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Is there any way to change the topic title btw? would be useful to mark it as resolved

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So I found the culprit, >50 kDa Hyaluronic Acid, in the emulsion it becomes weirdly stringy and I doubt much or any of it penetrates the skin.

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Thanks to you both!

@Bobzchemist I’ve requested a sample and pricing info of Ganex, do you know any other popular alternatives? I’m using a high % of squalane which is strongly absorbed, yet that alone doesn’t seem adequate to provide long lasting coverage.

@laskedbetter I can try Isododecane and see if that improves things. Also could Cyclo-Dimethicone work as an alternative to D5 (as it’s available at makingcosmetics)? 
BTW Shin-Etsu has a Trimethylsiloxysilicate (and) Isododecane blend for sale.

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Available in say less than 1 kg quantities.

Any of those options you think would work better or are you suggesting I try them all?

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long wear, conceals for a long time, ideally available off the shelf and compatible with an oil based formula. I’m sure some options are better than others for this kind of product?

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I have used the Now Foods powder Bobz refers to and it does indeed form a gel, different in texture than both xanthan and carbomer though, more “stringy”.

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Ah, the end of Aloe Vera Water is near. 

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So I got a similar effect with a new formula using a different emulsification system (ewax), which I think makes it reasonable to exclude lecithin or lanolin as causes. The commonalities that could be causative unique to these two formulas:

Squalene 5%
Retinol 0.1%
Ceramide Complex from Makingcosmetics (Ceramide 3, ceramide 6 II, ceramide 1, phytosphingosine, cholesterol, sodium lauroyl lactylate, carbomer, xanthan gum)
Hyaluronic Acid 0.5% ~10kDa

They could only cause problems in combinations with other ingredients, so testing them alone might not work. Thoughts?

 

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Well, it is a little suspicious that the MSDS still says 1%. Long term stability is not currently an important goal.

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Propylene Glycol can be found as food grade and is used in certain foods/supplements, it’s metabolized into pyruvic acid, acetic acid, lactic acid and propionaldehyde.

Now question is, what does 1,3-Propenediol metabolize to? One study suggests, 3-hydroxypropionaldehyde, malondialdehyde, or 3-hydroxypropionic acid, malonic semi-aldehyde, malonic acid, and ultimately, carbon dioxide and water. https://www.federalregister.gov/articles/2013/06/12/2013-13823/13-propanediol-exemptions-from-the-requirement-of-a-tolerance

So it could very well be that 1,3-Propanediol is relatively less safe than Propylene Glycol (albeit probably not at levels that matter for skin care applications). Something to consider.

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Not originally, figure It’s not necessary for my formulation. 

Just heard back from Makingcosmetics btw, they say that 5% is correct, not 1% and they’ve updated their listing

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Possibly, I’m not sure it’s better or worse than using regular retinol, but it’s quite expensive: if using the IU value they give at 17000IU per gram, then it’s 5% concentrated. 33.6 oz would contain 48.5 grams Retinol. If using their activity measure of 1% retinol, then we’re down to 10 grams!

1 oz of product with 0.5% retinol would require 0.15 gram retinol, 48.5 gram would be enough for 323 units so the cost of the retinol alone would be $1.7/unit. If going by their activity measure then it’s $8.5/unit and that gets prohibitively expensive!

Wheres buying 1 kg retinol in polysorbate-20 for $1500 would give you a per unit cost of $0.45.

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Thanks @Bobzchemist had a feeling you’d chime in on this one (and happy chemistscorner ranks high on google, so many others with the same question are likely to find this thread).

In lieu of a Jetpulverizer or proprietary shaped particles, these are the options I’ve found readily available in stores, so in this case makingcosmetics or possibly soap goods could be good choices with relatively low particle sizes?

barmbleberry: doesn’t list particle size
bulkapothecary: doesn’t list particle size
essentialwholesale: 263 - 1233 nm

makingcosmetics: 200 - 250 nm
newdirectionsaromatic: 325 nm mesh size

soapgoods: > 100 nm (USP)

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Looks like I’m not the first to ask this questons:

http://swiftcraftymonkey.blogspot.com/2009/07/cetyl-alcohol-vs-stearic-acid.html

Seems like the only conclusion I can find is that stearic acid creates a lotion with more drag, good for e.g. foot creams, wheareas cetyl alcohol provides more glide. 

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It is what i mean, if that causes visible tightening over say 12 hours.

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@Michellereece

Wow

“A skin protectant drug product containing cod liver oil as an active ingredient also must include mineral oil (tj 347.10(e)). In addition, a skin protectant drug product containing cod liver oil must be labeled so that the quantity used in a 24-hour period does not exceed 10,000 USP units of

vitamin A and 400 USP units of vitamin D (cholecalciferol). A skin protectant drug product can

contain colloidal oatmeal at a minimum of 0.007 percent or mineral oil at a minimum of 50 to

100 percent as single active ingredients. However, a skin protectant drug product containing

both colloidal oatmeal and mineral oil must include a minimum of 0.003 percent colloidal

oatmeal and 30 to 35 percent mineral oil (5 347.10). “
http://www.fda.gov/OHRMS/DOCKETS/98fr/FDA-2008-N-0387-gdl.pdf

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Good point re endemic vs temp, I wonder how the demographic is though, how often is hyperpigmentation caused by one time exposure vs how much is chronic (either from internal or external causes).

I’d rather add 0.5% retinol than rely on shea, but I like its skin feel, yet not sure its superior to coconut oil for this purpose - quite different fatty acid compositions.

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But it doesn’t actually have any positive effects beyond that?

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Yet do you really believe that applying a lotion daily is a cure? To me that’s still a temporary patch, and wouldn’t you be concerned that if you start feeding the skin from the outside, that it won’t be able to feed itself as well in the future - something to at least consider.
And why not combine occlusives, which could act as a band aid letting the skin heal, and nourishing ingredients? 

How much retinol does shea have btw? Do you think refined differs from unrefined? 

Chia oil seems interesting, I’ll order a sample

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Interesting, what do you mean when you say “couple”? I can get samples of the ones you suggested, any reasons one would be better than the other? Don’t know much about silicones.

Dow Corning 2503 Cosmetic Wax (Stearyl Dimethicone and Octadecene)
Dow Corning Silky Wax 10 (Stearoxytrimethyl silane and Stearyl Alcohol)
Silwax D221M (Cetyl/Hexacosyl Dimethicone)

The issue with these is that the MOQ is 13kg, enough material for > 10000 2 oz units used at 2%, not ideal when just starting out. Are there other options with smaller MOQs? Ideally available “off the shelf”.

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Some other ingredients I’ve seen used vs eczema, not specifically to reduce TEWL:

Alpha Lipoic Acid

Benzoin oleoresin

Calamine - Anti itch FDA approved

Camellia Sinensis Leaf Extract

Ceramide 3, Ceramide 6 II, Ceramide 1, Phytosphingosine, Cholesterol

Cholecalciferol

Cholesterol

Colloidal Oatmeal

Colloidal Sulfur

Cyanocobalamin

Emu Oil

Glycine

L-Proline

L-Taurine

Magnesium Ascorbyl Phosphate

Magnesium Sulfate Licorice (Glycyrrhiza Glabra) Extract

Menthol - Anti itch FDA approved

Methylsulfonylmethane

N Acetyl L Cysteine

Niacinamide

Retinol

Silymarin from Milk Thistle Extract

Sodium PCA

Zinc Sulfate

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I find Sepiplus to work extremely well as an emulsifier in a emulsion containing benzoyl peroxide, where emulsifying wax nf wasn’t stable enough. Rub in is comparably good too.

Any potential caveats?

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Wow, now that’s detailed knowledge! Neither the supplier Lotioncrafter or Seppic US knew.

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Thanks Bobz.

This reflects my experience, useful to know about the production scheduler as well, it often helps is you speak the same language. 

And it is also my experience that larger companies charge more per unit, even at the same quantities.

My question is also one of etiquette, if you have questions critical to manufacturing, e.g. what kind of roll your label goes one, how often should you ping about your question? Hard to judge, seems every two days is reasonable.

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@Bobzchemist yes that was more what I was getting at, not the exact amount of days that’s reasonable, but when it’s reasonable to get A deadline/lead time and how often to contact your manufacturer if you have questions etc.