[JulietK]

Thank you Perry! 

Er… I already did lol  :#

[JulietK]

@Bobzchemist thank you again.

Elastomer: a copolymer or a cross-polymer, like Silsoft Silicone Gel for example? I have just bought some silicone gel (Cyclopentasiloxane (and) Dimethicone/Vinyl Dimethicone Crosspolymer). Would that be useful?
And by “difficult to fill”, do you mean with… what? 

I have some stuff already, including silicones and some film-forming agents, and I’ll soon get my hands on products like Antaron WP-66, DC 556 fluid, Xiameter PMX-3031, and KOBO treated pigments.

As for suppliers, I’m pleased to see that even suppliers who generally only deal with professionals are sometimes ready to sell small quantities.

If you have a potential list of ingredients which would be useful for me, I’m all ears o:) 

[JulietK]

   

[JulietK]

@Belassi you inverted your letters, didn’t you?

I guess a good reason for making W/O emulsions would be producing very effective skin-barrier creams, for instance.

[JulietK]

Thank you so much @Bill_Toge .

[JulietK]

@mcars

Maybe what you mean is zinc oxide?
Or titanium dioxide?

[JulietK]

@johnb

thank you for answering. I’ll have a closer look, and try and see what I’m missing.

@Bobzchemist
thanks again. I’m actually looking for some treated KOBO pigments, which would make my life a lot easier.
My main goal is to obtain a usable product. Are there easier ways you would think of? You’re welcome to suggest anything that will make my task less complicated.

[JulietK]

Hi @Bobzchemist, hi @johnb

Thank you both for your answers.

Bob, you’re right, I had forgotten polysorbate-20! Thank you so much for providing the additional information, it really helped figure out this thing.
I know I don’t have lots of chances to succeed, but I’ll try. Maybe 12,000 rpm will suffice… maybe not. I’ll do my best.

I like your ideas about the volatile silicone. My guess is that this foundation contains both low-density (5 cPs? Who knows) and medium-density dimethicone (maybe 200 cPs or more). I think I’ll try and use both, adding the volatile portion at less than 50°C.

John, I mentioned steric hindrance because during my research I had come across this:

“It is probably not an accident that all the effective dispersants which operate  by steric hindrance are either liquids or extremely soft solids like stearic acid.”

https://books.google.it/books?id=O-rcBwAAQBAJ&pg=PA36&lpg=PA36&dq=%22stearic+acid%22+%22steric+hindrance%22&source=bl&ots=sFDbjDzO5u&sig=T5cFzJkguugiFbImQEcflZ0bWmo&hl=it&sa=X&ved=0ahUKEwiEpc22xuLSAhUD1iwKHX_gDDEQ6AEIMDAB#v=onepage&q=%22stearic%20acid%22%20&f=false (p. 238)

Maybe the author is wrong, my competences are too low to even try an assessment, I just trusted the book. This looks like a minor question by the way, at least at the current stage of my experiments.

I’ll go ahead and experiment more, based on an O/W emulsion hypothesis. I’ll come back to relate as soon as I’m done.

Thank you again for your help, it’s precious. I truly appreciate.

[JulietK]

Hallo @johnb,

I did some research based on your first intervention (O/W emulsion).

My current understanding is that the emulsifying system in this foundation could be the following:
- Lameform TGI (emulsifier)
- stearic acid (emulsifier, increases the steric hindrance)
- cetyl alcohol (co-emulsifier, increases the steric hindrance as well)
- TEA (used to neutralize stearic acid -> result = surfactant).

I’m wondering whether you or someone else can confirm, or contradict, my findings.
If not, thank you all for helping me.

[JulietK]

Sorry for this small OT. (Partially) quoting John, I would stay away from potassium sorbate and sodium benzoate. They are becoming quite “popular” for causing contact dermatitis.

[JulietK]

Mmmmh, I’m thinking. Hard.

Let’s see… what if this emulsion was held together mainly by means of thickeners and stabilizers? Is this possible? What if stearic acid played a role in this, along with Xanthan Gum, MAS, and the film-forming agents listed?

From the heights of my complete inexperience, I think you’re right about the Ultra Turrax or similar. Not only for the droplets size, but also for optimal pigment dispersion. In fact, I can’t see any coated pigments in the list (unless they are dimethicone-treated, and the two ingredients are listed separately, which all in all doesn’t seem probable to me).

EDIT Oh and wait! It it’s a W/O, why did the water-soluble dye dissolve?

I’ll have to run the electricity test : ))

Thanks again for your time, Bill. It’s a pleasure to have so much advice in such a short time. Beautiful forum!!

[JulietK]

Hi Bill, 

thanks for coming in to help. The reasons you stated are the very same which led me to change route and start thinking that this could be a W/O.

BUT: Lameform TGI is also an O/W surfactant. It actually seems to be quite an interesting guy… I guess they chose it for its skills in pigment dispersion.

Plus, if this was really a W/O emulsion, shouldn’t there be electrolytes? I can’t see any, though probably this is just my ignorance playing games with me.

[JulietK]

Unfortunately, I don’t : (
But a home-made device should work just as well and it doesn’t look too hard to build one, so as soon as I have some spare time I’ll do this!

Anyway… dye test positive, dilution test positive… I guess this is really an O/W emulsion. Or to be more precise, a Si/W one.
I don’t care if it’s a W/Si/W, since I wouldn’t be able to reproduce it anyway, so I’ll just stick to Si/W.

[JulietK]

Hi Jeremien (maybe Jérémien? : ))

Thank you for offering your advice. This formulation definitely looks tricky…
By the way, I guess polysorbate-20 is present just in traces here; it’s waaay down in the LOI, and I imagine it could be anywhere between 0,05 and 0,5g. If I’m right on the percentage, would it still be able to exert notable influence on the HLB?

I’ve been thinking about measuring conductivity since last night. Not quite sure how to proceed though, since I should build something on my own. I’ll try and see whether a couple of wires, some batteries and a small soldering iron can do the trick.

Thanks again for your help : )

[JulietK]

Mmmh why wouldn’t Xanthan Gum and MAS work nicely in a W/O? Gums can improve a W/O spreadability, MAS is a great suspending agent for pigments, and both can stabilize and thicken the water phase, as far as I know. What am I missing? 

As for TEA, I thought it was just a pH regulator here, but it sounds like I might be off track, so I’m counting on you to correct me on this one as well.

Thank you for the eBook (downloaded!) and for your tip. Here are my results.

- I took a powder dye that I assumed is hydrosoluble. Just to be sure, I put it in two separate containers, one with oil, the other with water. In oil, one can now see the small dye particles, in water it dissolved immediately. OK.

- I then took the product and did the same. I added a fourth container with an O/W cream, to act as a control unit (lol). In the cream, the dye quickly started dissolving; not really so in the foundation, but after a little stirring I now have rose-coloured foundation.

What can we infer, in your opinion?

Thanks again for your kind support John : )

[JulietK]

Thank you very much John : )

[JulietK]

Hallo John,

thank you for taking the time to comment my post.
I’ve been making creams, serums, gels etc. for a little while now, so this foundation is not my very first step.
I should have said that! (Actually I was giving it for granted, for the reasons you just stated.)

As for the ingredients, I think I’m getting at it; some stuff is not available to small consumers, but maybe a few substitutions will do.

My real concern was the kind of emulsion. I’m on my 13th take on this foundation, nearly all my experiments look sufficiently stable (fingers crossed) though of course the final result is still far from satisfactory.

What I truly need at this stage is some experts’ advice about the phase relationship.
I personally don’t think that the position of water alone can be conclusive - technically speaking, this could very well be a W/O with a very high content in water. Or a W/O/W. Hence my request : )

If I said something silly, you’re welcome to correct me, and thank you in advance!

[JulietK]

Hi guys (and girls!), Giunia speaking.
Thank you so much for accepting my membership. I truly admire your work and your way of helping people around the world.

I’m Italian, a philologist and an academic researcher as well as a freelance translator. I’m deeply interested in cosmetics and formulation - but I’ve only just started, so there’s a huge amount of things to learn. 

I’m currently trying to reproduce a liquid foundation, so my questions will probably concern that topic, at least at the beginning.

See you soon : )