Lavandula Angustifolia (Lavender) Oil has been reported as beneficial for the treatment of burns, wounds, acne, insect bites, wound healing, and painful bruises. Other references recommend the oil for the treatment of fatigue, tired feet, rheumatism, sores, varicose veins and ulcers. The essential oil has been used for the improvement of sleep, by placing a few drops of the oil onto the pillow. The oil has also been used to calm a tense headache and may, in some cases, be useful in cases of migraine.

Lavender oil applied to human and animal skin produced little or no irritation, but it has caused sensitization, photosensitization and pigmentation in humans. In laboratory animals it was of low acute oral and dermal toxicity and low to moderate injection toxicity. Its principal effect following administration by oral, injection or inhalation routes to rodents, was sedation. It was rapidly absorbed through intact human skin.

CAS: 8000-28-0

Function: Fragrance ingredient/tonic/ refreshing/ cleansing/ deodorant/ masking.

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Ginseng is an excellent tonic, though it cannot be claimed to cure any specific ailment. Ginseng is used as a general tonic to treat tiredness, overexertion, neurasthenia, hypotension, general and nervous weakness, particularly in old age; mild depression.

Panax is derived from the Greek word panakos, “a panacea,” in reference to the miraculous virtues ascribed to it by the Chinese who consider it a Sovereign remedy in almost all diseases. It was formerly supposed to be confined to Chinese Tartary, but now is known to also be a native of North America, from when Sarrasin transmitted specimens to Paris in 1704.

CAS: 84650-12-4

Function: Emollient/ hair conditioning/ skin protecting/ tonic.

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Curcumin is extracted from the dried root of the turmeric rhizome Curcuma longa. The process of extraction requires the raw material to be ground into powder, and washed with a suitable solvent that selectively extracts coloring matter. This process after distillation of the solvent yields an oleoresin with coloring matter content in the region of 25–35% along with volatile oils and other resinous extractives. The oleoresin so obtained is subjected to further washes using selective solvents that can extract the curcumin pigment from the oleoresin. This process yields a powdered, purified food color, known as curcumin powder, with more than 90% coloring matter content and very little volatile oil and other dry matter of natural origin. The characteristic yellow color of turmeric is due to the curcuminoids, first isolated by Vogel in 1842.

Curcumin provides a water-soluble orange-yellow color. The rhizome of Curcuma longa has been used as a medicine, spice and coloring agent for thousands of years. The Negritoes of the Philippines utilize the fresh rhizome to treat recent wounds, bumps, bruises and leech bites. Mixed with gingelly oil (a locally produced oil), it is applied to the body to prevent further skin eruptions. Among the dark races of India, turmeric has been used since time immemorial to treat skin problems. Both the Ayurvedic and the Unani practitioners have used a paste of powdered turmeric or its fresh juice made into a paste or a decoction of the whole plant as a local application in the treatment of leprosy and cobra bites. It is especially useful for indolent ulcers on the surface of the skin and gangrene in the flesh. A paste made from the powdered rhizomes along with caustic lime forms a soothing remedy for inflamed joints. Turmeric is also used as an external application of “rouge” and is used by some women in India to suppress the unwelcome growth of facial hairs and upper lip moustaches.  In Northern India, the rhizome is used by many natives for treating cuts, burns and scalds.  The natives of Samoa use powdered rhizome to sprinkle on newborn infants to help heal a recently cut umbilical cord, to prevent nappy rash from occurring, and to keep the skin continually soft and resilient. The powder is also used as a paste or poultice to treat skin ulcers and to help heal extensive skin eruptions. In parts of Africa, turmeric has been successfully tested for healing rashes due to allergies and psoriasis inflammation, and itching accompanying arthritis.

It is a natural extract obtained by solvent extraction from the dried rhizomes of turmeric (used in Indian cuisine as a flavoring agent). Curcumin may be used to compensate for fading of natural coloring in pre-packed foods. Recognized as an anticarcinogenic agent during laboratory tests. It is widely used in traditional Indian medicine to cure biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism and sinusitis. Turmeric paste in slaked lime is a popular home remedy for the treatment of inflammation and wounds. Curcumin has antioxidant, anti-inflammatory, antiviral and antifungal actions. Studies have shown that curcumin is not toxic to humans. Curcumin exerts anti-inflammatory activity by inhibition of a number of different molecules that play an important role in inflammation.

CAS: 458-37-7

Function: Antioxidant.

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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There could be no finer moisturiser than honey and throughout history one can find numerous references to the skin benefits that honey can bring. The soothing, emollient and skin healing benefits of honey are being examined clinically in a number of leading hospitals throughout the world for wound healing and the treatment of burns.

Honey is good for skin care because it attracts and maintains moisture and acts like a moisturizer. Honey was used to treat boils, wounds, ulcers and burns. Locally it makes an ointment for sores, wounds and ulcers. It reduces irritation and is good to apply to chapped hands. It will afford relief for frostbite and will help to reduce swellings. Sword cuts were treated and dressed with honey and cobwebs. Its use dates back to ancient times, with Egyptian medical texts (circa 2600 and 2200 B.C.) mentioning honey in at least 900 remedies. Almost all early cultures universally hailed honey for its sweetening and nutritive qualities, as well as its topical healing properties for sores, wounds and skin ulcers. During wartime it was used on wounds as an antiseptic by the ancient Egyptians, Assyrians, Greeks, Romans, Chinese and even by the Germans as late as World War I.

Honey has long been consumed in foods and as an ingredient of food and beverages. The primary sugars of honey are also found as components of food and are considered to be Generally Recognized As Safe (GRAS) by the Food and Drug Administration (FDA). In addition to water and naturally occurring sugars, Honey contains varying levels of Beeswax. The safety of Beeswax and other waxes has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data concluded that Beeswax, Candelilla Wax, Carnauba Wax, and Japan Wax were safe for use in cosmetics and personal care products. In 2003, the CIR Expert Panel considered available new data on Beeswax and plant waxes and reaffirmed the above conclusion. This is a foodstuff and unlikely to cause any reaction on the skin.

CAS: 8028-66-8

Function: Emollient/ humectant/ moisturising.

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Tea tree oil: there has been extensive scientific study on its benefits, with promise of more evidence of its efficacy still to be published. Current data supports its use for antibacterial and antiseptic applications, treatment of acne, insect repellancy, antidandruff preparations and for the treatment of a wide range of skin complications.

First described in detail by members of the crew of Captain James Cook's expeditions in late 1700s, the plant gained widespread fame because of claims of its ability to treat skin ailments, cuts and burns. Extracts of the plant were used as topical antiseptics during World War II until superseded by more effective antimicrobial agents. The oil is more commonly used than the extract and has no anticipated or reported adverse effects when applied topically.

CAS: 85085-48-9

Function: Skin conditioning/Antimicrobial

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Argania Spinosa Kernel Oil (argan oil) is the fixed oil expressed from the kernels of the African tree (Morroco) Argania spinosa. Argan oil is widely used in the cosmetic industry within anti-ageing, anti-wrinkle and make-up products. Argan oil originates from Morocco. Argan oil helps in reducing the wrinkles and softening the skin. Argan oil is also known to protect the hydration of the skin and there are no reported adverse effects or expected adverse effects from the topical application of this oil.

Rich in natural sterols, this oil from Morocco is used by the local women to keep their skin soft, smooth and protected. Argan oil and preparations including argan oil have been used in traditional Moroccan medicine for centuries to cure skin diseases.

CAS: 223747-87-3

Function: Emollient/ skin conditioning.

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Simmondsia Chinensis (Jojoba) Seed Oil is an enigma, since if one looks at the chemical structure, one would expect it to be a wax. Nature’s only liquid wax has some extraordinary properties, since it has the protective power of a wax but with the light emollient softness of oil. It is reported in the literature to alleviate minor skin irritations and to be effective in the treatment of dry and sore skin. The oil also has extensive use in the care of the hair. Jojoba is a good solvent for sebum and is used to control and complement this skin’s natural moisturiser. The safety of Simmondsia Chinensis (Jojoba) Seed Oil, Simmondsia Chinensis (Jojoba) Seed Wax, Simmondsia Chinensis (Jojoba) Butter, Hydrogenated Jojoba Oil, Jojoba Esters, Hydrolyzed Jojoba Esters, Isomerized Jojoba Oil, Jojoba Alcohol and Synthetic Jojoba Oil has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and based on the available information concluded that Jojoba Oil and the related ingredients were safe for use as cosmetic ingredients.

Indians and Mexicans have for a long time used jojoba oil as a hair conditioner and restorer. There is a substantial body of anecdotal evidence that suggests that the wax is beneficial in alleviating minor skin irritations. Jojoba oil has been shown to significantly soften the skin as measured by viscoelastic dynamometry. Jojoba oil may be effective in alleviating the symptoms of psoriasis and in controlling acne outbreaks. It has been used medicinally for the treatment of burns and sores etc. Topical irritations such as sunburn and chapped skin appear to respond to topical jojoba therapy. A substantial body of anecdotal evidence suggests that the wax is beneficial in alleviating minor skin irritations. It is a liquid wax that acts as a skin protectant and emollient.

Function: Emollient

CAS: 61789-91-1

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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This butter is very similar in benefits to cocoa butter, but does not have the same chocolate smell associated with it. It has been studied in the treatment of burns, dermatitis, wounds, and inflammatory skin conditions. It is a rich skin emollient, which is used traditionally (by the tribes who collect and prepare it) to accelerate wound healing. The presence of a small amount of a component called allantoin (which is a well-proven healing agent) might justify this effect. The butter melts at body temperature and is quickly absorbed by the skin to leave it soft and supple.

Function: Emollient

CAS: 91080-23-8

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Aloe vera is of the most exciting ingredients for the care and treatment of the skin. The inner (parynchemal) gel is extracted by carefully filleting it from the leaf. The soothing, cooling and healing effects of the gel are well documented and there is extensive scientific proof to demonstrate that the gel has great benefit in both protecting and repairing the skin from radiation damage (solar and thermal), improving wound healing and restoring normal skin function.

Function: Emollient

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Whey is the water dispersable part of milk that is separated from the curd in the manufacture of cheese. Whey or milk plasma is the liquid remaining after milk has been curdled and strained. It is a by-product of the manufacture of cheese or casein and has several commercial uses. Sweet whey is manufactured during the making of rennet types of hard cheese like cheddar or Swiss cheese. Acid whey (also known as "sour whey") is obtained during the making of acid types of cheese such as cottage cheese. Because whey contains lactose, it should be avoided by those who are lactose intolerant. Dried whey, a very common food additive, contains more than 70% lactose. Liquid whey contains lactose, vitamins, protein, and minerals, along with traces of fat. People with an intolerance to milk products should be warned on the label. In the general population no adverse effects are exprected or reported.

Function: Skin conditioning.

CAS: 92129-90-3

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2-8% of milk (by weight), although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from lac, the Latin word for milk, plus the -ose ending used to name sugars. It has a formula of C12H22O11. It is not expected to show any adverse effects when applied to the skin at the levels used in cosmetic products.

Function: Humectant/ skin conditioning.

CAS: 63-42-3

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Cedrus atlantica. Cedarwood (Atlas Cedar). Country: France. Part used: wood. Traditional use: Good for stress related disorders. Said to soothe acne, eczema, arthritis and rheumatism. One of the most ancient oil traditionally used as a fixative in the perfumery industry. . Soothing woody aroma—helpful for oily skin and itchy scalp. Add to a fragrance jar in a wardrobe to repel moths. A very calming oil for respiratory problems. The oil is widely used for insect repellent activities and Turkish carpet shops are walled with cedarwood boards to deter the moths.

Function: Fragrance ingredient.

CAS: 8000-27-9

Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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Salicylic acid occurs naturally in plants such as wintergreen leaves, willow bark and sweet birch bark, although it can also be manufactured in the laboratory. It is similar to the compound used in the manufacture of aspirin (acetylsalicylic acid), and it has anti-microbial and anti-fungal properties so it acts as a preservative in product formulations. It is also a beta-hydroxy acid (BHA), making it gentler and less irritating than AHAs. In fact, its keratolytic (keratin-dissolving) properties have been used by dermatologists for decades. This mild peeling effect helps reduce blocked pores whilst also smoothing the look and feel of the skin, so it is used in acne treatments, anti-ageing products, anti-dandruff care, bath and body care, and depilatory creams.

The name salicylic acid (2-Hydroxybenzoic acid) is derived from the Latin salix meaning “willow,” from the bark of which it can be obtained. It is a beta hydroxy acid (BHA) and is probably best known for its use in anti-acne treatments. Salicylic acid was also isolated from the herb meadowsweet (Filipendula ulmaria, Syn. Spiraea ulmaria). Salicylic acid is known for its ability to ease aches and pains and reduce fevers. These medicinal properties, particularly fever relief, have been known since ancient times, and it was used as an anti-inflammatory drug.

Salicylic acid is a skin exfoliant and has been used in conjunction with AHAs (alpha hydroxy acids) or alone for this purpose. It is a key ingredient for the treatment of acne, psoriasis, calluses, corns and warts. It works as a keratolytic by increasing the rate of skin cell turnover causing the cells of the epidermis to shed more readily, this helps prevent pores from clogging and allows for new cell growth. It has also been used in shampoos for the treatment of dandruff and has some skin-whitening properties. Excessive use can cause photosensitivity.

The Food and Drug Administration (FDA) has reviewed the safety of Salicylic Acid and permits its use as indirect food additives. Salicylic Acid is approved for use in Over-the-Counter (OTC) drug products. Salicylic acid is widely used as an FDA approved safe and effective acne drug product. It is also approved for use in OTC drugs for corn, callus and wart removal, as well as in antidandruff OTC drug products. The safety of Salicylic Acid and its salts and esters has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated scientific data and concluded that Salicylic Acid was safe as used when formulated to avoid skin irritation and when formulated to avoid increasing the skin's sun sensitivity, or, when increased sun sensitivity would be expected, directions for use include the daily use of sun protection.

Function: Antidandruff/ hair conditioning/ keratolytic/ masking/ preservative/ skin conditioning.

CAS: 69-72-7

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Source: Dweck, Anthony. Handbook of Natural Ingredients (Dweck Books 4) . Dweck Data. Kindle Edition.

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The shelf life is the period during which the manufacturer has determined a cosmetic or personal care product to be best suited for use.

No regulations or requirements under current U.S. law require manufacturers to print specific expiration dates on the labels of cosmetics and personal care products. However, they are required to determine shelf life as part of their responsibility to substantiate safety.

In Europe, cosmetics products with a lifespan longer than 30 months must show a “period-after-opening” (PAO) time. PAO is the time, recorded in months, when the product will remain in good condition after the consumer has used it for the first time. A symbol of an open cream jar is usually used instead of words with the PAO alongside or inside the symbol. Although this symbol can be found on some U.S. cosmetics and personal care products, it is not required.

Any cosmetic or personal care product in Europe with a lifespan of fewer than 30 months must show a “best-before-the-end-of” (BBE) date. The lifespan is usually shown using the “egg timer” symbol followed by the date or with words abbreviated as BBE or Exp, followed by the date. Very few products are labeled with BBE dates because most are known to last more than 30 months.

Some products do not require any of these because the product will not deteriorate during normal use. Examples are aerosols, which are effectively sealed; perfumes with high alcohol content; or single-use packs.

Consumers should be aware that expiration dates are “rules of thumb.” Like food, product quality may decline before the expiration date without proper storage. Products that have been improperly stored (e.g., exposed to high temperatures or sunlight or opened and examined by consumers before final sale) may deteriorate substantially before the shelf life or expiration date.

Source: https://www.cosmeticsinfo.org/

What is INCI?

INCI names (International Nomenclature Cosmetic Ingredient) are systematic names internationally recognized to identify cosmetic ingredients. They are developed by the International Nomenclature Committee (INC) and published by the Personal Care Products Council (PCPC) in the International Cosmetic Ingredient Dictionary and Handbook, available electronically as wINCI.

Oversight for the INCI program is provided by PCPC as part of its mission to support the identification of the composition of personal care products, and publication of this information in a worldwide science-based Dictionary. PCPC is committed to ensuring that the Dictionary provides the world community with accurate, transparent, and harmonized nomenclature. By working closely with its international sister trade associations, and with other organizations around the world, PCPC strives to develop INCI names that accommodate differing labeling approaches described in national laws and regulations.

Why INCI?

There are many benefits to a uniform system of labeling names for cosmetic ingredients. Dermatologists and others in the medical community are ensured an orderly dissemination of scientific information, which helps to identify agents responsible for adverse reactions. Scientists are ensured that information from scientific and other technical publications will be referenced by a uniform name; and that multiple names for the same material will not lead to confusion, misidentification, or the loss of essential information. It also enables the cosmetic industry to track the safety and the regulatory status of ingredients efficiently on a global basis, enhancing its ability to market safe products in compliance with various national regulations. And finally, transparency is provided to consumers as ingredients are identified by a single labeling name regardless of the national origin of the product.

What INCI is not?

The designation of an INCI name for a cosmetic ingredient is an essential part of ingredient identification; however, just because an ingredient has an INCI name does not mean that the ingredient has been approved for cosmetics. The assignment of an INCI name to an ingredient also does not imply that the ingredient is safe, or that its use in a cosmetic product complies with the laws and regulations of the United States or other global regions. The safety and fitness of use for an ingredient, along with regulatory considerations, is carefully evaluated by the manufacturer as part of the development process before the product is marketed.

Source: https://www.personalcarecouncil.org/

European List of Notified Chemical Substances, that is, the list of substances marketed as of 18 September 1981 and notified under Directive 67/548/EEC. The latest edition of the ELINCS List can be consulted from https://op.europa.eu/en/publication-detail/-/publication/
c33bef79-ce30-43ab-accd-d596341cddff.

Source: https://ec.europa.eu/

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European Inventory of Existing Chemical Substances. An official inventory published on 15 June, 1990, that enumerates and describes the chemicals on the market of the European Union between January 1, 1971 and September 18, 1981 and identifies the chemicals being exempted of the mandatory 'precommercialisation' notification. The EINECS Inventory can be searched from different online sources including from the Publication Office of the European Commission.

Source: https://ec.europa.eu/

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Chemical Abstracts Service Registry. A registry of unique numeric identifiers allocated to each substance. A CAS Registry Number (abbreviated CASN, CASRN or CAS#) can contain up to 10 digits, divided by hyphens into 3 parts. The first part of the number has up to 7 digits; the second part has 2 digits, and the final part consists of a single check digit used to verify by computer the validity and uniqueness of the entire number. The full CAS Registry can be searched from different online sources.

Source: https://ec.europa.eu/

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Although less popular than o/w emulsions, these systems may be desirable when greater release of a medicating agent or the perception of greater emolliency is desired. Emulsifiers having an HLB range of 2.5 to 6 are frequently selected. When multiple emulsifiers are used, the predominant one is generally lipophilic with a smaller quantity of a hydrophilic emulsifier. These emulsions typically have a total of 45 to 80% oil phase.

Nowdays, formulators have become interested in more elegant w/o emulsions. This has been achieved by formulating with new emulsifying agents, emollient such as esters, Guerbet alcohols, and silicones. Selection of a suitable emollient depends on ability of the material to spread on skin with low tack, dermal compatibility, and perceived elegance by the user. In achieving this elegance, some researchers suggest a correlation of emollient and molecular weight of the emollients. In these studies, viscosity of w/o creams has correlated with molecular weight of the emollients used in test formulations.

High–molecular-weight co-emulsifiers formulated with high–molecular-weight emollients gave more stable w/o emulsions. The polarity of the emollients used was found to be important as well.

Emollients or mixtures of emollients with medium polarity gave test lotions the most desirable stability results. Anionic emulsifiers are generally inefficient w/o emulsion stabilizers, because more surface active agents are often needed to stabilize these emulsions. Sorbitan stearates and oleates are effective emulsifiers when
used at 0.5 to 5.0% sorbitan isostearates, being branched chain materials, give a very uniform particle size for w/o emulsions.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Oil-in-water emulsions typically contain 10 to 35% oil phase, and a lower viscosity emulsion may have an oil phase reduced to 5 to 15%. Water in the external phase of the emulsion helps hydrate the stratum corneum of the skin. This is desirable when one desires to incorporate water-soluble active ingredients in the vehicle. Oil droplets in emulsions have a lower density than the phase they are suspended in; to have a stable emulsion it is important to adjust the specific gravity of the oil and water phases as closely as possible.

Viscosity of the water phase (external phase) may be increased to impede the upward migration of the oil particles. Addition of waxes to the oil phase will increase specific gravity but have a profound effect on the appearance, texture, and feel on application to skin of the product. Increasing water-phase viscosity is one of the most common approaches.

Natural thickeners (alginates, caragenates, xanthan) and cellulosic (carboxymethyl cellulose) gums are used for this purpose.
Carbopol resin is perhaps the most popular gum thickener for contributing towards emulsion stability, especially at higher temperatures. The addition of a fatty amine to a Carbopol resin will further enhance stability by strengthening the interface of the water and oil phases through partial solubilization into the oil droplets. Electrolytes and cationic materials will have a destabilizing effect on anionic sodium carboxymethyl cellulose and should not be used together. Veegum, an inorganic aluminum silicate material, is also commonly used to thicken emulsions. Carbopol and Veegum may be used together to modify the characteristic draggy feel of Carbopol when used at the higher levels.

Emulsifier blends with HLBs ranging from 7 to 16 are used for forming o/w emulsions. In the blend, the hydrophilic emulsifier should be formulated as the predominate
emulsifier to obtain the best emulsion. A popular emulsifier, the glycerol monostearate and polyoxyethylene stearate blend is self-emulsifying and acid-stable. Emulsifiers are called self-emulsifying when an auxiliary anionic or nonionic emulsifier is added for easier emulsification of the formulation. Formulating with self-emulsifying materials containing nonionic emulsifiers permit a wide range of ingredient choice for the formulator, especially with acid systems. In alkaline formulations, polyoxyethylene ether–type emulsifiers are preferred with respect to emulsion stability.

An alternative to glycerol monostearate self-emulsifying emulsifier is Emulsifying Wax, National Formulary (NF). This emulsifier, when used with a fatty alcohol will form viscous liquids to creams depending on the other oil-phase ingredients used. Use levels may vary from 2 to 15%; at lower levels a secondary emulsifier such as the oleths or PEG-glycerides will give good stability. This system is good for stabilizing electrolyte emulsions or when other ionic materials are formulated into the vehicle. Polysorbates are o/w emulsifiers, wetting agents, and solubilizers often used with cetyl or stearyl alcohol at 0.5 to 5.0% to produce o/w emulsions.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Panthenol is the biologically active alcohol analogue of pantothenic acid, a vitamin of the B-complex group, which is a normal constituent of skin and hair. Pantothenic acid, also called Vitamin B5, carries out its function in the body as an element of co-enzyme A, a molecule composed of cysteamine, ATP, and pantothenic acid. This substance is present in all living cells and serves a vital role in the metabolism of a variety of enzyme-catalyzed reactions by which energy is released from carbohydrates, fats, and proteins.

Skin manifestations of pantothenic acid deficiency are well known, and include cornification, depigmentation, and desquamation. Pantothenic acid is an unstable substance. In topical preparations such as skincare, haircare, nailcare, and derma products, pantothenic acid is used in the alcohol form, called panthenol. Its use is based on its dual role as a vitamin precursor and as an ingredient with ideal cosmetic properties. When topically applied, panthenol is absorbed by the skin and can be bioconverted into pantothenic acid. As such it exerts all functions of
vitamin B₅.

Because it has a distinct humectant character, panthenol acts as a skin moisturizer. This hygroscopic substance not only provides water to the skin surface but it also penetrates deep into the epidermis and brings water to, and retains water in, the inside of the skin. Panthenol imparts a smooth, light feel to the skin without any greasiness or stickiness. Because it is well tolerated by the skin, it is an ideal and widely used ingredient in baby care products as well as in products for sensitive skin.
Topically applied panthenol stimulates epithelization as was shown by Weiser and Erlemann. Superficial wounds treated with creams containing 5% panthenol reduced the healing time by 30% compared with placebo. Favorable effects were also reported in many kinds of skin disorders accompanied by inflammatory reactions such as burns, nipple fissures, eczemas, and many others. Another application field of panthenol is, therefore, derma products for wound healing and for soothing of inflammatory disorders where it is usually incorporated in concentrations of 5%. The concentrations in cosmetics vary mainly from 0.3 to 2%.

The use of panthenol in haircare products goes back to the early 1960s, when inflammatory reactions on the scalp were treated with panthenol-containing creams. Panthenol not only showed a soothing effect but also had beneficial effects on the hair. Pantothenic acid is a natural constituent of human hair. Stuettgen applied tritium-labeled panthenol intracutaneously by injection and could show a transport of radioactive material into the hair. Stangl observed a significant increase of pantothenic
acid concentration in the hair after topical application of panthenol over longer periods.

Panthenol acts as a humectant for hair. It builds up a thin moisture film on the surface of the hair and gives hair shine without making it greasy. Panthenol also penetrates
into the hair cuticle and brings moisture to the cortex. This imparts good pliability and manageability properties to the hair, and improves its resistance to mechanical stress such as combing, brushing, and heat blowdrying.

Panthenol can also contribute to give hair more body. A thickening of the hair after 2 minutes exposure to a 2% water solution of panthenol was shown by means of scanning electron microscopy.

The main commercial forms are d-panthenol, dl-panthenol, and ethyl panthenol. All these forms are soluble in e.g., water, ethanol, and propylene glycol, but insoluble in fats and oils. Ethyl panthenol is an ether and available either as d-form or a racemic mixture of d- and l-form. Biological activity has only the d-form, because only d-pantothenic acid is incorporated into coenzyme A.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Skin scrub agents or body polishers are solid materials from natural origin (fine powder of seeds or shells of different vegetables), or are obtained by chemical synthesis (tiny beads of styrene or polyethylene). When the scrub agent–containing body-cleansing product is rubbed or massaged onto the skin, fine solid particles remove superficial skin horny layer by mechanical abrasion, leaving behind a fresh, smooth skin surface.

They are the easiest additives for the consumer to perceive. Scrubbing particles can be suspended in liquid body cleanser thanks to structuring polymers like xanthan gum or carrageenan, which build a viscoelastic network in the surfactant matrix. The scrubbing agent must be carefully selected when formulating facial cleansers. The skin on the face is more sensitive or delicate than that of the rest of the body. For facial application, the formulator should orientate his choices towards, e.g., soft clays or melting jojoba beads.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Amphoteric surfactants are amino acid derivatives; their net charge varies with the pH in solution. At pH below the isoelectric point they are positively charged in aqueous solution and can consequently adsorb more easily onto the skin. Alkyl chain length can also significantly act on the skin feel; some betaines based on C16/C18 cuts provide more greasy, refattened feel but also have detrimental effect on foam. Polydimethylsiloxane grafted with a betaine moiety leads to an amphoteric surfactant combining substantivity, refattening properties as well as silicone typical skin feel profile.

Some nonionics are used for their emollient properties and excellent afterfeel; e.g., sucrose and methyl glucose esters as well as sucrose ethers. Fatty acid alkanolamides are often referred to as refatteners; these are not lipids but they confer a greasy slippery feel to the foam and impart a particular afterfeel on the skin that subjectively compares with refatting. Several mild anionic surfactants are known to provide improved skin feel (afterfeel) by themselves, e.g., sarcosinate, taurate, acylglutamate, and isethionate. Fatty acids–protein condensates salts also act as conditioning aids, imparting a pleasant, smooth feel to the skin. The inclusion of fatty acids in soap and syndet bars contributes to enhance skin feel during and after use, and produces creamier lather. Phosphoric acid fatty esters deliver soap-like skin feel: slipperiness during use, and very good rinseability leaving skin feeling ‘‘clean’’ and powdery.

Benefits brought by additional skin conditioning agents are sometimes hidden by a mild or very mild cleaning-surfactant system delivering by itself very good skin feel properties; the sensorial baseline is high to start with and the increment in performance brought by skin feel agent is leveled off, and sometimes not even perceivable. It is, however, important to notice that several mild anionic and most of the nonionic surfactants, if they provide a pleasant afterfeel, are characterized by a ‘‘water feel’’ (feel in solution) that is often unpleasant, with rough and drag feel sensations.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Polymeric materials can interact both with protein of the skin surface and with skin lipids. Parameters influencing the interaction between skin surface and the polymers are as follows:

1. The positive charge density: the more cationic the character of the polymer, the better the polymer interaction with negatively charged skin surface.
2. The hydrophobicity of polymer: grafting of hydrophobic moieties on the polymer backbone favor van der Waals interactions with hydrophobic areas of the keratin.
3. The molecular weight of the polymer: the higher the polymer size, the more its substantivity to the skin (film-forming properties). However, very low–molecular weight polymers can easily penetrate the skin surface chinks and as such adsorb into the superficial stratum disjonctum.
4. The nature of surfactants neighboring the polymer in the finished product: the polymer can interact with surfactants either through their charges or through hydrophobic interactions; also, competition between polymer and surfactants for skin anchoring sites can occur. In both cases, deposition and adsorption of polymer onto the skin surface is weakened.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Lecithin is a natural mixture of polar and neutral lipids; the word lecithin is also used as the trivial name of a particular phospholipid: phosphatidylcholine. Main vegetable
sources of lecithin used in personal-care products are soybean and maize, egg yolk is practically the only animal source of lecithin used in cosmetics and toiletries. The percentage of polar lipids and their fatty acid pattern are characteristic of the lecithin source.

Bare lecithin, a secondary product of Soya oil extraction, typically contains 60 to 70% polar lipids (mainly phospholipids, namely phosphatidylcholine, and glycolipids) and a remaining 25 to 35% Soy oil. This raw lecithin is further fractionated, purified, and chemically modified to allow easier processing and formulation in toiletry products. Emollient, refattening, and moisturizing properties of lecithin are guided by its content in phospholipids.

Lecithin softens, nourishes, and refattens the skin; it provides a nongreasy, long-lasting skin feel and improves foam feel and quality (creaminess, slipperiness, richness).
Ready-to-use mixtures of phospholipids in surfactant solutions, free of residual Soya oil, are commercially available for an easy incorporation in liquids or bars; some of these compounds allow formulation of clear products.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Lanolin is extracted from sheep wool grease; it is a complex mixture of esters of high molecular weight lanolin alcohols (aliphatic alcohols, sterols, and trimethyl sterols) and of lanolin acids; free lanolin alcohols, acids, and lanolin hydrocarbons are minors. Lanolin alcohols and lanolin oil are recommended as superfatting agents in soaps.

Ethoxylation of the hydroxyl groups of lanolin or of its derivatives leads to hydrophilic, water-soluble lanolin compounds, offering a broad range of useful emollients to the formulator. Some moderately to highly ethoxylated derivatives, recommended for their good emolliency and moisturization properties, are processable in liquid skin cleansers with limited impact on foam profile; as an example, the 75 mol ethoxylated lanolin does not depress foam and is recommended as skin conditioner in soaps, liquid body-cleansing products, and bubble baths. Medium ethoxylates lanolin alcohols have limited impact on foam performances of body cleansing liquids; lower ethoxylates can be formulated in bars.

Propoxylated lanolin alcohols are lipophilic emollients used in soap bars and in other cleansers based on synthetic surfactants. Alkoxylated lanolin derivatives are obtained by reaction with mixtures of propylene and ethylene oxides in various ratios; they are more soluble than ethoxylated lanolin. They serve as refattening and foam stabilizing agents. Esterification of lanolin fatty acid with isopropyl alcohol provides a range of esters of various molecular weights. Medium molecular weight esters are used as superfatting agents in soaps.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

The CTFA dictionary defines emollients as: ‘‘cosmetic ingredients which help to maintain the soft, smooth and pliable appearance of the skin; emollients function by their ability to remain on the skin surface or in stratum corneum to act as lubricant, to reduce flaking, and to improve the skin’s appearance.’’ Emollients are also described as refatting additives or refatteners in the case of bath products. The word refattener refers to substances improving the lipid content of the upper layers of the skin; they prevent defatting and drying out of the skin. Several emollients showing strong lipophilic character are identified as occlusive ingredients; they are fatty/oily materials that remain on the skin surface and reduce transepidermal water loss. The CTFA dictionary defines occlusives as: ‘‘cosmetic ingredients which retard the evaporation of water from the skin surface; by blocking the evaporative loss of water, occlusive materials increase the water content of the skin.’’

Overall, emollients and refatteners are oils and fats derived from natural origins or obtained by chemical synthesis; they are classified in nonpolar (paraffins and isoparaffins) and polar substances (esters and triglycerides); their chemical structure influences the interaction with the skin surface and affects their sensorial properties. As a class, they comprise lipids, oils and their derivatives, fatty acid esters, lanolin derivatives, and silicones and their organofunctional derivatives. Originally, emollients were developed for use in leave-on skin care products; formulation technology can aid the deposition of refatting additives on the skin from wash-off products and avoid that they rinse off with the surfactants; nevertheless, the large dilution factor in both products remains a significant hurdle for skin end benefit perception (except in bath oils).

Emollients and refatteners will provide after feel, but will also influence skin feel during usage, foam feel, and most of the time foam quantity and quality. The more hydrophobic the refattening additive, the more negative its impact on flash foam generation, foam quantity, and stability. In other respects, the more lipidic the material, the better its skin substantivity, and the easier the efficacy documentation; proof and substantiation of claims is of more and more importance in the frame of the Sixth Amendment of European legislation for cosmetics and toiletries.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

Unlike Newtonian fluids, non-Newtonian fluids possess shear-rate dependent viscosities. In addition to shear-rate dependent viscosities, non-Newtonian
fluids also exhibit elastic stresses when subjected to high shear rates. The usefulness of the elastic response varies with application.
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At low shear rates, i.e., near at rest conditions, non-Newtonian fluids exhibit high viscosities that are relatively insensitive to shear rate and characterized by zero shear viscosity. The zero shear viscosity is known to be highly sensitive to the molecular weight and concentration of the rheological additives. The rates of deformation associated with this region include sedimentation and levelling forces, and one can tailor the zero shear viscosity to combat these forces. At moderate shear rates the decrease in viscosity versus shear rate helps when pouring and pumping these fluids. At high shear rates it is found that a second Newtonian plateau in viscosity is reached usually characterised by the so-called infinite viscosity. The shear forces in this area are close in magnitude to forces developed during rubbing and spraying exercises. The low viscosities exhibited by the rheological additives in this region imply low resistance to rubbing and thus a smooth sensation of the substance during its application.

Source: Handbook of Cosmetic Science and Technology - André O. Barel, Marc Paye, Howard I. Maibach

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