[Eli]

Thank you for this info. I might use polyquaternium 37 as a first candidate and as you mentioned Perry a lot of petrolatum. When I mentioned carbomer I was imaging that they will trap the moisturizing ingredient and release it slowly in the skin. But I guess once the cream is spread the micro gels of carbomer will completely break at once. Thank you again !

Perry in that test, how did you measure the moisturizing effect on the skin. ? Which method. Thanks.

[Eli]

Thank you very much guys! Also for the examples. I was evaluating Stabylen 30, a polymeric emulsifier similar to a carbomer with hydrophobic characteristics. I guess it is not so well known as the ones you are mentioning. First it is better to search for formulation restrictions as you suggested 

@MakingSkincare

[Eli]

Thank you for the answer! So any liquid emulsifier can be use for cold process?

[Eli]

you’re right! i’ll try ! i need to search in which proportion i have to use it to get negative the test : EN 1276 Chemical Disinfectants Bactericidal Activity Testing.. otherwise i can’t sell the formula. Thanks again

[Eli]

Thanks @milliachemist, but for example which product of 2 phase liquid do you have in mind?

[Eli]

Thanks @milliachemist ! I have data that shows it has better killer properties than triclosan but about the formula compatibly I don’t know which one is more flexible yet…

[Eli]

What do you think about Triclocarban?

[Eli]

@tonyh thanks for your comments about stabilizing Piroctone Olamine. Can I ask you in this formula I am using which ingredient is used to stabilize the Piroctone ? Ingredients : Aqua , SLES, propylene glycol, sodium dilaureth 7 citrate, sodium chloride, decyl glucoside , propolis cera, Piroctone Olamine , PEG 55 propylene glycol oleate, citric acid, Parfum, alpha isomethyl ionone, phenoxyethanol, methylparaben, ethylparaben, propyl..butyl…

Also I was wondering if propolis cera is a good agent as an anti dandruff ? I think here they used it exactly for that meaning. Thanks !

[Eli]

Thank you very much for the answer Bobzchemist, pointing out the exact difference btw food and cosmetics made me realize it is a serious thing when we talk about safety in cosmetics.. you are right ! The eye doesn’t have defense systems like the digestive track.. great example!

About lawsuits it is still a mystery how a consumer can prove the bacteria comes from the use of that specific cosmetic? If consumer is always right, then big companies must be scare about them. .. 

[Eli]

i correct - they are not often called carbomers, but we usually put them in the list of carbomers, like acqua-SF1 for example.. 

[Eli]

There are many types of Carbomers and they change basically in:

1. Their resistance to salt which is often correlated to the suspending power (for ex, if you want to suspend some beads inside the shampoo you should use Acqua SF-1). Also if the polymer is not resistant to salts at all even if you don’t add salt in the final formulation, when you put a drop in your hand it will slip very fast because the electrolytes of the skin will cause this sudden drop of viscosity. Otherwise it will stay longer. 

2.The range of pH where they work the best. Some pH gives you a great transmittance but lower viscosity and others a good suspending but not so good clarity, so depending on the final pH of the formula you can choose the best carbomer to satisfy those characteristics). Raw materials suppliers always say the range of pH where they work ok, and not all of carbomers have the same. 

3. The rheology changes a lot if you compare with some other products that are still acrylic acid polymers but hydrophobically modified (-some of them made to satisfy some food claims as budding, butter, jelly-) they are often called carbomers due to its similarities but they develop higher viscosities and rheological behaviors due to their associative power of their extra hydrophobic chains.

[Eli]

Hello everybody! I was wondering some things about microbiology because i went to a cosmetic event yesterday where one of the speakers said: Maybe in the future cosmetics will be treated as food, and they will be store in the fridge ! and that phrase keeps moving in my mind .. Is it really possible? maybe it is actually a good idea but too expensive to create the chain of cold.. from supermarkets and distributors etc.. 

My question is, does every cosmetic form need a preservative system ? like powders (dry shampoo), or oils (i guess oils can also develop microbes). Would it be useful to use the fridge once we open a cosmetic product and start to use it ?

Thanks!

[Eli]

Hello again! I was starting with sun care some months ago and after reading a lot of opinions about Avobenzone + EHMC (octinoxate) i can’t seem to understand why if there is such a unstable mix people keep using it everywhere. I know they are not used alone but with octocrylene stabilizing avobenzone, and sometimes even small amounts of EHMC are used.. like 0.5% does it actually makes sense? Maybe i have still a lot to learn, but every time i read more about the subject i get more confused. !!.. and anyways the products i check in supermarkets and everywhere they use that wonderful threesome of UV filters: BMBM, EHMC and OCR.. Thanks !

[Eli]

Hello Ben,

Thank you so much for your answer. That solved a big problem I had. Relative to the type of microbe or details of production sadly I do not have access to that information but it is nice to know that there might be some type of microbe that can “come back to life” somehow… Thanks again. !

[Eli]

Hello Ben, I have maybe two very stupid questions but … Do saturation of germs can cause lost of transmittance in a water based solution?

And another one … If I dry a slurry full of germs (or leave a small amount of water) and leave it like that for several months… Adding water do they “wake up” again?

[Eli]

Yes it helps a lot, thanks @cosmochem and @pma ! What do you think about micro encapsulated avobenzone? Would it really be more stable ?

[Eli]

Can I neutralize amphomer with NaOH ? Because I am using another polymer in the formula to thicken that works pretty good with NaOH.

[Eli]

Thanks a lot @milliachemist. I am waiting for the supplier answer but I will start the trials. !

[Eli]

Thanks @milliachemist. The surfactant is polypxyethylene C12-C15 ether. I found it’s cloud point at 1% around 48 and 52 C. But I don’t know how much it changes when it is in pdiol instead of water.

[Eli]

Thanks @milliachemist! This process doesn’t happen in the final formula but in the dispersion phase with a premix base. We don’t want to store the slurry (microbial problems) of the optical brightener but the final powder solved in a premix soap base with the optical+surfactant+ Pdiol. To this premix solution it will be added the rest of the raw materials. Correct me if I am wrong but if the optical particles are supposed to stay inside the micelles how can I pre-dissolve it without the surfactant? l heated the surfactant separately but it doesn’t seem to show any change at all.. The only worsening effect of the transmittance is when it is in solution with the optical. Another hypothesis was that the optical in powder would have calcium or magnesium that will affect the solubility in the premix base, because cleaning it before with EDTA sometimes it works. Only sometimes… I can’t figure out what else could be worsening the solubility and transmittance.

[Eli]

Hello everyone !! Nice to read all your life stories. All of you have very interesting profiles and i am looking forward to share some time and learn new things with you! This is enormously motivating ! 

I am a chemical engineer graduated in Venezuela. I did my thesis about the stability of multiple emulsions and that is where my love and interest for cosmetics started (even though this emulsions where not use directly for cosmetics but for water treatments). After that i worked for 4 years in R&D in Spain studying the properties of natural and synthetic Ceramides (not related to cosmetics again ! - somehow i am still trying to find my way). 

And finally now i am going to start working for a very nice italian company of raw materials in the cosmetics division. I am looking forward to learn a lot about all the ingredients used in the industry, mainly because i might end up working in the technical marketing or in the export department (don’t know yet). All the information is well received !

I decided to joined the Practical Cosmetic Formulating course because it seems a very complete course where i will learn a lot about the industry. I am really excited to start, i am so happy that i found Chemistcorner, it seems to be a pearl of knowledge. Thank you Perry and all the experts in the field !