ketchito
Forum Replies Created
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I’m sure @Perry44 will have a better explanation, but I wanted to chip in if I may ????. I believe Perry was more prone to use other type of polymers than proteins for hair. Actually, what you put in your formulas are not whole proteins (since they are mostly insoluble), but hydrolyzed forms. From there, you’ll have peptides of different sizes. The big ones can still form films, but the smaller ones won’t. Filme from peptides are brittle and inferior than for instance silicones. And small peptides are either too soluble to reach hair or just getting inside hair by chance without altering its mechanical properties. For hydration, the best hydrator of all times is water, hehe…what you need is something to lock in hydration, and that’s when film formers like silicones or mineral oil are good at.
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This article from Science Magazine is very comprehensive: https://www.science.org/content/blog-post/sodium-benzoate-nonsense. Decarboxylation of benzoate is not easy to carry out, especially in normal conditions (catalysts and other conditions are often required).
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Glycerin doesn’t improve viscosity and in high leves, it could actually impair it. Plus, it kills foam. Decyl glucoside is a good surfactant, but can also impair viscosity. Try first without it, and if viscosity is OK, add it in increasing doses in newer prototipes.
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Try removing glycerin, coconut oil, olive oil and decyl glucoside. You’ll notice then the viscosity response from salt addition. Also, increase your SLS a bit, or change/add some SLES.
I’d advise to switch to a more robust preservative system.
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Gillete Shaving Gel has neutralized fatty acids as surfactants. In fact, part of those fatty acids remain no neutralized, to give a more stable and creamy latter.
Your system is quite different, but if you choose to mantain it, I’d decrease the carbopol since it might be delaying your flash soam. Rather, I’d increase your CAPB to get a gel-like phase due to the SLS-CAPB micellar entanglements. Also, remove or drastically reduce your glycerin since it can impair your foam.
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@bluebird At low pH, you have a high concentration of H protons, which will stick to electron-rich centres like oxygen in benzoate. That’s why at low pH (blow its pKa), you have benzoic acid.
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Just as a comment, the reaction of ascorbic acid with sodium benzoate requires very specific conditions, not usually met in cosmetics.
Now, I wouldn’t worry much about mixing Sodium benzoate with cationic surfactants at low pH, since you’ll have benzoic acid instead (the extra hydrogen will “hide” oxygen negative charge you have in benzoate, preventing it to react with cationics). The story would be different at higher pH, but cationic systems in cosmetics are usually use in rather acidic bases.
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There are some excepcions to the rule of not mixing cationic surfctants with anionic surfactants. There are few papers on the matter. But in the case you mention (solid bars), they do it so you can get a hard smooth bar. Now, I don’t see much issue there since when you lather, SCI for example, will rapidly dissolve in water, while Behentrimonium methosulfate will not, so they won’t actually meet, or at least not to cause a dramatic loss in foam or performance. The cause would be different if you add Cetrimonium chloride to a shampoo that has quite some SLES, forming precipitates when they meet.
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For an anhydrous product like yours, you don’t need an emulsifier. In fact, it might be the emulsifier the responsible for the crystallization since it’s mainly waxy.
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To your question, you’ll have a New pH is you mix solutions. While your soap once diluted in water will have a pH, the acid mantle on your skin will be in a somehow solid crystalline state. So at the end, rather than mixing, the surfactants from your soap will strip off the acid mantle on your skin.
Now, that you didn’t experience any issue with the use of soap doesn’t mean some other people won’t either. That’s one of the reasons clinical trials are done with a lot of people.
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My proposal is to either have a not so low pH so that CAPB can properly interact with your anionic surfactant, or to add a rheology modifier that works at low pH.
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Upon dilution, the final pH will eventually be same as water. Even at low dilution (like 1:1 water/shampoo) you’ll already have a pH above 5, and that increases very rapidly. Before adding any water, there’s little difusion of your actives to hair surface due to high viscosity of shampoos. What you need is to have a system that produces high coacervation, and enough detergency to remove most of it later.
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Here’s one reference: https://pubmed.ncbi.nlm.nih.gov/18505536/. You can actually find more online.
pubmed.ncbi.nlm.nih.gov
Pemulens(R) (BF Goodrich) are hydrophobically-modified copolymers of acrylic acid (Acrylates/C10-C30 alkyl acrylates) that could act both as primary emulsifiers for o/w emulsions and viscosity enhancing agents. The aim of this study was to assess the influence of different processing conditions … Continue reading
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I agree with @camel. Also, to help speed up hydration, you could add some base (like sodium hydroxide) after mixing HEC for a while.
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Do you need to go that low in pH? Most shampoos have a pH between 5.5-6.0. CAPB has a better interaction with anionic surfactants at higher pH, so maybe that’s what’s causing your pH drop.
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You can disperse the guar HPTC in water and then add citric acid to speed up hydration. Glycerin doesn’t hydrate guar HPTC but helps disperse it.
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There are for sure different ways to achieve that rather than using this emulsifier, like using ceramides, glycerin, some fatty alcohol (that can be converted into long chain fatty acids), etc.
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If N9 is nonylphenol ethoxylate, then that material is banned. I don’t know of any country that still allows it, but there might be, but it can be easily replaced by different aliphatic ethoxylated fatty alcohols.
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I’d remove glycerin since it’ll kill the little forma you’ll have. Also, you have more than enough hydration from water, what you need to do is restore hair’s hydrophobicity. Also, your balance of methosulfate and fatty alcohol is a bit off. I’d use something like BTMS:FFAA 1:3 (as total active matter). That’ll make a more robust emulsion. I always had bad times using a cationic polymer in these type of emulsions, so check for phase separation in the oven. And also, manufacturing method is key (it’s not the same adding CAPB in the cool down process than at the start.
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Manufacture conditions like the ones mentioned before, directly impact molecules difusion, collisions, orientation, packing, tansfer, water uptake, etc. And it all gives the final aspect of your emulsion. As a very general rule, high temperature, high mixing speed and time, and medium-slow cooling give you a very stable emulsion.
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Got it. I recommend you to do a patent search. I’ve seen few where they describe both the composition and methodology. You can also find that info in few formulation books. In fact, more than the composition, it’s the methodology (especially the cooling process) what’s important for proper crystallization.
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My apologies. I missed the part where it said it’s a car shampoo. There are a few very nice formulating books for that: Advanced cleaning products formulations, and Handbook of detergents part D: formulation.
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Hi! I’m my country, government requires you to show stability studies to sell your products, and that’s done with at least a dedicated oven set at 37-40°C. That actually helps you check if there’s something wrong with your formula or not. You can also run some calculations to check if the amount and type of structuring agent is in good proportion with your emulsifier, to have a stable system, but at this point, the heat stability is needed for you. You can find second hand ovens for that purpose online.
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Since your formula has many conceptual issues, it’d be better to get some more academic knowledge before continuing, so you understand what you need to put, what has no reason to be included (rather than a MKT story wich suppliers are very good at), and how to properly mix them. Without the proper knowledge, it’d be hard to know which information is reliable and which one is Just BS. There are a couple of good books to start with: Harry Cosmeticology, and Poucher’s Parfums and (I forgot the full name, but you’ll easily find it).
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Could you be a bit more specific? There are many cold-process pearlizers that fit with your requirements. Also, different polymers to stabilize them, so it’d be helpful if you give a bit more detail about your issue.