Faulkner’s new book Coloring the Cosmetic World: Using Pigments in Decorative Cosmetic Formulations is the latest color cosmetic technology book from Allured Publishing. The book promises to provide a comprehensive look at all aspects of this subject and overall meets and exceeds that goal. Its blend of practical information and theoretical information make it a valuable addition to any cosmetic chemist’s bookshelf.

Book organization

This book covers the subject of colorants in 12 chapters. It also includes extensive appendices, glossary, and bibliography.

The first chapter provides a solid background for the subject of colorants, covering topics of color theory, effects on people, physics and finally an introduction color chemistry. This is particularly helpful for a cosmetic chemist just getting started with the subject.

The next four chapters take an in-depth look at the key aspects of choosing a colorant. These include regulatory considerations, stability, color esthetics, and the economics of color. The regulatory chapter provides a description of the requirements of the US, EU and Japan. It also includes a nice historical perspective of how things ended up the way they are now. This chapter is particularly helpful because it suggests what may happen to color regulations in the future.

In the chapter on color stability, the author describes the various colorants that a formulator will likely use in her product. Two parts of this chapter will be most helpful to cosmetic chemists including a chart which lists the compatibility of colorants with a number of solvents and a section of colored photos of numerous powdered colors. No doubt this will become a section of the book that gets referred to often.

One of the most useful chapters in the book is the one on color esthetics. Here the author takes us through dozens of colorants describing the shade that can be produced, which product forms it is normally used in and both positive and negative aspects of using the color. This chapter will save time for any color cosmetic formulator.

The chapters in the second half of the book deal with the specifics of formulating with colorants, testing, and newer pigment technology. The pigment dispersion chapter focuses on creating color cosmetic products and it would have been nice to see this expanded to cover more types of formulations. The color testing chapter is brief but detailed methodologies in the appendix more than make up for any shortcomings.

The final chapters of the book discuss some specific color technologies including surface treated pigments, effect pigments, specialty pigments and natural colorants. Each chapter provides a blend of interesting background science and practical knowledge that can be used at the bench right away.

Colorful ending

The book’s last chapter is possibly one of the most entertaining. It does not discuss much about colorants but rather provides some sage advice from a color formulator who has spent 40 years in the pigment and cosmetic industries. This is bound to make any cosmetic formulator smile.

There is a number of useful pages included after the primary text. This section makes up almost a third of the book and includes the aforementioned appendix on color testing methodologies, an extensive listing on the patent history of colorants, a glossary, and an index. The only weakness in this part is the index which would have benefited from more listings.

The title of this book suggests it will provide a detailed look at the world of pigments used in color cosmetics and it certainly delivers. For cosmetic formulators who are just getting started, this could be the one and only book on color that you will ever need. And its detailed regulatory information, practical formulating tips, testing protocols, and description of pigment and color technology make it an indispensable reference for all color cosmetic scientists.

This is a guest post by Gary Neudahl who is currently Product Application Manager, Personal Care Ingredients, for the HallStar Company and is based at the HallStar Manufacturing and Technical Center in Bedford Park IL USA.

In this post, we move from general hand & body care to sun protection. With the issuance of a new FDA Final Rule that goes into effect later this year, there has been a heightened interest in the OTC Sunscreen Drug Products category. This rule requires sun protection products for the U.S. marketplace to move a step closer to the quality of protection provided in the EU, Japan, Australia and most of the rest of the world. And with rising instances of skin cancer in young adults, it is none too soon.

Sunscreen UVB history

For many years, sunscreens marketed in the U.S. have provided protection against UVB radiation (290 – 320 nm), the rays that are responsible for sunburn, that is comparable to that of similarly rated products around the world. A sunscreen’s sun protection factor (SPF) is the ratio of the minimum erythemal dose (MED) – the amount of UV radiation it takes to turn the skin slightly red – of skin protected with sunscreen to the MED of unprotected skin. Higher SPFs mean greater protection against burning (and, presumably, skin cancer). Sounds good, but UVB is not all the sun delivers!

UVA protection

Sunscreens marketed in the U.S. must soon also provide protection against UVA radiation (320 – 400 nm), the rays that are commonly known as the “tanning rays,” to avoid sporting a warning label. That’s because the longer wavelengths of UVA rays allow them to penetrate more deeply into the skin than UVB rays — through the outer layer, the epidermis, all the way to the dermis. The only visible short-term effect of UVA irradiance is skin tanning, and short wavelength UVA exposure actually has a beneficial effect in children, converting 7-dehydrocholesterol into vitamin D, thereby reducing the incidence of rickets, a bone-softening disease.

But as with UVB irradiation, long-term UVA exposure has detrimental effects. In the dermis, it degrades collagen, a critical structural component, resulting in sagging and wrinkling of skin. And UVA radiation contributes to the incidence of basal cell and squamous cell carcinomas, as well as malignant melanoma. Like UVB radiation, it decreases the number of Langerhans cells, which lowers resistance to infection.

Limiting the sun’s effects

So there are good reasons to limit sun tanning, and one way to do that is to apply a broad-spectrum sunscreen (one that significantly reduces the amount of both UVB and UVA rays that reach the skin). A sunscreen’s UVA Protection Factor (PFA) is determined by measuring persistent pigment darkening (PPD), the appearance of brownish skin pigmentation within three hours of exposure to UVA. Products with higher PFA provide better resistance to persistent pigment darkening. Rather than using this in vivo measure of UVA protection, the FDA chose to use the critical wavelength – the wavelength at which the integral of spectral absorbance curve reaches 90 percent of the integral over the UV spectrum from 290 up to 400 nm.

Therefore, the higher the critical wavelength, the greater the level of UVA protection. The FDA’s new Final Rule requires a critical wavelength of at least 370 nm (and an SPF of at least 15) for a sunscreen to be called “broad spectrum” and to avoid a “Sun Alert” warning that includes the statement “This product has been shown only to help prevent sunburn, not skin cancer or early skin aging.”

Formulation

Sun protection includes not only classic “beach wear” sunscreens, but also the “daily wear” sun protection that is built into lip balms, color cosmetics and general skin care products. Consumer product forms from which sun protection may be delivered include creams, lotions, gels, sprays, and sticks. Because we looked at emulsion-based lotions last month, we’ll now examine sunscreen sprays, with the following typical composition:

Volatile Carrier: 50 – 80%
Humectants: 0 – 4%
Sunscreen Active Ingredients: 2 – 40%
Fragrance: 0 – 0.5%
Water-Resistance Polymer: 0.8 – 2%
“Label Copy” Ingredients: 0 – 0.5%
Sunscreen Solvents: 0 – 10%
Other Active Ingredients: 0 – 0.5%
Photostabilizers: 0 – 6%

The most common volatile carrier for sunscreen sprays is anhydrous ethyl alcohol, which produces a solution rather than an emulsion, so fewer ingredients are required. The alcohol must be essentially anhydrous to promote sunscreen active ingredient solubility.

FDA Sunscreen Monograph

The sunscreen active ingredients are selected from the FDA monograph, using authorized levels and combinations (e.g., Homosalate and Octisalate or Octinoxate with Avobenzone). Generally speaking, the higher the level of sun protection, the greater the quantity and number of sunscreen active ingredients that will be utilized. Zinc Oxide and Titanium Dioxide, although approved for use, are unsuitable in alcohol-based sprays because they are not soluble in alcohol, and their high densities would result in their rapid settling during storage.

Sunscreen ingredients

A water resistant polymer, such as Acrylates/Octylacrylamide Copolymer, is required for two reasons. First, it helps retain the sunscreen on the skin and, second, it promotes uniform deposition on the skin, preventing the sunscreen solution from pooling in crevices, which results in disproportionate protection of the crevices and a lower than expected overall level of sun protection. A uniform layer of sunscreen produces the maximum possible sun protection ratings.

As the levels of solid organic sunscreen active ingredients (e.g., Avobenzone and Oxybenzone) are increased, the liquid sunscreen active ingredients may prove inadequate to keep them in solution, particularly at low temperature. If these solid sunscreen active ingredients crystallize on the skin after the alcohol has evaporated, a reduction in sun protection level and an increased potential for skin irritation will result. Consequently, addition of sunscreen solvents (e.g., Butyloctyl Salicylate, Dimethyl Capramide and/or Diisobutyl Adipate) may be required to ensure adequate solid organic sunscreen active ingredient solubility.

Photostabilizers, the next ingredient category, are particularly important for any sunscreen utilizing Avobenzone as a sunscreen active ingredient. This is because, although Avobenzone strongly absorbs UVA and UVB radiation, it is prone to degrading as a result, markedly reducing its UV absorbing capabilities, especially when Octinoxate, a strong UVB absorber, is also present. While solvent polarity optimization can be used to some effect (by using sunscreen solvents of higher than usual polarity, such as those listed in the previous paragraph), triplet state quenchers such as Polyester-8 and Undecylcrylene Dimethicone are frequently more effective. When Octinoxate and Avobenzone are used together, the photostabilizer of choice is singlet state quenching Ethylhexyl Methoxycrylene, which can remove the existed state energy from Avobenzone perhaps a thousand times faster than even triplet state quenchers, allowing substantial photostabilization of this notoriously photolabile combination.

Humectants are substance that have an affinity for water and so increase the water-holding capacity of skin. They help to counter the otherwise drying effect of the alcohol used as a volatile carrier in sunscreen sprays.

Fragrance (parfum) is sometimes added, if for no other reason than to mask the base “sunscreen” odor of the product. When a signature fragrance is part of the market positioning, up to about 2% fragrance may be present. When hypoallergenic and/or “no fragrance” claims are made for the product, carefully selected essential oils, botanical extracts and/or individual synthetic chemicals may be added to control product odor without needing to use the word “fragrance” on the label.

We’ve covered “label copy” ingredients before. These are ingredients, often added at vanishingly low levels, that are included not because they are functional, but because they are useful as marketing “hooks” to catch consumer interest and garner initial product trial.

Last on our list are other active ingredients. These are ingredients, such as Vitamin E derivatives, that are added for functional effect, but not necessarily to enhance sun protection properties. If anti-aging ingredients such as Reservatrol, Retinol, Retinyl Palmitate, Ubiquinone and/or Cholecalciferol are included, all of which are photolabile (not photostable), they can be substantially photostabilized by the incorporation of the aforementioned singlet state photostabilizer Ethylhexyl Methoxycrylene.

If you have additional questions about sunscreen sprays, or about sunscreens in general, you may contact the author at gneudahl@hallstar.com.

On the cosmetic science forum someone posed this question, “Where can I find the monograph for cosmetics?” It’s an interesting question for a number of reasons so I thought I would make a complete blog post out of it. To answer this question, we need to step back and discuss what a monograph is.

FDA Monographs

A monograph is essentially a recipe book that tells formulators exactly the ingredients, doses, and formulations they can use when creating an over-the-counter drug. It also gives the exact claims that can be made about the product and describes other labeling requirements.

This means that the technical answer to the original question about finding monographs for cosmetics is “nowhere because they do not exist.” Monographs are for drugs, not for cosmetics.

Cosmetic monographs

While that answer is technically correct it is also incomplete because there are a number of cosmetic like products that are classified as over-the-counter (OTC) drugs here in the United States.

Here is a list of cosmetic/OTC products that are governed by an FDA monograph. If you are formulating one of these products, you will have to follow the rules described in the OTC monograph.

1. Anti-acne products – This monograph describes 40 different ingredients that can be used for anti-acne. Rule was finalized in 1990 although there was some action in 2010 on Benzoyl Peroxide.

2. Toothpaste & anti-cavity products – This monograph gives a list of over 20 ingredients that can be used to fight cavities. The final rule was issued in 1995.

3. Topical anti-fungal – Products that are topically applied to places that need anti-fungal effects (diaper rash, feet, etc). Final rule was originally passed in 1993.

4. Anti-microbial products – There is a long list of ingredients that can be used for topical anti-microbial products. For most of the antimicrobial ingredients, the final rule has not yet been issued. It is suggested you follow the proposed rules when formulating.

5. Antiperspirant – This monograph is for products that are designed to stop sweating. The final monograph was originally issued in 2003. It lists 26 active ingredients that you can use.

6. Astringents – These are classified as skin
protectants. The final rule was originally issued in 2003.

7. Corn & Callus removers – Definitely a niche product but some cosmetic companies might want to create these formulations.

8. Dandruff products – If you are planning to create an anti-dandruff shampoo, then you have to follow the rules of this monograph. The final monograph was issued in 1991 & revised in 1992.

9. Hair growth / hair loss – The final monograph for these types of products was issued in 1989 and includes nothing that works. However, in 1994, Minoxidil was switched from a perscription drug to an OTC. It remains the only non-perscription option.

10. Nailbiting products – There is a monograph for products that are designed to stop people from biting their nails. Who knew? The final monograph was issued in 1993.

11. Psoriasis – These products are designed to treat the condition of psoriasis. The tentative monograph was issued in 1986 and has yet to be finalized. Only a couple of active ingredients are allowed including Coal Tar and Salicylic acid.

12. Skin bleaching – Skin lightening products are OTCs in the US. The tentative final monograph was issued in 1982 but it has yet to be finalized. There are only 2 active ingredients acceptable for skin lightening.

13. Sunscreen – It’s been a long time coming but a final monograph on this topic was issued in 2011.

14. Topical analgesic – These products find a wide variety of application and cover products such as those designed for diaper rash, cold sore treatments, poison ivy treatments, and others.

15. Wart remover – Products that are used to remove warts. The final monograph was issued in 1990 but updated in 1994. Thirteen active ingredients are listed.

Monographs and the cosmetic chemist

It is crucial that you understand the monographs for any product that you are formulating. They list exactly the raw materials you can use, the amounts, and even dictate the claims you can make. And while it may be a bit restrictive from a formulating standpoint, it is useful to know exactly what ingredients have been tested and shown to be effective for some specific condition.

See the following link for a complete list of all the US FDA Monographs.

And for more questions answered about OTC drugs, see this Q&A list from the FDA.

Being a cosmetic chemist can be frustrating. You’ll want to create products that can solve consumer’s problems but the reality is that you are handcuffed by one significant fact.

The most pressing cosmetic problems probably require drug solutions.

Hair problems

There are a number of problems with hair that are easily addressed by cosmeitcs but the most significant one, hair loss, is not. I just read this story about one of the latest discovery in hair loss research, a molecule that can turn off the production of Prostaglandin D2. It’s very interesting and offers a chance for curing baldness.

But you know what? If it worked, it wouldn’t be a cosmetic. It would be a drug.

This is not a solution that a cosmetic chemist could offer. Of course, your raw material vendors might have different ideas and will offer lots of things that affect hair growth (which don’t work either) but I digress.

What can a cosmetic chemist do about hair loss?

A couple of ideas come to mind.

1. Spray on hair. The current technology is pretty crude. A cosmetic chemist could make it better.

2. Artificial hair fibers. Can you make a product like this better?

This isn’t much, but it is something and I don’t see much work going on in these areas.

If you could develop a product that could be put on the head and made hair that looked natural and stayed in place, that would be an incredible breakthru.

There is a trend in the cosmetic industry some market research folks have labeled ‘beauty from within’. These are products which consumers are supposed to ingest to realize the benefit.

For example, BORBA Age Defying Skin Balance water.

In truth, I’ve been a bit skeptical of this trend. There is very limited data that suggests you can have a specific effect on skin by eating a certain product.

There certainly have been studies that show some foods have an effect on skin. For example, eating a diet rich in tomatoes has shown to protect skin from UV damage. But the conclusion of these is that there is only a small effect and you should still use standard sunscreens if you are going to be in the sun.

Here is a recent study that looked at the effect of what you eat has on your skin color. In this research, scientists found that you could indeed improve the appearance of your skin color by increasing the amount of fruits and vegetables that you eat. This is just preliminary research but it is interesting. It also coincides with an idea I had to see if I could turn my skin orange by eating enough carrots. I once ate 3 pounds in one evening but didn’t see any skin color change.

Cosmetic chemists ingredients

While I don’t find the current crop of ‘beauty from within’ products to be compelling (there’s little evidence that they work), research like these two do suggest that there may be something to this field of cosmetic development.

Perhaps, innovative cosmetic chemists will have to study up on nutrition and create some products that really are effective.

Are you familiar with Instructables.com? It’s a website where people share their methods for making different things. They have a number listings for different cosmetic products and most of the techniques that I found were not too good.

But I like this one for creating your own fragrance.

Make your own perfume

This moisturizer formula however…not so good.

How to make a basic moisturizer

Still, this is an interesting site and could provide you with some inspiration for making your next formulation.

Evaluating the Effectiveness of Cosmeceuticals

I saw this interesting review study about cosmeceuticals. The article goes through and looks at the best scientific evidence available for various cosmeceuticals including…

1. Retinoids
2. Kinetin
3. Niacinamide
4. Soy phospholipids
5. Green tea polyphenols

Their conclusion, all 5 of these cosmeceuticals fall short of the proof standards for efficacy as proposed by Albert Kligman (<–famous skin researcher). Of the 5 examined, only Niacinamide was closest to meeting the Kligman standards.  But that’s not what I wanted to discuss.  More important is how cosmeceuticals should be vetted for figuring out whether they are worth including in your formulations or not.

Kligman standards

Albert Kligman was one of the most famous skin researchers in the United States. He was also the guy who coined the term ‘cosmeceuticals’.

He also posed three questions that you should ask about any cosmeceutical product that claims a beneficial physiological effect.

Skin penetration

1. Can the active ingredient penetrate the stratum corneum (SC) and be delivered in a high enough concentration to have an effect on the target in skin?

If enough of the ingredient can’t penetrate the skin then it is not going to have an effect. This is where most cosmeceutical ingredients fail.

Theoretical effect

2. Does the active ingredient have a known specific biochemical mechansim of action in human skin cells?

It’s not enough to penetrate the skin. There has to be some specific known target that the cosmeceutical is going to affect. If not, the ingredient probably won’t have a noticeable effect. Things like fruit stem cells or natural extracts fail in this area.

Clinical proof

3. Are there peer reviewed, double-blind, placebo-controlled, statistically siginficant clincial trials to substantiate efficacy claims?

And here is where almost all cosmeceutical ingredients fail. Practically no one publishes or even conducts studies of this nature and magnitude. It is probably too expensive or too risky (in case the ingredient doesn’t work) to do so.

Cosmetic chemists and cosmeceuticals

As a cosmetic chemist, you need to remain skeptical of efficacy claims of ingredients and require your suppliers to have answers to each of these three questions. They probably won’t have the answers you seek but if you start asking, they may start conducting the studies.

Another installment of our Dissecting the Label series. In these blog posts we dissect a lable and discuss what each of the ingredients do in the formula and ponder why they are added. Last time we did a skin self-tanning prodcut. This time we’ll look at a hair conditioner. Organix Conditioner

Organix LOI

Here’s the ingredient list.

Aqua/Water/Eau (Water), Cetyl Alcohol, Behentrimonium Methosulfate, Parfum, Cetearyl Alcohol, Cetearyl Glucoside, Glyceryl Stearate, Glycerin, Cyclopentasiloxane, Dimethicone, Simmondsia Chinensis (Jojoba) Seed Oil (Jojoba), DMDM Hydantoin, Panthenol, Silk Amino Acids, Cocos Nucifera Extract (Coconut), Albumen, Cocos Nucifera Oil (Coconut), Hydrolyzed Milk Protein, Tocopheryl Acetate (Vitamin E) (Vitamin E), Tetrasodium EDTA, Methylchloroisothiazolinone, Methylisothiazolinone, Coumarin

The 1% Line

Our first challenge as a cosmetic chemist is to figure out where the 1% line might be. This can give us a clue as to what are the most important ingredients in the formula.

In this product there are two likely spots for the 1% line. Either right after the Behentrimonium Methosulfate or after the Dimethicone. My gut belief is that it is right after the Dimethicone. They certainly aren’t adding the jojoba oil at levels above 1%. I’m just a little surprised that the Parfum (Fragrance) would be used at a level above 1% but Cetearyl Alcohol most likely is so that’s what I’m going with.

You can see that figuring out this 1% line is not a precise science.

What the ingredients do

As always, we’ll group common ingredients and describe what they do.

Emulsion ingredients

These ingredients make the formula look and feel appealing.

Water – The solvent. Probably makes up 85-90% of this formula.
Cetyl Alcohol – Opacifying / emulsifier
Cetearyl Alcohol – Opacifying / emulsifier
Cetearyl Glucoside – Emulsifier
Glyceryl Stearate – Emulsifier

Conditioning ingredients

These are the things that make the formula work.  It’s why people use the product.

Behentrimonium Methosulfate – Hair conditioning. For anti-static, detangling. Makes hair easier to comb.
Dimethicone – Hair conditioning for shine & slickness
Cyclopentasiloxane – Hair conditioning
Glycerin – Some moisturizing effect but likely rinses down the drain.

Claims & Puffery ingredients

These ingredients are added to make the product sound more appealing.  If these raw materials were left out of the formula, it is unlikely that anyone would notice a difference in performance.

Simmondsia Chinensis (Jojoba) Seed Oil
Panthenol – Some evidence this could effect hair but I remain skeptical
Silk Amino Acids
Cocos Nucifera Extract (Coconut)
Albumen
Cocos Nucifera Oil (Coconut)
Hydrolyzed Milk Protein
Tocopheryl Acetate (Vitamin E)
Coumarin

Preservative system

Since microbes can grow in the environment created in this formula, preservatives have to be added to ensure they don’t.  This conditioner uses two classic preservatives that have a broad spectrum of organisms that they will kill.

DMDM Hydantoin – Preservative
Tetrasodium EDTA – Helps to losen cell walls & make preservatives more effective.
Methylchloroisothiazolinone – Preservative
Methylisothiazolinone – Preservative

Fragrance

Parfum – In US this should be labeled Fragrance.

This is a pretty standard conditioner formula with lots of claims ingredients added to give the Marketing department something to talk about. Using both silicones and a cationic surfactant is a good idea as it provides a nice effect that the ingredients separately can’t achieve. Overall, a nice formula.

We received this question here at Chemists Corner central and thought it would be a good one to write an article about.

“Why do the raw material suppliers recommend the combination of presevatives versus using them alone…..for ex: why do the manufacturers recommend a combination of sodium benzoate and potassium sorbate rather than using them individually….

Why you put preservatives in cosmetics

With all the bad press about chemicals used to preserve cosmetics you might wonder why companies don’t just stop using preservatives.  Well, the reason is that cosmetics that contain preservatives are safer than ones that don’t contain preservatives.  This is because disease-causing microorganisms can multiply at exponential rates in cosmetics if there are no chemicals in there to stop them.

And if the consumer is putting a dollop of microbe laden skin lotion on their body, they are bound to contract a disease.  It is just not smart to use unpreserved cosmetics.

The other reason to include preservatives is that when microbes grow in your cosmetic product they can produce foul smelling odors and strange colors.  Consumers just aesthetically do not want to use bacterial contaminated products.  It’s a bit like the same reason people don’t want to eat moldy bread.

What do preservatives do

Cosmetic formulas have all the key factors needed for microbial growth including water, nutrients, and energy.  At a suitable pH and temperature, it will be like a microbial cocktail party.  Preservatives stop growth by killing cells and spores (usually by disrupting cell membranes) or by making the system hostile to growth.  See this article for more about cosmetic preservatives.

Why you need multiple preservatives

So that brings us to the question that started it all, why use multiple cosmetic preservatives?  Basically it’s because some single preservatives do not kill a big enough range of microorganisms.  As a cosmetic formulator you need to ensure that your preservative system will kill any bacterial, mold, or fungi that the formula might encounter.  Since you don’t know what will be encountered you have to plan for every possibility (or at least as many as you can).

There are some preservatives that are able to kill a wide range of microbes (e.g. Alcohol, Parabens, Formaldehyde donors).  That is why these ingredients are so popular with formulators.  Other ingredients like Sodium Benzoate or Potassium Sorbate are only effective against certain types of microbes.  They are more active against yeasts and molds but have a lower activity against bacteria.    One way to compensate for the ineffectiveness of one compound is to include another compound that has the ability to kill other organisms.  By combining preservatives, you increase the spectrum of microbes that your formula can withstand.

Of course, if you used parabens and formaldehyde donors you could be more confident in the effectiveness of your preservative system.  However, for marketing reasons these compounds must be avoided.  It makes your job as a cosmetic formulator a bit harder.

This is a guest post by Gary Neudahl.

In personal care, there are cosmetics and there are toiletries. What’s the difference? In general, a cosmetic is intended to beautify the body; a toiletry is intended to care for the body. Among toiletries, let’s take a look at Antiperspirant Deodorants (APDOs in industry shorthand) sticks.

APDOs are made with an astringent substance (typically an acidic aluminum-based salt) that, when applied to the underarms, reduces perspiration and concurrently inhibits microbial growth for reduced malodor generation. Sticks, gels, soft solids, roll-ons, pads and sprays are typical product forms. They are usually scented for additional malodor protection.

APDO stick formula

Here’s the typical composition of an APDO stick:

Ingredients

The most commonly used volatile carrier is Cyclopentasiloxane, a cyclic silicone fluid that evaporates about one-sixth as rapidly as water, with virtually no cooling effect due to its low heat of vaporization.

The typical co-gellant is Stearyl Alcohol, with a specific chainlength distribution (mainly C18) that inhibits stick crystallinity.

A commonly employed active ingredient is Aluminum Zirconium Tetrachlorohydrex Gly, which provides good efficacy.

Nonvolatile carriers, which contribute to product skin feel and also reduce or prevent a whitening effect on skin, may include mineral oil, vegetable oils, and/or esters.

The most commonly used gellant is Hydrogenated Castor Oil. It is not fully hydrogenated (to convert unsaturated Ricinoleic Acid moieties to saturated Hydroxystearic Acid moieties), both to control melt point and further inhibit crystallinity. Due to its residual unsaturated content, antioxidants may be added to extend shelf life.

An emulsifier and/or solubilizer may be used to help incorporate the fragrance and to extend shelf life. It also helps with removal of the product from skin during cleansing and from clothing during laundering. PEG-8 Distearate is such an emulsifier that is commonly used in APDO stick formulations.

Feel modifiers include particulates such as corn starches and talc, which are added to improve product aesthetics during and after application.

What about “label copy” ingredients? They are ingredients that are added for marketing- rather than performance- based purposes, to increase the likelihood of consumer trial and satisfaction. They are among the hooks that snare consumer interest, although product performance, and scent, are what determine repurchase intent.