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It surprises me that Unilever invested in them, who you would think would like to do things as kosher as possible.

I like the idea of 3rd party efficacy trials though, but here they’re not even disclosing who the 3rd party is. Consumerreport did something similar for acne treatments in 2011 http://www.consumerreports.org/cro/2011/11/review-of-acne-treatments/index.htm

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@Alias Thanks for the update, exciting stuff, could set precedence for other cases of mislabeling. I’d be worried about would be a counter suit for libel if you “blogged” about it, so going to the FDA seems like a safer route.

In any case, I hope you take some kind of action and let us know

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Phenol peels? lol

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@Christopher

I have the same experience as naturalchemist - Olivem in my silane coated zinc oxide sunscreen formula was much more stable. I haven’t experienced any whitening effect from it either, but it needs slow mixing during cooldown after the initial emulsification to re-form a liquid crystal structure which in sunscreen applications is important. This can take 20+ minutes according to one study.

There are also other liquid crystal emulsifiers like Monatov 68, but it my application it was also less stable than Olivem.

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Digging this one up.

I just tried to use BTMS for the first time, all was fine until I added DL Panthenol in the cooldown phase; instant curdle. Perhaps it holds negative charge.

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But fat’s could plausibly also help remove makeup, devil is in the details. Curious if anyone has experience with this concept and if it’s legit.

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Yeah, could be that they’re just not on this forum as much, seems like about 2x more men than women use forums http://www.pewinternet.org/2015/08/19/mobile-messaging-and-social-media-2015/2015-08-19_social-media-update_04/

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@Belassi, our new? Never heard of that brand

@Perry i have a sneaking suspicion that most cosmetic chemists are men and most men don’t moisturize.

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@Belassi surprised by the high amount! Did you find 10% necessary to make it adequately moisturizing? it might be the same as as http://www.lotioncrafter.com/lotioncrafter-el61.html (they often just repackage things from DOW et al) which i happen to have.

Do you have a link to the formula? google ain’t helpin

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@Belassi thanks, why this specific silicone/polymer? What use rate would you suggest to see significant TEWL reduction?

Thanks for the buffering / Geoguard tips, also Bill_Toge is right and I think there’s a very good chance it’ll pass.

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Microchem in the US charges $350.

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QACS in greece does USP51 for $150/formula, they need 150g.

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I should add it’s otherwise a pretty normal OIW emulsion.

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not quite at this scale yet

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@Bobzchemist I see. I was referring to the cooling, but you’re saying paddle and anchor impellers perform similarly on the sub 200 kg scale?

I tried the new impeller at 400 rpm, and what I got adding the oil to the water phase was some gelling under 50C for it to revert to liquid again under 40C. Maybe gelling can be prevented with 200 rpm stirring, or maybe it’s not preventable with this formula and maybe it doesn’t matter.

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Thanks for the thoughtful replies

I decided to design and 3D print my own anchor impeller last night in ABS plastic, which I believe should work fine for sample making with most formulas. It definitely works well and looks pretty funky in bright orange.

50 mm diameter, 50 mm tall, for 8 mm shaft with bolt on end.
Freecad file: http://www.filedropper.com/50mmabsimpeller2
STL file for printing: http://www.filedropper.com/impeller10001

@MarkBroussard  I’m not sure that’s true, it’s a small oil phase and the formula is stable for 1 month at 45C, but I can always give it a shot, just concerned it’ll ruin the watery skin feel. I previously went down from 4% Olivem to improve sensory properties. But could give it another shot going up to 6%.

@Bobzchemist good to know about scaling up! When would you go paddle over anchor? They also have a 50mm anchor which would be perfect for small scale 250ml samples.

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Did you consider naming said competitors here if you want to be on the side of transparency and truth? People could find this post through Google, the blog is well indexed.

Why didn’t you get the lab results published in a high traffic and trustworthy (vegan) blog? Heck maybe you could even offer to do a roundup for consumer-review using third party labs? You have the evidence and people should know!

This issue is widespread and goes beyond cosmetics, huge problem on Amazon in the US for instance where you have companies peddling vitamin C serums with Vitamin C derivatives that don’t convert to ascorbic acid in the skin.

Lastly, have you recently asked all your suppliers? And if the answers are all negative, thought of hiring chemists or whom have you to invent new naturally derived dyes? If you have the resources that could be a big fat patent.

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@johnb no it does, zinc oxide will raise pH towards 7 and it’s worth pointing out as the goal was to lower pH of the formula and nobody had mentioned this.

Otherwise I was aware it was an old thread, but threads here serve as useful resources for others who find them through google (as I did) and work as wiki pages in a sense.

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@johnb think you’re reading a bit too much into my response. I was grateful for your reply, let me elaborate.

“It depends what’s important to you”; different companies and formulators have different goals with formulas. Some are OK with lower SPF ratings, others are not. Also in some markets in vitro performance may be paramount and a better benchmark of actual UV protection knowing that in vivo tests can be manipulated with anti inflammatories. Personally I’d really like to get SPF25-30 out of 10% ZnO if possible, but I’m not concerned getting it higher than that.

Thanks for pointing out what Elta MD uses. For the other people reading this thread i also pointed out that Phenoxyethanol and Ethylhexylglycerin is commonly used.

I have one Phd derm graduate working with me, the other link was BY a Phd chemist and a good blog post exploration, of course, having a degree in itself doesn’t necessarily mean anything, but the post holds its own imo. Personally I decided to get out of academia after a measly BSc

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@john certainly important for your SPF rating. it really depends what’s important to you.

Phenoxyethanol and Ethylhexylglycerin is also commonly used. 

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@Bill_Toge AFAIK the reduced efficacy has only been demonstrated in vivo, so it’s possible that the physical in vitro SPF rating stays the same but that the addition of the acid does sensitize to some extent making erythema more likely and hence giving lower in vivo SPF results. Or maybe it’s a bit of both. 

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It’s definitely your 2% Zinc Oxide that raises pH, but it will also protects against AHA induced photosensitivity at a ~1:1 ratio.

I agree with @Bobzchemist s strategy of building your formula from the ground up, particularly if you’re having stability issues.

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Reconsidering i’m going to go with a lower amount, will test 2% l-lactic acid for a slight reduction in pH (the original pH 7 is fine and optimal for ZnO stability to avoid the potential for excessive ZnO ionization).

At 7% you could still feel a slight at pH 5 - not what you want. Now what are good options for gentle preservatives happy at pH 6-7?

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@johnb yes, I’m running accelerated stability right now, but all seems fine likely due to the silane coating. I see brands like Elta MD use ~1% lactic acid.

@Bill_Toge free uncoated zinc ions that increase pH have to be counterbalanced AFAIK. No other basic components in the formula. Most if not all mineral only sunscreens are pH ~7, most organic sunscreens are pH 5 from my experience.

Had a Phd in dermatology help me do some digging, and CIR has an answer to this question based on a few small studies:

The Expert Panel compared the increase in the number of SBCs associated with AHA pretreatment to SBCs produced as a
function of increased UV exposure alone. AHA pretreatment caused less of an increase than did raising the UV exposure to
1.56 MED. The increase in UVR damage associated with AHA pretreatment was of such a magnitude that it is easily
conceivable that aspects of cosmetic product formulation could eliminate the effect. For example, inclusion of a sunscreen
with an SPF of 2 would eliminate the effect. Likewise, addition of color additives or vehicles that produce even a small
increase in UVR reflectance would eliminate the effect.

CIR 2013 “Safety Assessment of
Alpha Hydroxy Acids
as Used in Cosmetics” http://www.cir-safety.org/sites/default/files/ahas.pdf

It should be fine, but there might be a decrease in SPF factor which you’d have to to in vivo tests to find.

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Thanks John, good point, judging from the ingredients this doesn’t seem to be much of an encapsulation, just a droplet dispersion.