Silicone Elastomer (Dimethyl Siloxane Elastomer, Fumed Silica)

by | Jul 15, 2021

What is it? Silicone elastomer is a super fine, slippy, gorgeous powder ingredient that improves all kinds of colour cosmetics. It helps with oil control, improves skin feel, and helps disguise imperfections.

If you’ve used Silica Dimethyl Silylate and Silica Microspheres, I’d say silicone elastomer exists somewhere between them. It’s slippy like silica microspheres, but thickens a bit more like Silica Dimethyl Silylate (SDS).
INCI Dimethyl Siloxane Elastomer, Fumed Silica (generic)
Appearance Ultrafine white powder
Usage rate Up to 20%
Texture Ultra-smooth and rich
Scent None
Solubility Insoluble, but so fine that it is indistinguishable.
Why do we use it in formulations? Basically, it makes everything better! It blurs fine lines, improves slip, and can improve wear time by helping control sebum. It improves colour/pigment payoff and makes our cosmetics feel more expensive/luxurious. TKB lists the usage rate as up to 20%, but I’ve noticed big differences including it at less than 1%!
Do you need it? No, but if you love making high-end colour cosmetics I definitely recommend it.
Refined or unrefined? Silicone Elastomer only exists as a refined product.
Strengths It’s a potent and highly effective way to level up your cosmetic formulations.
Weaknesses  I have only found silicone elastomer for sale from TKB Trading in the USA.  They ship internationally, but I know that can get expensive.
Alternatives & Substitutions Silica Microspheres would be my first suggestion. Keep in mind that when you’re making substitutions in cosmetics even very small changes can dramatically impact the performance, wear time, and consistency of the cosmetic. I worked on a formulation that included 0.25% Silica Dimethyl Silylate (SDS), which didn’t work—I switched that 0.25% to silicone elastomer and it was perfect.
How to Work with It Avoid inhaling silicone elastomer; I find it is far less floaty/inhalation prone than Silica Dimethyl Silylate and Silica Microspheres.
Storage & Shelf Life Stored somewhere cool, dark, and dry, silicone elastomer should last three years or more.
Tips, Tricks, and Quirks Read the reviews for this product on TKB Trading to get some fun ideas for using it!
Recommended starter amount 30g (1.06oz) will last a long time!
Where to Buy it  I have only found silicone elastomer for sale from TKB Trading.

Some Formulations that Use Silicone Elastomer

Silicone gel (Cyclopentasiloxane, Dimethicone/Vinyl Dimethicone Crosspolymer)

by | Jul 15, 2021

What is it? Silicone gel is basically gelled cyclopentasiloxane. It has all the slippy goodness of cyclopentasiloxane with added viscosity.

Mine is from TKB Trading and the SDS states it is comprised of 90–98% cyclopentasiloxane and 2–10% of the gelling ingredient (Dimethicone/Vinyl Dimethicone Crosspolymer).
INCI Cyclopentasiloxane, Dimethicone/Vinyl Dimethicone Crosspolymer
Appearance Crystal clear, viscous gel
Usage rate 0–100%, though I generally start around 10%. Usage is similar to Cyclomethicone + other cyclo-siloxanes, but with added viscosity.
Texture Incredibly silky smooth and slippy, with wonderful skin feel and soft powderdry dry-down.
Scent None
Absorbency Speed Very fast
Flash Point 76°C (169°F)
Solubility Oil, silicones
Why do we use it in formulations? Just like cyclomethicone and other cyclo-siloxanes, silicone gel adds wonderful slip to our products and helps reduce tackiness. Small concentrations add a really gorgeous, expensive-feeling skin feel. Higher concentrations of cyclomethicone help “lighten” products, speeding up dry down/absorption speeds. Because silicone gel is viscous, it can also add body and viscosity to our products, depending on the concentration used.

Learn more with this encyclopedia entry: Cyclomethicone + other cyclo-siloxanes.
Do you need it? Generally no, but if you are interested in making high-end colour cosmetics I definitely recommend it.
Refined or unrefined? Silicone gel only exists as a refined product.
Strengths Silicone gel is an easy way to add silky viscosity and luxurious slip to our formulations.
Weaknesses Silicone gel is not widely available—I’ve only found it in the USA and Australia.
Alternatives & Substitutions Cyclomethicone + other cyclo-siloxanes would be the best place to start, though you will lose the viscosity of the gel. Depending on the formulation this might be ok, or you may need to replace that viscosity with something else.
How to Work with It Silicone gel should be cold-processed due to its low flash point; if you need to heat it, do it slowly, carefully, and briefly!
Storage & Shelf Life Stored somewhere cool, dark, and dry, silicone gel should last at least three years.
Tips, Tricks, and Quirks There are 22 different products on UL Prospector with this INCI, but from reading the descriptions they vary in viscosity, so the INCI doesn’t tell the whole story.
Recommended starter amount 50g (1.76oz)
Where to Buy it My silicone gel is from TKB Trading, and if you want to be certain you’re getting the same product I have I’d recommend purchasing it from them if you can. Making Cosmetics carries a product with the same INCI, but from the photos it is far thicker (solids are listed at 20% vs. 2–10% for TKB’s product)—if you have that, I’d just it at about half the rate and make up the difference with more cyclomethicone. LotionCrafter also has an INCI-identical product; they describe it as a “clear fluid gel”, and from the photos it looks like it might be the same as (or very similar to) the product sold by TKB Trading.

New Directions Aromatics Australia also has an INCI-identical product; it looks similar to the Making Cosmetics product.

Some Formulations that Use Silicone Gel

Cyclomethicone + other cyclo-siloxanes

by | Aug 15, 2020

What is it? Cyclomethicone is an ultra-light volatile silicone ingredient. “Cyclomethicone” is a generic/broad term for one or more cyclic siloxanes, primarily cyclotetrasiloxane (D4), cyclopentasiloxane (D5), and cyclohexasiloxane (D6). Learn more here.

There are other cyclic siloxanes (D3–D7) but D4, D5, and D6 are the primary ones for cosmetic use. Cyclotetrasiloxane (D4), cyclopentasiloxane (D5), and cyclohexasiloxane (D6) are sold as isolated ingredients, but I’ve only ever found cyclopentasiloxane (D5) available to homecrafters.

If you check product datasheets you might find out that the “cyclomethicone” you’re looking at is almost entirely cyclopentasiloxane (D5). Check the datasheets from your supplier to learn more about the specific products you’re looking at. For example, this datasheet for the cyclomethicone sold by Windy Point shows it is 99–100% cyclopentasiloxane (D5), with a small amount of cyclotetrasiloxane (D4).

From my research, I’d avoid cyclotetrasiloxane (D4) where possible as Health Canada has concerns about it accumulating in the environment.
INCI Varies; check with your supplier. It’s usually “Cyclomethicone” or a list of the component cyclic silicones comprising that particular product, like “Cyclotetrasiloxane (and) Cyclopentasiloxane”. If you are purchasing an isolated cyclic siloxanes the INCI should reflect that (eg. Cyclopentasiloxane).
Appearance Thin clear liquid
Usage rate I’ve seen widely varying maximum usage levels; everything from 10% to 95%. Check with your supplier for the specific product you have.
Texture Ultra-light, slippy, luxurious.
Scent Nothing noticeable
Absorbency Speed Very fast
Approximate Melting Point Liquid at room temperature
Solubility Oil, silicones
Why do we use it in formulations? Cyclomethicone adds wonderful slip to our products and helps reduce tackiness. Small concentrations add a really gorgeous, expensive-feeling skin feel. Higher concentrations of cyclomethicone help “lighten” products, speeding up dry down/absorption speeds.

It is commonly used as a diluent in hair oils to create products that don’t leave the hair looking greasy. A small amount of oil will be diluted in a larger amount of cyclomethicone; when that is applied to the hair the cyclomethicone will readily evaporate, leaving a tiny amount of well-distributed oil behind on the hair.

In cosmetics, you’ll find it in all kinds of cream cosmetics, where it provides body to the cosmetic and then evaporates readily after application, leaving behind the pigment without any added oil that would compromise wear time.
Do you need it? No, but if you love making cosmetics and/or have hair that is not very tolerant of oils, cyclomethicone is a wonderful ingredient to have on hand.
Refined or unrefined? Cyclomethicone only exists as a refined product.
Strengths Cyclomethicone is a very versatile ingredient that improves the skin feel of anything I’ve ever tried it in.
Weaknesses The biggest weakness of cyclomethicone (and other silicones) is all the negative myths about it. These myths include the idea that silicones suffocate the skin, cause acne, and are bad for sensitive skin. If you have concerns about silicones, please review these resources:

You certainly don’t have to use silicones in your products if you don’t want to, but don’t avoid it based on misinformation 🙂
Alternatives & Substitutions You can generally use cyclomethicone and cyclopentasiloxane interchangeably. I have both and can’t really tell a difference between the two. You can also try Dimethicone 1.5, which is lightweight and volatile (not to be confused with Dimethicone 350 or other non-volatile silicones).

There are several natural silicone alternatives on the market now, like “LuxGlide” and “LexFeel”. The ones most suitable for replacing cyclomethicone are “LuxGlide N5” and “LexFeel N5”.

You could also try ultralight emollients/esters like Isoamyl laurate, Coco-Caprylate, isoamyl cocoate, C12-15 alkyl benzoate, or Neossance® Hemisqualane, but even these lightweight emollients are significantly heavier than cyclomethicone and will create a heavier end product, especially if the cyclomethicone is used at high concentrations to create an ultra-light end product.

Isododecane is similar to cyclomethicone in terms of viscosity and volatility, but I find it is even more volatile. You could try blending it with an ultralight emollient as a cyclomethicone alternative (I’d probably start with about 90% isododecane/10% ultralight emollient).
How to Work with It Include it in the oil phase of your products; it should be cold-processed as it will readily evaporate (and possibly burst into flame) when heated (the flashpoint is 77°C [169°F]).
Storage & Shelf Life Stored somewhere cool, dark, and dry, cyclomethicone has an indefinite shelf life. Keep it away from sparks and heat sources as the flashpoint is 77°C (169°F)
Tips, Tricks, and Quirks “Silicones… aren’t biodegradable, but they are degradable – they degrade in the environment, and turn back into silica (sand), carbon dioxide and water.” –Lab Muffin
Recommended starter amount 100mL (3.3fl oz)
Where to Buy it  Buy it from an online DIY ingredient supplier or Amazon.

Some Formulations that Use Cyclomethicone

Silica Dimethyl Silylate

by | Feb 10, 2020

What is it? Silica Dimethyl Silylate is an ultra-lightweight fumed silica—it’s really different from silica microspheres.
INCI Silica Dimethyl Silylate
Appearance Loose, white powder
Usage rate 0.1–30%
Texture Fluffy, lightweight powder. If you get any on your hands it is immediately so dry that your fingers will feel skiddy, like they’re covered in chalk.
Scent Nothing noticeable
Solubility Insoluble
Why do we use it in formulations? Silica Dimethyl Silylate is insanely absorbent. When combined with oils it creates transparent oil gels, which is very cool, and also reduces the oily feel. It also contributes viscosity to liquid cosmetics like liquid eyeliner and lipstick, and helps reduce pigment settling (very helpful for makeup applied to parts of the face that move/crease a lot). It is so dang absorbent that it also provides quite a lot of grip to things—I’ve used it in hair products and it is like a supercharged dry shampoo.
Do you need it? You only need Silica Dimethyl Silylate if you’re very passionate about making makeup.
Refined or unrefined? Silica Dimethyl Silylate only exists as a refined product.
Strengths Very cool multi-use ingredient that improves the performance of many cream and liquid cosmetics by offering thickening, oil control, and pigment settling/bleeding.
Weaknesses It’s pretty niche; if you don’t make makeup or hair products you likely won’t use it all that much.
Alternatives & Substitutions You’ll need to determine what the Silica Dimethyl Silylate is doing in a formulation. If it’s there mostly for oil absorption (in a hair product, for instance) something like silica microspheres or calcium carbonate might do the trick. For oil thickening, you could try a fatty thickener like stearic acid (though that will add quite a lot of richness that Silica Dimethyl Silylate wouldn’t add).
How to Work with It Wear a dust mask! Silica Dimethyl Silylate is insanely light and floaty—just opening the bag will send it floating around the room. It can be hot or cold processed; I like to add it to my oil phase.
Storage & Shelf Life Stored somewhere cool, dark, and dry, Silica Dimethyl Silylate should last indefinitely.
Tips, Tricks, and Quirks You can use Silica Dimethyl Silylate to make your own version of this product!
Recommended starter amount 30g (1.06oz) or less—an ounce of this stuff is a lot, volume-wise.
Where to Buy it  Buy it from an online DIY ingredient supplier or Amazon.

Some Formulations that Use Silica Dimethyl Silylate

Dimethicone 350

by | Jan 24, 2020

What is it? Dimethicone 350 (also known as Dimethylpolysiloxane) is a mid-weight, non-volatile silicone.
INCI Dimethicone
Appearance Semi-viscous clear liquid
Usage rate Up to 80%, though I typically use it in the 1–5% range
Texture Rich, slippy, smooth. Typical of silicones.
Scent Nothing noticeable
Absorbency Speed Slow
Approximate Melting Point Liquid at room temperature
Solubility Oil, silicones
Why do we use it in formulations? Dimethicone 350 adds wonderful slip to our products and helps reduce tackiness. Small concentrations add a really gorgeous, expensive-feeling skin feel. It helps improve spreading, offers skin protection, and conditions the skin and hair. It can also reduce soaping in lotion formulations. It is also an FDA approved skin protectant.
Do you need it? No, but I do love how small concentrations of Dimethicone 350 allow me to work with higher concentrations of good-for-skin ingredients that can make products feel tacky. It’s also a wonderful, super-easy way to improve slip & skin feel.
Refined or unrefined? Dimethicone 350 only exists as a refined product.
Strengths Dimethicone 350 is a very versatile ingredient that improves the skin feel of anything I’ve ever tried it in. It is non-irritating (suitable for those with sensitive skin) and will not aggravate conditions like Pityrosporum Folliculitis (a.k.a. fungal acne).
Weaknesses The biggest weakness of Dimethicone 350 is all the negative myths about it. These myths include the idea that silicones suffocate the skin, cause acne, are toxic, and are bad for sensitive skin. Dimethicone and other silicones have been studied and reviewed extensively by experts around the world and have been continuously found to be not only very safe, but beneficial to the skin. If you have concerns about silicones, please review these resources:

You certainly don’t have to use silicones in your products if you don’t want to, but don’t avoid it based on misinformation 🙂
Alternatives & Substitutions In products where you are using Dimethicone 350 at 5% or less, you could try a higher viscosity version, like Dimethicone 500 or Dimethicone 1000. With that low of a usage rate, the dimethicone will be diluted so much that the thicker version is unlikely to impact the end product much (if a very low viscosity is important to the final product [i.e. if it’s supposed to mist] then swapping in a higher viscosity of dimethicone probably isn’t the best idea).

There are several natural silicone alternatives on the market now, like “LuxGlide” and “LexFeel”. The ones most suitable for replacing Dimethicone 350 are “LuxGlide 350” and “LexFeel 350”. I find the natural alternatives do not offer the same level of slip and richness as Dimethicone 350, so you may want to increase the concentration to compensate.

You could also try rich, slippy oils as an alternative (something like oat oil), though these will not offer the same level of de-tack-ifying and skin smoothing. The importance of this is very formula dependent, and I also find perceptions of stickiness/tackiness are very personal. If you’re not very sensitive to stickiness (or just plain ol’ don’t mind it) you are less likely to notice the loss of silicone in a formulation.

Dimethicone 1.5 is not a good alternative for Dimethicone 350; the 1.5 version is ultra-thin and lightweight, and evaporates quickly. It is much closer to Cyclomethicone and Cyclopentasiloxane than Dimethicone 350.
How to Work with It Include it in the oil phase of your products; it can be hot or cold processed. Check with your supplier for the specific product you have as recommendations can vary.
Storage & Shelf Life Stored somewhere cool, dark, and dry, Dimethicone 350 has an indefinite shelf life.
Tips, Tricks, and Quirks The “350” in Dimethicone 350 indicates viscosity. The higher the number, the more viscous the dimethicone. Dimethicone 500 and 1000 are also fairly readily available to home crafters.
Recommended starter amount 100mL (3.3fl oz)
Where to Buy it  Buy it from an online DIY ingredient supplier or Amazon.

Some Formulations that Use Dimethicone 350

Quaternium-90 Sepiolite and Quaternium-90 Montmorillonite (Thickening Clay)

by | Apr 18, 2019

What is it? Quaternium-90 Sepiolite (and) Quaternium-90 Montmorillonite (Thickening Clay) is an alkyl quaternary ammonium clay. It’s basically a fine powder derived from clay that has been treated to create a powder that, when used in small amounts, thickens oil-based products and helps keep pigments in suspension. It is generally recommended for use in cosmetics.

This product is manufactured by Eckart America and is called GARAMITE-7308 XR.

While this product certainly helps prevent pigment settling, it does not prevent it entirely. Too much can make products feel dry on the skin, so simply using more isn’t always a good approach, either.
INCI Quaternium-90 Sepiolite (and) Quaternium-90 Montmorillonite
Appearance Off white fine powder
Usage rate The suggested rate is 1–3%
Texture Smooth ultrafine powder
Scent Nothing noticeable
Charge Cationic (positive)
Solubility Insoluble
Why do we use it in formulations? Quaternium-90 Sepiolite (and) Quaternium-90 Montmorillonite does four very cool things. 1) It thickens oil-based concoctions. 2) It contributes to a more matte finish. 3) It helps keep powdered pigments in suspension. 4) It helps improve adhesion/wear time in colour cosmetics.
Do you need it? If you like creating coloured cosmetics I would highly recommend it!
Refined or unrefined? Quaternium-90 Sepiolite and Quaternium-90 Montmorillonite only exists as a refined product.
Strengths Excellent pigment suspension, thickening, and skin feel at low concentrations. It’s also very easy to work with!
Weaknesses Too much can make the end product drying (I find even 3% can create products that are more drying than I’d like, especially in lip products). It’s also pretty dang hard to source outside the USA.
Alternatives & Substitutions I don’t have any great recommendations. You can try using white kaolin clay in its place, but this will not have the thickening/suspending properties or the added adhesion.
How to Work with It Take care not to inhale the clay—wear a dust mask. This product is very lightweight and floaty, and very easy to accidentally inhale. Stir/blend it into the oil phase of your concoctions at pretty much any point—the manufacturer stipulates it can be incorporated at any time. Low shear mixing is sufficient—I usually use my MicroMini Mixer to blend everything together.
Storage & Shelf Life Stored somewhere cool, dark, and dry, Quaternium-90 Sepiolite and Quaternium-90 Montmorillonite should last at least five years.
Tips, Tricks, and Quirks Learn more about Alkonium Clays here.
Recommended starter amount 30g (1.06oz)
Where to Buy it The only place I’ve found it for sale is TKB Trading.

Some Formulations that Use Quaternium-90 Sepiolite and Quaternium-90 Montmorillonite (Thickening Clay)