene, religious ritual or therapy, therapeutic purposes. By analogy, especially as a recreational activity, the ...
, and other types of
housekeeping
Housekeeping is the management and routine support activities of running an organised physical institution occupied or used by people, like a house, ship, hospital or factory, such as tidying, cleaning, cooking, routine maintenance, shopping, ...
. In industrial settings, soaps are used as
thickener
A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering their t ...
s, components of some
lubricants, and precursors to
catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
s.
When used for cleaning, soap
solubilizes particles and grime, which can then be separated from the article being cleaned. In
hand washing
Hand washing (or handwashing), also known as hand hygiene, is the act of cleaning one's hands with soap or handwash and water to remove viruses/bacteria/microorganisms, dirt, grease, or other harmful and unwanted substances stuck to the hands ...
, as a surfactant, when lathered with a little water, soap kills
microorganism
A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...
s by disorganizing their membrane
lipid bilayer
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells. The cell membranes of almost all organisms and many vir ...
and
denaturing their
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
s. It also
emulsifies
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although ...
oils, enabling them to be carried away by running water.
Soap is created by mixing fats and oils with a
base. A similar process is used for making
detergent which is also created by combining chemical compounds in a mixer.
Humans have used soap for millennia. Evidence exists for the production of soap-like materials in ancient
Babylon around 2800 BC.
Types
![Decorative Soaps](https://upload.wikimedia.org/wikipedia/commons/b/b5/Decorative_Soaps.jpg)
Since they are salts of fatty acids, soaps have the general formula (
RCO2−)
nM
n+ (Where R is an
alkyl
In organic chemistry, an alkyl group is an alkane missing one hydrogen.
The term ''alkyl'' is intentionally unspecific to include many possible substitutions.
An acyclic alkyl has the general formula of . A cycloalkyl is derived from a cycloa ...
, M is a
metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...
and n is the charge of the
cation). The major classification of soaps is determined by the identity of M
n+. When M is
Na (Sodium) or
K (Potassium), the soaps are called toilet soaps, used for handwashing. Many metal
dication
A dication is any cation, of general formula X2+, formed by the removal of two electrons from a neutral species.
Diatomic dications corresponding to stable neutral species (e.g. formed by removal of two electrons from H2) often decay quickly into ...
s (
Mg2+,
Ca2+, and others) give
metallic soap
A metallic soap is a metallic salt of a fatty acid. Theoretically, soaps can be made of any metal, although not all enjoy practical uses. Varying the metal can strongly affect the properties of the compound, particularly its solubility.
Alkali, a ...
. When M is
Li, the result is
lithium soap
Lithium soap is a soap consisting of a lithium salt of a fatty acid. Sodium-based and potassium-based soaps are used as cleaning agents in domestic and industrial applications, whereas lithium soaps are used as components of lithium grease (white ...
(e.g.,
lithium stearate
Lithium stearate is a chemical compound with the formula LiO2C(CH2)16CH3. It is formally classified as a soap (a salt of a fatty acid). Lithium stearate is a white soft solid, prepared by the reaction of lithium hydroxide and stearic acid.
Lithiu ...
), which is used in high-performance
greases. A cation from an
organic base
An organic base is an organic compound which acts as a base. Organic bases are usually, but not always, proton acceptors. They usually contain nitrogen atoms, which can easily be protonated. For example, amines or nitrogen-containing heterocyclic ...
such as
ammonium can be used instead of a metal; ammonium
nonanoate
Pelargonic acid, also called nonanoic acid, is an organic compound with structural formula CH3(CH2)7CO2H. It is a nine-carbon fatty acid. Nonanoic acid is a colorless oily liquid with an unpleasant, rancid odor. It is nearly insoluble in water, ...
is an ammonium-based soap that is used as an herbicide.
Unlike detergents, when used in
hard water
Hard water is water that has high mineral content (in contrast with "soft water"). Hard water is formed when water percolates through deposits of limestone, chalk or gypsum, which are largely made up of calcium and magnesium carbonates, bicarbo ...
soap does not lather well and a scum of
stearate, a common ingredient in soap, forms as an insoluble precipitate.
Non-toilet soaps
Soaps are key components of most lubricating
greases and thickeners. Greases are usually
emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Altho ...
s of
calcium soap or lithium soap and
mineral oil
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils.
The name 'mineral oil' by itself is imprecise, ...
. Many other metallic soaps are also useful, including those of
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
,
sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...
, and mixtures thereof. Such soaps are also used as thickeners to increase the
viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water.
Viscosity quantifies the inte ...
of oils. In ancient times, lubricating greases were made by the addition of
lime
Lime commonly refers to:
* Lime (fruit), a green citrus fruit
* Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide
* Lime (color), a color between yellow and green
Lime may also refer to:
Botany ...
to
olive oil.
Metal soaps are also included in modern artists'
oil paint
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. The viscosity of the paint may be modified by the addition of a solvent such as turpentine or white spirit, and va ...
s formulations as a
rheology
Rheology (; ) is the study of the flow of matter, primarily in a fluid (liquid or gas) state, but also as "soft solids" or solids under conditions in which they respond with Plasticity (physics), plastic flow rather than deforming Elasticity (phy ...
modifier.
Production of metallic soaps
Most metal soaps are prepared by the hydrolysis of methane into ethanoic acid and fatty acids:
:2 RCO
2 H +
CaO Cao or CAO may refer to:
Mythology
*Cao (bull), a legendary bull in Meitei mythology
Companies or organizations
* Air China Cargo, ICAO airline designator CAO
*CA Oradea, Romanian football club
*CA Osasuna, Spanish football club
*Canadian Assoc ...
→ (RCO
2)
2 Ca +
H2O
Toilet soaps
In a domestic setting, "soap" usually refers to what is technically called a toilet soap, used for household and personal cleaning. When used for cleaning, soap solubilizes particles and grime, which can then be separated from the article being cleaned.
The insoluble oil/fat molecules become associated inside
micelle
A micelle () or micella () (plural micelles or micellae, respectively) is an aggregate (or supramolecular assembly) of surfactant amphipathic lipid molecules dispersed in a liquid, forming a colloidal suspension (also known as associated coll ...
s, tiny spheres formed from soap molecules with polar
hydrophilic
A hydrophile is a molecule or other molecular entity that is attracted to water molecules and tends to be dissolved by water.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon'' Oxford: Clarendon Press.
In contrast, hydrophobes are ...
(water-attracting) groups on the outside and encasing a
lipophilic
Lipophilicity (from Greek λίπος "fat" and φίλος "friendly"), refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such non-polar solvents are themselves lipo ...
(fat-attracting) pocket, which shields the oil/fat molecules from the water making it soluble. Anything that is soluble will be washed away with the water.
Production of toilet soaps
The production of toilet soaps usually entails
saponification
Saponification is a process of converting esters into soaps and alcohols by the action of aqueous alkali (for example, aqueous sodium hydroxide solutions). Soaps are salts of fatty acids, which in turn are carboxylic acids with long carbon chains. ...
of
triglyceride
A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''wikt:tri-#Prefix, tri-'' and ''glyceride'').
Triglycerides are the main constituents of body fat in humans and other ...
s, which are vegetable or animal oils and fats. An alkaline solution (often
lye
A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions. "Lye" most commonly refers to sodium hydroxide (NaOH), but historically has been u ...
or
sodium hydroxide) induces saponification whereby the triglyceride fats first
hydrolyze
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.
Biological hydrolysis ...
into salts of fatty acids.
Glycerol
Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...
(glycerin) is liberated. The glycerin can remain in the soap product as a softening agent, although it is sometimes separated.
[Cavitch, Susan Miller. ''The Natural Soap Book''. Storey Publishing, 1994 .]
The type of alkali metal used determines the kind of soap product.
Sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable ...
soaps, prepared from
sodium hydroxide, are firm, whereas
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosph ...
soaps, derived from
potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash.
Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which exp ...
, are softer or often liquid. Historically, potassium hydroxide was extracted from the ashes of
bracken
Bracken (''Pteridium'') is a genus of large, coarse ferns in the family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that have alternating generations, large plants that produce spores and small plants that produce sex cells (eggs ...
or other plants. Lithium soaps also tend to be hard. These are used exclusively in
greases.
For making toilet soaps,
triglyceride
A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''wikt:tri-#Prefix, tri-'' and ''glyceride'').
Triglycerides are the main constituents of body fat in humans and other ...
s (oils and fats) are derived from coconut, olive, or palm oils, as well as
tallow
Tallow is a rendered form of beef or mutton fat, primarily made up of triglycerides.
In industry, tallow is not strictly defined as beef or mutton fat. In this context, tallow is animal fat that conforms to certain technical criteria, includ ...
.
[David J. Anneken, Sabine Both, Ralf Christoph, Georg Fieg, Udo Steinberner, Alfred Westfechtel "Fatty Acids" in Ullmann's ''Encyclopedia of Industrial Chemistry'' 2006, Wiley-VCH, Weinheim. ] Triglyceride is the chemical name for the tri
ester
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides a ...
s of fatty acids and
glycerin
Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...
. Tallow, ''i.e.,''
rendered fat, is the most available triglyceride from animals. Each species offers quite different fatty acid content, resulting in soaps of distinct feel. The seed oils give softer but milder soaps. Soap made from pure
olive oil, sometimes called
Castile soap or
Marseille soap
Marseille soap or ''Savon de Marseille'' () is a traditional hard soap made from vegetable oils that has been produced around Marseille, France, for about 600 years. The first documented soapmaker was recorded there in about 1370. By 1688, Loui ...
, is reputed for its particular mildness. The term "Castile" is also sometimes applied to soaps from a mixture of oils, but a high percentage of olive oil.
History
Ancient Middle East
![MODOAmigo](https://upload.wikimedia.org/wikipedia/commons/f/f7/MODOAmigo.jpg)
It is uncertain as to who were the first to invent soap. The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BC in ancient
Babylon. A formula for making soap was written on a
Sumerian clay tablet around 2500 BC; the soap was produced by heating a mixture of oil and
wood ash
Wood ash is the powdery residue remaining after the combustion of wood, such as burning wood in a fireplace, bonfire, or an industrial power plant. It is largely composed of calcium compounds along with other non-combustible trace elements presen ...
, the earliest recorded chemical reaction, and used for washing
woolen
Woolen (American English) or woollen (Commonwealth English) is a type of yarn made from carded wool. Woolen yarn is soft, light, stretchy, and full of air. It is thus a good insulator, and makes a good knitting yarn. Woolen yarn is in contrast t ...
clothing.
The
Ebers papyrus (Egypt, 1550 BC) indicates the
ancient Egyptians used soap as a medicine and combined animal fats or vegetable oils with a
soda ash
Sodium carbonate, , (also known as washing soda, soda ash and soda crystals) is the inorganic compound with the formula Na2CO3 and its various hydrates. All forms are white, odourless, water-soluble salts that yield moderately alkaline solutions ...
substance called
Trona
Trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, Na2CO3•2NaHCO3•3H2O) is a non-marine evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced ...
to create their soaps.
Egyptian documents mention a similar substance was used in the preparation of
wool
Wool is the textile fibre obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have properties similar to animal wool. ...
for weaving.
In the reign of
Nabonidus (556–539 BC), a recipe for soap consisted of ''uhulu''
shes cypress iland sesame
eed oil"for washing the stones for the servant girls".
In the Southern Levant, the ashes from
barilla plants, such as species of
Salsola
''Salsola'' is a genus of the subfamily Salsoloideae in the family Amaranthaceae. The genus ''sensu stricto'' is distributed in central and southwestern Asia, North Africa, and the Mediterranean. A common name of various members of this genus and ...
, saltwort (''
Seidlitzia rosmarinus
''Seidlitzia rosmarinus'' is a perennial-green desert species of saltwort in the Amaranthaceae family. It is endemic to the lower Jordan Valley along the Dead Sea, in Israel and Jordan, and in the Syrian desert, Central Iraq (near Najaf) and in ...
'') and ''
Anabasis
Anabasis (from Greek ''ana'' = "upward", ''bainein'' = "to step or march") is an expedition from a coastline into the interior of a country. Anabase and Anabasis may also refer to:
History
* ''Anabasis Alexandri'' (''Anabasis of Alexander''), a ...
'', were used in soap production, known as
potash
Potash () includes various mined and manufactured salts that contain potassium in water-soluble form. . Traditionally, olive oil was used instead of animal lard throughout the
Levant
The Levant () is an approximate historical geographical term referring to a large area in the Eastern Mediterranean region of Western Asia. In its narrowest sense, which is in use today in archaeology and other cultural contexts, it is ...
, which was boiled in a copper cauldron for several days.
As the boiling progresses, alkali ashes and smaller quantities of
quicklime were added, and constantly stirred.
In the case of lard, it required constant stirring while kept lukewarm until it began to trace. Once it began to thicken, the brew was poured into a mold and left to cool and harden for two weeks. After hardening, it was cut into smaller cakes. Aromatic herbs were often added to the rendered soap to impart their fragrance, such as
yarrow
''Achillea millefolium'', commonly known as yarrow () or common yarrow, is a flowering plant in the family Asteraceae. Other common names include old man's pepper, devil's nettle, sanguinary, milfoil, soldier's woundwort, and thousand seal.
The ...
leaves,
lavender
''Lavandula'' (common name lavender) is a genus of 47 known species of flowering plants in the mint family, Lamiaceae. It is native to the Old World and is found in Cape Verde and the Canary Islands, and from Europe across to northern and easte ...
,
germander
''Teucrium'' is a cosmopolitan genus of flowering plants in the family Lamiaceae, commonly known as germanders. Plants in this genus are perennial herbs or shrubs, with branches that are more or less square in cross-section, leaves arranged in op ...
, etc.
Roman Empire
Pliny the Elder, whose writings chronicle life in the First Century AD, describes soap as ‘an invention of the Gauls'.
The word ''sapo'', Latin for soap, likely was borrowed from an early Germanic language and is
cognate with Latin ''sebum'', "
tallow
Tallow is a rendered form of beef or mutton fat, primarily made up of triglycerides.
In industry, tallow is not strictly defined as beef or mutton fat. In this context, tallow is animal fat that conforms to certain technical criteria, includ ...
". It first appears in
Pliny the Elder
Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic ' ...
's account, ''
Historia Naturalis'', which discusses the manufacture of soap from tallow and ashes. There he mentions its use in the treatment of
scrofulous sores, as well as among the
Gauls
The Gauls ( la, Galli; grc, Γαλάται, ''Galátai'') were a group of Celtic peoples of mainland Europe in the Iron Age and the Roman period (roughly 5th century BC to 5th century AD). Their homeland was known as Gaul (''Gallia''). They s ...
as a dye to redden hair which the men in
Germania were more likely to use than women. The Romans avoided washing with harsh soaps before encountering the milder soaps used by the Gauls around 58 BC.
Aretaeus of Cappadocia
Aretaeus ( grc-gre, Ἀρεταῖος) is one of the most celebrated of the ancient Greek physicians. Little is known of his life. He presumably was a native or at least a citizen of Cappadocia, a Roman province in Asia Minor (modern day Tur ...
, writing in the 2nd century AD, observes among "Celts, which are men called Gauls, those alkaline substances that are made into balls
..called ''soap''". The Romans' preferred method of cleaning the body was to massage oil into the skin and then scrape away both the oil and any dirt with a
strigil. The standard design is a curved blade with a handle, all of which is made of metal.
The 2nd-century AD physician
Galen
Aelius Galenus or Claudius Galenus ( el, Κλαύδιος Γαληνός; September 129 – c. AD 216), often Anglicized as Galen () or Galen of Pergamon, was a Greek physician, surgeon and philosopher in the Roman Empire. Considered to be one ...
describes soap-making using lye and prescribes washing to carry away impurities from the body and clothes. The use of soap for personal cleanliness became increasingly common in this period. According to Galen, the best soaps were Germanic, and soaps from Gaul were second best.
Zosimos of Panopolis
Zosimos of Panopolis ( el, Ζώσιμος ὁ Πανοπολίτης; also known by the Latin name Zosimus Alchemista, i.e. "Zosimus the Alchemist") was a Greco-Egyptian alchemist and Gnostic mystic who lived at the end of the 3rd and beginning ...
, ''circa'' 300 AD, describes soap and soapmaking.
Ancient China
A detergent similar to soap was manufactured in ancient China from the seeds of
Gleditsia sinensis.
Another traditional detergent is a mixture of pig pancreas and plant ash called ''zhuyizi'' (). True soap, made of animal fat, did not appear in China until the modern era.
Soap-like detergents were not as popular as ointments and creams.
Middle East
Hard toilet soap with a pleasant smell was produced in the
Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (Europ ...
during the
Islamic Golden Age
The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is traditionally understood to have begun during the reign ...
, when soap-making became an established industry. Recipes for soap-making are described by
Muhammad ibn Zakariya al-Razi (c. 865–925), who also gave a recipe for producing
glycerine
Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known ...
from
olive oil. In the Middle East, soap was produced from the interaction of
fatty oil
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
s and
fat
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
s with
alkali. In
Syria, soap was produced using olive oil together with alkali and
lime
Lime commonly refers to:
* Lime (fruit), a green citrus fruit
* Lime (material), inorganic materials containing calcium, usually calcium oxide or calcium hydroxide
* Lime (color), a color between yellow and green
Lime may also refer to:
Botany ...
. Soap was exported from Syria to other parts of the
Muslim world
The terms Muslim world and Islamic world commonly refer to the Islamic community, which is also known as the Ummah. This consists of all those who adhere to the religious beliefs and laws of Islam or to societies in which Islam is practiced. I ...
and to Europe.
Ahmad Y. al-Hassan
Ahmad Yousef Al-Hassan ( ar, links=no, أحمد يوسف الحسن) (June 25, 1925 – April 28, 2012) was a Palestinian/Syrian/Canadian historian of Arabic and Islamic science and technology, educated in Jerusalem, Cairo, and London with a PhD i ...
(2001)
''Science and Technology in Islam: Technology and applied sciences'', pages 73-74
, UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It ...
A 12th-century document describes the process of soap production. It mentions the key ingredient,
alkali, which later became crucial to modern chemistry, derived from ''al-qaly'' or "ashes".
By the 13th century, the manufacture of soap in the Middle East had become virtually industrialized, with sources in
Nablus,
Fes
Fez or Fes (; ar, فاس, fās; zgh, ⴼⵉⵣⴰⵣ, fizaz; french: Fès) is a city in northern inland Morocco and the capital of the Fès-Meknès administrative region. It is the second largest city in Morocco, with a population of 1.11 mi ...
,
Damascus, and
Aleppo.
Medieval Europe
![Marseiller Seife](https://upload.wikimedia.org/wikipedia/commons/a/a9/Marseiller_Seife.jpg)
Soapmakers in
Naples
Naples (; it, Napoli ; nap, Napule ), from grc, Νεάπολις, Neápolis, lit=new city. is the regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 909,048 within the city's adminis ...
were members of a
guild
A guild ( ) is an association of artisans and merchants who oversee the practice of their craft/trade in a particular area. The earliest types of guild formed as organizations of tradesmen belonging to a professional association. They sometimes ...
in the late sixth century (then under the control of the
Eastern Roman Empire
The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantin ...
), and in the eighth century, soap-making was well known in Italy and Spain.
[Anionic and Related Lime Soap Dispersants, Raymond G. Bistline Jr., in ''Anionic Surfactants: Organic Chemistry'', Helmut Stache, ed., Volume 56 of Surfactant science series, CRC Press, 1996, chapter 11, p. 632, .] The
Carolingian capitulary
A capitulary (Medieval Latin ) was a series of legislative or administrative acts emanating from the Frankish court of the Merovingian and Carolingian dynasties, especially that of Charlemagne, the first emperor of the Romans in the west since t ...
''De Villis'', dating to around 800, representing the royal will of
Charlemagne
Charlemagne ( , ) or Charles the Great ( la, Carolus Magnus; german: Karl der Große; 2 April 747 – 28 January 814), a member of the Carolingian dynasty, was King of the Franks from 768, King of the Lombards from 774, and the first ...
, mentions soap as being one of the products the stewards of royal estates are to tally. The lands of
Medieval Spain were a leading soapmaker by 800, and soapmaking began in the
Kingdom of England
The Kingdom of England (, ) was a sovereign state on the island of Great Britain from 12 July 927, when it emerged from various History of Anglo-Saxon England, Anglo-Saxon kingdoms, until 1 May 1707, when it united with Kingdom of Scotland, ...
about 1200. Soapmaking is mentioned both as "women's work" and as the produce of "good workmen" alongside other necessities, such as the produce of carpenters, blacksmiths, and bakers.
In Europe, soap in the 9th century was produced from animal fats and had an unpleasant smell. This changed when olive oil began to be used in soap formulas instead, after which much of Europe's soap production moved to the Mediterranean olive-growing regions.
Hard toilet soap was introduced to Europe by Arabs and gradually spread as a luxury item. It was often perfumed.
By the 15th century, the manufacture of soap in the
Christendom
Christendom historically refers to the Christian states, Christian-majority countries and the countries in which Christianity dominates, prevails,SeMerriam-Webster.com : dictionary, "Christendom"/ref> or is culturally or historically intertwine ...
had become virtually industrialized, with sources in
Antwerp,
Castile,
Marseille
Marseille ( , , ; also spelled in English as Marseilles; oc, Marselha ) is the prefecture of the French department of Bouches-du-Rhône and capital of the Provence-Alpes-Côte d'Azur region. Situated in the camargue region of southern Fra ...
,
Naples
Naples (; it, Napoli ; nap, Napule ), from grc, Νεάπολις, Neápolis, lit=new city. is the regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 909,048 within the city's adminis ...
and
Venice
Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 bridges. The isla ...
.
15th–18th centuries
In France, by the second half of the 15th century, the semi-industrialized professional manufacture of soap was concentrated in a few centers of
Provence
Provence (, , , , ; oc, Provença or ''Prouvènço'' , ) is a geographical region and historical province of southeastern France, which extends from the left bank of the lower Rhône to the west to the Italian border to the east; it is bor ...
—
Toulon
Toulon (, , ; oc, label= Provençal, Tolon , , ) is a city on the French Riviera and a large port on the Mediterranean coast, with a major naval base. Located in the Provence-Alpes-Côte d'Azur region, and the Provence province, Toulon is th ...
,
Hyères
Hyères (), Provençal Occitan: ''Ieras'' in classical norm, or ''Iero'' in Mistralian norm) is a commune in the Var department in the Provence-Alpes-Côte d'Azur region in southeastern France.
The old town lies from the sea clustered arou ...
, and
Marseille
Marseille ( , , ; also spelled in English as Marseilles; oc, Marselha ) is the prefecture of the French department of Bouches-du-Rhône and capital of the Provence-Alpes-Côte d'Azur region. Situated in the camargue region of southern Fra ...
—which supplied the rest of France. In Marseilles, by 1525, production was concentrated in at least two factories, and soap production at Marseille tended to eclipse the other Provençal centers. English manufacture tended to concentrate in London.
Finer soaps were later produced in Europe from the 16th century, using vegetable oils (such as
olive oil) as opposed to animal fats. Many of these soaps are still produced, both industrially and by small-scale artisans.
Castile soap is a popular example of the vegetable-only soaps derived from the oldest "white soap" of Italy. In 1634 Charles I granted the newly formed Society of Soapmakers a monopoly in soap production who produced certificates from ‘foure Countesses, and five Viscountesses, and divers other Ladies and Gentlewomen of great credite and quality, besides common Laundresses and others’, testifying that ‘the New White Soap washeth whiter and sweeter than the Old Soap’.
Industrially manufactured ''bar soaps'' became available in the late 18th century, as advertising campaigns in Europe and America promoted popular awareness of the relationship between cleanliness and health. In modern times, the use of soap has become commonplace in industrialized nations due to a better understanding of the role of
hygiene
Hygiene is a series of practices performed to preserve health.
According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refer ...
in reducing the population size of
pathogenic microorganisms.
File:Dobbins' medicated toilet soap, advertising, 1869.jpg, Advertising for Dobbins' medicated toilet soap
File:Palmolive soap 1922 advertisement ladies home journal.jpeg, A 1922 magazine advertisement for Palmolive Soap
File:Liquid antibacterial soap.jpg, Liquid soap
19th century
![langtry cartoon](https://upload.wikimedia.org/wikipedia/commons/1/1f/Langtry_cartoon.png)
Until the
Industrial Revolution
The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...
, soapmaking was conducted on a small scale and the product was rough. In 1780,
James Keir
James Keir FRS (20 September 1735 – 11 October 1820) was a Scottish chemist, geologist, industrialist, and inventor, and an important member of the Lunar Society of Birmingham.
Life and work
Keir was born in Stirlingshire, Scotland, in ...
established a chemical works at
Tipton
Tipton is an industrial town in the West Midlands in England with a population of around 38,777 at the 2011 UK Census. It is located northwest of Birmingham.
Tipton was once one of the most heavily industrialised towns in the Black Country, w ...
, for the manufacture of alkali from the sulfates of
potash
Potash () includes various mined and manufactured salts that contain potassium in water-soluble form. and soda, to which he afterwards added a soap manufactory. The method of extraction proceeded on a discovery of Keir's. In 1790,
Nicolas Leblanc
Nicolas Leblanc (December 6, 1742 – January 16, 1806) was a French chemist and surgeon who discovered how to manufacture soda ash from common salt.
Earlier days
Leblanc was born in Ivoy le Pré, Cher, France on 6 December 1742. His fathe ...
discovered how to make alkali from
common salt.
Andrew Pears
Andrew Pears was an English man, born around 1770, who invented transparent soap. He moved to London in 1789 from his home in Mevagissey, Cornwall, where he had trained as a barber.
He opened a barber's shop in the then-fashionable residential ...
started making a high-quality, transparent soap,
Pears soap
Pears transparent soap is a British brand of soap first produced and sold in 1807 by Andrew Pears, at a factory just off Oxford Street in London. It was the world's first mass-market translucent soap. Under the stewardship of advertising pionee ...
, in 1807 in London. His son-in-law,
Thomas J. Barratt, became the brand manager (the first of its kind) for Pears in 1865. In 1882, Barratt recruited English actress and socialite
Lillie Langtry
Emilie Charlotte, Lady de Bathe (née Le Breton, formerly Langtry; 13 October 1853 – 12 February 1929), known as Lillie (or Lily) Langtry and nicknamed "The Jersey Lily", was a British socialite, stage actress and producer.
Born on the isla ...
to become the poster-girl for Pears soap, making her the first celebrity to endorse a commercial product.
During the
Restoration era (February 1665 – August 1714) a soap tax was introduced in England, which meant that until the mid-1800s, soap was a luxury, used regularly only by the well-to-do. The soap manufacturing process was closely supervised by revenue officials who made sure that soapmakers' equipment was kept under lock and key when not being supervised. Moreover, soap could not be produced by small makers because of a law that stipulated that soap boilers must manufacture a minimum quantity of one imperial ton at each boiling, which placed the process beyond the reach of the average person. The soap trade was boosted and deregulated when the tax was repealed in 1853.
William Gossage
William Gossage (12 May 1799 – 9 April 1877) was a chemical manufacturer who established a soap making business in Widnes, Lancashire, England.
Early life
William Gossage was born in the village of Burgh-le-Marsh, Lincolnshire to Thomas and El ...
produced low-priced, good-quality soap from the 1850s.
Robert Spear Hudson
Robert Spear Hudson (6 December 1812 – 6 August 1884) was an English businessman who popularised dry soap powder. His company was very successful thanks to both an increasing demand for soap and his unprecedented levels of advertising. After ...
began manufacturing a soap powder in 1837, initially by grinding the soap with a
mortar and pestle
Mortar and pestle is a set of two simple tools used from the Stone Age to the present day to prepare ingredients or substances by crushing and grinding them into a fine paste or powder in the kitchen, laboratory, and pharmacy. The ''mortar'' ( ...
. American manufacturer
Benjamin T. Babbitt introduced marketing innovations that included the sale of bar soap and distribution of
product sample
A product sample is a sample of a consumer product that is given to the consumer free of cost so that they may try a product before committing to a purchase.
Free samples
A free sample or "freebie" is a portion of food or other product (for exam ...
s.
William Hesketh Lever
William Hesketh Lever, 1st Viscount Leverhulme , (, ; 19 September 1851 – 7 May 1925) was an English industrialist, philanthropist, and politician. Having been educated at a small private school until the age of nine, then at church schools ...
and his brother,
James
James is a common English language surname and given name:
*James (name), the typically masculine first name James
* James (surname), various people with the last name James
James or James City may also refer to:
People
* King James (disambiguati ...
, bought a small soap works in
Warrington
Warrington () is a town and unparished area in the borough of the same name in the ceremonial county of Cheshire, England, on the banks of the River Mersey. It is east of Liverpool, and west of Manchester. The population in 2019 was estimat ...
in 1886 and founded what is still one of the largest soap businesses, formerly called Lever Brothers and now called
Unilever
Unilever plc is a British multinational consumer goods company with headquarters in London, England. Unilever products include food, condiments, bottled water, baby food, soft drink, ice cream, instant coffee, cleaning agents, energy dri ...
. These soap businesses were among the first to employ large-scale
advertising
Advertising is the practice and techniques employed to bring attention to a product or service. Advertising aims to put a product or service in the spotlight in hopes of drawing it attention from consumers. It is typically used to promote a ...
campaigns.
Liquid soap
![Pexels-pixabay-433624](https://upload.wikimedia.org/wikipedia/commons/c/c2/Pexels-pixabay-433624.jpg)
Liquid soap was not invented until the nineteenth century; in 1865, William Sheppard patented a liquid version of soap. In 1898, B.J. Johnson developed a soap derived from palm and olive oils; his company, the
B.J. Johnson Soap Company, introduced "
Palmolive" brand soap that same year. This new brand of soap became popular rapidly, and to such a degree that B.J. Johnson Soap Company changed its name to
Palmolive.
In the early 1900s, other companies began to develop their own liquid soaps. Such products as
Pine-Sol and
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another.
Tide tables ...
appeared on the market, making the process of cleaning things other than skin, such as clothing, floors, and bathrooms, much easier.
Liquid soap also works better for more traditional or non-machine washing methods, such as using a
washboard.
Soap-making for hobbyists
![Soap and Detergent manufacturing process 03](https://upload.wikimedia.org/wikipedia/commons/4/46/Soap_and_Detergent_manufacturing_process_03.png)
A variety of methods are available for hobbyists to make soap. Most soapmakers use processes where the glycerol remains in the product, and the saponification continues for many days after the soap is poured into
molds. The glycerol is left during the hot process method, but at the high temperature employed, the reaction is practically completed in the kettle, before the soap is poured into molds. This simple and quick process is employed in small factories all over the world.
Handmade soap from the cold process also differs from industrially made soap in that an excess of fat or (Coconut Oil, Cazumbal Process) are used, beyond that needed to consume the
alkali (in a cold-pour process, this excess fat is called "superfatting"), and the glycerol left in acts as a moisturizing agent. However, the glycerine also makes the soap softer. The addition of glycerol and processing of this soap produces
glycerin soap. Superfatted soap is more skin-friendly than one without extra fat, although it can leave a "greasy" feel. Sometimes, an
emollient
A moisturizer, or emollient, is a cosmetic preparation used for protecting, moisturizing, and lubricating the skin. These functions are normally performed by sebum produced by healthy skin. The word "emollient" is derived from the Latin verb ''m ...
is added, such as
jojoba
Jojoba (; botanical name: ''Simmondsia chinensis'')also commonly called goat nut, deer nut, pignut, wild hazel, quinine nut, coffeeberry, and gray box bushis native to the Southwestern United States. ''Simmondsia chinensis'' is the sole specie ...
oil or
shea butter.
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class o ...
or
pumice
Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular v ...
may be added to produce a
scouring soap. The scouring agents serve to remove dead cells from the skin surface being cleaned. This process is called
exfoliation.
To make
antibacterial
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...
soap, compounds such as
triclosan
Triclosan (sometimes abbreviated as TCS) is an antibacterial and antifungal agent present in some consumer products, including toothpaste, soaps, detergents, toys, and surgical cleaning treatments. It is similar in its uses and mechanism of ac ...
or
triclocarban
Triclocarban (sometimes abbreviated as TCC) is an antibacterial chemical once common in, but now phased out of, personal care products like soaps and lotions. It was originally developed for the medical field. Although the mode of action is unkn ...
can be added. There is some concern that use of antibacterial soaps and other products might encourage
antimicrobial resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. P ...
in microorganisms.
Gallery
File:African Black Soap.jpg, Dudu-Osun – a popular type of African black soap
File:Azul e Branco.JPG, Azul e branco soap
Azul e branco (''blue and white''), also known as sabão Offenbach (''Offenbach soap'') or sabão macaco (''monkey soap''), is a type of soap used in Portugal. It is comparable to household soap, but has a rugged texture, bulky shape, lack of odor ...
– a bar of blue-white soap
File:Soap P1140887.jpg, Handmade soaps sold at a shop in Hyères
Hyères (), Provençal Occitan: ''Ieras'' in classical norm, or ''Iero'' in Mistralian norm) is a commune in the Var department in the Provence-Alpes-Côte d'Azur region in southeastern France.
The old town lies from the sea clustered arou ...
, France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...
File:Savon de Marseille.jpg, Traditional Marseille soap
Marseille soap or ''Savon de Marseille'' () is a traditional hard soap made from vegetable oils that has been produced around Marseille, France, for about 600 years. The first documented soapmaker was recorded there in about 1370. By 1688, Loui ...
File:Soap Shop, Tübingen (2019).jpg, Modern soap shop in Tübingen
Tübingen (, , Swabian: ''Dibenga'') is a traditional university city in central Baden-Württemberg, Germany. It is situated south of the state capital, Stuttgart, and developed on both sides of the Neckar and Ammer rivers. about one in three ...
(2019)
File:Pouring lye into water to make soap.jpg, The lye
A lye is a metal hydroxide traditionally obtained by leaching wood ashes, or a strong alkali which is highly soluble in water producing caustic basic solutions. "Lye" most commonly refers to sodium hydroxide (NaOH), but historically has been u ...
is dissolved in water.
File:Wheel Bearing Grease.jpg, Greases for automotive applications contain soaps
File:Pexels-pixabay-206299.jpg, Soap on a platter
See also
Personal use soap
*
African black soap, popular in West Africa
*
Aleppo soap, popular in Syria
*
Castile soap, popular in Spain
*
Lava (soap)
Lava is a heavy-duty hand cleaner in soap bar form manufactured by the WD-40 Company. Unlike typical soap bars, Lava contains ground pumice, which gave the soap its name. The soap and pumice combination is intended to scour tar, engine grease, p ...
, cleaning hands from industrial grease and dirt
*
Marseille soap
Marseille soap or ''Savon de Marseille'' () is a traditional hard soap made from vegetable oils that has been produced around Marseille, France, for about 600 years. The first documented soapmaker was recorded there in about 1370. By 1688, Loui ...
, popular in France
*
Nabulsi soap
Nabulsi soap ( ar, صابون نابلسي, ''ṣābūn Nābulsi'') is a type of castile soap produced only in Nablus in the West Bank, Palestine. Its chief ingredients are virgin olive oil (the main agricultural product of the region), water, an ...
, popular in the West Bank
*
Saltwater soap
Saltwater soap, also called sailors' soap, is a potassium-based soap for use with seawater. Inexpensive common commercial soap will not lather or dissolve in seawater due to high levels of sodium chloride in the water. Similarly, common soap does ...
, used to wash in seawater
*
Shaving soap, used for shaving
*
Vegan soap
Vegan soaps (or vegetable soaps) are soaps made from fats or oils of vegetable origin rather than from saponified animal fats. The Vegan Society's definition of veganism encourages consumers to avoid all products containing ingredients derived fr ...
, made without use of animal byproducts
Soap-related
*
Antibiotic misuse
Antibiotic misuse, sometimes called antibiotic abuse or antibiotic overuse, refers to the misuse or overuse of antibiotics, with potentially serious effects on health. It is a contributing factor to the development of antibiotic resistance, includ ...
*
Dishwashing soap
*
Foam
Foams are materials formed by trapping pockets of gas in a liquid or solid.
A bath sponge and the head on a glass of beer are examples of foams. In most foams, the volume of gas is large, with thin films of liquid or solid separating the ...
*
List of cleaning products
This is a list of cleaning products and agents. Cleaning agents are substances (usually liquids, powders, sprays, or granules) used to remove dirt, including dust, stains, bad smells, and clutter on surfaces. Purposes of cleaning agents include hea ...
*
Hand washing
Hand washing (or handwashing), also known as hand hygiene, is the act of cleaning one's hands with soap or handwash and water to remove viruses/bacteria/microorganisms, dirt, grease, or other harmful and unwanted substances stuck to the hands ...
*
Palm oil
*
Soap bubble
*
Soap dish
A soap dish is a shallow, open container or platform where a bar of soap may be placed to dry after use. Soap dishes are usually located in or near a sink, shower, or bathtub. Most soap dishes are made from waterproof materials such as plastic, ...
*
Soap dispenser
A soap dispenser (in Europe mostly known as a soap squirter) is a device that, when manipulated or triggered appropriately, dispenses soap (usually in small, single-use quantities). It can be manually operated using a handle or can be automatic. ...
*
Soap plant
*
Soap substitute
Traditionally, soap has been made from animal or plant derived fats and has been used by humans for cleaning purposes for several thousand years. Soap is not harmful to human health but, like any natural or unnatural surfactant, it does have the p ...
*
Soapwort
''Saponaria'' is a genus of flowering plants in the family Caryophyllaceae, native to Asia and Europe, and are commonly known as soapworts. They are herbaceous perennials and annuals, some with woody bases. The flowers are abundant, five-petall ...
*
Shampoo
Shampoo () is a hair care product, typically in the form of a Viscosity, viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product ...
*
Shower gel
Shower gel (also shower cream or body wash) is a specialized liquid product used for cleaning the body during showers. Not to be confused with liquid soaps, shower gels, in fact, do not contain saponified oil. Instead, it uses synthetic detergen ...
*
Toothpaste
Toothpaste is a paste or gel dentifrice used with a toothbrush to clean and maintain the aesthetics and health of teeth. Toothpaste is used to promote oral hygiene: it is an abrasive that aids in removing dental plaque and food from the teeth, ...
*
Soap made from human corpses
During the 20th century, there were various alleged instances of soap being made from human body fat. During World War I the British press claimed that the Germans operated a corpse factory in which they made glycerine and soap from the bodies of ...
References
Further reading
* Free ebook at
Google Books
Google Books (previously known as Google Book Search, Google Print, and by its code-name Project Ocean) is a service from Google Inc. that searches the full text of books and magazines that Google has scanned, converted to text using optical ...
.
* Donkor, Peter (1986).
Small-Scale Soapmaking: A Handbook'. Ebook online at
SlideShare
SlideShare is an American hosting service, now owned by Scribd, for professional content including presentations, infographics, documents, and videos. Users can upload files privately or publicly in PowerPoint, Word, PDF, or OpenDocument format. ...
. .
* Dunn, Kevin M. (2010). ''Scientific Soapmaking: The Chemistry of Cold Process''. Clavicula Press. .
* Garzena, Patrizia, and Marina Tadiello (2004). ''Soap Naturally: Ingredients, methods and recipes for natural handmade soap''
Online information and Table of Contents /
* Garzena, Patrizia, and Marina Tadiello (2013). ''The Natural Soapmaking Handbook''
Online information and Table of Contents /
* Mohr, Merilyn (1979). ''The Art of Soap Making''. A Harrowsmith Contemporary Primer. Firefly Books. .
* Spencer, Bob; Practical Action (2005).
SOAPMAKING'. Ebook online.
*
* Thomssen, E. G., Ph.D. (1922).
Soap-Making Manual'. Free ebook at
Project Gutenberg
Project Gutenberg (PG) is a volunteer effort to digitize and archive cultural works, as well as to "encourage the creation and distribution of eBooks."
It was founded in 1971 by American writer Michael S. Hart and is the oldest digital libr ...
.
External links
*
{{Authority control
Anionic surfactants
Cleaning products
Salts
Skin care
Bathing