-
Emulsifier calculation for lotion brings ‘negative’ amount - help..!
Hello,
I use the basic calculation to work out the required HLB for lotion but the reult amount is ‘negative’ amount: ‘minus’.
I use 2 type of so called or classified under ‘natural’ emulsifiers, to create a cleansing face lotion and here’s my formulation breakdown:
OIL PHASE (Total 21 gram oil):
2 Cocoa Butter [HLB 6]
1 Beeswax [HLB 12]
10 Castor Oil[HLB14]
6 Sunflower OIl [HLB 7]
2 Cetearyl Alcol [HLB 15.5]
?? Sodium stearoyl lactylate [HLB 8.3]
WATER PHASE:
63 Water
3 Glycerin
?? Glycerol Mono Stearate SE HLB 3.8
THIRD STAGE:
1 Vitamin E [HLB 6] (**should I have included this into the TOTAL OIL PHASE?)
3 Coco Glucoside (HLB 13)
1 Preservative
___________
100 gram
REQUIRED HLB TOTAL = 11.29
Ideal total Emulsifier amount I am looking is 6 gram of 100gram-total formulation of above.
The calculation I used is based on below:
GMS required = (Required HLB Total - SSL) ÷ (GMS - SSL)
SSL required = 100% of Emulsifier less above GMS total
Which is:
GMS = (11.29 – 8.3) ÷ (3.8 – 8.3) = -0.6644..x 6 = -3.99
SSL = 1 - (-0.6644) x 6 = 166… = 9.99
So it works out
Glycerol Mono Stearate SE [HLB 3.8] -66% of 6% Emulsifier = -3.99 (minus 3.99)
Sodium stearoyl lactylate [HLB = 8.3] 166% of 6% of Emuslifier = 9.99
This time, HLB total required amount being 11.29 the same calculation brings to the negative amount.
I’m a bit stuck as to what to do…
Usually I use the same calculation with Oil phase around15%, Total emulsifier to 3-4% of formulation. it’s successful using the same method of calculation using the same 2 Emulsifiers.
Most of those formulation’s HLB ended with required amount around 7.2 – 7.9, and but this time the Total required HLB ended with very high at 11.29.
Where did I do wrong? Or What would be the solution?
Any advice would be appreciated.
-
4 Replies
-
1. that HLB value you’ve quoted for GMS is for the non self-emulsifying grade; the S/E grade contains sodium stearate (anionic), and because it’s ionic it has no HLB value
2. by the same reasoning, any HLB value quoted for sodium stearoyl lactylate is meaningless because it too is anionic
3. switch the phases of GMS and SSL, i.e. put SSL in your water phase and GMS in your oil phase; as it stands neither of them will mix properly
4. try experimenting with a few different levels of GMS and SSL, starting with a 1:1 ratio, and see what works best
good luck!
-
Vitamin E belongs in the oil phase.
-
The HLB system cannot be used for lactylate emulsifiers.
There is a system called LINDEX developed by RITA Corporation for lactylate emulsifiers.
-
Data for the LINDEX system is not available online anywhere. You need to contact RITA directly to get it.
Log in to reply.