[ketchito]

@Abdullah HDPE is used in bottles indeed. They are formed by straight chains of ilyethylene molecules of different chain lenght (molecular weight). By changing the average molecular weight, you can get vary the rigidity of the bottles. Also, since polymer molecules are straight, they pack better and prevent light from going through more efficiently, giving a more solid opaque white color (which can be mixed with pigments, like in the first three images you showed). 

Low density polyethylene consist of straight and branched polyethylene molecules, which prevents them to pack tightly, being more flexible than HDPE and letting a bit more light to go through. That’s why plastic bags are “slightly” transarent.

PET is a different type of polymer, and is completely clear (can be coloured though). It’s also very shinny on the surface.

[ketchito]

@Abdullah Just check closely the purity of your CAPB. CAPB has been found to be allergenic in some studies, mostly because of some organic impurities.

[ketchito]

@ESChemlover In general, the preservative system in your formulas might not be robust enough, especially with the type of extracts you’re using. Also:

1) not sure how much glycerin you’re using, but you use it in a cleanser only as claim ingredient, also, so your foam is not impaired  

2) amidoamines are not usual in skin leave-on products; maybe you could switch to a non charged emulsifier?

3) why are you writing Vitamin A in your Pistacia? If you meant it as a source of it, you better mention that, since the INCi of vitamin A is different. Also, don’t use much of Aloe Barbadensis, sin it can increase the risk of microbial contamination of your product.

[ketchito]

@coco Since your oil phase is low in size, you might be trying to form an O/W emulsion, but you don’t have a proper emulsifier for that. You could add an ethoxylated non ionic surfactant or add a polymeric emulsifier.

Also, adding oils in the cool down phase of your emulsion could also be destabilizing it (better add them as part of your oil phase, if they resist heat).

[ketchito]

Abdullah said:

@ketchito in the ulprospector Link, what is your opinion about these two

Other factors that effect deposition

1. Coacervate rheology
is it the actual product viscosity or product viscosity during shampooing when coacervate is formed? 

2. Electrolytes reduce the amount of coacervate.
doesnt it mean reduced deposition? 

1) that’s a good question; I believe it’s products viscosity, since, if the product is too viscous, it’d be hard to dilute it so coacervate is formed before you rinsed-off the product

2) both, ’cause if you reduce the amount of coacervate formed (electrolytes interfere with anionic surfactant-cationic polymer electrostatic interaction), then there’s less coacervate being deposited

[ketchito]

@mizzm 5% of dimethicone is definitely too high for a conditioner. You can try a formula with around 2%. Also, even 1% of Panthenol in these type of formulas can be a wastw, since it’s basically a claim ingredient in a rinse-off.

[ketchito]

Abdullah said:

@ketchito “pseudomonad siderophores have a greater affinity for Fe, Mg than hydoxamates - cap, ZPT, NaPT.” 
Does this sentence mean pseudomonad can consume Fe & Mg even after they are chelated by caprylhydroxamic acid or it means something else? 

@Abdullah You might want to read this:

Wherein, caprylhydroxamic acid (CHA) adopts this content energy potent mould fungus inhibition—growth of Aspergillus niger (A.Niger), and antibacterial principle: CHA is to Fe 2+And Fe 3+The efficient selective chelation is arranged, in the iron ion constrained environment, the growth restriction of mycete; Ferrum is the key element of growth of microorganism, and Microbiological release chelating agen (siderophores) is caught Fe from environment 3+And it is converted into Fe 2+CHA chelating Fe 3+Stability constant high, can prevent that mycete (A.Niger) from obtaining ferrum element; And it is still effective when pH value is neutral, is antibacterial desirable organic acid. (ref.: https://patents.google.com/patent/CN102920612A/en)

Caprylhydroxamic acid would compete with sidophores molecules to bind available Fe ions (same as brides compete for the last cheap nice dress during black friday). As @Pharma mentioned, sidophore binding with Fe ions is better when they are in the Fe3+ state. 

[ketchito]

@Abdullah You can actually start with this book: Principles of Polymer Science and Technology in Cosmetics and Personal Care.

ULprospector also has an article about it (although only related to coacervates): https://knowledge.ulprospector.com/638/pcc-understanding-deposition-rinse-products/

Now, here are some interestin papers (the first ons is my favorite on the topic):

1) http://www.scientificspectator.com/documents/surfactant%20spectator/surfactant%20interaction/2006%20Coacervate.pdf
2) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9292326/
3) https://www.jstage.jst.go.jp/article/jos/68/6/68_ess19081/_pdf
 

[ketchito]

@PhilGeis I totally agree with you. I remember some debates around the contribution of phosphates from cosmetics, compared to industries like farming. One of my clients was forced to replace STPP from his detergents long time ago. HEDP was on the radar also, but because of its poor biodegradability. 

Unfortunately, both USA and Europe have now stricter regulations towards phosphates (and I say unfortunately, because the push always comes first towards the cosmetic industry, rather than to the industries with the highest impact on the matter). 

[ketchito]

zetein said:

@ketchito That would be strange because other phosphates aren’t restricted in cosmetics, like polyphosphate, triphosphate metaphosphates which worked as builders in detergents and caused seaweed disaster in the past. Also things like distarch phosphate and alkyl phosphate are freely and widely used.

You can check this: https://pubmed.ncbi.nlm.nih.gov/29751423/

You can check also the many studies and regulations meant to reduce phosphorous in finished products, like this one from EPA: https://www.epa.gov/nutrient-policy-data/epas-efforts-redu.

[ketchito]

@zetein Perhaps it has to do with the eutrophication issue related to phosphonates. They are actually being replaced in household products. Nothing else comes to my mind.

[ketchito]

@jeremien I don’t think the issue with peptides is that they are not able to interact with certain receptors (they are bioactive, for sure), but that their use in topical cosmetic products is justified. Both papers you mentioned bypass the SC: in one, peptides are applied to an open wound, and in the other, they are injected. That’s different than topical application to preserved skin. And there are limits to encapsulation, especially how far it can penetrate.

Lately, you want to see these peptides evaluated in well controlled clinical trials, and as @Perry mentioned, there hasn’t been convincing evidence in those (only the ones from suppliers).  

I always recall an ingredient called Procapil (from Sederma), which has been in the market for years, promising a natural way of treating hair loss…and yet, the only actives approved (so far) are Minoxidil and Finasteride, since they are the only ones that showed real benefits in multiple and well controlled clinical trials.

[ketchito]

@Abdullah I recommendo you to search and download papers on the matter. There are plenty, from the Journal of Cosmetic Science, Langmuir, el Journal of detergents and surfactants, Polymers, etc. Try searching through Google Scholar.

[ketchito]

@grapefruit22 Big companies (like P&G, Unilever, L’oreal) are the ones still relying on the high performing preservatives (formaldehyde donors, benzoate/phenoxy/benzyl alcohol combo, and even isothiazolinones mixture). They for sure conduct proper microbiological testing. While small companies are the ones mostly using the newer “more natural” blends. Don’t believe they conduct proper micro studies, but in the recall reports, I see many products with these systems fail.

[ketchito]

You can check thus doc: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.ashland.com/file_source/Ashland/links/PHA18-101_Natrosol_250_HEC_Formulating_elegant_liquid_and_semisolid_%2520drug_products.pdf&ved=2ahUKEwitncmlkLf5AhWxBtQKHZZHBvEQFnoECAgQAQ&usg=AOvVaw3LXgR-GX_CKS6_vZBGFYQI

[ketchito]

I used to do aerial dance (silks), and always came across a group of women that did pole dancing. I even tried (being a man) once to get on the pole, and it’s quite an exercise, so my respects to pole dancers…from the fitness point of view, of course ????

[ketchito]

@shivani The main risk of hard water is for your product, especially if you have highly charged anionic surfactants (like Sodium lauryl sulfate). You could use a bit more that usual of your chelating agent. Sometimes mixtures of chelants work synergistically.

[ketchito]

@Joy I understand Sodium cocoyl isethionate is stable within a narrow pH range, outside of which, it hydrolyzes. Since Optiphen has Sorbic acid, it might be shifting the pH outside your safe range and due to the high temperature, the hydrolysis of SCI might take place fast. Just a theory, though.

[ketchito]

@Abdullah If PQ-10 have deposited as a coacervate, NaCl would help remove it in the next wash, although not as much as if PQ-10 had deposited alone. 

By desorption, yes…I meant from hair, once the polymer had already deposited.

[ketchito]

@fotis83 It really depends. I agree with @Abdullah, to have an anionic as main surfactant (due to cost and type of foam). Detergency can be boosted with a non ionic (like Lauryl glucoside), and foam would be increased with an amphoteric or pseudo-amphoteric (like a Betaine, Amphoacetate or Amine oxide -formaly a non ionic-). You need to carefuly choose since different molecules from the same family could impact viscosity differently.

[ketchito]

@Formi If you have the chance, run some microbiological test on your Hydrolyzed silk. We identified often contamination of some batches of our hydrolyzed proteins, which are very sensitive to contamination, especially the ones poorly preserved.

[ketchito]

Abdullah said:

I don’t know how much correct it is but someone told me that i should have at least 0.1%, ideally 0.15% organic acid in it’s acid form + a preservative like phenoxyethanol for bacteria + EDTA.

That would be at least 0.7% sodium benzoate at pH 5 to get 0.1% in acid form. 
At pH 4.7, 0.5% which is upper limit for leave on product would give you 0.1% in acid form. 

This is not for cleansing products. 

I am looking to hear from experts here about this. 

Please, correct me if I’m wrong @PhilGeis, but some surfactants are able to modify organic acid’s pKa (like Sodium laureth sulfate), which allow formulas to use not as much Sodiun benzoate to have a good amount of free acid at a determined pH. In practice, you don’t see formulas having that much (0.7%) Sodium benzoate for this reason. I believe some cationic surfactants are also able to shift organic acid’s pKa in the same manner.

[ketchito]

@Squinny You can find that info from many references. Here’s an example: https://www.obelis.net/blog/cyclopentasiloxane-d5-and-cyclotetrasiloxane-d4-restricted-in-the-eu/

[ketchito]

@Abdullah It depends. If the cationic polymer adrosbs in its pure state (no coacervate), then salt might reduce its deposition. But if you have a coacervate, salt might actually increase it.

[ketchito]

@Abdullah NaCl as well as orher electrolytes help control the adsorption/desorption of ionic substabces on hair. In the case of Guar HPTC, it helps with the desorption, making it easier for surfactants to remove most of it.