Soap Facts is an alphabetical list of topics and ingredients to help you understand how our soap is made, some of the ingredients we use and what is not in our soap. Green Hill Soaps uses the highest quality ingredients and we support sustainable practices whenever possible. If there is an ingredient that you would like to learn more about, we recommend Wikipedia and or doing a Google search, which can provide endless amounts of information on specific ingredients that you are researching. Much of the information on Soap Facts was summarized from Wikipedia and or from product fact sheets provided by suppliers. We hope you find this page a great place to start.
Please note that nothing on this Soap Facts page or on our site is a representation of medicinal efficacy or medical advice of any kind. If you have a medical issue or questions, we advise you to speak to your doctor about your condition.
Avocado oil is a heavy, green, rich, moisturizing oil. It’s often used in soap recipes for people with sensitive skin. Avocado oil contains Vitamins A, B1, B2, D, E, and Beta carotene. It is classified as a monosaturated oil and is best suited for dry skin conditions in topical applications and is used with other oils to make high quality soap.
It is a distillate that was originally made in Saint Thomas from rum and the leaves and/or berries of the West Indian bay tree. Some distillers include other ingredients such as citrus and spice oils, the most common being lime oil, oil of cloves and cinnamon. It was first made fashionable in New York and other American cities before it was available in Europe. Bay Rum is different from Bay Laurel, the “bay leaves” in common culinary use are from a completely unrelated species.
Callendula, the dried petals of the Marigold flower, was first used by the Romans to treat scorpion bites, and old herbal doctors recommended regularly applying Callendula as a way to prevent gangrene. It is said to support the connective tissues of the skin, and is thought to be beneficial for all types of skin irritations and injuries such as burns, rashes, cuts and varicose veins. Due to its natural content on iodine, it is thought to be one of the best antiseptics available.
Castile soap is a name used in English-speaking countries for olive oil based soap made in a style similar to that originating in the Castile region of Spain. The origins of Castile Soap can be traced back to The Levant where Aleppo soap makers have been making an olive and laurel oil based hard soap for more than a millennia. It is commonly believed that the Crusaders brought Aleppo Soap back to Europe with them in the 11th century. Following the Crusades. The first European soap-making factories were created in the 12th century in Spain (Alicante, Malaga, Carthagene and Castile) and in Italy (Naples, Savone, Genoa, Bologna and Venice) and then, in the middle of the 15th century, in Marseille France, giving birth to Marseille soap. However, early soap makers in Europe did not have easy access to laurel oil and therefore dropped it from their formulations thereby creating an olive oil soap now known as Castile soap.
Castor oil contains Ricinoleic Acid, which delivers anti-inflammatory benefits to the skin. It is also used as a treatment for minor cuts, burns, abrasions, and sunburn. Many find Castor oil to be beneficial for skin disorders such as acne and eczema. Castor oil is a natural emollient, which stimulates the production of collagen and elastin that hydrates and moisturizes the skin. Some people use Castor oil to treat wrinkles, repairing and rejuvenating the skin to make it look flawless and smoother.
Cocoa Butter is a luscious moisturizing fat that has been used for centuries in Africa for its moisturizing and healing properties. It has been used to protect and condition skin which has been damaged by the sun and wind. Cocoa Butter contains natural antioxidants. It is naturally rich in Vitamin E as well as a number of other vitamins and minerals. Vitamin E helps to soothe, hydrate, and balance the skin. Cocoa Butter is has a melting point at human body temperature and is edible and nutritious.
Coconut oil is thought to have anti-fungal, antiviral, and antibacterial properties, and contains Lauric Acid which is unique and wonderful for the skin. Virgin Coconut Oil is extracted from freshly harvested coconuts using a wet milling process that uses neither chemicals nor high heat. The result is a clear oil that retains the distinct scent of coconuts. Virgin Coconut Oil is a great ingredient for lotions and hair treatments as well as soaps. In addition, it is naturally full of antioxidants.
Dead Sea Mud
Mud from the Dead Sea has been legendary for centuries. The Dead Sea is the most saline body of water in the world with far greater concentrations of minerals than any ocean (a concentration of 32% minerals compared to other seas, holding approximately 3%). Mud from the Dead Sea has a high salt and mineral content, all of which are essential for the body. The mud infuses the skin with minerals leaving it clean, refreshed and hydrated. Dead Sea mud has the dual purpose of exfoliation and being as a natural cleanser. It not only removes toxins and impurities from the skin, but also tightens and tones the skin, improves blood circulation, hydrates the skin and aids in skin regeneration.
Essential oils are believed to have therapeutic value and countless varied compounds that facilitate healing and renewal for the skin and body. Pure food grade essential oils have been used for a millennium in many alternative healing traditions. An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils or aetherolea, or simply as the “oil of” the plant from which they were extracted, such as oil of clove. An oil is “essential” in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not form a distinctive category for any medical, pharmacological, or culinary purpose. Essential oils are generally extracted by distillation. They are used in perfumes, cosmetics, soaps and other products, for flavoring food and drink, and for adding scents to incense and household cleaning products. Various essential oils have been used medicinally at different periods in history. As the use of essential oils has declined in evidence-based medicine, one must consult older textbooks for much information on their use.The techniques and methods first used to produce essential oils was first mentioned by Ibn al-Baitar (1188–1248), an Andalusian physician, pharmacist and chemist. Medical applications proposed by those who sell medicinal oils range from skin treatments to remedies for cancer, and often are based solely on historical accounts of use of essential oils for these purposes. Claims for the efficacy of medical treatments and treatment of cancers in particular, are now subject to regulation in most countries.
French Green Clay
French Green Clay comes from the sedimentation of Silico-aluminum, its coloring the result of the oxides contained in these rocks. Its unique composition includes Iron, Silica, Aluminum, Magnesium, Calcium, Titanium, Sodium and Potassium. French Green Clay absorbs and removes impurities from the skin, stimulating blood flow to create healthy and glowing skin. When prepared as a mask, the clay dries on the skin causing pores to tighten and the skin to feel firm, toned and refreshed. French Green Clay can be used in poultices to treat arthritis, sore muscles, and sprains; in ready-to-use pastes for application to cuts, bruises, insect bites, stings, and minor burns; and mineral baths for stress relief. It is suitable for all skin types.
French Pink Clay
French Pink Clay is a combination of red and white clays. It is considered to be the mildest of all the clays and works well for normal, sensitive and mature skin types. Its unique composition includes Kaolinite, Iron, Illite, Montmorillonite and Calcite. French Pink Clay can be used to cleanse and detoxify the skin, remove dead skin cells and create and overall refreshed appearance. It can also be used to treat acne and other skin ailments; poor blood and/or lymph circulation and sun damaged skin. It is most widely used in cosmetic manufacturing.
Glycerine (formally glycerol or glycerin) is a simple polyol compound. It is a colorless, odorless, viscous liquid that is widely used in pharmaceutical formulations. Glycerine has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature. Chemically speaking, glycerine forms the backbone of triglycerides, and is chiefly produced by saponification of fats as a byproduct of soap-making. Glycerine is sweet-tasting and of low toxicity.
Glycerrine is used in medical and pharmaceutical and personal care product as a means of improving smoothness, providing lubrication and as a humectant. It is found in allergen immunotherapies, cough syrups, elixirs and expectorants, toothpaste, mouthwashes, skin care products, shaving cream, hair care products, soaps and water-based personal lubricants. Glycerol is a component of cold process soaps and glycerin soap. This kind of soap is used by people with sensitive, easily irritated skin because glycerine prevents skin dryness with its moisturizing properties. It draws moisture up through skin layers and slows or prevents excessive drying and evaporation. Topical pure or nearly pure glycerol is an effective treatment for psoriasis, burns, bites, cuts, rashes, bedsores, and calluses.
Himalayan Pink Salt
Also Known as Himalayan Rock Salt , this salt is hand-mined and harvested from ancient salt beds, deep under the Himalayan Mountains. Rich in over 80 minerals and trace elements, some of the most notable being calcium, magnesium, potassium, copper and iron, this salt is considered to be the purest form of salt available. For therapeutic purposes, the Himalayan Rock Salt can be used in baths to relax the body, stimulate circulation, sooth sore muscles, and remove toxins. It is reputed to assist with relief from arthritis, skin rashes, wounds, and flu and fever symptoms.
Historically, honey has been used by humans to treat a variety of ailments through topical application, but only recently have the antiseptic and antibacterial properties of honey been chemically explained. As an antimicrobial agent honey may have the potential for treating a variety of ailments. When honey is used topically (as, for example, a wound dressing), hydrogen peroxide is produced by dilution of the honey with body fluids. As a result, hydrogen peroxide is released slowly and acts as an antiseptic. The relatively acidic pH level of honey prevents the growth of many bacteria. Some studies suggest the topical use of honey may reduce odors, swelling, and scarring when used to treat wounds. Honey has also been used for centuries as a treatment for sore throats and coughs and, according to recent research, may be an effective soothing agent for coughs. Honey also tastes great and has a wonderful gently fragrance.
Humectants are known as hygroscopic substances. Hygroscopic substances absorb water from the air. Humectants are found in many cosmetic products where moisturization is desired, including treatments such as moisturizing hair conditioners and body lotions. Humectants increase the solubility of an active ingredient, to elevate its skin penetration and increase its activity time. Humectants also elevate the hydration of the skin.
Also known as White Cosmetic Clay, China Clay, White Clay, Chalk, and White Dirt, Kaolin has a variety of uses. Soap makers often use it in shaving and oily skin soaps as it adds slip while being safe and generally non-sensitizing. This soft and gentle clay can also be mixed with water to form facial masks that help to remove oil from the skin keeping the nose from looking shiny. Other applications include in the formulation of natural deodorants, poultices and scrubs.
Lavender, the plant is grown mainly for the production of essential oil of lavender. Lavender oil, which has long been used in the production of perfume, bath products, and aromatherapy. The scent has a calming effect which may aid in relaxation and the reduction of anxiety and stress. Lavender is also thought to have antiseptic and anti-inflammatory properties. It may also help to relieve pain from tension headache when breathed in as vapor or diluted and rubbed on the skin. When added to a vaporizer, lavender oil may aid in the treatment of cough and respiratory infection. Lavender oil may also be used as a mosquito repellent when worn as perfume or when added to lotions or hair products. It also relieves inflammation, cleanses the skin and reduces oiliness in hair.
Lye is an alkaline substance, commonly sodium hydroxide (NaOH, also known as ‘caustic soda’) or historically potassium hydroxide (KOH, from hydrated potash). Previously, lye was among the many different alkalis leached from hardwood ashes.
Both sodium hydroxide (lye) and potassium hydroxide (potash) are used in soap making. Sodium hydroxide is often used to make solid soap while potassium hydroxide is used to make liquid soap. Soaps made of potassium hydroxide are softer and can more easily be dissolved in water than sodium hydroxide soaps.
When soap making, sodium hydroxide cannot be substituted with potassium hydroxide and vice versa because different soap making recipes will have different quantity requirements for these two chemicals. In addition, the quantities required for soap saponification differ when using lye and hydrated potash.
Olive oil has been known for generations not only for its healing qualities but also as a natural, deep penetration moisturizer, regenerating skin cells and softening the tissue. Olive oil has a great conditioning effect in body care recipes and can be used in almost all applications because of its stable nature. High in polyphenols which are powerful antioxidants and nutrient rich, it has been used to help soothe burns and scrapes.
Oxides, Ultramarines and Micas
Mineral Powder Pigments such as oxides , ultramarines and micas are pigments mined from the earth and then processed and refined to remove any harmful metals. Mica is a fine mineral powder than can be used to reflect light and create a pearlescent effect on skin. These products are cosmetic grade and approved for use in soap, mineral cosmetics and cosmetic bases. They are used in our soaps because they are natural color additives which are insoluble and will remain suspended within the product and will not dissolve; they will not bleed or fade.
Palm Oil is most commonly used in handmade soap to increase lather and hardness. It may also be used in a multitude of other cosmetic and body care products for its moisturizing properties. Palm oil can be found in lotions, cremes, balms, body butters and stick formulations where a thicker product is desired. Palm oil is used, in our soaps, in the place of animal tallow, or sodium tallowate (see below). Animal tallow is a by-product of the slaughtering process and is used in commercial “soaps” for hardness and lather because it is very inexpensive.
Rhassoul Clay is an exceptional clay with multipurpose assets. It is mined in the fertile Atlas Mountains of Morocco and has been used for over 12 centuries by population in North Africa, Southern Europe and Middle East. Rhassoul Clay’s most impressive properties in skin improvement are its capacity of absorption due to its high level of ions exchange. Studies have shown that it is reputed to reduce dryness and flakiness, improve skin clarity and elasticity. It is rich in magnesium, Silica, potassium and calcium. It is used in many professional applications in spas and it aids in rejuvenation, detoxification and toning of the skin. It can be used in soaps, shampoos, facial hair and body masks and skin conditioners.
Saponification is a chemical process that produces soap, usually from mixing fats, oils and lye.
Shea Butter is extracted from the nuts of the Kotschy tree which grows in Central Africa. Shea butter is an extremely therapeutic emollient with high levels of vitamin A and E. These high antimicrobial and moisturizing properties heal and renew the skin as well as the entire body.
Seaweed Powder is made from a brown seaweed commonly known as kelp . Seaweed Powder is a rich source of vitamins including vitamins B12 (not found in land plants), vitamin E, amino acids, minerals, trace elements, and other nutrients. Seaweed powder makes for an effective cleansing and exfoliation agent. When applied to the skin, Seaweed treatments act as a powerful detoxifier that draws out toxins and impurities while adding beneficial nutrients. It helps to stimulate the body’s metabolism and circulation which gives skin a healthy, revitalize and glowing appearance. Seaweed contains fatty acids to combat skin irritation and inflammation; and may assist with skin ailments such as acne, psoriasis and eczema. Seaweed Powder is suitable for all skin types.
One word of caution: persons with an allergy to iodine should avoid using this product.
Silk Powder, Silk Peptide, and Silk Amino Acids all contain 18 different amino acids, all come from the cocoon of the silk worm, and all have a chemical composition that is very close to that of human skin and hair making them a wonderful source of nourishment and maintenance.
Soaps are mainly used as surfactants for washing, bathing, and cleaning, but they are also used in textile spinning and are important components of lubricants. When used for cleaning, soap serves as a surfactant in conjunction with water. Surfactants are compounds that lower the surface tension of a liquid, the interfacial tension between two liquids, or that between a liquid and a solid. The cleaning action of soap is attributed to the action of micelles, tiny molecular spheres coated on the outside with water-loving groups, encasing a fat-loving pocket that can surround the grease particles, causing them to disperse in water. In other words, whereas normally oil and water do not mix, the addition of soap allows oils to disperse in water and be rinsed away.
Soaps for cleansing are obtained by treating vegetable or animal oils and fats with a strongly alkaline solution. The alkaline solution, often called lye, brings about a chemical reaction known as saponification. In saponification, the fats are first hydrolyzed into free fatty acids, which then combine with the alkali to form crude soap. Glycerol, often called glycerine, is liberated and is either left in or washed out and recovered as a useful by-product according to the process employed.
The type of alkali determines the kind of soap produced. Sodium soaps, prepared from sodium hydroxide (lye), are firm, whereas potassium soaps (potash), derived from potassium hydroxide, are softer or often liquid. Soaps are derivatives of fatty acids. Traditionally they have been made from triglycerides (oils and fats). Triglyceride is the chemical name for the triesters of fatty acids and glycerin. Tallow (rendered beef fat), is the most available triglyceride from animals. Once saponified, it is called sodium tallowate. Typical vegetable oils used in soap making are palm oil, coconut oil, olive oil, and laurel oil. Each species offers quite different fatty acid content and, hence, results in soaps of distinct feel. The seed oils give softer but milder soaps. Soap made from pure olive oil is sometimes called Castile soap or Marseille soap and is reputed for being extra-mild. The term “Castile” is also sometimes applied to soaps from a mixture of oils, but a high percentage of olive oil.
The earliest recorded evidence of the production of soap-like materials dates back to around 2800 BC in Ancient Babylon. In the reign of Nabonidus (556–539 BCE) a recipe for soap consisted of uhulu [ashes], cypress [oil] and sesame [seed oil] “for washing the stones for the servant girls”. A formula for soap consisting of water, alkali, and cassia oil was written on a Babylonian clay tablet around 2200 BC. The Ebers papyrus (Egypt, 1550 BC) indicates that ancient Egyptians bathed regularly and combined animal and vegetable oils with alkaline salts to create a soap-like substance. The word sapo, Latin for soap, first appears in Pliny the Elder’s Historia Naturalis, which discusses the manufacture of soap from tallow and ashes, but he only mentions for its use as a pomade for hair; he also mentions, rather disapprovingly, that the men of Gaul and Germans were more likely to use it than their female counterparts. Aretaeus of Cappadocia, writing in the first century AD, observes that among “Celts, which are men called Gauls, those alkaline substances that are made into balls, called soap”. Zosimos of Panopolis, ca. 300 AD, describes soap and soapmaking. Galen,a prominent Roman (of Greek ethnicity) physician, surgeon and philosopher and arguably the most accomplished of all medical researchers of antiquity, describes soap-making using lye and prescribes washing to carry away impurities from the body and clothes. According to Galen, the best soaps were German, and soaps from Gaul were second best.
Solid soap was virtually unknown in northern Europe until the thirteenth century when it started being imported from Islamic Spain and North Africa. By that time the manufacture of soap in the Islamic world had become virtually industrialized, with sources in Fes, Damascus, and Aleppo. The Carolingian capitulary De Villis, dating to around 800, representing the royal will of Charlemagne, mentions soap as being one of the products the stewards of royal estates are to tally. Soap-making 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. A 12th century Islamic document has the world’s first extant description of the process of soap production. Mentioning the key ingredient, alkali, which later becomes crucial to modern chemistry, derived from the Arabic word “al-qaly” or “ashes”. Soap-makers in Naples were members of a guild in the late sixth century, and in the 8th century, soap-making was well-known in Italy and Spain. 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 (Toulon, Hyères, and Marseille) 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 by the oldest “white soap” of Italy.
In modern times, the use of soap has become universal in industrialized nations due to a better understanding of the role of hygiene in reducing the population size of pathogenic microorganisms. Industrially manufactured bar soaps first became available in the late eighteenth century, as advertising campaigns in Europe and the United States promoted popular awareness of the relationship between cleanliness and health.
Soap Making Process
There are two basic processes for making soap , the continuous process and the batch process. The industrial production of soap involves the continuous processes. This process is based on the continuous addition of fat and removal of product. Smaller-scale production uses the batch processes. The batch process has three variations: the cold-process, where the saponification reaction takes place substantially at room temperature, the semi-boiled or hot-process, in which the reaction takes place at near-boiling point, and the fully boiled process, wherein the reactants are boiled at least once and the glycerine is removed.
The cold-process and hot-process (semi-boiled) are the simplest and typically used by small artisan soap makers. In the case of cold-process soaps, the glycerine remains in the soap and the saponification reaction continues for many days after the soap is poured into molds. The glycerine is left during the hot-process method as well, but at the high temperature employed saponification is practically completed in the kettle, before the soap is poured into molds. This process is simple and quick and is the one employed in small factories all over the world.
Handmade soap from the cold-process also differs from industrially made soap in that the amount of oil is used is a bit more than necessary to consume the alkali, and the glycerine left in acts as a moisturizing agent. In a cold-pour process this excess oil is referred to as “superfatting”. Superfatted soap is more skin-friendly than one without extra fat.
Even in the cold-soapmaking process, some heat is usually required. This is to ensure complete melting of the “butters” being used. The batch may also be kept warm for some time after mixing to ensure that the alkali (hydroxide) is completely used up. This soap is safe to use after approximately 12–48 hours but is not at its peak quality for use for several weeks.
Hot-processed soaps are created by adding heat to the saponification reaction. This speeds the reaction. Unlike cold-processed soap, in hot-process soaping the oils are completely saponified by the end of the handling period, whereas with cold pour soap the bulk of the saponification happens after the oils and lye solution emulsification is poured into molds.
In the fully boiled process, the mix is actually boiled, and, after saponification has occurred, the “neat soap” is precipitated from the solution by adding common salt, and the excess liquid drained off. This excess liquid carries away much of the impurities and color compounds in the fat, to leave whiter soap, and with practically all the glycerine removed. The hot, soft soap is then pumped into a mold. The spent hydroxide solution is processed for recovery of glycerine.
Sodium Lauryl Sulfate
At Green Hill Soap, we do not use Sodium Lauryl Sulfate in any of our soaps. If you are not familiar with this chemical, widely used in detergents, shampoos, hand detergents, and “beauty bars”, please keep reading.
Sodium Dodecyl Sulfate (SDS or NaDS), sodium laurilsulfate or sodium lauryl sulfate (SLS) is an organic compound used in many cleaning and hygiene products. SDS/SLS is synthesized by treating lauryl alcohol with sulfur trioxide gas, or oleum, or chlorosulfuric acid to produce hydrogen lauryl sulfate. The industrially practiced method typically uses sulfur trioxide gas. The resulting product is then neutralized through the addition of sodium hydroxide or sodium carbonate. Lauryl alcohol is in turn usually derived from either coconut or palm kernel oil by hydrolysis, which liberates their fatty acids, followed by hydrogenation.
SDS/SLS is a highly effective surfactant and is used in any task requiring the removal of oily stains and residues. For example, it is found in higher concentrations with industrial products including engine degreasers, floor cleaners, and car wash soaps. It is found in toothpaste, shampoo, shaving foam, and bubble bath formulations in part for its thickening effect and its ability to create a lather, as well as its ability to remove oils from hair and skin.
According to Wikipedia, SDS/SLS has been shown to irritate the skin of the face with prolonged and constant exposure (more than an hour) in young adults. SDS/SLS may worsen skin problems in individuals with chronic skin hypersensitivity, with some people being affected more than others. In animal studies SDS/SLS appears to cause skin and eye irritation. A preliminary study suggested SDS/SLS in toothpaste caused the recurrence of canker sores.
Sodium Laureth Sulfate
Sodium laureth sulfate, or sodium lauryl ether sulfate (SLES), is a detergent and surfactant found in many personal care products (soaps, shampoos, toothpaste etc.). SLES is an inexpensive and very effective foaming agent. SLES, SLS and ALS are surfactants that are used in many cosmetic products for their cleansing and emulsifying properties. They behave similarly to soap, but are not soap.
While the FDA considers SLES safe at the concentrations used in cosmetic products, it is an irritant similar to other detergents , with the irritation increasing with concentration. SLES has been shown to produce eye or skin irritation in experimental animals and in some human test subjects. The related surfactant SLS (see above) is a known irritant , and research suggests that SLES can also cause irritation after extended exposure in some people. This issue has been known for some time.
At Green Hill Soap, we do not use animal tallow (Sodium Tallowate) in any of our soaps. Tallow is a rendered form of beef or mutton fat, processed from suet. It is solid at room temperature. Unlike suet, tallow can be stored for extended periods without the need for refrigeration to prevent rotting or spoilage, provided it is kept in an airtight container to prevent oxidation. 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, including its melting point. It is common for commercial tallow to contain fat derived from other animals, such as lard from pigs, or even from plant sources. When tallow is saponified in the chemical process of making soap, it becomes sodium tallowate, commonly used in most commercially produced synthetic detergents (see below) and “beauty bars”.
Sunflower Oil is wealthy in Oleic acids with high amounts of Vitamins A, D, and E, also has beneficial amounts of lecithin, and unsaturated fatty acids. Deeply nourishing and conditioning for the skin and it is highly recommended for recipes designed to treat dry, weathered, aged, and damaged skin. High in Linolenic acid.
Synthetic detergents (“Syn Dets”) are not soap, they are detergents . Syn Dets operate by similar mechanisms to soap. A detergent is a surfactant or a mixture of surfactants with “cleaning properties in dilute solutions.”In common usage, “detergent” refers to alkylbenzenesulfonates, a family of compounds that are “similar” to soap but are more soluble in hard water.