[Pharma]

Shouldn’t the first question be: What do you expect from silicone ingredients in your product? Silicone doesn’t equal silicone.

Cyclodimethicones are volatile and if you’re after that feat, undecane/tridecane or related hydrocarbons are certainly worth checking out. However, they feel terrible when tested neat, like spilling a solvent (which they basically are) over your hands at the lab :smiley: .

[Pharma]

I don’t know how good an antimicrobial farnesol actually is. Literature suggests that it’s mostly a quorum sensing molecule which stops yeast from switching into the hyphen form and bacteria from building biofilms. Both are not (should not be) an issue with cosmetics and play no role in malodour.

[Pharma]

With our chemistry (the one of our reality and on our planet), it is virtually impossible to create ‘green’ molecules with all the virtues of silicones. Some like volatility can be achieved, but the immiscibility with water and oils (which is one of the reasons silicones feel the way they do) not so much. Maybe poly- and perfluoroalkyl derivatives would work though I don’t know how they compare feel-wise. However, those are way more synthetic than silicones and are very persistent in nature (= they are higher up on the ‘ugly’ list). Better stay with silicones than using halogenated stuff (or let your dream fade away like any beautiful dream fades when you wake up in the morning).

[Pharma]

In vitro data suggest that 0.062% farnesol is more than enough (especially if combined with other antimicrobial ingredients). True, preservatives and deodorising ingredients are usually used at many times higher concentrations than what’s needed in vitro but 0.062% is already >3 times higher than the highest one I could find in a quick&dirty google search.

[Pharma]

Be aware that a cosmetic product in the EU has to be safe and can not have a pharmacological effect beyond the skin. Methyl- and ethylsalicylate are small lipophilic and highly skin permeable compounds. There is no safe and really legal way you could sell a product with a concentratio well above that of a perfume ingredient.

Also, the ‘designer drug approach’ only works in some cases and in some countries but it does not work for legal drugs (it only works for legal chemicals and non-restricted cosmetics vs. prohibited chemicals or regulated drugs). See regulation for methylsalicylate HERE. Ethyl salicylate is not (yet) in the annex VI but it is a potentially irritating ingredient and ‘creating’ a safety document for pharmaceutically active 10%… ugh… try 100x less . If you want 10% then you want a pharmaceutical activity -> either register as such a product (which I would recommend if you’re willing to explore that rabbit hole), look for another project (you can’t replace someting with a desired pharmaceutical effect without using another activce pharmaceutical ingredient), or… (that’s the point where I stop, I’m not going to mention illegal doings as an alternative).

[Pharma]

Will your butter be an emulsion (o/w or w/o) or be anhydrous?

To make o/w emulsions feel like a butter, you have to use lamellar structure builders, in the range of 10-20% I guess, when using sucrose monoesters as main emulsifier. GMS, fatty alcohols, and/or esters such as cetyl palmitate would be my starting point. Also, waxes and hydrogenated oils can be helpful.

For w/o GMS or any other low HLB (high HLD) co-emulsifier such as Span’s (sorbitan esters) or low N° polyglyceryl (poly-)esters.

In anhydrous formulations, I can’t see any real benefit in sucrose monoesters.

Download (and read) Sisterna Formulation Guide 2020. However, their sample body butter requires sucrose distearate, too.

Honestly, I wouldn’t use sucrose monoesters for that project!

[Pharma]

chemicalmatt said:

…The polyglyceryl esters (i.e. polyglcyeryl-6 laurate) … need co-emulsifiers to succeed.

Any you can recommend due to own experience or which you just prefer over others?

[Pharma]

@Microformulation Just lemme send you a thumb drive; plug it into your left ear, unzip, mount the image, run the exe. file with full admin rights, and install to your left temporal lobe and you’ll know everything there is to know.

[Pharma]

drsimranjit_lv said:

…Also suggest a good source to understand emulsifiers in detail if anyone is aware.

Maybe THIS or a book?

[Pharma]

That pH range offers room for a fair amount of suitable buffers.

I’m not a fan of carbonate buffers due to a possible formation of carbon dioxide.

As @Perry said: No complete formula = no useful advice.

[Pharma]

@ketchito I stay correted. I completely ignored BHT and related radical scavengers but was mentally locked in ‘traditional’ antioxidants. Because BHT is a sterically hindered ‘monophenol’, it is quite oxidation stable though I assumed even those phenolics couldn’t take such an oxidative environmentand. But yes, capturing radicals should indirectly render peroxides more stable. I just couldn’t come up with anything stable enough…

[Pharma]

I would use phytate because it’s the one which comes to my mind with the best oxidative stability. Maybe there are other untypical products which might increase BP stability?

@ketchito‘s advice to use an antioxidant in an oxidant formulation… maybe not the best idea…

[Pharma]

How many % urea do you have with regard to water?

[Pharma]

Chelates can help (depending on purity of your ingredients).

[Pharma]

One pink/orange/red colouring bacterium is Serratia marcescens, it’s ubiquitous and an opportunistic pathogen.

Another colour can be produced by Pseudomonas aeruginose (also an ubiquitous and opportunistic pathogen). Its pigments are greenish blue, yellowish and dirty red. Colour pigments change to red at lower pH which might result in pink hues in a product.

[Pharma]

Such polymers need at least some water and a suitable base for neutralisation. Pure glycerin would require something different (don’t ask me what exactly).

[Pharma]

I’m also for polyglyceryl esters.

I haven’t tried the ones mentioned above but PG-10 laurate: I like it though I think it’s best used in blends if intended as emulsifier (for example with sucrose esters as aqueous stock solutions for cold process) and results in low viscosity emulsions and a light (wet to powdery) afterfeel.

Other liquid ones are PolyAquol LW and VO4 or polyglyceryl-6 caprate and caprylate (never tried these). The latter two are often used as solubilisers rather than ‘classical’ emulsifiers. If you want to adjust for HLB/HLD values, combine with lower N° polyglyceryl oleates or isostearates which are all liquid.

Fitting to your PEG-100 stearate, liquid Tween’s may also be an option.

[Pharma]

Lemons don’t contain that much ascorbic acid but lots of citric acid .

[Pharma]

@Chemist77 Sounds plausible. Didn’t think of that one.

[Pharma]

A cationic emulsifier/surfactant sticks to the skin like one pole of a magnet to another one with the opposite pole, thereby stretching its lipophilic tail into the air. Cationics form a one molecule thin layer on top of the skin. This so called ionic bond is a fairly strong bond, the strongest non-covalent one (covalent means that the two partners form a single new molecule). Washing off is hence possible with enough salts/electrolytes (these act like a bunch of small magnets which distrub/disrupt the emulsifier-skin bond), by friction, and by desquamation.

An anionic sugar can, hypothetically, stick to positive charges on the skin the same way (just that the ‘magnetic poles’ are the other way round). However, sugars are hydrophilic, the resulting skin feel will be different. Due to a lot less ‘free’ positive charges on skin and the smaller molecular size of ‘sugar acids’ (= uronic acids, a type of polyhydroxy acids), these may penetrate somewhat deeper into skin than cationics (and hence don’t ‘feel’ but do whatever marketing tells them to do :smiley: ).

The hypothesis by Pentavitin is that neutral sugars which penetrate even deeper (cause no charge and hence no interactions with any charged residues of the skin) chemically bind to amino acids (weird enough, ‘normal’ sugars usually don’t do this). Said reaction is also called Maillard reaction and gives fried/baked/roasted foods their typical flavours and, in a pathological sense, leads after long enough reaction times (months, years, decades) and several rearrangement steps to Amadori products and fianlly advanced glycation end products (AGEs). AGEs are for example responsible for long-term issues with poorly treated diabetes but also occur during normal ageing and are contributing to becoming visibly/health-wise old and not just old on the calendar.

Why Pentavitin should react instantaneously (totally against laws of chemistry… and even if, then every reducing sugar would do the same) only with keratin (how should their isomerised sugar know the difference between a lysine residue of keratin and that of any other protein? Magic?) and why this reaction should be good (it certainly isn’t) remains a mystery to any sane and educated person.

The graph @zetein posted shows isomerisation of glucose to fructose… as he said, high-fructose corn syrup. The chemistry/theory of the reaction is sound and, with the aid of enzymes and pyridoxal phosphate, is part of our everyday metabolism. However, without enzymes, you have to fry, roast, or bake sugars such as fructose (correct, fructose works better than glucose and free monoglucosides work better than polymers such as starch) with protein rich food, to make the reaction work (it needs to be hot and dry enough to get water to evaporate). How wants to treat his/her skin’s keratin at >200°C for an hour or two and who thinks that this results in a more hydrated skin?

Show the consumers some chemical structures to make them think ‘Wow, that company is so scientific, they really have to know their shit!’…

[Pharma]

A good part or petroleum jelly is actually mineral oil .

Upps, gotta run…

[Pharma]

HAL49 said:

…
Just adding that mineral oil is not quite safe for lip usage

Why do you think so? I hope @Stella is using cosmetic/pharma grade and not poorly refined crude petroleum .

[Pharma]

7% Ritamulse for that small amount of oil phase? No wonder you get slight soaping… However, cutting down on it would further reduce viscosity. Maybe replace some of it with crystal gel network promoters which do not contain lactylates?

[Pharma]

Anna_Maria said:

Sodium chloride doesnt work with any of these surfactants right? 

Salt should work with sodium methyl cocoyl taurate, sodium cocoyl isethionate, and, most notably, sodium lauroyl methyl isethionate.

[Pharma]

Salut Stella,

My guess is that the product said company used wasn’t acutally a cosmetic one but Photoshop… both pictures look like the colour hues have been heavily altered.

I’m all with @Gordof regarding potential irritation.

Your product is anhydrous… this is good regarding stability of ascorbic and kojic acid but might result in a very uncomfortable, sandy feel and punctual irritation where the crystals dissolve on skin. I imagine the balm to be more like a mask which should be removed after maybe 20 minutes or so.

Will it work? If your genetic background is adapted to high solar irradiation, then it’s going to be difficult to do anything effective without causing harm. Maybe think about all the white tourists after a day at the beach. I’d rather have some natural darker tan than look like a cooked lobster (honestly, this is a biased view of mine; I live in Switzerland and the current beauty standard of our youths is different: hourglass curves… impossible to achieve with European genetics). Be happy the way you are because everyone (well, most…) is beautiful the way he/she/it is (or could be, at least on the inside)! Sorry for being a bit sarcastic.

Meilleurs salutations et un très belle soirée à toi!