CYCLOMETHICONE
CYCLOMETHICONE
Cyclomethicone is a mixture of low molecular weight volatile cyclic siloxanes, in varying proportions.
Cyclomethicone provides excellent stability and is an ideal carrier for color cosmetics, make-up, skin creams and hair care products.
Cyclomethicone is a light weight silicone that is a popular addition to lotions, creams and hair conditioners due to its silky skin feel and ability to help carry oils and nutrients to the skin and hair without leaving a greasy feeling.
Cyclomethicone is widely used a base fluid in body sprays and room sprays.Cyclomethicone (D5) is a polydimethylcyclosiloxane that is composed of Decamethylcyclopentasiloxane (CAS# 541‐02‐6).
The product is clear, tasteless, essentially odorless, non‐greasy and non‐stinging.
Due to their varying rates of evaporation, low surface tensions (high spreadability), and non‐greasy feel, Cyclomethicones are used as base fluids, carrying agents and wetting agents in a wide range of personal care products.
Cosmetic applications include: room sprays, body sprays, antiperspirants, skin creams, skin lotions, suntan lotions, bath oils, hair care products etc.
Cyclomethicone is a colorless, odorless, liquor-free, clear silicone fluid, and act as solvent for various oil-based items.
Cyclomethicone is produced when hydrolysis of dichloride produces a mixture of cyclic dimethyl siloxanes and polydimethylsiloxane, with further distillation in presence of strong potassium hydroxide (KOH) takes place, then polymer mixture of cyclomethicone is form.
It is also known as decamethylcyclopentasiloxane. It has a cyclical structure instead of a straight design of dimethyl silicone.
Cyclomethicone is regularly utilized as base solvents to mix fragrance oils, scents, and other cosmetic products.
They dissipate rapidly and are miscible with a variety of cosmetic oils, waxes, hydrocarbons, and silicone oils.
This property of cyclomethicone makes them a critical component in beauty care products as base solvents.
Cyclomethicone is insoluble in water. Moreover, they are low surface strain liquids, which permit them to spread easily on a superficial level they are applied to.
Cyclomethicone helps in the simple utilization of make-up and is utilized in hair care items since they improve the quality of hair while giving a clean and healthy appearance.
Furthermore, cyclomethicone’s product helps in improving the presence of scars and reduces irritation.
Major application of cyclomethicone is in skincare and cosmetic formulation where it helps to improve the texture and sensory feel of the product on the skin.
It is expected to drive the growth of the global cyclomethicone market.
Cyclomethicone-based paints and coatings are used in various industry such as tire manufacturing industry and shipping industry as it improves adherence, waterproofing and resistance to extreme conditions. Cyclomethicone is also used for glass and specialty cleaners, lubricants, penetrating oils
Cyclomethicones are unmodified silicones that possess a cyclical structure rather than the chain structures of dimethyl silicones. Low heat of vaporization and the ability to select a desired vapor pressure has led their use as cosmetic vehicles. Unmodified silicones stay on or near the surface of the skin. Not only are the molecules too big to physically enter past the upper living cells, they associate with the upper layer of drying skin but they also cannot penetrate cell membranes due to their large size.
Cyclomethicones evaporate quickly after helping to carry oils into the top layer of epidermis.
From there, they may be absorbed by the skin.
Cyclomethicones perform a similar function in hair care products by helping nutrients enter the hair shaft.
Cyclomethicones are cyclic circular silicones of low molecular weight that evaporate quickly.
Their volatility, excellent spreading and lubrication make them ideal carriers for other ingredients and excellent light conditioners for hair and skin.
Nongreasy, cyclomethicone leaves no oily residue or buildup and imparts a soft silky feel to skin.
Cyclomethicone is preferred for its conditioning, viscosity controlling, and water-repelling properties. It is an excellent solvent and can be found in countless products.
Cyclomethicone is documented to be an anti-static agent, non-greasy, non-sticky, and is acclaimed for giving a slippery feel and a dry non-cooling sensation on evaporation.
Cyclomethicone evaporates quickly and does not leave behind any residue. This commands application in formulating deodorants and antiperspirants.
Cyclomethicone makes spreading products a breeze because of its unique fluidity.
Cyclomethicone provides stability to the formulation and prevents it from splitting.
Cyclomethicone is used to deposit active ingredients on the skin and hair, thereby enhancing the efficacy of the formulation.
Cyclomethicone is used in serums, lotions, hair sprays, face and body mists, sunscreens, non-sticky oils, etc.
HOW IT WORKS-
Cyclomethicone works by carrying the key ingredients of a formulation into the skin and hair for better absorption.
Lacking penetrative powers, it simply forms a layer over the skin.
Cyclomethicone makes the surface slippery and then evaporates owing to its volatility.
Its functions (INCI)
Antistatic : Reduces static electricity by neutralizing electrical charge on a surface
Emollient : Softens and smoothes the skin
Hair conditioner : Leaves hair easy to comb, soft, soft and shiny and / or confers volume, lightness and shine
Humectant : Maintains the water content of a cosmetic in its packaging and on the skin
Skin conditioning : Keeps the skin in good condition
Solvent : Dissolves other substances
Viscosity controlling : Increases or decreases the viscosity of cosmetics
CYCLOMETHICONE is classified as :
Antistatic
Emollient
Hair conditioning
Humectant
Solvent
Viscosity controlling
CAS Number 69430-24-6 / 556-67-2 / 541-02-6 / 540-97-6
EINECS/ELINCS No: – / 209-136-7 / 208-764-9 / 208-762-8
INN Name: cyclomethicone
Chem/IUPAC Name: Cyclopentasiloxane, Decamethyl; Cyclic dimethylsiloxane pentamer; Cyclopolydimethylsiloxane; Decamethylcyclopentasiloxane
Cyclotetrasiloxane (D4)
Cyclopentasiloxane (D5)
Cyclohexasiloxane (D6)
Cyclomethicone is not one type of silicone, but a whole mixture of them: it’s a mix of specific chain length (4 to 7) cyclic structured silicone molecules.
There seems to be a confusion on the internet whether Cyclomethicone and Cyclopentasiloxane are the same. They are not the same, but Cyclopentasiloxane is part of the mixture that makes up Cyclomethicone.
All the silicones in the Cyclomethicone mixture are volatile, meaning they evaporate from the skin or hair rather than stay on it.
This means that Cyclomethicone has a light skin feel with none-to-minimal after-feel.
It also makes the formulas easy to spread and has nice emollient properties.
What Is CYCLOMETHICONE?
Cyclomethicone is a general term describing both individual and/or a mixture of cyclic siloxane materials that have many uses and are found in a variety of consumer products.
These materials are derived from the natural elements silicon and oxygen.
Why is CYCLOMETHICONE used in cosmetics and personal care products?
D5 and D6 are the predominant cyclomethicones used in cosmetics and personal care products, due to their excellent skin and hair conditioning properties.
Cyclopentasiloxane (D5)
Decamethylcyclopentasiloxane (D5) is an organosilicon compound with the formula [(CH3)2SiO]5. It is a colorless and odorless liquid that is slightly volatile
Cyclomethicone 5 is member of cyclomethicone, which are a group of liquid methyl siloxanes that have low viscosity and high volatility.
Cyclomethicones are cyclic in structure with a monomer backbone of one silicon and two oxygen atoms bonded together.
Cyclomethicone 5 is used in cosmetic and personal products as a skin emollient.
Cyclomethicone 5 (D5) is a clear, alcohol-free and odorless liquid, added to personal skin care products to give them a smoother texture that is more easily applied to the skin.
Because molecules of this chemical are too large to enter human pores, and don’t tend to block the active ingredients from entering the skin, cyclomethicone is a commonly used as a skin emollient ingredient
D5 is colorless, odorless, non-greasy, and water-thin.
It doesn’t get absorbed into the skin.
Rather, it evaporates quickly away from it. T
his property makes it a useful ingredient in cosmetic products that need to dry quickly, like antiperspirants and hair sprays.
D5 is known for being able to evaporate and dry quickly. Silicones are also known to repel water and glide easily.
This is why they are commonly used as ingredients in lubricants and sealants.
Use
Cyclopentasiloxane (D5) is classified as a cyclomethicone.
Such fluids are commonly used in cosmetics, such as deodorants, sunblocks, hair sprays and skin care products.
Cyclopentasiloxane (D5) is becoming more common in hair conditioners, as it makes the hair easier to brush without breakage.
D5 is also used as part of silicone-based personal lubricants. D5 is considered an emollient
They are also known to form a protective barrier on the skin and hair. This can help you detangle your hair, prevent breakage, and reduce frizz.
D5 can be found in a wide range of personal care products. Examples include:
hair spray
sunscreen
antiperspirant
deodorant
hair conditioner
shampoo
hair detangling products
waterproof mascara
foundation
eyeliner
concealer
moisturizer with SPF
eye shadow
hairstyling gel and lotion
lipstick
It sometimes appears on a label as decamethylcyclopentasiloxane or D5. It may also be put under the broader category name of cyclomethicone.
It’s different from another siloxane known as dimethicone or polydimethylsiloxane (PDMS).
Cyclomethicone D5 is a volatile polydimethylcyclosiloxane composed mainly of cyclotetrasiloxane.
The product is clear, tasteless, essentially odorless, non-greasy and non-stinging.
Benefits:
• Imparts soft silky feel to the skin
• Excellent spreading
• Leaves no oily residue or build up
• Detackification
• Non-greasy
Applications:
• A base fluid in a number of personal care products, with excellent spreading, easy rub-out and lubrication properties together with unique volatility characteristics.
• Can be used in antiperspirants, deodorants, skin creams, lotions, bath oils, suntan and shaving products, make-up, nail polishes.
• In sticks, it has the right balance between volatility and spreading.
EC / List no.: 614-966-1
CAS no.: 69430-24-6
CYCLOMETHICONE 5
OCTAMETHYLCYCLOTETRASILOXANE (D5)
CYCLOPENTASILOXANE, DECAMETHYL-
CYCLOPENTASILOXANE (D5)
Cyclosiloxanes, di-Me
IUPAC names
Cyclicdimethylpolysiloxane
Cyclomethicone
Cyclopolydimethylsiloxane
Cyclosiloxanes, di-Me
decamethyl-1,3,5,7,9,2,4,6,8,10-pentaoxapentasilecane
Dimethyl Cyclosiloxanes
Dimethylcyclopolysiloxane
Dimethylcyclosiloxanes
Mixed Cyclosiloxanes
Polydimethylcyclosiloxane
SILICONE FLUID
EC / List no.: 208-764-9
CAS no.: 541-02-6
Mol. formula: C10H30O5Si5
Decamethylcyclopentasiloxane
decamethylcyclopentasiloxane
Decamethylcyclopentasiloxane
D5
Decamethylcyclopentasiloxane; D5
CYCLOPENTASILOXANE
D5
decamethyl-1,3,5,7,9,2,4,6,8,10-pentaoxapentasilecane
Decamethylcyclopentasiloxan
DECAMETHYLCYCLOPENTASILOXANE
Decamethylcyclopentasiloxane
decamethylcyclopentasiloxane
Decamethylcyclopentasiloxane
decamethylcyclopentasiloxane, D5
Dimethylpolysiloxan
Baysilone D5G
BRB CM 50
Calsil CV 50
Calsil CV50
Calsil IV 50
Calsil IV50
D5
DECAMETHYLCYCLOPENTASILOXANE
DOW CORNING(R) 245 FLUID
EXO T216S
KF995
PENTAMERE D5
SB32
SF 1202
SHTSF405
SILBIONE PENTAMERE D5
Silsoft 1202-LT
SL25
T-216B
TSF405
XE14-B9042C
Production and polymerization
Commercially D5 is produced from dimethyldichlorosilane. Hydrolysis of the dichloride produces a mixture of cyclic dimethylsiloxanes and polydimethylsiloxane.
From this mixture, the cyclic siloxanes including D5 can be removed by distillation.
In the presence of a strong base such as KOH, the polymer/ring mixture is equilibrated, allowing complete conversion to the more volatile cyclic siloxanes
Cyclomethicone D4 is rarely used as a cosmetic ingredient.
D4 can also be present at very low residual levels (generally <0.1%) in D5 and D6, since it is used as a starting material in the production of those cyclomethicones.
During this manufacturing process, virtually all of the material is consumed leaving only a tiny amount of D4.
EC / List no.: 209-136-7
CAS no.: 556-67-2
Mol. formula: C8H24O4Si4
Cyclic dimethylsiloxane tetramer
Cyclotetrasiloxane, 2,2,4,4,6,6,8,8-octamethyl-
Cyclotetrasiloxane, octamethyl-
KF 994
NUC silicone VS 7207
Octamethylcyclotetrasiloxane
octamethylcyclotetrasiloxane; [D4]
Oktamethylcyklotetrasiloxan
OMCTS
Silicone SF 1173
UC 7207
Union carbide 7207
VS 7207
Cyclohexasiloxane (D6)
EC / List no.: 208-762-8
CAS no.: 540-97-6
Mol. formula: C12H36O6Si6
Dodecamethylcyclohexasiloxane
D6
Dodecamethylcyclohexasiloxane; D6
CAS names
Cyclohexasiloxane, 2,2,4,4,6,6,8,8,10,10,12,12-dodecamethyl-
IUPAC names
2,2,4,4,6,6,8,8,10,10,12,12-dodecamethyl-1,3,5,7,9,11-hexaoxa-2,4,6,8,10,12-hexasilacyclododecane
D6
Dodecamethyl cyclohexasiloxane
DODECAMETHYLCYCLOHEXASILOXANE
Dodecamethylcyclohexasiloxane
dodecamethylcyclohexasiloxane, D6
Trade names
Baysilone SF 1217
Dodecamethylcyclohexasiloxane
DOW CORNING(R) 246 FLUID
Silsoft 1217
Cyclomethicone ingredients are used in cosmetic products where eventual complete evaporation of the siloxane carrier fluid is desired.
In this way Cyclomethicone is useful for products like deodorants and antiperspirants that need to coat the skin but not remain tacky afterward.
Cyclomethicone provides other important product performance benefits such as facilitating a smooth texture and an even application.
Thus, Cyclomethicone may also be found in sunscreens, shampoos, conditioners, moisturizers, lotions, etc.
CHEMICAL STRUCTURE OF CYCLOMETHICONES
The basic structure is common to all cyclomethicones: a cyclic backbone of siloxane units (i.e., silicon and oxygen with molecules of carbon and hydrogen attached, all very common elements found in nature).
Shorthand nomenclature is based upon the number of siloxane groups that are in the cyclic structure.
Thus, cyclomethicone D5 (also known as cyclopentasiloxane) has five of these groups, cyclomethicone D4 (also known as cyclotetrasiloxane) has four, etc.
Created as an alternative emollient to existing products, cyclomethicone’s chemical structure allows for easy application across the skin while reducing pore entry and skin stickiness.
Skin care products delivering dimethicone and essential oils now rely on cyclomethicone for easy application of products.
This element differs from other silicones because its silicones have a lower molecular weight that remains unmodified.
It also possesses a cyclical structure.
These elements make a cosmetic delivery system because of the low heat levels required for vaporization.
Silicones in an unmodified state remain on or near the skin’s surface in part because of the molecule’s size, which prevents passage beyond the outer parts of the skin.
Cyclomethicone is a completely clear liquid ingredient that gives skin care products the quality of being able to spread easily and smoothly, especially across skin.
Its structure is cyclical and has a low molecular weight.
Cyclocmethicone’s structure limits its ability to penetrate through the dermis layer, which means the molecules mingle with dry skin before evaporating quickly.
It has many uses and is in skin lotions, fragrances, and hair conditioners.
Because Cyclomethicone evaporates quickly when applied to the skin, some have experienced skin and eye irritation.
However, it is a vegan, gluten-free, and soy-free ingredient, and is deemed safe to use by the FDA in concentrations of less than 10 percent.
Cyclomethicones are clear, odorless liquids utilized in skincare products to give your skincare that silky texture.
Cyclomethicones are a type of silicone, so they help products to apply evenly and smoothly to your skin.
There are several types of silicones used in skincare and cosmetic products.
You may already be familiar with silicones, probably the one you are most acquainted with is dimethicone.
Cyclomethicones have a similar function to dimethicone in that they help improve the texture of products, improve the appearance of scarring, improve the water-resistance of products, and emulsify the product.
However, Cyclomethicones are also better at delivering active ingredients to the skin.
Cyclomethicones are a subclass of silicone; there are many different cyclomethicones in that subclass.
Cyclomethicones are sometimes also called cyclosiloxanes, they are different names for the same class of chemicals.
The two most commonly used cyclomethicones are cyclopentasiloxane and cyclohexasiloxane; you may have seen these ingredients somewhere near the bottom of your product’s ingredients list.
Cyclomethicones have a ring-shaped structure that makes it more volatile or less stable.
This instability allows cyclomethicones to evaporate when applied to your skin—making cyclomethicones a great ingredient for products that need to go on smoothly but not remain sticky after application.
As all the cyclomethicone eventually evaporates, it leaves behind the other key components in the product to work their magic.
This action of evaporation makes it an excellent carrier ingredient.
What Are The Benefits of Cyclomethicone?
The main benefit of cyclomethicones is their ability to improve your product’s texture and sensory feel on the skin.
However, cyclomethicones are also thought to help improve the appearance of dryness, are used for the appearance of scars, and may help to reduce irritation.
Texture
Cyclomethicones work to produce a smooth, silky feeling product.
The structure of cyclomethicones, like most silicones, prevents the molecule from penetrating the skin.
The structure allows for cyclomethicone containing products to glide over uneven texture and pores so that the product can be distributed evenly.
They ensure that all areas of the skin are receiving the key ingredients in your product.
Dry skin
A study published in Skin Pharmacology and Physiology looked into the way cyclomethicones interacts with the skin.
The study investigated the occlusive nature of the cyclomethicones. Occlusive substances work by creating a physical barrier between the skin and the air.
The study’s results suggested that cyclomethicones are not an occlusive ingredient, and due to cyclomethicones being an unstable molecule, the evaporation means that they don’t form this barrier.
These results are excellent news for congestive skin types, more on that later.
However, occlusive barriers are generally useful for drier skin types, and it prevents moisture loss.
The rate at which the evaporation occurs provides the skin with a little bit of this protective barrier and may help to improve the appearance of dry skin and flakiness.
Scarring
Research into cyclomethicones has suggested their use in improving the appearance of scars in conjunction with other silicone ingredients.
A study published in the Journal of Cutaneous and Aesthetic Surgery determined that silicone gel preparation significantly enhances the appearance of superficial, hypertrophic, and keloid scars.
While this research has not been conducted into cyclomethicones specifically, it is related to the broader subgroup of silicones.
Many of the silicone gel preparations contain cyclopentasiloxane or cyclohexasiloxane, which is used at the volatile element to deliver the other silicone ingredients to the skin.
Who Should Use Cyclomethicones?
Cyclomethicone products are suitable for most skin types, including congested, dry, or sensitive skin types, as well as skin types that may have damaged skin barrier integrity.
Acne and clogged pores
There is a general misconception that silicone-containing products cause breakouts.
These claims remain unsubstantiated by peer-reviewed research.
This misconception comes from anecdotal evidence, and while that can be a useful tool for driving areas of research, it does not replace an in-depth study.
However, an explanation for this anecdotal evidence is that silicone-based products can trap sweat or other skincare products that potentially cause breakouts closer to the skin.
This theory hasn’t been tested but has some validity given the function of silicones.
To avoid this, make sure you wash your face after using silicone products and exercising.
It would also be useful to check the ingredients in your other skincare products to see if they could be contributing to the breakouts.
Studies have determined that most silicone products are non-comedogenic (not clogging) and allow the skin to breathe.
Silicones and cyclomethicones do not enter the pores, where the formation of blemishes occur.
Silicones will also evaporate to varying degrees away from the skin, reducing the barrier effect.
Cyclomethicones naturally form less of a barrier on the skin as they disappear more readily, minimizing the likelihood of congestion even further.
Sensitivity
Cyclomethicones can be beneficial for sensitive skin types as the barrier effect of products containing cyclomethicones can help to reduce the skin’s contact with irritants.
If you have sensitive skin, be mindful of the other ingredients in your product that may irritate, such as fragrance, because the cyclomethicones will deliver these ingredients effectively to the skin.
In some cases, minor irritation may occur from the use of silicones, but it’s not usually the source of sensitivity in a product.
Dry skin
Cyclomethicones may help to improve the appearance of dryness and flaking on the skin.
As mentioned, silicones and cyclomethicones help to form a temporary breathable barrier on the surface of the skin, which may help to prevent moisture loss.
Research is ongoing into the uses of silicones and cyclomethicone in issues that affect skin barriers such as psoriasis, eczema, and dermatitis.
Cyclomethicone vs Dimethicone
The main difference between cyclomethicones and dimethicone is that cyclomethicone has the ability to evaporate from the skin where dimethicone does not.
This allows cyclomethicones to be a better carrier to deliver key ingredients to the skin.
Dimethicone works best in products where the desired outcome is for the product to stay on the skin for prolonged periods of time.
This makes dimethicone great for foundations, concealers, and rich moisturizers.
Safety
Cyclomethicones have been well studied and are safe for their indicated uses.
The main issue with cyclomethicones is that in some people, they can cause some minor irritation of the skin and eyes.
The report produced by the Cosmetic Ingredient Review group stated that cyclomethicones are safe for cosmetic use.
Other Uses
Some of the other uses for cyclomethicones include use in products that reduce the appearance of scars; it is present in gels designed for burns and may help in wound healing.
Cyclomethicones are often used in hair care products to help improve the appearance of the hair, making it shiny and glossy.
It is also undergoing research for use in head lice treatments.
Cyclomethicone is a clear, odourless cosmetic-grade silicone.
It is non-greasy and evaporates quickly, making it ideal for use as a base in room and linen mists, as well as in cosmetic products.
Add to lotions and creams for a silky, powdery feel.
May also be used in hair care products to add shine and reduce frizzing.
Outstanding as a base for dry oil body sprays, as well as room and linen sprays.
Mild and non-irritating, Cyclomethicone makes for an excellent cosmetic ingredient for skin care aimed towards all sorts of skin types, predominantly sensitive or problem.
It helps to provide good spreading when added to formulations such as lotions and creams.
As well as this it possesses some emolliency, so it makes for an excellent addition to moisturisers and other related cosmetics, adding to its already wide range of uses.
Although it is only oil soluble, when paired with an emulsifier, Cyclomethicone makes excellent perfumes, toners and sprays as it leaves skin feeling clean, dry and soft.
Cyclomethicone also helps to prevent an unpleasant tacky feeling on the skin so it is best used for skin care cosmetics, however it works exceptionally well in shampoos and conditioners to prevent frizziness in humidity as well as promoting static control. Often added at the oil phase of a cosmetic formulation.
OTHER USES OF Cyclomethicone
Cyclomethicone is a Solvent for the cleaning of water-sensitive surfaces, textiles, fibers like paper, or particularly aged and soiled acrylic.
Cyclomethicone has an extraordinary good wettability for all kinds of greasy dirt.
Cyclomethicone can be used as a replacement for perchlorethylen.
All Cyclomethicone products have a very low heat of vaporization, thus the vaporization occurs without a noticeable cooling.
The INCI name, cyclomethicone, refers to a family of cyclic dimethyl siloxanes that includes cyclotetrasiloxane (D4), cyclopentasiloxane (D5), and cyclohexasiloxane (D6), a family that has come under increased environmental scrutiny in recent years.
One of the main reasons for this scrutiny is the volatility of cyclomethicone.
With the problems and concerns of cyclomethicone, the quest for a replacement material that provides a dry feel but is not volatile becomes paramount.
Key areas where this family of materials is used include antiperspirants, colour cosmetics and as a base solvent to blend with fragrance oils and perfume oils.
Cyclomethicone is a clear, odourless silicone. It leaves a silky-smooth dry feel when applied to the skin.
Cyclomethicone has a cyclic structure with alternating silicone-oxygen atoms.
Cyclomethicone provides a low heat of vaporisation and low vapour pressure, which leads to their use as cosmetic vehicles.
In other words, the feel correctly or incorrectly has been associated with volatility.
However, the physical chemistry that results in the dry feel of cyclomethicone is a complex one.
Volatility is but one aspect of the complex phenomenon that contributes to a dry feel in a solvent used in cosmetics.
Typically volatile organic compounds are flammable and dangerous to incorporate into a cosmetic formulation.
Along with volatility, other considerations that impact upon selection of a D5 replacement include viscosity, surface tension reduction (which affects spreadability), flammability of the solvent, effects of the solvent on skin, and cost.
Clearly, a D5 replacement that is flammable, defatting and expensive is unacceptable.
The assumptions we used in evaluating the suitability of materials as D5 replacements:
• Non-volatile.
• Not flammable.
• Dry feel.
Volatility
Volatility is the ability of the compound being tested to evaporate under the temperatures at which the compound is used in formulation.
For cosmetic products, this temperature is ambient (~25°C).
It has generally been accepted that cyclomethicone compounds provided this feel because they evaporate quickly after helping to carry oils into the top layer of the epidermis.
The assumption that volatility is required for dry feel is due to the fact that historically D4 has a dry feel and is volatile.
D5 has replaced D4 in formulations and consequently has been found acceptable in many cosmetic formulations as a D4 replacement, but is it volatility that is primarily responsible for the dry feel?
Personal care products are unique in that they are not applied at elevated temperatures as are many industrial products.
It is therefore unreasonable to talk about volatility of a cosmetic solvent at elevated temperatures.
The temperature of application is more typically 20°C than 200°C, yet we measure volatility at elevated temperatures.
If one looks at a temperature of 20°C, the volatility more closely resembles what might occur in topical cosmetic products.
There is some controversy surrounding the environmental impact of this ingredient. Chemicals used in hair and skin products can make their way into the environment when they’re rinsed down the drain. These products may then accumulate and harm fish and other wildlife.
Cyclopentasiloxane was once considered hazardous to aquatic wildlife. It was found in laboratory studies to be bio-accumulative in some aquatic animals. This prompted a Canadian review board to conduct more research about the environmental impact of this chemical.
A 2011 review concluded that D5 didn’t pose a danger to the environment. The review board found no evidence of toxicity to any organism. The board also didn’t find evidence that the chemical can build up to high enough concentrations to cause problems in animals.
A 2013 study found that the chemical evaporates during typical use. Only a very small fraction of the chemical finds its way down the drain and into the environment. This amount is considered negligible by the study authors.
Contrary to the earlier studies, recent evaluation by the European Union regarding environmental accumulation of D5 has resulted in limits on concentrations used in wash-off cosmetics to less than 0.1%, effective January 31, 2020.
Products containing cyclopentasiloxane can be used safely on your hair and skin with minimal personal risk. It helps your skin and hair products dry quickly and spread more easily. It can make the hair feel silky without weighing it down.
Though there is a concern that this ingredient can disrupt hormones in your body, research shows that it doesn’t get absorbed into the skin in high enough doses to cause harm.
It is possible that D5 could accumulate in water supplies when used in concentrations above 0.1% and when washed off before evaporating. This possibility has led to increased regulation of its use in some countries.