Bobzchemist
Forum Replies Created
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Making stable liposomes pretty much requires one of these:
or something similar -
Quick-and-dirty evaluations can be done with a small centrifuge, but there’s not a perfect correlation - you still need to run the stability tests.
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Yay Matt! Awesome answers, especially on the lecithin.
Once you decide to use any silicone in your formula, you have permanently destroyed any possibility of calling it natural. As a result, there’s no real reason to use lecithin as an emulsifier, although if you had to (cough-marketing requirement-cough) either something like Lecigel, or using the other emulsifiers Matt recommended and lecithin at fairy-dust quantities, would be the only ways to get a successful emulsion. -
No, it’s just a question with a very long answer.
The CTFA once wrote a monograph on this subject. A quick search turned this up:If you do a search on “evaluate the stability of cosmetic emulsions” you should get more information. -
Shouldn’t be an issue, but you’ll have to test to be certain. There is nothing intrinsic about cetyl alcohol that would cause it to initially react badly with lecithin and/or lecithin derivatives.
The thing you will have to check for experimentally is whether or not the wax-type structure cetyl alcohol slowly forms at room temperature will disrupt the lamellar O/W emulsions formed by the lecithin emulsifier systems. I’d be very interested in seeing your results.If you wanted to write this up, you could probably get a publishable paper out of these experiments. -
Viscosity and suspendability are two different things. Without something to suspend them. pigments will prove that gravity works by settling out and breaking your emulsion in the process.
If you look up formula’s for liquid foundations, you should get some ideas.
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Viscosity and suspendability are two different things. Without something to suspend them. pigments will prove that gravity works by settling out and breaking your emulsion in the process.
If you look up formula’s for liquid foundations, you should get some ideas. -
All pigments (as opposed to dyes) become more intense as their apparent particle size decreases. Most, if not all, pigments agglomerate/re-agglomerate, though, so taking a shortcut by buying finely milled dry pigment is usually not cost effective. Increasing the strength and/or length of time for your milling process will yield more intense color. There are dispersing aids that will reduce the amount of time/effort this takes.
Once you have milled your pigments to the point that additional milling does not intensify color, though, your only choice to increase intensity on skin is to increase the amount of your pigment that’s applied to the skin.You can do this in one of two ways:1) Increase the amount of pigment in the formula2) Change the payoff, i.e. the amount of product that is applied to the skin during a typical application.How to change the payoff of a stick formula is something that you’re going to need to learn either through trial and error formulating work, or through consulting with suppliers and/or consulting cosmetic chemists. This is not information that will come for free - you’ll either need to put in the lab time to figure out your formula’s performance, or pay someone who’s already taken that time to figure it out for you.I’d be happy to recommend a couple of consultants if you want to go that route. -
Have you looked at the home crafting sites?
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Looks like Kumar Organic Products has it:
and MakingCosmetics has it as part of a mixture: -
Have you tried running the machine as slowly as possible?
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Just offhand, that’s only a 4 gallon batch. Making it and then filling 1000 pieces entirely by hand with a syringe shouldn’t take more than 30 hours or so. Why not make it in the lab and just hire a temp to fill it? Or are you not FDA registered?
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Less salt would have worked too. Just sayin…
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Even in a thick w/o emulsion, especially if all the viscosity is coming from the water phase concentration, using only a thin base oil to carry your pigments is an invitation to instability as the pigments prove that gravity works by setting out and breaking the emulsion in the process.
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what is suspending your pigments?
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This is the best I’ve seen:
On the other hand, this one is closer to industrial mills: -
Amazon’s, but they are all similar:
and you need a piece of frosted plate glass for a base -
Amazon’s, but they are all similar:
and you need a piece of frosted plate glass for a base -
As I’ve said before on here, a hand muller can be used if you can’t afford a three-roll mill. Sometimes a kitchen blender will also work.
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I’d bet a weeks pay that you didn’t use any pre-made color dispersions. As pigments ‘wet out’ their color gets more intense. It can take a day or two for the color to fully develop if your mixing isn’t strong enough…
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Can you use a sealing disk for your jars? It’s a fairly common solution to this problem, so they should be easy to source.
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In the US, skin lightening products are FDA regulated pharmaceuticals. Since you’re not a professional, it’s just too legally risky to give you any advice, sorry.
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Google is your friend…
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Are you a chemist?
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Stearic acid must be neutralized for stability.