Black waxy residue from lotion

Formulating

Black waxy residue from lotion

Posted by Doaneventry on March 1, 2017 at 2:27 am

I made a cream. After really rubbing in the cream. A black waxy ball residue coalesces. I can’t figure out which ingredient is doing this.

Ingredient list:

Water, IPM, Glycerin, Carpylic/carpric Triglyceride, Cetyl Alcohol, Stearic Acid triple beads, (Sodium polyacrylate, hydrogenated polydecene, trideceth-6 Mixture), (glyceryl monostearate, PEG-100 Stearate flakes), Sunflower Seed oil.

I am very new to formulating. Any guidance would help. Thank you

belassi replied 8 years ago 4 Members · 12 Replies
12 Replies

belassi

Member
March 1, 2017 at 3:06 am

To begin, please list the formula properly with percentages.
EG
Water 67%
Isopropyl Myristate 5%
etc
Chemist77

Member
March 1, 2017 at 3:32 am

Is that that the complete list as I don’t see a preservative there. That mixture you are using at times shows incompatibility in presence of electrolytes, cationics and anything which might harm the polymer.
johnb

Member
March 1, 2017 at 7:50 am

It is most likely the emulsion breaking and coagulating on the skin. The blackness is dirt collected during the emulsion breaking.
Doaneventry

Member
March 1, 2017 at 5:34 pm

Water, 70.0%
Glycerin, 8.0 %
Caprylic/Capric Triglyceride, 5.0%
IPM, 2.0%
Cetyl Alcohol, 3.0%
Stearic Acid triple beads, 2.0 %
(Sodium polyacrylate60%, hydrogenated polydecene35%, trideceth-6 5% mixture), 2.40%
Disodium EDTA, 0.10%
Glyceryl monostearate, 0.5%
PEG-100 Stearate, 0.5%
SunFlower seed oil, 4.0%
Benzyl Alcohol, Dehydroacetic Acid mixture, 0.4%
Fragrance, 1.0%

ph ~ 6.5
Chemist77

Member
March 1, 2017 at 5:42 pm

Try knocking out EDTA and if I were you I would check my preservative too. Nothing else seems out of place there if I am not mistaken.
Doaneventry

Member
March 1, 2017 at 5:49 pm

I made a run without EDTA, and then Added EDTA because I thought I had an electrolyte problem. I do not believe EDTA is the problem.
Doaneventry

Member
March 1, 2017 at 5:51 pm

Do I need higher levels of my emulsifiers?
belassi

Member
March 1, 2017 at 6:27 pm

Do I need higher levels of my emulsifiers?
Yes, absolutely.
Doaneventry

Member
March 2, 2017 at 8:38 pm

@Belassi @johnb @Chemist77
I tried increasing the emulsifier levels to 3% and then 6%. and the black residue still comes out after rubbing in the cream.
belassi

Member
March 2, 2017 at 9:06 pm

You’ve got about 16% lipids in there. I would be using around 6% glyceryl stearate and 4% PEG-7 GC, but I’d have to do the HLB calcs first.
Doaneventry

Member
March 2, 2017 at 9:53 pm

@Belassi
HLB value of oil phase is 9.53. I am really unable to do much with my emulsifiers. It’s actually a blend of 50% glyceryl stearate and 50% peg-100 stearate flakes, whose hlb together is 11.

I tried to adjust the ingredients amount to be close to 11 as possible while trying to make the lotion look and a certain way per client request.

Does it matter that much if the hlb value of emulsifiers is off by 1 or 2?
belassi

Member
March 2, 2017 at 11:57 pm

Does it matter that much if the hlb value of emulsifiers is off by 1 or 2?
No. Just keep increasing the emulsifier until the system works. Also you MUST use high shear.