Saturday, April 30, 2011

Duplicating products: Philosophy's Hope in a Jar

I've already broken down the ingredients for the Hope in a Jar in this post, but I'll repeat it here with an eye to duplicating it. As a note, this is the Hope in a Jar product, not one of the variations (click here for the Sephora link). And as a note, I don't see any difference in the ingredient lists for the dry skin version, but there could be differences in the amount of the ingredient used.

Water - the solvent.

Glycerin - our humectant.

Rice Bran oil - our oil. Shelf life about 12 months.

C12-15 alkyl benzoate - an ester that feels light and offers good slip and glide, as well as fragrance fixing properties. Shelf life about 24 months.

Glyceryl stearate - part of the emulsification system. A low HLB emulsifier (5.8) that is used with a high HLB emulsifier to create an emulsification system.

PEG-100 stearate - a PEG ester that comes in a waxy format. It acts as a thickener, opacifier, and emulsifier. It's probably part of the emulsification system along with glyceryl stearate as the high HLB emulsifier (18.8).

Octyldodecanol - A fatty alcohol, but one that comes in a liquid form. It offers thickening and emolliency to our products as well as stabilization of emulsions and a reduction of foam when a product is shaken.

As an aside, this is a Guerbet alcohol, which is a branched chain fatty alcohol that will have a much lower melting point than a regular fatty alcohol like cetyl alcohol. This means it is liquid at room temperature. If you want to learn more about the differences between regular fatty alcohols and Guerbet alcohols, click here. If you want to learn a lot more, click here. And if you want to learn even more and learn more about how they are made and learn about Guerbet acids, click here.

Cetyl Alcohol - A fatty alcohol that offers slip and glide, as well as thickening to our products. Also acts as an emollient. It has a required HLB of 15.5.

Stearyl Alcohol - A fatty alcohol that will offer thickening to our products and it acts as an emollient. It has a required HLB of 15.5.

Lecithin - An emollient and emulsifier. It could work as an emulsifier in this product with an HLB of 4 of 9.7.

Tocopheryl Acetate - Vitamin E. Behaves as an antioxidant. It has a required HLB of 6. Generally used at 1% or less (and probably far less for a commerical product).

Retinyl Palmitate - Vitamin A. Good for your skin. It has a required HLB of 6.

Arachidyl Propionate - A semi-solid wax that melts on contact with our skin. It's non-greasy feeling. Required HLB is 7.

Ethyl Linoleate - an ester of linoleic acid. It can be used as an emollient or fragrance ingredient. It has an HLB higher than 10.

Ethyl Linolenate - an ester of linolenic acid. It can be used as a fragrance or flavour ingredient. It has an HLB higher than 10.

Citric Acid - pH adjuster. Used at 0.2% to reduce the pH about 0.9.

Lavandula Angustifolia (Lavender) Oil, Salvia Officinialis (Sage) Oil, Limonene & Linalool - fragrance ingredients

Diazolidinyl Urea, Phenoxyethanol, Methylparaben, Propylparaben - preservatives

So here's the problem with this product. Where can we find octyldodecanol, arachidyl proprionate, ethyl lineolate, and ethyl linolenate? I have no idea. The last three are probably in small amounts as they come after the Vitamin E and A, so we could substitute them for other esters, but the octyldodecanol is just behind the emulsifiers, so we know we'll need it at least 1%, and it seems pretty important for the skin feel and the emulsification of the product.

The other problem is that we don't know if the ethyl linoleate and linolenates are in there as fragrance products or skin feel products. Do they have a role in how the product feels or smells? If it's about the smell, then we can add other things to make it fragrance. If it's about the skin feel, even a small change can make a difference in our products. I'm going with the notion that these esters are for fragrance, so I won't worry too much about leaving them out, but I could be wrong, and the skin feel might be different.

We could substitute some other esters for these ingredients (except the octyldodecanol), but it won't have the same skin feel as the original. I know they probably don't make up a lot of the product - they're in the 1% or less category - but a little change can make a big difference. As for the octyldodecanol, I think this is a really important ingredient, but I can't find it anywhere, so we'll have to leave it out and hope we can get the skin feel in other ways.

And one final problem - I'm also not that sure where to get stearyl alcohol on its own. We can get cetearyl alcohol, which is a mix of cetyl alcohol and stearyl alcohol (sometimes it's 50-50, sometimes it's 30-70), so we could use that in our product (which would make sense because we see the cetyl alcohol above the stearyl alcohol).

And a final note. Lecithin can be used as an HLB emulsifier with an HLB of 4 or 9.7. Since I have no idea which lecithin I own, I'm going with the idea that this is another oil. I'll add it to the oil phase at 1% without an HLB amount (so I won't count it in the calculations of how much emulsifier I'll need). If you know the HLB value of your lecithin, you can use it as you calculate your emulsifier with the glyceryl stearate (HLB 5.8) and the PEG-100 stearate (18.8).

I think the key to this product is making it thickish without making it greasy. I'm thinking about cetyl esters as a replacement for octyldodecanol. I know it's not a great replacement, but it will offer thickening and emolliency. I'll try those at 3% and I'll try the cetearyl alcohol at 2%. (The HLB will be the same for cetearyl alcohol as it is for cetyl alcohol and stearyl alcohol - 15.5.)

I think there's maybe 3% rice bran oil, 3% C12-15 alkyl benzoate in here (I'm going by the fact that the glycerin appears higher than these two oils), but I'm going with 5% of each because it's easier for me to make something thicker for a first try and then reduce the oils. Because we don't have the octyldecanol, we need some emollients in here beyond the fatty alcohols.

So which ingredients are oil soluble and have HLB values? It makes up 16% of the recipe.
5% rice bran oil - HLB 7 -
5% C12-15 alkyl benzoate - HLB 13
3% cetyl esters - HLB 10
2% cetearyl alcohol - HLB 15.5
0.5% Vitamin E - HLB 6
0.5% lavender essential oil - HLB 12

Our required HLB for this product is 10.625. Wow, that's high! So if we're using glyceryl stearate (HLB 5.8) and PEG-100 stearate (18.8), we'll need to use 2.52% glyceryl stearate and 1.48% PEG-100 stearate (and it's okay to round those to 2.5% and 1.5% respectively in this case).

Yes, essential and fragrance oils have HLB values and we can figure those out for our products. Most fragrance oils are around HLB 7 and a lot of our essential oils are in the 12 to 13 HLB range. You don't really need to include them in the calculations because you're not using a lot and if you're using 4% to 5% emulsifier, you have enough to compensate for them. I'm including the lavender essential oil in this calculation to round it up to 16% instead of working with 15.5% as my oil phase. Plus, it's good to know these things! 

If you want to use an emulsifier like Polawax, BTMS-50, or e-wax, with a 16% oil phase you'd use about 4% emulsifier. If you're using another emulsifier - like Ecomulse/Natramulse - you'll have to use it at its suggested rate and remove some of the water to compensate (it's a coincidence that it's 4% for each).

For the water phase, we have two ingredients - water and glycerin. I'm thinking about the glycerin at 3% and the water will make up the rest of the product.

Let's take a look at a possible duplicate recipe...

POSSIBLY A DUPLICATE FOR PHILOSOPHY'S HOPE IN A JAR
HEATED WATER PHASE
75.5% water
3% glycerin

HEATED OIL PHASE

5% rice bran oil
5% C12-15 alkyl benzoate
3% cetyl esters
2% cetearyl alcohol
1% lecithin
4% emulsifier (2.5% glyceryl stearate and 1.5% PEG-100 stearate or a complete emulsifier like Polawax, e-wax, or Incroquat BTMS-50).

COOL DOWN PHASE
0.5% Vitamin E - HLB 6
0.5% lavender essential oil - HLB 12
0.5% preservative

Follow the basic lotion making instructions for this recipe.

As you can see, duplicating products isn't as easy as it seems! Commercial products will often use a little bit of something you can't get, and as we know, a small change can have a huge impact. Play with this recipe to get the skin feel you want. Try different esters, more fatty alcohols or fewer, and get to a point where it feels more like the real product!

Join me tomorrow for more fun duplicating products with Philosophy's "cult" cleanser Purity Made Simple (another suggestion from Aesthete!)

3 comments:

p said...

Could you talk a bit more about Ethyl Linolenate and Ethyl Linoleate as fragrance ingredients? Do they have scents on their own? What do they smell like? Or are they fragrance fixatives?

Heela said...

Octydodecanol available at makingcosmetics.com I use it to dissolve salicylic acid (works pretty well). Its a solvent, as well.

Fortitude Provisions said...

Hi there!

I was reading about HLB values of essential oils, and encountered your very useful blog! Quick question – I make room sprays with essential oils (about 4%) and a combination of Poly20 and Poly 80 at a 2:1 ratio to essential oils (8%).

Most of my sprays are transparent when I make them, but slowly turn cloudy. It's a serious issue with Lavender EO, which turns almost creamy white. Should I be using another emulsifier instead? I've heard some people recommend Hydrogenated Castor Oil, but haven't gotten around to testing it. Any ideas?