[Pharma]

H2O2 is a strong oxidising agent. Depending on concentration and contact time, it can turn many but not all colours into carbon dioxide and other small colourless molecules. 3% is not much and fatty acids aren’t it’s favourite ‘prey’; therein, it tends to speed up ‘rancidity’ which causes not just degradation but also polymerisation of peroxides which result in yellowing.

You shouldn’t mix H2O2 with oxidation-prone products!

[Pharma]

You could use other benzophenones instead.

Benzophenone-3 shouldn’t be a problem because it’s use in hand washes and photosensitisation won’t be an issue. It’s unfortunately commonly regarded as ‘bad’.

Benzophenone-5 is the sodium salt of BP-4.

Use a different sunscreen UVA filter such as diethylamino hydroxybenzoyl hexyl benzoate, butyl methoxydibenzoylmethane, or bemotrizinol.

Try ferulic acid: It doesn’t absorb as good in the UVA range and is less stable than common UV filters but it’s natural.

Use a different bottle material which is less transparent for UVA (polycarbonate, polystylrol, or plastics with additives).

Try without any BP-4 and see if you still get photobleaching.

Use chemical protection such metabisulfite.

[Pharma]

Lecithin might be in there to help ‘bind’ oils and butter together?

Glycerol is likely for skin conditioning and because people love it.

[Pharma]

These are for hard surface disinfection and require registration i.e. efficacy testing by authorities. Nothing a layman should attempt making, let alone selling. That’s why.

[Pharma]

It’s the same with masks. Everyone who knows how to stitch two layers of tissue together creates re-usable masks for horrendous prices. If only stupidity would hurt not just the people around but the idiots themselves…

[Pharma]

amorical said:

…not to mention the emulsion broke when I diluted it so the wax was floating on the top… 

For pH readings you don’t have to bother with emulsion stability and if the wax floats on top, just remove some if it’s in your way.

[Pharma]

@amorical There’s no point in filling anything out in the form @Perry posted because the only thing they have to offer for your high pH product is DMDM Hydantoin & Iodopropynyl Butylcarbamate

pH 10 is indeed a problem for several synthetic and natural preservatives containing for example an ester function such as parabens or GMCY. Getting the pH down to 9 would allow for pretty much any you like (except acids which require a way lower pH). On the other hand, 10 is also a pH at which you won’t have to care about yeast and where only a few bacteria can grow; several different fungi won’t mind, though, and they might grow mainly on the surface, you hence need head space protection -> these compounds are per definition VOCs (though might not pose any restrictions due to low usage %). If you manage to lower water activity, you’ll be +/- left with just fungi to worry about. In other words, you won’t need additives which target bacteria.

How much water and glycerol do you use?

[Pharma]

Ups, I forgot to mention sugar to reduce water activity!

Honey but also fruits are rich in these.

Read slide 33 & 34 of THIS presentation for the answer regarding pH or in other words the amount of required citric acid. The lower, the better but sadly, not necessarily the better tasting…

[Pharma]

The lower pH due to citric acid is just one step of gummy bear preservation .

The second one is very low water activity (glycerol and gelatine). However, this may not apply to certain vegan recipes which require additional strategies.

[Pharma]

You have to be transparent and have to declare what you use!

Thiazolidinones are strong preservatives and widely used (most pain and many cleaning products for laundry/cars/dishes contain it -> often undeclared because of different regulatory guidelines). I really don’t like them (bad for the environment and rather poor investigations regarding overall safety etc.).

Don’t use a ferment or a herbal extract based preservative. These are likely to break down and fail at elevated pH.

[Pharma]

HERE is a link to a list of commonly used denaturants by the biggest ethanol producer in Switzerland.

Due to aforementioned severe health concerns, many countries no longer use methanol as denaturant, not even in spirits for burning purposes (nonetheless, these are colloquially still called ‘methylated spirit’ even if there is no methanol present). Should you have ‘real’ methylated spirit, don’t use it as hand sanitiser!

Deciding between probably dying from COVID-19 or probably dying from methanol intoxication is a very tough. Although, it might not make that much of a difference whether you get a fever, start coughing, and then die from respiratory failure or become blind, get metabolic acidosis, and then die from respiratory failure… sorry for the morbid humour.

[Pharma]

Here’s some of the more common semi-synthetic amino acid based chelates (don’t know if all are cosmetics approved): EDDS, EDG, GLDA, HIDS, IDS, and MGDA

GLDA (Dissolvine GL) is cosmetics approved, the L-enantiomer is readily degradable, and also very efficient. Depending on the product and pH, it is somewhere between citric acid and EDTA and best used in combination with a small amount of citric acid.

EDDS is the only one which can even by produced by fermentation alone. It is very well suited for slightly acidic products and outshines EDTA there. It is an approved cosmetic ingredient commonly sold as trisodium ethylenediamine disuccinate.

[Pharma]

It’s by far not as effective as EDTA especially at pH towards the more acidic side.

Really natural is phytic acid and there’s a bunch of strong chelates which are derived from amino acids and, though synthesised to some extent, are fully and readily biodegradable.

I don’t like EDTA mostly because of poor degradation in nature and its excessive use throughout industries including agriculture.

[Pharma]

There are always trace metals present, even in oils. Especially when working with natural ingredients, adding a chelate is highly recommendable. As @ngarayeva001 said, chelates boost most preservatives and increase chemical stability as well.

I nearly always use chelates/sequestrants.

[Pharma]

It has a timer and a temp function as well as ‘regulated’ humidity (though that one’s just some water underneath in a reservoir).

[Pharma]

Phenethyl alcohol is slightly volatile and preserves head space (that’s the air up in the bottle/jar). It behaves like a perfume, so to speak.

How much water and how much glycerine does it contain? There’s the chance that you could use propylene glycol instead.

Else, there’s a bunch of other more or less natural/green/alternative preservative mixtures out there but yes, many of the pH independent ones contain phenethyl alcohol or else phenylpropanol (a similar compound). They make the blend way safer in terms of microbes, allow for a lower % of the other preservatives in the blend (lowers cost and ‘stickiness’ of glycols and has also lesser impact on things like viscosity), and are okay if the product isn’t eaten spoonwise.

Phytate is not a preservative but a chelate which boosts antimicrobial activity of many preservatives and helps against olive oil going rancid. It’s a good and safe choice. Phytic acid is the main storage form of phosphate in cereal grains, nuts, beans, and many more seeds -> you eat phytates every day. Usually not the healthiest food constituent for humans but you could actually eat it spoonwise :smiley: .

[Pharma]

The first is a fragrance .

The second, I couldn’t find anything.

The 3. & 4. are isooctanoic acid isomers. In cosmetics, using the name iso-blabla for mixtures of different blabla isomers containing mostly iso-isomers but not only that is okay. An example are isostearates. Still, I don’t think that in this case you should call them that but go with the ‘real’ name unless they are not approved cosmetic ingredients (and you shouldn’t add them) or can be termed ‘fragrance’ as well.

INCI is not a strict science but rather imprecise and often employs traditional names or colloquial terms and sometimes it’s not even fully defined. It’s not like IUPAC, SMILES or other chemical nomenclatures with which everyone is able to name a compound just by looking at it’s molecular structure or vice versa draw it from the name.

[Pharma]

What about alcohol (upss, a VOC ;( ), glycols and glycerine? That’s the only food grade ‘preservatives’ I can imagine work at higher pH and don’t sound too scary (okay, alcohol makes you drunk and simpletons believe that all glycols are antifreez). Or omit water in your product.

Silver can work but not at higher pH and not in most formulations. Pyrithione is not safe to eat like most of the others I can think of.

Apart from that: most preservatives requires low pH, sound like super scary baddies, are non-edible, have been banned years ago, and/or are utterly useless… may we see the whole composition?

[Pharma]

If it’s for ‘heat treatment’, I’ve got myself an egg incubator .

[Pharma]

3% is too harsh for repeated use.

[Pharma]

I have the impression your mixing up fatty alcohols (e.g. cetyl alcohol) with fatty acid esters (e.g. cetyl palmitate), but anyway…

Myristyl myristate is softer and shinier, less of that dry silkiness cetyl palmitate has, but else is quite similar. I don’t like it that much because of the shine, I like the silicone velvet shimmer more.

I wouldn’t know of any fatty alcohol for your job (they are all very similar), but regarding esters: If you have a hard wax (carnauba or beeswax), about half as much 5-wise is fairly similar to cetyl palmitate in the jar and during application, just a tiny bit more sticky, draggy, and less spreading. The final feeling is more waxy (obvious), again stickier but with better occlusion and not too much shine. On the other hand, the softer candelilla wax comes close to myristyl myristate with the (dis-)advantage of being a wax.

One fatty alcohol which is different would octyldodecanol. It reduces viscosity in some preparations (i.e. true o/w emulsions, personal observation) whilst increasing it and hence stabilising laminar networks (i.e. most easy formulations). It’s oilier but not the kind of sticky oiliness like castor oil, more like a fast absorber. No occlusive effect but better emollience.

For your demands, I’d swap some of the liquid oils with a partially hydrogenated oil. Gotta run, dinner’s ready

[Pharma]

Sewing and gluing newspaper, spraying and drying etc. sounds like a lot of work… why not bin bags? They are easy to use and air- and hence virus-tight.

[Pharma]

Fekher said:

Hi professionals,  I found in many sites that hydrogen peroxide can be effective for Coronavirus with just 1 minute needed contact time.
  Have anyone idea about it?
@Pharma @Perry @Agate @Cafe33 @ozgirl @lmosca @Gunther 

Depending on concentration, even 1 second might be enough but your going to have a loooot of pain too :smiley: . H2O2 for surfaces = great, for skin not so much because it kills skin cells (nearly) as good as it kills microbes.

[Pharma]

helenhelen said:

…Is the “dry-ish silkiness” a similar effect to using isopropyl myristate?

And how different is the effect of cetyl palmitate to cetyl alcohol?

No, IPM feels different and ‘dry’ because it spreads easily and penetrates fast whereas cetyl palmitate remains on the skin as something which feels (to me) a bit like powder and turns oils less slippery/greasy.

Cetyl alcohol and cetyl palmitate are complementary, they cover two different aspects.

Cetyl alcohol doesn’t ‘feel’ on the skin… well, sure it does but the effect is not very noticeable in a cream IMHO. Cetyl alcohol changes the cream itself which is mostly an effect on viscosity, stability, and optics. Obviously, viscosity is felt upon application but just when scooping the product out of the jar and then for the first seconds of application but then quickly fades away during rubbing in. That’s when cetyl palmitate starts showing and excels once the cream has absorbed into the skin, it’s the finishing touch that remains. My wife has very fine/sensitive skin and she can feel cetyl palmitate and similar (e.g. waxes) during application. She can’t quite put it into words but she complains about the ‘dryness’… for her, it probably feels like fine waxy grit, maybe like adding too much beeswax? And then she complains that there is not enough coverage/film remaining on the skin (although you can see that there is, it just doesn’t feel like being there). Perception but also expectation are very subjective and individual .

[Pharma]

Graillotion said:

… I noticed that behenyl alcohol involves some long chain fatties…. The formula already includes 1% Jojoba and 1% Meadowfoam… Is there a chance I would be getting too much long chains, and hence causeing a problem of some kind…..albeit formulation or skin feel?

Behenyl alcohol is one fatty alcohol with one long chain (nitpicking here).

Jojoba oil is a wax (= ester of a long chain fatty alcohol with a long chain fatty acid) whilst meadowfoam oil is a triglyceride of long chain fatty acids. These are pretty different and there is no obvious reason why adding 1% fatty alcohol would change/hamper anything. Sometimes mixing different chain lengths increases emulsion stability (e.g. cetearyl alcohol is ‘better’ than cetyl alcohol).

I don’t know if there is a ‘feel difference’ but behenyl alcohol has a higher melting point and might be more suitable if you’re not the person who likes low viscosity products (though there is nothing a bit gelling agent might not correct ).