ketchito
Forum Replies Created
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When did you add both HEC and your carbomer, and for how long did you mix them? They usually go at the very start and require quite some time and mixing to fully hydrate. Also, is that a cleanser? Why do you use SLS (there are better emulsifiers and sodium free, which carbomers usually don’t tolerate).
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Welcome to the club, hehe. The issue is of course their calculators (I once tried several combinations of UV filters, and there was a different in SPF from both tools that went up to 30 points, which is weird since they both should use the same entry info (extinction coefficients, etc.).
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Do you also add sodium chloride? You could try one sample without PQ-7 and adding Guar HPTC at the start (before the surfactants).
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@Gulfam What you should keep in mind first is that even if you add Na4EDTA to a neutral pH solution and then reduce the pH up to around 4, you’ll have the same molecule as if you used Na2EDTA instead (ionization state is dependent on the solution’s pH).
Now, what Belinda might have meant is that Na4EDTA has more binding capacity (more ionized carboxylic groups which are its binding sites) and/or that Na4EDTA forms more soluble complexes than Na2EDTA.
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IFRA always puzzled me, since their evaluations seem to be more loose. Let me put an example: cinnamic aldehyde according to IFRA for the category 9 (shampoos and soaps), can be present up to 0.49% in the finished product (quite high frankly for a known allergen). On the other hand, for Cosing (or the EU), the same allergen should be declared at concentrations above 0.01% for the same category of products. While the EU doesn’t ban the allergen, that you have to label it above 0.01% make fragrance companies to at least use that ingredient with some caution (theoreticaly, under IFRA you could have a shampoo fragrance purely made with the allergen and comply with their regulation). That also reminded me why IFRA opposed to the release of the 82 allergen new list from the EU, back in the day.
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That type of opacifiers don’t like salt that much, so try to reduce it. Also, if there’s a cationic material in your formula, that could also impair its stability.
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Fragrance level and natural oils are a red flag, especially if it’s an after shave. People for sensitive skin can show reacciona to fragrance allergens and free fatty acids (especially high levels of oleic acid). Having an antioxidant is needed, but as @abdullah suggested, that level is way too much. Also, if that Aloe Vera extract is a water or PPG based one, concentration is usually low; more over, if you solubilize it, much of it won’t be available to interact with your skin. You could use some bisabolool instead.
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I only used a couple of tools for formulation: Mini tab, and GPTs.
With the former, I heard from different disciplines that younger professionals rely more and more on this tool and neglect formal training and knowledge, which I find more like a disadvantage since that tool needs to be feed, and its results interpretation will lack the perspective that knowledge and practical experience provides.
With GPTs, I find that you need to e really precise, to the point that you really need to know your stuff for it to be useful (else, it’ll lie right to your face). Also, when reviewing evidence, GPTs might often miss critical papers/reports.
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I’m aware Mini tab is not an AI tool….it’s just my monthly rage against it 🤓
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Glycerin can be sticky when you use more than some level, like 4-5%. But I understand now. Yes, you could use a mixture of humectants (unfortunately, not the occlusive ones since they are not water soluble). For a water based serum, perhaps Glycerin, PPG (or Urea) and Hyaluronic acid could work well.
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Tetrasodium glutamate diacetate has 4 possible groups available for chelation (they are carboxylic groups). The idea is that you go as high on pH to have them deprotonated. The best performance is actually at a pH over 9, but that’s not a normal pH of a cosmetic (same cas if you want to at least have 3 deprotonated groups, which require a pH above 6). Now, at a pH of above 4.5-5.0, you at least have two deprotonated groups, which is ok (not great, but ok). Citric acid can work as a weak chelant, and it happens that at a pH above 5.0, it also has 2 groups deprotonated. That’s why it can help bosst Tetrasodium glutamate diacetate. Unfortunately, lactic acid is not as useful since it only has one carboxylic group.
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I advise not to buy into supplier’s fairy tales. If that 30h test was done independently and compared to glycerin, then glycerin might have kicked acetamidoethoxyethanol’s ass. Considering both as hygroscopic materials, glycerin has the ability to bind more water molecules and more tightly. It has other properties as well when entering skin, and the best part, it’s super cheap.
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So, the material has 2 CAS numbers associated. One has a petroleum origin while the other has a vegetable origin. Now, since neither start with an exact chain lenght distribution (which happens with pure synthetics), what you have is a mixture (that’s why it’s C13-15…they can actually have also C12, C11, C16, etc., but C13-15 are most abundant). What I mean with all this yada-yada is that one supplier can have a material with more C12 or C13 while other have more C15 or C16. That’s the trade-off for not using completely synthetics 😄
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Hi! No worries….and I think you’ve got a nice answer on that other post 🤓. For what you described, there shouldn’t be any issue.
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Not sure I can remember everything, hehe, but I’ll do my best. GMS, cetearyl alcohol and stearic acid (non neutralized) fall in the same conversación. Rather than being low HLB emulsifiers, they are structuring agents. Let’s put it this way, if Beyoncé is the high (very high) HLB emulsifier, Jay Z (for better or worse) would be her low HLB emulsifier, meaning that in an emulsion, they would have more or less equivalent positions. What happens with GMS, stearic acid and cetearyl alcohol is that, when forming a lamellar structure with the high hlb emulsifier, they will occupy the corners of an hexagonal arrangement, leaving the central stage to the high hlb emulsifier.
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Have you tested a similar product with that amount of niacinamide? I used a cream for sun spots that have niacinamide at around 3-4%, and it was stinging at the start (in the instructions, they even mention that the cream can cause some temporary redness of swelling, which is common in niacinamide containing products). Now, 10% is quite a lot, and if the pH is low and it hydrolyzed to niacin, it could be even more stinging.
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That could mean that the H2O2 was not evenly distributed, which is then corrected after mixing.
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As @graillotion said, the amount of energy (time and speed) is formula and reactor-size dependent. Formally, when you go from lab to plant, you’d need to calculate different parameters like BTO, power number, heat gradient, etc.
As a general rule, for a regular O/W emulsion with waxy emulsifiers and structuring agents, and a decent amount of oil phase, for a 50gal batch and one high-shear homogenizer, I’d emulsify close to 80C and with high shear for close to 10 min (it should be a bit less when increasing the diameter of your homogenizer compared to the diameter of your reactor), then I’d switch to a helical mixer. If the product is lighter (like a lotion with few and soft waxes), I’d cut the emulsion time to 5 min under high shear.
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If I had the budget, I’d use Cetyl HEC. Not only it gives you more stable emulsions (I had some phase separation when using HEC, which was fixed when using Cetyl HEC instead since it interacts more with both phases which HEC doesn’t), it has a more pleasant feel when spreading (not a huge difference, but at least perceivable).
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Oh, I’ve got it. And why can’t you change the manufacturing process (that’d be the easiest thing to change, unless you require some specific equipment)? If all your materials are liquids (I see no need to heat then), you can add some polymeric emulsifier to make your emulsion more stable (like Sepigel 305).
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@abdullah Did you have the same turbidity with 4% of STPP than with 0.5% of STPP?
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I’ve worked with peroxide-based formulas in the past. To mitigate conditions that can impair their stability, you need to first keep a low pH (a pH below 4 is recommended) and use chelants (diphosphonates -like HEDP- are the best for the job, but not so popular in cosmetics).
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You could use both citric and lactic acid (many formulas for hair do, just check on the new Elseve formulas, especially the ones for shine and damaged hair…there’s a very nice strenghtening effect from the use of organic acids based on scientiffic evidence).
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Those ingredients have more chances to resist if they are in solid/powder form, in a tightly sealed package (inert gas should be a lot to ask, but at least some vacuum would be nice) and not exposed to direct sunlight 🤓
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I wanted to chip in on @Aniela‘s nice metaphor with a funny comment, but I woke up with zero creativity today 😅. I’d first start with including both Dimethicone and Black Seed Oil to the oil phase and removing (or bringing up to 0.01%) your Irish Moss Extract. It’s best to have all the oily-heat resistant-ingredients in the oil phase since oils within micelles oxidize less that free oils. Now, it matters which type of mixer you’re using: a high shear homogenizer works best to create more homogeneous emulsions, while low shear would probably leave part of your oils as free oils in your system (and more prone to oxidation). Now, I like the knight metaphor, only Tocopherols are more like Lord Farquaad (cheap reference to my favorite Shrek movie), while something like Tinogard TL is kinda Christian Bale in The Dark Knight (sorry no sorry Ben Affleck). I believe nature was a bit lazy when synthesizing Tocopherols and didn’t want to handle some nice amines and a couple of more cyclization reactions…but she (yes, she) made Henry Cavil and Amy Adams, so it’s fine.