[Zoya]

It looks fine to me. Yes, polymerics can be on the pricier side and yes, decreasing them in the emulsion may reduce the stability of the emulsion, but you have to test it, it’s difficult to answer without testing it properly. Sepimax zen has a fresh sensation on the skin, while sepinov emt is ‘more greasy’ in high concentration, in my experience. Reducing them also affects product viscosity, so you should also take this under consideration. Have you also tested it for SPF?

[Zoya]

Hi,

If I understand well, nothing else changed in your base formulation which doesn’t stick, neither raw materials nor suplliers or percentages, so you are sure, what you feel is caused by HA.

In that case: Sodium hyaluronate mol.weight < 10 kDa is less sticky, than higher mol.weights (10-50 kDa, 800-1500 kDa,…). If the CoA doesn’t tell what molecular weight yours is, you better ask the supplier. The smaller mol.weight HA usually pricier. You can change the mol. weight of HA or adjust the percentages of other components in the base for better skinfeel.

[Zoya]

Hi Lab,

You may find this useful:

https://www.ulprospector.com/knowledge/6458/pc-settle-down-factors-that-influence-pigment-settling-and-stability/

Good luck! 🙂

ulprospector.com

Settle Down: Factors that Influence Pigment Settling and Stability

Introduction -The first steps in the pigment dispersion process are wetting and separation of the pigment. However, if the pigment dispersion is not properly st

[Zoya]

You can always try to play around with percentages but without changing raw materials your formula probably won’t function well. As ketchito said, you don’t have enough lubrication without adding esters (or oils). I would switch up at least a part of cetyl alcohol to a waxy ester like cetyl palmitate and also add a little ester in liquid form to reduce rigidity even more (and have Conditioning effect). Cetyl alcohol in 5% gives too much rigidity to your formula and can also lead to stability issues.

[Zoya]

Did you try rising the temperature to around 90 C, than adding the ceramide and keeping the temperature there until fully dissolved? Method can be crucial in this case, I would give it a try.

[Zoya]

What does your oil phase contain?

You may use an additional high HLB emulsifier (I never trust only one) and you can also use a gum or polymer to help in stabilization.

[Zoya]

Thank you gordof! I was thinking of something similar. 🙂

[Zoya]

Oh and also leave out vitamin E, even with high oil concentrations you probably won’t need that much - especially in a shampoo.

[Zoya]

I don’t think fancy moisturizing ingredients are needed in a shampoo because all of them will be rinsed off. You better go with polyquat or cationic guar which ‘stick to the hair’ and have that Conditioning effect - save some money by leaving out well-branded moisturizing actives. BTMs will destabilise the product - and you also have cationic guar so it’s useless in here. If you want some pearlizing effect add a hint of Glycol distearate. You may consider adding some anionic surfactant to make it more gentle to the hair and scalp and have some nice bubbles. Leave out the oils or keep 0.1-0.5 % for marketing.

[Zoya]

Didn’t you experience something uncommon during stability testing?

Have you made a sample without perfume? It can also cause cloudiness if some incompatibilities happen between perfume components and surfactant systems.

[Zoya]

Hello,

I’m here to do an update (it may be helpful for others): reducing the scg seems to solve the problem. I’m still not finished yet but I finally see where I’m going.

[Zoya]

Hi,

At specialchem I find some info ‘faster’ than at Prospector (ie. percentage of active - I don’t have to download a PDF)- but Prospector may have more info about the raw material. I use both of them, depends on the circumstances.

[Zoya]

Hi,

As a consumer I would choose concealer for full coverage and foundation for a more pleasant wear during the day with medium coverage so it does make sense to me that concealer has higher percentage of TiO2.

[Zoya]

I wonder if it could be from free charges available in the surfactant solution - has anyone experienced something like this? First, I tried to slightly increase the amount of nonionic surfactant to see if it makes any difference - for now it seems a little better but I still need more time to test it properly.

Sometimes I feel this ‘itchiness’, especially when working with amphoteric or anionic materials, that’s why I’m suspecting the charges in this case too. A balanced surfactant solution wouldn’t cause this feelig - am I right? I’m still quite a beginner in blending sole surfactants together so any advice would be appreciated, thank you very much. @Perry44 @MarkBroussard @Paprik @chemicalmatt @ketchito @Bill_Toge @fareloz if you have some time please help me solve this mystery 🙂

[Zoya]

Hi Paprik.

Thank you so much for your reply. I was thinking to use it as the anionic surfactant for a slightly acidic cleanser, as I have successfully made stable and functioning liquid gel cleansers with it - but in those cases the pH was 6. I have never tried to bring pH down as I was worried of hydrolisation and I planned to use a glutamate for the lower pH cleanser because they tend to ‘work’ between pH 4-6. Unfortunately I don’t have much luck with glutamates lately so I considered changing the anionic surfactant to SCI. Seems a bad idea now. Still don’t know what to do, I have very few options to use as surfactants.

[Zoya]

Ah and for a hair product you better use less oil to make it less greasy and appropriate for a leave-in hair product, so cut the oils down to 05-2* the amount of the emulsifier and use more viscosity builder and waxy emulsifiers for the desired viscosity. Also, you can use liquid polyquat up to 5% (the active is usually under 10% of the solution).

[Zoya]

Hi,

You can find starter formulas on the internet. As a guide, you can use this:

Emulsifier: 2-6% (depends on the type of the emulsifier, end consistency, quantity of the oil phase, etc) and 0.5-1.5% co-emulsifier

Viscosity builders (fatty Alcohols, etc): 0-4% as needed (depends on the desired end viscosity)

Shea butter: 1-3%

Oils: approx. 4* the quantity of the emulsifier(s)

Glicerin:2-10

Gums/polyquat: 0.05-0.3%

Tocopherol: 0.05-0.5% (depends on the formulation)

Preservative (!): as proposed (depends on the preservative and on other circumstances, i.e on which skin area you use the product, packaging, etc.)

You can start with an avarage of the usage rates I mentioned above and build the product up from there. Always change one thing at a time and make your observations after every change, that way you can learn how those little changes affect the whole product.

[Zoya]

Hi,

I have never used ceramides before so apologies for guessing, but as I can recall, working with ceramides oil phase needs to be heated to 90C. Also, the majority of oils have to be good solvents for ceramides, like C12-C15 Alkyl Benzoate or Caprylic/capric triglyceride.

[Zoya]

Hi,

You need a stronger preservative system for your formula and also a solubilizer. The ‘smell’ may come from Carrageenan gum, you can make a knock-out test and leave out Carrageenan.

[Zoya]

Hi,

I just found this old post and I would like to know what homogenizer could you propose for dispersing pigments and ZnO in a w/o emulsion?

For Zno, I’m currently using a pre-dispersed version (Zno in Caprylic/capric triglyceride) and I also use pigments to cover the whitening effect of ZnO. For ‘home-experimenting’, I’m using a simple homogenizer. The emulsion seems stable (but still under examination) and homogenous, however after applying it several days in a row, I experience comedogenicity. I’m wondering, could it be because the pigments (or Zno) haven’t been fully dispersed in the formula (or is it natural with this high level of Zno - around 20%)?

Thanks.

[Zoya]

Thank you Chemicalmatt. 🙂

[Zoya]

Thank you, fareloz 🙂

[Zoya]

You may try adding some more polar oils/emollients like castor oil, avocado oil, cocoglycerides, triisostearin, etc.

[Zoya]

Hi ketchito,

Thanks for the idea, I order some and play with it. I’m also experimenting with glutamates right now, they can tolerate lower pHs as well.

[Zoya]

Hi KatieW.

You can try cationic guar gum instead of Carrageenan, it’s quite beneficial for the hair (make sure you order the cationic one). For preservation I would completely change or at least add Benzyl Alcohol or Pehentyl Alcohol for the above system (they both smell nice, so double-win) - but here we have more experienced chemists than me, I’m sure they can help you with the preservation. For solubilizer, you have many options, if you would like to stick with the ‘more natural’ ingredients, you should try Oramix CG 110 (3:1 solubilizer : oil but different oils need different ratio so you have to play with it) or Polysugamulse D9. Otherwise, PEG-s can easily do the job.