[doctorbrenda]

Thanks!  I’m glad to know that my guess was right.

But that is so interesting that the required HLB could be different based on whether you’re making an o-in-w or w-in-o formula.  I wish the manufacturers and suppliers that stated that difference before.  Whenever I am calculating an HLB for an experimental formula, whatever number it reveals will then lead me to choose whichever emulsifier (or blend of emulsifiers) that get as close as possible to that number.  Some people would say you can easily be off by +or-1, but I aim to get it as close to .5 in either direction… but I didn’t think that the requirement for the same exact ingredient would change when in translates into a water-in-oil emulsion.  I understood that it’s NOT simply the amount of water you have in emulsion, but rather the type of emulsifiers you choose that would determine the nature of your “Hydrophilic-Lipophilic Balance” requirements.  Although generally if it’s more than 50% water, I think it would be difficult to successfully make it an o/w emulsion.  I’ll have to integrate that information when re-formulating.  Thanks for sharing.

[doctorbrenda]

I would not recommend a Brita water filter for this task.  There are some good options on Ebay as someone noted above.  I have colleagues that have used them with great success, and some are reasonably affordable.

[doctorbrenda]

I agree.  If they aren’t following proper INCI labeling, or any other real regulations, then it’s a waste of time to even try to speculate.  Unfortunately there are many cosmetic companies that are trying to market their products as “natural” and “organic” just to appeal to uneducated consumers concerns about environmental toxins, carcinogenic substances, or other adverse effects.  Buyer beware.

[doctorbrenda]

Wow!  Okay people, I think this is what happens far too often with text/internet communication…. to much opportunity for misinterpretation.

Perry, thank you for your mature, professional, respectful response.  I’ll just ignore some of the other more dramatic, sarcastic responses.

What I really should have done is just posted 3 formulas that are almost identical, with only differences in emulsifier blends, concentration levels, etc… for the sole PURPOSE of discussing quality and textural differences, and how they interact with each other, etc.  That’s where I was really hoping to go with this (not where it ended up going).  I guess this is not the place, nor the people with which, to have those conversations.

With that said, I did get some really good answers from two different cosmetic pharmacists - so my question was valid, but the answers are more complicated than what could be reasonably discussed in this forum.  They gave me some very different information (in fact, in complete contrast) from what I’ve read on this website, but I don’t want to offend anyone by posting it, because I’m sure some will find that type of expert feedback to be “invalid” or something that should be “dismissed” or “ignored”, etc., and that’s not going to lead to a forum of progressive learning, sharing experiences, and co-education.

And no worries John, everyone likes the formulas I’ve created… it’s just me that wants to fine-tune them, and always trying to improve things…. being perfectionistic can be more work than it’s worth sometimes.

[doctorbrenda]

I can see that what I really need to do is spend more time writing a longer explanation before asking a question.  I think everything was posted here is well understood by formulators.  I did not say the formulas in question only contained “3 ingredients (oil, water, emulsifier)”.  The reason I kept referring to it as the “Lipid” phase is because anything there are many different substances that fall into that general category, including but not limited to wax esters, siloxanes, fatty acids, phytosterols, triglycerides, monoglycerides, all vegetable oils and butters, fatty alcohol waxes, and of course there are solvents and humectants as well, but since they are water soluble, it is not considered a lipid that needs to be emulsified in the “Lipid” phase.  Emollients are usually substances that also need to be emulsified with water, and therefore fall into the category of the lipid phase.  I don’t think most people are calling it the “oil” phase anymore, at least not when they understand that there are so many other substances that need to emulsified in order to mix with water.  I cannot believe I need to explain this in order to correct a misunderstanding.

Anyway, moving on, I think it is also well understood that manufacturers have a general guideline as to the concentration (like 2% to 6% of substance A, or 3% to 10% of substance B, etc.)…. but whether you use the minimum or maximum that is “recommended”, which is just a suggestion not a requirement, ALL DEPENDS on HOW MUCH and WHAT TYPE of substances that you are emulsifying.

If you use too little, no matter great you think the rest of your formulation was calculated (including the required HLB), it will most definitely fail.  I have NEVER had a problem with a failed emulsion, probably because I studied up on this stuff for three years before ever running a single experiment, so I had a good enough base of knowledge.

So the reason I did not write ANYTHING about calculating the required HLB for any formula is because I thought that would be naturally presumed.  So with my question, any experimental formula has has ALREADY BEEN CALCULATED TO DETERMINE THE REQUIRED HLB.  I seriously thought everyone would know that you should always calculate the required HLB of your formula, so that you can determine what type of emulsifier blends to use.

Thank you so much!  I appreciate that feedback because it has taught me what I need to do before posting any discussion piece.

[doctorbrenda]

Both Cetyl Alcohol and Cetearyl Alcohol (a mix of stearyl and cetyl alcohol) are solid “fatty alcohol” waxes.  These can be made from their respective fatty acid counterparts - Cetyl Alcohol (C16) from palmitic fatty acid, and Stearyl Alcohol (C18) from stearic fatty acid.  They technically, scientifically, have ZERO HLB value because they cannot emulsify anything.  In fact they each have an HLB requirement of around 15, which means by definition they cannot emulsify if they require an emulsifier to emulsify them.  Even a Low HLB emulsifier has some ability to draw water into oil (hence why they are used in water-in-oil emulsifiers, and need to be combined with a high HLB emulsifier in order to produce an oil-in-water emulsion).  That being said, they are often used as an emulsion “STABILIZER” because the long carbon chain length of fatty alcohols can help hold everything together better at the interface, particularly with a more unstable emulsion.  Because they have the quality, they are often indicated as “co-emulsifiers” which can cause confusion for many people new to all of this.