Tuesday, September 29, 2009

HLB - a short summary and a few links

I figured now that you've seen the HLB system in action, it's time for a summary.

The HLB system is designed to make it easier to figure out what emulsifier goes with what lotion. Your oil phase will have a required HLB value, meaning this is the number you need to match with an emulsification system composed of a high HLB and a low HLB emulsifier.

If you have an oil phase with a required HLB of 8.1, you'd choose two emulsifiers in ratios that will total 8.1. (Cetereath-20 with an HLB of 15.2 and Glycol distearate with an HLB of 1 at 50% each will match this number). If you're using 4% emulsifier, you'd use 2% ceteareth-20 and 2% glycol distearate in the recipe.

If you have an oil phase with a required HLB of 6.225 and wanted to use polysorbate 15 (HLB: 15) and glyceryl stearate (HLB: 3.8), you'd end up using 22% polysorbate 80 (or 0.88 grams) and 78% glyceryl stearate (or 3.12 grams) if you're using 4% emulsifier.

The key to the HLB system is finding the right ratio of emulsifiers to the required HLB value of your lotion. You can use any combination of high HLB and low HLB emulsifiers you like, as long as they are in the right percentages in the recipe. It's up to you to figure out which combinations you like!

Want to know more about HLB? Here are a few links I like...

Emulsifiers with HLB values from the Herbarie.

Required HLB values for oils from the Herbarie.

Making emulsions for cosmetics from Makingcosmetics.com

Have fun!


Anonymous said...

I have some questions. Does it has any different if I use the difference emulsifiers? For example, if I use Glycol Distearate HLB = 1 and Ceteareth-20 HLB = 15.2 , or I use Polysorbate 80 HLB = 15 and Lecithin HLB = 4. I know the amount that use to make lotion must be difference. I want to ask you that will they have any effect to lotion that I make in case of potentiality, quality, and etc.

Sorry if I make you confused, I am not good at English.

Your blog is very informational.
Thank you very much for sharing the informations

danserenpetiteculotte said...

Hi Susan!
I have a question about HLB for you, hope I'll be clear enough (English isn't my native language).
When you're talking about an HLB required, is it required for the emulsion to be possible? If it is, I'm not sure to understand how we're supposed to play with the texture (and especially with how thick the preparation will be). With fatty alcohols for example?
In that case, would it be accurate to assume that formulating a lotion starts with : choosing oils and fatty alcohols, then appropriate emulsifiers (for their spreading, thickness, protective, etc properties), and finally calculating with their HLB proper amounts?
I guess my question really is : how can I make sure my preparations are thick enough (I loooove thick creams or conditioners, but I usually put very small amounts of oils and butters into them, so obviously, thickness is a recurrent issue...)?
I'm litterally spending a decadent amount of time reading your blog for the last week, but haven't found those information yet...
Thanks in advance!

Susan Barclay-Nichols said...

Hi Danserenpetiteculotte. Are you asking if we should design a recipe with all the ingredients we want and then figure out the HLB of the recipe?

danserenpetiteculotte said...

Yes Susan, I guess that's what I was asking about. As I emailed you, I'm used to a very different approach of formulating and am not sure how you do control thickness in a formula using the process you're describing here. If I understood properly, I should check more the posts about fatty alcohols/acids and test them to find the ones I like (which would be quite new to me). Thank you for your help anyway, I'll get back to you with other (better) questions in the next few weeks or so :-)

tripl3thr33 said...

Hi Susan,

Love your blog very much. I studied Chemistry before and never really understood the importance of this HLB value until recently when I started formulating stuffs.
After reading some posts in your blog, I have a question for you.
I understand that if you don't agitate your mixture well enough, even with the correct HLB value, you won't get a nice homogenous milky emulsion and the water and oil phases might just separate.
Could you give me some tips on how long and how fast should I mix my water and oil phases? And how can you differentiate whether an emulsion separates because of inadequate mixing or because of incorrect HLB calculation?

Fyi, I am formulating silicone emulsion, which as you know, (silicones) have a wide range of required HLB values from 8-12 or more. Therefore, I am uncertain whether my mixing technique is incorrect or simply I haven't nailed the correct HLB value.