chemicalmatt
Forum Replies Created
-
Sodium sulfate wouldn’t do much Zink. Sodium sulf ITE, on the other hand is keratolytic, yet I don’t think that applies either (decomposes to H2S, sewer gas, poisinous, yadayadayada). You are probably seeking flowers of sulfur, which is sometimes called sulfur florets or colloidal sulfur. Dispersing in oil works best, as it is not water-soluble, not much anyway. This is an old school acne remedy. Old as in 1950’s old.
-
Cosmo, if memory serves, DHA undergoes slow acid-catalyzed hydrolysis to glycolic acid, whereupon you get the extra protons that lower pH. The more water you have in your formula, the likelier this will happen. Perhaps cut it with some propylene glycol. I’m unsure whether a buffer would help, but you may try a glycolic/glycolate buffer system at pH 4.2 and check it out.
There have been many odor blockers over the years, the most common being the lactones. These work in water-based systems. ICI (oops, I mean Croda) might still offer Forestall, which is an alkyl quat that used to work well masking thiogylcolate odors in permanent waves. Other than that, your first guess is probably true: more fragrance, more better.
-
Shah,
I’ll second David’s comment. We don’t mind giving advice here, that’s an altruistic pursuit. But to shell out a working formula is asking for a lot. Shahbaz has already supplied you with a LOT of helpful information; you can take it from there.
Note to Shabaz: SLS vs. Thioglycolic acid in the Skin Irritation Contest, Thio always wins! Nobody will notice the SLS while their skin is being dissolved by the thio along with their hair.
-
Mike, I’ll offer up C12- 15 Alkyl Benzoate (Finsolv TN). As I am fond of saying: what CAN’T it do? Among other things it serves as “Poor Man’s phenyl trimethicone”, since it gives 70% of the shine at one-fourth the cost as your fave, also stabilizes SPF, and is completely miscible with cyclomethicone. It can de-grease petrolatum or beeswax and de-oil mineral oil or any other.
Also in “ester-land” is octyl isononanoate, as versatile a workhorse ester as you’ll find, and one that many suppliers offer now that it’s secret powers have been established.
In the preservation area: p-chloro m-xylenol (PCMX). It has limitations in solubility and odor, but it works great even at 0.10%, at any pH, especially with phenoxyethanol, and is approved virtually everywhere. Originally listed in the British Pharmocopaeia if memory serves, where it was first used to sanitize latrines during WWI. “Poor Man’s triclosan” if you will, with none of the bad press.
(This is a good idea by the way.)
-
Compounder, when you lowered the pH, then added salt, you salted out the saponified coconut/palm higher fractions (C18 +). Leave the pH at 9.0 plus, and don’t add salt. As long as your total solids are less than 25%, you should be OK. If not, just decant the water off and re-tag it as shaving cream. No problemo!
-
Dandy,
With an oil load of 25 - 30%, you could get away with formulating without any GMS or cetyl, which by the way will not work here without a co-emulsifier of higher HLB (that’s why so many supply the glyceryl stearate and PEG-150 searate combo), and just use Pemulen TR-2 polymeric emulsifier along with your Carbopol. No other emulsifer needed - just watch your electrolytes!
-
Avick, if you are talking about oxidative (“permanent”) hair colorants, then film formers and UV absorbers are the best bet. I’m a big fan of deacetylated chitosan as a natural film-former. It’s cationic, grants a soft feel, doesn’t have much of a build-up attitude and might work OK here. (It still won’t work as well as the best of the synthetics: polyethyleneimine.) And no, I do not sell chitosan, so my opinion is neutrally informed. As for natural UV absorbers - uhhh…coconut oil has a SPF 2, I think. Not much help there I suspect.
-
Didn’t DOW invent the Chelation Value spec? Or was it Hampshire? Trivia question only.
Beha, it should be noted Mike is referring to solid state EDTA sodium salts. Some folks like to use the solutions. Calculate accordingly if you are one of them.
-
I seem to recall it also dissolves in other polyols, such as glycerin, sorbitol, ethoxydiglycol, dipropylene glycol. Cannot remember the solubilty factors, sorry to say. Best yet is ethanol or phenoxyethanol - if you can stomach it. I also recall certain amphoterics like coco-betaine worked. Hope this helps.
-
gfeldman, you are correct. You want to enhance, not inhibit, the activity of peroxidase enzymes, Gustavo. As for antioxidants in skin-care formulations, there is a virtual galaxy of them out there. I wouldn’t know where to start there are so many..
-
I’ll just point out here, Jose, that 15% salicylic acid is wart remover country. Just how much “beta-hydroxyacid” do you think you need? You may want to pull back a bit.
-
Jose, that Na stearate gel you speak of only works with lower-chain alcohols and diols, e.g. SDA, propylene glycol. Once you start “pimping out” that system with other ingredients, the gel structure fails and you get an amorphous gunk. You can get a paste-like texture using mixed alkali stearates (K, Na,TEA) , some free stearic acid, and glyceryl stearate, Check out any “old school” shaving cream formulation, then modify from that starting point. You’ll have your pasty scrub in no time. Being soap, it will clean the face pretty well too!
-
Tasia, the only effective cationic ingredient that will solve both issues, and possibly make the cut as “natural” is chitosan (deacetylated). It is derived from critters, not plants though: shrimp shells. It is expensive, especially the HMW stuff, but it works splendidly!
-
Mike,
I think the only rule is how exacting your ingrdient disclosure needs to be to satisfy the legal department in a case such as this. Were this a routine personal care formulation, I would not bother reporting the NaOH, and none would be the wiser, especially since you and I know it does not exist in its purely ionic form but more so as a salt with methylparaben in this case. After considering any possible legal claims against the KY makers (J&J, right?) by KY users could prop up, I’m sure the lawyers said “list it”.
-
You are not being ridiculous, you are the voice of reason! You should draw them that famous graph that exhibits the SPF value as asymptotic from number 45 onwards! A picture might be worth a thousand words here. Also, regardless of chemical sensititvity issues, do you think it is possible for a human test panel to validate that SPF value? Might be nigh impossible, and certainly VERY expensive. Good luck.
-
vjay, if you can cite the source of the article you mention, that would be helpful. I have never heard or read of any mineral interactions with avobenzone; especially with a relatively inert one like TiO2. In any event, you may want to avail one of those singlet-state quenchers (esters) supplied by HallStar since sunlight itself degrades avobenzone somewhat rapidly - that much is definitely known!
-
dmh0023, GMS will not form any pearlescence without emulsifying in water, so an anhydrous pearl isn’t going to happen that way. If you’ve got to have that pearly appearance, and your formula has no water, just add one of the many pretty mica blends (aka “glitter”) and be sure to suspend it well.
-
Gustavo, my only experience with anionic styling resins is with the terpolymer Amphomer series from National Starch (now Akzo-Nobel?) and the ISP Gantrez series.of PMMA/VA copolymers (now Ashland?) These folks give you the equivalent weight and you plug in the correct MW for your alkaline agent, which I recommend be AMP or AMPD, also the degree of neutralization, and this gives you the various properties of film pliability - which you are obviously schooled in already. A helpful hint: use an alkyl amine (e.g. cocamidopropyl dimethylamine) to neutralize and you’ll get a nice firm hold with added humidity resistance, yet a nicer feel. Brazil, eh? Wish I was there - it’s minus 10C here in Chicago. Best of luck to you.
-
Rahma, not to state the obvious, but mineral oil would be best. If you just have to go natural, however, coconut oil (92 mp), meadowfoamseed oil, jojoba oil, and olive oil have been shown to best penetrate the cuticle into the cortex, in decsending order of efficacy. The cortex is where you want to be. Look back into the SCC Journals (since 2004, if I remember) and you’ll find the TRI Princeton study article.